Charged particle beam device and phase plate

1. A charged particle beam device comprising:

a first charged particle source that generates first charged particles and irradiates a sample with the generated first charged particles;

a phase plate that changes phases of the first charged particles in accordance with charged states of portions through which the first charged particles are transmitted; and

a phase plate control system that controls the charging of the phase plate,

wherein the phase plate control system includes at least one of a second charged particle source generating second charged particles or a photon source generating a photon flux, and

the phase plate control system controls the charging of the phase plate with irradiation of at least one of the second charged particles or the photon flux.

2. The charged particle beam device according to claim 1 , wherein

the phase plate includes a first area and a second area having mutually-different charging rates and causes a phase difference between the first charged particles passing through the first area and the first charged particles passing through the second area.

3. The charged particle beam device according to claim 1 ,

wherein energy of the second charged particles and the photon flux is lower than energy of the first charged particles irradiated from the first charged particle source.

4. The charged particle beam device according to claim 1 , wherein

the phase plate control system includes a photon source generating UV light and controls the charging of the phase plate with irradiation of the UV light.

5. The charged particle beam device according to claim 1 , wherein

a thickness of a portion of the phase plate through which the first charged particles that are not scattered pass and a thickness of a portion through which the first charged particles that are scattered pass are different from each other.

6. The charged particle beam device according to claim 1 , wherein

the phase plate is disposed on a back focal plane, at an irradiation diaphragm position, or at an equivalent position thereof.

7. The charged particle beam device according to claim 1 , wherein

the phase plate control system includes at least one of a drift tube guiding second charged particles to the phase plate or a light guide tube guiding a photon flux to the phase plate.

8. The charged particle beam device according to claim 1 , wherein

the phase plate control system is a vacuum electric field emission electron emitter that is mounted on a rear face side of a sample holder holding the sample.

9. The charged particle beam device according to claim 1 , wherein

the phase plate control system is disposed on a downstream side of an objective lens.

10. A phase plate comprising:

a phase plate that changes phases of first charged particles to be irradiated to a sample from a charged particle source in accordance with charged states of portions through which the first charged particles are transmitted;

a member of an incomplete conductor; and

a second member, wherein the second member is one of a conduction member or a photoconductive member.

11. The phase plate according to claim 10 , comprising:

a first area and a second area having mutually-different charging rates.

12. The phase plate according to claim 11 ,

wherein the second member is the conduction member, and the first area is formed with the member of the incomplete conductor surrounded by the conduction member, and the second area is formed with a member surrounding the periphery of the first area with the conduction member interposed therebetween.

13. The phase plate according to claim 10 , comprising:

wherein the second member is the conduction member, and the member of the incomplete conductor is surrounded by the conduction member.

14. The phase plate according to claim 10 :

wherein the second member is the photoconductive member, and the member of the incomplete conductor connected to a support member through the photoconductive member.

15. The phase plate according to claim 10 :

wherein the second member is the conduction member, and at least a part of the member of the incomplete conductor is coated with the photoconductive member.

16. A phase plate, comprising:

a phase plate that changes phases of first charged particles to be irradiated to a sample from a charged particle source in accordance with charged states of portions through which the first charged particles are transmitted;

a substrate formed of a first material;

an island part formed in a part of the substrate using a second material different from the first material; and

a conduction layer covering surfaces of the substrate and the island part.