US 12,334,298 B2
Charged particle gun, charged particle beam system, and lock nut
Teruaki Hasegawa, Tokyo (JP)
Assigned to Hitachi High-Tech Corporation, Tokyo (JP)
Appl. No. 17/913,450
Filed by Hitachi High-Tech Corporation, Tokyo (JP)
PCT Filed Apr. 7, 2020, PCT No. PCT/JP2020/015619
§ 371(c)(1), (2) Date Sep. 22, 2022,
PCT Pub. No. WO2021/205526, PCT Pub. Date Oct. 14, 2021.
Prior Publication US 2023/0126658 A1, Apr. 27, 2023
Int. Cl. H01J 37/20 (2006.01); H01J 37/295 (2006.01)
CPC H01J 37/20 (2013.01) [H01J 37/2955 (2013.01); H01J 2237/2007 (2013.01); H01J 2237/20207 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A charged particle gun comprising:
a charged particle source;
a bolt having the charged particle source attached thereto;
a nut including a first surface and a second surface on an opposite side of the first surface and configured to hold the charged particle source by being screwed onto the bolt having the charged particle source attached thereto; and
a nut seat surface configured to contact the second surface of the nut,
wherein the nut includes:
the first surface, the second surface, an outer surface, and an inner surface;
a screw thread section provided on a portion of the inner surface and formed with a plurality of screw threads to be screwed with the bolt;
an inclination adjustment section configured to be able to adjust an inclination angle of the charged particle source with respect to the nut seat surface, the charged particle source being in a state of being held by the nut; and
a lock section configured to prevent loosening of a screwed state between the nut and the bolt, wherein:
the inner surface of the nut includes:
the screw thread section; and
a non-screw thread section having an inner diameter larger than an inner diameter of the screw thread section, and
the inclination adjustment section includes:
a first slit formed to be penetrated from a portion of the outer surface to a portion of the non-screw thread section;
an inclination adjustment screw;
a first portion positioned between the first slit and the second surface;
a second portion positioned between the first slit and the first surface; and
a first screw hole having the inclination adjustment screw screwed thereinto, the first screw hole being formed to be penetrated from the first surface to the first slit in the second portion,
wherein a tip of the inclination adjustment screw expands the first slit and presses the nut seat surface via the first portion, thereby changing the inclination angle of the charged particle source with respect to the nut seat surface.