A Fast Thin-Film Electret Pressure Sensor

Abstract

This paper describes a recent progress in electret pressure sensor (EPS) technology. The EPS is constructed from a flexible thin-film electret, which is coated with transversally conducting metallic layers. The EPS can be used to measure pressure changes in wide frequency range and it can be manufactured in different shapes and sizes. Laboratory measurements confirm that using a careful preamplifier design the size of the EPS can be miniaturized to one square millimetre. The calibration procedure confirms that the EPS response is linear and it can be calibrated against the piezoresistive reference sensor. The article presented some promising patents on the thin-film electret pressure sensor technology. Keywords: Electret, pressure sensors, instrumentation