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:
Aug. 20, 2013
Filed:
Nov. 18, 2010
Lianjun Liu, Chandler, AZ (US);
Chad S. Dawson, Queen Creek, AZ (US);
Bernhard H. Grote, Phoenix, AZ (US);
Woo Tae Park, Singapore, SG;
Lianjun Liu, Chandler, AZ (US);
Chad S. Dawson, Queen Creek, AZ (US);
Bernhard H. Grote, Phoenix, AZ (US);
Woo Tae Park, Singapore, SG;
Freescale Semiconductor, Inc., Austin, TX (US);
Abstract
A pressure transducer includes a substrate, a piezoresistive element, a first conductive element, a first terminal, and a test structure. The substrate has a surface and a cavity. A diaphragm layer is formed over the cavity and over the surface of the substrate. The piezoresistive element is formed in the diaphragm layer. The first conductive element is formed in the diaphragm layer, and has a first conductivity type. The first conductive element is coupled to the piezoresistive element. The first terminal is formed over a surface of the diaphragm layer and coupled to the first conductive element. The test structure has the first conductivity type and is formed in the diaphragm layer. The test structure has an edge spaced apart from an edge of the first conductive element by a predetermined distance. A surface charge accumulation on the diaphragm layer is detected using the test structure.