Highly sensitive triaxial silicon accelerometer with integrated PZT thin film detectors

This paper reports the first micromachined triaxial single-mass accelerometer with integrated piezoelectric thin film detectors. In addition, the design has a much higher sensitivity than previously presented approaches and is significantly smaller. The keystones of the performance are the use of the highly sensitive PZT material and the deep reactive ion etching (DRIE)-based process flow utilizing silicon-on-insulator (SOI) wafers. The accelerometer consists of a 1.2 mg seismic mass, supported by four 8 mum thick spokes. The charge sensitivity in the vertical direction is 22 pC/g and in the parallel direction 8 pC/g. (C) 2001 Elsevier Science B.V. All rights reserved.