Patent ID: 8216434
Filing Date: 2012-07-10
Classification: B81C,G01N

Abstract:
1. A method of fabricating a micromachined shear stress sensor, the method comprising: depositing a layer of silicon nitride on a substrate and etching the substrate to form a cavity having an overlying diaphragm, the substrate having a front-side surface and a backside surface; performing reactive ion etching on the diaphragm to create a plurality of access slits on the diaphragm; conformally depositing a layer of polysilicon on the substrate, then doping the polysilicon layer with phosphorus; sputtering a layer of aluminum onto the backside surface of the substrate, and patterning the aluminum layer to form a plurality of electrode leads; patterning the polysilicon layer on the front-side surface of the substrate to form a strip of heat sensing element; and connecting a plurality of wire bonds between the sensing element on the front-side surface and the electrode leads on the backside surface, by passing the wire bonds through the access slits on the diaphragm.