The stability of resonant frequency for single wafer, thin film encapsulated silicon MEMS resonators was investigated for both long term operation and temperature cycling. The resonant frequencies of encapsulated resonators were periocidcally measured at 25°C ± 0.1°C for > 9,000 hours, and the resonant frequency variation remained within the measurement uncertainty of 3.1 ppm and 3.8 ppm. Also,...
