MEMS vacuum sensor based on the friction principle

US8186225B2 · kind B2 · utility

Assignees

• Fraunhofer-Gesellschaft zur förderung der angewandten Forschung e.V. · DE
• Technische Universität Chemnitz · DE

Inventors

• Steffen Kurth · Bitterfeld-Wolfen, DE
• Dirk Tenholte · Chemnitz, DE
• Karla Hiller · Oelsnitz, DE
• Christian Kaufmann · Sindelfingen, DE
• Thomas Gessner · Plymouth, US
• Wolfram Doetzel · Chemnitz, DE

Key dates

• Filing date: May 9, 2007
• Grant date: May 29, 2012
• Expiry date: Nov 12, 2028

Classification

• Technology area (CPC G): Physics
• CPC primary: G01L21/22
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The invention relates to a sensor element for pressure measurement, having a substrate (5) and at least one mass element (1), which is arranged spaced apart from the substrate (5) and is connected in an oscillating manner to the substrate (5) and/or a support body (6) fixed relative to the substrate (5), so that a gap is formed between the mass element (1) and the substrate (5), the width of which can be varied through oscillations of the mass element (1). At least one recess and/or at least one bushing (4) is located in the surface of the substrate (5) delimiting the gap, which recess is used for reducing the damping of the oscillation of the mass element through the gas or plasma surrounding the mass element (1). The sensor element is used in particular in pressure sensors for measuring pressures in the vacuum range. Through the use of the sensor element according to the invention as a pressure sensor, maximum pressures up to the range of atmospheric air pressure can be recorded. The lowest pressures to be determined are in the range of 10−6 mbar.