Patent ID: 8464589

Claim:
A micro-electromechanical systems (MEMS) structure, comprising: a substrate, having a front side and a back side, wherein the substrate have a predeteimined region; a structural dielectric layer, disposed over the front side of the substrate; a diaphragm, held by the structural dielectric layer at a peripheral end, wherein the diaphragm is above the substrate corresponding to the predeteimined region and forms a chamber between the substrate and the diaphragm, the chamber is connected to an outer space by multiple through holes in the substrate or in a structure layer on the front side of the substrate, or in both the substrate and the structure layer, wherein the diaphragm comprises: a plurality of trench/ridge rings at a peripheral region surrounding a central region of the diaphragm; and a corrugated structure, located at the central region of the diaphragm, surrounded by the trench/ridge rings.