Pressure sensor and method for the manufacture thereof

US5005421A · kind A · utility

Assignee

• Endress u Hauser GmbH u Co. · DE

Inventors

• Frank Hegner · Bad Kötzting, DE
• Gerhard Dittrich · Lörrach, DE
• Thomas Klahn · Glückstadt, DE

Key dates

• Filing date: Jul 18, 1989
• Grant date: Apr 9, 1991
• Expiry date: Jul 18, 2009

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T29/43
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The pressure sensor comprises a base body and diaphragm which are assembled at a defined distance apart parallel to each other to form a chamber, at least one of the two assembled parts consisting of ceramic, glass, metal or a monocrystalline material. In dependence upon the external pressure acting on the pressure sensor the distance between said parts and thus the capacitance between two electrodes carried by said parts changes. The base body and the diaphragm are firmly connected together by a shaped part of metal serving at the same time as spacer. If at least one of the two parts consists of ceramic, glass, metal or a monocrystalline material, the two joined parts can be soldered together by a shaped part of active solder. If the two assembled parts consist of oxide ceramic or sapphire they can be connected together by the direct copper bonding method. In this case the shaped part consists of copper which is connected to the two parts by a eutectic melt forming at the surface.