상세정보
학술대회
Sensing Gap Reconfigurable Capacitivie Type MEMS Accelerometer
- 발행일
- 200712
- 출처
- Device and Process Technologies for Microelectronics, MEMS, Photonics, and Nanotechnology IV (SPIE 6800), v.6800, pp.1-7
- 협약과제
- 08MB1900, 유비쿼터스용 CMOS 기반 MEMS 복합센서기술개발, 최창억
- 초록
- A novel sensing gap reconfigurable capacitive type MEMS accelerometer with high sensitivity and high resolution is designed, fabricated and characterized. The present MEMS accelerometer is fabricated by using simple SOI processDRIE. However, conventional Silicon on Insulator (SOI) process is hard to make patterns which is smaller than 1 um because of its high aspect ratio and ICP etching error such as loading-effect and under-cutting. So we have adopted a simple idea of the MEMS actuator-stopper system to modulate the sensing gap precisely. Unlike previous capacitive type MEMS accelerometer which has an anchored reference comb electrodes, the proposed accelerometer has a movable reference comb with MEMS electrostatic actuators and stoppers. By simply applying DC bias to MEMS actuators, the reference comb electrode is moved to the sensing comb structure until the actuators contacting the stoppers. The gap between sensing comb fingers and reference comb fingers is reduced by the gap between actuators and stoppers. In this paper, the initial sensing gap is 1.5um and it reduced to 0.5um, when working. Then, the overall capacitance and sensitivity is simple increased. The capacitance is increased from 3.47pF at the OFF state to 5.35pF at the ON state by applying 2V DC bias.
- KSP 제안 키워드
- Capacitive-type, Electrostatic actuators, High Sensitivity, High aspect ratio, High-resolution, ICP etching, MEMS accelerometers, MEMS actuators, Off-State, Silicon On Insulator(SOI), Stopper system