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:
Dec. 11, 1990
Filed:
Aug. 21, 1989
Douglas J Yoder, Sharpsville, IN (US);
Ronald E Brown, Kokomo, IN (US);
Paul E Stevenson, Kokomo, IN (US);
Donald L Hornback, Kokomo, IN (US);
Ronald K Leisure, Kokomo, IN (US);
Delco Electronics Corporation, Kokomo, IN (US);
Abstract
A monolithic pressure sensitive silicon integrated circuit is formed by first providing a localized etch-stop layer on one surface of the silicon chip, then growing successive epitaxial layers of opposite conductivity types over this surface. In the upper of the two layers, there is formed a bridge of four piezoresistors overlying the periphery of the etch-stop layer and the conditioning circuitry for amplifying the output of the bridge including both lateral and vertical junction transistors. The back surface of the chip is etched anisotropically to form a cavity that leaves a thin diaphragm underlying the bridge of the four piezoresistors.