MEMS microphone and preparation method therefor
US12022270B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 26, 2020 |
| Grant date | Jun 25, 2024 |
| Priority date | — |
| Expiry date | Dec 11, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2201/003
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A preparation method for a micro-electromechanical systems (MEMS) microphone includes the steps of: providing a silicon substrate having a silicon surface; forming an enclosed cavity in the silicon substrate; forming a plurality of spaced apart acoustic holes in the silicon substrate, each acoustic hole having two openings, one of which communicating with the cavity and the other one located on the silicon surface; forming a sacrificial layer on the silicon substrate, which includes a first filling portion, a second filling portion and a shielding portion; forming a polysilicon layer on the shielding portion; forming a recess in the silicon substrate on the side away from the silicon surface; and removing the first filling portion, the second filling portion and part of the shielding portion so that the recess is brought into communication with the cavity to form a back chamber, and that the polysilicon layer, the remainder of the shielding portion and the silicon substrate together delimit a hollow chamber, the hollow chamber communicating with the opening of the plurality of acoustic holes away from the cavity, completing the MEMS microphone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.