Development and application of planar piezoresistive vibration sensor

•A micromachined planar piezoresistive vibration sensor has been developed.•The sensor was fabricated with less process cost and difficulties in packaging.•Vibration sensor exhibited performance comparable to a commercial sensor device.

By using the surface piezoresistor diffusion method and front-side-releasing micromachining technique, we successfully developed a planar piezoresistive vibration sensor with less process cost, simple structure and less package difficulties. The functional features of the fabricated planar vibration sensors, including the amplitude–frequency response and random vibration response, have been evaluated comprehensively. As the results shown, the vibration sensor has reasonably good sensitivity performance (Min. detectable acceleration: 0.01 g at the Min. responsible frequency of 4 Hz; stable output at the measured signal with frequency >6 Hz and amplitude >0.05 g) for many applications: e.g. as the motion sensor for checking the health condition of human beings, or as the monitor sensor for monitoring the safety and security of infrastructure.

Graphical abstractA high performance planar piezoresistive vibration sensor with less process cost, simple structure and less package difficulties.Figure optionsDownload full-size imageDownload as PowerPoint slide