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:
Jun. 18, 1996
Filed:
Nov. 22, 1994
Wen H Ko, Cleveland Hts., OH (US);
Case Western Reserve University, Cleveland, OH (US);
Abstract
A capacitive absolute pressure sensor. The sensor includes a substrate having an electrode deposited thereon and a diaphragm assembly disposed on the substrate. As pressure increases, the diaphragm deflects, touches the electrode (in the touch mode), and changes the capacitance of the sensor. The changed capacitance is sensed to thus sense pressure changes. A buried feedthrough is used to sense the change in a capacitance in a chamber under the diaphragm and thus determine the pressure sensed. A vacuum in the chamber is maintained by proper selection of a thickness of a sensing electrode and an insulating layer, exposition thereof to a thermal cycle, and the hermetic bonding of the diaphragm assembly to the substrate.