Patent ID: 7303935
Filing Date: 2007-12-04
Classification: B81C

Abstract:
1. A method of fabricating a microelectromechanical (MEM) device having a stationary element and a movable element displaceable relative to the stationary element, comprising: providing a silicon-on-insulator (SOI) wafer which includes a silicon handle layer and a silicon device layer; patterning one or more bonding pads on said wafer; providing a substrate; patterning one or more bonding pads on said substrate such that said substrate's bonding pads can be aligned with said wafer's bonding pads; etching a recessed area into said substrate; aligning said wafer's bonding pads with said substrate's bonding pads; mechanically connecting the bonding pads of said wafer and substrate to produce a thermocompression bond which bonds said wafer and substrate together to form a composite structure; underfilling gaps in said composite structure with a curable organic sacrificial material to provide mechanical support; removing said silicon handle layer from the SOI wafer to expose said silicon device layer; patterning and etching portions of said composite structure to define said stationary and movable elements such that said movable element is mechanically coupled to said stationary element; depositing, patterning and etching one or more metallization layers on said composite structure to provide electrical interconnections for said MEM device, said metallization layers comprising a conductive refractory material; and etching away said organic sacrificial layer to release said movable element.