Silicon microphone with enhanced impact proof structure using bonding wires
US8045733B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 5, 2007 |
| Grant date | Oct 25, 2011 |
| Priority date | — |
| Expiry date | Aug 24, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R19/04
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A backplateless silicon microphone and a wire protection method for improved impact resistance are disclosed. A circular diaphragm is surrounded by a circular spring having a plurality of slots and perforations to facilitate air damping reduction, release of in-plane stress, and improve out-plane flexibility. Anchored at a substrate, the circular spring holds the silicon microphone suspended over a backside hole in the substrate but allows the diaphragm to vibrate perpendicular to the substrate. A microphone variable capacitor is formed between the perforated spring and substrate. Slot size is minimized to prevent particles from entering an underlying air gap. A plurality of “n” bonding pads near the outer edge of the circular spring are connected by “n/2” bonding wires that serve as a stopper to restrict an upward motion of the diaphragm. The bonding wires may cross each other to enable lower loop height for more effective resistance to impact.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.