US 12,469,668 B2
Systems and methods for compensating dispersion of a beam separator in a single-beam or multi-beam apparatus
Weiming Ren, San Jose, CA (US); Xuedong Liu, San Jose, CA (US); Xuerang Hu, San Jose, CA (US); Xinan Luo, San Jose, CA (US); and Zhongwei Chen, San Jose, CA (US)
Assigned to ASML Netherlands B.V., Veldhoven (NL)
Filed by ASML Netherlands B.V., Veldhoven (NL)
Filed on May 9, 2022, as Appl. No. 17/662,453.
Application 17/662,453 is a continuation of application No. 16/047,987, filed on Jul. 27, 2018, granted, now 11,328,894.
Claims priority of provisional application 62/538,609, filed on Jul. 28, 2017.
Prior Publication US 2022/0262594 A1, Aug. 18, 2022
Int. Cl. H01J 37/153 (2006.01); H01J 37/05 (2006.01); H01J 37/14 (2006.01); H01J 37/147 (2006.01); H01J 37/24 (2006.01); H01J 37/244 (2006.01); H01J 37/28 (2006.01)
CPC H01J 37/153 (2013.01) [H01J 37/05 (2013.01); H01J 37/14 (2013.01); H01J 37/147 (2013.01); H01J 37/1472 (2013.01); H01J 37/244 (2013.01); H01J 37/28 (2013.01); H01J 2237/14 (2013.01); H01J 2237/151 (2013.01); H01J 2237/152 (2013.01); H01J 2237/1532 (2013.01); H01J 2237/1534 (2013.01); H01J 2237/2448 (2013.01); H01J 2237/2806 (2013.01)] 20 Claims
OG exemplary drawing
 
7. A charged particle beam apparatus comprising:
a source for generating a primary charged particle beam;
a first dispersion device below the source;
a beam separator below the first dispersion device;
an objective lens below the beam separator;
a sample stage for supporting a sample; and
a detector above the beam separator,
wherein the primary charged particle beam is focused by the objective lens onto the sample to form a primary probe spot thereon and generate a secondary charged particle beam therefrom,
wherein the beam separator is configured to separate the primary charged particle beam and the secondary charged particle beam so that the secondary charged particle beam is detected by the detector,
wherein the first dispersion device is configured to generate a first primary beam dispersion to the primary charged particle beam and the beam separator is configured to generate a second primary beam dispersion to the primary charged particle beam,
wherein the first dispersion device comprises a first electrostatic deflector and a first magnetic deflector, respectively configured to exert a first force and a second force on the primary charged particle beam, and wherein the first force and the second force are opposite to each other and form the first primary beam dispersion,
wherein the first primary beam dispersion is adjusted to make the first primary beam dispersion cancel an impact of the second primary beam dispersion on the primary probe spot, and an adjustment of the first primary beam dispersion causes an adjustment of a position of an object plane associated with the objective lens, the object plane being a virtual focal plane for a portion of charged particles of the primary charged particle beam, and
wherein a first deflection angle of the primary charged particle beam caused by the first dispersion device is unchanged when the first primary beam dispersion is changed with respect to the second primary beam dispersion.