Patent ID: 7258018

Claim:
A semiconductor chip for use in fabricating pressure transducers, comprising: a semiconductor wafer having a top and a bottom surface, a layer of an insulating material formed on said top surface, said bottom surface having at least two recesses of equal dimensions and spaced apart, said recesses providing a first and second equal thin active areas, which areas deflect upon application to a force applied to said top surface; a first plurality of piezoresistive devices arranged in a given pattern and positioned on said insulating material and located within said first active area; a second equal plurality of piezoresistive devices arranged in the identical pattern and located on said insulating material within said second active area; first connecting means for connecting said first plurality of piezoresistive devices in a first array; second connecting means for connecting said second plurality of piezoresistive devices in a second array corresponding to said first array; a glass pedestal bonded to the bottom surface of said semiconductor wafer to provide a support for said semiconductor wafer; a first recess on the top surface of said glass pedestal and positioned about said first active area, and a second recess on the top surface of said glass pedestal and positioned about said second active area; and a first boss extending from said bottom surface of said wafer and symmetrically positioned with said first active area and operative to impinge upon said glass pedestal surface within said first recess when a force in excess of a predetermined force is applied to said top surface, and a second boss symmetrical to said first boss and also extending from said bottom surface of the wafer and also symmetrically positioned as said first boss within said second active area and operative as said first boss.