Method for manufacturing a micromechanical sensor element

US7572661B2 · kind B2 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Hubert Benzel · Neckartenzlingen, DE
• Stefan Finkbeiner · Gomaringen, DE
• Matthias Illing · Tübingen, DE
• Frank Schaefer · Lörrach, DE
• Simon Armbruster · Wannweil, DE
• Gerhard Lammel · Lörrach, DE
• Christoph Schelling · Stuttgart, DE
• Joerg Brasas · Neckartenzlingen, DE

Key dates

• Filing date: Sep 8, 2005
• Grant date: Aug 11, 2009
• Expiry date: Sep 12, 2026

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B81C2201/0116
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Described is a method for manufacturing a micromechanical sensor element and a micromechanical sensor element manufactured in particular using such a method which has a hollow space or a cavity and a membrane for detecting a physical variable. Different method steps are performed for manufacturing the sensor element, among other things, a structured etch mask having a plurality of holes or apertures being applied on a semiconductor substrate. Moreover, an etch process is used to create depressions in the semiconductor substrate beneath the holes in the structured etch mask. Anodization of the semiconductor material is subsequently carried out, the anodization taking place preferably starting from the created depressions in the semiconductor substrate. Due to this process, porous areas are created beneath the depressions, a lattice-like structure made of untreated, i.e., non-anodized, substrate material remaining between the porous areas and the depressions. This lattice-like structure extends preferably from the surface of the semiconductor into the depth. The etch mask for creating the depressions may be removed, optionally prior to or subsequent to the anodization. A temperature …