Charged-Particle-Beam Device, Specimen-Image Acquisition Method, and Program Recording Medium

Patent metadata

Field	Value
Publication number	US-2016336145-A1
Application number	US-201415110284-A
Country	US
Kind code	A1
Filing date	Dec 3, 2014
Priority date	Jan 27, 2014
Publication date	Nov 17, 2016
Grant date	—

Abstract

A charged-particle-beam device is provided with a data processing unit that removes, from a detector signal, the effect that scattering of a primary charged-particle beam before the primary charged-particle beam reaches a specimen has on the spot shape of the primary charged-particle beam. For example, when using an electron microscope to observe a specimen in a non-vacuum atmosphere, the effect that scattering of a primary charged-particle beam due to a barrier film or a gas present in a non-vacuum space has on the spot shape of the primary charged-particle beam is removed from a signal acquired by a detector. This makes it easy to obtain high-quality images.

First claim

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 performe

Assignees

• Hitachi High Tech Corp

Inventors

• Ominami Yusuke
• Nakahira Kenji
• Tanaka Maki
• Kawanishi Shinsuke

Classifications

• H01J37/28 Primary

  with scanning beams {(H01J37/268, H01J37/292, H01J37/2955 take precedence)} · CPC title

• H01J2237/164

  Particle-permeable windows · CPC title

• H01J2237/2608

  with environmental specimen chamber · CPC title

• H01J2237/2806

  Secondary charged particle · CPC title

• H01J37/20

  Means for supporting or positioning the object or the material; Means for adjusting diaphragms or lenses associated with the support · CPC title