公开(公告)号：US11322329B2

公开(公告)日：2022-05-03

申请号：US17260612

申请日：2018-08-27

Applicant: HITACHI HIGH-TECH CORPORATION

Inventor： Toshiaki Kusunoki ,  Tomihiro Hashizume ,  Keigo Kasuya ,  Noriaki Arai ,  Hiromitsu Seino ,  Minoru Kaneda ,  Takashi Ohshima ,  Soichiro Matsunaga

IPC: H01J37/065 ,  H01J37/10 ,  H01J37/147 ,  H01J37/244 ,  H01J37/28

Abstract: The invention provides an electron source including a columnar chip of a hexaboride single crystal, a metal pipe that holds the columnar chip of the hexaboride single crystal, and a filament connected to the metal pipe at a central portion. The columnar chip of the hexaboride single crystal is formed into a cone shape at a portion closer to a tip than a portion held in the metal pipe, and a tip end portion having the cone shape has a (310) crystal face. Schottky electrons are emitted from the (310) crystal face. According to the invention, it is possible to provide a novel electron source having monochromaticity, long-term stability of an emitter current, and high current density.