Pressure sensor including a diaphragm having a protective layer thereon

US5076147A · kind A · utility

Assignee

• Endress u Hauser GmbH u Co. · DE

Inventors

• Frank Hegner · Bad Kötzting, DE
• Manfred Frank · Auckland, NZ

Key dates

• Filing date: Mar 26, 1990
• Grant date: Dec 31, 1991
• Expiry date: Mar 26, 2010

Classification

• Technology area (CPC G): Physics
• CPC primary: G01L19/0627
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The pressure sensor consists of a substrate and a diaphragm joined together around the periphery so as to form a chamber. The surface of the diaphragm facing away from the substrate is exposed to a medium whose pressure is to be measured. To protect the diaphragm against corrosion or abrasion, the diaphragm surface exposed to the medium is covered with a layer of silicon carbide, preferably by chemical vapor deposition.