Covered sealed pressure transducers and method for making same
US6229427A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 21, 1997 |
| Grant date | May 8, 2001 |
| Priority date | — |
| Expiry date | Jul 21, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L19/147
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for sealing a transducer of a type having a diaphragm with an active region and an inactive region, a stress sensing network associated with the active region of the diaphragm, contacts associated with the inactive region of the diaphragm, and lead-outs for coupling the stress sensing network to the contacts. The method comprises oxidizing the transducer to provide a first oxide layer which covers the diaphragm, the stress sensing network, the lead-outs and the contacts. Next, a layer of semiconductive material is deposited over the first oxide layer and is then planarized to provide a planar surface having a substantially flat and bondable surface. Finally, a cover member is bonded to the planar surface of the layer which covers the inactive region of the diaphragm to hermetically seal the stress sensing network and thereby provide a sealed transducer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.