Patent · US Expired

Electret condenser

US7853027B2 · kind B2 · utility

9Cited by
10References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 7, 2005
Grant dateDec 14, 2010
Priority date
Expiry dateMar 1, 2026

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB81C2201/112
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An electric condenser includes a fixed film 110 including a conductive film 118 to be an upper electrode, a vibrating film 112 including a lower electrode 104 and a silicon oxide film 105 to be an electric film, and a silicon oxide film 108 provided between the fixed film 110 and the vibrating film 112 and including an air gap 109. Respective parts of the fixed film 110 and the vibrating film 112 exposed in the air gap 109 are formed of silicon nitride films 106 and 114.

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