US 11,894,214 B2
Detection and correction of system responses in real-time
Henning Stoschus, Wetzlar (DE); Stefan Eyring, Weilburg (DE); and Christopher Sears, Fremont, CA (US)
Assigned to KLA CORPORATION, Milpitas, CA (US)
Filed by KLA CORPORATION, Milpitas, CA (US)
Filed on Oct. 24, 2022, as Appl. No. 17/972,292.
Application 17/972,292 is a continuation of application No. 16/691,847, filed on Nov. 22, 2019, granted, now 11,508,551.
Claims priority of provisional application 62/785,164, filed on Dec. 26, 2018.
Claims priority of provisional application 62/781,412, filed on Dec. 18, 2018.
Claims priority of provisional application 62/779,485, filed on Dec. 14, 2018.
Prior Publication US 2023/0045072 A1, Feb. 9, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. H01J 37/22 (2006.01); H01J 37/28 (2006.01); H01J 37/304 (2006.01); G01N 23/2251 (2018.01); H01L 21/66 (2006.01); G06N 20/00 (2019.01)
CPC H01J 37/304 (2013.01) [G01N 23/2251 (2013.01); G06N 20/00 (2019.01); H01J 37/222 (2013.01); H01L 22/12 (2013.01); H01J 2237/221 (2013.01); H01J 2237/24475 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method, comprising:
emitting an electron beam towards a specimen;
modulating the electron beam to obtain a beam signal, wherein the modulating is based on a wave that controls the beam signal, and wherein the modulating includes adjusting a beam current that reaches the specimen;
detecting, using an electron detector, secondary and/or backscattered electrons emitted by the specimen to obtain electron data, wherein the electron data defines a detection signal;
determining, using a processor, a comparison between the wave controlling the beam signal and a wave for the detection signal; and
filtering, using the processor, the detection signal based on the comparison.