Patent ID: 7478562

Claim:
A high temperature pressure variable capacitor, comprising: a first high temperature semiconductor wafer having a top and bottom surface and having a first conductive capacitor plate positioned on the top surface, said first wafer of a thickness enabling deflection upon application of a force to said bottom surface thus acting as a diaphragm; a dielectric layer covering said top surface and said plate; a second high temperature semiconductor wafer having atop and bottom surface and having a plate-accommodating depression etched into the top surface to a given depth, a second conductive plate located in said depression and relatively congruent to said first plate, said top surface of said first wafer bonded to said top surface of said second wafer, with said second plate facing said first plate and separated therefrom by a gap, said gap forming a capacitor between said first and second plates, whereby when a force is applied to the bottom surface of said first wafer said diaphragm deflects to change the gap between said plates and a capacitance between said first and second plates.