Micromechanical Acceleration Sensor

Abstract

A miniature silicon acceleration sensor has been developed, consisting of a capacitive accelerometer and a electronic system. A seismic mass suspended by thin bars is used as sensing element. Signal conversion is achieved by capacitance measurement to fixed electrodes. The accelerometer consists of a silicon sensor element and a glass plate with contact pads. A microelectronical processing technology is used for the fabrication of the anisotropic etching of monocrystaline silicon and simultaneously lithography on the top and on the backside of the wafers. An outline of the fabrication process is given. The sensor application take place as threshold accelerometer, that means the generation of an electrical output signal from a adjustable acceleration value.