US 12,394,585 B2
Electron source, electron gun, and charged particle beam device
Keigo Kasuya, Tokyo (JP); Shuhei Ishikawa, Tokyo (JP); Kenji Tanimoto, Tokyo (JP); Takashi Doi, Tokyo (JP); Soichiro Matsunaga, Tokyo (JP); Hiroshi Morita, Tokyo (JP); Daigo Komesu, Tokyo (JP); and Kenji Miyata, Tokyo (JP)
Assigned to HITACHI HIGH-TECH CORPORATION, Tokyo (JP)
Appl. No. 17/928,401
Filed by Hitachi High-Tech Corporation, Tokyo (JP)
PCT Filed Jun. 29, 2020, PCT No. PCT/JP2020/025496
§ 371(c)(1), (2) Date Nov. 29, 2022,
PCT Pub. No. WO2022/003770, PCT Pub. Date Jan. 6, 2022.
Prior Publication US 2023/0352262 A1, Nov. 2, 2023
Int. Cl. H01J 37/065 (2006.01); H01J 37/073 (2006.01); H01J 37/28 (2006.01)
CPC H01J 37/065 (2013.01) [H01J 37/073 (2013.01); H01J 37/28 (2013.01)] 17 Claims
OG exemplary drawing
 
1. An electron source comprising:
a suppressor electrode having an opening at one end portion thereof in a direction along a central axis; and
an electron emission material having a distal end protruding from the opening, wherein
the suppressor electrode further includes a receding portion receding to a position farther from the distal end of the electron emission material than the end portion of the suppressor electrode in the direction along the central axis at a position in an outer peripheral direction than the opening, and
at least a part of the receding portion is disposed within a diameter of 2810 μm from a center of the opening.