Method of forming semiconductor device structure

A method for forming a semiconductor structure, comprising:

• forming a first dielectric layer over a substrate;
• forming a first recess and a second recess in the first dielectric layer;
• forming a first movable membrane over the first dielectric layer, wherein the first movable membrane has a first corrugated portion formed over the first recess and a first recessed portion formed over the second recess;
• forming a second dielectric layer over the first movable membrane;
• and
• forming a cavity through the substrate, the first dielectric layer, and the second dielectric layer to expose first recessed portion and to partially expose the first corrugated portion of the first movable membrane.

A method for forming a semiconductor device structure, comprising:

• forming a first dielectric layer over a semiconductor substrate;
• partially removing the first dielectric layer to form first recesses;
• forming a first membrane over the first dielectric layer, wherein the first membrane fills the first recesses so that the first membrane comprises first corrugated portions;
• forming a second dielectric layer over the first dielectric layer to cover the first corrugated portions;
• and
• partially removing the semiconductor substrate, the first dielectric layer, and the second dielectric layer to form a cavity partially exposing the first corrugated portions.