Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
ELECTRET CAPACITOR
Document Type and Number:
Japanese Patent JP2005191208
Kind Code:
A
Abstract:

To provide a small-size, highly reliable, and high performance electret capacitor which shows excellent moisture-proof characteristic and includes an electret formed of silicon oxide film.

The electret capacitor comprises a first electrode 11 in which an empty hole 10 is formed, an air gap 15 connected to the empty hole, and a second electrode 16. The electret film formed of silicon oxide film 4 is formed to the first electrode, and the air gap 15 and electret are formed between the first electrode and the second electrode. In the electret film, an insulating film is formed to the upper surface and lower surface of the silicon oxide film and the second electrode operates as an vibrating film.


Inventors:
YAMAOKA TORU
OGURA HIROSHI
Application Number:
JP2003429469A
Publication Date:
July 14, 2005
Filing Date:
December 25, 2003
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
MATSUSHITA ELECTRIC IND CO LTD
International Classes:
H01G7/02; (IPC1-7): H01G7/02
Attorney, Agent or Firm:
Fumio Iwahashi
Tomoyasu Sakaguchi
Hiroki Naito