Patent · US Expired

Capacitive microphone and method therefor

US5889872A · kind A · utility

88Cited by
2References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 2, 1996
Grant dateMar 30, 1999
Priority date
Expiry dateJul 2, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04R19/016
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A capacitive microphone (10) utilizes a polysilicon diaphragm (14) that overlies an atmospheric cavity (34). The diaphragm is doped and annealed to form a sensitivity of the microphone (10). A silicon cap covers and protects the diaphragm (14) and a fixed plate (18).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.