Combined magnetometer accelerometer MEMS devices and methods
US10197590B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 17, 2015 |
| Grant date | Feb 5, 2019 |
| Priority date | — |
| Expiry date | May 10, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P2015/084
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Considerations for selecting capacitive sensors include accuracy, repeatability, long-term stability, ease of calibration, resistance to chemical and physical contaminants, size, packaging, integration options with other sensors and/or electronics, and cost effectiveness. It is beneficial if such sensors are amenable to above-IC integration with associated control/readout circuitry for reduced parasitics and reduced footprint through area sharing. The inventors have established a combined Lorentz force based magnetometer and accelerometer MEMS sensor exploiting a low temperature, above-IC-compatible fabrication process operating without requiring vacuum packaging. By switching an electrical current between two perpendicular directions on the device structure a 2D in-plane magnetic field measurement can be achieved while concurrently, the device serves as a 1D accelerometer for out-of-plane acceleration, by switching the current off and by monitoring the structure's capacitive change in response to acceleration. The design can thus separate magnetic and inertial force measurements, utilizing a single compact device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.