Monolithic micromechanical accelerometer
US5126812A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 23, 1990 |
| Grant date | Jun 30, 1992 |
| Priority date | — |
| Expiry date | May 23, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P15/0888
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A micromechanical accelerometer is disclosed comprising a mass of monocrystalline silicon in which a substantially symmetrical plate attached to a silicon frame by flexible linkages is produced by selective etching. The plate has a plurality of apertures patterned and etched therethrough to speed further etching and freeing of the plate and flexible linkages, suspending them above a void etched beneath. The plate has a weight disposed thereon near an end remote from the flexible linkages. The plate is capable of limited motion about an axis created by the flexible linkages. Stop means limit motion of the plate about the axis. Strain relief tension beams are provided to relieve stress induced by boron diffusion necessary to provide etch stopping and the tension beams are trimmable in a manner which permits tuning of the resonant frequency of the plate. Grooves or depressions are provided in the flexible linkages to resist bending or buckling without increasing torsional stiffness. The plate and flexible linkages are electrically isolated from the silicon mass and frame by dielectric or P-N junction isolation. Integral P-N junction electrodes and surface bridging electrodes may be us…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.