Patent ID: 7622782
Filing Date: 2009-11-24
Classification: B81B,B81C,G01L,Y10S

Abstract:
1. A pressure sensor comprising: a base substrate comprising first and second support portions, facing surfaces of the first and second support portions comprising walls defining a first cavity, the base substrate further comprising a diaphragm portion extending between top portions of the first and second support portions, wherein the base substrate comprises silicon and wherein the first cavity is open to an environment to be sensed; at least one bottom dielectric layer disposed on an underside of each support portion of the base substrate that do not extend past edges of the undersides of the support portions; a cap substrate comprising silicon; a silicon fusion bond between the cap substrate and the base substrate; a chamber disposed between the base substrate and the cap substrate, wherein the chamber is hermetically sealed from the environment by the silicon fusion bond; a piezo-resistive element disposed in physical communication with the diaphragm portion between the chamber and the first cavity; and a conductive pathway implanted between the base substrate and the at least one top dielectric layer, the conductive pathway connected to and extending from the piezo-resistive element to a portion of the base substrate beyond an outer edge of the cap substrate.