P-170: Micro-Mirror Array Fabricated by the CMOS Process for Applications of MEMS Display

This article describes a micro‐mirror array fabricated using the commercial 0.35μm CMOS (complementary metal oxide semiconductor) process and a simple maskless post‐process. The material of the micro‐mirror is aluminum and the sacrificial layer is silicon dioxide. The fabrication of the micro‐mirror array is compatible with the CMOS process, so the mirror array has a potential to integrate with circuitry on a chip. The post‐process utilize the BOE (buffered oxide etching) to remove the sacrificial layer and to suspend the micro mirror. The micro‐mirror contains a circular membrane and has four fixed beam. There are four fan‐ shaped electrodes below the micro mirror which is utilized to drive the micro mirror tilted. Each micro mirror has four rotatable directions and each direction is independent. Experimental results show the mirror has a tilting angle of about 0.93 ° at a driving voltage of 30 V.