Gas Pressure Sensing Based on MEMS Resonators

MEMS resonators bear great potential for applications as RF sensors, filters and oscillators, e.g., in life sciences or information technology. Resonant AlN and SiC beams with operation frequencies between 0.01 and 3.4 MHz have been prepared using a semiconductor fabrication process. The metallized beams were actuated in a permanent magnetic field of about 0.5 T by the Lorentz force. The resonant response was detected in the frequency domain. Resonator geometry and material were varied to attain a generalized understanding of the RF performance in dependence of the ambient pressure. In particular the quality factor shows a high sensitivity on pressure, allowing potential application as absolute pressure sensor. Theoretical models have been applied that match well to the measurement.