Stiction reduction system and method thereof
US11661332B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 19, 2020 |
| Grant date | May 30, 2023 |
| Priority date | — |
| Expiry date | Feb 19, 2040 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB81C2201/115
- WIPO fieldMicro-structural and nano-technology
- WIPO sectorChemistry
Abstract
Methods and systems for reducing stiction through roughening the surface and reducing the contact area in MEMS devices are disclosed. A method includes fabricating bumpstops on a surface of a MEMS device substrate to reduce stiction. Another method is directed to applying roughening etchant to a surface of a silicon substrate to enhance roughness after cavity etch and before removal of hardmask. Another embodiment described herein is directed to a method to reduce contact area between proof mass and UCAV (“upper cavity”) substrate surface with minimal impact on the cavity volume by introducing a shallow etch process step and maintaining high pressure in accelerometer cavity. Another method is described as to increasing the surface roughness of a UCAV substrate surface by depositing a rough layer (e.g. polysilicon) on the surface of the substrate and etching back the rough layer to transfer the roughness.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.