Effects of Mechanical Vibrations and Bias Voltage Noise on Phase Noise of MEMS Resonator Based Oscillators

Micromechanical Resonator based oscillators are a promising technology for replacing quartz crystal based oscillators. In this work, we will report the effects of mechanical vibrations and bias voltage noise on the phase noise performance of electrostatic MEMS resonator based oscillators. Accurate models for both these effects are discussed along with their experimental verification using a 1.3MHz, epi-silicon encapsulated Single Anchored Double Ended Tuning Fork (DETF) resonator. The acceleration sensitivity of the resonator was found to be < 10ppb/g which is better than many low cost crystal resonators, and shows potential for improvement to get performance which is at par or better than quartz crystal oscillators.