WO2019021420A1

WO2019021420A1 - Charged particle beam device, and method of adjusting charged particle beam device

Info

Publication number: WO2019021420A1
Application number: PCT/JP2017/027255
Authority: WO
Inventors: 高志土橋; 佳史谷口; 央和玉置
Original assignee: 株式会社日立ハイテクノロジーズ
Priority date: 2017-07-27
Filing date: 2017-07-27
Publication date: 2019-01-31

Abstract

A charged particle beam device provided with an irradiation optical system for irradiating a sample with a primary electron beam, and an imaging optical system for causing transmitted electrons transmitted through the sample to form an image and detecting an image of the sample, wherein the irradiation optical system is provided with: an electron gun for emitting the primary electron beam; a condenser aperture in which there is formed an aperture hole for passing a part of the primary electron beam emitted from the electron gun; a first deflector for controlling the trajectory of the primary electron beam that has passed through the aperture hole of the condenser aperture; a condenser lens unit provided with a plurality of condenser lenses for adjusting the degree of parallelism of the primary electron beam, the trajectory of which has been controlled by the first deflector; and an objective lens for forming, on the sample, an image of the aperture hole by the primary electron beam that has been adjusted to parallel light by the condenser lens unit.

Description

Charged particle beam device and method of adjusting charged particle beam device

The present invention relates to a charged particle beam apparatus, and more particularly to a charged particle beam apparatus for observing a sample by irradiating an electron beam to an observation region of the sample and a method of adjusting the charged particle beam apparatus.

As a prior art related to the charged particle beam apparatus according to the present invention, Patent Document 1 describes in paragraph [0009] of the configuration of the charged particle beam optical system shown in FIG. It comprises an aperture stop FS1,

irradiation lenses

17, 18, 19,

aligners

23, 24, a scan aligner 25, an aperture 26 etc. The

irradiation lenses

17, 18, 19 are electron lenses, for example, circular lenses, 4 A polar lens, an octupole lens or the like is used. "

Further, in paragraph [0027] of Patent Document 2, as a [means for solving the problem], “The energy filter according to the present invention has charged particles incident along the optical axis, and the charged particles A first filter which converges in one direction perpendicular to an axis, and a charged particle which is disposed at a subsequent stage of the first filter along the optical axis and which is once converged by the first filter is incident, A second filter having the same length as the first filter along the optical axis, wherein the particle trajectory is adapted to be reversed with respect to the convergence position, the first and second filters Have electric and magnetic quadrupole fields respectively along the optical axis, and the first and second filters realize astigmatic convergence with the electric and magnetic quadrupole fields, respectively. Listed and in paragraph [0033] "Preferably, the first filter, the slit, and the second filter are provided in the direction in which the charged particles travel along the optical axis, and the charged particles are formed of the first and second filters. The charged particle converges on a slit disposed at an intermediate position, the charged particle has an inverted locus with respect to the converging position, and is imaged on the slit by the first and second filters. Aberrations of charged particles are canceled out. "

Patent No. 04135219 Patent No. 04074185

When using a charged particle beam system to irradiate an electron beam (electron beam) at a degree of parallelism of 0.2 mrad or less to a region smaller than several hundred nm on a sample to observe the sample, limit the diameter of the cross section of the electron beam Under the influence of diffraction from the stop, the intensity unevenness of Fresnel stripes may appear on the sample irradiated with the electron beam. This Fresnel fringe is one of the non-uniform intensity distribution derived from the charged particle beam device main body not derived from the sample structure.

If Fresnel stripes are generated on a sample irradiated with the electron beam, there is a problem that when observing the sample with a transmission electron microscope, it becomes impossible to record a transmission image that correctly reflects the sample structure.

When the field of view of the sample is to be made as large as possible with a transmission electron microscope, the spread angle of the electron beam is suppressed and the sample is irradiated with an electron beam having a more uniform intensity distribution in the cross section with parallel beams. A configuration of an electron optical system that can be obtained is required.

As one method for solving this problem, in a normal electron microscope, the electron beam irradiation area is expanded until the Fresnel fringes disappear from the observation field of view, and the sample structure is recorded. However, when such observation is performed, when observing a sample that is weak to electron beam irradiation, if the visual field is moved to a portion irradiated with Fresnel stripes outside the observation visual field of the sample, the region An electron beam with a predetermined amount of abnormality is to be irradiated on the surface, causing damage. As a result, there may occur a case where the near region outside the field of view of the sample can not be used for observation.

That is, the distance between the viewable fields increases due to unnecessary damage, and when the view of the same area is to be observed, the movement distance of the view is compared with the case where the periphery of the view is not damaged by the electron beam irradiation. The problem is that it takes a lot of time and the throughput decreases.

For such problems, Patent Document 1 describes a primary optical system provided with a field stop FS1 and

illumination lenses

17, 18 and 19. However, fresnel fringes on a sample irradiated with an electron beam are described. There is no mention of suppressing the occurrence of In addition, there is also no description of the configuration of an electron optical system that can irradiate a sample with an electron beam having a more uniform intensity distribution in a cross section with a parallel beam while suppressing the spread angle of the electron beam.

Moreover, although it is described in patent document 2 that the aberration of the charged particle imaged on the slit is canceled by the 1st and 2nd filter, the Fresnel fringes on the sample irradiated with the electron beam There is no mention of suppressing the occurrence of In addition, there is also no description of the configuration of an electron optical system that can irradiate a sample with an electron beam having a more uniform intensity distribution in a cross section with a parallel beam while suppressing the spread angle of the electron beam.

The present invention solves the problems of the prior art as described above and provides a charged optical system having an irradiation optical system capable of irradiating a parallel electron beam whose spread angle is suppressed without generating Fresnel fringes on a sample. A particle beam device and a charged particle beam device adjustment method.

In order to solve the problems described above, in the present invention, an irradiation optical system for irradiating the sample with the primary electron beam and an image of transmission electrons transmitted through the sample irradiated with the primary electron beam by the irradiation optical system In a charged particle beam apparatus provided with an imaging optical system for detecting an image of a sample, the irradiation optical system comprises an electron gun for emitting a primary electron beam and a part of the primary electron beam emitted from the electron gun. A condenser diaphragm in which a diaphragm hole to be passed is formed, a first deflector for controlling the trajectory of the primary electron beam passing through the diaphragm hole of the condenser diaphragm, and a primary electron beam whose trajectory is controlled by the first deflector Condenser lens unit including a plurality of condenser lenses for adjusting parallelism, and an objective lens for forming an image of a stop hole by a primary electron beam adjusted to parallel light by the condenser lens unit on a sample .

Further, in order to solve the problems described above, in the present invention, the primary electron beam emitted from the electron gun is irradiated to the sample through the irradiation optical system, and the primary electron beam is irradiated through the irradiation optical system. In a method of adjusting a charged particle beam apparatus, in which transmitted electrons transmitted through a sample are imaged by an imaging optical system to detect an image of the sample, irradiating the sample with the primary electron beam through the irradiation optical system The primary electron beam emitted from the gun is passed through a condenser diaphragm, the trajectory of the primary electron beam passed through the condenser diaphragm is adjusted by a first deflector, and the condenser lens unit including a plurality of condenser lenses is used to perform the first deflector The position of the image plane of the condenser stop by the primary electron beam and the parallelism of the primary electron beam whose orbits have been adjusted by adjusting the position of the image plane by adjusting the position of the image plane by the condenser lens unit The image of the stop capacitor according child beam so as to form an image on the sample by the objective lens.

According to the present invention, it becomes possible to irradiate a parallel electron beam whose spread angle is suppressed without generating Fresnel fringes on the sample, so it is possible to observe the sample in a relatively wide field of view. It became possible to perform sample observation with good throughput.

FIG. 3 is a front view showing a schematic configuration of an irradiation optical system of the charged particle beam device for illustrating the principle of the present invention. FIG. 3 is a front view showing a schematic configuration of an irradiation optical system of the charged particle beam device for illustrating the principle of the present invention. It is a graph showing the relationship between the 1st condenser lens focal distance and the 2nd condenser lens focal distance for making parallel irradiation conditions and condenser diaphragm imaging conditions compatible in the principle of the present invention. It is a block diagram which shows the outline | summary structure of the irradiation optical system of the transmission electron microscope which concerns on Example 1 of this invention. In the comparative example of the transmission electron beam microscope which concerns on Example 1 of this invention, the image of a condenser diaphragm is an image figure of electron beam intensity distribution at the time of a Fresnel fringe appearing on a sample, without forming an image in a sample position. is there. It is a comparative example of the transmission type electron beam microscope which concerns on Example 1 of this invention, and is an image figure of electron beam intensity distribution when a sample image and a fresnel stripe overlap. It is an image figure of the electron beam intensity on a sample when the image of a capacitor | condenser aperture has been able to be imaged on a sample position with the transmission electron microscope concerning Example 1 of this invention. It is an image figure of an observation image when a sample is irradiated with a uniform electron beam by the transmission type electron beam microscope concerning Example 1 of the present invention. FIG. 7 is a front view showing an outline of an irradiation optical system showing a state in which the size of the image of a condenser diaphragm projected onto a sample position is changed using the first deflector in the transmission electron beam microscope according to Example 1 of the present invention. (A) shows a state in which the image of the condenser diaphragm is greatly enlarged and projected onto the sample position, and (b) shows a state in which the image of the condenser diaphragm is magnified relatively small and projected onto the sample position. The image of the electron beam intensity in the sample position which shows the imaging state of the capacitor | condenser aperture by the transmission type electron beam microscope which concerns on Example 1 of this invention WHEREIN: The image of the electron beam intensity before adjusting the imaging state of a capacitor | condenser aperture is shown. The image of the electron beam intensity in the sample position which shows the imaging state of the capacitor | condenser aperture by the transmission type electron beam microscope which concerns on Example 1 of this invention WHEREIN: The image of the electron beam intensity after adjusting the imaging state of a capacitor | condenser aperture is shown. It is an image of the back side focal plane in front of adjustment of parallel irradiation of the irradiation optical system by the transmission electron beam microscope which concerns on Example 1 of this invention. It is an image of the back side focal plane after adjustment of parallel irradiation of the irradiation optical system by the transmission type electron beam microscope which concerns on Example 1 of this invention. It is an image of the amorphous sample which shows the state which divided | segmented the defocusing image of the amorphous sample by the transmission electron beam microscope which concerns on Example 1 of this invention into several segment. It is the analysis image which Fourier-transformed and calculated | required the defocusing image of the amorphous sample by the transmission type electron beam microscope which concerns on Example 1 of this invention for every segment. It is a table | surface which shows the relationship of the irradiation current amount of the electron beam in the irradiation optical system of the transmission type electron beam microscope which concerns on Example 1 of this invention, the diameter of a capacitor | condenser aperture, and the magnification of an irradiation optical system. It is a block diagram which shows schematic structure of the irradiation optical system of the transmission electron microscope which concerns on Example 2 of this invention. It is a block diagram which shows schematic structure of the irradiation optical system of the transmission electron microscope which concerns on Example 3 of this invention. It is a block diagram which shows the schematic structure of the irradiation optical system of the transmission electron microscope which concerns on Example 4 of this invention.

In the present invention, a plurality of irradiation lenses are provided between an aperture for restricting an electron beam and a pre-objective magnetic field, and a plurality of irradiation lenses are used in combination to perform parallel irradiation on a sample placed in the objective lens. And an image of the aperture of the stop that limits the electron beam is formed on the sample (an optical system free from Fresnel fringes).

That is, the present invention makes it possible to irradiate a parallel electron beam whose spread angle is suppressed on a sample placed in an objective lens without generating Fresnel stripes in an irradiation optical system of a charged particle beam apparatus. A plurality of irradiation lenses are provided between the stop for limiting the spread of the electron beam emitted from the electron gun and the front magnetic field of the objective lens, and a plurality of irradiation lenses are used in combination to parallel irradiation on the sample. Electron beam irradiation according to the magnification of the observation area was made possible by imaging the diaphragm on the sample that limits the spread of the electron beam (an optical system free of Fresnel fringes) and changing the electron beam irradiation area It is a thing.

The present invention further provides parallel magnification on the sample and imaging of the image of the aperture of the aperture onto the sample, and by changing the electron beam irradiation area, to the magnification of the observation area. It enables electron beam irradiation according to the requirements.

The principle of the present invention will be described with reference to FIGS. 1 to 3.
FIG. 1 shows a configuration of an irradiation optical system 50 of a charged particle beam device for explaining the principle of the present invention, a condenser diaphragm 2 for limiting the beam diameter of an electron beam 8 emitted from an electron gun 1 and an objective lens A configuration is shown in which three stages of illumination lenses 3, 4, 5 are provided between 60 pre-fields 6.

In the present invention, the parallel irradiation of the electron beam 8 onto the sample 7 placed in the objective lens 60 and the electron beam 8 are performed by using the three-stage irradiation lenses 3, 4 and 5 in combination by the method shown below. An image of the image of the diaphragm hole 201 of the condenser diaphragm 2 to be restricted is formed on the sample 7 (an optical system free of Fresnel fringes), and an electron beam irradiation area is changed to obtain an electron beam according to the magnification of the observation area. I made it possible to irradiate.

The focal length on the side of the front magnetic field 6 (the magnetic field formed on the side of the electron gun 1 by the objective lens 60) by the objective lens 60 in one observation mode is fixed, and the three-stage irradiation lens is used in combination. It is 3,4,5. The three-stage irradiation lenses 3, 4 and 5 are called a first condenser lens 3, a second condenser lens 4 and a third condenser lens 5 from the side closer to the electron gun 1. There is a condenser aperture 2 between the first condenser lens 3 and the electron gun 1.

Inside the electron gun 1, there are an electron source that generates electrons and an accelerating tube that accelerates the electrons to a required acceleration voltage, but the illustration thereof is omitted. Electrons are subject to the effect of electrostatic lenses by the accelerating tube. Therefore, the distance from the first condenser lens 3 to the optical electron source considered is different from the actual distance to the electron gun 1. Therefore, the position of the electron source in consideration of the influence of the electrostatic lens by the accelerating tube is referred to as a virtual light source 200. In this example, a configuration in which three condenser lenses 3, 4 and 5 are disposed below the condenser diaphragm 2 will be described. However, the number of stages of lenses disposed closer to the electron gun 1 than the condenser diaphragm 2 does not matter.

As shown in FIG. 1, (in FIG. 1, front horizontal center of the figure shown in magnetic field 6) the focal point of the previous field 6 of the objective lens 60 from the sample 7 the distance to the d _0. The distance to the focal point of the front magnetic field 6 of the objective lens 60 is not the gap center of the magnetic field lens constituting the objective lens 60 but the position of the effective main surface. The distance from the focal point of the front magnetic field 6 of the objective lens 60 to the third condenser lens 5 is d ₁ , the distance from the third condenser lens 5 to the second condenser lens 4 is d ₂ , and the second condenser lens 4 to the first condenser lens A distance to ₃ is d ₃ , a distance from the first condenser lens 3 to the condenser diaphragm 2 is d _4, and a distance to the virtual light source 200 is a _1G .

The electron beam 8 emitted from the electron gun 1 will be described with respect to the irradiation optical system 50 required to irradiate the sample 7. _Assuming that the distance from the first condenser lens 3 to the image surface 501 of the virtual light source 200 is b _{1 G,} and the focal length of the first condenser lens 3 is f _{1 G} , the relationship of Formula 1 holds from the lens formula.

Assuming that the distance between the second condenser lens 4 and the object surface (the image plane of the first condenser lens 3) 501 is a _2G , a _2G is expressed as (Equation 2).

Similarly, assuming that the distance from the second condenser lens 4 to the image plane 502 of the virtual light source is b _{2 G} , the relationship of (Equation 3) holds from the lens formula when the focal length of the second condenser lens 4 is f _{2 G.}

I thought Similarly, the third condenser lens 5, the table as in the third condenser lens 5 and the object plane and the distance to the (second image plane of the condenser lens 4) 502 and a _3G, a _3G is (Equation 4) Be done.

Similarly, assuming that the distance from the third condenser lens 5 to the image plane 503 of the virtual light source is b _{3 G} , the relationship of (Equation 5) holds from the lens formula when the focal length of the third condenser lens 5 is f ₃ G.

When the distance to 503 (the image plane of the third condenser lens 5) object surface side of the front magnetic field 6 of the objective lens 60 and _{_{a OG,} a OG} is expressed as (number 6).

It becomes.

Assuming that the focal length on the side of the front magnetic field 6 of the objective lens 60 is f _OG , the relationship is given by equation (7).

By using these expressions, it is possible to obtain a relational expression necessary for the focal length of the first condenser lens 3 at the time of parallel irradiation, and a relation such as Expression 8 holds.

An optical system free of Fresnel fringes can determine the focal length in the following manner using the relationship shown in FIG.
When the focal length of the first condenser lens 3 and the capacitor diaphragm second distance _{d 4} and the first condenser lens 3 and _{f 1C,} the distance from the first condenser lens 3 to the image plane 511 of the capacitor the diaphragm 2 as _{b 1C,} ( It becomes a relation like number 9).

The distance between the second condenser lens 4 and the object surface (the image plane of the first condenser lens 3) 511 is a _{2 C} , the focal distance of the second condenser lens 4 is f _{2 C} , the distance to the image plane 512 of the second condenser lens 4 B _{2 C} , and the distance to the object surface (the image surface of the second condenser lens 4) 512 of the third condenser lens 5 a 3 _C , the focal distance of the third condenser lens 5 f _{3 C} , the image of the third condenser lens 5 The distance to the surface 513 is b _{3 C.} Assuming that the distance to the object plane (image surface of the third condenser lens 5) is a _OC , the focal distance is f _OC , and the distance to the image surface 514 is b _OC on the side of the front magnetic field 6 of the objective lens 60, A relationship like (Equation 10) holds.

When considering these equations, it is preferable to determine the excitation of the downstream lens and then consider the conditions. There are six parameters of f _{1 G} , f _{1 C} , f _{2 G} , f _{2 C} , f _{3 G} , f _{3 C in} the optical system for forming the image of the parallel optical system and the aperture hole 201 of the condenser aperture 2 as Since there is only one optical system to be realized, the focal lengths of the respective lenses may be determined to be three in total.

Therefore, FIG. 3 shows an example in which f ₃ _G and f _{3 C} are considered to be equal specific value f _{3 ′} , and the condition of the focal length satisfied by f ₁ _C and f _{2 C} , f _{1 G} and f _{2 G} is plotted. Although a plurality of intersections may appear in the graph drawn by the distance between lenses and the focal distance, the graph 300 shown in FIG. 3 shows the case where there is only one intersection. If the dotted line 301 satisfies the condition of parallel irradiation, and the solid line 302 satisfies the condition of the image formation of the condenser on the sample, the electron beam is irradiated in parallel with the intersection point of the two, and the condition does not have Fresnel stripes. .

The specific value f3 _' is one of the possible focal lengths of the third condenser lens 5, and the focal length of the third condenser lens 5 is several mm to several tens of m or more depending on the designed lens performance. You can change it. Therefore, by changing the focal length f3 _' of the third condenser lens 5, it is possible to obtain an infinite number of compatible conditions for achieving parallel illumination and imaging of the condenser diaphragm on the sample. Among them, aim the irradiation system magnification necessary for the optical system so that the image plane of the third condenser lens 5 coincides with the object plane 513 on the side of the front magnetic field 6 of the objective lens 60 whose focal length is fixed. The optical system of the present invention can be made by

Embodiments of the present invention based on the principle described above will be described below with reference to the drawings.

The optical system of the charged particle beam apparatus according to the first embodiment of the present invention will be described with reference to FIGS. 4 to 14.

FIG. 4 shows a configuration of an optical system in the case of being applied to a transmission electron microscope 100 as a charged particle beam device according to the present embodiment. Note that FIG. 4 shows the configuration of a main optical system as the configuration of the transmission electron microscope 100, and the description of the lens barrel, the control system, and the operation unit is omitted.

The transmission electron microscope 100 shown in FIG. 4 includes an electron gun (light source) 11, a condenser diaphragm 12, a first condenser lens 13, a second condenser lens 14, a third condenser lens 15, a front magnetic field 16 of an objective lens 165, 1 and the irradiation optical system 150 provided with the second deflector 27, and the sample 17 mounted in the objective lens 165 by mounting the sample on the sample holder (not shown), and the objective lens 165 A rear magnetic field 20 of an objective lens 165 formed on the lower side (the side opposite to the electron gun 1), an objective diaphragm 24, a field limiting diaphragm 25, an imaging lens system 21 formed of a plurality of lenses, and a detector 22 are provided. An imaging optical system 250 is provided.

In the transmission electron microscope 100 shown in FIG. 4, the configuration of the irradiation optical system 150 indicated by the part numbers 11 to 15 and 165 is the part numbers 1 to 5 of the irradiation optical system 50 described in FIGS. Corresponds to 60.

In the transmission electron microscope 100 shown in FIG. 4, the electron beam (primary electron beam) 18 on the irradiation system side generated by the electron gun 11 is limited by the aperture 1201 formed in the condenser aperture 12 and The sample 17 placed inside the objective lens 165 is irradiated via the condenser lens 13, the second condenser lens 14, the third condenser lens 15, and the front magnetic field 16 of the objective lens 165.

Electrons (transmission electrons) 23 generated on the side of the imaging optical system 250 by transmitting through the sample 17 pass through the back magnetic field 20 of the objective lens, and then pass through the objective diaphragm 24 and the field limiting diaphragm 25 to form an imaging lens. The light is imaged on the detector 22 via the system 21 and detected.

In this configuration, the first deflector 26 is disposed in the vicinity of the condenser diaphragm 12. The first deflector 26 may be located upstream of the first condenser lens 13 and may be disposed in a manner such that the electron gun 11 upstream of the condenser diaphragm 12 or the condenser diaphragm 12 is interposed. The second deflector 27 is a deflector necessary to check that the image of the aperture 1201 of the condenser aperture 12 is imaged on the sample 17 installed inside the objective lens 165. It needs to be upstream.

The condenser diaphragm 12 is a diaphragm that limits the size (diameter) of the electron beam irradiated to the sample 17. The size (diameter) of the diaphragm hole 1201 is about several micrometers to several mm at the maximum. The condenser diaphragm 12 may be energized and heated for the purpose of preventing contamination due to the irradiation of the electron beam 18.

The first condenser lens 13, the second condenser lens 14 and the third condenser lens 15 under the condenser aperture 12 may be either a magnetic field lens or an electric field lens, but they are not multipole lenses but lenses having rotationally symmetric fields. .

The objective lens 165 forming the pre-magnetic field 16 may be either a magnetic lens or an electrostatic lens. In the present embodiment, the case of a magnetic lens will be described. The focal length of the front magnetic field 16 of the objective lens 165 and the rear magnetic field 20 of the objective lens 165 change according to the amount of current supplied to the objective lens 165. Normally, the conditions are established with the strengths of the front magnetic field 16 and the rear magnetic field 20 of the objective lens 165 constant (the respective focal distances are constant), but the excitation of the objective lens 165 is turned off to create a special optical system. You may make the optical system of an Example.

Electrons (transmission electrons) 23 transmitted through the sample 17 enter the imaging lens system 21 on the side of the imaging optical system 250 while receiving a focusing effect by the back magnetic field 20 of the objective lens 165 formed downstream of the sample 17 . The present embodiment shows a configuration in which the imaging lens system 21 is provided with three stages of electron lenses, but the imaging lens system 21 is usually configured by one to about five stages of electron lenses.

In this embodiment, the case where three crossovers 19 are formed between the first condenser lens 13 and the front magnetic field 16 of the objective lens 165 is shown. However, the present embodiment is not limited to this. That is, the number of crossovers 19 is not limited to three as shown in FIG. 4, and there is no crossover 19 between the first condenser lens 13 and the second condenser lens 14, or the second condenser lens 14 and the third condenser lens 14. It is possible to take a plurality of combinations, such as not having the crossover 19 between the condenser lenses 15.

Further, in this embodiment, an example is shown in which the irradiation optical system 150 is adjusted so that the image plane of the third condenser lens 5 coincides with the object plane 513 of the front magnetic field 16 of the objective lens 165 whose focal length is fixed. . However, the present invention is not limited to this, and even when the focal length of the front magnetic field 16 of the objective lens 165 is changed, the object plane of the front magnetic field 16 of the objective lens 165 accompanying the change of the focal length The position of the image plane of the third condenser lens 5 may be adjusted in accordance with the fluctuation.

<Effect of applying this embodiment>
The electron beam intensity on the sample 17 when the irradiation optical system 150 according to the present embodiment is not used will be described with reference to FIG.

When a small region on the sample is irradiated with parallel electron beams, Fresnel fringes 53 appear in the observed image 51 in a general-purpose transmission electron microscope that does not use the irradiation optical system 150 according to the present embodiment. The Fresnel fringes 53 can not be seen when the image plane (corresponding to 515 in FIG. 2) of the condenser diaphragm 12 is formed on the sample 17, and becomes larger as the image plane moves away from the sample 17.

A sample image obtained by the detector 22 when the irradiation optical system 150 according to the present embodiment is not used will be described with reference to FIG.

When there are a plurality of observation targets 62 in the field of view, and the Fresnel stripes 63 (corresponding to the Fresnel stripes 53 in FIG. 5) overlap, the image 61 obtained by the detector 22 is as shown in FIG. Although it is known that the observation target 62 exists in the peripheral visual field in the image 61 due to the influence of the Fresnel stripes 63, the influence of the Fresnel stripes 63 is mixed in addition to the information derived from the observation target 62 compared with the center of the visual field.

The electron beam intensity on the sample 17 placed inside the objective lens 165 when using the irradiation optical system 150 according to the present embodiment will be described with reference to FIG.

When the irradiation optical system 150 according to the present embodiment is used, the first to third condenser lenses 13 to 15 are adjusted to satisfy the conditions as described with reference to FIGS. By adjusting so that the image of the stop hole 1201 of the condenser stop 12 is formed on the sample 17 in this manner, the electron beam intensity in the image 71 obtained by the detector 22 is as shown in FIG. The Fresnel fringes 53 do not appear, and the shape of the electron beam 18 on the sample 17 matches the shape of the aperture 1201 of the condenser aperture 12.

Under normal electron microscope observation, small dirt attached around the aperture 1201 of the condenser aperture 12 is enlarged by the Fresnel fringes 53. On the other hand, in the irradiation optical system 150 according to the present embodiment, since the irradiation optical system 150 can be adjusted so that the Fresnel fringes 53 are not generated, the influence on the contamination of the condenser diaphragm 12 can also be reduced. is there.

An image 81 obtained by the detector 22 when the irradiation optical system 150 according to the present embodiment is used will be described with reference to FIG.

The image 81 shown in FIG. 8 is obtained by using the electron beam 18 in a state in which the image of the aperture hole 1201 of the condenser aperture 12 is formed on the sample 17 as described in FIG. An image 81 of a region including the observation target 82 is shown. When there are a plurality of observation targets 82 in the field of view of the image 81, data of the observation target 82 is acquired in all the regions to which the electron beam 18 is irradiated without being affected by the Fresnel fringes 63 as shown in FIG. It is possible to

<Position of deflector>
The position of the first deflector 26 in the irradiation optical system 150 according to the present embodiment will be described with reference to FIG.

FIG. 9 shows the configuration of an irradiation optical system 150 according to the present embodiment. In the configuration shown in FIG. 9, the electrons from the first condenser lens 13 to the third condenser lens 15 are combined by using three stages of condenser lenses disposed between the condenser diaphragm 12 and the front magnetic field 16 of the objective lens in combination. It shows a state in which the trajectory of the beam 18 is changed.

Comparing the trajectory 91 of the electron beam on the side of (a) in FIG. 9 with the trajectory 92 of the electron beam on the side of (b) in FIG. 9, the crossover 93 in the trajectory 91 of the electron beam on the side of (a) The height of the position and the position of the crossover 94 in the trajectory 92 of the electron beam on the side of (b) are different. When the position of the crossover changes around the first deflector 26, the effect of the first deflector 26 on the electron beam changes.

In order to reduce the influence of the change in the position of the crossover of the electron beam trajectory, the first deflector 26 of the irradiation optical system 150 according to the present embodiment starts from the position where the crossover of the electron beam 18 occurs. It is preferable to arrange them as far apart as possible. In the present embodiment, the first deflector 26 is disposed between the condenser diaphragm 12 and the first condenser lens 13 as a position satisfying such conditions.

Also, for the same reason, the first deflector 26 can be placed not only between the condenser diaphragm 12 and the first condenser lens 13 but also from the position where the crossover of the electron beam trajectory occurs. It may be between the third condenser lens 15 and the front magnetic field 16 of the objective lens as a distant position.

<Adjustment method of condenser aperture imaging>
An adjustment method in the case of forming an image of the diaphragm hole 1201 of the condenser diaphragm 12 on the sample 17 disposed inside the objective lens 165 will be described with reference to FIGS. 10 and 11. FIG. By using the second deflector 27 on the side of the electron gun 11 with respect to the condenser diaphragm 12, the imaging state of the image of the diaphragm hole 1201 of the condenser diaphragm 12 to the position where the sample 17 is installed inside the objective lens 165 Can be judged.

As a specific method, one image is acquired by the detector 22 in a state where the image of the diaphragm hole 1201 of the condenser diaphragm 12 is not formed at the position where the sample 17 is installed inside the objective lens 165. The second deflector 27 is vibrated in a time shorter than the imaging time required for At this time, an image captured by the detector 22 is an image 101 having an intensity distribution as shown in FIG. In the image 101,

circular intensity distributions

103 and 104 corresponding to the image of the aperture hole 1201 of the condenser aperture 12 projected to the position where the sample 17 is placed are observed. This represents the appearance of the electron beam on the sample 17 vibrating in a short time.

On the other hand, the irradiation optical system 150 is adjusted to satisfy the conditions as described with reference to FIGS. 1 to 3 so that the image of the stop hole 1201 of the condenser stop 12 is formed at the position where the sample 17 is installed. In this state, the second deflector 27 is vibrated in a time shorter than the imaging time required for acquiring one image by the detector 22.

At this time, the image captured by the detector 22 is an image having a circular intensity distribution 112 corresponding to the image of the aperture hole 1201 of the condenser aperture 12 projected to the position where the sample 17 is installed, as shown in FIG. 111 is obtained.

In the image 111, in the region of the circular intensity distribution 112 corresponding to the image of the aperture 1201 of the condenser aperture 12, the intensity of the sample position hardly changes and is constant even when the second deflector 27 is vibrated.

In order to form an image of the diaphragm hole 1201 of the condenser diaphragm 12 at a position where the sample 17 is installed, the irradiation optical system 150 needs to be under the condition that the diaphragm hole 1201 of the condenser diaphragm 12 can be seen by the detector 22 . For example, a method may be considered in which the condenser diaphragm 12 in which the diaphragm hole 1201 having a smaller diameter than the diaphragm used in the observation condition is formed is prepared and used for adjustment.

As another method, the magnification of the imaging optical system 250 is reduced only at the time of adjustment so that the image of the diaphragm hole 1201 of the condenser diaphragm 12 can be reliably seen by the detector 22, and the image of the diaphragm hole 1201 of the condenser diaphragm 12 is There is also a method of examining the imaging state. As another method, there is also a method of performing adjustment by making an edge of a diaphragm hole of a condenser diaphragm visible by using an image shift disposed under an objective lens mounted on a normal electron microscope.

<Method of adjusting parallel irradiation>
In the irradiation optical system 150 according to the present embodiment, an adjustment method for irradiating the electron beam 18 in parallel to the sample position 17 will be described with reference to FIGS. 12 and 13.

As one method of adjusting the parallel irradiation of the electron beam 18, there is a method of changing an imaging lens system in a normal transmission electron microscope to a diffraction pattern acquisition mode and adjusting. The object plane of the imaging lens system 21 is adjusted to the back focal plane of the back magnetic field 20 of the objective lens 165 in advance, and the angular distribution of the electron beam at the position where the sample 17 is placed inside the objective lens 165 Check.

FIG. 12 shows an example of an image 121 acquired by the detector 22 when the parallel illumination of the electron beam 18 on the sample position 17 is insufficient. In the image 121 acquired in this state, the image 122 of the aperture hole 1201 of the condenser aperture 12 by the primary electron beam is spread in the image 121. In this state, the electron beam 18 is incident on the sample position 17 at various angles. By adjusting the first to third condenser lenses 13 to 15 while observing the intensity distribution, the incident angle of the electron beam 18 incident on the sample position 17 is adjusted.

FIG. 13 shows an example of the image 131 acquired by the detector 22 in a state in which the incident angle of the electron beam 18 is adjusted and the parallel irradiation of the electron beam 18 to the sample position 17 is sufficient. When parallel irradiation is obtained, the electron beam 18 does not spread, and the image of the aperture 1201 of the condenser aperture 12 is observed as a spot 132 having a minute diameter.

In the adjustment method of parallel irradiation of the electron beam 18 incident on the sample position 17 described above, the adjustment is performed by looking at the intensity of the image of the condenser diaphragm 12 formed on the back focal plane by the lower magnetic field 20 of the objective lens. The

Several methods can be considered as a method of adjusting the object plane of the imaging lens system 21 to match the back focal plane of the back magnetic field 20 of the objective lens 165. For example, an amorphous sample is placed at a position where the sample 17 is to be placed, and the excitation of the front magnetic field 16 of the objective lens 165 or the excitation of the rear magnetic field 20 of the objective lens 165 is changed to obtain a defocused image There are methods of dividing an acquired image into a plurality of regions and performing Fourier transform.

A method of estimating the parallelism in the field of view of the electron beam 18 incident on the position where the sample 17 is to be installed from the single defocus image 141 of the amorphous sample regarding the adjustment method of parallel irradiation, using FIG. 14 and FIG. explain.

FIG. 14 shows a defocused image 141 obtained by irradiating the amorphous sample placed at the position where the sample 17 is placed with the electron beam 18. The defocus image 141 is divided into a plurality of small segments 143. The size of the segment 143 to be divided varies depending on the number of pixels of the detector 22 and the parallelism required for the electron beam 18 incident on the amorphous sample. Generally speaking, it is easier to determine the difference in the incident angle of the electron beam 18 on the amorphous sample in the image if it is finely divided.

FIG. 15 shows an analysis image 151 obtained by performing Fourier transform on each of the segments 143 divided in FIG. In the analysis image 151, a difference appears between the Fourier transform result 152 of the central portion and the Fourier transform result 153 of the peripheral portion. It is possible to estimate the difference in parallelism between the center and the peripheral visual field from, for example, the information of the ellipticity and the defocus amount of the Fourier transform

results

152 and 153 for each segment.

In the adjustment of parallel irradiation of the electron beam 18 described above, the parallelism was measured from one amorphous image, but there is also a method of using an existing diffractogram as another method.

<Optical system setting method>
A method of reducing the conditions necessary for adjustment by linking the diameter of the aperture hole 1201 of the condenser aperture 12 and the magnification in the setting method of the irradiation optical system 150 according to the present embodiment will be described with reference to FIG.

In the irradiation optical system 150 according to the present embodiment, the condenser diaphragm 12 adjusts the amount of irradiation current of the electron beam 18 to be irradiated to the sample 17 disposed inside the objective lens 165. In order to increase the amount of irradiation current applied to the sample 17, it is necessary to increase the diameter of the aperture 1201 of the condenser aperture 12. However, if the diameter of the aperture 1201 of the condenser aperture 12 is increased, the irradiation area on the sample also becomes large, and the electron beam 18 is also irradiated to the area outside the observation field of view, damaging the sample 17. There is a possibility of

Therefore, in the present embodiment, the first condenser lens 13 and the second condenser lens are used to irradiate the same area of the sample 17 before and after the diameter of the diaphragm hole 1201 of the condenser diaphragm 12 is increased. 14 The strength of the third condenser lens 15 is changed to adjust the reduction ratio of the irradiation optical system 150.

A table 160 in FIG. 16 shows a setting example of the irradiation optical system 150 when the diameter (diaphragm diameter) 162 of the diaphragm hole 1201 of the condenser diaphragm 12 and the magnification 163 are linked. In this table 160, it is shown that the diameter (diaphragm diameter) 162 of the aperture hole 1201 of the condenser aperture 12 and the irradiation current amount 161 have a one-to-one relationship.

On the other hand, when the magnification 163 of the irradiation optical system 150 is 1k (k is an arbitrary unit amount), 2k and 4k, the diameter (diaphragm diameter) 162 of the aperture 1201 is 1R (R is an arbitrary unit amount), By setting 2R and 4R, 9 conditions can be set. In Table 160, the same alphabet letters are described in the column where the value obtained by multiplying the diameter (diaphragm diameter) 162 of the diaphragm hole 1201 and the magnification 163 is the same value.

In this table 160, when the irradiation current amount 161 is 1I (I is an arbitrary unit amount) and the diameter (diaphragm diameter) 162 of the diaphragm hole 1201 is 1R, the C condition of 4k times the diameter of the diaphragm hole 1201 (diaphragm diameter By changing only 162), it is understood that the irradiation current amount 161 when the magnification 163 is 1 k can be diverted to the condition of 16I.

For example, in the case of FIG. 16, the required irradiation current amount 161 is three types 1I, 4I and 16I, but in the relationship between the diameter (diaphragm diameter) 162 of the diaphragm hole 1201 of the condenser diaphragm 12 and the magnification 163 With respect to the optical conditions, five conditions of A to D may be set, and the time and effort for setting conditions can be reduced.

According to the present embodiment, it is possible to simultaneously form an image of the condenser diaphragm on the sample while changing the electron beam irradiation area simultaneously while the electron beam is parallel irradiated onto the sample. Thus, it became possible to irradiate the electron beam according to the magnification of the observation area.

In the configuration of the irradiation optical system 150 shown in FIG. 4 in the first embodiment, the first deflector 26 and the second deflector 27 are disposed with the condenser diaphragm 12 interposed therebetween.

On the other hand, in the present embodiment, for the purpose of expanding the adjustment range of the irradiation area of the electron beam at the position where the sample 17 is placed, as shown in FIG. The fourth condenser lens 171 is provided between them.

The configuration of the irradiation optical system 170 according to the present embodiment shown in FIG. 17 is the same as that of the irradiation optical system 150 shown in FIG. 4 described in the first embodiment except the fourth condenser lens 171. The description of the configuration of will be omitted.

In the configuration in which the fourth condenser lens 171 is disposed between the condenser diaphragm 12 and the second deflector 27 and the electron gun 11 in the irradiation optical system 170 according to the present embodiment shown in FIG. By adjusting the focal position 172 of the fourth condenser lens 171 by changing the focal length, the electron beam 178 adjusted by the first to

third condenser lenses

13, 14 and 15 downstream of the condenser diaphragm 12 is It is possible to widen the adjustment range of the irradiation area and the irradiation current amount at the position where the sample 17 is installed.

Furthermore, by adjusting the excitation condition of the fourth condenser lens 171, it is also possible to control the amount of spherical aberration of the electron beam 178 at the position where the sample 17 is installed inside the objective lens 165. In addition, even when the position of the virtual light source (corresponding to 200 in FIG. 1) in the electron source of the electron gun 1 changes, the fourth condenser lens 171 is not adjusted downstream of the condenser diaphragm 12. Changes can be absorbed.

According to this embodiment, in addition to the effect of lightening in Embodiment 1, the adjustment range of the irradiation area of the electron beam 178 at the position where the sample 17 is installed inside the objective lens 165 is shown in FIG. Compared with the case of 1, it can be enlarged.

The illumination optical system 180 according to the third embodiment of the present invention will be described with reference to FIG.

In the configuration of the irradiation optical system 180 according to the present embodiment shown in FIG. 18, the configuration of the irradiation optical system 150 shown in FIG. 4 described in the first embodiment except for the fourth condenser lens 171 and the fifth condenser lens 181 Since they are the same, the description of their configuration is omitted.

In an irradiation optical system 180 including a five-stage condenser lens in which a fifth condenser lens 181 is disposed upstream of the fourth condenser lens 171 (on the side of the electron gun 11) as shown in FIG. By changing the strength with the fifth condenser lens 181, a virtual light source (equivalent to 200 in FIG. 1) apparently inside the electron gun 11 without changing the image plane position 182 made by the fourth condenser lens 171 It is possible to adjust the height of the

This makes it possible to arbitrarily adjust the amount of irradiation current of the electron beam 188 at the position where the sample 17 is installed inside the objective lens 165 while the diameter of the aperture hole 1201 of the condenser aperture 12 is fixed.

In the irradiation optical system 180 consisting of the

condenser lens

13, 14, 15, 171, 181 according to this embodiment, the diameter of the aperture hole 1201 of the condenser aperture 12 is fixed, and the sample 17 inside the objective lens 165 is used. It is possible to change the amount of irradiation current of the electron beam 188 at the installation position. As a result, it is possible to redundantly prepare a diaphragm hole 1201 having a diameter with a high degree of utilization with respect to the diameter of a diaphragm hole 1201 normally provided with four to seven condenser diaphragms 12. By forming a plurality of diaphragm holes 1201 having a diameter frequently used as described above, one condenser diaphragm 12 can be used for a relatively long time, and the replacement frequency of the condenser diaphragm 12 can be reduced.

As described above, according to the present embodiment, in addition to the effects described in the first embodiment, the irradiation area of the electron beam 188 at the position where the sample 17 is placed inside the objective lens 165 (the image It becomes possible to independently control the size of the image of the condenser diaphragm 12 and the amount of irradiation current (dose amount), and it becomes possible to irradiate the electron beam according to the observation region and the sample to be observed.

In the first to third embodiments, the configuration in which the three-

stage condenser lenses

13, 14 and 15 are provided between the condenser diaphragm 12 and the front magnetic field 16 of the objective lens 165 has been described. The stepped structure is described with reference to FIG.

The configuration of the irradiation optical system 190 according to the present embodiment shown in FIG. 19 is the same as that of FIG. 4 except that the third condenser lens 15 in the configuration of the irradiation optical system 150 shown in FIG. Since the configuration is the same as that described, the description of those configurations is omitted.

Like the illumination optical system 190 shown in FIG. 19, the condenser lens group is formed by the first condenser lens 13 and the second condenser lens 14 except for the third condenser lens 15 of the illumination optical system 150 shown in FIG. Also in the optical system described above, it is possible to create an imaging optical system in which the image of the stop hole 1201 of the condenser stop 12 is formed at the position where the sample 17 is placed. The size of the image of the aperture hole 1201 of the condenser aperture 12 (the diameter of the electron beam 18 irradiated at the location where the sample 17 is placed) formed on the position where the sample 17 is placed inside the objective lens 165 can not be changed. However, by adjusting the first condenser lens 13 and the second condenser lens 14, it is possible to irradiate a beam parallel to the position where the sample 17 is placed.

According to the present embodiment, unlike the case where the third condenser lens 15 is provided as described in the first embodiment, it is not possible to obtain conditions that can cope with a plurality of wide irradiation areas, but one condenser aperture diameter On the other hand, it is possible to create irradiation conditions limited to one or two conditions.

In addition, the fourth condenser lens 171 described in FIG. 17 in the second embodiment is added to the configuration shown in FIG. 19, and the position of the virtual light source is changed to install the sample 17 inside the objective lens 165. The size of the image (the diameter of the electron beam 18 irradiated to the sample position 17) of the aperture 1201 of the condenser aperture 12 imaged at the position can be changed.

Furthermore, by adding the fourth condenser lens 171 and the fifth condenser lens 181 described in FIG. 18 in the third embodiment to the configuration shown in FIG. The size of the image 1201 (the diameter of the electron beam 18 irradiated to the position where the sample 17 is placed) and the amount of irradiation current can be adjusted independently.

As mentioned above, although the invention made by the present inventor was concretely explained based on an example, the present invention is not limited to the above-mentioned example, and it can be variously changed in the range which does not deviate from the gist Needless to say. For example, the embodiments described above are described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the configurations described. In addition, with respect to a part of the configuration of each embodiment, it is possible to add, delete, and replace other configurations.

1, 11 ... electron gun 2, 12 ... condenser aperture 3, 13 ... first condenser lens 4, 14 ...

second condenser lens

5, 15 ... third condenser lens 6, 16 · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ... Transmission electron 24 ... Objective stop 25 ... Limited field stop 26 ... First deflector 27 ...

Second deflector

50, 150, 170, 180, 190 ... Irradiation

optical system

60 , 165 ... objective lens 160 ... imaging optical system 171 ... fourth condenser lens 181 ... fifth condenser lens.

Claims

An irradiation optical system for irradiating the sample with a primary electron beam;
A charged particle beam apparatus comprising: an imaging optical system for imaging transmitted electrons generated from the sample irradiated with the primary electron beam by the irradiation optical system to detect an image of the sample;
The irradiation optical system is
An electron gun for emitting the primary electron beam;
A condenser diaphragm in which a diaphragm hole is formed for passing a part of the primary electron beam emitted from the electron gun;
A first deflector for controlling the trajectory of the primary electron beam that has passed through the aperture hole of the condenser aperture;
A condenser lens unit including a plurality of condenser lenses for adjusting the parallelism of the primary electron beam whose orbit is controlled by the first deflector;
A charged particle beam apparatus, comprising: an objective lens configured to form an image of the stop hole by the primary electron beam adjusted to be parallel light by the condenser lens portion on the sample.
The charged particle beam apparatus according to claim 1, wherein the charged particle beam apparatus is a transmission electron microscope, and the imaging optical system is the primary electron beam whose parallelism is adjusted by the irradiation optical system. A charged particle beam apparatus, comprising: forming an image of transmitted electrons transmitted through the sample irradiated with the light; and detecting an image of the formed transmitted electrons.
The charged particle beam device according to claim 1, wherein the condenser lens unit includes three condenser lenses, and the three condenser lenses are parallel to the primary electron beam whose orbit is controlled by the first deflector. A charged particle beam device comprising: a function of adjusting a degree; and a function of adjusting alignment of an image surface of the condenser lens portion to an object surface of the objective lens.
The charged particle beam apparatus according to claim 1, wherein the irradiation optical system includes a second deflector at a position facing the first deflector with the condenser diaphragm interposed therebetween. Wire equipment.
5. The charged particle beam device according to claim 4, wherein the irradiation optical system adjusts the diameter of the primary electron beam to be collimated by the condenser lens unit between the second deflector and the electron gun. And a first condenser lens for adjusting an irradiation current.
6. The charged particle beam device according to claim 5, wherein the irradiation optical system adjusts an irradiation current amount of the primary electron beam to be irradiated to the sample between the first condenser lens and the electron gun. A charged particle beam device further comprising a second condenser lens.
The primary electron beam emitted from the electron gun is irradiated to the sample through the irradiation optical system,
An adjusting method of a charged particle beam apparatus, which images transmission electrons generated from the sample irradiated with the primary electron beam through the irradiation optical system by an imaging optical system and detects an image of the sample. ,
Irradiating the sample with the primary electron beam through the irradiation optical system;
Passing the primary electron beam emitted from the electron gun through a condenser aperture;
Adjusting a trajectory of the primary electron beam having passed through the condenser aperture by a first deflector;
Adjusting a degree of parallelism of the primary electron beam whose orbit is adjusted by the first deflector by a condenser lens unit including a plurality of condenser lenses, and adjusting a position of an image plane of the condenser diaphragm by the primary electron beam;
Charged particle beam characterized in that an image of the condenser diaphragm by the primary electron beam adjusted to parallel light by the condenser lens portion and the position of the image plane adjusted is formed on the sample by an objective lens How to adjust the device.
8. The method for adjusting a charged particle beam device according to claim 7, wherein the charged particle beam device is a transmission electron microscope, and the degree of parallelism and the position of the image plane of the condenser diaphragm through the irradiation optical system. A charged particle beam device characterized in that an electron beam transmission image of the sample is detected by forming an image of transmission electrons transmitted through the sample irradiated with the primary electron beam adjusted by the imaging optical system with an imaging optical system. How to adjust the
8. The method of adjusting a charged particle beam device according to claim 7, wherein a trajectory of said primary electron beam is adjusted by said first deflector, and said first deflector is constituted by a plurality of said condenser lenses of said condenser lens portion. Adjustment of the parallelism of the primary electron beam whose orbit is adjusted, and adjustment of aligning the image plane of the condenser diaphragm with the object plane of the objective lens Method.
The adjustment method of a charged particle beam device according to claim 7, wherein the second deflector is disposed at a position facing the first deflector across the condenser diaphragm of the irradiation optical system. And adjusting the optical axis through which the primary electron beam passes from the target to the objective lens.
11. The method of adjusting a charged particle beam device according to claim 10, wherein the second deflector is used to swing the optical axis of the primary electron beam that has passed through the condenser diaphragm, and the first optical beam is deflected. The image by the transmission electron transmitted through the sample irradiated with the next electron beam is detected by the imaging optical system, and the condenser lens unit is used based on the image by the transmission electron detected by the imaging optical system. A method of adjusting a charged particle beam device, comprising adjusting a state of imaging of an image of a condenser diaphragm on the sample.
11. The method of adjusting a charged particle beam device according to claim 10, further comprising: using a first condenser lens disposed between the second deflector of the irradiation optical system and the electron gun, paralleling at the condenser lens portion. And adjusting a diameter of the primary electron beam to be adjusted to light and an irradiation current of the primary electron beam to be irradiated to the sample.
The charged particle beam apparatus according to claim 12, wherein the aspheric aberration of the primary electron beam irradiated to the sample is adjusted using the first condenser lens. How to adjust the device.
13. The method of adjusting a charged particle beam device according to claim 12, further comprising: a first condenser lens disposed on the side of the second deflector between the second deflector of the irradiation optical system and the electron gun; Adjusting the diameter of the primary electron beam adjusted to parallel light by the condenser lens unit and the irradiation current of the primary electron beam irradiated to the sample using the second condenser lens installed on the electron gun side And a method of adjusting a charged particle beam device.