Tunable capacitor

US7821053B2 · kind B2 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Corey K. Barrows · Colchester, US
• Joseph A. Iadanza · South Burlington, US
• Edward J. Nowak · South Burlington, US
• Douglas W. Stout · Colchester, US
• Mark S. Styduhar · South Burlington, US

Key dates

• Filing date: Nov 15, 2006
• Grant date: Oct 26, 2010
• Expiry date: Nov 15, 2026

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D1/66

Abstract

Disclosed are embodiments of a transistor that operates as a capacitor and an associated method of tuning capacitance within such a capacitor. The embodiments of the capacitor comprise a field effect transistor with front and back gates above and below a semiconductor layer, respectively. The capacitance value exhibited by the capacitor can be selectively varied between two different values by changing the voltage condition in a source/drain region of the transistor, e.g., using a switch or resistor between the source/drain region and a voltage supply. Alternatively, the capacitance value exhibited by the capacitor can be selectively varied between multiple different values by changing voltage conditions in one or more of multiple channel regions that are flanked by multiple source/drain regions within the transistor. The capacitor will exhibit different capacitance values depending upon the conductivity in each of the channel regions.