Patent ID: 8252695

Claim:
A method for fabricating a micro-electromechanical structure, comprising: (a) forming a circuitry layer on an upper surface of a first substrate, wherein the circuitry layer includes a microstructure, a release feature made of a metallic material and a pad positioned on a surface of the circuitry layer, wherein the release feature surrounds a portion of a periphery of the microstructure and penetrates the circuitry layer; (b) forming a passive layer on the circuitry layer without covering the release feature; (c) removing the release feature to expose the first substrate by a wet etching process; (d) anisotropically etching a portion of the exposed first substrate (e) disposing a second substrate above the circuitry layer; (f) forming a cavity on a lower surface of the first substrate to expose the circuitry layer under the pad; (g) filling the cavity with a polymeric material; and (h) removing a portion of the first substrate under the microstructure for releasing the micro-electromechanical structure.