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. 09, 2025
Filed:
Dec. 24, 2019
Hitachi High-tech Corporation, Tokyo, JP;
Toshiaki Kusunoki, Tokyo, JP;
Tomihiro Hashizume, Tokyo, JP;
Noriaki Arai, Tokyo, JP;
Keigo Kasuya, Tokyo, JP;
Hitachi High-Tech Corporation, Tokyo, JP;
Abstract
In a Schottky emitter or a thermal field emitter using a hexaboride single crystal, side emission from portions other than an electron emission portion is reduced. An electron source according to the invention includes: a protrusion () configured to emit an electron when an electric field is generated; a shank () that supports the protrusion () and has a diameter decreasing toward the protrusion (); and a body () that supports the shank (), in which the protrusion (), the shank (), and the body () are each made of a hexaboride single crystal, and a part including the shank () and the body () excluding the protrusion () is covered with a material having a work function higher than that of the hexaboride single crystal.