Computer Engineering Commons^™

Novel Microelectromechanical Systems Image Reversal Fabrication Process Based On Robust Su-8 Masking Layers, Scott A. Ostrow Ii, Ronald A. Coutu Jr.

Electrical and Computer Engineering Faculty Research and Publications

This paper discusses a novel fabrication process that uses a combination of negative and positive photoresists with positive tone photomasks, resulting in masking layers suitable for bulk micromachining high-aspect ratio microelectromechanical systems (MEMS) devices. MicroChem's negative photoresist Nano™ SU-8 and Clariant's image reversal photoresist AZ 5214E are utilized, along with a barrier layer, to effectively convert a positive photomask into a negative image. This technique utilizes standard photolithography chemicals, equipment, and processes, and opens the door for creating complementary MEMS structures without added fabrication delay and cost. Furthermore, the SU-8 masking layer is robust enough to withstand aggressive etch chemistries …