Post-CMOS chip-level processing for high-aspect-ratio microprobe fabrication utilizing pulse plating

摘要

A post-CMOS process for chip-level monolithic integration has been developed. A metal probe array for recording neural signals is utilized as a test vehicle to realize the integration process. This probe array is fabricated on a 2 mm x 2 mm chip containing eight ultra-low power CMOS operational amplifiers. A LIGA-like process is employed utilizing UV lithography on SU-8 photoresist and pulse electroplating technique. Pulse plating significantly reduces stress in the deposited material. The post-CMOS fabrication process is utilized to fabricate 70 μm high probes having different aspect-ratios that are monolithically integrated on the CMOS chip.