US Patent 7647833 Filled dielectric on metal pressure sensor

A pressure sensing apparatus (1) includes an elastically deformable pressure-sensitive diaphragm assembly (13) having a pressure-sensitive metal or metal alloy diaphragm (14). A functional filled dielectric layer (25) is on the diaphragm and includes a base dielectric material and at least one CTE raising filler. A CTE of the functional filled dielectric layer provides a CTE @ 800° C.≧8 ppm/° C., such as ≧10 ppm/° C. A plurality of piezoresistive elements (27) are on the functional filled dielectric layer (25).