The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 23, 2009
Filed:
Jun. 11, 2007
Xinxin LI, Shanghai, CN;
Heng Yang, Shangai, CN;
Yuelin Wang, Shanghai, CN;
Songlin Feng, Shanghai, CN;
Xinxin Li, Shanghai, CN;
Heng Yang, Shangai, CN;
Yuelin Wang, Shanghai, CN;
Songlin Feng, Shanghai, CN;
Abstract
A method to create piezoresistive sensing elements and electrostatic actuator elements on trench sidewalls is disclosed. P-type doped regions are formed in the upper surface of an n-type substrate. A trench is formed in the substrate (e.g. by DRIE process) intersecting with the doped regions and defining a portion of the substrate which is movable in the plane of the substrate relative to the rest of the substrate. Then diffusion of P-type dopant into the trench side-walls creates piezoresistive elements and electrode elements for electrostatic actuation. Owing to the intersection of two doped regions, there are good electrical paths between the electrical elements on the trench side-walls and the previously P-type doped portions on the wafer surface. The trench intersects with insulating elements, so that insulating elements mutually insulate adjacent electrical elements. P-n junctions between the electrical elements and the substrate insulate the electrical elements from the substrate.