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:
Nov. 23, 1999
Filed:
Mar. 20, 1998
Takamasa Yoshikawa, Tsurugashima, JP;
Kiyohide Ogasawara, Tsurugashima, JP;
Hiroshi Ito, Tsurugashima, JP;
Masataka Yamaguchi, Tsurugashima, JP;
Shingo Iwasaki, Tsurugashima, JP;
Nobuyasu Negishi, Tsurugashima, JP;
Takashi Chuman, Tsurugashima, JP;
Pioneer Electronic Corporation, Tokyo, JP;
Abstract
An electron emission device includes: a semiconductor layer; a porous semiconductor; and a thin-film metal electrode which are layered in turn. The electrode faces a vacuum space. The porous semiconductor layer has at least two or more of porosity-changed layers which have porosities which are different from each other in the thickness direction. The electron emission device emits electrons when an electric field is applied between the semiconductor layer and the thin-film metal electrode. An insulator layer made of a material selected from silicon oxide or silicon nitride may be formed between the porous semiconductor layer and the thin-film metal electrode. Si skeletons of the porous semiconductor layer are oxidized or nitrided.