Experimental investigation of temperature and relative humidity effects on resonance frequency and quality factor of CMOS-MEMS paddle resonator

Abstract

This paper reports an experimental approach to analyse the performance of an externally actuated CMOS-MEMS paddle resonator with proof mass. The surface morphology test of the device is performed with the help of field emission scanning electron microscopy (FESEM), before and after the reliability tests. The effects of temperature variation on the resonance frequency response of the fabricated CMOS-MEMS resonator is analysed under the variation of temperature from 25°C to 80°C inside a custom made environmental chamber at a constant relative humidity (32%RH). In the next step, the variation in the quality factor of the MEMS resonator is studied under the effect of varying temperature. Finally, the resonance frequency behavior is analysed under the variation of relative humidity from 32%RH to 90%RH at a constant temperature of 25°C. The device is found to be eroded and there are some wastes of humidity on it. A total change of 6.9Hz in resonance frequency is recorded from 25°C to 80°C. The drop in the resonance frequency of the MEMS device is found to be 137MHz/°C with the rise in temperature. Under the temperature variation from 25°C to 80°C, the quality factor is found to be nonlinear. A total change of 1.3Hz in the resonance frequency is observed from 32%RH to 90%RH. The resonance frequency is found to be −21.8MHz/RH% with an increasing humidity level.