Evaluation of a Short Microelectromechanical System Process Using a Silicon-on-Insulator Diaphragm and Anodic Bonding

Abstract

A one-chip microelectromechanical system (MEMS) fabrication process, termed as a short MEMS process, using a one-chip silicon-on-insulator (SOI) diaphragm is proposed in this study. First, an SOI-MEMS process characterized by maskless exposure was used to fabricate the SOI diaphragm. We subsequently modeled and fabricated an asymmetric micromirror using the proposed short MEMS process and the SOI diaphragm to evaluate the proposed approach. Resonance frequencies of 48 Hz and 14,840 Hz were obtained using a piezoelectric ceramic vibrating element. For a measured thickness of 11.89 µm and over-etched width of 3 µm, the scanning resonance frequencies were determined to be 52 and 15,614 Hz in the low-speed and high-speed mirror, respectively. The calculated values were in good agreement with the experimental results. This short MEMS process may be useful in fabricating a one-chip MEMS using a one-chip SOI diaphragm.