Temperature and humidity effects on the quality factor of a silicon lateral rotary micro-resonator in atmospheric air

The temperature and humidity dependence of the quality factor of MEMS lateral rotary resonators operating in atmospheric air was analyzed and measured. The quality factor of a monocrystalline silicon lateral rotary micro-resonator was analytically modeled and numerically evaluated based on air shear damping loss mechanisms. The effect of temperature and humidity on each air damping mechanism was attributed to the thermophysical properties of humid air. The damping model predicted qualitatively the experimental results for a large range of temperature (from 20°C to 80°C) and humidity (from 30% to 90% RH). These environmental effects can be taken into account for the design of MEMS devices operating in air, such as chemical microsensors.