Design of a poly silicon MEMS microphone for high signal-to-noise ratio

Author

Dehe, A. ; Wurzer, Martin ; Fuldner, Marc ; Krumbein, Ulrich

Author_Institution

Infineon Technol. AG, Munich, Germany

fYear

2013

fDate

16-20 Sept. 2013

Firstpage

292

Lastpage

295

Abstract

This paper reports on the state of the art silicon micromachined microphone utilizing a dual poly silicon membrane system. MEMS chips from 1.4mm down to 1.0mm side length are applied for mobile communication. Design aspects related with key performance parameters such as sensitivity, signal to noise ration and distortion are discussed. Sensitivity of - 38BV/Pa is achieved for different microphone membrane diameters. A maximum signal to noise ration of 66dB(A) for the largest system could be achieved. The perfect fit of simulation versus measurements enables deeper analysis and balancing of noise contributors. Environmental noise suppression of 5dB by acoustical high pass design is demonstrated.

Keywords

interference suppression; membranes; micromechanical devices; microphones; MEMS chips; acoustical high pass design; distortion; dual poly silicon membrane system; environmental noise suppression; microphone membrane diameters; mobile communication; noise contributors; sensitivity; signal to noise ratio; silicon micromachined microphone; size 1.4 mm to 1.0 mm; Application specific integrated circuits; Micromechanical devices; Microphones; Noise; Sensitivity; Silicon; Ventilation; membrane; microphone; noise suppression; signal to noise ratio; silicon MEMS;

fLanguage

English

Publisher

ieee

Conference_Titel

Solid-State Device Research Conference (ESSDERC), 2013 Proceedings of the European

Conference_Location

Bucharest

Type

conf

DOI

10.1109/ESSDERC.2013.6818876

Filename

6818876