Patent ID: 7863063
Filing Date: 2011-01-04
Classification: B81C

Abstract:
1. A method for fabricating a sealed cavity microstructure comprising the steps of: depositing an insulation layer with a micro-electro-mechanical structure on an upper surface of a silicon substrate, the micro-electro-mechanical structure includes at least one suspended structure and at least one conductive structure, between the suspended structure and the conductive structure is disposed a spacer region, the micro-electro-mechanical structure is clad by the insulation layer; etching the insulation layer, after the insulation layer is etched, the suspended structure and the conductive structure of the micro-electro-mechanical structure are exposed outside, and the spacer region is etched into a hollow configuration; cladding a sacrificial layer over the insulation layer, the sacrificial layer is filled into the spacer region, and the sacrificial layer is covered over the suspended structure and the conductive structure of the micro-electro-mechanical structure; performing an etching from a rear back surface of the silicon substrate and directionally forming space connecting to the spacer region; forming at least one hole in the sacrificial layer, the hole is formed over the conductive structure; depositing a cap layer over the sacrificial layer, the cap layer covers the hole of the sacrificial layer, and the cap layer contacts the conductive structure after being filled into the hole of the sacrificial layer; removing the sacrificial layer by etching, the sacrificial layer inside the spacer region, and the sacrificial layer under the cap layer are both etched through an empty space of the cap layer, and the spacer region connects with the space of the silicon substrate to achieve the suspension of the suspended structure; and depositing a sealing layer outside the cap layer to subsequently seal a clearance of the cap layer.