Variable area capacitive lateral acceleration sensor and preparation method thereof

Abstract

The present invention provides a variable area capacitive lateral acceleration sensor and a preparation method. The acceleration sensor at least includes: three-layer stack structure bonded by a first substrate, a second substrate and a third substrate which are electrically isolated with each other, wherein, the second substrate includes a movable seismic mass, a frame surrounded the movable seismic mass, a elastic beam connected to the movable seismic mass and the frame, a plurality of bar structure electrodes positioned on two surfaces of the movable seismic mass, an anti-overloading structure arranged on the movable seismic mass, etc.; the plurality of first bar structure electrodes on the first substrate and a plurality of second bar structure electrodes on one surface of the second substrate form capacitor structure, the plurality of third bar structure electrodes on the third substrate and a plurality of second bar structure electrodes on one surface of the second substrate form capacitor structure, and those two capacitor form differential sensitive capacitor structure. The present invention has the advantage of high sensitivity and good linearity, and different kinds of beam shapes may be designed as needed, to prepare capacitive acceleration sensors with different sensitivity, and the preparation has high flexibility.