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. 16, 2003
Filed:
Oct. 09, 2002
Stanley J. Klodzinski, Bend, OR (US);
Advanced Power Technology, Inc., Bend, OR (US);
Abstract
A power MOSFET type device, which can include an IGBT or other VDMOS device having similar forward transfer characteristics, is formed with an asymmetrical channel, to produce different gate threshold voltage characteristics in different parts of the device. The different gate threshold voltage characteristics can be achieved either by different source region doping concentrations or different body region doping concentrations subjacent the gate oxide, or by asymmetrical gate oxide thicknesses. The portion of overall channel affected can be 50% or such other proportion as the designer chooses, to reduce the zero temperature coefficient point of the device and improve its Safe Operating Area in linear operation, while retaining low conduction loss. Multiple power MOSFET devices with asymmetrical channels can easily be used safely in parallel linear power amplifier circuits.