Monolithic micromechanical vibrating beam accelerometer with trimmable resonant frequency
US5605598A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 13, 1994 |
| Grant date | Feb 25, 1997 |
| Priority date | — |
| Expiry date | May 13, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P2015/0831
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A monolithic, micromechanical vibrating beam accelerometer with a trimmable resonant frequency is fabricated from a silicon substrate which has been selectively etched to provide a resonant structure suspended over an etched pit. The resonant structure comprises an acceleration sensitive mass and at least two flexible elements having resonant frequencies. Each of the flexible elements is disposed generally collinear with at least one acceleration sensitive axis of the accelerometer. One end of at least one of the flexible elements is attached to a tension relief beam for providing stress relief of tensile forces created during the fabrication process. Mass support beams having a high aspect ratio support the mass over the etched pit while allowing the mass to move freely in the direction collinear with the flexible elements. Also disclosed is a method for fabricating such an accelerometer. Further disclosed is an alternative embodiment of the aforementioned accelerometer characterized by a low profile, and alternative planar processing methods for fabrication of these and other embodiments.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.