High modulus polycrystalline 3C-SiC technology for RF MEMS

In this paper, we present substantial progress toward achieving a high modulus poly-SiC technology which lays the groundwork for SiC-based microresonators. We report the development of a single-precursor, in situ doped SiC low-pressure chemical vapor deposition (LPCVD) process in a commercial horizontal reactor, as well as the development of a highly selective reactive ion etching process for SiC with the highest reported etch selectivity to SiO/sub 2/. Folded-flexure SiC comb-drive resonators are fabricated and tested at audio frequencies. The measured acoustic velocity of 15 km/s and Young's modulus of 710 GPa are the highest reported to date for poly-SiC films.