Chinese Academy of Sciences

Heng Yang

Yuelin Wang

Xinxin Li

Songlin Feng

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.

MEMS device including a laterally movable portion with piezo-resistive sensing elements and electrostatic actuating elements on trench side walls, and methods for producing the same

Growing community of inventors

Shangai, China

Heng Yang