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:
Apr. 02, 2002
Filed:
May. 26, 1999
Heribert Weber, Nuertingen, DE;
Steffen Schmidt, Reutlingen, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
A process for producing a sensor membrane substrate, in particular, for a mass flow sensor or a pressure sensor, the substrate having on its front a membrane, which is fixed at the edge of an opening that is etched free from the back. The process includes the following steps: providing a substrate; local thickening the substrate in an area on the front opposite the edge, the thickened portion having a continuous transition to the substrate; depositing a membrane layer on the front having the locally oxidized area; and etching free the opening from the back to clear the membrane in such a way that the edge is located underneath the thickened area.