October 1, 2009
Amrita School of Engineering, Coimbatore
Students from the Amrita School of Engineering, Coimbatore won the first prize for their ground-breaking design project at a National-Level Technical Symposium in August*.
The competition, organized by Bannari Amman Institute of Technology, Erode District in Tamil Nadu, drew 92 contestant teams from all over India.
Final year Polymer Engineering students C. Raja Sundar, M. Aravind and B. Arun received a cheque for Rs. 50,000 for their Design Project / Model titled, Design and Fabrication of a Spin Coater Machine for Thin Film Coating and its Potential Applications.
Spin coating is the preferred method for application of thin, uniform films to flat substrates.
The spin coating process used to deposit photoresist onto wafers is one of the most mature processes in modern semiconductor manufacturing. As integrated circuits get smaller and smaller, lithography processes require increasingly uniform photoresist layers. Many researchers have conducted studies into understanding the spin coating process and its superiority over other techniques has been well established.
The students’ aim was to design and fabricate a low-cost spin coater with the ability to coat thin films onto any suitable substrate held by vacuum.
Commercially available manual spin coaters are expensive but the Amrita students made an innovative coater for less than $50, which uses a vacuum chuck to hold the substrate.
Their spin coater can efficiently run at 10,000 rpm and even has the capability of running at speeds greater than 20,000 rpm. The machine is vibration-free and stable even at such high speeds.
“The process involves depositing a small puddle of a fluid onto the center of a substrate by a robotic arm and then spinning the substrate at high speeds in order to spread the fluid by centrifugal force,” the students explained. “The physics behind spin coating involves a balance between centrifugal forces controlled by spin speed and viscous forces, that are determined by solvent viscosity.”
The students’ spin coater machine is both portable and precise. Film thicknesses can be changed easily by changing the spin speed.
We congratulate the engineering students at Coimbatore for having created a machine that will potentially set new bench marks for student industrial design all over the world.
* Subsequently, the Spin Coater Machine also bagged the first prize in a Project Design Contest at SHASTRA 09, an International Symposium organised by IIT Madras during Sep 30 – Oct 4, 2009. This time the students received a cash award of Rs. 15,000.