The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 21, 2002
Filed:
Feb. 12, 2001
Robert Aigner, München, DE;
Hans-Jörg Timme, Ottobrunn, DE;
Thomas Bever, München, DE;
Infineon Technologies AG, Munich, DE;
Abstract
The invention relates to a micromechanical sensor and to a corresponding production method that includes the following steps: a) preparing a doped semiconductor wafer; b) applying an epitaxial layer that is doped in such a way that a jump in the charge carrier density in the interface between the semiconductor wafer and the epitaxial layer occurs; c) optionally etching ventilation holes traversing the epitaxial layer and optionally filling the ventilation holes with a sacrificial material; d) depositing at least one sacrificial layer, at least one spacing layer, a membrane and optionally a semiconductor circuit on the top side of the epitaxial layer using a technology known per se, wherein the semiconductor circuit may be applied after the membrane is formed or while depositing the layers required to form the membrane; e) etching a hole on the back part of the sensor, wherein the etching method is selected in such a way that etching advances in the direction of the top side and ceases in the interference between the wafer and the epitaxial layer by changing charge carrier concentration. The invention also relates to the utilization of the micromechanical sensor in pressure sensors or microphones.