Measurement method, adjustment method, sample processing device, and tilt angle measuring device

Abstract

To provide a measurement method capable of measuring a tilt angle of an ion beam.SOLUTION: A method for measuring a tilt angle of an ion beam in a sample processing device that processes a sample by irradiating a sample with an ion beam includes the steps of mounting a tilt angle measuring device provided with a slit on a sample stage of the sample processing device, irradiating the tilt angle measuring device with the ion beam while changing the tilt angle of the ion beam, measuring the amount of current of the ion beam having passed through the slit, and detecting the peak of the current amount of the ion beam having passed through the slit.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present invention relates to a measurement method, an adjustment method, a sample processing device, and a tilt angle measuring instrument. [Background technology]

[0002] In preparing a sample for a transmission electron microscope, a sample processing device that performs ion milling on the sample using a broad ion beam is suitable for thinning a wide area.

[0003] Patent Document 1 discloses a sample preparation device that prepares a thin-film sample for a transmission electron microscope by placing a shielding belt on the upper surface of the sample, irradiating the sample with an ion beam through the shielding belt, and ion milling the portion not shielded by the shielding belt. In the sample preparation device described in Patent Document 1, the ion gun is tilted left and right to mill alternately the front and back surfaces of the sample.

[0004] For example, when fabricating a thin film on a bulk sample, the tilt angle of the ion beam is set to about 2° to 3°. That is, when fabricating a thin film on a bulk sample, the incident angle of the ion beam with respect to the front surface of the sample and the incident angle of the ion beam with respect to the back surface of the sample are set to about 2° to 3°.

[0005] Furthermore, this type of sample processing device can use a two-stage milling method to prepare samples for cross-sectional observation of thin films formed on substrates or laminated films formed on substrates with wiring, transistors, etc. The two-stage milling method involves a primary milling step to thin the entire sample, and a secondary milling step to thin the thin film or laminated film to a thickness that can be observed with a transmission electron microscope. In the primary milling step, the tilt angle of the ion beam is set to approximately 0° to 0.5°. In the secondary milling step, the tilt angle of the ion beam is set to approximately 3° to 4°. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-193962 Summary of the Invention [Problem to be solved by the invention]

[0007] In such a sample processing device, if there is a discrepancy between the incident angle of the ion beam relative to the front surface of the sample and the incident angle of the ion beam relative to the back surface of the sample, a large difference will occur between the milling rates of the front surface and the back surface of the sample. To correct this discrepancy in the incident angle, it is necessary to adjust the tilt mechanism that tilts the ion gun.

[0008] For example, a sample is milled with the tilt angle of the ion gun fixed at 0°, and the difference in processing depth between the front and back surfaces of the sample is observed. The tilt angle of the ion gun is then adjusted so that the difference in processing depth between the front and back surfaces of the sample is reduced. This process of milling the sample and adjusting the tilt angle of the ion gun is repeated until the difference in processing depth between the front and back surfaces of the sample is eliminated. The tilt mechanism is then adjusted so that the position (tilt angle) of the ion source when the difference in processing depth between the front and back surfaces of the sample is eliminated is the center of the tilt angle range when the ion source is tilted left and right. This reduces the difference between the incident angle of the ion beam relative to the front surface of the sample and the incident angle of the ion beam relative to the back surface of the sample.

[0009] However, with this adjustment method, milling of the sample and adjustment of the tilt angle of the ion gun must be repeated until the difference in processing depth between the front and back surfaces of the sample disappears. If the tilt angle of the ion beam can be measured, the tilt mechanism can be easily adjusted. [Means for solving the problem]

[0010] One aspect of the measurement method according to the present invention is A method for measuring a tilt angle of an ion beam in a sample processing apparatus that processes a sample by irradiating the sample with an ion beam, comprising: a step of attaching a tilt angle measuring device provided with a slit to a sample stage of the sample processing device; irradiating the tilt angle measuring device with the ion beam while changing the tilt angle of the ion beam, and measuring the current amount of the ion beam that has passed through the slit; detecting a peak of the current amount of the ion beam that has passed through the slit; Includes.

[0011] Such a measurement method allows the tilt angle of the ion beam to be measured.

[0012] One aspect of the adjustment method according to the present invention is to detecting the peak by the measurement method; adjusting a tilt mechanism that tilts the ion beam based on the peak; Includes.

[0013] In this adjustment method, the tilt mechanism can be adjusted based on the measurement results of the tilt angle of the ion beam, and therefore the tilt mechanism can be easily adjusted.

[0014] One aspect of the sample processing device according to the present invention is A sample processing device that processes a sample by irradiating the sample with an ion beam, an ion source that irradiates the sample with an ion beam; a sample holder for holding the sample; a tilt angle measuring device including a slit for passing the ion beam; a tilt mechanism for tilting the ion beam with respect to the sample; a current measuring device for measuring the current amount of the ion beam that has passed through the slit; a measuring unit that detects a peak of the current amount of the ion beam that has passed through the slit when the ion beam is irradiated onto the tilt angle measuring device while changing the tilt angle of the ion beam; Includes.

[0015] In such a sample processing device, the tilt angle of the ion beam can be measured.

[0016] One aspect of the inclination angle measuring instrument according to the present invention is 1. A tilt angle measuring device for measuring a tilt angle of an ion beam in a sample processing device that processes a sample by irradiating the sample with an ion beam, comprising: It includes a slit to allow the ion beam to pass through.

[0017] In such a tilt angle measuring device, when the tilt angle of the ion beam coincides with the depth direction of the slit, the amount of current of the ion beam passing through the slit is maximized, and therefore the tilt angle of the ion beam can be measured. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a diagram showing the configuration of a sample processing device according to a first embodiment. [Figure 2] FIG. 1 is a diagram showing the configuration of a sample processing device according to a first embodiment. [Figure 3] FIG. 3 is a diagram for explaining the operation of an ion source. [Figure 4] FIG. 10 is a diagram for explaining the swinging operation of the sample. [Figure 5] FIG. 2 is a diagram schematically showing how a sample is processed by the sample processing device according to the first embodiment. [Figure 6] FIG. 10 is a diagram for explaining the operation of the ion source when the tilt angle of the ion beam is not 0° at the center of the tilt angle range of the ion source. [Figure 7] FIG. 10 is a diagram schematically showing a sample processed in a state where the angle of incidence of the ion beam on the processing surface Sb is different from the angle of incidence of the ion beam on the processing surface Sc. [Figure 8] FIG. 10 is a diagram showing a state in which the ion source tilt mechanism is adjusted so that the tilt angle of the ion beam is 0° at the center of the tilt angle range of the ion source. [Figure 9] FIG. 2 is a perspective view schematically showing a tilt angle measuring device. [Figure 10] FIG. 2 is a cross-sectional view schematically showing the tilt angle measuring device. [Figure 11]10 is a flowchart showing an example of a method for measuring the tilt angle of an ion beam. [Figure 12] FIG. 10 is a diagram for explaining a method for measuring the tilt angle of an ion beam. [Figure 13] FIG. 10 is a diagram for explaining a method for measuring the tilt angle of an ion beam. [Figure 14] FIG. 10 is a diagram for explaining a method for measuring the tilt angle of an ion beam. [Figure 15] FIG. 10 is a diagram for explaining a method for measuring the tilt angle of an ion beam. [Figure 16] FIG. 10 is a diagram for explaining a method for measuring the tilt angle of an ion beam. [Figure 17] FIG. 10 is a diagram for explaining a method for measuring the tilt angle of an ion beam. [Figure 18] FIG. 10 is a diagram for explaining a method for measuring the tilt angle of an ion beam. [Figure 19] FIG. 10 is a diagram for explaining a method for measuring the tilt angle of an ion beam. [Figure 20] FIG. 10 is a diagram for explaining a method for measuring the tilt angle of an ion beam. [Figure 21] 10 is a flowchart showing an example of a method for adjusting an ion source tilt mechanism. [Figure 22] 10 is a flowchart showing an example of processing by a measurement unit. [Figure 23] Cross-sectional SEM image of a sample processed in the sample processing device after adjusting the ion source tilt mechanism. [Figure 24] Cross-sectional SEM image of a sample processed in the sample processing device before adjusting the ion source tilt mechanism. [Figure 25] FIG. 10 is a diagram showing the configuration of a sample processing device according to a second embodiment. [Figure 26] FIG. 4 is a diagram for explaining the operation of the sample holder. [Figure 27] FIG. 10 is a diagram for explaining a method for measuring the tilt angle of an ion beam. [Figure 28] FIG. 10 is a diagram for explaining a method for measuring the tilt angle of an ion beam. [Figure 29] FIG. 10 is a diagram for explaining a method for measuring the tilt angle of an ion beam. [Figure 30]10 is a flowchart showing an example of a method for adjusting the sample holder tilt mechanism in the sample processing device according to the second embodiment. [Figure 31] FIG. 10 shows the state in which the sample holder tilt mechanism is adjusted so that the tilt angle of the ion beam is 0° at the center of the tilt angle range of the sample holder. [Figure 32] 10 is a flowchart showing an example of processing by a measurement unit. [Figure 33] FIG. 10 is a cross-sectional view schematically showing a modified example of the tilt angle measuring instrument. [Figure 34] FIG. 10 is a cross-sectional view schematically showing a modified example of the tilt angle measuring instrument. [Figure 35] 10 is a graph showing the results of measuring the tilt angle of an ion beam using a tilt angle measuring device according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0019] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. Note that the embodiments described below do not unduly limit the content of the present invention as defined in the claims. Furthermore, not all of the configurations described below are necessarily essential components of the present invention.

[0020] 1. First embodiment 1.1. Sample processing equipment First, a sample processing device according to the first embodiment will be described with reference to the drawings. Figures 1 and 2 are diagrams showing the configuration of a sample processing device 100 according to the first embodiment. Figures 1 and 2 show an X-axis, a Y-axis, and a Z-axis as three mutually orthogonal axes.

[0021] The sample processing apparatus 100 is an apparatus for irradiating an ion beam IB onto a sample S to process the sample S and prepare a sample for observation or analysis. The sample processing apparatus 100 can prepare a thin film sample that can be observed with a transmission electron microscope.

[0022] As shown in Figures 1 and 2, the sample processing device 100 includes an ion source 10, an ion source tilting mechanism 20, a sample holder 30, a shielding member 40, an illumination device 50, a camera 60, an optical system 62, a current measuring device 70, and a measurement unit 80.

[0023] The ion source 10 irradiates the sample S with an ion beam IB. The ion source 10 is attached to the top of a chamber (not shown) and irradiates the sample S housed in the chamber with the ion beam IB. The inside of the chamber is in a vacuum state. The ion source 10 is, for example, an ion gun that accelerates ions at a predetermined acceleration voltage and emits the ion beam IB.

[0024] The ion source tilting mechanism 20 tilts the ion source 10. The ion source tilting mechanism 20 oscillates the ion source 10 about an axis parallel to the X-axis as the tilt axis. Oscillation refers to a reciprocating motion within a predetermined angular range. The ion source tilting mechanism 20 tilts the ion source 10 by, for example, motor driving.

[0025] The sample holder 30 holds the sample S, as shown in Fig. 2. For example, both longitudinal ends of the sample S (in the illustrated example, the end in the +X direction and the end in the -X direction) are fixed to the sample holder 30. Although not shown, the sample processing device 100 includes a sample stage, and the sample holder 30 is attached to the sample stage. The sample S has a plate-like shape. For example, the sample S is a rectangular parallelepiped.

[0026] The shielding member 40 (shielding belt) shields the ion beam IB. The ion beam IB emitted from the ion source 10 is irradiated onto the sample S through the shielding member 40. The shielding member 40 is, for example, belt-shaped. The shielding member 40 is made of a material that is difficult to be milled by the ion beam IB.

[0027] The shielding member 40 is disposed on the upper surface Sa of the sample S. The thickness of the shielding member 40 (the size in the Y direction in FIG. 2) is, for example, about 10 μm. The thickness of the sample S (the size in the Y direction in FIG. 2) is, for example, about 100 μm. The shielding member 40 is disposed at the center of the sample S in the thickness direction.

[0028] The sample processing device 100 is equipped with a swing mechanism that swings the sample holder 30 and the shielding member 40. By swinging the sample holder 30, the sample S can be swung. The swing mechanism swings the sample holder 30 and the shielding member 40 around an axis parallel to the Y axis as the tilt axis. The swing mechanism swings the sample holder 30 and the shielding member 40, for example, at a constant cycle.

[0029] The illumination device 50 emits illumination light for illuminating the sample S. The illumination device 50, the sample S, the optical system 62, and the camera 60 are arranged in this order along the Y axis.

[0030] The camera 60 photographs the sample S, which is transilluminated with the illumination light emitted by the illumination device 50, via the optical system 62. The camera 60 is, for example, a digital camera such as a CCD camera or a CMOS camera. The optical system 62 is an optical system for photographing the sample S with the camera 60.

[0031] The current measuring device 70 measures the amount of current of the ion beam IB. The current measuring device 70 is disposed below (in the −Z direction) the sample S held by the sample holder 30.

[0032] The measurement unit 80 is, for example, a personal computer (PC) or the like, and includes a processor such as a CPU (Central Processing Unit) and storage devices (memories) such as RAM (Random Access Memory) and ROM (Read Only Memory). The storage devices store programs and data for performing various arithmetic processes and various control processes. The measurement unit 80 performs various arithmetic processes and various control processes by executing the programs in the processor.

[0033] The measurement unit 80 controls the ion source tilt mechanism 20 via a control circuit 82. The processing of the measurement unit 80 will be described in detail later.

[0034] The sample processing device 100 further includes a tilt angle measuring device, which will be described later.

[0035] 1.2. Operation of the sample processing device FIG. 3 is a diagram for explaining the operation of the ion source 10. As shown in FIG.

[0036] In the sample processing device 100, when an ion beam IB is emitted from the ion source 10, the ion beam IB is irradiated onto the sample S via the shielding member 40. As shown in FIG. 3, the ion source tilt mechanism 20 oscillates the ion source 10 within a predetermined tilt angle range, with axis O as the tilt axis. The axis O is located on the upper surface Sa of the sample S. The axis O is parallel to the X-axis. The ion source 10 oscillates along a circle centered on the axis O in the YZ plane.

[0037] For example, the center C of the tilt angle range of the ion source 10 is set to 0°, and the tilt angle θ0 of the ion source 10 is set to A° (A is a positive number). Although not shown, the ion source tilt mechanism 20 is equipped with a first sensor that determines the position of the center C of the tilt angle range, a second sensor that determines the upper limit position of the tilt angle range, and a third sensor that determines the lower limit position of the tilt angle range. The center C can be set by adjusting the position of the first sensor, and the tilt angle θ0 of the ion source 10 can be set by adjusting the positions of the second and third sensors.

[0038] The ion source tilt mechanism 20 first rotates the ion source 10 clockwise from the center C, which is at the position where the tilt angle θ = 0°, to set the tilt angle θ0 of the ion source 10 to +A°. This sets the tilt angle θ1 of the ion beam IB to +A°. As a result, the incident angle of the ion beam IB with respect to the processing surface Sc becomes A°. The processing surface Sc is the side surface of the sample S that is connected to the top surface Sa of the sample S.

[0039] Next, the ion source tilt mechanism 20 rotates the ion source 10 counterclockwise to set the tilt angle θ0 of the ion source 10 to -A°. This sets the tilt angle θ1 of the ion beam IB to -A°. As a result, the incident angle of the ion beam IB with respect to the processing surface Sc becomes A°. The processing surface Sb is the side surface of the sample S that is connected to the top surface Sa of the sample S, and is the surface opposite to the processing surface Sc.

[0040] The ion source tilt mechanism 20 repeats the operation of rotating the above-mentioned ion source 10 clockwise to set the tilt angle θ0 of the ion source 10 to +A°, and then rotating the ion source 10 counterclockwise to set the tilt angle θ0 of the ion source 10 to -A°.

[0041] The tilt angle θ1 of the ion beam IB is the tilt angle of the ion beam IB with respect to the sample S. The tilt angle θ1 of the ion beam IB is the tilt angle of the ion beam IB with respect to the processed surface of the sample S. In the example shown in FIG. 3, the processed surfaces Sb and Sc of the sample S are parallel to the Z axis, and when the ion beam IB is parallel to the Z axis, θ1=0°, and the clockwise angle between the Z axis and the ion beam IB is "+", and the counterclockwise angle between the Z axis and the ion beam IB is "-". is represented by "-". The tilt angle θ0 of the ion source 10 is also represented in the same manner as the tilt angle θ1 of the ion beam IB.

[0042] In the above, the center C and the tilt angle θ0 are set using three sensors, but the measurement unit 80 may receive the settings of the center C and the tilt angle θ0 and control the ion source tilt mechanism 20.

[0043] 4 is a diagram illustrating the swinging operation of the sample S. As shown in FIG. 4, the swing mechanism swings the sample S and the shielding member 40 about axis B as the tilt axis. Axis B is an axis parallel to the Y axis. Axis B is located, for example, on the upper surface Sa of the sample S.

[0044] FIG. 5 is a diagram showing a schematic view of how the sample S is processed by the sample processing device 100. As shown in FIG.

[0045] As described above, the ion source 10 and the sample S are oscillated while the sample S is irradiated with the ion beam IB through the shielding member 40, thereby milling the processed surfaces Sb and Sc as shown in Fig. 5. The processing ends when the sample S becomes thin enough that a small hole is formed in the sample S. The area around this hole becomes a thin film that can be observed with a transmission electron microscope.

[0046] 1.3. Ion beam tilt angle at the center of the tilt angle range FIG. 6 is a diagram for explaining the operation of the ion source 10 when the tilt angle θ1 of the ion beam IB is not 0° at the center C of the tilt angle range of the ion source 10. In FIG.

[0047] As shown in Figure 6, if the tilt angle θ1 of the ion beam IB is not 0° at the center C of the tilt angle range of the ion source 10, a discrepancy will occur between the incident angle of the ion beam IB with respect to the processing surface Sb of the sample S and the incident angle of the ion beam IB with respect to the processing surface Sc of the sample S.

[0048] For example, if the tilt angle θ1 of the ion beam IB is a° (a≠0) at the center C of the tilt angle range of the ion source 10, when the tilt angle θ0 of the ion source 10 is set to +A°, the tilt angle θ1 of the ion beam IB becomes A+a°. Also, when the tilt angle θ0 of the ion source 10 is set to -A°, the tilt angle θ1 of the ion beam IB becomes -A+a°. Therefore, the incident angle of the ion beam IB with respect to the processing surface Sc becomes |A+a|°, and the incident angle of the ion beam IB with respect to the processing surface Sb becomes |-A+a|°.

[0049] FIG. 7 is a diagram schematically showing a sample S that has been processed in a state where the angle of incidence of the ion beam IB on the processing surface Sb is different from the angle of incidence of the ion beam IB on the processing surface Sc.

[0050] When the incident angle of the ion beam IB to the processing surface Sb is different from the incident angle of the ion beam IB to the processing surface Sc, a difference occurs in the milling rate between the processing surface Sc and the processing surface Sb. In particular, when the incident angle of the ion beam IB to the processing surface is set to a low angle, even a slight difference in the incident angle can result in a large difference in the milling rate.

[0051] If there is a difference between the milling rate of the processed surface Sc and the milling rate of the processed surface Sb, there will be a difference between the processed depth of the processed surface Sc and the processed depth of the processed surface Sb, which may result in holes being drilled in unintended locations or the processing taking a long time.

[0052] Therefore, the ion source tilt mechanism 20 must be adjusted so that the tilt angle θ1 of the ion beam IB becomes 0° at the center C of the tilt angle range of the ion source 10.

[0053] FIG. 8 is a diagram showing a state in which the ion source tilt mechanism 20 is adjusted so that the tilt angle θ1 of the ion beam IB becomes 0° at the center C of the tilt angle range of the ion source 10.

[0054] 8, by adjusting the ion source tilt mechanism 20 so that the tilt angle θ1 is 0° at the center C of the tilt angle range of the ion source 10, it is possible to reduce the difference between the incident angle of the ion beam IB with respect to the processed surface Sb of the sample S and the incident angle of the ion beam IB with respect to the processed surface Sc of the sample S. If the tilt angle θ1 of the ion beam IB can be measured, the ion source tilt mechanism 20 can be easily adjusted.

[0055] 1.4. Tilt angle measuring device Fig. 9 is a perspective view that schematically shows the tilt angle measuring instrument 1. Fig. 10 is a cross-sectional view that schematically shows the tilt angle measuring instrument 1.

[0056] 9 and 10, the tilt angle measuring instrument 1 includes a base body 2. The base body 2 includes a slit 4 and a marker 6.

[0057] The substrate 2 is made of a conductive material. The substrate 2 is also made of a material that is not easily sputtered by the ion beam IB. The substrate 2 is made of a metal such as stainless steel (Steel Special Use Stainless, SUS). The substrate 2 is, for example, a block made of metal.

[0058] The substrate 2 has a first portion 2a that is attached to the sample stage of the sample processing device 100, and a second portion 2b that is irradiated with the ion beam IB.

[0059] The first portion 2a has a first surface 8a and a second surface 8b facing in the opposite direction to the first surface 8a. The first surface 8a is perpendicular to the direction of the depth D of the slit 4. Similarly, the second surface 8b is perpendicular to the direction of the depth D of the slit 4. The second surface 8b serves as a mounting surface when mounted on a sample stage. When the second surface 8b is mounted on the sample stage, the depth direction of the slit 4 becomes the vertical direction.

[0060] The second portion 2b extends from the first portion 2a. A slit 4 is provided in the second portion 2b. The slit 4 penetrates the second portion 2b. A first opening 4a of the slit 4 is provided in a third surface 9a of the second portion 2b, and a second opening 4b of the slit 4 is provided in a fourth surface 9b of the second portion 2b. The fourth surface 9b faces in the opposite direction to the third surface 9a. The ion beam IB is irradiated onto the third surface 9a where the first opening 4a is provided. That is, the tilt angle measurement device 1 is attached to the sample stage so that the first opening 4a faces the ion source 10.

[0061] The diameter of the ion beam IB is about 1 mm. The width W of the slit 4 is, for example, 0.1 mm. The length L of the slit 4 is, for example, 6 mm, and the depth D of the slit 4 is, for example, 6 mm.

[0062] The second portion 2b has, for example, a base portion 2b-1 connected to the first portion 2a and a tip portion 2b-2. The slit 4 is formed by screwing the tip portion 2b-2 to the base portion 2b-1, spaced apart by the width W of the slit 4. The method for forming the slit 4 is not particularly limited.

[0063] The marker 6 is a mark for indicating the irradiation position of the ion beam IB. The marker 6 is provided on the third surface 9a of the second portion 2b. The marker 6 is provided at the center of the slit 4 in the longitudinal direction.

[0064] In the above description, the second surface 8b is used as the installation surface, but the first surface 8a may also be used as the installation surface. In this case, the tilt angle θ1 of the ion beam IB can be measured in the same manner as in the case where the first surface 8a is used as the installation surface. When the first surface 8a is used as the installation surface, the ion beam IB is irradiated onto the fourth surface 9b on which the second opening 4b is provided. That is, the tilt angle measurement device 1 is attached to the sample stage so that the second opening 4b faces the ion source 10. Furthermore, the markers 6 may be provided on both the third surface 9a of the second portion 2b and the fourth surface 9b of the second portion 2b. In this way, by using the first surface 8a and the second surface 8b as installation surfaces in the tilt angle measurement device 1, the usable time of the tilt angle measurement device 1 can be doubled compared to when only the second surface 8b is used as the installation surface.

[0065] 1.5. Method for measuring the tilt angle of the ion beam Fig. 11 is a flowchart showing an example of a method for measuring the tilt angle θ1 of the ion beam IB in the sample processing device 100. Figs. 12 to 20 are diagrams for explaining the method for measuring the tilt angle θ1 of the ion beam IB.

[0066] First, the tilt angle measuring device 1 is attached to the sample stage 110 of the sample processing device 100 (S100).

[0067] 12, a silicon substrate (wafer) 102 on which a silicon oxide film is formed is mounted on an axis alignment holder 104. Next, the axis alignment holder 104 is attached to the sample stage 110 of the sample processing device 100.

[0068] 13, the tilt angle θ0 of the ion source 10 is set to 0°, and the silicon substrate 102 is irradiated with the ion beam IB. As a result, an ion beam mark is formed on the silicon substrate 102.

[0069] 14, the position of the alignment camera 90 of the sample processing device 100 is adjusted. Specifically, the position of the alignment camera 90 is adjusted so that the ion beam mark is positioned at the center of the field of view of the alignment camera 90. After adjusting the position of the alignment camera 90, the axis alignment holder 104 is removed from the sample stage 110.

[0070] 15, the tilt angle measurement device 1 is attached to the sample stage 110, and the tilt angle measurement device 1 is aligned. Specifically, the slit 4 of the tilt angle measurement device 1 is aligned with the irradiation position of the ion beam IB.

[0071] Specifically, first, the second surface 8b of the tilt angle measurement device 1 is placed on the sample stage 110. As a result, the depth direction of the slit 4 becomes the vertical direction (Z direction). Furthermore, the length direction of the slit 4 becomes the X direction. Next, the position of the tilt angle measurement device 1 is adjusted so that the slit 4 is located at the center of the field of view of the alignment camera 90. The position of the tilt angle measurement device 1 is adjusted so that the point where the marker 6 and the slit 4 intersect is located at the center of the field of view of the alignment camera 90. This allows the slit 4 to be aligned with the irradiation position of the ion beam IB.

[0072] After the tilt angle measurement device 1 is aligned, it is placed below the ion source 10. At this time, the axis O is located at the center of the slit 4 in the depth direction. In this manner, the tilt angle measurement device 1 can be attached to the sample stage 110. Note that the position of the axis O, which is the tilt axis of the ion source 10, may be shifted from the center of the slit 4 in the depth direction.

[0073] Next, as shown in FIG. 16, the ion beam IB is irradiated onto the tilt angle measuring device 1 while changing the tilt angle θ1 of the ion beam IB, and the current amount of the ion beam IB that has passed through the slit 4 is measured (S102).

[0074] The tilt angle θ1 of the ion beam IB is determined by tilting the ion source 10 using the ion source tilt mechanism 20. That is, by changing the tilt angle θ0, the tilt angle θ1 is changed.

[0075] In this step S102, the ion source 10 is tilted within a preset tilt angle range. The tilt angle range of the ion source 10 in this step S102 is not particularly limited as long as it includes an angle at which the optical axis direction of the ion beam IB is the same as the depth direction of the slit 4. The optical axis direction of the ion beam IB is the direction in which the optical axis of the ion beam IB extends, and is the same as the traveling direction of the ion beam IB. In the illustrated example, the center C of the tilt angle range is set to a tilt angle θ0 = 0°. Note that the position of the center C of the tilt angle range is not particularly limited.

[0076] Next, the peak of the current amount of the ion beam IB that has passed through the slit 4 is detected (S104).

[0077] As shown in FIGS. 17 to 19, as the tilt angle θ1 of the ion beam IB changes, the amount of current of the ion beam IB passing through the slit 4 also changes. When the optical axis direction of the ion beam IB coincides with the depth direction of the slit 4, the amount of current of the ion beam IB passing through the slit 4 is maximum. Since the depth direction of the slit 4 is the vertical direction (Z direction), when the amount of current of the ion beam IB passing through the slit 4 is maximum, the tilt angle θ1 of the ion beam IB is 0°. Therefore, by detecting the peak of the amount of current of the ion beam IB passing through the slit 4, the tilt angle θ1 of the ion beam IB can be measured.

[0078] FIG. 20 is a graph showing the relationship between the tilt angle θ1 of the ion beam IB and the current amount I of the ion beam IB.

[0079] The graph shown in Figure 20 can be created by plotting the amount of current I against the tilt angle θ1. For example, the above-described measurement may be repeated to find the average of the amount of current I at each tilt angle θ1. This can improve measurement accuracy.

[0080] Next, the peak of the current amount I is detected using a graph showing the relationship between the tilt angle θ1 and the current amount I shown in FIG.

[0081] For example, the half-width of the peak is determined from the graph shown in FIG. 20, and the center of the half-width is taken as the position of the peak. Alternatively, for example, the rising and falling positions of the peak may be detected from the graph shown in FIG. 20, and the position of the peak may be determined from these. Alternatively, the graph shown in FIG. 20 may be fitted with a predetermined function, and the position of the peak may be determined from the results of this fitting. In this way, by detecting the peak using the half-width, rising, and fitting, it is possible to reduce erroneous detection of the peak position due to noise or error, compared to when the position where the current amount I is maximum is taken as the position of the peak.

[0082] Here, since the depth direction of the slit 4 is the vertical direction (Z direction), the peak position, i.e., the tilt angle θ1 at which the current amount I reaches its peak, represents the position at which the tilt angle θ1 of the ion beam IB is 0°. In other words, the peak position represents the position of the center C of the tilt angle range of the ion source 10.

[0083] 20, the value of the tilt angle θ1 at which the amount of current peaks is −0.7°. Therefore, it can be seen that the center C of the tilt angle range of the ion source 10 is shifted by −0.7°.

[0084] 1.6. Adjustment of the ion source tilt mechanism FIG. 21 is a flowchart showing an example of a method for adjusting the ion source tilt mechanism 20. As shown in FIG. 1, the method for adjusting the ion source tilt mechanism 20 includes a step S200 of detecting a peak of the current amount I of the ion beam IB that has passed through the slit 4 by the above-described method for measuring the tilt angle of the ion beam IB, and a step S202 of adjusting the ion source tilt mechanism 20 based on the peak.

[0085] The peak of the current amount I of the ion beam IB passing through the slit 4 is detected by the method for measuring the tilt angle of the ion beam IB shown in FIG. 11 described above (S200).

[0086] Next, the ion source tilt mechanism 20 is adjusted so that the peak position is at the center C of the tilt angle range of the ion source 10 (S202).

[0087] For example, the ion source tilt mechanism 20 is adjusted by aligning the position of the first sensor that determines the position of the center C in the ion source tilt mechanism 20 with the peak position. In the example shown in Fig. 20, the center C of the tilt angle range is shifted by -0.7°. This allows the tilt angle θ1 of the ion beam IB to be 0° at the center C of the tilt angle range of the ion source 10, as shown in Fig. 8.

[0088] Through the above steps, the ion source tilt mechanism 20 can be adjusted.

[0089] 1.7. Processing of the measuring section In the sample processing apparatus 100, the measurement unit 80 detects the peak of the amount of current I that passes through the slit 4 when the tilt angle measurement device 1 is irradiated with the ion beam IB while changing the tilt angle θ1 of the ion beam IB, and controls the ion source tilt mechanism 20 based on the detected peak. Fig. 22 is a flowchart showing an example of processing by the measurement unit 80.

[0090] The measurement unit 80 acquires information on the current I of the ion beam IB that has passed through the slit 4, measured by the current measuring device 70, while changing the tilt angle θ0 of the ion source 10 using the ion source tilt mechanism 20 (S300).

[0091] Next, the measurement unit 80 detects the peak of the current amount I of the ion beam IB that has passed through the slit 4 (S302). In the process of detecting the peak, as described above, the current amount I is plotted against the tilt angle θ1 on a graph to detect the peak. This makes it possible to measure the tilt angle θ1 of the ion beam IB.

[0092] Next, the measurement unit 80 controls the ion source tilt mechanism 20 based on the peak of the current amount I (S304).

[0093] When the tilt angle of the ion source 10 is set, the measurement unit 80 offsets the tilt angle so that the peak position is at the center C of the tilt angle range. For example, in the example shown in Fig. 6, when the tilt angle range of the ion source 10 is set to -A° to +A°, the measurement unit 80 controls the ion source tilt mechanism 20 with the set tilt angle range being -A+a° to +A+a°. This makes it possible to set the tilt angle θ1 of the ion beam IB to 0° at the center C of the tilt angle range of the ion source 10.

[0094] In this way, the measurement unit 80 controls the ion source tilt mechanism 20 by applying an offset to the set tilt angle. Note that the measurement unit 80 may also move the position of the first sensor that determines the center C of the tilt angle range based on the peak of the current amount I.

[0095] Effects The method for measuring the tilt angle of the ion beam IB in the sample processing device 100 is as follows: The method includes the steps of: attaching the provided tilt angle measuring device 1 to the sample stage 110 of the sample processing device 100; irradiating the ion beam IB onto the tilt angle measuring device 1 while changing the tilt angle θ1 of the ion beam IB, and measuring the amount of current I of the ion beam IB that has passed through the slit 4; and detecting the peak of the amount of current I of the ion beam IB that has passed through the slit 4. Therefore, this measurement method can measure the tilt angle θ1 of the ion beam IB. Therefore, the ion source tilt mechanism 20 can be easily adjusted.

[0096] In the method for measuring the tilt angle of the ion beam IB in the sample processing device 100, in the step of determining the tilt angle θ1 of the ion beam IB, the amount of current I of the ion beam IB passing through the slit 4 versus the tilt angle θ1 of the ion beam IB is plotted on a graph, and the peak is detected. This allows the relationship between the tilt angle θ1 and the amount of current I to be accurately grasped, and therefore the peak can be accurately detected.

[0097] In a method for measuring the tilt angle of an ion beam IB in a sample processing device 100, the tilt angle measuring device 1 is attached to the sample stage 110 so that the depth direction of the slit 4 is vertical. This makes it possible to know the position of the center C of the tilt angle range of the ion source 10.

[0098] In the method for measuring the tilt angle of the ion beam IB in the sample processing device 100, the tilt angle θ1 of the ion beam IB is changed by tilting the ion source 10 using the ion source tilt mechanism 20. Therefore, the ion source tilt mechanism 20 can be adjusted.

[0099] The method for adjusting the ion source tilt mechanism 20 in the sample processing apparatus 100 includes the steps of detecting a peak in the current amount I of the ion beam IB by the above-described method for measuring the tilt angle θ1, and adjusting the ion source tilt mechanism 20 based on the peak. With this adjustment method, the tilt angle θ1 of the ion beam IB can be measured, and therefore the ion source tilt mechanism 20 can be easily adjusted.

[0100] The sample processing device 100 includes an ion source 10 that irradiates an ion beam IB onto a sample S, a sample holder 30 that holds the sample S, a tilt angle measuring device 1 including a slit 4 through which the ion beam IB passes, an ion source tilt mechanism 20 that tilts the ion beam IB, a current measuring device 70 that measures the amount of current I of the ion beam IB that has passed through the slit 4 of the tilt angle measuring device 1, and a measuring unit 80 that detects the peak of the amount of current I of the ion beam IB that has passed through the slit 4 when the ion beam IB is irradiated onto the tilt angle measuring device 1 while changing the tilt angle θ1 of the ion beam IB.

[0101] Therefore, the tilt angle of the ion beam IB can be measured in the sample processing apparatus 100. Furthermore, the measurement unit 80 controls the ion source tilt mechanism 20 based on the peak of the current amount I of the ion beam IB that has passed through the slit 4. In this way, in the sample processing apparatus 100, the measurement unit 80 controls the ion source tilt mechanism 20 based on the measurement result of the tilt angle of the ion beam IB. Therefore, the sample processing apparatus 100 can easily prepare a good sample for a transmission electron microscope.

[0102] In the sample processing device 100, the measurement unit 80 plots the current I of the ion beam IB that has passed through the slit 4 against the tilt angle θ1 of the ion beam IB on a graph, and detects the peak of the current I of the ion beam IB. Therefore, the sample processing device 100 can accurately detect the peak.

[0103] The tilt angle measuring device 1 is a device for measuring the tilt angle θ1 of an ion beam IB in a sample processing device that processes a sample S by irradiating the ion beam IB onto the sample S, and includes a slit 4 through which the ion beam IB passes. In such a tilt angle measuring device 1, when the optical axis direction of the ion beam IB and the depth direction of the slit 4 coincide, the slit 4 is opened. Since the current amount of the passing ion beam IB becomes maximum, the tilt angle θ1 of the ion beam IB can be measured.

[0104] The tilt angle measuring instrument 1 has a second surface 8b that serves as a mounting surface to be mounted on the sample stage 110 of the sample processing device 100, and when the second surface 8b is mounted on the sample stage 110, the depth direction of the slit 4 becomes vertical. Therefore, in the tilt angle measuring instrument 1, the depth direction of the slit 4 can easily be made vertical.

[0105] Figure 23 is a cross-sectional SEM image of a sample processed by the sample processing apparatus 100 after adjusting the ion source tilt mechanism 20 by the above-mentioned adjustment method. Figure 24 is a cross-sectional SEM image of a sample processed by the sample processing apparatus 100 before adjusting the ion source tilt mechanism 20 by the above-mentioned adjustment method. Here, in the sample processing apparatus 100, the sample S was processed with the tilt angle θ1 of the ion beam IB fixed at the center C of the tilt angle range.

[0106] As shown in FIG. 24, before the ion source tilt mechanism 20 was adjusted, there was a large difference between the milling rate on the front surface of the sample and the milling rate on the back surface of the sample.

[0107] 23, after adjusting the ion source tilt mechanism 20, the difference between the milling rate on the front surface of the sample and the milling rate on the back surface of the sample could be reduced. In this way, by adjusting the ion source tilt mechanism 20, the difference between the milling rate on the front surface of the sample and the milling rate on the back surface of the sample could be reduced. In other words, by adjusting the ion source tilt mechanism 20, the tilt angle θ1 of the ion beam IB could be accurately controlled.

[0108] For example, by setting the width W of the slit 4 shown in Figures 9 and 10 to 0.1 mm, the length L of the slit 4 to 6 mm, and the depth D of the slit 4 to 6 mm, the tilt angle θ1 of the ion beam could be corrected with an accuracy of less than 0.1°.

[0109] In this way, the above-described adjustment method can correct the tilt angle θ1 of the ion beam IB with high precision. Therefore, as shown in FIG. 23, even when the tilt angle θ1 of the ion beam IB is fixed at the center C of the tilt angle range, i.e., when the tilt angle θ1 = 0°, the front and back surfaces of the sample can be milled uniformly.

[0110] 2. Second embodiment 2.1. Sample processing equipment Next, a sample processing apparatus according to a second embodiment will be described with reference to the drawings. Figure 25 is a diagram showing the configuration of a sample processing apparatus 200 according to the second embodiment. Hereinafter, in the sample processing apparatus 200 according to the second embodiment, components having the same functions as those of the sample processing apparatus 100 according to the first embodiment will be given the same reference numerals, and detailed description thereof will be omitted.

[0111] As shown in Figure 25, the sample processing apparatus 200 includes a sample holder tilting mechanism 22 that tilts the sample holder 30. The sample processing apparatus 200 does not include the ion source tilting mechanism 20 shown in Figure 1. That is, in the sample processing apparatus 200, the ion source 10 is fixed.

[0112] The sample holder tilting mechanism 22 tilts the sample holder 30. The sample holder tilting mechanism 22 tilts the sample holder 30, thereby tilting the sample S. The sample holder tilting mechanism 22 tilts the sample holder 30 by, for example, being driven by a motor.

[0113] 2.2. Operation of the sample processing device FIG. 26 is a diagram for explaining the operation of the sample holder 30. The movement of the sample S fixed to the sample holder 30 is shown to illustrate the movement of the sample holder 30.

[0114] In the above-described sample processing apparatus 100, the tilt angle θ1 of the ion beam IB is changed by tilting the ion source 10, as shown in Fig. 3. In contrast, in the sample processing apparatus 200, the tilt angle θ1 of the ion beam IB is changed by tilting the sample S. Except for this point, the operation of the sample processing apparatus 200 is the same as that of the sample processing apparatus 100, and a detailed description thereof will be omitted.

[0115] The sample holder tilt mechanism 22 oscillates the sample S within a predetermined tilt angle range around an axis O. The axis O is located on the upper surface Sa of the sample S.

[0116] 2.3. Method for measuring the tilt angle of the ion beam The method for measuring the tilt angle θ1 of the ion beam IB in the sample processing apparatus 200 is the same as the method for measuring the tilt angle θ1 of the ion beam IB in the sample processing apparatus 100 shown in Figure 11 described above, except that the tilt angle θ1 of the ion beam IB is changed by tilting the tilt angle measuring device 1. Below, differences from the example of the measurement method in the sample processing apparatus 100 described above will be described, and similarities will not be described. Figures 27 to 29 are diagrams for explaining the method for measuring the tilt angle θ1 of the ion beam IB.

[0117] First, as shown in FIG. 27, the tilt angle measuring device 1 is attached to the sample stage 110 of the sample processing device 200 (S100).

[0118] In the sample processing device 200, the tilt angle measuring device 1 is tilted, and by aligning the slit 4 of the tilt angle measuring device 1 with the irradiation position of the ion beam IB, the axis O, which is the tilt axis of the sample S, can be aligned with the irradiation position of the ion beam IB.

[0119] Next, the ion beam IB is irradiated onto the tilt angle measuring device 1 while changing the tilt angle θ1 of the ion beam IB, and the current amount I of the ion beam IB that has passed through the slit 4 is measured (S102).

[0120] In the sample processing device 200, the tilt angle θ1 of the ion beam IB is changed by tilting the tilt angle measuring device 1 using the sample holder tilt mechanism 22. Here, the tilt angle θ1 of the ion beam IB is the tilt of the ion beam IB with respect to the tilt angle measuring device 1 (slit 4).

[0121] Next, the peak of the current amount of the ion beam IB that has passed through the slit 4 is detected (S104).

[0122] 28 and 29, as the tilt angle θ1 of the ion beam IB changes, the current amount I of the ion beam IB passing through the slit 4 also changes. When the optical axis direction of the ion beam IB coincides with the depth direction of the slit 4, the current amount I of the ion beam IB passing through the slit 4 becomes maximum. Therefore, similar to the example of the sample processing apparatus 100 described above, the tilt angle θ1 of the ion beam IB can be measured by detecting the peak of the current amount I of the ion beam IB passing through the slit 4. The position of the peak represents the position of the center C of the tilt angle range of the sample S.

[0123] 2.4. How to adjust the sample holder tilt mechanism 30 is a flowchart showing an example of a method for adjusting the sample holder tilt mechanism 22 in the sample processing device 200. FIG. 31 shows a flow chart showing an example of a method for adjusting the tilt angle of the sample S at the center C of the tilt angle range of the sample S. FIG. 10 is a diagram showing a state in which the sample holder tilt mechanism 22 is adjusted so that the tilt angle θ1 of the beam IB is 0°.

[0124] The method for adjusting the sample holder tilt mechanism 22 in the sample processing apparatus 200 is similar to the method for adjusting the ion source tilt mechanism 20 in the sample processing apparatus 100 shown in Fig. 21 described above, except that the sample holder tilt mechanism 22 is adjusted based on the peak of the current amount I of the ion beam IB. Below, differences from the example of the adjustment method in the sample processing apparatus 100 described above will be explained, and explanation of similarities will be omitted.

[0125] The peak of the current amount I of the ion beam IB passing through the slit 4 is detected by the above-mentioned method for measuring the tilt angle θ1 of the ion beam IB (S400).

[0126] Next, the sample holder tilt mechanism 22 is adjusted so that the peak position is at the center C of the tilt angle range of the sample S (S402).

[0127] Similar to the method for adjusting the ion source tilt mechanism 20, the sample holder tilt mechanism 22 is adjusted by aligning the position of a sensor that determines the center C of the tilt angle range in the sample holder tilt mechanism 22 with the peak position. This allows the tilt angle θ1 of the ion beam IB to be set to 0° at the center C of the tilt angle range of the sample S, as shown in Figure 31.

[0128] Through the above steps, the sample holder tilt mechanism 22 can be adjusted.

[0129] 2.5. Processing of the measurement section In the sample processing apparatus 200, the measurement unit 80 detects the peak of the current I that passes through the slit 4 when the tilt angle measurement device 1 is irradiated with the ion beam IB while changing the tilt angle θ1 of the ion beam IB, and controls the sample holder tilt mechanism 22 based on the detected peak. Fig. 32 is a flowchart showing an example of processing by the measurement unit 80.

[0130] The measurement unit 80 acquires information on the amount of current I of the ion beam IB that has passed through the slit 4 measured by the current measurement unit 70 while changing the tilt angle of the tilt angle measurement unit 1 using the sample holder tilt mechanism 22 (S500). Next, the measurement unit 80 detects the peak of the amount of current I of the ion beam IB that has passed through the slit 4 (S502). This makes it possible to measure the tilt angle θ1 of the ion beam IB.

[0131] Next, the measurement unit 80 controls the sample holder tilt mechanism 22 based on the tilt angle of the tilt angle measuring device 1 at which the amount of current I reaches its peak (S504).

[0132] When the tilt angle of the sample S is set, the measurement unit 80 offsets the tilt angle so that the peak position is at the center C of the tilt angle range. This allows the tilt angle θ1 of the ion beam IB to be 0° at the center C of the tilt angle range of the sample S.

[0133] Effects In the method for measuring the tilt angle of the ion beam IB in the sample processing apparatus 200, the tilt angle θ1 of the ion beam IB is changed by tilting the tilt angle measuring device 1 using the sample holder tilt mechanism 22. This makes it possible to change the incident angle of the ion beam IB with respect to the tilt angle measuring device 1, just as when the tilt angle θ1 of the ion beam IB is changed by tilting the ion source 10. Therefore, it is possible to achieve the same effects as the measurement method in the sample processing apparatus 100 described above.

[0134] In the method for adjusting the sample holder tilt mechanism 22 in the sample processing device 200, the slit 4 is The sample holder tilt mechanism 22 is adjusted based on the peak of the passed current amount I. Therefore, the same effects as those of the adjustment method in the sample processing apparatus 100 described above can be achieved.

[0135] In the sample processing apparatus 200, the measurement unit 80 detects the peak of the current amount I and controls the sample holder tilt mechanism 22 based on the peak of the current amount I. The sample processing apparatus 200 can achieve the same effects as the sample processing apparatus 100.

[0136] 3. Variations 3.1. First Variant In the first embodiment described above, when the tilt angle measuring instrument 1 is set on the sample stage 110, the axis O is positioned on the upper surface Sa of the sample S, and the ion beam IB is irradiated at the position of this axis O to form an ion beam mark on the silicon substrate 102, but the position of the axis O is not particularly limited.

[0137] For example, if the position of the axis O is shifted in the vertical direction (+Z direction or -Z direction) from the position where the ion beam mark is formed, for example, by tilting the ion source 10 by +A° to form the ion beam mark, and then tilting the ion source 10 by -A° to form the ion beam mark, an elliptical or dumbbell-shaped ion beam mark can be formed on the silicon substrate 102. The center of the longitudinal direction of this ion beam mark can be set as the irradiation position of the ion beam IB. This allows the tilt angle to be measured with higher accuracy. The same applies to the second embodiment.

[0138] 3.2. Second Variant 33 and 34 are cross-sectional views schematically showing modified examples of the tilt angle measurement instrument 1. As shown in Fig. 10, the depth direction of the slit 4 is perpendicular to the second surface 8b, which is the installation surface of the tilt angle measurement instrument 1.

[0139] 33 and 34, the depth direction of the slit 4 does not have to be perpendicular to the second surface 8b. In such a tilt angle measuring instrument 1, by calibrating the measured tilt angle using a calibration value, the tilt angle can be measured in the same way as when the depth direction of the slit 4 is perpendicular to the second surface 8b as shown in FIG.

[0140] Fig. 35 is a graph showing the results of measuring the tilt angle of the ion beam IB using the tilt angle measurement instrument 1 according to the modified example. Fig. 35 shows the measurement results of the amount of current I when the second surface 8b is used as the installation surface and the measurement results of the amount of current I when the first surface 8a is used as the installation surface. Note that the measurement results of the amount of current I when using the tilt angle measurement instrument 1 in which the depth direction of the slit 4 is perpendicular to the second surface 8b shown in Fig. 10 are shown by a dashed line.

[0141] The true tilt angle is the midpoint between the value obtained by the method for measuring the tilt angle of the ion beam IB described above using the second surface 8b shown in Fig. 33 as the installation surface and the value obtained by the method for measuring the tilt angle of the ion beam IB described above using the first surface 8a shown in Fig. 34 as the installation surface. Therefore, based on the measurement results when the second surface 8b is used as the installation surface and the measurement results when the first surface 8a is used as the installation surface, it is possible to obtain the calibration values ​​when measuring when the first surface 8a is used as the installation surface and the calibration values ​​when measuring when the second surface 8b is used as the installation surface.

[0142] In this way, it is possible to obtain the calibration value when the second surface 8b is the installation surface and the calibration value when the first surface 8a is the installation surface, so even if the depth direction of the slit 4 is not perpendicular to the second surface 8b, the second surface 8b or the first surface 8a may be the installation surface.

[0143] 3.3. Third Variant In the first embodiment described above, the current amount I of the ion beam IB that has passed through the slit 4 is directly measured by the current measuring device 70. However, the method for measuring the current amount I of the ion beam IB that has passed through the slit 4 is not limited to this. For example, the current amount I of the ion beam IB that has passed through the slit 4 may be measured by measuring the current amount of the ion beam IB irradiated onto the tilt angle measuring device 1. The current amount of the ion beam IB emitted from the ion source 10 is the sum of the current amount of the ion beam IB that has passed through the slit 4 and the current amount of the ion beam IB that has irradiated onto the tilt angle measuring device 1. Therefore, the current amount of the ion beam IB that has passed through the slit 4 can be measured by measuring the current amount of the ion beam IB that has irradiated onto the tilt angle measuring device 1.

[0144] The above-described embodiment and modifications are merely examples, and the present invention is not limited to these. For example, the embodiments and modifications can be combined as appropriate.

[0145] The present invention is not limited to the above-described embodiments, and various modifications are possible. For example, the present invention includes configurations that are substantially identical to the configurations described in the embodiments. A substantially identical configuration means, for example, a configuration with the same function, method, and result, or a configuration with the same purpose and effect. The present invention also includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. The present invention also includes configurations that achieve the same effects or purposes as the configurations described in the embodiments. The present invention also includes configurations in which publicly known technology is added to the configurations described in the embodiments. [Explanation of symbols]

[0146] REFERENCE SIGNS LIST 1...tilt angle measuring device, 2...base body, 2a...first portion, 2b...second portion, 2b-1...base portion, 2b-2...tip portion, 4...slit, 4a...first opening, 4b...second opening, 6...marker, 8a...first surface, 8b...second surface, 9a...third surface, 9b...fourth surface, 10...ion source, 20...ion source tilt mechanism, 22...sample holder tilt mechanism, 30...sample holder, 40...shielding member, 50...illumination device, 60...camera, 62...optical system, 70...current measuring device, 80...measurement unit, 82...control circuit, 90...alignment camera, 100...sample processing device, 102...silicon substrate, 104...holder, 110...sample stage, 200...sample processing device

Claims

1. A method for measuring a tilt angle of an ion beam in a sample processing apparatus that processes a sample by irradiating the sample with an ion beam, comprising: a step of attaching a tilt angle measuring device provided with a slit to a sample stage of the sample processing device; irradiating the tilt angle measuring device with the ion beam while changing the tilt angle of the ion beam, and measuring the current amount of the ion beam that has passed through the slit; detecting a peak of the current amount of the ion beam that has passed through the slit; , including, a measurement method.

2. In claim 1, In the step of detecting the peak, the amount of current of the ion beam that has passed through the slit is plotted against the tilt angle of the ion beam on a graph, and the peak is detected.

3. In claim 1, The tilt angle measuring device is attached to the sample stage so that the depth direction of the slit is vertical.

4. In any one of claims 1 to 3, The sample processing device includes: an ion source that emits an ion beam; an ion source tilting mechanism that tilts the ion source; Including, The measurement method includes changing the tilt angle of the ion beam by tilting the ion source using the ion source tilt mechanism.

5. In any one of claims 1 to 3, The sample processing device includes: a sample holder; a sample holder tilting mechanism for tilting the sample holder; Including, a tilt angle measuring device using the sample holder tilt mechanism, thereby changing the tilt angle of the ion beam.

6. detecting the peak by the measurement method of claim 1; adjusting a tilt mechanism that tilts the ion beam based on the peak; , including, a method of adjustment.

7. In claim 6, The tilt mechanism tilts the ion beam by tilting an ion source that emits the ion beam.

8. In claim 6, The tilt mechanism tilts the tilt angle measuring device to tilt the ion beam.

9. A sample processing device that processes a sample by irradiating the sample with an ion beam, an ion source that irradiates the sample with an ion beam; a sample holder for holding the sample; a tilt angle measuring device including a slit for passing the ion beam; a tilt mechanism for tilting the ion beam with respect to the sample; a current measuring device for measuring the current amount of the ion beam that has passed through the slit; a measuring unit that detects a peak of the current amount of the ion beam that has passed through the slit when the ion beam is irradiated onto the tilt angle measuring device while changing the tilt angle of the ion beam; A sample processing device comprising:

10. In claim 9, The measurement unit controls the tilt mechanism based on the peak.

11. In claim 9, The tilt mechanism tilts the ion source, thereby tilting the ion beam.

12. In claim 9, The tilting mechanism tilts the sample holder to tilt the ion beam.

13. In any one of claims 9 to 12, The measurement unit plots the amount of current of the ion beam that has passed through the slit against the tilt angle of the ion beam on a graph, and detects the peak.

14. 1. A tilt angle measuring device for measuring a tilt angle of an ion beam in a sample processing device that processes a sample by irradiating the sample with an ion beam, comprising: A tilt angle measuring device that includes a slit through which the ion beam passes.

15. In claim 14, a mounting surface to be mounted on a sample stage of the sample processing device; A tilt angle measuring instrument in which, when the installation surface is installed on the sample stage, the depth direction of the slit becomes the vertical direction.

16. In claim 14, The first page and a second surface facing in a direction opposite to the first surface; and when the first surface is placed on a sample stage of the sample processing device, one opening of the slit faces a direction of an ion source of the sample processing device; a tilt angle measuring device, wherein when the second surface is placed on the sample stage, the other opening of the slit faces the direction of the ion source.

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