Improvement of Surface Roughness and Optical Scattering Loss for a MEMS Micro-Mirror Switch

초록

It is very important for MEMS optical switch to have a surface optically smooth and efficient enough to get negligible optical scattering loss by developing processes of plasma etch and deposition. We report on the optimization of surface roughness and optical property in etched Si-surface and gold-sputtered Si-surface by trying various etch chemistries of (Cl2, CF4, SF6) and gold sputtering conditions. Optically efficient Si-surface not only with low roughness of less than 15nm but also with vertical etch profile was obtained at optimized etch processes with high etch rate of 800 nm/min. This result is applied to the fabrication of a simple and efficient MEMS micro-mirror switch.