PECVD SiC as a Chemical Resistant Material in MEMS

Silicon carbide (SiC) is a promising material for the device operating in hash environment, such as high temperature, high pressure or erodent environment, owning to its excellent electrical, mechanical, and chemical properties. The PECVD process allows deposition of SiC at low temperature (200degC-400degC), which makes SiC has better compatibility in Post-CMOS processes. In this paper, PECVD SiC has been investigated as a chemical resistant material in MEMS systematically. SiC was utilized as a coating layer to protect micromachined polysilicon devices from erosive environment and as a wet-etch mask to pattern silicon and glass. SiC was also used to construct microstructures taking the merit of SiC´s chemical stability.