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:
Feb. 26, 2002
Filed:
Nov. 29, 1999
Takeshi Uenoyama, Kyoto, JP;
Takao Tohda, Nara, JP;
Masahiro Deguchi, Osaka, JP;
Makoto Kitabatake, Nara, JP;
Kentaro Setsune, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
In an electron-emitting device, an electron supplying layer for supplying electrons is composed of an n-GaN layer. An electron transferring layer for moving electrons toward the surface is composed of non-doped (intrinsic) Al Ga N (0≦x≦1) having a graded composition for the Al concentration x. A surface layer is composed of non-doped AlN having a negative electron affinity (NEA). The electron transferring layer composed of Al Ga N has a band gap which is enlarged nearly continuously from the electron supplying layer to the surface layer and a negative electron affinity or a positive electron affinity close to zero. If such a voltage V as to render the surface electrode side positive is applied, the band of Al Ga N is bent, whereby a current derived mainly from a diffused current flows from the electron supplying layer to the surface layer through the electron transferring layer. Thereby excellent electron emitting characteristic is obtained.