Qualification: 
Ph.D, MS, BS
Email: 
madhavdatta@amrita.edu

Dr. Madhav Datta is the Chairman of ACIRI and a Distinguished Professor in the Department of Chemical Engineering and Materials Science. He has over 40 years of industrial and academic research experience having worked at IBM’s T.J. Watson Research Center, Intel’s Logic Technology Development, Emerson Network Power’s (ENP) Cooligy Precision Cooling, and the Materials Department of Ecole Polytechnique Federale de Lausanne (EPFL). His research interests include: Electronic Materials and Processing, Micro Cooling Devices, Wafer-Level Packaging, Joining Technologies, Electrochemical Processing, and Materials Characterization. Dr. Datta is an innovator with 48 issued US Patents and is recipient of the Electrodeposition Research Award of the Electrochemical Society. Dr. Datta received his doctorate from the Materials Department of Ecole Polytechnique Federale de Lausanne (EPFL), Switzerland.

He was awarded with Ninth Plateau of IBM Invention Achievement Awards and IBM’s Top 5% Patent award. He has authored 90+ publications and is the author/editor of several books on Electrochemical Processing & Micro/Nano electronics. He is recipient of the Electrodeposition Research Award of the Electrochemical Society. International Biographical Center, Cambridge, England included his name in outstanding scientists of the 20th Century in honor of his outstanding contribution in the field of Electrochemical Microfabrication. He has held several administrative positions including divisional chairs in the Electrochemical Society and the International Society of Electrochemistry. He has organized several international symposia and has presented keynote and invited lectures.. 

Dr. Datta received his BS in Chemical Engineering from H.B. Technological Institute, Kanpur, MS from University of California at Los Angeles.

Education

YEAR DEGREE/PROGRAM INSTITUTION
1975 D.Sc. Tech. Materials Department, Swiss Federal Institute of Technology (Ecole Polytechnique Fédérale de Lausanne, EPFL), Lausanne, Switzerland
1970 M. S. in Chemical Engineering School of Engineering and Applied Sciences, University of California, Los Angeles
1968 B. S. in Chemical Engineering H. B. Technological Institute, Kanpur, India

Experience

YEAR AFFILIATION
September 2014 – Present Distinguished Professor, Chemical Engineering & Materials Science, Amrita Vishwa Vidyapeetham
October 2008 – September 2014 Adjunct Professor, Department of Chemical Engineering and Materials Science, Amrita Vishwa Vidyapeetham
November 2003-April 2013 Chief Scientist/Chief Engineer, Cooligy Precision Cooling, Emerson Network Power, 800 Maude Avenue, Mountain View, CA 94034
August 1999 – October 2003 Senior Manager/ Group Leader, Intel Corporation, Logic Technology Development, Hillsboro, OR 97124
November 1984-July 1999 Manager/Research Staff Member, IBM Corporation, T.J. Watson Research Center, Yorktown Heights, NY 10598
October 1984 – September 1985 Assistant Research Manager , R & D Center for Iron and Steel, Steel Authority of India Ltd., Ranchi - 834002, India
September 1975- September 1984   Senior Scientist/Teaching Staff,  Swiss Federal Institute of Technology, Lausanne, Switzerland

Areas of Research Interest

  1. Electronic Materials: Micro/Nano Fabricated Tailored Materials and Structures for Microelectronic packaging; Flip-chip (C4) technology; Lead-free Packaging Materials.
  2. Materials Processing: Electrodeposition, Etching, Electropolishing, Anodization; Advanced Joining Processes for metal-metal, metal-ceramic bonding.
  3. Energy Technologies: Li-metal and Li-ion battery technologies for Electronics; Solar cells.
  4. Thermal Management: Energy Efficient Liquid Cooling Systems for Electronic and Photonic Devices; Micro-Heat Exchanger and Micro-Fluidics devices.

Research

Projects (Ongoing)

Durability of High Performance Nano Adhesive Bonding of Aluminium under Aerospace Environments

Projects (Submitted)

Publications

Publication Type: Journal Article

Year of Publication Publication Type Title

2015

Journal Article

Dr. Madhav Datta and Choi, H. - W., “Microheat exchanger for cooling high power laser diodes”, Applied Thermal Engineering, vol. 90, pp. 266–273, 2015.[Abstract]


A tremendous amount of heat is generated during operation of high power laser diodes that are built as a linear array of laser emitters. The present paper describes fabrication and test results of a microheat exchanger for cooling such high power laser diodes. The cooling module consists of two key components: a ceramic-copper bonded thermal conduction plate with twelve conducting pads to which the laser diodes are mounted and a liquid cooled microheat exchanger containing an internal active microstructure. The thermal conduction plate is joined to the microheat exchanger and the heat generated in the laser bar conduction plate is extracted by flowing a cooling liquid through the microheat exchanger. Design and fabrication of different components of the cooling module and their assembly processes are described in this paper. Thermal test results indicate that the cooling system provides uniform liquid flow and heat transfer rate over a large surface, while maintaining low pressure drop at high flow rates. Long term reliability test data demonstrate the robustness of materials, internal microstructure and fabrication processes employed in the present study.

More »»

2015

Journal Article

Dr. Madhav Datta, “Microfabrication by High Rate Anodic Dissolution: Fundamentals and Applications”, Electrochemical Society Transactions, vol. 66, no. 22, pp. 1-18, 2015.[Abstract]


This paper presents a review of the basic principles of electrochemical metal removal processes and their application in microfabrication. After a brief description of anodic behavior of metals, the influence of mass transport, surface films and current distribution on microfabrication performance are discussed. Some examples of microelectronic component fabrication are presented that demonstrate the challenges and opportunities offered by high rate anodic dissolution processes.

More »»

2015

Journal Article

Dr. Madhav Datta, “Bonded Ceramic-Metal Layers for fabrication of Thermal Conduction Plates”, Journal of Microelectronics and Electronic Packaging, vol. 12, no. 3, pp. 146-152, 2015.[Abstract]


The work described in this article is part of an effort to build reliable and efficient liquid cooling modules for high-power laser diodes. The cooling system is designed to mount at least 12 laser diodes to a common microheat exchanger, thus requiring a large-size thermal conduction plate. Fabrication of the thermal conduction plate involved void-free bonding of copper layers on both sides of an aluminum nitride (AlN) plate. In the current study, ceramic-metal bonding methods using moly-manganese metallization and active metal brazing were investigated. Bonded AlN/copper plates were characterized and evaluated by optical microscopy, scanning electron microscopy, and energy dispersive spectrometry. For detecting voids, cracks, and delamination, some of the plates were analyzed by scanning acoustic microscopy (C-SAM). Results indicated that >99% void-free bonded AlN/Cu plates can be fabricated by using properly selected metallization conditions and brazing temperature profiles. The active metal brazing approach was found to be a cost-effective method of fabricating reliable, void-free thermal conduction plates.

More »»

2009

Journal Article

Dr. Madhav Datta, “Paradigm Shifts in Electronics Enabled by Electrochemical Micro/Nano Processing”, Micro and Nanosystems, vol. 1, pp. 83–104, 2009.[Abstract]


Advances in electronic materials, processing technologies, and integration schemes have resulted in phenomenal miniaturization of electronic components. Since the development of through-mask plating for thin film heads in the1960s and 1970s, an enormous amount of industrial and academic R&D effort has positioned electrochemical processing among the most sophisticated processing technologies employed in the microelectronics industry today. Electrochemical processing has thus become an integral part of advanced wafer processing and an enabling technology for nanofabrication. In this review we begin with a brief discussion of the phenomenal advances in IC based electronics and Moore's law as indicators of the paradigm shifts in microelectronics. We then highlight the important role played by electrochemical processing in the electronics industry. A detailed discussion of the dual Damascene plating technology and electroplated C4 technology form the key elements of the review. Finally, the challenges and opportunities offered by these technologies in extending Moore's law are discussed.

More »»

2007

Journal Article

Dr. Madhav Datta, Lin, E., Choi, H. - W., McMaster, M., Brewer, R., Werner, D., Hom, J., Upadhya, G., Gopalakrishnan, S., and Rebarber, F., “Liquid Cooling System for Advanced Microelectronics”, ECS Transactions, vol. 6, pp. 13–31, 2007.[Abstract]


Heat removal from advanced microelectronic devices is becoming a major packaging challenge. Thermal management solutions such as microchannel liquid cooling are now becoming commercially available. The use of a liquid cooling system is attractive because of higher heat transfer coefficients or lower thermal resistance as compared to traditional heat pipe or heat sink solutions. In this paper we present a description of the key features of Cooligy's closed loop Liquid Cooling System (LCS). Two key components of the LCS, namely a microheat exchanger and an electrokinetic pump are discussed in detail. Published literature on advanced thermal interface materials and nanofluids are briefly reviewed. Wherever applicable, the importance and impact of electrochemical processing and materials aspects are highlighted.

More »»

2003

Journal Article

Dr. Madhav Datta, “Electrochemical processing technologies in chip fabrication: challenges and opportunities”, Electrochimica acta, vol. 48, pp. 2975–2985, 2003.[Abstract]


Cost-performance advantage of electrochemical processing technologies has enabled a paradigm shift in chip making. The dual Damascene process for Cu chip metallization and the C4 (flip-chip) technology for area array chip-package interconnection have placed electrochemical technologies among the most sophisticated fab processing technologies. These processing technologies have now been integrated into 300 mm wafer processing facilities for chip fabrication. New materials and processes are continuously being developed to meet the microprocessor industry's increasing performance and miniaturization trends. Electromigration issues, and the need for novel polishing approaches to integrate ultra low-k dielectric materials with Cu metallization are some of the immediate concerns in chip making. Development of a compliant, cost-effective Pb-free C4 chip-package interconnection is another key objective of the microelectronics industry, which is making an effort to market Pb-free products in few years. All of these developments provide ample opportunities for electrochemical processing technologies.

More »»

2002

Journal Article

Dr. Madhav Datta, “Micromachining by electrochemical dissolution”, Micromachining of Engineering Materials, McGeough, J.A., editor, Marcel Dekker Inc., , p. 239, 2002.

2000

Journal Article

Dr. Madhav Datta and Landolt, D., “Fundamental aspects and applications of electrochemical microfabrication”, Electrochimica acta, vol. 45, pp. 2535–2558, 2000.[Abstract]


The theory and applications of electrochemical microfabrication technology are reviewed focusing on electrodeposition and dissolution processes. Electrochemical microfabrication offers some unique advantages over competing vapor phase technologies and therefore finds increasing use in the electronics and microsystems industries. The present paper discusses the underlying principles of electrochemical microfabrication processes. The important role of mass transport and current distribution is stressed and it is shown how numerical modeling contributes to the present understanding of critical process parameters. The application of electrochemical microfabrication technology in the electronics industry is illustrated with selected examples.

More »»

2000

Journal Article

Dr. Madhav Datta, Atluri, V., Lee, K., Stevenson, K., Tadayon, P., Jones, M., and Berry, M., “Integration of Pb-free Flip-Chip Bumping Process”, Intel Assembly and Test Technology Journal, pp. 247-258, 2000.

1998

Journal Article

Dr. Madhav Datta, Andreshak, J. C., Romankiw, L. T., and Vega, L. F., “Surface Finishing of High Speed Print Bands I. A Prototype Tool for Electrochemical Microfinishing and Character Rounding of Print Bands”, Journal of The Electrochemical Society, vol. 145, pp. 3047–3051, 1998.[Abstract]


A prototype tool is described for electrochemical surface finishing of an anodic workpiece in strip form, such as the stainless steel print bands used in high speed printers. The tool consists of two units, an electropolishing unit for microfinishing of print bands, and a directional electroetching assembly to provide rounding of characters in the print band. The prototype tool is completely automated and has provisions for rinsing and drying of the mounted print band. Buffed and unbuffed print band samples were used for process development and feasibility testing of the tool. Results demonstrated that the described electrolytic process yields reproducible mirror‐finished print band surfaces with desired leading and trailing edges of characters. The process is applicable either as a complement to traditional buffing to give a final microfinish to print bands, or it can replace the presently used buffing technique for character rounding and surface finishing.

More »»

1998

Journal Article

Dr. Madhav Datta and Romankiw, L. T., “Surface Finishing of High Speed Print Bands II. An Electrochemical Process for Microfinishing of Hardened Fe-13Cr Stainless Steel”, Journal of The Electrochemical Society, vol. 145, pp. 3052–3057, 1998.[Abstract]


An electrochemical process has been developed to obtain microfinishing of hardened Fe‐13Cr stainless steel. The electrolyte is a mixture of phosphoric acid, sulfuric acid, and glycerol. Optimum conditions have been determined that lead to mirror finishing of the work piece over a wide range of current density. The process operates at ambient temperature and is insensitive to slight variations in temperature of the electrolyte. The beneficial effects of glycerol is due to its influence on the transport properties of the electrolyte and the diffusing species. The process is suitable for surface finishing of high speed print bands.

More »»

1998

Journal Article

Dr. Madhav Datta, “Applications of electrochemical microfabrication: An introduction”, IBM journal of research and development, vol. 42, pp. 563–566, 1998.[Abstract]


Global competitive pressures and the ever-increasing demand for faster, smaller, less expensive electronic systems have produced fundamental changes in processing technologies. A variety of microelectronic components are manufactured with high-yield, cost-effective electrochemical processing. Electrochemical microfabrication uses electrochemical methods to create thin- and thick-film-patterned microstructures.

More »»

1998

Journal Article

Dr. Madhav Datta, “Microfabrication by electrochemical metal removal”, IBM journal of research and development, vol. 42, pp. 655–670, 1998.[Abstract]


Recent advances in the development of electrochemical metal-removal processes for microfabrication are reviewed in this paper. After a brief description of the process, several important parameters are identified that determine the material-removal rate, shape control, surface finishing, and uniformity. The influence of surface film properties, mass transport, and current distribution on microfabrication performance are discussed. Several examples of microelectronic component fabrication are presented. These examples demonstrate the challenges and opportunities offered by electrochemical metal removal in microfabrication.

More »»

1997

Journal Article

Dr. Madhav Datta and Harris, D., “Electrochemical micromachining: An environmentally friendly, high speed processing technology”, Electrochimica Acta, vol. 42, pp. 3007–3013, 1997.[Abstract]


Wet chemical etching processes are employed in the manufacturing of a variety of microelectronic components. These processes use etchants that generally contain aggressive and toxic chemicals, generate hazardous waste and have limited resolution. Electrochemical metal removal is an evolving alternate processing technique that involves controlled metal shaping by an external current, thereby requiring less aggressive and nontoxic electrolytes. The application of controlled electrochemical metal removal in the fabrication of microstructures and microcomponents is referred to as electrochemical micromachining (EMM). In this paper a recently developed EMM process and tool for metal mask fabrication is discussed. EMM performance is compared to that obtained by the conventional chemical etching process. Obtained results demonstrate the opportunities offered by EMM particularly as a high-speed, environmentally friendly processing technology.

More »»

1996

Journal Article

R. V. Shenoy and Dr. Madhav Datta, “Effect of Mask Wall Angle on Shape Evolution during Through-Mask Electrochemical Micromachining”, Journal of the Electrochemical Society, vol. 143, pp. 544–549, 1996.[Abstract]


A mathematical model to predict shape evolution during through‐mask electrochemical micromachining (EMM) has been developed. Boundary element method has been used to solve the Laplace equation for electric potential with appropriate boundary conditions that describe the metal dissolution process under ohmic control. The influence of mask wall angle on shape of the evolving cavity, current distribution within the cavity and etch factor have been determined. For mask wall angles less than 90°, the etch factor increased due to the shadowing effect of the mask, whereas the etch factor decreased for mask wall angles greater than 90°. The influence of mask wall angle has been found to diminish with increasing metal film thickness.

More »»

1996

Journal Article

Dr. Madhav Datta, Shenoy, R. V., and Romankiw, L. T., “Recent advances in the study of electrochemical micromachining”, Journal of Manufacturing Science and Engineering, vol. 118, pp. 29–36, 1996.[Abstract]


The present paper reviews some fundamental aspects related to the understanding of the high rate anodic dissolution processes and their influence on thin film patterning by electrochemical micromachining. The role of convective mass transport and current distribution on the surface finish and shape evolution is discussed. Several examples of the applications of maskless and through-mask electrochemical micromachining are presented.

More »»

1996

Journal Article

R. V. Shenoy, Dr. Madhav Datta, and Romankiw, L. T., “Investigation of Island Formation during Through-Mask Electrochemical Micromachining”, Journal of the Electrochemical Society, vol. 143, pp. 2305–2309, 1996.[Abstract]


Shape evolution during through‐mask electrochemical micromachining was investigated to study the problem of island formation caused by loss of electrical contact. A mathematical model was developed to predict shape evolution. Laplace's equation for potential was solved using the boundary element method to determine current distribution at the anode. The current distribution was combined with a moving boundary algorithm to predict the shape of the evolving cavity. The influence of the photoresist artwork dimensions on current distribution at the surface of an evolving feature was investigated. The island formation problem was identified as most likely to occur with a combination of low aspect ratio and low film thickness ratio. Elimination of the island formation problem is discussed.

More »»

1995

Journal Article

Dr. Madhav Datta, “Electrochemical Micromachining: Opportunities and Challenges”, The Electrochemical Society Interface, vol. 4, no. 2, p. 32, 1995.

1995

Journal Article

Dr. Madhav Datta, Shenoy, R. V., Jahnes, C., Andricacos, P. C., Horkans, J., Dukovic, J. O., Romankiw, L. T., Roeder, J., Deligianni, H., Nye, H., Agarwala, B., Tong, H. M., and Totta, P., “Electrochemical fabrication of mechanically robust PbSn C4 interconnections”, Journal of the Electrochemical Society, vol. 142, pp. 3779–3785, 1995.[Abstract]


Electrochemical fabrication of Formula C4s (controlled collapse chip connection) offers significant cost, reliability, and environmental advantages over the currently employed evaporation technology. A continuous seed layer is required for through‐mask electrodeposition of the solder alloy. This layer becomes the ball limiting metallurgy (BLM) for the solder pad after etching. The seed layer metallurgy and the BLM etching are crucial to obtaining mechanically robust C4s. In the present study, the issues related to the selection of seed layer metallurgy, uniformity of plating and etching, and mechanical integrity of C4s have been investigated. The results demonstrate the feasibility of electrochemically fabricating highly reliable Formula structures with a high degree of dimensional uniformity on a variety of wafer sizes ranging up to 200 mm.

More »»

1995

Journal Article

Dr. Madhav Datta, “Fabrication of an array of precision nozzles by through-mask electrochemical micromachining”, Journal of the Electrochemical Society, vol. 142, pp. 3801–3805, 1995.[Abstract]


Through‐mask electrochemical micromachining (EMM) has been employed to fabricate an array of precision nozzles in metal foils for application in inkjet printer heads. An experimental investigation has been conducted to determine the optimum dissolution condition that provides nozzles of desired shape and smooth surfaces. Dissolution below the limiting current yielded irregularly shaped nozzles with extremely rough surfaces while nozzles of desired shape with microsmooth surfaces were obtained by dissolving at the limiting current plateau or at higher voltages. Use of pulsating voltage (current) provided a better control over the nozzle fabrication process because of the possibility of applying high instantaneous current density while maintaining a low average current which is desirable for thin‐film processing. The results of the present study demonstrate the feasibility of employing a through‐mask EMM process for fabricating high precision nozzles in copper and stainless steel foils.

More »»

1994

Journal Article

C. Narayan, Fenton, J., and Dr. Madhav Datta, “Greener materials and manufacturing processes”, Processing of Advanced Materials(UK), vol. 4, pp. 221–228, 1994.

1993

Journal Article

Dr. Madhav Datta, “Anodic dissolution of metals at high rates”, IBM Journal of Research and Development, vol. 37, pp. 207–226, 1993.[Abstract]


Electrochemical metal shaping and finishing processes involve anodic dissolution of metals at high rates. This paper presents a review of some fundamental aspects related to the understanding of such processes. Included are discussions of the phenomena of passive film breakdown that lead to the transpassive dissolution of metals, some of the available information on anodic reaction stoichiometry, and the role of convective mass transport and salt precipitation layers on metal removal rate and surface finish. The use of pulsating current permits the altering of anodic mass transport rates and transpassive dissolution behavior, thereby making it possible to obtain high dissolution efficiencies even at low average current densities.

More »»

1992

Journal Article

Dr. Madhav Datta, Vega, L. F., Romankiw, L. T., and Duby, P., “Mass transport effects during electropolishing of iron in phosphoric-sulfuric acid”, Electrochimica acta, vol. 37, pp. 2469–2475, 1992.[Abstract]


Anodic dissolution of iron in a mixture of phosphoric and sulfuric acids has been investigated using a rotating disk electrode. Potentiostatic and potentiodynamic anodic polarization studies were performed to determine experimental conditions that lead to electropolishing. Results indicate that the onset of electropolishing corresponds to a mass transport controlled limiting current plateau. An appreciable change in the water content of the electrolyte had little influence on the measured limiting current. On the other hand, addition of small amounts of Fe3+ ions in the electrolyte tremendously reduced the limiting current. These data strongly suggest that electropolishing is due to formation of a salt layer at the anode that involves rate limiting transport of dissolved Fe3+ ions from the anode surface into the bulk electrolyte.

More »»

1992

Journal Article

Q. Lin, Sheppard, K. G., Dr. Madhav Datta, and Romankiw, L. T., “Laser-Enhanced Electrodeposition of Lead-Tin Solder”, Journal of The Electrochemical Society, vol. 139, pp. L62–L63, 1992.[Abstract]


Localized, maskless electrodeposition of lead‐tin solder from a sulfonate electrolyte has been achieved by means of laser enhancement. Well defined spots and lines with good surface morphology have been deposited on copper and nickel substrates. This is possible because the laser is found to reduce the deposition overpotential on these substrates.

More »»

1990

Journal Article

E. Rosset, Dr. Madhav Datta, and Landolt, D., “Electrochemical dissolution of stainless steels in flow channel cells with and without photoresist masks”, Journal of applied electrochemistry, vol. 20, pp. 69–76, 1990.[Abstract]


High rate anodic dissolution of Fe, Fe13Cr, Fe24Cr, Cr and AISI type 304 stainless steel is studied in NaCl and NaNO3 using a flow channel cell with well-defined hydrodynamic conditions. The apparent valence for dissolution and the surface finish are investigated as a function of current density. Electrochemical etching experiments through photoresist masks are performed with type 304 stainless steel using NaNO3. The influence of current density on the shape and surface finish of the etch grooves and the uniformity of the attack between differently spaced grooves can be qualitatively explained from the electrochemical data obtained on flat electrodes.

More »»

1990

Journal Article

Dr. Madhav Datta and Vercruysse, D., “Transpassive dissolution of 420 stainless steel in concentrated acids under electropolishing conditions”, Journal of The Electrochemical Society, vol. 137, pp. 3016–3023, 1990.[Abstract]


Anodic dissolution of 420 stainless steel (Fe‐13Cr alloy) in concentrated phosphoric acid, sulfuric acid, and their mixtures has been studied to determine the conditions that lead to electropolishing of the alloy in these electrolytes. A rotating disk electrode system has been employed to study the influence of electrolyte composition, electrode rotation speed, and electrolyte temperature on anodic polarization behavior and the surface finish. Anodic polarization curves in these electrolytes show active‐passive‐transpassive transitions. Concentrated sulfuric acid is found to be unsuitable for electro‐polishing, since metal dissolution is insignificant in this electrolyte, even at very high anode potentials. In phosphoric acid and a mixture of phosphoric and sulfuric acids, electropolishing is observed in the transpassive potential region at or beyond a limiting current plateau. At 90°C, the measured limiting current densities as a function of the rotation speed follow Levich behavior, while at 25°C and 60°C, convective mass transport effects are masked by surface kinetic steps. Highly reflecting and microsmooth surfaces are obtained under conditions where the dissolution reaction is mass transport‐controlled.

More »»

1989

Journal Article

Dr. Madhav Datta and Romankiw, L. T., “Application of chemical and electrochemical micromachining in the electronics industry”, Journal of the Electrochemical Society, vol. 136, p. 285C–292C, 1989.[Abstract]


This paper discusses the principal applications of chemical and electrochemical micromachining to fabrication of electronic components. Some of the recently investigated techniques for maskless micromachining are also presented. Chemical micromachining is widely used in the present day electronics industry for a variety of applications including fabrication of metallic parts, printed circuit boards, and semiconductor devices. Electrochemical micromachining, on the other hand, appears to be very promising as a future micromachining technique since in many areas of application it offers several advantages that include higher machining rate, better precision and control, and a wider range of materials that can be machined.

More »»

1989

Journal Article

Dr. Madhav Datta, Romankiw, L. T., Vigliotti, D. R., and Von Gutfeld, R. J., “Jet and Laser-Jet Electrochemical Micromachining of Nickel and Steel”, Journal of the Electrochemical Society, vol. 136, pp. 2251–2256, 1989.[Abstract]


Experimental results on jet and laser‐jet electrochemical micromachining of nickel and steel in neutral solutions of sodium chloride and sodium nitrate are reported. In the absence of a laser beam, a nitrate solution is better suited for micromachining at high current densities, since it yields high machining rates and relatively low overcutting. In the presence of a laser beam, however, nitrate solution is found to be unsuitable for micromachining, since oxygen evolution is the dominant anodic reaction even at high current densities. In chloride solution, on the other hand, metal dissolution reaction is independent of laser power, but the laser beam helps in focusing the applied current into the machining area thereby increasing the effective machining rate and precision.

More »»

1988

Journal Article

R. J. Von Gutfeld, Vigliotti, D. R., and Dr. Madhav Datta, “Laser chemical etching of metals in sodium nitrate solution”, Journal of applied physics, vol. 64, pp. 5197–5200, 1988.[Abstract]


A focused cw argon‐ion laser has been used to etch several metals, including copper,molybdenum,nickel,niobium, and stainless steel in a 0.5Msodium nitrate neutral salt solution. Exceedingly smooth etch surfaces have been obtained for several of these metals with etch rates as high as 4 μm/s. Experiments were carried out as a function of laser intensity and laser dwell time to etch arrays of small holes, 100 μm or less in diameter on the different samples. From experiments performed in water under similar laser conditions we conclude that melt or near‐melt temperatures are required to obtain etching in the salt solution. A comparison of the power required to produce incipient etching is made with calculated temperatures obtained for similar powers using a theory which approximates the experimental conditions. These calculated temperatures are reasonably close to the melt temperatures for most cases and offer supporting evidence for our etching model.

More »»

1987

Journal Article

L. Ponto, Dr. Madhav Datta, and Landolt, D., “Electropolishing of iron-chromium alloys in phosphoric acid-sulphuric acid electrolytes”, Surface and Coatings Technology, vol. 30, pp. 265–276, 1987.[Abstract]


The electropolishing of iron, the ferritic iron-chromium alloys, Fe-13Cr and Fe-24Cr, and austenitic type 304 stainless steel has been investigated in H3PO4-H2SO4 electrolytes using rotating disk electrodes. The electropolishing of stainless-steel-type alloys takes place in the transpassive region and is mass transport controlled. It is favoured by high temperatures. The anodic polarization of the Fe-Cr alloys in 65% H3PO4-20% H2SO4-15% H2O is insensitive to the elemental composition of the alloy and is the same as for the austenitic type 304 stainless steel. At 70°C electropolishing is obtained for a wide concentration range of H3PO4-H2SO4, but in the absence of H3PO4, iron passivity prevents the establishment of electropolishing conditions.

More »»

1987

Journal Article

Dr. Madhav Datta, Romankiw, L. T., Vigliotti, D. R., and Von Gutfeld, R. J., “Laser etching of metals in neutral salt solutions”, Applied physics letters, vol. 51, pp. 2040–2042, 1987.[Abstract]


We report new findings that relate to rapid maskless laser etching of steel and stainless steel in neutral solutions of sodium chloride, sodium nitrate, and potassium sulfate. Etch rates have been determined as a function of laser power, laser on‐time, and solution concentration. The morphology of laser‐etched holes obtained in these solutions was compared with holes obtained in pure water. Results indicate that some controlled melting occurs under certain laser conditions in addition to the metal dissolution process induced by the locally intense heat of the laser beam.

More »»

1985

Journal Article

H. J. Mathieu, Dr. Madhav Datta, and Landolt, D., “Thickness of natural oxide films determined by AES and XPS with/without sputtering”, Journal of vacuum science & technology A, vol. 3, pp. 331–335, 1985.[Abstract]


The thickness of natural air‐formed oxides on Al, Si, Fe, Ni, and Ta is determined by Auger electron spectroscopy (AES), depth profiling, and angle‐resolved photoelectron spectroscopy (XPS). The sputter rate of the oxides is measured under the same conditions and their values are given with respect to a certified standard 100 nm Ta 2O5 reference. Data from AES depth profiling are corrected for the influence of the electron mean free path. XPS data are evaluated from area intensities of the bands after peak synthesis (fitting). Using literature values of mfp for oxides, their thickness is evaluated. AES and XPS data are in reasonable agreement giving oxide thickness ranging from 0.2 to 5 nm increasing in the order of SiO2<NiO<Al2O5<Fe2O3.

More »»

1985

Journal Article

Dr. Madhav Datta and Landolt, D., “Experimental investigation of mass transport in pulse plating”, Surface technology, vol. 25, pp. 97–110, 1985.[Abstract]


Mass transport during the electrodeposition of copper from acidified sulphate solution using single and multiple pulses was studied. Experimental results obtained in a diffusion cell and with a rotating hemispherical electrode are compared with published theoretical calculations of various degrees of mathematical sophistication and complexity. The simple duplex diffusion-layer model proposed by Ibl gives adequate values of the pulse limiting current density for many practical purposes. The agreement with experiment can be further improved by using a semi-empirical modification of the model.

More »»

1985

Journal Article

Dr. Madhav Datta, Rosset, E., and Landolt, D., “Pulse Polishing of Die Steels in Neutral Salt Solutions”, Plat. & Surf. Finishing, vol. 72, p. 60, 1985.

1985

Journal Article

O. Chene, Dr. Madhav Datta, and Landolt, D., “Electrodeposition of Copper by Pulsating Current: Influence of Mass Transport on the Morphology and the Uniformity of Deposits”, Oberflache-Surface, vol. 26, p. 45, 1985.

1984

Journal Article

Dr. Madhav Datta, Mathieu, H. J., and Landolt, D., “Characterization of transpassive films on nickel by sputter profiling and angle resolved AES/XPS”, Applications of Surface Science, vol. 18, pp. 299–314, 1984.[Abstract]


Auger Electron Spectroscopy and X-ray Photoelectron Spectroscopy were applied to the study of thin films formed by transpassive dissolution of nickel in a nitrate electrolyte and by exposure of mechanically polished nickel to air. Variation of take-off angle and sputter profiling were used to determine the thickness and chemical composition of these films. Transpassive films are found to be thicker and different in composition than air formed films. Nitrogen present in the metal-oxide interface of the transpassive film is in a reduced state.

More »»

1984

Journal Article

C. Clerc, Dr. Madhav Datta, and Landolt, D., “On the theory of anodic levelling: model experiments with triangular nickel profiles in chloride solution”, Electrochimica acta, vol. 29, pp. 1477–1486, 1984.[Abstract]


<p>The influence of profile height and orientation on the rate of anodic levelling was studied under controlled masstransport conditions in a flow cell using triangular shaped profiles made of nickel in a NaCl electrolyte. Experimental conditions were chosen so that levelling was carried out well below, close to and well above the limiting current for salt precipitation and results were compared to those predicted from theoretical calculations using FEM. It is found that the rate of levelling of microprofiles under limiting current conditions is independent of flow direction and corresponds to that theoretically predicted for primary or tertiary current distribution. The levelling of macroprofiles at the limiting current is slower and depends on flow direction. Levelling above the limiting current is mass transport controlled. For macroprofiles oriented parallel to flow direction, levelling is slower above the limiting current than at the limiting current.</p>

More »»

1984

Journal Article

Dr. Madhav Datta, Mathieu, H. J., and Landolt, D., “AES/XPS study of transpassive films on iron in nitrate solution”, Journal of The Electrochemical Society, vol. 131, pp. 2484–2489, 1984.[Abstract]


Anodic films on iron formed in a forced convection system in the transpassive potential region in nitrate electrolytes at current densities up to 40 A/cm2 have been studied by in situ coulometry and ex situ Auger electron spectroscopy (AES) and angle‐resolved x‐ray photoelectron spectroscopy (XPS). Qualitatively similar results on the variation of film thickness with applied current density are obtained by different methods. The transition from transpassive oxygen evolution to transpassive metal dissolution coincides with a marked decrease in film thickness and with the appearance of nitrogen in a reduced state at the metal‐film interface.

More »»

1983

Journal Article

Dr. Madhav Datta and Landolt, D., “Electrochemical saw using pulsating voltage”, Journal of applied electrochemistry, vol. 13, pp. 795–802, 1983.[Abstract]


An electrochemical process for cutting metals and conducting refractory materials using a pulsating voltage has been developed. A laboratory type electrochemical saw is described which has been successfully applied to cut different metals and sintered V2O3. The influence of different operating variables on cutting rate and precision has been studied for the cutting of nickel in a nitrate electrolyte.

More »»

1983

Journal Article

Dr. Madhav Datta, Giovanola, B., and Kolub, J. L., “Selective dissolution of dendritic or interdendritic phase in Sn-Al alloys”, Practical Metallography, vol. 20, pp. 394–405, 1983.

1982

Journal Article

Dr. Madhav Datta and Landolt, D., “High rate transpassive dissolution of nickel with pulsating current”, Electrochimica Acta, vol. 27, pp. 385–390, 1982.[Abstract]


The influence of pulsating current on high rate transpassive dissolution of nickel in 6 M NaNO3 has been investigated. Obtained results indicate that current efficiency for nickel dissolution is influenced by pulse time and to a certain extent by relaxation time and is related to the anion build up at the anode. Dissolution efficiency for a given average current density is higher under pulsating current than direct current conditions. The influence of different pulse parameters on the anode potential and on the onset of sparking are investigated. The use of a pulsating current provides additional possibilities to influence the transpassive dissolution behavior in electrochemical machining and surface finishing operations.

More »»

1982

Journal Article

Dr. Madhav Datta and Landolt, D., “Pit and flow streak formation during high rate dissolution of nickel”, Journal of The Electrochemical Society, vol. 129, pp. 1889–1895, 1982.[Abstract]


Pit and flow streak formation during high rate dissolution of nickel in chloride solution has been investigated. Experiments were carried out under active and transpassive dissolution conditions using direct and pulsating current. The results obtained indicate that sulfide inclusions are the nucleation sites of pits. The growth, size distribution, and life cycle of pits are governed by the size of inclusions and their number and by dissolution conditions. Characteristic tails and flow streaks observed during transpassive dissolution with direct current are due to local disturbance of hydrodynamic conditions introduced by the presence of pits.

More »»

1981

Journal Article

Dr. Madhav Datta and Landolt, D., “Electrochemical machining under pulsed current conditions”, Electrochimica acta, vol. 26, pp. 899–907, 1981.[Abstract]


The possibility of using pulsed current in electrochemical machining at low electrolyte flow rate has been investigated. Theoretical aspects of predicting electrolyte heating and limiting rate of mass transport are discussed in terms of simplified models. High rate dissolution of nickel in sodium chloride solutions under pulsed current conditions was investigated in a flow channel cell by studying the influence of different pulse parameters on anode potential, surface microtexture, surface roughness and current efficiency of metal dissolution. Obtained results indicate that anode potential and surface finish are controlled by mass transport in agreement with steady state behavior. Maximum current density applicable under pulsed current conditions is limited by the occurrence of sparking.

More »»

1980

Journal Article

Dr. Madhav Datta and Landolt, D., “On the role of mass transport in high rate dissolution of iron and nickel in ECM electrolytes—I. Chloride solutions”, Electrochimica Acta, vol. 25, pp. 1255–1262, 1980.[Abstract]


High rate anodic dissolution of iron and nickel in 5 M NaCl was studied in a flow channel cell under controlled hydrodynamic conditions. Galvanostatic experiments were aimed at investigating the influence of current density and electrolyte flow rate on anode potential, current efficiency for metal dissolution and surface texture resulting from dissolution. Active dissolution at low current densities leads to surface etching and transpassive dissolution at high current densities leads to surface brightening. Transition from active to transpassive dissolution is mass transport controlled and is accompanied by a change in anode potential, surface microtexture and in case of iron by a change in the valence of metal dissolution.

More »»

1980

Journal Article

Dr. Madhav Datta and Landolt, D., “On the role of mass transport in high rate dissolution of iron and nickel in ECM electrolytes—II. Chlorate and nitrate solutions”, Electrochimica Acta, vol. 25, pp. 1263–1271, 1980.[Abstract]


Transpassive dissolution of iron and nickel in 5 M NaClO3 and 6 M NaNO3 has been investigated in a flow channel cell allowing for controlled hydrodynamic conditions. Applied current density ranged up to 33 A/cm2, applied flow rates up to 1760 cm/s. The influence of mass transport on current efficiency for metal dissolution, apparent anode potential and surface microtextures resulting from dissolution was investigated. Obtained results confirm that all these parameters are influenced by mass transport processes but secondary effects such as gas evolution, hydroxide precipitation, homogeneous chemical reactions, or joule beating in many cases interfere with convective transport phenomena in the solution. Optimisation of ECM operating conditions and modelling for tool design applications require intimate knowledge of the influence of hydrodynamic conditions on the electrochemical behavior of the metal-electrolyte combination employed.

More »»

1979

Journal Article

Dr. Madhav Datta, Mathieu, H. J., and Landolt, D., “Anodic film studies on nickel under high rate transpassive dissolution conditions”, Electrochimica Acta, vol. 24, pp. 843–850, 1979.[Abstract]


Coulometry and Auger Electron Spectroscopy (AES) were employed to study thickness and composition of anodic films formed on nickel under high rate transpassive dissolution conditions. Nickel anodes were polarized at constant current densities up to 30 A/cm2 in alkaline nitrate electrolytes of different nitrate and hydroxyl ion concentration using a flow channel cell with a constant electrolyte flow velocity of 10m/sec. Results show that with increasing current density film thickness goes through a maximum. Nitrogen is detected at the apparent film metal interface in the current region where metal dissolution occurs. No correlation between anodic film thickness and dissolution efficiency is found. The data, together with previous observations, suggest that high rate transpassive dissolution takes place from film free sites.

More »»

1978

Journal Article

Dr. Madhav Datta and Landolt, D., “Influence of Organic Additives on the Electrochemical Machining of Metals”, Oberflache-Surface, vol. 19, p. 159, 1978.

1977

Journal Article

Dr. Madhav Datta and Landolt, D., “On the influence of electrolyte concentration, pH and temperature on surface brightening of nickel under ECM conditions”, Journal of Applied Electrochemistry, vol. 7, pp. 247–252, 1977.[Abstract]


High rate anodic dissolution of nickel in sodium nitrate electrolytes was studied under controlled hydrodynamic conditions in order to investigate the influence of electrolyte concentration, pH and temperature on surface brightening under conditions comparable to electrochemical machining. Dissolution experiments were performed on a rectangular flow channel cell through which the electrolyte was pumped at a constant linear velocity of 1000 cm s−1. Results show that the onset of surface brightening depends on concentration and temperature of the electrolyte but is little affected by pH. The data are consistent with a previously described salt precipitation model for surface brightening.

More »»

1977

Journal Article

Dr. Madhav Datta and Landolt, D., “Film breakdown on nickel under transpassive dissolution conditions in sodium nitrate solutions”, Journal of the Electrochemical Society, vol. 124, pp. 483–489, 1977.[Abstract]


Film breakdown phenomena leading to transpassive high rate dissolution of nickel in nitrate electrolytes were investigated under controlled flow conditions. Current efficiencies for metal dissolution were determined as a function of current density at different pH, temperature, and nitrate ion concentration. Initiation of film breakdown was investigated by performing experiments at very small dissolution times using polycrystalline and single crystal anodes and observing the resulting surface textures by means of optical and scanning electron microscopes. Results indicate that during high rate nickel dissolution, current efficiency is mostly governed by anode potential and nitrate ion concentration while bulk electrolyte pH and temperature have relatively little effect. Transpassive dissolution is initiated by local breakdown of the passive film. Dissolution takes place at the activated sites from a few well‐defined crystal planes. With increasing time, these sites grow until they merge together resulting in an etched surface microtexture. Similarities between observed film breakdown phenomena leading to high rate dissolution at potentials above those for oxygen evolution and the pitting behavior of passive metals under corrosion conditions are discussed.

More »»

1975

Journal Article

Dr. Madhav Datta and Landolt, D., “Surface brightening during high rate nickel dissolution in nitrate electrolytes”, Journal of the Electrochemical Society, vol. 122, pp. 1466–1472, 1975.[Abstract]


Conditions leading to surface brightening during ECM in passivating electrolytes were investigated by studying high rate transpassive nickel dissolution in acidified nitrate electrolytes under controlled hydrodynamic conditions. The experimental apparatus consisted of a flow channel cell in which constant electrolyte linear velocities between 100 and 1760 cm/sec could be reached. Dissolution experiments were performed galvanostatically at current densities ranging from 0.5 to 30 A/cm2. Over‐all current voltage behavior, current efficiency for metal dissolution and surface appearance were evaluated as a function of applied current density, flow rate, and electrolyte composition. Results indicate that the onset of surface brightening is mass transfer controlled and coincides with the formation of a salt precipitation layer at the anode.

More »»

1973

Journal Article

Dr. Madhav Datta and Landolt, D., “Stoichiometry of anodic nickel dissolution in NaCl and NaClO 3 under active and transpassive conditions”, Corrosion Science, vol. 13, pp. 187–197, 1973.[Abstract]


The anodic dissolution of nickel 200 at very high current densities has been investigated in 1N NaClO2, 1N NaCl and in mixtures of the two electrolytes by measuring potentiostatic current potential curves and by determining the current efficiency for metal dissolution from weight loss measurements. In 1N NaCl Tafel behavior was found up to 0·5 A/cm2. In 1N NaClO3 no active dissolution region was observed, but substantial transpassive dissolution occurred at current densities above 2 A/cm2. The presence of chloride ions led to pitting and to an increase in anodic dissolution rate. Apparent current efficiencies based on divalent nickel formation even exceeded 100 per cent, indicating that the chlorate ion was decomposed at the anode.

More »»

Publication Type: Patent

Year of Publication Publication Type Title

2015

Patent

Dr. Madhav Datta, Emory, D., Joshi, S. M., Menezes, S., and Suh, D., “Copper-containing C4 ball-limiting metallurgy stack for enhanced reliability of packaged structures and method of making same”, U.S. Patent US 12/655,9752015.[Abstract]


The invention relates to a ball-limiting metallurgy stack for an electrical device that contains at least one copper layer disposed upon a Ti adhesion metal layer. The ball-limiting metallurgy stack resists Sn migration toward the upper metallization of the device.

More »»

2012

Patent

Dr. Madhav Datta, Leong, B., and McMaster, M., “Microheat exchanger for laser diode cooling”, U.S. Patent US 12/536,3612012.[Abstract]


A microheat exchanging assembly is configured to cool one or more heat generating devices, such as integrated circuits or laser diodes. The microheat exchanging assembly includes a first ceramic assembly thermally coupled to a first surface, and in cases, a second ceramic assembly thermally coupled to a second surface. The ceramic assembly includes one or more electrically and thermally conductive pads to be thermally coupled to a heat generating device, each conductive pad is electrically isolated from each other. The ceramic assembly includes a ceramic layer to provide this electrical isolation. A top surface and a bottom surface of the ceramic layer are each bonded to a conductive layer, such as copper, using an intermediate joining material. A brazing process is performed to bond the ceramic layer to the conductive layer via a joining layer. The joining layer is a composite of the joining material, the ceramic layer, and the conductive layer.

More »»

2012

Patent

Dr. Madhav Datta and McMaster, M., “Bonded metal and ceramic plates for thermal management of optical and electronic devices”, U.S. Patent US 12/536,4022012.[Abstract]


A ceramic assembly includes one or more electrically and thermally conductive pads to be thermally coupled to a heat generating device, each conductive pad is electrically isolated from each other. The ceramic assembly includes a ceramic layer to provide this electrical isolation. The ceramic layer has high thermal conductivity and high electrical resistivity. A top surface and a bottom surface of the ceramic layer are each bonded to a conductive layer, such as copper, using an intermediate joining material. A brazing process is performed to bond the ceramic layer to the conductive layer via a joining layer. The joining layer is a composite of the joining material, the ceramic layer, and the conductive layer. The top conductive layer and the joining layer are etched to form the electrically isolated conductive pads. The conductive layers are bonded to the ceramic layer using a bare ceramic approach or a metallized ceramic approach.

More »»

2010

Patent

Dr. Madhav Datta, McMaster, M., Brewer, R., Zhou, P., Tsao, P., Upadhaya, G., and Munch, M., “Method of fabricating high surface to volume ratio structures and their integration in microheat exchangers for liquid cooling system”, U.S. Patent US 11/326,6902010.[Abstract]


An structure and method of manufacturing a microstructure for use in a heat exchanger is disclosed. The heat exchanger comprises a manifold layer and an microstructured region. The manifold layer comprises a structure to deliver fluid to the microstructured region. The microstructured region is formed from multiple windowed layers formed from heat conductive layers through which a plurality of microscaled apertures have been formed by a wet etching process. The plurality of windowed layers are then coupled together to form a composite microstructure.

More »»

2009

Patent

Dr. Madhav Datta, Zhou, P., Choi, H. - W., Leong, B., McMaster, M., and Werner, D. E., “Fabrication of high surface area, high aspect ratio mini-channels and their application in liquid cooling systems”, U.S. Patent US 12/571,2652009.[Abstract]


The present invention provides methods and apparatuses which achieve high heat transfer in a fluid cooling system, and which do so with a small pressure drop across the system. The present invention teaches the use of wall features on the fins of a heat exchanger to cool fluid in a fluid cooling system. The present invention also discloses high aspect ratio, high surface area structures applicable in micro-heat exchangers for fluid cooling systems and cost effective methods for manufacturing the same.

More »»

2007

Patent

Dr. Madhav Datta, Emory, D., Suh, D., Joshi, S. M., and Menezes, S., “Copper-containing C4 ball-limiting metallurgy stack for enhanced reliability of packaged structures and method of making same”, U.S. Patent US 10/776,4482007.[Abstract]


The invention relates to a ball-limiting metallurgy stack for an electrical device that contains at least one copper layer disposed upon a Ti adhesion metal layer. The ball-limiting metallurgy stack resists Sn migration toward the upper metallization of the device.

More »»

2007

Patent

B. Conway, Brewer, R., Tsao, P., Hom, J., Werner, D., Zhou, P., Upadhya, G., Dr. Madhav Datta, Firouzi, A., and Landry, F., “Methodology for the liquid cooling of heat generating components mounted on a daughter card/expansion card in a personal computer through the use of a remote drive bay heat exchanger with a flexible fluid interconnect”, U.S. Patent US 11/800,3032007.[Abstract]


A cooling system includes a cooling unit configured to fit within a single drive bay of a personal computer. The cooling unit includes a fluid-to-air heat exchanger, an air mover, a pump, fluid lines, and control circuitry. The cooling system also includes a cooling loop configured to be coupled to one or more heat generating devices. The cooling loop includes the pump and the fluid-to-air heat exchanger from the cooling unit, and at least one heat exchanger coupled together via flexible fluid lines. The heat exchanger is thermally coupled to the heat generating device. The cooling unit is configured to maintain noise below a specified acoustical specification. To meet this acoustical specification, the size, position, and type of the components within the cooling unit are specifically configured.

More »»

2006

Patent

Dr. Madhav Datta, Zhou, P., Hom, J., Munch, M., and McMaster, M., “Re-workable metallic TIM for efficient heat exchange”, U.S. Patent US 11/345,5562006.[Abstract]


A heat exchanging system uses a metallic TIM for efficient heat transfer between a heat source and a heat exchanger. The heat source is preferably an integrated circuit coupled to a circuit board. The metallic TIM preferably comprises indium. The metallic TIM is comprised of either a separate metallic TIM foil or as a deposited layer of metal material. The metallic TIM foil is mechanically joined to a first surface of the heat exchanger and to a first surface of the integrated circuit by applying sufficient pressure during clamping. Disassembly is accomplished by un-clamping the heat exchanger, the metallic TIM foil, and the integrated circuit from each other. Once disassembled, the heat exchanger and the metallic TIM foil are available to be used again. If the metallic TIM is deposited onto the heat exchanger, disassembly yields a heat exchanging sub-assembly that is also reusable.

More »»

2005

Patent

Dr. Madhav Datta, Emory, D., Joshi, S. M., Menezes, S., and Suh, D., “Copper-containing C4 ball-limiting metallurgy stack for enhanced reliability of packaged structures and method of making same”, U.S. Patent US 09/961,0342005.[Abstract]


The invention relates to a ball-limiting metallurgy stack for an electrical device that contains at least one copper layer disposed upon a Ti adhesion metal layer. The ball-limiting metallurgy stack resists Sn migration toward the upper metallization of the device.

More »»

2005

Patent

P. K. Moon, Ma, Z., and Dr. Madhav Datta, “Under bump metallurgy for Lead-Tin bump over Cu pad”, U.S. Patent US 10/608,4072005.[Abstract]


The present invention describes a method including providing a component, the component having a bond pad; forming a passivation layer over the component; forming a via in the passivation layer to uncover the bond pad; and forming an under bump metallurgy (UBM) over the passivation layer, in the via, and over the bond pad, in which the UBM includes an alloy of Aluminum and Magnesium.
The present invention also describes an under bump metallurgy (UBM) that includes a lower layer, the lower layer including an alloy of Aluminum and Magnesium; and an upper layer located over the lower layer.

More »»

2005

Patent

Dr. Madhav Datta, “Selective ball-limiting metallurgy etching processes for fabrication of electroplated tin bumps”, U.S. Patent US 10/868,1502005.[Abstract]


A ball-limiting metallurgy stack is disclosed for an electrical device that contains at least one copper layer disposed upon a titanium adhesion metal layer. The ball-limiting metallurgy stack resists tin migration toward the upper metallization of the device. An etch process flow is also disclosed which resists the redepostion of the tin during etching of a copper layer.

More »»

2005

Patent

V. M. Dubin, Thomas, C. D., McGregor, P., and Dr. Madhav Datta, “Method of electroless introduction of interconnect structures”, U.S. Patent US 09/753,2562005.[Abstract]


A method comprising introducing an interconnect structure in an opening through a dielectric over a contact point, and introducing a conductive shunt material through a chemically-induced oxidation-reduction reaction. A method comprising introducing an interconnect structure in an opening through a dielectric over a contact point, introducing a conductive shunt material having an oxidation number over an exposed surface of the interconnect structure, and reducing the oxidation number of the shunt. An apparatus comprising a substrate comprising a device having contact point, a dielectric layer overlying the device with an opening to the contact point, and an interconnect structure disposed in the opening comprising an interconnect material and a different conductive shunt material.

More »»

2004

Patent

V. M. Dubin, Thomas, C. D., McGregor, P., and Dr. Madhav Datta, “Interconnect structures and a method of electroless introduction of interconnect structures”, U.S. Patent US 10/290,7762004.[Abstract]


An apparatus including a substrate comprising a device having contact point; a dielectric layer overlying the device with an opening to the contact point; and an interconnect structure disposed in the opening including an interconnect material and a different conductive shunt material.

More »»

2004

Patent

P. K. Moon, Ma, Z., and Dr. Madhav Datta, “Under bump metallurgy for lead-tin bump over copper pad”, U.S. Patent US 10/262,2812004.[Abstract]


The present invention describes a method including providing a component, the component having a bond pad; forming a passivation layer over the component; forming a via in the passivation layer to uncover the bond pad; and forming an under bump metallurgy (UBM) over the passivation layer, in the via, and over the bond pad, in which the UBM includes an alloy of Aluminum and Magnesium.
The present invention also describes an under bump metallurgy (UBM) that includes a lower layer, the lower layer including an alloy of Aluminum and Magnesium; and an upper layer located over the lower layer.

More »»

2004

Patent

Dr. Madhav Datta, Emory, D., Huang, T. -luh, Joshi, S. M., King, C. A., Ma, Z., Marieb, T., Mckeag, M., Suh, D., Yang, S., and , “Thermo-mechanically robust C4 ball-limiting metallurgy to prevent failure due to die-package interaction and method of making same”, U.S. Patent US 09/961,0372004.[Abstract]


The invention relates to a ball limiting metallurgy stack for an electrical device that contains a tin diffusion barrier and thermo-mechanical buffer layer disposed upon a refractory metal first layer. The multi-diffusion barrier layer stack resists tin migration toward the upper metallization of the device.

More »»

2004

Patent

Dr. Madhav Datta, “Selective ball-limiting metallurgy etching processes for fabrication of electroplated tin bumps”, U.S. Patent US 10/279,4782004.[Abstract]


A ball-limiting metallurgy stack is disclosed for an electrical device that contains at least one copper layer disposed upon a titanium adhesion metal layer. The ball-limiting metallurgy stack resists tin migration toward the upper metallization of the device. An etch process flow is also disclosed which resists the redepostion of the tin during etching of a copper layer.

More »»

2003

Patent

Dr. Madhav Datta, Gruber, P. A., Rubino, J. M., Sambucetti, C. J., and Walker, G. F., “Method for testing chips on flat solder bumps”, U.S. Patent US 09/301,8892003.[Abstract]


A method for testing integrated circuit chips with probe wires on flat solder bumps and IC chips that are equipped with flat solder bumps are disclosed. In the method, an IC chip that has a multiplicity of bond pads and a multiplicity of flat solder bumps are first provided in which each of the solder bumps has a height less than ½ of its diameter on the multiplicity of bond pads. The probe wires can thus be easily used to contact the increased target area on the solder bumps for establishing electrical connection with a test circuit. The probe can further be conducted easily with all the Z height of the bumps are substantially equal. The height of the solder bumps may be suitably controlled by either a planarization process in which soft solder bumps are compressed by a planar surface, or solder bumps are formed in an in-situ mold by either a MSS or an electroplating process for forming solder bumps in the shape of short cylinders. When the MSS method is used for planting the bumps, solder bumps are transferred onto the wafer surface in a substantially flattened hemi-spherical shape.

More »»

2001

Patent

P. C. Andricacos, Dr. Madhav Datta, Horkans, W. J., Kang, S. K., Kwietniak, K. T., Mathad, G. S., Purushothaman, S., Shi, L., Tong, H. M., and Deligianni, H., “Flip-chip interconnections using lead-free solders”, U.S. Patent US 08/614,9842001.[Abstract]


An interconnection structure suitable for the connection of microelectronic circuit chips to packages is provided by this invention. In particular, the invention pertains to the area-array or flip-chip technology often called C4 (controlled collapse chip connection). The structure comprises an adhesion/barrier layer deposited on a passivated substrate (e.g., a silicon wafer), optionally an additional adhesion layer, a solderable layer of a metal selected from the group consisting of Ni, Co, Fe, NiFe, NiCo, CoFe and NiCoFe on the adhesion/barrier layer, and a lead-free solder ball comprising tin as the predominate component and one or more alloying elements selected from Bi, Ag, and Sb, and further optionally including one or more elements selected from the group consisting of Zn, In, Ni, Co and Cu.

More »»

2001

Patent

Dr. Madhav Datta, Galasco, R. T., Lehman, L. P., Magnuson, R. H., Susko, R. A., and Topa, R. D., “Removal of metal skin from a copper-Invar-copper laminate”, U.S. Patent US 09/347,5812001.[Abstract]


A method of removing a metal skin from a through-hole surface of a copper-Invar-copper (CIC) laminate without causing differential etchback of the laminate. The metal skin includes debris deposited on the through-hole surface as the through hole is being formed by laser or mechanical drilling of a substrate that includes the laminate as an inner plane. Removing the metal skin combines electrochemical polishing (ECP) with ultrasonics. ECP dissolves the metal skin in an acid solution, while ultrasonics agitates and circulates the acid solution to sweep the metal skin out of the through hole. ECP is activated when a pulse power supply is turned on and generates a periodic voltage pulse from a pulse power supply whose positive terminal is coupled to the laminate and whose negative terminal is coupled to a conductive cathode. After the metal skin is removed, the laminate is differentially etched such that the copper is etched at a faster rate than the Invar. To prevent the differential etching, a copper layer is formed on a surface of the substrate with an electrical resistance R1 between the copper layer and the positive terminal of the pulse power supply. Additionally, an electrical resistance R2 is formed between the laminate and the positive terminal of the pulse power supply. Adjustment of R1 and R2 controls the relative etch rates of the copper and the Invar.

More »»

2001

Patent

E. Israel Cooper, Dr. Madhav Datta, Jr, T. Edward Din, Kanarsky, T. Safron, Pike, M. Barry, and Shenoy, R. Vaman, “Methods for monitoring components in the TiW etching bath used in the fabrication of C4s”, U.S. Patent US 09/138,4422001.[Abstract]


Monitoring techniques have been developed for direct/indirect determination of metal etching bath components and for managing their replenishment. The disclosed methods have been successfully employed to make TiW etching a robust process that provides minimized and controlled undercutting of ball limited metallurgy and mechanical reliable C4s. A metal etching solution is monitored and replenished by measuring the sulfate concentration of a hydrogen peroxide, soluble salt, and soluble EDTA salt etchant. Turbidimetric titration conditions are used to measure and compare opaqueness of liquids by viewing light through them and determining how much light is cut off. Additional sulfate is added to maintain the sulfate concentration. Water and/or fresh etchant is added to compensate for evaporation or drag.

More »»

2001

Patent

J. Michael Cotte, Dr. Madhav Datta, and Kang, S. Kwon, “Reflow of low melt solder tip C4's”, U.S. Patent US 09/359,0612001.[Abstract]


An array of C4 solder bumps and a method for making is described incorporating an array of conductive areas on an electrical device, each conductive area having a layer of ball limited metalurgy at the device surface and two layers of solder having respective melting temperatures to form the C4 structure. The method includes melting the second layer of solder in the down position or towards earth to form a C4 solder ball or bump. The invention overcomes the problem of low temperature solder from wicking over the sidewall surfaces of the high melt solder of the C4 structure and attacking the edges of the underlying seed layers of the ball limited metalurgy.

More »»

2000

Patent

J. M. Cotte and Dr. Madhav Datta, “High performance lithium polymer electrolyte battery”, U.S. Patent US 08/915,1342000.[Abstract]


A primary lithium battery particularly adapted for use in self-contained self-powered devices (SSPD) for mobile communication and computing products, such as radio frequency identification tags, PCMCIA cards, and smart cards. The battery utilizes a solid polymer electrolyte membrane that preferably has a polyacrylonitrile matrix. Performance of the electrolyte membrane is optimized by controlling the amount of aprotic organic solvents within the membrane within a prescribed range of ratios. The battery cathode is encapsulated within a polymeric matrix that eliminates the exposure hazard posed by lithium intercalation compounds used within the cathode. Use of stainless steel foil current collectors gives a high open circuit voltage of 3.8 volts and high cell capacity. A method of determining the optimum cathode thickness in the battery is also described. This provides a means of maximizing volumetric and gravimetric energy densities by using the optimum amount of cathode material. Batteries fabricated by using optimal materials can be operated under pulsed and dc discharge conditions over a temperature range between about -40 and +80° C.

More »»

2000

Patent

Dr. Madhav Datta, Edelstein, D. Charles, and Uzoh, C. Emeka, “Apparatus and method for the electrochemical etching of a wafer”, U.S. Patent US 08/968,1902000.[Abstract]


An electrochemical etching apparatus and method increasing the rate at which material is removed from a substrate such as a metallic surface. The apparatus includes an electrolyte delivery system positioned below and centered beneath the center of the substrate (e.g., a wafer) to be etched so that the center axis of the delivery system corresponds to the center of the wafer. The electrolyte delivery system and the wafer are then rotated relative to each other as the electrolyte is discharged from the delivery system and toward the surface of the wafer. A corresponding method for electrochemically etching a surface of the wafer with an electrolyte is also provided.

More »»

1999

Patent

P. Constantin Andricacos, Dr. Madhav Datta, Horkans, W. Jean, Kang, S. Kwon, and Kwietniak, K. Thomas, “Barrier layers for electroplated SnPb eutectic solder joints”, U.S. Patent US 09/057,2051999.[Abstract]


The present invention provides a means of fabricating a reliable C4 flip-chip structure for low-temperature joining. The electrochemically fabricated C4 interconnection has a barrier layer between the electroplated tin-rich solder bump and the ball-limiting metallurgy that protects the terminal metal in the ball-limiting metallurgy from attack by the Sn in the solder. The barrier layer is electroplated through the same photoresist mask as the solder and thus does not require a separate patterning step. A thin layer of electroplated nickel serves as a reliable barrier layer between a copper-based ball-limiting metallurgy and a tin-lead (Sn--Pb) eutectic C4 ball.

More »»

1999

Patent

W. E. Corbin Jr, Dr. Madhav Datta, Dinan, T. E., and Kern, F. W., “Electrochemical etching apparatus and method for spirally etching a workpiece”, U.S. Patent US 08/885,6081999.[Abstract]


Disclosed is an electrochemical etching apparatus including a fixture for holding a workpiece; a nozzle, positioned opposite the fixture and facing the workpiece, for impinging an etchant onto the workpiece; and an electrode for applying a voltage between the electrode and the workpiece; wherein, in operation, one of the fixture and nozzle are rotated and the nozzle is moved radially outwardly so that the workpiece is spirally etched. Also disclosed is a method of spirally etching a workpiece.

More »»

1999

Patent

J. M. Cotte, Dr. Madhav Datta, and Shenoy, R., “Lithium polymer electrolyte battery for sub-ambient temperature applications”, U.S. Patent US 08/879,4361999.[Abstract]


A primary lithium battery particularly adapted for use in self-contained self-powered devices (SSPD) for mobile communication and computing products, such as radio frequency identification tags, PCMCIA cards, and smart cards. The battery has a flexible and compact design, and utilizes a solid polymer electrolyte membrane that preferably has a polyacrylonitrile matrix. Performance of the electrolyte membrane is optimized by controlling the amount of aprotic organic solvents within the membrane within a prescribed range of ratios. In so doing, the performance characteristics of the battery closely approximate that of conventional liquid electrolytes without the safety hazards associated with the risk of liquid electrolyte leakage, and exhibit enhanced performance at sub-ambient temperatures. A further feature is that the battery's cathode is encapsulated within a polymeric matrix that eliminates the exposure hazard posed by lithium intercalation compounds used within the cathode.

More »»

1999

Patent

J. M. Cotte and Dr. Madhav Datta, “High energy density, flexible lithium primary batteries”, U.S. Patent US 08/876,7861999.[Abstract]


A primary lithium battery particularly adapted for use in self-contained self-powered devices (SSPD) for mobile communication and computing products, such as radio frequency identification tags, PCMCIA cards, and smart cards. The battery has a flexible and compact design which eliminates use of a separate electrolyte membrane by utilizing an electrolyte-bearing composite cathode that preferably has a polyacrylonitrile matrix. Performance of the battery is optimized by controlling the amount of aprotic organic solvents within the composite cathode within a prescribed range of ratios. In so doing, the performance characteristics of the battery closely approximate those having conventional liquid electrolytes without the safety concerns associated with liquid electrolyte leakage, and exhibit enhanced performance at sub-ambient temperatures. A further feature is that the composite cathode is encapsulated within a polymeric matrix that eliminates the exposure hazard posed by the lithium intercalation compounds used within the cathode. The battery is enclosed in a customized laminate stack for sealing and encapsulation. Alternative packaging embodiments are also disclosed.

More »»

1998

Patent

Dr. Madhav Datta, Kanarsky, T. Safron, Mathad, G. Swami, and Shenoy, R. V., “Etching of Ti-W for C4 rework”, U.S. Patent US 08/740,5691998.[Abstract]


A chemical etchant for the removal of titanium-tungsten containing structures from the semiconductors and a method for removing the titanium-tungsten. The etchant comprising a solution of hydrogen peroxide, a salt of EDTA, and an acid, the acid capable of preventing the deposition of tin oxide. The method of removal comprises first obtaining a wafer containing titanium-tungsten. Second, immersing the wafer having titanium-tungsten thereon for a predetermined period of time in an etchant bath comprising a solution of hydrogen peroxide, a salt of EDTA and an acid, the acid capable of preventing the deposition of tin oxide. Third, removing the treated wafer and rinsing the treated wafer and lastly, drying the wafer.

More »»

1998

Patent

Dr. Madhav Datta, Kanarsky, T. Safron, Pike, M. Barry, and Shenoy, R. Vaman, “Metallic interconnect pad, and integrated circuit structure using same, with reduced undercut”, U.S. Patent US 08/711,4331998.[Abstract]


Reduced undercutting of a titanium-tungsten layer in a ball limiting metallurgy (BLM) is achieved in the preparation of solder ball interconnect structures by removing metal oxide film which forms on the titanium-tungsten layer and etching the titanium-tungsten layer in different steps. Removing the metal oxide with an acid solution prior to etching the titanium-tungsten layer provides for a more uniform etch of the titanium-tungsten layer.

More »»

1998

Patent

J. Michael Cotte, Dr. Madhav Datta, Dinan, T. Edward, and Shenoy, R. Vaman, “Selective chemical etching in microelectronics fabrication”, U.S. Patent US5800726 A1998.[Abstract]


The present invention relates to a chemical etchant for etching metals in the presence of one or more metals not to be etched, the etchant comprising 10-25 gms EDTA, 15-35 gms K2 HPO4 and 25-45 gms oxalic acid in a liter of 30% H2 O2. More particularly, in the fabrication of interconnections for microchip structures, the present invention addresses the removal of intermediate adherent layers, e.g., Ti--W, without damaging other microchip structures made of other metals, such as Al or Al--Cu test pads; Cu and phased Cr--Cu layers; and Sn--Pb solder bumps. The use of potassium phosphate in the hydrogen peroxide+EDTA bath has been found to significantly reduce the attack on the metal not to be etched. Furthermore, the use of oxalic acid in the bath prevented the deposition of tin oxide on the substrate adherent layer metal, thus facilitating its complete removal.

More »»

1997

Patent

D. J. Brophy, Dr. Madhav Datta, Harris, D. B., Ryan, F. S., and Spera, F. A., “Tool and method for electroetching”, U.S. Patent US 08/608,8911997.[Abstract]


An electroetching tool using scanned localized application of flowing electrolyte against a workpiece such as a large area mask having high density features for the fabrication of microelectronic components. A masked molybdenum plate is suspended in a vertical direction within a tank which functions as a reservoir for a recirculating electrobyte. The electrolyte in the reservoir is filtered and pumped to a pair of travelling cathode assemblies from which the flowing electrolyte is simultaneously applied through respective charged orifices to both sides of the workpiece. The workpiece is masked on its opposite sides with mirror imaged mask apertures having corresponding opposite-sided features in registration with each other.
Each orifice through which the electrolyte is applied comprises an open groove in the surface of a block of polyvinal chloride material which groove extends in a vertical direction relative to the tank. The bottom of the groove is adjacent to a conductive plate. The open top of the groove is held closely against the masked plate as the cathode assembly is moved along the guide rails. The fresh electrobyte is introduced to the groove at the upper end thereof while the used electrolyte exits from the groove at the lower end thereof and into the tank reservoir for recirculation.

More »»

1997

Patent

Dr. Madhav Datta, Kanarsky, T. S., Pike, M. B., and Shenoy, R. V., “Method to improve uniformity and reduce excess undercuts during chemical etching in the manufacture of solder pads”, U.S. Patent US 08/659,4591997.[Abstract]


Reduced undercutting of a titanium-tungsten layer in a ball limiting metallurgy (BLM) is achieved in the preparation of solder ball interconnect structures by removing metal oxide film which forms on the titanium-tungsten layer and etching the titanium-tungsten layer in different steps. Removing the metal oxide with an acid solution prior to etching the titanium-tungsten layer provides for a more uniform etch of the titanium-tungsten layer.

More »»

1996

Patent

Dr. Madhav Datta and Shenoy, R., “Electroetching process for seed layer removal in electrochemical fabrication of wafers”, U.S. Patent US 08/346,9961996.[Abstract]


A tool and process for electroetching metal films or layers on a substrate employs a linear electrode and a linear jet of electrolyte squirted from the electrode. The electrode is slowly scanned over the film by a drive mechanism. The current is preferably intermittent. In one embodiment a single wafer surface (substrate) is inverted and the jet is scanned underneath. In another embodiment wafers are held vertically on opposite sides of a holder and two linear electrodes, oriented horizontally and on opposite sides of the holder, are scanned vertically upward at a rate such that the metal layers are completely removed in one pass. The process is especially adapted for fabricating C4 solder balls with triple seed layers of Ti-W (titanium-tungsten alloy) on a substrate, phased Cr-Cu consisting of 50% chromium (Cr) and 50% copper (Cu), and substantially pure Cu. Solder alloys are through-mask electrodeposited on the Cu layer. The seed layers conduct the plating current. During etching the seed layers are removed between the solder bumps to isolate them. The phased Cr-Cu and Cu layers are removed by a single electroetching operation in aqueous potassium sulfate and glycerol with cell voltage set to dissolve the phased layer more quickly than the Cu, avoiding excessive solder bump undercutting in the copper layer. The cell voltage may be such that the solder bump is only slightly undercut so as to form a stepped base C4 structure upon reflowing. Ti-W is removed by a chemical process.

More »»

1996

Patent

D. J. Brophy, Dr. Madhav Datta, Harris, D. B., Ryan, F. S., and Spera, F. A., “Electroetching tool using localized application of channelized flow of electrolyte”, U.S. Patent US 08/261,1701996.[Abstract]


An electroetching tool using scanned localized application of flowing electrolyte against a workpiece such as a large area mask having high density features for the fabrication of microelectronic components. A masked molybdenum plate is suspended in a vertical direction within a tank which functions as a reservoir for a recirculating electrobyte. The electrolyte in the reservoir is filtered and pumped to a pair of travelling cathode assemblies from which the flowing electrolyte is simultaneously applied through respective charged orifices to both sides of the workpiece. The workpiece is masked on its opposite sides with mirror imaged mask apertures having corresponding opposite-sided features in registration with each other.
Each orifice through which the electrolyte is applied comprises an open groove in the surface of a block of polyvinal chloride material which groove extends in a vertical direction relative to the tank. The bottom of the groove is adjacent to a conductive plate. The open top of the groove is held closely against the masked plate as the cathode assembly is moved along the guide rails. The fresh electrobyte is introduced to the groove at the upper end thereof while the used electrolyte exits from the groove at the lower end thereof and into the tank reservoir for recirculation.

More »»

1996

Patent

T. E. Dinan, Berridge, K. G., Dr. Madhav Datta, Kanarsky, T. S., Pike, M. B., and Shenoy, R. V., “Vertical electroetch tool nozzle and method”, U.S. Patent US 08/460,4391996.[Abstract]


A nozzle is provided for use in electroetching a vertically oriented workpiece, comprising a housing having a top, sides, and bottom for creating a flow of etching solution on the workpiece, and means for shaping the flow of etching solution into a moving channel to improve etch uniformity of the workpiece.

More »»

1996

Patent

Dr. Madhav Datta and Shenoy, R. V., “Electroetching method and apparatus”, U.S. Patent US 08/459,7601996.[Abstract]


A tool and process for electroetching metal films or layers on a substrate employs a linear electrode and a linear jet of electrolyte squirted from the electrode. The electrode is slowly scanned over the film by a drive mechanism. The current is preferably intermittent. In one embodiment a single wafer surface (substrate) is inverted and the jet is scanned underneath. In another embodiment wafers are held vertically on opposite sides of a holder and two linear electrodes, oriented horizontally and on opposite sides of the holder, are scanned vertically upward at a rate such that the metal layers are completely removed in one pass. The process is especially adapted for fabricating C4 solder balls with triple seed layers of Ti--W (titanium-tungsten alloy) on a substrate, phased Cr--Cu consisting of 50% chromium (Cr) and 50% copper (Cu), and substantially pure Cu. Solder alloys are through-mask electrodeposited on the Cu layer. The seed layers conduct the plating current. During etching the seed layers are removed between the solder bumps to isolate them. The phased Cr--Cu and Cu layers are removed by a single electroetching operation in aqueous potassium sulfate and glycerol with cell voltage set to dissolve the phased layer more quickly than the Cu, avoiding excessive solder bump undercutting in the copper layer. The cell voltage may be such that the solder bump is only slightly undercut so as to form a stepped base C4 structure upon reflowing. Ti--W is removed by a chemical process.

More »»

1996

Patent

Dr. Madhav Datta and Shenoy, R. V., “Method for making a thin flexible primary battery for microelectronics applications”, U.S. Patent US 08/329,3471996.[Abstract]


A method is provided for making a flexible primary battery suitable for microelectronics applications, and more particularly, for use with self-contained self-powered portable devices (SSPD) such as RF-ID tags. The method generally employs photolithography and etching techniques to minimize the thicknesses of metal foils required in the structure of the battery, as well as packaging methods which yield a flexible and durable battery having a thickness of not more than about 0.5 millimeter, and preferably about 0.3 millimeter or less, and a relatively small size on the order of a few square centimeters in surface area.

More »»

1996

Patent

Dr. Madhav Datta and O'Toole, T. R., “Electrochemical metal removal technique for planarization of surfaces”, U.S. Patent US 08/300,6231996.[Abstract]


A high speed electrochemical metal removal technique provides for planarization of multilayer copper interconnection in thin film modules. The process uses a neutral salt solution, is compatible with the plating process and has minimum safety and waste disposal problems. The process offers tremendous cost advantages over previously employed micromilling techniques for planarization.

More »»

1996

Patent

Dr. Madhav Datta, Romankiw, L. T., and Shenoy, R. V., “Elimination of island formation and contact resistance problems during electroetching of blanket or patterned thin metallic layers on insulating substrate”, U.S. Patent US 08/367,5501996.[Abstract]


In through-mask electroetching of a metal film on top of an insulating substrate, the shape of the metal film being etched is a function of the mask opening, the spacing between the openings and the thickness of the mask. An analysis of the electric field around the mask and the metal film is used to determine conditions leading to the formation of islands of unetched metal films within the openings. The analysis is then used to design the mask pattern and eliminate these islands. The increase in the ratio of the mask thickness to the opening width for eliminating the islands also lowers the undercutting of the mask. Premature stoppage of the electroetching process arising from the isolation of the sample film from the contact is also addressed. The electrical contact to the sample is made at one end and a nozzle jet of electrolyte is slowly swept from the far end of the sample towards the electrical contact. The nozzle speed is matched with the metal removal rate and the electrical contact is exposed to the electrolyte at the end of the process.

More »»

1995

Patent

S. G. Barbee, Dr. Madhav Datta, Heinz, T. F., Li, L., Ratzlaff, E. H., and Shenoy, R. V., “Method and apparatus for contactless real-time in-situ monitoring of a chemical etching process”, U.S. Patent US 08/269,8651995.[Abstract]


A contactless method and apparatus for in-situ chemical etch monitoring of an etching process during etching of a workpiece with a wet chemical etchant are disclosed. The method comprises steps of providing a base member having a reference surface; releasably securing the workpiece to the base member; providing at least two sensors disposed on the base member to be proximate to but not in contact with the outer perimeter of the workpiece surface; and monitoring an electrical characteristic between said at least two sensors, wherein a prescribed change in the electrical characteristic is indicative of a prescribed condition of the etching process.

More »»

1995

Patent

S. G. Barbee, Dr. Madhav Datta, Heinz, T. F., Li, L., Ratzlaff, E. H., and Shenoy, R. V., “Method and apparatus for contactless realtime in-situ monitoring of a chemical etching process”, U.S. Patent US 08/414,4041995.[Abstract]


A contactless method and apparatus for in-situ chemical etch monitoring of an etching process during etching of a workpiece with a wet chemical etchant are disclosed. The method comprises steps of providing a base member having a reference surface; releasably securing the workpiece to the base member; providing at least two sensors disposed on the base member to be proximate to but not in contact with the outer perimeter of the workpiece surface; and monitoring an electrical characteristic between said at least two sensors, wherein a prescribed change in the electrical characteristic is indicative of a prescribed condition of the etching process.

More »»

1995

Patent

Dr. Madhav Datta and Shenoy, R. V., “Selective etching of TiW for C4 fabrication”, U.S. Patent US 08/260,0491995.[Abstract]


A chemical etchant (and a method for forming the etchant) is disclosed for removing thin films of titanium-tungsten alloy in microelectronic chip fabrication. The alloy removed is preferably 10% Ti and 90% W, which is layered onto a substrate under chromium and copper seed layers for electrodeposition of C4 solder bumps. In this application the Ti--W etchant should not attack aluminum, chromium, copper, or lead-tin solders, and should dissolve Ti--W rapidly. The invention achieves this with a mixture of 30% by weight hydrogen peroxide and water, to which is added EDTA and potassium sulfate. The hydrogen peroxide etches Ti--W rapidly at temperatures between 40° C. and 60° C. EDTA forms a complex with tungsten to prevent plating of the Pb--Sn solder with W, and potassium sulfate forms a protective coating on the Pb--Sn solder to protect it from chemical attack.

More »»

1995

Patent

D. J. Brophy, Dr. Madhav Datta, Harris, D. B., Kurdziel, M. T., and Ryan, F. S., “Fabrication of moly masks by electroetching”, U.S. Patent US 08/285,3711995.[Abstract]


Masks for microelectronics technology are fabricated by electrochemical etching. Molybdenum sheet or foil is masked with patterned photoresist on one side, and a mating, mirror-image pattern of photoresist is applied on the other side of the foil in exact registration with the first pattern. The foil is immersed in electrolyte (an aqueous solution of sodium nitrate, sodium hydroxide, thiourea, and surfactant) along with nickel anode plates held parallel to the foil surfaces 1-3 cm away. The anode plate is made slightly smaller than the mask area of the foil. When voltage is applied across the cell, the foil is etched through to form vias. The electrolyte is pumped across the surface of the foil and uniform flow velocity over the foil surface is achieved.

More »»

1994

Patent

Dr. Madhav Datta and Romankiw, L. T., “Electrochemical micromachining tool and process for through-mask patterning of thin metallic films supported by non-conducting or poorly conducting surfaces”, U.S. Patent US 07/819,3101994.[Abstract]


The present invention describes a high speed, high precision electrochemical micromachining tool, chemical solution and method for the one sided through-mask micropatterning of conducting foils and films supported by insulating material. The tool of the present invention can include either a movable plate means allowing for the movement of the workpiece to and fro above the cathode assembly, or a movable cathode assembly means allowing for the movement of said cathode assembly to and fro beneath the workpiece. Said cathode assembly also consists of a nozzle assembly from which the electrolytic solution emerges as electrolytic shower and impinges upon the workpiece. Methods to resolve the problems related to the loss of electrical contact during the electrochemical micromachining process are also described.

More »»

1993

Patent

Dr. Madhav Datta, King, D. E., Knight, A. D., and Sambucetti, C. J., “High performance metal cone contact”, U.S. Patent US 07/797,5751993.[Abstract]


An electrical interconnection, which includes a method for fabricating the device, is disclosed. The interconnection comprises two contact surfaces, on at least one of which is disposed at least one solid metal conical projection in predetermined dimension and location. Rather than necessarily being permanently cojoined, the contact surfaces are attachable and detachable when desired. The conical projections on one contact surface make ohmic contact, either by wiping with an intermeshing like structure on a second contact surface or by contacting a second contact surface which is a substantially flat contact pad. An interconnection, in this invention, is the combination of at least one contact having individual conical projections and another contact, optionally having individual conical projections. The conical projections are formed in metal by electrochemical machining in neutral salt solution, optionally in a continuous foil. The conical projections are also optionally formed on the head of a contact pin.

More »»

1993

Patent

Dr. Madhav Datta and Romankiw, L. T., “Electrochemical tool for uniform metal removal during electropolishing”, U.S. Patent US 07/819,2981993.[Abstract]


The present invention relates to an electropolishing tool for the removal of metal from a workpiece, said electropolishing tool comprising a container means for retaining an electrolytic solution, a cathode assembly in the shape of a pyramid the height of which is adjustable, a power supply means including a negative terminal and a positive terminal with said negative terminal being electrically connectable to said cathode assembly, a plate means for holding the workpiece and for forming an electrical connection to the workpiece, said plate means connected to the positive terminal of said power supply means, and an enclosure means placed over the workpiece leaving only the surface of the workpiece which is to be polished exposed to the electrolytic solution such that when the workpiece is secured to said plate means and said cathode assembly is connected to the negative terminal of said power supply means and is placed over the said enclosure means directly facing the workpiece enclosed therein, that portion of the workpiece exposed to the electrolytic solution undergoes electropolishing.

More »»

1993

Patent

B. N. Agarwala, Dr. Madhav Datta, Gegenwarth, R. E., Jahnes, C. V., Miller, P. M., III, H. A. Nye, Roeder, J. F., and Russak, M. A., “Etching processes for avoiding edge stress in semiconductor chip solder bumps”, U.S. Patent US 07/938,0741993.[Abstract]


Etching processes are disclosed for producing a graded or stepped edge profile in a contact pad formed between a chip passivating layer and a solder bump. The stepped edge profile reduces edge stress that tends to cause cracking in the underlying passivating layer. The pad comprises a bottom layer of chromium, a top layer of copper and an intermediate layer of phased chromium-copper. An intermetallic layer of CuSn forms if and when the solder is reflowed, in accordance with certain disclosed variations of the process. In all the variations, the solder is used as an etching mask in combination with several different etching techniques including electroetching, wet etching, anisotropic dry etching and ion beam etching.

More »»

1992

Patent

Dr. Madhav Datta, King, D. E., Knight, A. D., and Sambucetti, C. J., “Method for making a detachable electrical contact”, U.S. Patent US 07/596,4321992.[Abstract]


An electrical interconnection, which includes a method for fabricating the device, is disclosed. The interconnection comprises two contact surfaces, on at least one of which is disposed at least one solid metal conical projection in predetermined dimension and location. Rather than necessarily being permanently cojoined, the contact surfaces are attachable and detachable when desired. The conical projections on one contact surface make ohmic contact, either by wiping with an intermeshing like structure on a second contact surface or by contacting a second contact surface which is a substantially flat contact pad. An interconnection, in this invention, is the combination of at least one contact having individual conical projections and another contact, optionally having individual conical projections. The conical projections are formed in metal by electrochemical machining in neutral salt solution, optionally in a continuous foil. The conical projections are also optionally formed on the head of a contact pin.

More »»

1992

Patent

Dr. Madhav Datta and Rocheleau, K. U., “Method for electrochemical cleaning of metal residue on molybdenum masks”, U.S. Patent US 07/806,9931992.[Abstract]


An electrochemical method for selective removal of the metallic residual stain which forms on molybdenum masks during processing of integrated circuits. The method forms an electrolytic cell which has, as its elements, the mask as the anode, an electrolyte of phosphoric acid and glycerol, a cathode, and a power supply. That cell is used to electrochemically clean the mask, forming a surface film and electrolyte layer on the mask which includes the metallic residual stain. To remove the surface film and electrolyte layer and, concurrently, the metallic residual stain, the mask is rinsed with water. It is then dried.

More »»

1991

Patent

J. C. Andreshak, Dr. Madhav Datta, Romankiw, L. T., and Vega, L. F., “Apparatus, electrochemical process, and electrolyte for microfinishing stainless steel print bands”, U.S. Patent US 07/578,9711991.[Abstract]


An apparatus is provided for electrochemically processing an anodic material in strip form, such as the stainless steel print bands used in high speed printers. Also provided is an electrochemical process including electroetching, electropolishing, or both to obtain microfinishing of the material. Moreover, an electrolyte is provided which is a mixture of phosphoric acid, sulfuric acid, and glycerol in which the material removal rate is controlled by the addition of small amounts of sodium chloride. The electrochemical process operates at ambient temperature over a wide range of current density.

More »»

Publication Type: Book

Year of Publication Publication Type Title

2010

Book

T. Osaka, Dr. Madhav Datta, and Shacham-Diamand, Y., Electrochemical Nanotechnologies, vol. 1. New York: Springer , 2010, p. 279.[Abstract]


In this book, the term "electrochemical nanotechnology" is defined as nanoprocessing by means of electrochemical techniques. This introductory book reviews the application of electrochemical nanotechnologies with the aim of understanding their wider applicability in evolving nanoindustries. These advances have impacted microelectronics, sensors, materials science, and corrosion science, generating new fields of research that promote interaction between biology, medicine, and microelectronics.

This volume reviews nanotechnology applications in selected high technology areas with particular emphasis on advances in such areas. Chapters are classified under four different headings: Nanotechnology for energy devices - Nanotechnology for magnetic storage devices - Nanotechnology for bio-chip applications - Nanotechnology for MEMS/Packaging.

More »»

2009

Book

Y. Shacham-Diamand, Osaka, T., Ohba, T., and Dr. Madhav Datta, Advanced Nanoscale ULSI Interconnects: Fundamentals and Applications. New York: Springer, 2009, p. XX, 552.[Abstract]


Advanced Nanoscale ULSI Interconnects: Fundamental and Applications brings a comprehensive description of copper based interconnect technology for Ultra Large Scale Integration (ULSI) technology to Integrated Circuit (ICs) application. This book reviews the basic technologies used today for the copper metallization of ULSI applications: deposition and planarization. It describes the materials used, their properties, and the way they are all integrated, specifically in regard to the copper integration processes and electrochemical processes in the nanoscale regime. The book also presents various novel nanoscale technologies that will link modern nanoscale electronics to future nanoscale based systems. This diverse, multidisciplinary volume will appeal to process engineers in the microelectronics industry; universities with programs in ULSI design, microelectronics, MEMS and nanoelectronics; and professionals in the electrochemical industry working with materials, plating and tool vendors.

More »»

2004

Book

Dr. Madhav Datta, Osaka, T., and J Schultze, W., Microelectronic packaging, 1st ed., vol. 3, 3 vol. CRC press, 2004, p. 564.[Abstract]


Microelectronic Packaging analyzes the massive impact of electrochemical technologies on various levels of microelectronic packaging. Traditionally, interconnections within a chip were considered outside the realm of packaging technologies, but this book emphasizes the importance of chip wiring as a key aspect of microelectronic packaging, and focuses on electrochemical processing as an enabler of advanced chip metallization.

Divided into five parts, the book begins by outlining the basics of electrochemical processing, defining the microelectronic packaging hierarchy, and emphasizing the impact of electrochemical technology on packaging. The second part discusses chip metallization topics including the development of robust barrier layers and alternative metallization materials. Part III explores key aspects of chip-package interconnect technologies, followed by Part IV's analysis of packages, boards, and connectors which covers materials development, technology trends in ceramic packages and multi-chip modules, and electroplated contact materials. Illustrating the importance of processing tools in enabling technology development, the book concludes with chapters on chemical mechanical planarization, electroplating, and wet etching/cleaning tools.

Experts from industry, universities, and national laboratories submitted reviews on each of these subjects, capturing the technological advances made in each area. A detailed examination of how packaging responds to the challenges of Moore's law, this book serves as a timely and valuable reference for microelectronic packaging and processing professionals and other industrial technologists.

More »»

2002

Book

W. J Schultze, Osaka, T., and Dr. Madhav Datta, Electrochemical microsystem technologies , 1st ed., vol. 2, 3 vol. Taylor & Francis, 2002, p. 592.[Abstract]


Driven by the electronics industry, electrochemical technology has rapidly evolved, finding increasing applications in microelectronics, batteries, sensors, materials science, industrial fabrication, corrosion, microbiology, neurobiology and medicine. Electrochemical Microsystem Technologies provides an overview of the technological status; the development of micropatternings and micro-biosensors; and the applications of micropower with electrochemical microsystems.

This book covers a wide spectrum of issues ranging from fundamental electrochemical processes to their applications in micro- and nanofabrication, microanalyses, microsensing, and their interaction with inorganic surfaces and biological systems. The editors provide comprehensive background to unique processes, such as the technological development of miniaturization, microfabrication, thin film deposition, etching, cleaning, planarization, and silicon processing technologies to introduce a wide range of applications in context.

More than 40 internationally recognized industry, research, and medical experts provide insight on the current status and future trends in their fields. They also highlight the impact of applying electrochemical microsystem technologies on industries such as storage and packaging; microelectronics, sensors, and portable electronics; machining, polishing, anodization, and plating technologies in heavy industries; biosensing, biological implant technology, and neurobiology; and cross-disciplinary integrated systems.

Electrochemical Microsystem Technologies is a valuable reference for graduate/postgraduate students, technologists, and researchers working in the field of electrochemical technology.

More »»

2000

Book

T. Osaka and Dr. Madhav Datta, Energy storage systems in electronics, 3 vol. CRC Press, 2000, p. 604.[Abstract]


This volume illustrates the technological advances made in recent years in the development of battery and other energy storage systems. Discussions of present and near future battery technologies are included as well as emerging energy technologies that have the potential to impact on the portable electronics industry in the long term. This text provides a complete overview of the technology status and trends, with a focus on scientific developments, particularly in materials, that have led to technological breakthroughs.

More »»

1998

Book

M. Paunovic, Dr. Madhav Datta, Matlosc, M., Osaka, T., and Talbot, J. B., Fundamental aspects of electrochemical deposition and dissolution including modeling, vol. 97-27. Pennington, New Jersey: The Electrochemical Society, 1998, p. 646.

1998

Book

Dr. Madhav Datta, Special issue of IBM Journal of Research and Development devoted to Electrochemical Microfabrication (Guest Editor), vol. 42. Riverton, NJ, USA: IBM Corp. , 1998.

1997

Book

Dr. Madhav Datta, Fenton, J. M., and Brooman, E. W., Environmental Aspects of Electrochemical Technology: Applications in Electronics, vol. 96-21. Pennington, New Jersey: The Electrochemical Society, 1997, p. 296.

1995

Book

Dr. Madhav Datta, MacDougall, B. R., and Fenton, J. M., High Rate Metal Dissolution Processes, vol. 95-19. Pennington, New Jersey: The Electrochemical Society, 1995.

1994

Book

K. Sheppard, Dr. Madhav Datta, and Dukovic, J. O., Electrochemical Microfabrication II, vol. 94-3. Pennington, New Jersey: The Electrochemical Society , 1994.

1994

Book

Dr. Madhav Datta, Special Issue of Processing of Advanced Materials devoted to Environmental Aspects (Guest Editor), vol. 4, 4 vol. Chapman and Hall, 1994.

1993

Book

L. T. Romankiw, Osaka, T., Yamazaki, Y., and Dr. Madhav Datta, Electrochemical Technology Applications in Electronics, vol. 93-20. Pennington, New Jersey: The Electrochemical Society , 1993.

1992

Book

Dr. Madhav Datta, Sheppard, K., and Snyder, D., Electrochemical Microfabrication-I, vol. 92-3. Pennington, New Jersey : The Electrochemical Society , 1992.

Publication Type: Book Chapter

Year of Publication Publication Type Title

2010

Book Chapter

Dr. Madhav Datta, “Microelectronic Packaging Trends and the Role of Nanotechnology”, in Electrochemical Nanotechnologies, New York: Springer, 2010, pp. 227–253.[Abstract]


The microelectronic packaging industry is undergoing major changes to keep pace with the ever-increasing demands imposed by high performing chips and by end-use system applications. Solutions using advanced materials for microprocessor interconnect scaling and chip package interconnects, novel concepts in heat management systems, and improvements in package substrates continue to drive major packaging efforts. Advances in electrochemical technologies have played an important role in the evolution of such solutions for miniaturization of microelectronic devices and packages. Indeed, since the development of through-mask plating for thin film heads in the1960s and 1970s, an enormous amount of industrial and academic R&D effort has positioned electrochemical processing among the most sophisticated processing technologies employed in the microelectronics industry today [1–4]. Electrochemical processing is perhaps better understood than some of the dry processing technologies used in the microelectronics industry. Compared to other competing dry processing technologies, it has emerged as a more environmentally-friendly and cost-effective fabrication method. Electrochemical processing has, thus, become an integral part of advanced wafer processing fabs and an enabling technology for nanofabrication [5]. As the electronics industry faces the challenges of extending Moore’s law, electrochemical processing is expected to continue to enable further miniaturization of high-performance chip interconnects, packages, and printed circuit boards. Evolving novel approaches to electrochemical processing using nano-materials and nano-fabrication techniques have started to make tremendous impact on further miniaturization of high performance devices and packages. A detailed discussion of different facets of technology advances in electronic packaging is difficult to present in the limited space of this chapter. The current chapter, therefore, makes an effort to capture some of the key developments in microelectronic packaging while highlighting the impact of electrochemical processing. Also included is a brief discussion of some of the foreseeable applications of nano-materials and nano-structures in advanced packaging.

More »»

2009

Book Chapter

Dr. Madhav Datta, “Electrodeposition”, in Advanced Nanoscale ULSI Interconnects: Fundamentals and Applications, Shacham-Diamand, Y., Osaka, T., Datta, M., Ohba, T., editors, Springer, 2009, pp. 63–71.[Abstract]


Electrodeposition is the process of cathodic deposition of metals, alloys, and other conducting materials from an electrolyte using an external potential (electric current) for the cation reduction process to occur at the working substrate. The deposition process is also known as electrolytic plating, electroplating, or simply plating. Electrodeposition is widely employed in a variety of applications ranging from coatings for wear and corrosion resistance to nanoscale feature fabrication for ultra-large-scale integration (ULSI). The deposition thickness may vary from few angstroms of uniformly deposited compact films to electroformed structures that are millimeters thick. Compared to competing vacuum deposition processes, electrodeposition has emerged as more environmentally friendly and cost-effective micro/nanofabrication method.

More »»

2009

Book Chapter

Dr. Madhav Datta, “Electrochemical processing tools for advanced copper interconnects: an introduction”, in Advanced Nanoscale ULSI Interconnects: Fundamentals and Applications, Shacham-Diamand, Y., Osaka, T., Datta, M., Ohba, T., editors, Springer, 2009, pp. 389–396.[Abstract]


The change from vacuum-deposited aluminum to electroplated copper in 1997 brought about a paradigm shift in interconnect technology and in chip making [1]. Since then, most of the leading chip manufacturers have converted to electroplated Cu technology for chip interconnects. Cu interconnects are fabricated by dual Damascene process which is referred to a metallization patterning process by which two insulator (dielectric) levels are patterned, filled with copper, and planarized to create a metal layer consisting of vias and lines. The process steps consist of laying a sandwich of two levels of insulator and etch stop layers that are patterned as holes for vias and troughs for lines. They are then filled with a single metallization step. Finally, the excess material is removed, and the wafer is planarized by chemical mechanical polishing (CMP). While finer details of exact sequence of fabrication steps vary, the end result of forming a metal layer remains the same in which vias are formed in the lower layer, and trenches are formed in the upper layer. Electroplating enables deposition of Cu in via holes and overlying trenches in a single step thus eliminating a via/line interface and significantly reducing the cycle time. Due to these reasons and due to relatively less expensive tooling, electroplating is a cost-effective and efficient process for Cu interconnects [2, 3]. Compared with vacuum deposition processes, electroplated Cu provides improved super filling capabilities and abnormal grain growth phenomena. These properties contribute significantly to improved reliability of Cu interconnects. With the proper choice of additives and plating conditions, void-free, seam-free Damascene deposits are obtained which eliminates surface-like fast diffusion paths for Cu electromigration.

More »»

2005

Book Chapter

Dr. Madhav Datta, “Electrochemical processing technologies and their impact in microelectronic packaging”, in Microelectronic Packaging Edited by J . W . Schultze , T . Osaka , and M . Datta, US: CRC Press, 2005, pp. 3-27.

2005

Book Chapter

Dr. Madhav Datta, “ Flip-chip interconnection”, in Microelectronic Packaging Edited by J . W . Schultze , T . Osaka , and M . Datta, CRC Press, 2005, pp. 167-200.

2005

Book Chapter

V. Dubin, Simka, H. S., Shankar, S., Moon, P., Marieb, T., and Dr. Madhav Datta, “Electroplating process for cu chip metallization”, in Microelectronic Packaging, Datta, M., Osaka, T., Schultze, J.W., editors, Boca Raton: US: CRC Press, 2005, p. 31.

1996

Book Chapter

Dr. Madhav Datta, “Electrochemical Micromachining”, in Electrochemical Technology Innovations and New Developments, Editors Masuko, N., Osaka, T., Ito, Y., editors, Kodansha, G&B Publishers, 1996, pp. 137-158.

1983

Book Chapter

Dr. Madhav Datta and Landolt, D., “Recent Investigations of Electrochemical Metal Shaping”, in DECHEMA Monographien, vol. 93, 1983, p. 131.

1983

Book Chapter

Dr. Madhav Datta, Mathieu, H. J., and Landolt, D., “Application of angle resolved XPS and AES depth profiling to the study of transpassive films on nickel”, in Passivity of metals and semiconductors, Amsterdam (Netherlands): Elsevier, 1983, pp. 113-118.[Abstract]


Variation of the take-off angle in XPS permits one to obtain information on chemical composition of very thin films as a function of depth without the use of ion sputtering. The method together with Auger depth profiling was applied to the study of nickel surfaces subjected to transpassive dissolution in nitrate solution. Obtained results indicate the presence of thin oxide films containing nitrogen which is present in a reduced form.

More »»

Publication Type: Magazine Article

Year of Publication Publication Type Title

2008

Magazine Article

Dr. Madhav Datta, “Liquid cooling targets advanced microelectronics”, Electronic Products, p. 29, 2008.

2007

Magazine Article

Dr. Madhav Datta, “Precision Liquid Cooling Meets Thermal Challenge of Newest Microelectronic Packaging Trends”, Thermal News, Volume 1, issue 1, pp 1-11, Fall 2007., vol. 1, no. 1, pp. 1-11, 2007.

1995

Magazine Article

Dr. Madhav Datta, “Energy Storage Systems, National Electronics Manufacturing Technology Roadmaps”, National Electronics Manufacturing Initiative, pp. 117-137, 1995.

1983

Magazine Article

Dr. Madhav Datta, “Le Polissage Electrochimique”, La Revue Polytechnique (in French), vol. 1435, no. 2, p. 166, 1983.

Publication Type: Conference Proceedings

Year of Publication Publication Type Title

2006

Conference Proceedings

Dr. Madhav Datta, “Electrochemical Processing Trends in Micro/Nano Electronics”, 8th International Symposium on Magnetic Materials, Processes, and Devices, Honolulu, Hawaii S. Krongelb, C. Bonhote, T. Osaka, Y. Kitamoto, editors, . 2006.

1999

Conference Proceedings

S. K. Kang, Horkans, J., Andricacos, P. C., Carruthers, R. A., Cotte, J., Dr. Madhav Datta, Gruber, P., Harper, J. M. E., Kwietniak, K., Sambucetti, C., Shi, L., Brouillette, G., and Danovitch, D., “Pb-free solder alloys for flip chip applications”, Proceedings of 49th Electronic Components and Technology Conference, 1999. IEEE, San Diego, CA, pp. 283 - 288, 1999.[Abstract]


In addition to the environmental issue regarding the use of Pb-bearing solders in microelectronics applications, there is another issue associated with using Pb-bearing solders in interconnections, like flip chip solder interconnections in an advanced CMOS technology, that are near active circuits. In order to minimize the soft error rate due to alpha particle emission from Pb-bearing solder alloys, Pb-free solder alloys were studied as possible replacements for the Pb-based solders that are presently used in flip chip interconnections. A large number of solder compositions was selected for evaluation. Since all the candidate alloys were Sn-based, alternatives for the ball-limiting metallurgy (BLM) were also investigated. The physical, chemical, mechanical and electrical properties of the alloys were determined by thermal analysis, wettability testing, microhardness measurement, electrical resistivity measurement, interfacial reaction study and others. Test vehicles were also built with some selected Pb-free solder alloys with the proper BLM to evaluate integrity of the flip chip solder bump structure. Based on this study, a few candidate solder alloys were selected with a proper BLM barrier layer for flip chip applications

More »»

1997

Conference Proceedings

Dr. Madhav Datta, “Hazardous Waste Reduction Through Electrochemical Micromachining”, ECS Proceedings Environmental Aspects of Electrochemical Technology: Applications in Electronics, Datta, M., Fenton, J.M., Brooman, E.W., editors, vol. 96-21. p. 276, 1997.

1997

Conference Proceedings

Dr. Madhav Datta, “Microfabrication by through-mask electrochemical micromachining”, Proceedings of SPIE, Micromachining and Microfabrication, vol. 3223. International Society for Optics and Photonics, p. 178, 1997.[Abstract]


Patterning of thin films or foils by wet etching generally involves selective material removal through photoresist masks. Compared to the commonly employed chemical etching process, the electrochemical method of metal removal offers better control and flexibility for microfabrication. Other advantages include higher machining rate, the use of non-toxic and non- corrosive electrolyte and the possibility of machining a wide range of electrically conducting materials. Electrochemical metal removal (electrochemical micromachining) is now receiving attention in the electronics and other high-tech industries as a greener processing technology for microfabrication. Several examples of the application of electrochemical micromachining are presented in this paper. These examples demonstrate the challenges and opportunities offered by electrochemical metal removal in microfabrication.

More »»

1996

Conference Proceedings

S. - J. Jaw, Fenton, J. M., and Dr. Madhav Datta, “Investigation of feature shape during jet electrochemical micromachining”, ECS Proceedings, High Rate Metal Dissolution Processes, Datta, M., MacDougall, B.R., Fenton, J.M., editors, vol. 95-19. pp. 236-247, 1996.

1996

Conference Proceedings

Dr. Madhav Datta, “Electrochemical Micromachining: An Alternative Microfabrication Technology in MEMS”, Proceedings of the Fourth International Symposium on Magnetic Materials, Processes, and Devices with Applications in Storage and Micro-Electromechanical Systems, L.T. Romankiw, D. Herman, editors, ECS Proceedings , vol. 95-18. p. 273, 1996.

1995

Conference Proceedings

T. E. Dinan and Dr. Madhav Datta, “The kinetics of copper etching in acidic ammonium persulfate solutions”, ECS Proceedings High Rate Metal Dissolution Processes, Datta, M., MacDougall, B.R., Fenton, J.M., editors, , vol. 95-19. pp. 189–201, 1995.

1994

Conference Proceedings

C. Narayan, Fenton, J., and Dr. Madhav Datta, “Environmentally conscious materials and manufacturing processes”, MRS Proceedings, vol. 344. Cambridge Univ Press, p. 203, 1994.[Abstract]


Environmental and safety issues are becoming increasingly critical for the selection of materials and their processing techniques. While the choice of “green” materials is important from the perspective of disposal of spent or used products, the choice of environmentally sound processes is important to cut down manufacturing waste and limit the use of toxic solvents and solids. Some examples from the electronics and the aerospace industry are described.

More »»

1994

Conference Proceedings

Dr. Madhav Datta, Jaw, S. - J., and Fenton, J. M., “High rate anodic dissolution and jet electrochemical micromachining of tungsten”, ECS Proceedings, Electrochemical Microfabrication II, Datta, M., Sheppard, K., Dukovic, J.O., editors, vol. 94-32. pp. 217–228, 1994.

1993

Conference Proceedings

Dr. Madhav Datta and Romankiw, L. T., “Through-Mask Electrochemical Micromachining of Thin Films”, Electrochemical Technology Applications in Electronics, Romankiw, L.T., Datta, M., Osaka, T., Yamazaki, Y., editors, ECS Proceedings, vol. 93-20. p. 123, 1993.

1992

Conference Proceedings

Dr. Madhav Datta, “Fabrication of V shaped Nozzles in Metal Foils by Through-Mask Electrochemical Micromachining”, Electrochemical MIcrofabrication-I, ECS Proceedings, Datta, M., Sheppard, K., Snyder, D., editors, vol. Volume 92-3. p. 61, 1992.

1992

Conference Proceedings

Dr. Madhav Datta, “Maskless Laser Enhanced Electrodeposition of Lead-Tin Solder”, Electrochemical Microfabrication-I, ECS Proceedings, Datta, M., Sheppard, K., Snyder, D., editors, vol. 92-3. p. 137, 1992.

1992

Conference Proceedings

Dr. Madhav Datta, “Transport Processes During High Rate Dissolution of Metals”, in Metal Deposition and Dissolution, D.T. Chin, R.E. White, J.W. Van Zee, J.W. Weidner, editors, Electrochem. Society, vol. PV-92-23. p. 221, 1992.

1992

Conference Proceedings

Dr. Madhav Datta, “Selective Material Removal by Wet Etching: Applications in Microfabrication”, Proceedings of INCOSURF-92. Bangalore, p. 230, 1992.

1990

Conference Proceedings

C. Clerc, Dr. Madhav Datta, and Romankiw, L. T., “High Speed Maskless Patterning by Electrolytic Jet, in Patterning Science and Technology”, Patterning Science and Technology, R. Gleason, G.J. Heffron, L.K. White, editors, vol. PV-90-1. Electrochemical Soc., 1990.

1990

Conference Proceedings

Dr. Madhav Datta, “Processing of Electronic Materials by Wet Etching”, Proceedings of National Electronic Packaging and Production Conference, . Anaheim, p. p93, 1990.

1989

Conference Proceedings

Dr. Madhav Datta, Vega, L. F., Romankiw, L. T., and Duby, P., “Potentiostatic and Potentiodynamic Study of Electrolpolishing of Iron”, ECS Symposium , vol. 89-1. p. 123, 1989.

1989

Conference Proceedings

Dr. Madhav Datta, “Challenges in Electrochemical Machining Related to Surface Preparation”, Proceedings of National Electronic Packaging and Production Conference, Anaheim, . Anaheim, p. 122, 1989.

1988

Conference Proceedings

Dr. Madhav Datta, “Microfabrication by Electrochemical Machining”, Intl. Microelctronics Conference. ISHM, Tokyo, p. 47, 1988.

1987

Conference Proceedings

Dr. Madhav Datta, Romankiw, L. T., Vigliotti, D. R., and Von Gutfeld, R. J., “Laser Chemical Etching of Metals in Neutral Salt Solutions”, MRS Symposium Proceedings, vol. 101. Cambridge Univ Press, p. 449, 1987.[Abstract]


We report the first results of experiments using a focused argon ion laser to locally induce chemical etching of steel and stainless steel in neutral salt solutions for maskless patterning. The solutions include sodium chloride, sodium nitrate and potassium sulfate. Vertical etch rates up to 4 microns/s are observed.

More »»

1980

Conference Proceedings

Dr. Madhav Datta, “Electrochemical Machining under Steady State and Pulsed Current Conditions”, Proceedings International Symposium for Electro-machining, CIRP. Cracow, Poland, pp. 251-258, 1980.

1980

Conference Proceedings

Dr. Madhav Datta, “Influence of Anodic Reactions on Electrochemical Machining Performance”, Proceedings Second Intl. Symposium on Industrial and Oriented Basic Electrochemistry. Madras, India, pp. 1-10, 1980.

Peer Reviewed International Journals (Under Review)

  1. Datta, M., Bonded Ceramic-Metal Layers for fabrication of Thermal Conduction Plates, submitted for publication in J. Materials Processing technollogy (under review); IF: 2.041
  2. Datta, M., Choi, H.W., Microheat Exchanger for Cooling High Power Laser Diodes, submitted for publication in J. Appld. Thermal Engineering (under Review); IF: 2.88
  3. Datta, M., Microfabrication by High rate Anodic Dissolution: Fundamentals and Applications, to be submitted in JECS; IF: 2.859

Reviewer – Journals and Conferences

  1. Electrochmica Acta, 2. J. Electrochemical Society, 3. J. Applied Electrochemistry, 4. Surface Science, 5. Corrosion Science, 6. Micro Nanosystems; 7. Numerous international conferences.

Conferences – Organized

  1. Datta, M., Symposium Organizer, Processing of Electronic Materials by Wet Etching NEPCON-West, Anaheim, CA, Feb-March 1990.
  2. Datta, M., Symposium Organizer, Electrochemical Microfabrication I, ECS Fall Meeting, Phoenix, October 1991
  3. Datta, M., Symposium Co-organizer, Electrochemical Technology Applications in Electronics, Spring Meeting, Honolulu, May 1993 (Symposium Co-Chair)
  4. Datta, M., Symposium Organizer, Electrochemical Microfabrication –II, ECS Meeting, Miami Beach, Florida, October 1994.
  5. Datta, M., Symposium Organizer, High Rate Metal Dissolution Processes, ECS Fall Meeting, Chicago, October 1995.
  6. Datta, M., Symposium Co-organizer, First International Symposium on Electrochemical Microsystem Technologies, Düsseldorf, August 1996.
  7. Datta, M., Symposium Organizer, Environmental Aspects of Electrochemical Technology: Applications in Electronics, ECS Fall Meeting San Antonio, October 1996.
  8. Datta, M., Symposium Co-organizer, Fundamental Aspects of Electrodeposition and Dissolution including Modeling Joint ECS/ISE Meeting, Paris, August/September 1997
  9. Datta, M., Symposium Co-organizer, Second International Symposium on Electrochemical Microsystem Technologies, Tokyo, September 1998
  10. Datta, M., Symposium Co-organizer, Electrochemical Technology in Microelectronics, ISE Meeting, Kitakyushu, Japan, September 1998
  11. Datta, M., Symposium Co-organizer, Applications of Electrochemical technology in the Electronics Industry, , 2001 Joint ECS/ISE Meeting San Francisco, September 2-7, 2001.
  12. Datta, M., Symposium Organizer, Symposium in honor of Dr. L.T. Romankiw, ECS Fall Meeting, Honolulu, Hawaii, October 2004.

Other Academic/Non-Academic Activities

Offices held in Professional Societies

  • 1999-2000: Chairman, Electrodeposition Division, Electrochemical Society, NJ.
  • 1997-1999; Treasurer/Secretary, electrodeposition division, Electrochemical Society, NJ
  • 1995-1997; Member, Ways and means committee, Electrochemical Society, NJ
  • 1997-1998: Chairman, Corrosion, Electrodeposition and surface treatment Division, International Society of Electrochemistry
  • 1994-1996: Co-chairman, Corrosion, Electrodeposition and surface treatment Division, International Society of Electrochemistry
  • 1992-1994: Councilor, Metropolitan NY Section of Electrochemical Society, NJ
  • 1991-1994: North American Editor, Processing of Advanced Materials, Chapman and Hall
  • 1991-1992: Chairman, Metropolitan NY Section of Electrochemical Society, NJ
  • 1990-1991: Vice Chairman, Metropolitan NY Section of Electrochemical Society, NJ

Major Accomplishments (Projects/Products)

  • Developed Liquid Cooling Systems for Apple’s Power Mac G5 Desktops (Cooligy)
  • Developed Micro-heat Exchangers for High Power Laser Diodes (Cooligy).
  • Developed Advanced Joining Materials and Techniques for manufacturing reliability of Data Center Cooling components (Cooligy).
  • Developed strategic directions for Lead-free, compliant Flip-Chip Technology (Intel).
  • Managed Passivation/C4 Fab operations including move to 300 mm wafers (Intel).
  • Developed electroless and electrolytic Cu deposition processes for seed layer and chip interconnects (Intel).
  • Conceived, Developed, and Transferred to IBM manufacturing the electroplated C4 (flip-chip) technology.  The plated C4 technology is now an industry standard advanced chip-package interconnection (IBM).
  • Invented and built a unique electroetching process/tool for removal of thin metal layers from wafers and demonstrated its applicability in the fabrication of C4s.    The electroetching tool is now marketed by Semitool under license from IBM (IBM).
  • Developed thin foil-type, flexible primary batteries for Smart Cards and RF-ID Tags (IBM).

Interactions with Universities

  • 1996-present: Working with Prof. Tetsuya Osaka of Waseda University, Tokyo on electrochemical processing related activities, editing books on these topics.
  • 1991 to 1999:  Adjunct Professor, Department of Chemical Engineering, University of Connecticut, Storrs, CT.
  • Co-directed graduate research work of: S-J. Jaw (Ph.D., 1996, UCONN), L.F. Vega (Ph.D., 1990, Columbia), and M. Kurdziel (M.S. 1991, Columbia),
  • 1987-1999: Developed collaboration between IBM and Universities in the NY metropolitan tri-state area in the field of electrochemical processing technologies. Coordinated and Mentored IBM’s SUR (shared university research) projects with Columbia University, NY, and Stevens Institute of Technology, NJ.
  • 1975 to 1984:  Taught Corrosion Science (with lab) and supervised graduate research, Chemical Metallurgy Lab, Swiss Federal Institute of Technology, Lausanne, Switzerland

PROFESSIONAL ACTIVITIES/ HONORS

Awards/ Honors

  • 1998 Electrodeposition Research Award of the Electrochemical Society.
  • Ninth Plateau of IBM Invention Achievement Awards.
  • IBM’s Top 5% Patent award
  • Inventor of 48 issued US patents, 9 IBM Technical Disclosure Bulletins.
  • Author of 80+ scientific papers and author/editor of several books on Electrochemical Processing & Microelectronic Packaging.
  • Organizer of International symposia; Keynote and Invited speaker.  
  • Member, IBM Technical Strategy Assessment Team for development of Low Power Technical Strategy for portable computing.
  • Chaired the Technology Working Group and Technology Implementation Group of National Electronic Manufacturing Initiative (NEMI) and developed a first of its kind technology roadmap of energy storage systems for the electronics industry.  Awarded NEMI’s leadership certificate.
  • Included in 2000 outstanding scientists of the 20th Century in honor of outstanding contribution in the field of Electrochemical Microfabrication, International Biographical Center, Cambridge, England, 1998.

Symposium Organizer/ Co-organizer

  • Symposium Organizer, Processing of Electronic Materials by Wet Etching NEPCON-West, Anaheim, CA, Feb-March 1990. 
  • Symposium Organizer, Electrochemical Microfabrication I, ECS Fall Meeting, Phoenix, October 1991
  • Symposium Co-organizer, Electrochemical Technology Applications in Electronics,  Spring Meeting, Honolulu, May 1993 (Symposium Co-Chair)
  • Symposium Organizer, Electrochemical Microfabrication –II, ECS Meeting, Miami Beach, Florida, October 1994.
  • Symposium Organizer, High Rate Metal Dissolution Processes, ECS Fall Meeting, Chicago, October 1995.
  • Symposium Co-organizer, First International Symposium on Electrochemical Microsystem Technologies, Düsseldorf, August 1996.
  • Symposium Organizer, Environmental Aspects of Electrochemical Technology: Applications in Electronics, ECS Fall Meeting San Antonio, October 1996.
  • Symposium Co-organizer, Fundamental Aspects of Electrodeposition and Dissolution including Modeling Joint ECS/ISE Meeting, Paris, August/September 1997
  • Symposium Co-organizer, Second International Symposium on Electrochemical Microsystem Technologies, Tokyo, September 1998
  • Symposium Co-organizer, Electrochemical Technology in Microelectronics,  ISE Meeting, Kitakyushu, Japan, September 1998
  • Symposium Co-organizer, Applications of Electrochemical technology in the Electronics Industry, , 2001 Joint ECS/ISE Meeting San Francisco, September 2-7, 2001.  
  • Symposium Organizer, Symposium in honor of Dr. L.T. Romankiw, ECS Fall Meeting, Honolulu, Hawaii, October 2004.

Key International Conferences (Invited Speaker/Symposium Chair/Keynote speaker)

  • Invited Speaker.  Application of Chemical and Electrochemical Micromachining in the Electronics Industry, ECS Fall Meeting, Honolulu, Hawaii, October 1987.
  • Invited Speaker. Laser Chemical Etching of Metals in Neutral Salt Solutions, MRS Symposium, Boston, December 1987.
  • Invited Speaker. Microfabrication by Electrochemical Machining, Intl. Microelectronics Conference, ISHM, Tokyo, May 1988.
  • Invited Speaker. Challenges in Electrochemical Machining Related to Surface Preparation,  NEPCON-West, Anaheim, CA, March 1989.
  • Invited Speaker. High Speed Maskless Patterning by Electrolytic Jet, AIChE Meeting San Francisco, November 1989.
  • Keynote Speaker and Symposium Chair. Processing of Electronic Materials by Wet Etching NEPCON-West, Anaheim, CA, Feb-March 1990. 
  • Keynote Speaker and Session Chair, Microfabrication by Electrodissolution, ISE meeting, Montreaux, Switzerland, August, 1991
  • Invited Speaker, Electrochemical fabrication of V-shaped nozzles for high speed printers,   Electrochemical Microfabrication I, ECS Fall Meeting, Phoenix, October 1991
  • Invited Speaker. Transport Processes During High Rate Dissolution of Metals, AIChE Meeting, Miami Beach, Florida, November 1992
  • Invited Speaker, Selective Material Removal by Wet Etching: Applications in Microfabrication, INCOSURF-92, Bangalore, December 1992
  • Invited Speaker and Session Chair, Through-Mask Electrochemical Micromachining of Thin Films ECS Spring Meeting, Honolulu, May 1993 (Symposium Co-Chair)
  • Keynote Speaker, Recent Advances in the Study of Electrochemical Micromachining, ASME Symposium on Non-Traditional Machining, Nov-Dec 1993
  • Invited Speaker, Electrochemical fabrication of mechanically robust C4s,  Electrochemical Microfabrication –II, ECS Meeting, Miami Beach, Florida, October, 1994.
  • Keynote Speaker and Session Chair, Electrochemical Micromachining in the Electronics Industry, ISE Meeting, Xiamen, China, September, 1995.
  • Keynote Speaker and Session Chair, First International Symposium on Electrochemical Microsystem Technologies, Düsseldorf, August 1996.
  • Keynote Speaker, Microfabrication by Through-Mask Electrochemical Micromachining, International Society for Optical Engineering (SPIE) meeting, Austin, September 1997.
  • Keynote Speaker and Session Chair, Maskless and Through-Mask Electrochemical Micromachining, Second International Symposium on Electrochemical Microsystem Technologies, Tokyo, September 1998
  • Electrodeposition Div. Research Award Lecture, Electrodissolution Processes: Fundamentals and Application in Microelectronics, ECS Fall Meeting Boston, November 1998.
  • Keynote Speaker and Session Chair, Electrochemical Processing Technologies in Chip Fabrication: Challenges and Opportunities, ISE Meeting, Düsseldorf, Germany, September 2002
  • Keynote Speaker, Paradigm Shifts in Microelectronics: The Role of Electrochemical Processing, Peaks in Plating, An International Symposium on Electrochemical Processes and Tools, Organized    by SemiTool, sponsored by Electrochemical Society, Semiconductor International, September 2004.
  • Invited Speaker and Session Chair, Electrochemical Processing Trends in Micro/Nano Electronics, ECS Fall Meeting, Honolulu, Hawaii, October 2004
  • Invited Speaker, Electrochemical Processing in Microelectronics, Talk presented at December 14, 2005 meeting of Santa Clara Valley Chapter of ASM International.
  • Invited Speaker, Liquid Cooling System for Advanced Microelectronics, ECS Spring Meeting, Symposium on ULSI & MEMS, Chicago, May 2007.
  • Invited Speaker, Advanced Cooling Solutions for High Power Laser Diodes and IGBTs, Thermal Management & Technology Symposium, October 20-21, 2009, Denver, Colorado. 
  • Keynote Speaker, Microfabrication by High rate Anodic Dissolution: Fundamentals and Applications, Symposium on High Rate Metal Dissolution Processes 2, 227th ECS meeting, Chicago, May 24-28, 2015.

IBM Technical Disclosure Bulletin

  • M. Datta, L.T. Romankiw, D.R. Vigliotti, R.J. von Gutfeld; Laser-jet Electrochemical Micromachining in Neutral Chloride Solution; Y08880092, IBM Technical Disclosure Bulletin, volume 32, 3A, August 1989, pp109-110.
  • M. Datta, S. Krongelb, L.T. Romankiw; Selective Etching of Cu; Y08870724, IBM Technical Disclosure Bulletin, volume 32, n11,  April August 1990, pp 231-232.
  • B. Braren, M. Datta, D. Vigliotti, R.J. von Gutfeld; One-Step Mask Making; Y08870623, Research Disclosure,  n317, September 1990.
  • B. Bumble, C. Clerc, M, Datta, R.L. Sandstorm; A Movable Multilevel Metal Mask for Depositing High temperature Super Conducting Oxide Films and Barrier Layers; Y08890355, Research Disclosure, n337, May 1992.
  • M. Datta; Fabrication of Ink-jet Printer Head Components by Through-Mask Electrochemical Micromachining, Y08910623, IBM Technical Disclosure Bulletin, volume 35, n1B, June 1992, pp453-454.
  • I-C.H. Chang, M. Datta, G.S. Frankel, W.J. Horkans; Cleaning Process for Cu(P) Anodes; Y08920123, Research Disclosure,  n344, December 1992.
  • M.J. Brady, M. Datta, P.A. Moskowitz, R.V. Shenoy; Battery Lead Configuration for Efficient Footprint Utilization, Y08940315, IBM Technical Disclosure Bulletin, volume 38, no 12, December 1995, pp 247-248.
  • E.I. Cooper, M. Datta, R.V. Shenoy, E. Tierney; Method to Monitor and Control Boil-over of Hydrogen Peroxide Based Solutions; Y08940505, IBM Technical Disclosure Bulletin, volume 38, no 12, December 1995, pp 417-418.
  • J. Cotte, M. Datta, L. Shi; Reflow of Electrochemically Fabricated C4s using Glycerol-based Water Soluble Flux; Y08940298, IBM Technical Disclosure Bulletin, volume 39, no 7, July 1996.

Membership in Professional Bodies

  1. International Society of Electrochemistry (ISE), Active Member
  2. Electrochemical Society, NJ, Active member

Student Guidance

Doctoral Students

  • “Anodic Dissolution of Iron and 304 Stainless Steel in Phosphoric Acid based solutions.”, Luis Fanor Vega, received Sc. D. degree from the School of Engineering and Applied Science, Columbia University, 1990 (The doctoral thesis work was conducted at IBM under the guidance of M. Datta, with Prof. P. Duby as the Co-guide from Columbia University).
  • “High Rate anodic Dissolution and Jet Electrochemical Micromachining of Tungsten”, Shyh-Jin Jaw, Ph.D. degree from Chemical Engineering Department, University of Connecticut, 1996 (M. Datta acted as co-advisor with Prof. James Fenton of UCONN).

Master’s Students

  • “AES/XPS Study of Transpassive Films on Molybdenum in Sulfate Solutions”, Mathew Thomas Kurdziel, Thesis in fulfillment of Master of Engineering degree from the School of Engineering and Applied Science, Columbia University, 1991 (The MS thesis work was conducted at IBM under the guidance of M. Datta, with Prof. P. Duby as the Co-guide from Coulmbia University

Others

  • North American Editor, Processing of Advanced Materials, Chapman and Hall, 1991-1994.
  • Advisory Board, Journal of Materials Processing Technology, Elsevier. 1995-1999.
  • Guest Editor, Special Issue of Processing of Advanced Materials devoted to Environmental Aspects, Volume 4, No. 4, Chapman and Hall, 1994.
  • Guest Editor, Special issue of IBM Journal of Research and Development devoted to Electrochemical Microfabrication, Volume 42, No. 5, September 1998.
207
PROGRAMS
OFFERED
5
AMRITA
CAMPUSES
15
CONSTITUENT
SCHOOLS
A
GRADE BY
NAAC, MHRD
8th
RANK(INDIA):
NIRF 2018
150+
INTERNATIONAL
PARTNERS
  • Amrita on Social Media

  • Contact us

    Amrita Vishwa Vidyapeetham
    Amritanagar, Coimbatore - 641 112
    Tamilnadu, India
    • Fax: +91-422-2686274
    • Coimbatore : +91 (422) 2685000
    • Amritapuri   : +91 (476) 280 1280
    • Bengaluru    : +91 (080) 251 83700
    • Kochi              : +91 (484) 280 1234
    • Mysuru          : +91 (821) 234 3479
    • Contact Details »