Sensor with at least one micromechanical structure, and method for producing it

US7273764B2 · kind B2 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Frank Reichenbach · Wannweil, DE
• Stefan Pinter · Reutlingen, DE
• Frank Henning · Reutlingen, DE
• Hans Artmann · Magstadt, DE
• Helmut Baumann · Gomaringen, DE
• Franz Laemer · Stuttgart, DE
• Michael Offenberg · Lörrach, DE
• Georg Bischopink · Neckartenzlingen, DE

Key dates

• Filing date: Jan 3, 2005
• Grant date: Sep 25, 2007
• Expiry date: Mar 6, 2025

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B81C2203/0145
• WIPO field: Micro-structural and nano-technology
• WIPO sector: Chemistry

Abstract

The invention relates to a sensor with at least one silicon-based micromechanical structure, which is integrated with a sensor chamber of a foundation wafer, and with at least one covering that covers the foundation wafer in the region of the sensor chamber, and to a method for producing a sensor. It is provided that in the sensor of the invention, the covering (13) comprises a first layer (32) (deposition layer) that is permeable to an etching medium and the reaction products, and a hermetically sealing second layer (34) (sealing layer) located above it, and that in the method of the invention, at least the sensor chamber (28) present in the foundation wafer (11) after the establishment of the structure (26) is filled with an oxide (30), in particular CVD oxide or porous oxide; the sensor chamber (28) is covered by a first layer (32) (deposition layer), in particular of polysilicon, that is transparent to an etching medium and the reaction products or is retroactively made transparent; the oxide (30) in the sensor chamber (28) is removed through the deposition layer (32) with the etching medium; and next, a second layer (34) (sealing layer), in particular of metal or an insulator,…