Charged-particle-beam device, specimen-image acquisition method, and program recording medium

1. A charged-particle-beam device comprising:

a charged-particle optical lens tube that is subjected to vacuuming inside;

a specimen stage on which a specimen is mounted in a non-vacuum space;

a detector that detects secondary charged particles obtained by irradiation of the specimen with a primary charged-particle beam emitted from the charged-particle optical lens tube; and

a data processing unit that removes, from a detector signal, the effect that scattering of the primary charged-particle beam before the primary charged-particle beam reaches the specimen has on the spot shape of the primary charged-particle beam.

2. The charged-particle-beam device according to claim 1 , further comprising:

a barrier film that can hold differential pressure between a space which communicates with the inside of the charged-particle optical lens tube and which remains in a vacuum state, and the non-vacuum space in which the specimen is disposed, and that transmits or allows the primary charged-particle beam to pass,

wherein the data processing unit removes, from the detector signal, the effect that scattering of the primary charged-particle beam when the primary charged-particle beam passes through the barrier film has on the spot shape of the primary charged-particle beam.

3. The charged-particle-beam device according to claim 2 ,

wherein the data processing unit obtains the effect on the spot shape of the primary charged-particle beam, depending on a material type, density, and the thickness of the barrier film.

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

wherein the data processing unit removes, from the detector signal, the effect that scattering of the primary charged-particle beam due to a gas in the non-vacuum space has on the spot shape of the primary charged-particle beam.

5. The charged-particle-beam device according to claim 4 ,

wherein the data processing unit obtains the effect on the spot shape of the primary charged-particle beam, depending on the types of gas, a distance by which the primary charged-particle beam passes through the non-vacuum space, and pressure of the gas.

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

wherein a ratio of a length h1 of the charged-particle optical lens tube to a distance h2 by which the primary charged-particle beam passes through the non-vacuum space satisfies h1/h2≧1,000, in which h2 is equal to or less than 1 mm.

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

wherein the data processing unit generates a model of the spot shape of the primary charged-particle beam when the primary charged-particle beam reaches the specimen, using a spot shape of a non-scattered charged-particle beam of the primary charged-particle beams, which is not scattered before reaching the specimen, and a spot shape of scattered charged-particle beam of the primary charged-particle beams, which is scattered before reaching the specimen.

8. The charged-particle-beam device according to claim 7 ,

wherein a width (d1) of the spot shape of the non-scattered charged-particle beam is 1 nm to 100 nm,

wherein a width (d2) of the spot shape of the scattered charged-particle beam is 10 nm to 10,000 nm, and

wherein a relationship between the width d1 and the width d2 satisfies d2/d1≧10.

9. The charged-particle-beam device according to claim 1 , further comprising:

a display that displays an operation screen on which a user can designate a region as an image restoration processing target on an image formed based on a signal from the detector.

10. The charged-particle-beam device according to claim 1 , further comprising:

a display that displays an operation screen on which a user can designate a first region on which image restoration processing is performed using a first parameter set, and a second region on which image restoration processing is performed using a second parameter different from the first parameter set on an image formed based on a signal from the detector.

11. A specimen-image acquisition method comprising:

emitting a primary charged-particle beam from a charged-particle optical lens tube that is subjected to vacuuming inside;

irradiating, with the primary charged-particle beam, a specimen mounted in a non-vacuum space;

detecting secondary charged particles obtained by irradiation of the specimen with the primary charged-particle beam; and

removing, from a detector signal, the effect that scattering of the primary charged-particle beam before the primary charged-particle beam reaches the specimen has on the spot shape of the primary charged-particle beam.

12. The specimen-image acquisition method according to claim 11 , further comprising:

causing the primary charged-particle beam emitted from the charged-particle optical lens tube to be transmitted through or to pass through a barrier film which can hold differential pressure between a space that communicates with the inside of the charged-particle optical lens tube and that remains in a vacuum state, and the non-vacuum space in which the specimen is disposed; and

removing, from the detector signal, the effect that scattering of the primary charged-particle beam when the primary charged-particle beam passes through the barrier film has on the spot shape of the primary charged-particle beam.

13. The specimen-image acquisition method according to claim 12 , further comprising:

obtaining the effect on the spot shape of the primary charged-particle beam, depending on a material type, density, and the thickness of the barrier film.

14. The specimen-image acquisition method according to claim 11 , further comprising:

removing, from the detector signal, the effect that scattering of the primary charged-particle beam due to a gas in the non-vacuum space has on the spot shape of the primary charged-particle beam.

15. The specimen-image acquisition method according to claim 14 , further comprising:

obtaining the effect on the spot shape of the primary charged-particle beam, depending on the types of gas, a distance by which the primary charged-particle beam passes through the non-vacuum space, and pressure of the gas.

16. The specimen-image acquisition method according to claim 11 , further comprising:

generating a model of the spot shape of the primary charged-particle beam when the primary charged-particle beam reaches the specimen, using a spot shape of a non-scattered charged-particle beam of the primary charged-particle beams, which is not scattered before reaching the specimen, and a spot shape of scattered charged-particle beam of the primary charged-particle beams, which is scattered before reaching the specimen; and

obtaining the effect on the spot shape of the primary charged-particle beam using the model.

17. The specimen-image acquisition method according to claim 16 ,

wherein a width (d1) of the spot shape of the non-scattered charged-particle beam is 1 nm to 100 nm,

wherein a width (d2) of the spot shape of the scattered charged-particle beam is 10 nm to 10,000 nm, and

wherein a relationship between the width d1 and the width d2 satisfies d2/d1≧10.

18. The specimen-image acquisition method according to claim 11 , further comprising:

performing image restoration processing on a part of region, which is designated by a user, on an image formed based on a signal from the detector.

19. The specimen-image acquisition method according to claim 11 ,

wherein a user can designate a first region on which image restoration processing is performed using a first parameter set, and a second region on which image restoration processing is performed using a second parameter different from the first parameter set on an image formed based on a signal from the detector.

20. A program recording medium that stores a program executed by a computer connected to a charged-particle-beam device including

a charged-particle optical lens tube that is subjected to vacuuming inside,

a specimen stage on which a specimen is mounted in a non-vacuum space, and

a detector that detects secondary charged particles obtained by irradiation of the specimen with a primary charged-particle beam emitted from the charged-particle optical lens tube,

wherein the program performs a process of removing, from a detector signal, the effect that scattering of the primary charged-particle beam before the primary charged-particle beam reaches the specimen has on the spot shape of the primary charged-particle beam.