Two types of single-crystal silicon micromechanical resonators having resonant frequencies at 150 kHz and 130 kHz were tested under harsh environment to investigate stability. To observe long-term stability, the main characteristics, such as resonant frequency and quality factor were measured over 2,500 hrs continuously while maintaining constant environmental temperature at 25℃±0.1℃. A separate experiment was also initiated to show stability during temperature cycling from -50 ℃ to 80 ℃. In both experiments, the total change in resonant frequency were less than 10 ppm and quality factor less than 10%, which demonstrates the stability of encapsulated micromechanical resonators upon exposure to harsh environments.
展开▼