METHOD OF MANUFACTURING A MEMS MICROPHONE

摘要

A method of fabricating a micro electrical-mechanical system (MEMS) microphone on a substrate includes forming a sacrificial layer on a front surface of the substrate, forming a membrane within the sacrificial layer, forming a fixed plate on the sacrificial layer at a location corresponding to a location of the membrane, performing a laser cutting on the back surface of the substrate at a location corresponding to an edge region of the fixed plate until a surface of the sacrificial layer is expose to form an opening, forming a patterned photoresist layer on the back surface exposing a region within the boundary of the opening, removing a portion of the back surface using the patterned photoresist layer as a mask to form a cavity, and removing a portion of the sacrificial layer above and below the membrane to form an air gap between the membrane and the fixed plate.

主权项

1. A method of manufacturing a micro electromechanical system (MEMS) microphone, the method comprising:
providing a semiconductor substrate having a front surface and a back surface; forming a sacrificial layer on the front surface of the semiconductor substrate; forming a membrane within the sacrificial layer; forming a fixed plate on the sacrificial layer at a location corresponding to a location of the membrane; performing a laser cutting on the back surface of the semiconductor substrate at a location corresponding to an edge region of the fixed plate until a surface of the sacrificial layer is exposed to form an opening; forming a patterned photoresist layer on the back surface of the semiconductor substrate exposing a region within a boundary of the opening, removing a portion of the back surface of the semiconductor substrate using the patterned photoresist layer as a mask until the surface of the sacrificial layer is exposed to form a cavity; and removing a portion of the sacrificial layer disposed above and below a center region of the membrane to form an air gap between the membrane and the fixed plate.