US 11,929,232 B2
Systems and methods for charged particle flooding to enhance voltage contrast defect signal
Frank Nan Zhang, San Jose, CA (US); Zhongwei Chen, San Jose, CA (US); Yixiang Wang, Fremont, CA (US); and Ying Crystal Shen, Fremont, CA (US)
Assigned to ASML Netherlands B.V., Veldhoven (NL)
Filed by ASML Netherlands B.V., Veldhoven (NL)
Filed on Sep. 18, 2020, as Appl. No. 17/026,044.
Application 17/026,044 is a continuation of application No. 16/053,636, filed on Aug. 2, 2018, granted, now 10,784,077.
Claims priority of provisional application 62/550,613, filed on Aug. 26, 2017.
Claims priority of provisional application 62/540,548, filed on Aug. 2, 2017.
Prior Publication US 2021/0142979 A1, May 13, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. H01J 37/26 (2006.01); H01J 37/04 (2006.01); H01J 37/28 (2006.01)
CPC H01J 37/265 (2013.01) [H01J 37/045 (2013.01); H01J 37/266 (2013.01); H01J 37/28 (2013.01); H01J 2237/0044 (2013.01); H01J 2237/0048 (2013.01); H01J 2237/0453 (2013.01); H01J 2237/0455 (2013.01); H01J 2237/0458 (2013.01); H01J 2237/049 (2013.01); H01J 2237/28 (2013.01); H01J 2237/2817 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A charged particle beam system comprising:
an adjustable gun aperture configured to provide different aperture sizes and allow a charged particle beam to pass therethrough;
an adjustable column aperture configured to provide different aperture sizes and allow the charged particle beam to pass therethrough; and
a controller configured to cause the charged particle beam system to perform operations comprising:
adjusting the adjustable gun aperture to a first aperture size configured to pass the charged particle beam at a first current level;
controlling the charged particle beam system in a first mode to defocus the charged particle beam and flood a region of a sample with charged particles of the charged particle beam, wherein the charged particle beam is incident on the sample at the first current level:
after flooding the region of the sample, adjusting the adjustable gun aperture to a second aperture size configured to pass the charged particle beam at a second current level, wherein the first current level is greater than the second current level;
adjusting the adjustable column aperture to a third aperture size configured to pass the charged particle beam at a third current level, wherein the second current level is greater than the third current level;
controlling the charged particle beam system in a second mode to focus the charged particle beam to a part of the region of the sample to inspect the part of the region of the sample, wherein the charged particle beam is incident on the sample at the third current level; and
moving the sample and repeating the operations above to inspect other regions of the sample.