Focused ion beam apparatus and control method therefor

Abstract

To provide a focused ion beam apparatus that can easily perform processing of a sample.SOLUTION: A focused ion beam apparatus comprises: an electron beam barrel; an ion beam barrel; a sample holder that is capable of tilting a sample with respect to an electron beam and an ion beam; and a control unit that defines an actual working space specified by a scanning point of the electron beam and a focusing distance of the electron beam, acquires a plurality of electron microscope images of the sample having mutually different observation azimuths, creates a three-dimensional model including actual space information of the sample based on the plurality of electron microscope images, changes a posture of the sample in accordance with an operation of the sample holder, acquires, from the three-dimensional model, a two-dimensional image of the sample when viewed from an irradiation axis of the ion beam, determines a predetermined range for irradiation of the ion beam using the two-dimensional image, and processes the sample by irradiating the predetermined range with the ion beam using the ion beam barrel.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD An embodiment of the present invention relates to a focused ion beam device and a control method thereof. [Background technology]

[0002] As semiconductor devices become increasingly miniaturized and complex, defect analysis to identify the causes of malfunctions and failures in semiconductor devices is becoming increasingly important. Among these, transmission electron microscope (TEM) observation is widely used for structural analysis as a method that allows for high-precision observation of microscopic regions within a sample.

[0003] In recent years, TEM specimen preparation technology using a focused ion beam (FIB) has been attracting attention. Using a focused ion beam device, a focused ion beam, which is formed by focusing metal ions or the like to the nanometer level, can be irradiated onto the surface of a sample, allowing for precise processing of the sample surface. By detecting the secondary electrons emitted when the focused ion beam is irradiated onto the sample surface, observation can be made using a scanning ion microscope (SIM) image. Therefore, for example, processing using a focused ion beam is often performed while observing the SIM image.

[0004] Furthermore, in order to confirm the degree of processing of a sample by a focused ion beam, a focused ion beam device combined with a scanning electron microscope (SEM) is sometimes used. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] U.S. Patent No. 11,355,305 [Patent Document 2] U.S. Patent No. 10,453,646 [Patent Document 3] U.S. Patent No. 11,355,307 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the embodiments is to provide a focused ion beam apparatus and a control method thereof that can easily process a sample. [Means for solving the problem]

[0007] a sample holder configured to hold the sample and tilt the sample relative to the electron beam and the ion beam; and a control unit configured to define a real working space defined by the scanning point of the electron beam and the focusing distance of the electron beam, to irradiate the sample with the electron beam using the electron beam holder, to obtain multiple electron microscope images of the sample with different observation orientations, to create a three-dimensional model including real space information of the sample based on the multiple electron microscope images, to change the attitude of the sample in accordance with the operation of the sample holder, to obtain a two-dimensional image of the sample as viewed from the irradiation axis of the ion beam from the three-dimensional model, to determine a predetermined range to be irradiated with the ion beam using the two-dimensional image, and to process the sample by irradiating the predetermined range with the ion beam using the ion beam holder. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram of a focused ion beam device according to a first embodiment. [Figure 2] 2 is a schematic diagram showing an example of a diaphragm of an electron beam e used in the focused ion beam apparatus of the first embodiment. FIG. [Figure 3] FIG. 1 is a schematic diagram showing the relationship between the focal depth of an SEM and a SIM image. [Figure 4]1 is a schematic diagram showing an example of an aperture in a plane perpendicular to the plane through which the electron beam e passes, which is used to make the focal depth shallow in the electron beam lens barrel of this embodiment. FIG. [Figure 5] 10 is a flowchart of a control method for the focused ion beam apparatus according to the present embodiment. [Figure 6] 1 is a schematic diagram showing an example of a three-dimensional model including real space information of a sample S. FIG. [Figure 7] FIG. 10 is a schematic diagram of a sample holder according to a second embodiment. [Figure 8] FIG. 10 is a schematic diagram of a sample holder according to a second embodiment. [Figure 9] FIG. 10 is a schematic diagram of a sample holder according to a second embodiment.

[0009] Hereinafter, embodiments will be described with reference to the drawings. In the drawings, the same or similar parts are denoted by the same or similar reference numerals.

[0010] In this specification, in order to indicate the positional relationship of parts, etc., the upward direction of the drawing will be described as "up" and the downward direction of the drawing will be described as "down." In this specification, the concepts of "up" and "down" do not necessarily refer to the direction of gravity.

[0011] (First embodiment) The focused ion beam device of this embodiment includes an electron beam column that irradiates a sample with an electron beam having a shallow focal depth, an ion beam column that processes the sample by irradiating the sample with an ion beam, a detector that detects electrons generated from the sample, a sample holder that holds the sample and can tilt the sample with respect to the electron beam and the ion beam, and a control unit that defines a real working space defined by the scanning point of the electron beam and the focusing distance of the electron beam, irradiates the sample with the electron beam using the electron beam column, acquires multiple electron microscope images of the sample with different observation orientations, creates a 3D model containing real space information of the sample based on the multiple electron microscope images, changes the attitude of the sample in accordance with the operation of the sample holder, acquires from the 3D model a 2D image of the sample as viewed from the irradiation axis of the ion beam, determines a predetermined range to be irradiated with the ion beam using the ion beam column, and processes the sample by irradiating the predetermined range with the ion beam.

[0012] The control method for a focused ion beam device of this embodiment uses an electron beam column that irradiates a sample with an electron beam having a shallow focal depth, an ion beam column that processes the sample by irradiating the sample with an ion beam, a detector that detects electrons generated from the sample, and a sample holder that holds the sample and can tilt the sample with respect to the electron beam and the ion beam. The method defines a real workspace defined by the scanning point and focal length of the electron beam, irradiates the sample with the electron beam using the electron beam column, acquires multiple electron microscope images of the sample with different observation orientations, creates a 3D model containing real-space information of the sample based on the multiple electron microscope images, changes the attitude of the sample in response to the operation of the sample holder, acquires a 2D image of the sample as viewed from the ion beam irradiation axis from the 3D model, uses the 2D image to determine a predetermined area to be irradiated with the ion beam, and processes the sample by irradiating the predetermined area with the ion beam using the ion beam column. The virtual space and the 3D model are displayed on a display unit 34. The operator can view and operate the virtual space and the 3D model.

[0013] FIG. 1 is a schematic diagram of a focused ion beam device 100 according to this embodiment.

[0014] The focused ion beam device 100 includes an electron beam column 2, an ion beam column 4, a secondary electron detector 6, a sample holder 8, an FIB control unit 20, an electron beam control unit 22, an image forming unit 24, a sample holder control unit 28, a control unit 30, an input unit 32, and a display unit 34.

[0015] The sample holder 8 is placed inside a sample chamber (not shown). A sample S is placed on the sample holder 8. The sample holder control unit 28 rotates, moves, etc. the sample holder 8. This controls the sample S to a position suitable for irradiation with the electron beam e, a position suitable for irradiation with the ion beam i, or another position. In controlling such a position, for example, X SEM Rotation in a plane perpendicular to the axis (Rocking), Y SEM Rotation (Tilt) and Z in a plane perpendicular to the axis SEM Rotation takes place in a plane perpendicular to the axis.

[0016] An electron beam e is irradiated onto a sample S from an electron beam column 2. An ion beam i is irradiated from an ion beam column 4. An irradiation axis A1 of the electron beam e from the electron beam column 2 and an irradiation axis A2 of the ion beam i from the ion beam column 4 are arranged to intersect with each other at a predetermined angle on the surface of the sample S, for example. Here, the predetermined angle is, for example, greater than 50 degrees and less than 60 degrees. However, the predetermined angle is not particularly limited to this.

[0017] The electron beam control unit 22 controls the electron beam column 2. The FIB control unit 20 controls the ion beam column 4.

[0018] The secondary electron detector 6 detects secondary electrons generated from the sample S due to irradiation with the electron beam e or ion beam i.

[0019] The image forming unit 24 forms an electron microscope image using a signal for scanning the electron beam e sent from the electron beam control unit 22 to the electron beam column 2 and a signal of secondary electrons detected by the secondary electron detector 6. The display unit 34 can, for example, display the electron microscope image.

[0020] The image forming unit 24 forms a SIM image using a signal for scanning the ion beam i sent from the FIB control unit 20 to the ion beam column 4 and a signal of secondary electrons detected by the secondary electron detector 6. The display unit 34 can display, for example, the SIM image.

[0021] The display unit 34 is, for example, a display device such as a liquid crystal monitor.

[0022] For example, an operator inputs conditions related to the control of the focused ion beam device 100 into the input unit 32. The input unit 32 transmits the input information to the control unit 30. The input unit 32 is, for example, a keyboard connected to a computer. Note that the input unit 32 may also be, for example, a semiconductor memory or the like in which the conditions related to the control of the focused ion beam device 100 are stored.

[0023] The control unit 30 can control the FIB control unit 20, the electron beam control unit 22, the image formation unit 24, the sample holder control unit 28, the input unit 32, and the display unit 34. The control unit 30, the FIB control unit 20, the electron beam control unit 22, the image formation unit 24, and the sample holder control unit 28 are, for example, electronic circuits. The control unit 30, the FIB control unit 20, the electron beam control unit 22, the image formation unit 24, and the sample holder control unit 28 are, for example, computers configured by a combination of hardware such as an arithmetic circuit and software such as a program.

[0024] FIG. 2 is a schematic diagram showing an example of a diaphragm for the electron beam e used in the focused ion beam device 100 of this embodiment.

[0025] FIG. 3 is a schematic diagram showing the relationship between the focal depth of an SEM and an SIM image.

[0026] As an example of a comparative example of this embodiment, consider the case where a sample S is observed using a small aperture (single aperture (small)) and an electron beam e (focused beam) with a small convergence angle, as shown on the right side of FIG. 2 . In this case, the depth of field (DOF) of the SEM Δz is very deep, on the order of several μm. This makes it difficult to recognize changes in the depth of the sample S. Here, as shown in FIG. 3 , when the angle between the irradiation axis A1 of the electron beam e and the irradiation axis A2 of the ion beam i is θ, the shift in the lateral direction of the SIM image (the direction perpendicular to the irradiation axis A2 of the ion beam) can be expressed as Δz·sinθ. Therefore, when Δz is large, it becomes difficult to process the sample S using the ion beam i.

[0027] As an example of a comparative example of this embodiment, consider a case where a large aperture (single-hole diaphragm (large)) is used to irradiate an electron beam e (focused beam) with a large convergence angle, as shown in the center of FIG. 2, in order to increase the depth resolution. This reduces the beam's depth-wise spread at the focal position, thereby increasing the lateral resolution of the SIM image. Furthermore, since the electron beam e becomes thicker even when it is slightly shifted from the focal position, sensitivity to out-of-focus can be increased. The depth of focus is small, on the order of several hundred nanometers.

[0028] In this embodiment, a hollow cone beam using an annular diaphragm is used, as shown on the left side of Fig. 2. This corresponds to the case where only the outer electron beam e is extracted from the electron beam e formed using a large aperture, as shown in the center of Fig. 3, without using the inner electron beam e. As a result, since the inner electron beam e, which was a factor in widening the depth of focus, is not used, it is possible to make the depth of focus shallow, for example, to 10 nm or less (about a few nm).

[0029] Furthermore, it is preferable that the focal depth e of the electron beam is shallower than the thickness of the sample.

[0030] FIG. 4 is a schematic diagram showing an example of an aperture in a plane perpendicular to the plane through which the electron beam e passes, which is used to make the focal depth shallow in the electron beam lens barrel 2 of this embodiment.

[0031] 4(a) and (b) show an annular aperture 12, which is an example of a device for forming a hollow cone beam in an embodiment. The annular aperture 12 includes a plate portion 12a on the outer periphery, a central portion 12b on the inner periphery, and multiple bridges 12c connecting the plate portion 12a and the central portion 12b. When an electron beam e is irradiated onto the annular aperture 12 from the Z-axis direction, the electron beam e passes through the plate portion 12a, the central portion 12b, and an opening (gap) 12d where there are no bridges 12c. This blocks the central portion of the conical beam, forming a hollow cone beam. The number and arrangement of the bridges 12c are not limited to those shown in the figure and can be changed as appropriate.

[0032] 4(c) and (d) show a block-equipped single-aperture diaphragm 13 for forming a pseudo-hollow cone beam. The block-equipped single-aperture diaphragm 13 includes a single-aperture diaphragm 13a and a block 13c. The single-aperture diaphragm 13a has an aperture 13b. An H-shaped block 13c is provided above the aperture 13b of the single-aperture diaphragm 13a. The block 13c has a center portion 13d that is smaller than the aperture 13b, and support portions 13e that are provided on both sides of the center portion 13b and are larger than the aperture 13b. As a result, when an electron beam e is irradiated onto the block-equipped single-aperture diaphragm 13 from the Z-axis direction, the electron beam e passes through the region of the aperture 13b that is not blocked by the block 13c. This allows only the portions of the irradiated conical beam that correspond to the multiple apertures (gaps) to pass through, forming a pseudo-hollow cone beam without a center portion.

[0033] The shape of the aperture that can be preferably used in this embodiment is not limited to the above.

[0034] FIG. 5 is a flowchart of a control method for the focused ion beam apparatus of this embodiment.

[0035] First, inside the sample chamber (not shown in FIG. 1), scanning points (SEM coordinates: X in FIG. 1) of the electron beam e are determined around the cross point (CP) where the irradiation axis A1 of the electron beam e and the irradiation axis A2 of the ion beam i intersect. SEM and Y SEM ) and the focusing distance of the electron beam e (SEM focal length: Z SEM The actual workspace (first space) is defined by the focus. The size of the actual workspace is, for example, X SEM Direction Y SEM Direction・Z SEM The actual working space is defined by the control unit 30, for example.

[0036] It is preferable to use the sample holder 8 to position the surface of the sample S in the area where the irradiation axis A1 of the electron beam column 2 and the irradiation axis A2 of the ion beam column intersect.

[0037] Furthermore, when defining the actual working space defined by the scanning point and focal distance of the electron beam e, it is preferable to correct the irradiation position of the ion beam i by irradiating the surface of the sample with the ion beam i.

[0038] Next, the sample holder 8 is controlled by, for example, the sample holder control unit 28 or the control unit 30 to control (change) the attitude of the sample S to a position suitable for observing the shape of the sample S using the electron beam e.

[0039] Next, the electron beam column 2 is used to irradiate the sample S with an electron beam e. Then, an electron microscope image of the sample S is acquired using the image forming unit 24. Furthermore, the attitude of the sample S is controlled (changed) and an electron microscope image of the sample S is acquired. In this way, multiple electron microscope images of the sample S are acquired (S2 in FIG. 5).

[0040] Typically, processing of the sample S using an FIB is performed while checking the shape of the sample S using an electron microscope. After acquiring and checking an electron microscope image, if it is determined that processing of the sample S is complete (S4 in FIG. 5), the sample S is analyzed using, for example, a TEM (S10 in FIG. 5).

[0041] If the processing of the sample S is not complete, a three-dimensional model including real-space information of the sample S is then created based on the multiple acquired electron microscope images (S6 in FIG. 5). The creation of such a three-dimensional model is performed, for example, by the control unit 30. Note that a computer configured by a combination of hardware such as electronic circuits and arithmetic circuits and software such as programs, such as a "three-dimensional model creation unit," may also be used, connected to the control unit 30.

[0042] By comparing the secondary electron intensities of multiple electron microscope images in this manner, the secondary electron intensities can be used to understand the relative height and lateral relationships of the sample S. In other words, the three-dimensional shape of the sample S, including information on the actual working space (real space), can be understood.

[0043] Next, the created 3D model is displayed in a virtual space (VR (Virtual Reality) space, second space). Here, the virtual space is a space that has, for example, X-axis, Y-axis, and Z-axis directions, just like the real working space. For example, the X-axis, Y-axis, and Z-axis directions of the virtual space are the same as those of the real working space. SEM Axial direction Y SEM Axial direction・Z SEM The created 3D model of the specimen S can be placed in the virtual space at the same position as the specimen S in the actual working space.

[0044] Here, when creating a three-dimensional model of the sample S that includes real-space information, it is preferable to use a feature point P of the sample S. For example, a feature point is a portion of the sample S, such as the edge of the sample S, whose shape is relatively easy to understand and which is not directly related to the observation area. Using such feature points makes it easier to grasp the shape of the sample S. Furthermore, it also makes it easier to place the created three-dimensional model of the sample S in the virtual space at the same position as the sample S in the actual working space. Figure 6 is a schematic diagram showing an example of a three-dimensional model that includes real-space information of the sample S. Note that Figure 6 also shows a location in the three-dimensional model that corresponds to the sample holder 8, a location in the three-dimensional model that corresponds to the feature point P, and a location in the three-dimensional model that corresponds to the sample S.

[0045] For example, the created three-dimensional model may be displayed on the display unit .

[0046] Next, the ion beam i is used to process the sample S. First, the sample holder control unit 28 is used to change the attitude of the sample S, and the attitude is controlled to be suitable for processing with the ion beam i.

[0047] Next, a two-dimensional image of the surface of the sample S when viewed from the irradiation axis A2 of the ion beam i is acquired from the above three-dimensional model.

[0048] Next, a predetermined range to be irradiated with the ion beam is determined using a two-dimensional image of the surface of the sample S. Here, it is preferable to control the sample holder 8 so that the focal point of the ion beam is positioned on the surface of the sample defined by the predetermined range.

[0049] Next, the sample S is processed by irradiating a predetermined area with an ion beam (S8 in FIG. 5). Note that the processing of the sample S may be repeated several times, for example, through "rough processing," "shaping," and "finishing." In this case, the steps from S2 to S8 in FIG. 5 may be repeated several times.

[0050] In other words, in the focused ion beam device and the control method for the focused ion beam device of this embodiment, the sample S is processed using the three-dimensional model displayed in the virtual section instead of the SIM image.

[0051] Next, the effects of the control method for the focused ion beam apparatus of this embodiment will be described.

[0052] When processing using ion beam i, a predetermined range (processing frame) to be irradiated with ion beam i is set on the surface of sample S, and then processing is performed. Here, in order to set the predetermined range (processing frame) to be irradiated with ion beam i on the surface of sample S, observation of the surface of sample S is required. Generally, the resolution of SIM images is lower than that of SEM images. Therefore, when observing sample S, the insufficient resolution of the SIM images can make it difficult to recognize the shape.

[0053] In particular, when observing the sample S using an SIM image in order to perform finish processing of the sample S, the ion beam i is irradiated at a low acceleration voltage in order to suppress processing damage to the sample S due to irradiation with the ion beam i. However, the resolution of the SIM image acquired using the ion beam i at a low acceleration voltage is low. This makes it difficult to recognize the sample S, and there are problems in that it is difficult to set the predetermined range (processing frame) to irradiate with the ion beam i.

[0054] Furthermore, as described above, since it is difficult to set a predetermined range (processing frame) for ion beam irradiation, the sample S has sometimes been prepared by repeating short-term ion beam processing and observation using SIM images, which poses the problem of a long preparation time for the sample S.

[0055] Therefore, in the control method of the focused ion beam device of this embodiment, a three-dimensional model including real-space information of the sample S is created using a high-resolution electron microscope image. Then, processing using the ion beam i is performed based on this three-dimensional model. Specifically, a two-dimensional image of the surface of the sample S when viewed from the irradiation axis A2 of the ion beam i is obtained from the three-dimensional model. Since it is based on a high-resolution electron microscope image, the sample S can be processed with high precision. Furthermore, processing damage to the sample S caused by ion beam irradiation during SIM image observation can be suppressed. Therefore, it is possible to provide a focused ion beam device and a control method thereof that can easily process samples.

[0056] Here, by using an electron beam e with a shallow focal depth, the focal depth can be made shallow, for example, to 10 nm or less (several nm), as described above. This allows for increased resolution in the depth direction. For example, by passing the electron beam e through an annular aperture to form a hollow cone beam, an electron beam e with a focal depth of, for example, 10 nm or less can be formed. Alternatively, the electron beam e may be passed through multiple apertures.

[0057] Furthermore, it is preferable that the focal depth of the electron beam e is shallower than the thickness of the sample S. If the focal depth of the electron beam e is deeper than the thickness of the sample S, the resolution of the SEM image in the depth direction will be too low compared to the thickness of the sample S, making it difficult to process the sample S in the depth direction.

[0058] It is preferable to control the sample holder 8 so that the focal point of the ion beam is positioned on the surface of the sample defined by a predetermined range, since this allows for accurate processing.

[0059] Furthermore, it is preferable to use the sample holder 8 to position the surface of the sample S in the region where the irradiation axis A1 of the electron beam column 2 and the irradiation axis A2 of the ion beam column 4 intersect. This is because if the surface of the sample S is not positioned in the region where the irradiation axis A1 of the electron beam column 2 and the irradiation axis A2 of the ion beam column 4 intersect, there is a tendency for a misalignment to occur between the location where the ion beam is irradiated and the two-dimensional image of the sample S obtained from the three-dimensional model when viewed from the irradiation axis A2 of the ion beam, making it difficult to perform processing with high precision.

[0060] Furthermore, when defining the real working space defined by the scanning point and focusing distance of the electron beam e, it is preferable to correct the ion beam irradiation position by irradiating the surface of the sample with an ion beam, in order to prevent misalignment, for example, on the order of nanometers, between the sample S in the real working space and the three-dimensional model of the sample in the virtual space.

[0061] According to the focused ion beam apparatus and the control method thereof of this embodiment, it is possible to provide a focused ion beam apparatus and a control method thereof that can easily process a sample.

[0062] (Second embodiment) The focused ion beam apparatus and control method thereof of this embodiment differ from the focused ion beam apparatus and control method thereof of the first embodiment in that the sample S is rotatable within a plane perpendicular to a plane including the irradiation axis A1 of the electron beam e and the irradiation axis A2 of the ion beam i. Here, a description of the same content as in the first embodiment will be omitted.

[0063] 7 to 9 are schematic diagrams showing the sample holder 8 used in this embodiment. The sample holder 8 has a stub 8a, a mount 8b, and an FIB grid 8c. As shown in FIG. 8(b), the FIB grid 8c is fixed to the mount 8b. As shown in FIG. 8(c), the sample S is fixed to the tip of the FIB grid 8c. The sample holder 8 has an X SEM axis and Z SEMThe FIB grid 8c can rotate within a plane including the axis. In Fig. 7(a), a sample S (not shown) fixed to the FIB grid 8c is arranged along the irradiation axis A1 of the electron beam e. In Fig. 7(b), a sample S (not shown) fixed to the FIB grid 8c is arranged along the irradiation axis A2 of the ion beam i.

[0064] For example, as shown in FIG. 8(a), stub 8a has a semi-cylindrical gap. A semi-cylindrical portion of mount 8b is fitted into this gap. As shown in FIG. 9, mount 8b is fixed by, for example, leaf spring 8a2. Also, as shown in FIG. 9, mount 8b can be rotated by the expansion and contraction of piezoelectric element 8a1 in the vertical direction. Furthermore, for example, fastener 8a3 is provided to position mount 8b when piezoelectric element 8a1 returns to its original expansion and contraction state.

[0065] By using the sample holder 8 used in this embodiment, it becomes easy to acquire a plurality of electron microscope images in different observation directions, which improves the practicality of processing the sample S using a three-dimensional model.

[0066] The focused ion beam apparatus and the control method thereof according to this embodiment also make it possible to provide a focused ion beam apparatus and a control method thereof that can easily process a sample.

[0067] Although several embodiments and examples of the present invention have been described, these embodiments and examples are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the inventions and their equivalents as defined in the claims. [Explanation of symbols]

[0068] 2: Electron beam tube 4: Ion beam tube 6: Secondary electron detector 8: Sample holder 10: Secondary ion detector 12, 13: Aperture 20: FIB control section 22: Electron beam control unit 24: Electron microscope image acquisition unit 26: SIM image acquisition unit 28: Sample holder control unit 30: Control unit 32: Input section 34: Display section 100: Focused ion beam device e: electron beam A1: Electron beam irradiation axis A2: Ion beam irradiation axis i: ion beam P: feature point S: Sample

Claims

1. an electron beam column for irradiating an electron beam having a shallow focal depth onto a sample; an ion beam column for processing the sample by irradiating the sample with an ion beam; a detector for detecting electrons generated from the sample; a sample holder that holds the sample and is capable of tilting the sample with respect to the electron beam and the ion beam; defining an actual working space defined by a scanning point of the electron beam and a focal length of the electron beam; irradiating the sample with the electron beam using the electron beam column, and acquiring a plurality of electron microscope images of the sample in different observation directions; creating a three-dimensional model including real space information of the sample based on the plurality of electron microscope images; The posture of the sample is changed in accordance with the movement of the sample holder. obtaining a two-dimensional image of the sample from the three-dimensional model as viewed from the irradiation axis of the ion beam; determining a predetermined range to be irradiated with the ion beam using the two-dimensional image; a control unit that processes the sample by irradiating the predetermined area with the ion beam using the ion beam column; A focused ion beam device comprising:

2. creating the three-dimensional model including the real space information of the sample based on the plurality of electron microscope images, and then displaying the three-dimensional model in a virtual space before changing the attitude of the sample in accordance with the operation of the sample holder; 2. The focused ion beam device according to claim 1.

3. The control unit The sample holder operates to change the sample's posture, controlling the sample holder so that a focal point of the ion beam is positioned on a surface of the sample defined by the predetermined range; The focused ion beam device according to claim 1 .

4. The control unit When the actual working space is defined by the scanning point and the focusing distance of the electron beam, correcting the irradiation position of the ion beam by irradiating the surface of the sample with the ion beam using the ion beam column; The focused ion beam device according to claim 1 .

5. the electron beam is a hollow cone beam; 2. The focused ion beam device according to claim 1.

6. the electron beam column has a plurality of openings through which the electron beam passes; 2. The focused ion beam device according to claim 1.

7. In the direction of irradiation of the electron beam, the focal depth of the electron beam is shallower than the thickness of the sample.

2. The focused ion beam device according to claim 1.

8. an electron beam column for irradiating an electron beam having a shallow focal depth onto a sample; an ion beam column for processing the sample by irradiating the sample with an ion beam; a detector for detecting electrons generated from the sample; a sample holder that holds the sample and is capable of tilting the sample with respect to the electron beam and the ion beam; Using defining an actual working space defined by a scanning point of the electron beam and a focal length of the electron beam; irradiating the sample with the electron beam using the electron beam column, and acquiring a plurality of electron microscope images of the sample in different observation directions; creating a three-dimensional model including real space information of the sample based on the plurality of electron microscope images; The posture of the sample is changed in accordance with the movement of the sample holder. obtaining a two-dimensional image of the sample from the three-dimensional model as viewed from the irradiation axis of the ion beam; determining a predetermined range to be irradiated with the ion beam using the two-dimensional image; irradiating the predetermined area with the ion beam using the ion beam column to process the sample; A method for controlling a focused ion beam device.

9. creating the three-dimensional model including the real space information of the sample based on the plurality of electron microscope images, and then displaying the three-dimensional model in a virtual space before changing the attitude of the sample in accordance with the operation of the sample holder; 9. The method for controlling a focused ion beam device according to claim 8.

Images