US 12,451,319 B2
Electron source with magnetic suppressor electrode
Nikolai Chubun, Palo Alto, CA (US); Xinrong Jiang, Palo Alto, CA (US); Youfei Jiang, Milpitas, CA (US); and Christopher Sears, Fremont, CA (US)
Assigned to KLA Corporation, Milpitas, CA (US)
Filed by KLA Corporation, Milpitas, CA (US)
Filed on Dec. 28, 2020, as Appl. No. 17/135,279.
Claims priority of provisional application 63/087,312, filed on Oct. 5, 2020.
Prior Publication US 2022/0108862 A1, Apr. 7, 2022
Int. Cl. H01J 37/063 (2006.01); H01J 37/09 (2006.01); H01J 37/14 (2006.01); H01J 37/32 (2006.01)
CPC H01J 37/063 (2013.01) [H01J 37/09 (2013.01); H01J 37/14 (2013.01); H01J 37/3255 (2013.01)] 12 Claims
OG exemplary drawing
 
1. An electron source, comprising:
an electron emitter configured to generate one or more electron beams;
a stand-alone magnetic suppressor electrode surrounding at least a portion of the electron emitter, wherein the magnetic suppressor electrode is formed from one or more magnetic materials, wherein the magnetic suppressor electrode includes a conical section that surrounds the electron emitter, wherein the magnetic suppressor electrode is configured to shield the shaft of the tip of electron emitter from the axial magnetic field from a magnetic lens thereby mitigating drift of the electron emitter; and
an extractor electrode positioned adjacent to a tip of the electron emitter.