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.
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.