US 11,749,497 B2
Charged particle beam apparatus
Shunsuke Mizutani, Tokyo (JP); Shahedul Hoque, Tokyo (JP); Uki Ikeda, Tokyo (JP); and Makoto Suzuki, Tokyo (JP)
Assigned to Hitachi High-Tech Corporation, Tokyo (JP)
Filed by Hitachi High-Tech Corporation, Tokyo (JP)
Filed on Aug. 5, 2021, as Appl. No. 17/394,925.
Application 17/394,925 is a division of application No. 16/482,765, granted, now 11,139,144, previously published as PCT/JP2017/011908, filed on Mar. 24, 2017.
Prior Publication US 2021/0375583 A1, Dec. 2, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. H01J 37/28 (2006.01); H01J 37/147 (2006.01); H01J 37/244 (2006.01)
CPC H01J 37/28 (2013.01) [H01J 37/1474 (2013.01); H01J 37/244 (2013.01); H01J 2237/2443 (2013.01); H01J 2237/24475 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A charged particle beam apparatus, comprising:
an objective lens that is configured to converge charged particle beams emitted from a charged particle source; and
a detector that is configured to detect backscattered electrons emitted from a sample, wherein
the objective lens includes an inner magnetic path and an outer magnetic path that are formed so as to enclose a coil, the inner magnetic path includes a first inner magnetic path that is disposed at a position opposite to an optical axis of the charged particle beams, and a second inner magnetic path that is formed at a slant with respect to the optical axis of the charged particle beams and includes a leading end of the inner magnetic path,
the detector includes a detection surface that detects the backscattered electrons, and a conversion element that converts light obtained by the detection of the backscattered electrons on the detection surface into an electric signal, and
the detection surface and the conversion element are disposed at a space between the first inner magnetic path and a virtual straight line that passes through the leading end of the inner magnetic path and is parallel to the optical axis of the charged particle beams, the space being located to between the sample and an upper end of the first inner magnetic path.