Hermetically sealed ultra high temperature silicon carbide pressure transducers and method for fabricating same
US6058782A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 25, 1998 |
| Grant date | May 9, 2000 |
| Priority date | — |
| Expiry date | Sep 25, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L9/0042
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus and method for making ultra high temperature silicon carbide pressure transducers which prevents the deterioration of contact areas under harsh conditions, such as high temperatures and oxidizing atmospheres includes a first substrate of silicon carbide with a plurality of piezoresistive elements disposed on a central active region. A plurality of generally L-shaped contact areas extend from and substantially surround the central active region. On each contact area a metalized contact is formed. An isolation moat etched around the periphery of the first substrate separates each contact area from the other, and separates the contact areas from the periphery of the device. A second substrate of silicon carbide having a plurality of apertures extending therethrough which align with and correspond to a contact on each contact area is joined to the first substrate by electrostatic bonding or by employing a glass frit. The apertures are then filled with a glass metal frit mixture which includes platinum to provide a hermetic seal of the sensor element. A gold-plated pin or spherical contact is inserted into the glass metal frit filled apertures, and the entire structure is f…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.