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. 22, 1992
Filed:
Oct. 15, 1991
Kenneth D Cornett, Albuquerque, NM (US);
E S Ramakrishnan, Albuquerque, NM (US);
Gary H Shapiro, Albuquerque, NM (US);
Raymond M Caldwell, Albuquerque, NM (US);
Wei-Yean Howng, Albuquerque, NM (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A voltage variable capacitor (10) has as the base substrate a silicon wafer with a layer of high resistivity semiconductor material on top of the substrate. An insulating layer (16) of a metal oxide having a dielectric constant greater than the dielectric constant of the semiconductors (12), such as zirconium titanate, is formed on top of the high resistivity layer, and a metal electrode (18) is formed on the insulating layer (16). When the electrode is energized, a depletion layer (20) is formed in the high resistivity layer. By varying the voltage applied to the electrode, the capacitance of the device is altered.