Patent ID: 7550358

Claim:
A process for forming a MEMS device including a portion movable laterally in the plane of the device, the method including the steps of: forming electrically insulating elements extending through a substrate of a first conductivity type; doping regions of the surface of said substrate with a dopant of a second conductivity type opposite to said first conductivity type, to form doped regions of the surface of said substrate; forming at least one trench in said substrate intersecting with said electrically insulating elements and said doped regions and defining said movable portion of said substrate which is arranged for movement in the plane of the surface of said substrate, said electrically insulating elements extending through the thickness of said laterally movable portion; and effecting diffusion of dopant of said second conductivity type into side walls of said at least one trench to form one or more piezo-resistive sensing elements for detecting motion of said movable portion of said substrate and/or one or more electrostatic actuator elements for moving said movable portion of said substrate, whereby electric contact is achieved between said doped regions on said trench side walls and said doped regions on the surface by intersection of said doped regions on said trench side walls with said doped regions on the surface.