Charged particle beam device
Provided is a charged particle beam device in which a support body is rigid enough to support a sample chamber while the vibration of the support body is reduced even under the action of a disturbance such as environmental sound, the degree of parallelism of the support body is maintained, and increase in weight of the support body is suppressed. The support body includes: a first member which supports a mounted object, and is supported by a vibration removing mount; second members which have a thickness different from that of the first member and arranged to overlap the first member; fixing members which fix the first member and the second members; and damping members which have rigidity lower than the fixing members and are deformed by a difference in variations between the first member and the second members.
1. A charged particle beam device, comprising:
a mounted object which includes a column, a sample chamber, and a stage;
a support body which supports the mounted object; and
a vibration removing mount which supports the support body,
wherein the support body includes:
a load plate which supports the mounted object, and is supported by the vibration removing mount;
a damping plate which has a thickness different from that of the load plate and is arranged to overlap the load plate;
a fixing structure which fixes the load plate and the damping plate; and
a damping structure which has rigidity lower than the fixing structure and is deformed by a difference in variation between the load plate and the damping plate;
wherein the fixing structure is arranged at a position corresponding to a node position of the load plate in an eigenmode, and
wherein the damping structure is arranged at a position corresponding to an antinode position of the load plate in the eigenmode.
2. The charged particle beam device according to claim 1 ,
wherein the fixing structure is arranged at a position corresponding to a node position of a plate of the load plate in a bending mode, and
wherein the damping structure is arranged at a position corresponding to an antinode position of the plate of the load plate in the bending mode.
3. The charged particle beam device according to claim 2 ,
wherein the load plate has a rectangular plate shape,
wherein the fixing structure is arranged at a position corresponding to a node position of the plate of the load plate in which four corners thereof vibrate in the bending mode, and
wherein the damping structure is arranged at a position corresponding to an antinode position of the plate of the load plate in which the four corners vibrate in the bending mode.
4. The charged particle beam device according to claim 1 ,
wherein the load plate has a square plate shape,
wherein the fixing structure is arranged in a range of 1/7 or more and ⅙ or less of a length of a side of the load plate from an end of the load plate, and
wherein the damping structure is arranged in a range of ⅕ or more and ¼ or less of a length of a side of the load plate from an end of the load plate.
5. The charged particle beam device according to claim 1 ,
wherein the load plate is a plate structure in which a plate thickness is 20 mm or more and 50 mm or less, and
wherein the damping plate is a plate structure in which a plate thickness is ⅓ or more and ⅔ or less of the plate thickness of the load plate.
6. The charged particle beam device according to claim 1 ,
wherein the load plate is divided into a plurality of portions.
7. The charged particle beam device according to claim 1 ,
wherein the damping structure is arranged on outer peripheral side surfaces of the load plate and the damping plate.
8. The charged particle beam device according to claim 1 ,
wherein the damping structure is arranged in a stepped groove provided in the load plate or the damping plate.