Abstract: There is disclosed a spreading resistance piezoresistive transducer which employs a planar diaphragm member fabricated from a semiconductor material and having deposited on a surface thereof at least three contact areas. A first contact area is located central to the diaphragm with a second area near the periphery of the diaphragm. A third contact is of a larger area and is positioned between the first and second contacts. A source of biasing potential is applied between the first and second contacts to cause current flow indicative of the spreading resistance between the contacts. The value of the spreading resistance varies in accordance with a force applied to the diaphragm.

Abstract: A monocrystalline silicon substrate has formed on a surface a grating pattern manifested by a series of parallel grooves, a layer of dielectric is thermally grown on said surface to replicate said pattern on an opposite surface of said dielectric and a layer of silicon deposited on said opposite surface of said dielectric is single crystal silicon determined by said grating. The structure formed enables the deposited single crystal layer to be selectively treated to provide at least one piezoresistive sensing element to thereby provide a transducer having both the force collector or substrate and the sensing elements of single crystal silicon and dielectrically isolated by means of said dielectric layer.

Abstract: A pressure transducer employs a semiconductor diaphragm with a top surface having located thereon a central boss area of a trapezoidal cross section surrounded or "framed" by a continuous groove of a predetermined width. Piezoresistive sensors are formed on the bottom surface of said diaphragm with a first sensor adjacent the outer edge of said groove and another sensor parallel to said first sensor and adjacent the inner edge of said groove, said groove operative as a stress concentrating area to enable said sensors to provide a relatively large linear output upon application of a force to said diaphragm.

Abstract: A transducer assembly for measuring absolute pressure utilizing a glass substrate and a thin silicon diaphragm upon which is diffused a piezoresistive bridge circuit. Bridge circuit components are properly oriented and connected to bonding pads formed on the silicon. The glass substrate has a circular well formed therein having a diameter at least as large as the diameter of the diaphragm. Conducting leads are deposited on the glass substrate in a pattern matching that of the bonding pads on the silicon. The silicon is bonded to the glass substrate with the silicon diaphragm overlying the well in the glass and the bonding pads overlying the conducting leads deposited on the glass. The bond provides a hermetic seal around the well, trapping a predetermined pressure therein which serves as a reference pressure. Ambient pressure variations cause stress variation in the diaphragm, resulting in unbalance of the bridge which can be sensed with associated circuits to give an indication of the ambient pressure.