Charged particle beam device

Abstract

A charged particle beam device is provided. Fluctuation of an irradiation position of a charged particle beam can be suppressed by appropriately correcting a positional shift due to rotation of a sample. A charged particle beam device (10) has a converging ion beam lens barrel (17), a sample holder (12), a stage (31) that supports the sample holder (12), a fixed portion rotation mechanism, a stage drive mechanism (33), and a control device (25). The sample holder (12) has a fixed portion that holds a sample (P). The fixed portion rotation mechanism rotates the fixed portion around each of a first rotation axis and a second rotation axis. The stage drive mechanism (33) three-dimensionally translates and rotates the stage (31) around a third rotation axis. The control device (25) acquires a correction value that corrects fluctuation of a position of a rotation center for rotation around at least any one of the first rotation axis, the second rotation axis, and the third rotation axis. The control device (25) translates the stage (31) in accordance with the correction value.

Description

TECHNICAL FIELD

[0001] The present application relates to a charged particle beam device. BACKGROUND

[0002] Conventionally, a charged particle beam device is known in which a sample is rotated around a plurality of rotation axes in order to stereoscopically process or observe a sample by irradiating a charged particle beam such as a convergent ion beam or an electron beam, and thereby change the incident angle of the charged particle beam (see, for example, Patent Literature 1).

[0003] Patent Literature 1: Japanese Patent Application Publication No. 2016-72089

[0004] In addition, in the above-described charged particle beam device, for example, due to the mechanical accuracy of the rotation mechanism of each rotation axis and the intersection thereof, the rotation center of rotation around each rotation axis sometimes fluctuates. Fluctuation of the rotation center causes fluctuation of the irradiation position of the charged particle beam, and thus the desired processing position or observation position in the sample can fluctuate. SUMMARY

[0005] An object of the present application is to provide a charged particle beam device capable of suppressing fluctuation of the irradiation position of a charged particle beam by appropriately correcting position shift due to rotation of a sample.

[0006] To solve the above-described problem, the charged particle beam device of the present application has: a charged particle beam barrel that irradiates a charged particle beam to a sample; a sample holder that has a fixing portion that fixes the sample; a stage that supports the sample holder; a fixing portion rotation mechanism that rotates the fixing portion around each of a first rotation axis and a second rotation axis independently with respect to the stage, the second rotation axis being parallel to a direction orthogonal to the first rotation axis; a stage drive mechanism that three-dimensionally translates the stage and the sample holder as a unit and rotates the stage around a third rotation axis; and a processing device that acquires a correction value that corrects fluctuation of the position of the rotation center of rotation around at least any one of the first rotation axis, the second rotation axis, and the third rotation axis, and corrects the irradiation position of the charged particle beam on the sample by translating the stage according to the correction value.

[0007] In the above-described structure, it can also be that the positions of the rotation center before and after rotation around at least any one of the first rotation axis, the second rotation axis, and the third rotation axis are set as a pre-rotation position and a post-rotation position, and the vectors of the pre-rotation position with respect to the rotation reference positions of the first rotation axis, the second rotation axis, and the third rotation axis, and the vectors of the post-rotation position with respect to the rotation reference positions of the first rotation axis, the second rotation axis, and the third rotation axis are synthesized, thereby obtaining the correction value.

[0008] In the above configuration, the rotation center can be caused to change in position on a prescribed closed curve to obtain the correction value.

[0009] In the above configuration, the closed curve can be an ellipse.

[0010] In the above configuration, the charged particle beam device can have a storage section that stores table data showing a correspondence between a rotation angle of each of the first, second, and third rotation axes and the correction value, and the processing device obtains the correction value from the table data.

[0011] In the above configuration, the processing device can correct a geometric positional shift of the sample with respect to an irradiation reference position set with respect to the fixed section, in addition to the correction of the irradiation position with respect to rotation around at least any one of the first, second, and third rotation axes.

[0012] In the above configuration, in a case where the rotation around at least any one of the first, second, and third rotation axes is performed during irradiation of the charged particle beam to the sample, the processing device can correct the irradiation position after the rotation is performed.

[0013] In the above configuration, the stage drive mechanism can tilt the stage and the sample holder integrally around a tilt axis that is on a coaxial line on which the position of the rotation center does not change, in addition to the translation and the rotation around the third rotation axis.

[0014] Inventive Effects

[0015] According to the present application, the processing device that corrects the change in position of the rotation center of the rotation axis related to the rotation of the sample is provided, and thus the change in irradiation position of the charged particle beam can be suppressed. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 FIG. 1 is a diagram showing the configuration of a charged particle beam device in an embodiment of the present application.

[0017] Figure 2 FIG. 2 is a diagram showing the configuration of a control device of a charged particle beam device in an embodiment of the present application.

[0018] Figure 3 FIG. 3 is a diagram schematically showing the configuration of a sample holder of a charged particle beam device in an embodiment of the present application.

[0019] Figure 4 is a detailed view Figure 3 of the structure of the sample holder shown.

[0020] Figure 5 is a view schematically showing rotation of a stage and a fixing portion of a charged particle beam device in an embodiment of the present application.

[0021] Figure 6 is a view showing a variation example of a rotation center of rotation of a fixing portion of a sample holder about an S-axis in an embodiment of the present application in an X-Y plane.

[0022] Figure 7 is a view showing a variation example of a rotation center of rotation of a fixing portion of a sample holder about an S-axis in an embodiment of the present application in a Y-Z plane.

[0023] Figure 8 is a view showing a variation example of a rotation center of rotation of a fixing portion of a sample holder about an F-axis in an embodiment of the present application in an X-Y plane.

[0024] Figure 9 is a view showing a variation example of a rotation center of rotation of a fixing portion of a sample holder about an F-axis in an embodiment of the present application in a Y-Z plane.

[0025] Figure 10 is a view showing examples before and after rotation about each of the first, second, and third axes (F-axis, S-axis, and R-axis) in an embodiment of the present application.

[0026] Figure 11 is a flowchart showing an example of operation of a charged particle beam device in an embodiment of the present application.

[0027] Explanation of Reference Numerals

[0028] 10: charged particle beam device; 11: sample chamber; 12: sample holder; 13: sample stage; 15: electron beam column (charged particle beam column); 17: convergent ion beam column (charged particle beam column); 19: gas ion beam column (charged particle beam column); 25: control device (processing device); 31: stage; 33: stage drive mechanism; 47: storage portion; 61: base; 62: first support portion; 63: swivel stage; 64: second support portion; 65: tilt stage; 66: fixing portion; 67: fixing portion rotation mechanism. DETAILED DESCRIPTION

[0029] Embodiments of a charged particle beam device of the present application will be described below with reference to the accompanying drawings.

[0030] (Charged Particle Beam Device)

[0031] Figure 1 is a view showing a structure of a charged particle beam device 10 in an embodiment. Figure 2 is a view showing a structure of a control device 25 of the charged particle beam device 10.

[0032] As shown in Figure 1 , the charged particle beam device 10 has a specimen chamber 11, a specimen holder 12, a specimen stage 13, an electron beam column 15 fixed to the specimen chamber 11, a convergent ion beam column 17, and a gas ion beam column 19.

[0033] The charged particle beam device 10 has, for example, a secondary charged particle detector 21 as a detector fixed to the specimen chamber 11. The charged particle beam device 10 has a gas supply part 23 that supplies a gas to a surface of a specimen P. The charged particle beam device 10 has a control device 25 that comprehensively controls an operation of the charged particle beam device 10 outside the specimen chamber 11, and an input device 27 and a display device 29 connected to the control device 25.

[0034] Further, hereinafter, each axis direction of an X axis, a Y axis, and a Z axis orthogonal to each other in a three-dimensional space is a direction parallel to each axis. For example, the Z axis direction is parallel to an up-down direction (for example, a vertical direction, etc.) of the charged particle beam device 10. The X axis direction and the Y axis direction are parallel to a reference plane (for example, a horizontal plane, etc.) orthogonal to the up-down direction of the charged particle beam device 10.

[0035] The specimen chamber 11 is formed of a pressure-resistant case of a gas-tight structure capable of maintaining a desired reduced pressure state. The specimen chamber 11 can be exhausted by an exhaust device (omitted from the drawing) until the inside becomes the desired reduced pressure state.

[0036] The specimen holder 12 holds the specimen P. The specimen holder 12 rotates the specimen P around each axis of a prescribed first rotation axis (F axis) and a second rotation axis (S axis) at an appropriate angle.

[0037] The specimen holder 12 in the embodiment is described later.

[0038] The specimen stage 13 is disposed inside the specimen chamber 11. The specimen stage 13 has a stage 31 that supports the specimen holder 12, and a stage drive mechanism 33 that three-dimensionally translates and rotates the stage 31 and the specimen holder 12 integrally.

[0039] The stage drive mechanism 33 has, for example, three translation mechanisms (omitted from the drawing) that translate the stage 31 along each axis direction of the X axis, the Y axis, and the Z axis. As Figure 2As shown, the stage drive mechanism 33 has, for example, two rotation mechanisms (omitted from illustration) that rotate the stage 31 at a proper angle about each of a prescribed third rotation axis (R axis) and a tilt axis (T axis). The third rotation axis (R axis) is, for example, set relative to the stage 31 so as to be parallel to the up-down direction of the charged particle beam device 10 in a case where the stage 31 is in a prescribed reference position about the tilt axis (T axis). The tilt axis (T axis) is, for example, parallel to a direction orthogonal to the up-down direction of the charged particle beam device 10. The stage drive mechanism 33 is controlled by control signals output from the control device 25 in accordance with the operation mode of the charged particle beam device 10 or the like.

[0040] The electron beam column 15 irradiates an electron beam (EB) to an irradiation target within a prescribed irradiation region inside the sample chamber 11. The electron beam column 15 has, for example, an exit end portion 15a (see Fig. 2) of the electron beam facing the stage 31 in a first tilt direction tilted at a prescribed angle with respect to the up-down direction of the charged particle beam device 10. The electron beam column 15 is fixed to the sample chamber 11 in a manner such that an optical axis 15b of the electron beam is parallel to the first tilt direction. Figure 1 ) in a first tilt direction tilted at a prescribed angle with respect to the up-down direction of the charged particle beam device 10. The electron beam column 15 is fixed to the sample chamber 11 in a manner such that an optical axis 15b of the electron beam is parallel to the first tilt direction.

[0041] The electron beam column 15 has an electron source that generates electrons, and an electron optical system that converges and deflects the electrons emitted from the electron source. The electron optical system has, for example, electromagnetic lenses and deflectors, and the like. The electron source and the electron optical system are controlled by control signals output from the control device 25 in accordance with the irradiation position and irradiation conditions of the electron beam, and the like.

[0042] The convergent ion beam column 17 irradiates a convergent ion beam (FIB) to an irradiation target within a prescribed irradiation region inside the sample chamber 11. The convergent ion beam column 17 has, for example, an exit end portion 17a (see Fig. 2) of the convergent ion beam facing the stage 31 in the up-down direction of the charged particle beam device 10. The convergent ion beam column 17 is fixed to the sample chamber 11 in a manner such that an optical axis 17b of the convergent ion beam is parallel to the up-down direction. Figure 1 ) in a first tilt direction tilted at a prescribed angle with respect to the up-down direction of the charged particle beam device 10. The electron beam column 15 is fixed to the sample chamber 11 in a manner such that an optical axis 15b of the electron beam is parallel to the first tilt direction.

[0043] The convergent ion beam column 17 has an ion source that generates ions, and an ion optical system that converges and deflects the ions emitted from the ion source. The ion optical system has, for example, a first electrostatic lens such as a condenser lens, an electrostatic deflector, a second electrostatic lens such as an objective lens, and the like. The ion source and the ion optical system are controlled by control signals output from the control device 25 in accordance with the irradiation position and irradiation conditions of the convergent ion beam, and the like. The ion source is, for example, a liquid metal ion source using liquid gallium or the like, a plasma type ion source, a gas electric field ionization type ion source, and the like.

[0044] The gas ion beam column 19 irradiates a gas ion beam (GB) to an irradiation target in a prescribed irradiation region inside the sample chamber 11. The gas ion beam column 19, for example, has an exit end portion 19a (see FIG. 2) of the gas ion beam facing the stage 31 in a second oblique direction that is oblique to the up-down direction of the charged particle beam device 10 by a prescribed angle, which is different from the oblique direction of the electron beam column 15. The gas ion beam column 19 is fixed to the sample chamber 11 in such a manner that an optical axis 19b of the gas ion beam is parallel to the second oblique direction. Figure 1 ) in a second oblique direction that is oblique to the up-down direction of the charged particle beam device 10 by a prescribed angle, which is different from the oblique direction of the electron beam column 15. The gas ion beam column 19 is fixed to the sample chamber 11 in such a manner that an optical axis 19b of the gas ion beam is parallel to the second oblique direction.

[0045] The gas ion beam column 19 has an ion source that generates gas ions, and an ion optical system that converges and deflects the gas ions that are extracted from the ion source. The ion optical system has, for example, a first electrostatic lens such as a condenser lens, an electrostatic deflector, a second electrostatic lens such as an objective lens, and the like. The ion source and the ion optical system are controlled by control signals that are output from the control device 25 in accordance with the irradiation position and the irradiation conditions of the gas ion beam, and the like. The ion source is, for example, a PIG (Penning Ionization Gauge) type ion source or the like that generates ions of a rare gas such as argon (Ar) gas or another gas such as oxygen gas.

[0046] The optical axis 15b of the electron beam column 15, the optical axis 17b of the convergent ion beam column 17, and the optical axis 19b of the gas ion beam column 19, for example, intersect at a prescribed position above the sample stage 13.

[0047] In addition, the configurations of the electron beam column 15, the convergent ion beam column 17, and the gas ion beam column 19 with respect to each other can be appropriately exchanged. For example, the electron beam column 15 or the gas ion beam column 19 can also be configured in the up-down direction, and the convergent ion beam column 17 can be configured in an oblique direction that is oblique to the up-down direction.

[0048] The charged particle beam device 10 performs scanning while the convergent ion beam or the gas ion beam is irradiated to the surface of the irradiation target, whereby it is possible to perform imaging of the irradiated portion, various processes based on sputtering (excavation and finishing processes, and the like), formation of a deposited film, and the like. The charged particle beam device 10 can perform processing to form the sample P into a sample piece (for example, a thin piece sample and a needle-shaped sample, and the like) that is used for transmission observation by a transmission electron microscope, and can perform processing to form the sample P into an analysis sample piece or the like that is used for analysis by an electron beam. The charged particle beam device 10 can perform processing to form a sample piece that is mounted on a sample piece holder into a thin film of a desired thickness that is suitable for transmission observation by a transmission electron microscope. The charged particle beam device 10 can perform observation of the surface of the irradiation target by irradiating the convergent ion beam, the gas ion beam, or the electron beam to the surface of the irradiation target such as the sample P, the sample piece, and a probe while performing scanning.

[0049] As Figure 1 shown, the secondary charged particle detector 21 detects secondary charged particles (secondary electrons and secondary ions) generated from the irradiation target due to irradiation of the convergent ion beam, the gas ion beam, or the electron beam. The secondary charged particle detector 21 is connected to the control device 25, and a detection signal output from the secondary charged particle detector 21 is sent to the control device 25.

[0050] The detectors possessed by the charged particle beam device 10 are not limited to the secondary charged particle detector 21, and other detectors can also be possessed. The other detectors are, for example, an EDS (Energy Dispersive X-ray Spectrometer) detector, a reflection electron detector, and an EBSD (Electron Back-Scattering Diffraction) detector, and the like. The EDS detector detects X-rays generated from the irradiation target due to irradiation of the electron beam. The reflection electron detector detects reflection electrons reflected from the irradiation target due to irradiation of the electron beam. The EBSD detector detects an electron back-scattering diffraction pattern generated from the irradiation target due to irradiation of the electron beam. In addition, the secondary electron detector in the secondary charged particle detector 21 that detects secondary electrons and the reflection electron detector can also be housed inside the housing of the electron beam barrel 15.

[0051] The gas supply portion 23 is fixed to the sample chamber 11. The gas supply portion 23 has a gas jet portion (nozzle) disposed in a manner facing the stage 31. The gas supply portion 23 supplies an etching gas and a deposition gas, or the like, to the irradiation target. The etching gas selectively promotes etching of the irradiation target by the convergent ion beam or the gas ion beam depending on the material of the irradiation target. The deposition gas forms a deposition film on the surface of the irradiation target by a deposit such as a metal or an insulator.

[0052] The gas supply portion 23 is controlled by a control signal output from the control device 25 depending on the operation mode of the charged particle beam device 10, or the like.

[0053] The control device 25 comprehensively controls the operation of the charged particle beam device 10, for example, depending on a signal output from the input device 27 or a signal generated by a pre-set automatic operation control process, or the like. As Figure 2 shown, the control device 25 has, for example, a sample stage control portion 41 that controls the stage drive mechanism 33 of the sample stage 13, a sample holder control portion 43 that controls a later-described fixing portion rotation mechanism 67, a control portion 45 that comprehensively controls the sample stage control portion 41 and the fixing portion rotation mechanism 67, and a storage portion 47.

[0054] The control device 25 is, for example, a software function section that functions by a processor such as a CPU (Central Processing Unit) executing a prescribed program. The software function section is an ECU (Electronic Control Unit) that has a processor such as a CPU, a ROM (Read Only Memory) that stores a program, a RAM (Random Access Memory) that temporarily stores data, and an electronic circuit such as a timer. At least a part of the control device 25 can also be an integrated circuit such as an LSI (Large Scale Integration).

[0055] As shown in FIG. 1, the input device 27 is, for example, a mouse and a keyboard that output a signal corresponding to an input operation by an operator. Figure 1

[0056] The display device 29 displays various information of the charged particle beam device 10, image data generated from a signal output from the secondary charged particle detector 21, and a screen for performing an operation such as enlargement, reduction, movement, and rotation of the image data, and the like.

[0057] (Specimen Holder)

[0058] Figure 3 is a diagram schematically showing a structure of the specimen holder 12 in the embodiment. Figure 4 is a diagram showing a structure of the specimen holder 12 in detail, and is an enlarged view of the region B shown in FIG. 1. As shown in FIG. 2, for example, the specimen holder 12 has a base 61, a pair of first support portions 62, a turntable 63, a pair of second support portions 64 (see FIG. 3), an inclined table 65, a fixing portion 66, and a fixing portion rotation mechanism 67. Figure 3 Figure 3 Figure 4

[0059] The base 61 is supported by the stage 31 of the specimen stage 13. The base 61 is positioned and fixed on the stage 31, for example, by a positioning mechanism (not shown) provided to the stage 31 or the like.

[0060] The pair of first support portions 62 is fixed to the base 61. The pair of first support portions 62 is arranged so as to face each other with a prescribed interval in a prescribed first direction D1 set with respect to the base 61. The first direction D1 is, for example, a length direction orthogonal to a thickness direction of the base 61 or the like.

[0061] ​​​​The pair of first support portions 62 have shafts 62a that support the turn table 63 so as to be rotatable. The central axis of the shafts 62a is the same as the central axis of the first rotation axis (F-axis) that is parallel to the first direction Dl. The shafts 62a of the pair of first support portions 62 protrude and extend in a direction in which they face each other in the first direction Dl.

[0062] The turn table 63 is disposed, for example, in a recess 61a formed in the surface 61A of the base 61. The turn table 63 has a pair of bearing portions 63a that are connected to the shafts 62a of the pair of first support portions 62 so as to enable the shafts 62a to rotate. The turn table 63 is supported by the pair of first support portions 62 via the pair of bearing portions 63a, and thus can rotate by a suitable angle about the first rotation axis (F-axis).

[0063] As shown in Figure 4 The pair of second support portions 64 are fixed to the turn table 63. The pair of second support portions 64 are disposed so as to face each other at a prescribed interval in a prescribed second direction D2 that is set in relation to the base 61. The second direction D2 is, for example, a short side direction that is parallel to a direction orthogonal to the first direction Dl and orthogonal to the thickness direction of the base 61.

[0064] The pair of second support portions 64 have rollers 64a and roller shafts 64b that support the tilt table 65 so as to be rotatable. The central axes of the rollers 64a and the roller shafts 64b are the same as an axis G that is parallel to the second direction D2.

[0065] The rollers 64a are connected to the end portions of the roller shafts 64b in a rotatable manner, for example, via bearings or the like. The roller shafts 64b of the pair of second support portions 64 protrude and extend in a direction in which they face each other in the second direction D2.

[0066] The tilt table 65 is disposed, for example, in a recess 63b formed in the surface 63A of the turn table 63. The outer shape of the tilt table 65 is, for example, a columnar shape having two end faces that are semicircular, obtained by cutting a portion of a cylinder along a cross section parallel to the central axis. The axis of the tilt table 65 is parallel to the second direction D2.

[0067] The tilt table 65 has guide portions 65a at both end portions in the axis direction parallel to the second direction D2, for the rollers 64a of the pair of second support portions 64. The outer shape of the guide portions 65a is, for example, a groove shape having a wall surface curved at a certain radius of curvature. The guide portions 65a have guide surfaces 65A curved at a certain radius of curvature about the second rotation axis (S-axis) and in contact with the outer peripheral surface of the rollers 64a. The rotation of the rollers 64a is guided by the guide surfaces 65A in a non-slip manner, and thus the tilt table 65 rotates about the second rotation axis (S-axis) by a suitable angle.

[0068] The tilt stage 65 has a worm wheel portion 65b at an outer peripheral portion curved between both end portions in the axial direction and around the second rotation axis (S axis), for example. A center of a pitch circle of the worm wheel portion 65b is located on an axis of the second rotation axis (S axis) together with a center of curvature of the guide surface 65A. The tilt stage 65 is applied with a rotational driving force around the second rotation axis (S axis), for example, via a worm (not shown) engaged with the worm wheel portion 65b.

[0069] The tilt stage 65 has a flat portion 65c connected to the outer peripheral portion between both end portions in the axial direction.

[0070] The fixing portion 66 fixes the sample P. The fixing portion 66 is fixed to the flat portion 65c of the tilt stage 65. The fixing portion 66 has a grid 66a on which the sample P is mounted, for example.

[0071] As shown in FIG. 6, the fixing portion rotation mechanism 67 has two rotation mechanisms (not shown) that rotate the fixing portion 66 around each of the prescribed first rotation axis (F axis) and the second rotation axis (S axis) at an appropriate angle, for example. The fixing portion rotation mechanism 67 is controlled by a control signal output from the control device 25 in accordance with an operation mode of the charged particle beam device 10 or the like. Figure 3

[0072] Next, the operation of the charged particle beam device 10 will be described.

[0073] Figure 5 FIG. 6 is a diagram schematically showing the rotation of the stage 31 of the sample stage 13 and the fixing portion 66 of the sample holder 12 of the charged particle beam device 10.

[0074] The stage drive mechanism 33 and the fixing portion rotation mechanism 67 respectively rotate the stage 31 around each of the third rotation axis (R axis) and the tilt axis (T axis) on a concentric circle in which the position of the rotation center does not change, and rotate the fixing portion 66 around each of the first rotation axis (F axis) and the second rotation axis (S axis) on a concentric circle in which the position of the rotation center does not change, in an ideal position alignment state in which mechanical precision and cross talk or the like can be ignored, for example. The stage drive mechanism 33 translates the stage 31 along each of the X axis, the Y axis, and the Z axis, for example.

[0075] The control device 25 performs a process of correcting the geometric positional deviation of the sample P and a process of correcting the positional variation of the rotation center with respect to the rotational operation of each of the stage drive mechanism 33 and the fixing portion rotation mechanism 67.

[0076] ​The geometrical positional deviation of the sample P is, for example, a geometrical positional deviation of a desired irradiation position of the sample P from a concentric position due to the mounting position of the sample P with respect to the fixing portion 66, the shape of the sample P, and the like.

[0077] The position variation of the rotation center is, for example, a position variation of the rotation center of each rotation axis and the tilt axis due to mechanical precision and cross talk, and the like.

[0078] The control device 25, for example, stores table data for correcting the position variation of the rotation center in the storage portion 47 in advance. The table data is, for example, data indicating a correspondence relationship between a rotation angle of each axis around the first rotation axis (F axis), the second rotation axis (S axis), and the third rotation axis (R axis) and a correction value. The correction value is, for example, a spatial vector related to a deviation of the rotation center of each rotation axis from a rotation reference position set as a prescribed reference for the rotation center of each rotation axis. The rotation reference position is, for example, a position of the rotation center in a case where a rotation angle around each rotation axis is a prescribed value (for example, zero, and the like). The deviation of the rotation center rotating around each axis is not affected by rotation around other axes. The control device 25, for example, refers to the table data based on information of the rotation angle of each rotation axis in a case where rotation around at least any one of the first rotation axis (F axis), the second rotation axis (S axis), and the third rotation axis (R axis) is performed, thereby acquiring a correction value. In a case where rotation around a plurality of axes is performed, the correction values of each rotation axis are added, and a final correction value is acquired. The control device 25, for example, three-dimensionally translates the stage 31 by the stage driving mechanism 33, cancels the position variation of the rotation center based on the acquired correction value, thereby correcting the irradiation position of the charged particle beam on the sample P.

[0079] Figure 6 FIG. 4 is a view illustrating an example of a variation of a rotation center of a rotation around the S axis of the fixing portion 66 of the sample holder 12 in the X-Y plane. Figure 7 FIG. 5 is a view illustrating an example of a variation of a rotation center of a rotation around the S axis of the fixing portion 66 of the sample holder 12 in the Y-Z plane. Figure 8 FIG. 6 is a view illustrating an example of a variation of a rotation center of a rotation around the F axis of the fixing portion 66 of the sample holder 12 in the X-Y plane. Figure 9 FIG. 7 is a view illustrating an example of a variation of a rotation center of a rotation around the F axis of the fixing portion 66 of the sample holder 12 in the Y-Z plane.

[0080] For example, the center of rotation of each rotation axis is caused to change in position on a prescribed closed curve in three-dimensional space, thereby obtaining the correction value of the table data. The prescribed closed curve is, for example, an ellipse. The prescribed closed curve is generated, for example, based on a plurality of measurement points (for example, at least three measurement points, etc.) obtained by measurement of the change in position of the center of rotation performed in advance on the charged particle beam device 10.

[0081] The control device 25 sets the position of the center of rotation of each rotation axis before and after rotation to a pre-rotation position and a post-rotation position, for example, with respect to rotation around at least any one of the first rotation axis (F-axis), the second rotation axis (S-axis), and the third rotation axis (R-axis). The control device 25 obtains a correction value from the table data based on the rotation angle of each rotation axis before and after rotation. The control device 25 obtains a vector of the pre-rotation position with respect to the rotation reference position (pre-rotation shift amount) from the correction value corresponding to the rotation angle of each rotation axis before rotation, and obtains a vector of the post-rotation position with respect to the rotation reference position (post-rotation shift amount) from the correction value corresponding to the rotation angle of each rotation axis after rotation. The control device 25 causes the stage drive mechanism 33 to operate using a resultant vector obtained by synthesizing the vector of the pre-rotation position and the vector of the post-rotation position as a new correction value, thereby correcting the change in position of the center of rotation.

[0082] For example, in the case where the center of rotation before rotation is not coincident with the rotation reference position, that is, in the case where the rotation angle around each rotation axis before rotation is not a prescribed value (for example, zero, etc.), it can be said that the correction by the correction value corresponding to the rotation angle before rotation is like a reset, and the correction by the correction value corresponding to the rotation angle after rotation is like a new correction after the reset.

[0083] For example, the case where the center of rotation before rotation is coincident with the rotation reference position, that is, the case where the rotation angle around each rotation axis before rotation is a prescribed value (for example, zero, etc.), corresponds to the case where the vector of the pre-rotation position in the above-mentioned resultant vector is zero. In this case, correction by the correction value corresponding to the rotation angle before rotation, that is, reset, is not needed, and correction by the correction value corresponding to the rotation angle after rotation is performed alone.

[0084] Figure 10 is a view showing an example of before and after rotation of each of the first rotation axis (F-axis), the second rotation axis (S-axis), and the third rotation axis (R-axis).

[0085] For example, in a case where the state is shifted from the first state in which the respective rotation angles of the first rotation axis (F axis), the second rotation axis (S axis), and the third rotation axis (R axis) are 0°, -30°, and 90° to a second state in which the respective rotation angles are 0°, 30°, and 180°, the direction in which the center of rotation is corrected (correction direction) changes along with the change in the respective rotation angles of the second rotation axis (S axis) and the third rotation axis (R axis). For example, in a case where the center of rotation with respect to the second rotation axis (S axis) is corrected, the correction direction in the first state is the Z axis direction and the X axis direction, and, in contrast, the correction direction in the second state is the Z axis direction and the Y axis direction. In such a case where the correction direction changes before and after rotation, a correction amount after movement is obtained by synthesizing a first correction amount that changes the first state to a rotation reference position and a second correction amount that changes the rotation reference position to the second state. For example, first, a first correction amount that makes the rotation angle of the second rotation axis (S axis) zero from the first state is obtained. Next, after reflecting rotation around the third rotation axis (R axis), a second correction amount that makes the rotation angle of the second rotation axis (S axis) change from zero to the second state is obtained. The correction amount obtained by synthesizing the first correction amount and the second correction amount is a correction amount after movement from the first state to the second state.

[0086] For example, in a case where the state is shifted from the first state in which the respective rotation angles of the first rotation axis (F axis), the second rotation axis (S axis), and the third rotation axis (R axis) are 0°, -30°, and 90° to a third state in which the respective rotation angles are -90°, 30°, and 90°, the direction in which the center of rotation is corrected (correction direction) changes along with the change in the respective rotation angles of the first rotation axis (F axis) and the second rotation axis (S axis). For example, in a case where the center of rotation with respect to the second rotation axis (S axis) is corrected, the correction direction in the first state is the Z axis direction and the X axis direction, and, in contrast, the correction direction in the third state is the X axis direction and the Y axis direction. In such a case where the correction direction changes before and after rotation, a correction amount after movement is obtained by synthesizing a first correction amount that changes the first state to a rotation reference position and a third correction amount that changes the rotation reference position to the third state. For example, first, a first correction amount that makes the rotation angle of the second rotation axis (S axis) zero from the first state is obtained. Next, after reflecting rotation around the first rotation axis (F axis), a third correction amount that makes the rotation angle of the second rotation axis (S axis) change from zero to the third state is obtained. The correction amount obtained by synthesizing the first correction amount and the third correction amount becomes a correction amount after movement from the first state to the third state.

[0087] In Figure 11In the present embodiment, as a flowchart of an operation example of the charged particle beam device 10, a process of correcting a positional variation of a rotation center of rotation around at least any one of the first rotation axis (F axis) and the second rotation axis (S axis) is shown. Also, a process of correcting a positional variation of a rotation center of rotation around at least any one of the first rotation axis (F axis), the second rotation axis (S axis), and the third rotation axis (R axis) is also the same.

[0088] First, the control device 25 initializes the total correction amount to zero (step S01). The total correction amount is a total amount of a correction amount for correcting a positional shift of the geometry of the sample P and a correction amount for correcting the positional variation of the rotation center (the above-mentioned resultant vector).

[0089] Next, the control device 25 determines whether or not there is a rotation (swing) around each of the first rotation axis (F axis) or the second rotation axis (S axis) (step S02).

[0090] In the case where the determination result is "No" (step S02: No), the control device 25 ends the process.

[0091] On the other hand, in the case where the determination result is "Yes" (step S02: Yes), the control device 25 causes the process to proceed to step S03.

[0092] Next, as a series of loop processes of step S03 to step S05, the control device 25 acquires the pre- movement shift amount with respect to each of the first rotation axis (F axis), the second rotation axis (S axis), and the third rotation axis (R axis).

[0093] For example, first, the control device 25 newly sets a value obtained by adding 1 to the value of the axis number parameter NAx at the current time point, which is an initial value of zero, as the axis number parameter NAx (step S03).

[0094] Next, the control device 25 acquires the pre-movement shift amount with respect to any one of the first rotation axis (F axis), the second rotation axis (S axis), and the third rotation axis (R axis) corresponding to the axis number parameter NAx (step S04).

[0095] Next, the control device 25 determines whether or not the axis number parameter NAx is smaller than a prescribed axis number (for example, 4) (step S05).

[0096] In the case where the determination result is "Yes" (step S05: Yes), the control device 25 returns the process to step S03.

[0097] On the other hand, in the case where the determination result is "No" (step S05: No), the control device 25 initializes the axis number parameter NAx and causes the process to proceed to step S06.

[0098] Next, as a series of loop processing of Step S06 to Step S10, the control device 25 acquires the total correction amount for each of the first rotation axis (F-axis), the second rotation axis (S-axis), and the third rotation axis (R-axis).

[0099] For example, first, the control device 25 newly sets a value obtained by adding 1 to the value of the axis number parameter NAx at the current time point, which is zero, as the axis number parameter NAx (Step S06).

[0100] Next, the control device 25 acquires the post-motion shift amount for any one of the first rotation axis (F-axis), the second rotation axis (S-axis), and the third rotation axis (R-axis) corresponding to the axis number parameter NAx (Step S07).

[0101] Next, the control device 25 acquires a correction amount for correcting the geometric positional shift of the sample P (geometric correction amount) for any one of the first rotation axis (F-axis), the second rotation axis (S-axis), and the third rotation axis (R-axis) corresponding to the axis number parameter NAx (Step S08).

[0102] Next, the control device 25 adds up the resultant vector obtained by vector synthesis of the pre-motion shift amount and the post-motion shift amount and the geometric correction amount for any one of the first rotation axis (F-axis), the second rotation axis (S-axis), and the third rotation axis (R-axis) corresponding to the axis number parameter NAx, and acquires the total correction amount (Step S09).

[0103] Next, the control device 25 determines whether the axis number parameter NAx is smaller than a prescribed number of axes (for example, 4) (Step S10).

[0104] In the case where the determination result is "Yes" (Step S10: Yes), the control device 25 returns the processing to Step S06.

[0105] On the other hand, in the case where the determination result is "No" (Step S10: No), the control device 25 advances the processing to Step S11.

[0106] Next, the control device 25 causes the stage drive mechanism 33 to operate using the total correction amount of each rotation axis, thereby correcting the geometric positional shift of the sample P and correcting the positional variation of the rotation center (Step S11). Then, the control device 25 ends the processing.

[0107] As described above, the charged particle beam device 10 of the embodiment has the control device 25 that acquires a correction value that corrects a positional variation of a rotation center of rotation around at least any one of the first rotation axis (F axis), the second rotation axis (S axis), and the third rotation axis (R axis). Thereby, it is possible to appropriately correct a positional shift due to rotation of the sample P, and to suppress a variation of an irradiation position of the charged particle beam. For example, in a case where the sample P is rotated around each rotation axis at the time of finish machining of the sample P or the like, it is also possible to maintain a state of concentricity, and to perform desired machining with high accuracy.

[0108] The control device 25 causes the stage driving mechanism 33 to act using a resultant vector obtained by synthesizing a vector of the pre-rotation position and a vector of the post-rotation position, thereby correcting the positional variation of the rotation center. Thereby, for example, in a case where only the correction value corresponding to the rotation angle is used in a state where the rotation center before rotation is not coincident with the rotation reference position, that is, in a case where only the post-moving shift amount is used without considering the pre-moving shift amount, it is not possible to appropriately correct the positional variation of the rotation center, in contrast to this, the present application makes it possible to perform appropriate and high-accuracy correction.

[0109] The control device 25 acquires a correction value obtained by causing the rotation center to have a positional variation on a prescribed closed curve (for example, an ellipse or the like), thereby making it possible to correct the positional variation of the rotation center due to mechanical accuracy of the rotation mechanism of each rotation axis and intersection or the like with high accuracy.

[0110] The control device 25 acquires the correction value from the table data generated in advance, thereby making it possible to quickly and easily correct the positional variation of the rotation center.

[0111] The control device 25 also corrects a geometrical positional shift of the sample P on the basis of correction of the positional variation of the rotation center, thereby making it possible to correct the irradiation position of the charged particle beam on the sample P with high accuracy.

[0112] (Modified Example)

[0113] Hereinafter, a modified example of the embodiment will be described.

[0114] In the above-described embodiment, the control device 25 generates a resultant vector using correction values acquired from the table data in accordance with the rotation angles of each rotation axis before and after rotation in a case where the rotation center before rotation is not coincident with the rotation reference position, but is not limited thereto.

[0115] For example, the control device 25 can also refer to table data of a resultant vector generated in advance, and acquire data of the resultant vector as a correction value for the positional variation of the rotation center.

[0116] In addition, in the above-described embodiment, in the case where the rotation around each of the rotation axes is performed during the irradiation of the charged particle beam to the sample P, the control device 25 can correct the irradiation position after the rotation is performed, or can correct the irradiation position during the rotation is performed.

[0117] In the above-described embodiment, the charged particle beam device 10 has the electron beam column 15, the convergent ion beam column 17, and the gas ion beam column 19, but is not limited thereto.

[0118] For example, the charged particle beam device 10 can also have at least any one of the electron beam column 15, the convergent ion beam column 17, and the gas ion beam column 19.

[0119] The embodiments of the present application are suggested as examples, and are not intended to limit the scope of the application. The embodiments can be implemented in other various ways, and various omissions, substitutions, and changes can be made without departing from the scope of the application. The embodiments and modifications thereof are included in the scope and spirit of the application, and are also included in the scope of the application and equivalents thereof recited in the claims.

Claims

1. A charged particle beam device, characterized in that, The charged particle beam device has: a charged particle beam column that irradiates a sample with a charged particle beam; a sample holder that has a fixing portion that fixes the sample; a stage that supports the sample holder; a fixing portion rotation mechanism that rotates the fixing portion independently of the stage about each of a first rotation axis and a second rotation axis that is parallel to a direction orthogonal to the first rotation axis; a stage drive mechanism that three-dimensionally translates the stage and the sample holder as a unit and rotates the stage about a third rotation axis; and a processing device that acquires a correction value for correcting a position of irradiation of the charged particle beam on the sample, the correction value being for correcting a position variation of a rotation center of rotation about at least any one of the first rotation axis, the second rotation axis, and the third rotation axis, sets positions of the rotation center before and after rotation about at least any one of the first rotation axis, the second rotation axis, and the third rotation axis as a pre-rotation position and a post-rotation position, and synthesizes a vector of the pre-rotation position with respect to a rotation reference position of each of the first rotation axis, the second rotation axis, and the third rotation axis and a vector of the post-rotation position with respect to the rotation reference position of each of the first rotation axis, the second rotation axis, and the third rotation axis, thereby obtaining the correction value.

2. The charged particle beam device according to claim 1, wherein the correction value is obtained by setting the rotation center to vary in position on a prescribed closed curve.

3. The charged particle beam device according to claim 2, wherein the closed curve is an ellipse.

4. The charged particle beam device according to any one of claims 1 to 3, wherein the charged particle beam device has a storage portion that stores table data that shows a correspondence between a rotation angle of each of the first rotation axis, the second rotation axis, and the third rotation axis and the correction value, the processing device acquires the correction value from the table data.

5. The charged particle beam device according to any one of claims 1 to 3, wherein the processing device corrects a geometric positional shift of the sample with respect to an irradiation reference position that is set with respect to the fixing portion in addition to correcting the irradiation position of the charged particle beam on the sample with respect to rotation about at least any one of the first rotation axis, the second rotation axis, and the third rotation axis.

6. The charged particle beam device according to any one of claims 1 to 3, wherein in a case where the rotation about at least any one of the first rotation axis, the second rotation axis, and the third rotation axis is performed during irradiation of the charged particle beam on the sample, the processing device corrects the irradiation position after rotation is performed.

7. The charged particle beam device according to any one of claims 1 to 3, wherein In addition to the translation and the rotation around the third rotation axis, the stage drive mechanism also tilts the stage and the sample holder integrally around a tilt axis which is a concentric axis whose position does not change. In addition to the translation and the rotation around the third rotation axis, the stage drive mechanism also tilts the stage and the sample holder integrally around a tilt axis which is a concentric axis whose position does not change.

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