Micromachined magnetic field sensors
US8395381B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 9, 2010 |
| Grant date | Mar 12, 2013 |
| Priority date | — |
| Expiry date | Mar 14, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2224/73265
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A micromachined magnetic field sensor integrated with electronics is disclosed. The magnetic field sensors utilize Hall-effect sensing mechanisms to achieve 3-axis sensing. A Z axis sensor can be fabricated either on a device layer or on a conventional IC substrate with the design of conventional horizontal Hall plates. An X and Y axis sensor are constructed on the device layer. In some embodiments, a magnetic flux concentrator is applied to enhance the performance of the magnetic field sensor. In some embodiments, the magnetic field sensors are placed on slope sidewalls to achieve 3-axis magnetic sensing system. In some embodiments, a stress isolation structure is incorporated to lower the sensor offset. The conventional IC substrate and device layer are connected electrically to form a 3-axis magnetic sensing system. The magnetic field sensor can also be integrated with motion sensors that are constructed in the similar technology.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.