Stiction resistant mems device and method of operation
US9190937B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 6, 2013 |
| Grant date | Nov 17, 2015 |
| Priority date | — |
| Expiry date | Feb 14, 2034 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB81B2203/058
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A MEMS device (20) includes a movable element (20) suspended above a substrate (22) by a spring member (34) having a spring constant (104). A spring softening voltage (58) is applied to electrodes (24, 26) facing the movable element (20) during a powered mode (100) to decrease the stiffness of the spring member (34) and thereby increase the sensitivity of the movable element (32) to an input stimulus (46). Upon detection of a stiction condition (112), the spring softening voltage (58) is effectively removed to enable recovery of the movable element (32) from the stiction condition (112). A higher mechanical spring constant (104) yields a stiffer spring (34) having a larger restoring force (122) in the unpowered mode (96) in order to enable recovery from the stiction condition (112). A feedback voltage (56) can be applied to feedback electrodes (28, 30) facing the movable element (32) to provide electrical damping.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.