Convention Paper
Surface-Micromachined MEMS Microphone
AES Convention 115 · Paper 5889 · October 2003
Abstract
The term MEMS is an acronym for MicroElectroMechanical Systems. During the past decade numerous novel sensor devices based on MEMS technologies have been made: accelerometers for air-bag deployment detection, MEMS mirror arrays for Digital Light Processing (DLP) projectors, and inkjet printer heads to name a few well known devices. MEMS devices have been developed for data storage, wireless communication, displays, optical switching, as well as microfluidics, aerospace and biomedical applications. The application of MEMS technology to audio has been primarily focussed on microphones. There are two major application areas that are driving the interest in MEMS microphones: hearing aids where size and integration with signal processing are important, and consumer devices where there is interest in reducing costs by integrating a complete systems solution on an integrated circuit and packaging of devices to allow standard robotic pick-and-place manufacturing. This paper describes a MEMS microphone that was built at Bell Labs which was the first all-surface machined MEMS microphone. We also describe some fundamental issues in the design of MEMS microphones.
