상세정보
학술대회
Open-Circuit Sensitivity Model based on Empirical Parameters for a Capacitive-type MEMS Acoustic Sensor
- 발행일
- 201509
- 출처
- International Conference on Materials and Applications for Sensors and Transducers (IC-MAST) 2015, pp.1-10
- 협약과제
- 15ZB1500, 환경 및 사용자 적응형 MEMS 마이크로폰 솔루션 개발, 양우석
- 초록
- An empirical-based open-circuit sensitivity model for a capacitive-type MEMS acoustic sensor is presented. To intuitively evaluate the characteristic of the open-circuit sensitivity, the empirical-based model is proposed and analysed by using a lumped spring-mass model and a pad test sample without a parallel plate capacitor for the parasitic capacitance. The model is composed of three different parameter groups: empirical, theoretical, and mixed data. The empirical residual stress from the measured pull-in voltage of 16.7 V and the measured surface topology of the diaphragm were extracted as +13 MPa, resulting in the effective spring constant of 110.9 N/m. The parasitic capacitance for two probing pads including the substrate part was 0.25 pF. Furthermore, to verify the proposed model, the modelled open-circuit sensitivity was compared with the measured value. The MEMS acoustic sensor had an open- circuit sensitivity of -43.0 dBV/Pa at 1 kHz with a bias of 10 V, while the modelled open- circuit sensitivity was -42.9 dBV/Pa, which showed good agreement in the range from 100 Hz to 18 kHz. This validates the empirical-based open-circuit sensitivity model for designing capacitive-type MEMS acoustic sensors.
- KSP 제안 키워드
- Acoustic Sensor, Capacitive-type, Empirical parameters, Lumped Spring-Mass Model, Open circuit, Parallel plate capacitor, Parasitic Capacitance, Proposed model, Residual Stress, Spring constant, Surface topology