Fabrication of high-aspect-ratio electrode array by combining UV-LIGA with micro electro-discharge machining

In this paper, the combination of UV-LIGA with the Micro electro-discharge machining (Micro-EDM) process was investigated to fabricate high-aspect-ratio electrode array, and an easy and rapid process for fabricating ultra-thick SU-8 microstructures up to millimeter depth was described. First, the modified UV-LIGA process was used to fabricate the copper hole array, and then the hole array electrode was employed as a tool in the Micro-EDM process to fabricate the multiple-tipped electrodes. Electrode array of various shapes have been fabricated by this technique. The aspect ratio is up to 17.65.