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:
Sep. 16, 2008
Filed:
May. 22, 2007
Nobuaki Teraguchi, Nara, JP;
Nobuaki Teraguchi, Nara, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A field-effect transistor is provided which includes: a first nitride semiconductor layer having a lattice constant aand a bandgap Eg; a second nitride semiconductor layer stacked on the first nitride semiconductor layer and having a lattice constant aand a bandgap Eg; a source electrode and a drain electrode formed on the second nitride semiconductor layer; a piezo-effect film formed on the second nitride semiconductor layer in a region between the source electrode and the drain electrode; and a gate electrode formed on a region of the piezo-effect film. The relation between the lattice constants aand ais a>a. The relation between the bandgaps Egand Egis Eg<Eg. The residual polarization density at that surface of the piezo-effect film which faces the second nitride semiconductor layer is equal to or higher than the density of electric charges of a two-dimensional electron gas layer at an interface between the first nitride semiconductor layer and the second nitride semiconductor layer, and negative charges are polarized at that surface of the piezo-effect film which faces the second nitride semiconductor layer.