| US 11,810,753 B2 | ||
| Methods of determining aberrations of a charged particle beam, and charged particle beam system | ||
| Dominik Ehberger, Ebersberg (DE); John Breuer, Munich (DE); and Matthias Firnkes, Walpertskirchen (DE) | ||
| Assigned to ICT Integrated Circuit Testing Gesellschaft für Halbleiterprüftechnik mbH, Heimstetten (DE) | ||
| Filed by ICT Integrated Circuit Testing Gesellschaft für Halbleiterprüftechnik mbH, Heimstetten (DE) | ||
| Filed on Oct. 13, 2021, as Appl. No. 17/500,842. | ||
| Prior Publication US 2023/0113857 A1, Apr. 13, 2023 | ||
| Int. Cl. H01J 37/244 (2006.01); H01J 37/22 (2006.01); H01J 37/153 (2006.01); G06T 7/00 (2017.01); H01J 37/10 (2006.01) | ||
| CPC H01J 37/244 (2013.01) [G06T 7/0002 (2013.01); H01J 37/153 (2013.01); H01J 37/222 (2013.01); G06T 2207/10061 (2013.01); G06T 2207/10148 (2013.01); H01J 37/10 (2013.01); H01J 2237/24578 (2013.01)] | 21 Claims |
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1. A method of determining aberrations of a charged particle beam focused by a focusing lens toward a sample in a charged particle beam system, comprising:
(a) taking one or more images of the sample at one or more defocus settings to provide one or more taken images; (b) simulating one or more images of the sample taken at the one or more defocus settings based on a set of beam aberration coefficients (iC) and a focus image of the sample, to provide one or more simulated images; (c) comparing the one or more taken images and the one or more simulated images for determining a magnitude (R) of a difference therebetween; and (d) varying the set of beam aberration coefficients (iC) to provide an updated set of beam aberration coefficients (i+1C) and repeating (b) and (c) using the updated set of beam aberration coefficients (i+1C) in an iterative process for minimizing said magnitude (R). |