Low-Noise MEMS Vibration Sensor for Geophysical Applications

Abstract

The need exists for high sensitivity, low noise vibration sensors for various applications such as geophysical data collection, tracking vehicles, intrusion detectors, and underwater pressure gradient detection. In general, these sensors differ from classical accelerometers in that they require no DC response, but must have a very low noise floor over a required bandwidth. Theory indicates a capacitive micromachined silicon vibration sensor can have a noise floor on the order of 0. I gl ../Hz over I kHz bandwidth while reducing size and weight JO-fold compared to existing magnetic geophones.