US 12,339,241 B2
Multiple secondary electron beam alignment method, multiple secondary electron beam alignment apparatus, and electron beam inspection apparatus
Koichi Ishii, Kawasaki (JP); and Atsushi Ando, Edogawa-ku (JP)
Assigned to NuFlare Technology, Inc., Yokohama (JP)
Filed by NuFlare Technology, Inc., Yokohama (JP)
Filed on Apr. 8, 2022, as Appl. No. 17/658,557.
Claims priority of application No. 2021-080643 (JP), filed on May 11, 2021; and application No. 2022-002324 (JP), filed on Jan. 11, 2022.
Prior Publication US 2022/0365010 A1, Nov. 17, 2022
Int. Cl. G01N 23/225 (2018.01)
CPC G01N 23/225 (2013.01) [G01N 2223/07 (2013.01); G01N 2223/3303 (2013.01); G01N 2223/646 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A multiple secondary electron beam alignment method comprising:
scanning a plurality of first detection elements of a multi-detector, which are arrayed in a grid, with multiple secondary electron beams emitted from a surface of a target object on a stage;
detecting a plurality of beams including a corner beam located at a corner in the multiple secondary electron beams by each of a plurality of second detection elements in the plurality of first detection elements;
calculating a positional relationship between the plurality of beams including the corner beam and the plurality of second detection elements, which have detected the plurality of beams including the corner beam, in the plurality of first detection elements;
calculating, based on the positional relationship, a shift amount for aligning the plurality of first detection elements with the multiple secondary electron beams; and
moving, using the shift amount, the multi-detector relatively to the multiple secondary electron beams.