Silicon microphone without dedicated backplate
US8467559B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 20, 2008 |
| Grant date | Jun 18, 2013 |
| Priority date | — |
| Expiry date | Feb 4, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2307/207
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Various embodiments of a silicon microphone sensing element without dedicated backplate are disclosed. The microphone sensing element has a circular or polygonal diaphragm with a plurality of perforated springs suspended above the front side of a conductive substrate. The diaphragm is aligned above one or more back holes in the substrate having a front opening smaller than the diaphragm. In one embodiment, a continuous perforated spring surrounds the diaphragm and has a shape that conforms to the diaphragm. A plurality of perforated beams connects the spring to rigid pads that anchor the movable diaphragm and spring. In another embodiment, there is a plurality of perforated springs having double or triple folding configurations and a plurality of perforated beams connecting the diaphragm to rigid pads. Also disclosed is a scheme to integrate the silicon microphone sensing element with CMOS devices on a single chip.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.