Sample processing system, image generation apparatus, and image generation method

Abstract

To provide a sample processing system that can easily determine an appropriate processing condition.SOLUTION: A sample processing system includes a sample processing device that radiates an ion beam onto a sample to process the sample, and an image generating device that generates a predicted image of the sample when processed under a set processing condition using the sample processing device, and the predicted image includes information on the distribution of the irradiation direction of the ion beam.SELECTED DRAWING: Figure 16

Description

[Technical field]

[0001] The present invention relates to a sample processing system, an image generating device, and an image generating method. [Background technology]

[0002] Cross-Section Polisher (registered trademark) is known as a sample processing device that processes a sample using an ion beam. A known processing method using such a sample processing device is the plane milling method, which uses the sputtering phenomenon that occurs when an ion beam is irradiated at a very shallow angle to the sample surface to create a smooth plane.

[0003] For example, Patent Document 1 discloses an ion milling device that includes an ion gun that irradiates a rotating sample with an ion beam, and a sample rotation device that positions and rotates the sample so that its center of rotation is within the ion beam irradiation surface, and is characterized in that the center of rotation of the sample is shifted a predetermined distance from the center of the ion beam on the sample surface. By shifting the center of the ion beam and the center of rotation of the sample in this way, it is possible to irradiate a wide area of ​​the sample with the ion beam from various irradiation directions, compared to when the center of the ion beam and the center of rotation of the sample are aligned. This allows a wide area of ​​the sample to be smoothly etched. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 3-36285 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the direction of the ion beam during processing changes in a complex manner depending on processing conditions such as the rotation speed of the sample and the distance between the center of the ion beam and the center of rotation of the sample, making it difficult to determine appropriate processing conditions. [Means for solving the problem]

[0006] One aspect of the sample processing system according to the present invention is to a sample processing device that processes a sample by irradiating the sample with an ion beam; an image generating device that generates a predicted image of the sample when the sample is processed under set processing conditions using the sample processing device; Including, The predicted image includes information on the distribution of the irradiation direction of the ion beam.

[0007] In such a sample processing device, a predicted image of the sample when it is processed under set processing conditions can be obtained, so that appropriate processing conditions can be easily determined.

[0008] One aspect of the image generating device according to the present invention is an image generating unit that generates a predicted image of a sample when the sample is processed under set processing conditions using a sample processing device that processes the sample by irradiating the sample with an ion beam; a display control unit that displays the predicted image; Including, The predicted image includes information on the distribution of the irradiation direction of the ion beam.

[0009] Such an image generating device can generate a predicted image of the sample when it is processed under set processing conditions, so that appropriate processing conditions can be easily determined.

[0010] One aspect of the image generating method according to the present invention includes: A step of generating a predicted image of a sample when the sample is processed under set processing conditions using a sample processing device that processes the sample by irradiating the sample with an ion beam; displaying the predicted image; Including, The predicted image includes information on the distribution of the irradiation direction of the ion beam.

[0011] Such an image generation method can generate a predicted image when a sample is processed under set processing conditions, so that appropriate processing conditions can be easily determined. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram showing the configuration of a sample processing system according to a first embodiment. [Diagram 2] FIG. 1 is a diagram showing the configuration of a sample processing system according to a first embodiment. [Diagram 3] FIG. 2 is a diagram showing a schematic view of a sample supported by a sample stage. [Figure 4] FIG. 1 is a diagram showing the configuration of an image generating apparatus. [Diagram 5] 1 is a flowchart showing an example of an image generation method for generating a predicted image. [Figure 6] FIG. 2 is a diagram illustrating an example of a GUI of the image generating apparatus. [Figure 7] Ion beam image before and after correction. [Figure 8] FIG. 4 is a diagram for explaining a process of generating a predicted image at a first time point. [Figure 9] FIG. 4 is a diagram for explaining a process of generating a predicted image at a first time point. [Figure 10] FIG. 11 is a diagram for explaining a method of calculating the irradiation position of the ion beam at a second time. [Figure 11] FIG. 11 is a diagram for explaining a method of calculating the irradiation position of the ion beam at a second time. [Figure 12] FIG. 1 is a diagram for explaining component decomposition of a vector. [Figure 13] FIG. 13 is a diagram showing irradiation intensity distribution images superimposed at intervals of one second. [Figure 14] FIG. 13 is a diagram showing an image of the irradiation intensity distribution of an ion beam. [Figure 15] Graph showing the luminance profile of each irradiation intensity distribution image. [Figure 16] FIG. 13 is a diagram showing a vector component distribution image. [Figure 17] 6 is a graph showing the luminance profile of each vector component distribution image. [Figure 18] FIG. 13 is a diagram illustrating an example of a method for displaying a predicted image. [Figure 19] FIG. 13 is a diagram illustrating an example of a method for displaying a predicted image. [Figure 20] FIG. 13 is a diagram illustrating an example of a method for displaying a predicted image. [Figure 21] FIG. 13 is a diagram illustrating an example of a method for displaying a predicted image. [Figure 22] FIG. 13 is a diagram illustrating an example of a method for displaying a predicted image. [Diagram 23] 4 is a flowchart showing an example of an image generation process of the image generation device. [Figure 24] FIG. 13 is a diagram showing the configuration of an ion source of a sample processing system according to a second embodiment. [Diagram 25] FIG. 13 is a diagram showing an example of a predicted image. [Figure 26] FIG. 1 is a schematic diagram showing a state in which a sample having a laminated structure is subjected to plane milling. [Figure 27] FIG. 13 is a diagram showing an example of a predicted image. [Figure 28] FIG. 13 is a diagram showing the configuration of a sample processing system according to a third embodiment. [Figure 29] FIG. 13 is a diagram showing the configuration of a sample processing system according to a third embodiment. [Diagram 30] 1 is a diagram for explaining the relationship between the distance between the rotation center and swing center of a sample and the irradiation range of an ion beam. [Diagram 31] FIG. 13 is a diagram showing the configuration of a sample processing system according to a fourth embodiment. [Diagram 32] FIG. 13 is a diagram showing the configuration of a sample processing system according to a fourth embodiment. [Diagram 33] FIG. 13 is a diagram showing the configuration of a sample processing system according to a fifth embodiment. [Diagram 34] FIG. 13 is a diagram showing the configuration of a sample processing system according to a fifth embodiment. [Diagram 35] FIG. 13 is a diagram showing an example of an irradiation direction distribution image. [Diagram 36] FIG. 13 is a diagram showing an example of an irradiation direction distribution image. [Figure 37] FIG. 13 is a diagram showing an example of an irradiation direction distribution image. [Figure 38] FIG. 4 is a diagram showing a schematic diagram of a predicted image at a first time point. [Figure 39] FIG. 13 is a diagram showing a schematic representation of a predicted image at a second time. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] 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 contents of the present invention described in the claims. In addition, not all of the configurations described below are necessarily essential components of the present invention.

[0014] 1. First embodiment 1.1. Sample processing system First, a sample processing system according to a first embodiment will be described with reference to the drawings. Figures 1 and 2 are diagrams showing the configuration of a sample processing system 2 according to the first embodiment.

[0015] 1 and 2 show an X-axis, a Y-axis, and a Z-axis as three mutually orthogonal axes. The X-direction includes a +X direction that is one direction along the X-axis, and a -X direction that is the other direction along the X-axis. The Y-direction includes a +Y direction that is one direction along the Y-axis, and a -Y direction that is the other direction along the Y-axis. The Z-direction includes a +Z direction that is one direction along the Z-axis, and a -Z direction that is the other direction along the Z-axis.

[0016] 1 and 2, the sample processing system 2 includes a sample processing device 100 and an image generating device 200. For convenience, the image generating device 200 is not shown in FIG.

[0017] (1) Sample processing equipment The sample processing apparatus 100 processes the sample S by irradiating the sample S with an ion beam IB. The sample processing apparatus 100 is used to prepare samples for electron microscopes such as a scanning electron microscope (SEM), a transmission electron microscope (TEM), and a scanning transmission electron microscope (STEM). The sample processing apparatus 100 is also used to prepare samples for analytical instruments other than electron microscopes, such as an electron probe microanalyzer (EPMA) and an Auger microprobe.

[0018] The sample processing apparatus 100 is capable of processing by a plane milling method that creates a smooth plane by utilizing the sputtering phenomenon that occurs when an ion beam IB is irradiated at a very shallow angle to the surface of the sample S. The following describes the case where the sample S is processed by the plane milling method using the sample processing apparatus 100.

[0019] 1 and 2, the sample processing device 100 includes an ion source 110, a sample stage 120, an alignment camera 130, a processing and observation camera 140, a chamber 150, a chamber door 160, and a control unit 170. Note that Fig. 1 illustrates a state in which the chamber door 160 is closed and the sample stage 120 is pushed into the chamber 150, and Fig. 2 illustrates a state in which the chamber door 160 is open and the sample stage 120 is pulled out from the chamber 150.

[0020] The ion source 110 generates an ion beam and irradiates the generated ion beam IB onto a sample S. The ion source 110 is attached to an upper portion of a chamber 150.

[0021] The sample stage 120 supports the sample S. The sample stage 120 includes a tilt mechanism 20, a rotation mechanism 22, a swing mechanism 24, a Z stage 26, and an XY stage 28. 1 and 2, an XY stage 28 is disposed on a swing table 24a of a swing mechanism 24. A Z stage 26 is disposed on the XY stage 28. A tilt mechanism 20 is attached to the Z stage 26, and a rotation mechanism 22 is supported by the tilt mechanism 20 so as to be tiltable. A sample S is attached to the rotation mechanism 22.

[0022] Fig. 3 is a diagram showing a schematic view of the sample S supported by the sample stage 120. Fig. 3 shows a plan view of the surface Sa of the sample S and a cross-sectional view including the center of the sample S.

[0023] The tilt mechanism 20 tilts the sample S. By tilting the sample S with the tilt mechanism 20, it is possible to adjust the irradiation angle α (incident angle) of the ion beam IB with respect to the surface Sa of the sample S. The tilt mechanism 20 tilts the sample S by tilting the rotation mechanism 22. The tilt mechanism 20 includes an axis member that supports the rotation mechanism 22 so that it can be tilted, and a support part that supports the axis member. The tilt mechanism 20 may tilt the sample S by a driving device such as a motor.

[0024] The rotation mechanism 22 rotates the sample S about axis A. Axis A is perpendicular to the surface Sa of the sample S. The axis A is also tilted by tilting the rotation mechanism 22 with the tilt mechanism 20. Therefore, even if the sample S is tilted with the tilt mechanism 20, the axis A is always perpendicular to the surface Sa of the sample S. The center of rotation RC of the sample S when rotating the sample S with the rotation mechanism 22 is the position of the intersection of the surface Sa of the sample S and the axis A. The rotation mechanism 22 includes a sample stage to which the sample S is fixed, and a driving device such as a motor that rotates the sample stage.

[0025] The swing mechanism 24 swings the sample S. That is, the swing mechanism 24 moves the sample S back and forth on the circumference (reciprocating circular motion). The swing mechanism 24 swings the tilt mechanism 20, the rotation mechanism 22, the Z stage 26, and the XY stage 28 as a unit. The axis B, which is the swing axis, is parallel to the Y axis. The swing center SC of the sample S is the position of the intersection of the surface Sa of the sample S and the axis B. The swing center SC can be set at any position on the surface Sa of the sample S. The position of the swing center SC can be moved by moving the sample S by the Z stage 26 or the XY stage 28. The swing mechanism 24 includes a swing table 24a and a driving device 24b, such as a motor, that swings the swing table 24a.

[0026] The Z stage 26 moves the sample S in the Z direction. The Z stage 26 can adjust the position of the sample S in the Z direction, i.e., the height of the sample S. The Z stage 26 moves the tilt mechanism 20 in the Z direction to move the sample S in the Z direction. The Z stage 26 moves the tilt mechanism 20 and the rotation mechanism 22 in the Z direction as a unit. The Z stage 26 moves the sample S in the Z direction by using the Z stage 26 to adjust the distance D between the rotation center RC and the swing center SC. That is, in the sample processing device 100, the distance D is variable. The Z stage 26 moves the sample S in the Z direction by a driving device such as a motor. The Z stage 26 may be manually operated to move the sample S in the Z direction.

[0027] The XY stage 28 moves the sample S in the X and Y directions. The XY stage 28 can adjust the position of the sample S in the X and Y directions. The XY stage 28 moves the Z stage 26 in the X and Y directions, thereby moving the sample S in the X and Y directions. The XY stage 28 moves the tilt mechanism 20, the rotation mechanism 22, and the Z stage 26 as a unit. The XY stage 28 can adjust the distance B between the center BC of the ion beam IB and the rotation center RC. That is, in the sample processing device 100, the distance B is variable. The XY stage 28 moves the sample S in the X and Y directions by a driving device such as a motor. The XY stage 28 may be manually operated to move the sample S in the X and Y directions.

[0028] The alignment camera 130 is a camera for determining the position of the optical axis of the ion beam IB. For example, in a state where the chamber door 160 is open and the sample stage 120 is pulled out from the chamber 150, the center of the field of view of the alignment camera 130 becomes the position of the optical axis of the ion beam IB when the chamber door 160 is closed and the sample stage 120 is pushed into the chamber 150. The alignment camera 130 is disposed at a retracted position away from the ion source 110 when the chamber door 160 is closed.

[0029] The processing and observation camera 140 is a camera for observing the sample S during processing. The optical axis of the processing and observation camera 140 is parallel to the Y axis. The processing and observation camera 140 is disposed outside the chamber 150. The processing and observation camera 140 can observe the sample S in the chamber 150 through an observation window 162 provided in the chamber 150.

[0030] The sample stage 120 is housed in the chamber 150. In the sample processing apparatus 100, the sample S is irradiated with an ion beam IB in the chamber 150. The inside of the chamber 150 can be maintained in a reduced pressure state by a vacuum pump (not shown).

[0031] The chamber door 160 airtightly seals the chamber 150. The sample stage 120 is attached to the chamber door 160. The chamber door 160 is slidable relative to the chamber 150, and the chamber door 160 can be opened and closed by sliding the chamber door 160. Therefore, the sample stage 120 can be pushed into the chamber 150 by closing the chamber door 160, and the sample stage 120 can be pulled out from the chamber 150 by opening the chamber door 160.

[0032] The control unit 170 controls each unit of the sample processing device 100. The control unit 170 controls the ion source 110, for example, via the ion source control circuit 112. The ion source control circuit 112 converts a control signal from the control unit 170 into a drive signal for driving the ion source 110, and outputs the drive signal to the ion source 110. The control unit 170 also controls, for example, the sample stage 120. When processing conditions are set by the user, the control unit 170 operates the ion source 110 and the sample stage 120 in accordance with the processing conditions.

[0033] When processing the sample S by the planar milling method using the sample processing apparatus 100, the processing conditions set include the energy of the ion beam IB (acceleration voltage of the ion beam), the irradiation angle α of the ion beam IB, the rotation speed of the sample S, the swing angle range of the sample S, the swing speed of the sample S, the distance B between the rotation center RC of the sample S and the center BC of the ion beam IB, the distance D between the rotation center RC of the sample S and the swing center SC, and the processing time.

[0034] In the sample processing device 100, when the processing conditions are set, the control unit 170 controls the ion source 110 and the sample stage 120 according to the processing conditions. Specifically, the control unit 170 controls the acceleration voltage of the ion source 110 according to the energy of the set ion beam IB. The control unit 170 also controls the tilt mechanism 20 according to the set irradiation angle α of the ion beam IB. The control unit 170 also controls the rotation mechanism 22 according to the set rotation speed. The control unit 170 also controls the swing mechanism 24 according to the set swing angle range and swing speed. The control unit 170 also controls the XY stage 28 according to the set distance B between the rotation center RC of the sample S and the center BC of the ion beam IB. The control unit 170 also controls the Z stage 26 according to the set distance D between the rotation center RC of the sample S and the swing center SC.

[0035] As a result, in the sample processing device 100, the distance B between the rotation center RC of the sample S and the center BC of the ion beam IB becomes the set distance, and the distance D between the rotation center RC of the sample S and the swing center SC becomes the set distance. In addition, the tilt angle of the sample S becomes the set distance. The irradiation angle α is the angle at which the ion beam IB is incident on the surface Sa of the sample S. Then, the ion beam IB is irradiated from the ion source 110 to the sample S with a set energy (acceleration voltage). The ion beam IB is incident on the surface Sa of the sample S at the set irradiation angle α. At this time, the sample S rotates at a set rotation speed around the rotation center RC, and swings at a set swing speed within a set swing angle range around the swing center SC. The control unit 170 causes the ion source 110 to irradiate the ion beam IB for a set processing time. This allows the sample S to be processed under the set processing conditions.

[0036] In addition, the user may adjust the tilt angle of the sample S, the distance B between the rotation center RC of the sample S and the center BC of the ion beam IB, and the distance D between the rotation center RC of the sample S and the swing center SC by manually operating the sample stage 120.

[0037] (2) Image generation device Fig. 4 is a diagram showing the configuration of the image generating device 200. The image generating device 200 includes a processing unit 210, an input unit 220, a display unit 230, and a storage unit 240, as shown in Fig. 4.

[0038] The input unit 220 allows the user to input operation information and outputs the input operation information to the processing unit 210. The function of the input unit 220 can be realized by input devices such as a keyboard, a mouse, a button, and a touch panel.

[0039] The display unit 230 displays the image generated by the processing unit 210. The function of the display unit 230 can be realized by a liquid crystal display (LCD), a touch panel that also functions as the input unit 220, or the like.

[0040] The storage unit 240 stores programs and various data for causing the computer to function as each unit of the processing unit 210. The storage unit 240 also functions as a work area for the processing unit 210. The functions of the storage unit 240 can be realized by a hard disk, a RAM (Random Access Memory), or the like.

[0041] The functions of the processing unit 210 can be realized by executing a program using hardware such as various processors (CPU, DSP, etc.). The processing unit 210 includes an image generating unit 212 and a display control unit 214.

[0042] The image generating unit 212 generates a predicted image when the sample S is processed under the set processing conditions using the sample processing device 100. The predicted image includes information on the irradiation intensity of the ion beam IB and information on the irradiation direction of the ion beam IB when the sample S is processed under the set processing conditions. In other words, it is possible to know from the predicted image which position of the sample S is irradiated with the ion beam IB, the irradiation intensity of the ion beam IB, and from which irradiation direction. The image generating unit 212 performs a simulation based on the set processing conditions to generate the predicted image.

[0043] The display control unit 214 causes the display unit 230 to display the predicted image generated by the image generation unit 212.

[0044] 1.2. Image Generation Method Next, a method for generating a predicted image will be described with reference to Fig. 5, which is a flowchart showing an example of an image generating method for generating a predicted image.

[0045] 1.2.1. Processing condition acquisition process S10 First, the image generating unit 212 acquires information on processing conditions. The processing condition information input by the user via the input unit 220 is received, and the processing condition information is acquired.

[0046] FIG. 6 is a diagram showing an example of a GUI (Graphical User Interface) screen 4 of the image generating device 200. As shown in FIG.

[0047] As shown in FIG. 6, the GUI screen 4 includes a processing condition setting section G2 for setting processing conditions, a sample image display section G4 for visualizing the processing conditions and displaying the positional relationship between the sample S and the ion beam IB, and a predicted image display section G6 for displaying the generated predicted image.

[0048] The processing condition setting section G2 is provided with sliders for setting various parameters of the processing conditions. Specifically, the processing condition setting section G2 is provided with a slider for setting the energy of the ion beam IB, a slider for setting the irradiation angle α of the ion beam IB, a slider for setting the swing angle range of the sample S, a slider for setting the distance B between the rotation center RC of the sample S and the center BC of the ion beam IB, a slider for setting the distance D between the rotation center RC of the sample S and the swing center SC, and a slider for setting the processing time. Although not shown, a slider for setting the swing speed of the sample S may be provided in the processing condition setting section G2.

[0049] The GUI elements for setting parameters are not limited to sliders, and may include, for example, input fields for directly inputting parameters as numerical values ​​in the processing condition setting section G2.

[0050] The display of the processing condition setting section G2 is, for example, the same as the GUI for setting processing conditions in the sample processing device 100. Therefore, after confirming the predicted image generated by the image generating device 200 and determining the processing conditions, it is easy to input various parameters into the GUI of the sample processing device 100.

[0051] The sample image display section G4 displays an image of the sample S according to the set processing conditions. Specifically, the image of the sample S reflecting the tilt angle of the sample S (the irradiation angle of the ion beam IB), the distance B between the rotation center RC of the sample S and the center BC of the ion beam IB, and the distance D between the rotation center RC of the sample S and the swing center SC is displayed.

[0052] Here, in the sample processing device 100, the distance B is adjusted while watching the alignment camera 130. Therefore, the distance between the center of rotation RC of the sample S and the center BC of the ion beam IB as seen by the alignment camera 130, which is calculated from the tilt angle of the sample S and the distance B, is displayed in the sample image display section G4.

[0053] The generated predicted image is displayed in the predicted image display section G6. In the predicted image display section G6, the image of the sample before processing and the predicted image are displayed superimposed. In the predicted image display section G6, a slider 6 is arranged for setting the transparency when the predicted image is superimposed on the image of the sample before processing. Also, a check box 8 is arranged for displaying only half of the predicted image superimposed on the image of the sample before processing. Details of the method of displaying the predicted image in the predicted image display section G6 will be described later.

[0054] 1.2.2. Ion beam information acquisition process S20 Next, the image generating unit 212 acquires information on the ion beam IB. The information on the ion beam IB may be, for example, information on the ion beam IB obtained by irradiating the ion beam IB with a set energy at a set irradiation angle α. This is information on the distribution of brightness of the ion beam IB when it is irradiated onto the sample S. The information on the distribution of brightness of the ion beam IB can be acquired, for example, from an ion beam image obtained by photographing a test sample that emits light when irradiated with the ion beam. A method for acquiring an ion beam image will be described below.

[0055] First, a glass sample is prepared as a sample that emits light when irradiated with an ion beam. Next, as shown in FIG. 2, the chamber door 160 is opened, the sample stage 120 is pulled out from the chamber 150, and the glass sample is attached to the sample stage 120. Next, the tilt angle of the glass sample is adjusted using the tilt mechanism 20, and the irradiation angle α of the ion beam IB is set to the irradiation angle set as a processing condition. Next, the XY stage 28 is operated while observing the glass sample with the alignment camera 130, and the glass sample is aligned so that it is positioned at the irradiation position of the ion beam IB.

[0056] 1, the chamber door 160 is closed and the sample stage 120 is pushed into the chamber 150. Next, the chamber 150 is evacuated to a vacuum. Next, the energy (acceleration voltage) of the ion beam IB is set, and the glass sample is irradiated with the ion beam IB. At this time, the rotation mechanism 22 and the swing mechanism 24 are not operated, and the glass sample is kept stationary.

[0057] Next, the glass sample irradiated with the ion beam IB is photographed by the processing and observation camera 140. This makes it possible to obtain an ion beam image. At this time, the current of the ion beam IB is measured.

[0058] The captured ion beam image is an image captured from an oblique direction by the inclination angle of the glass sample with respect to the surface of the glass sample. Therefore, the captured ion beam image is stretched at a magnification rate according to the inclination angle so that the image is captured from a direction perpendicular to the surface of the glass sample. As a result, the ion beam image becomes an image captured from a direction perpendicular to the surface of the glass sample. The ion beam image is, for example, a grayscale image in which the brightness of each pixel corresponds to the irradiation intensity of the ion beam IB.

[0059] Figure 7 shows ion beam image Ia before correction and ion beam image Ib after correction. Ion beam image Ia was captured by tilting the glass sample by 80°. Here, since 1 / sin(80°)=1.0154, ion beam image Ia is stretched by 1.0154 times in the vertical direction corresponding to the tilt direction of the glass sample. This allows ion beam image Ib to be obtained.

[0060] 1.2.3. Process for generating predicted images at each time point S30 (1) First time Next, a predicted image at a first time is generated. The first time is the time when processing starts. Figures 8 and 9 are diagrams for explaining the process of generating a predicted image at the first time.

[0061] First, as shown in Fig. 8, an ion beam image Ib is arranged at a position of distance B between the set rotation center RC and the center BC of the ion beam IB, and an irradiation intensity distribution image Ib-1 at a first time is generated. The irradiation intensity distribution image Ib-1 at the first time is an image showing the distribution of the irradiation intensity of the ion beam IB at the first time. In the irradiation intensity distribution image Ib-1 shown in Fig. 8, the irradiation intensity of the ion beam IB is represented by brightness.

[0062] Next, for each pixel of the irradiation intensity distribution image Ib-1 at the first time, vector component decomposition is performed, and a radial component image Ir-1 showing the intensity distribution of the radial component of the ion beam IB and an A rotational component image In-1 showing the intensity distribution of the component in the rotational direction of the on-beam IB is generated.

[0063] Specifically, first, in each pixel of the irradiation intensity distribution image Ib-1, the luminance S el The vector whose length is the size of the ion beam IB and whose direction is the irradiation direction of the ion beam IB is the radial component S el cosξ and the rotational component S el sinξ. Here, angle ξ is the angle between the radial direction and the irradiation direction of the ion beam at each pixel. In FIG. 9, the irradiation direction of the ion beam IB is indicated by arrow C. From the radial component of each pixel obtained in this way, a radial component image Ir-1 is generated, in which the magnitude of the radial component is expressed as brightness. Also, from the rotational component of each pixel, a rotational component image In-1 is generated, in which the magnitude of the rotational component is expressed as brightness.

[0064] Next, the radial component image Ir-1 and the rotational component image In-1 are superimposed to generate a vector component distribution image Irn-1 that indicates the distribution of the radial irradiation intensity and the rotational irradiation intensity of the ion beam at time 1. Specifically, for each corresponding pixel in the radial component image Ir-1 and the rotational component image In-1, the brightness value is added with the radial direction as positive and the rotational direction as negative.

[0065] For example, the radial component image Ir-1 is a 256-tone image, the rotational component image In-1 is a 256-tone image, and by adding them with the radial direction as plus and the rotational direction as minus, an image with 512 tones is generated. When this 512-tone image is output as an image with 256 tones, the luminance equivalent to zero is set to the intermediate 128th tone, and then normalized by the larger absolute value of the maximum and minimum values.

[0066] As a result, in the vector component distribution image Irn-1, areas brighter than the intermediate color indicate that the ion beam intensity in the radial direction is high, and areas darker than the intermediate color indicate that the ion beam intensity in the rotational direction is high. In this way, the irradiation intensity of the ion beam IB in the radial direction and the irradiation intensity of the ion beam IB in the rotational direction can be visualized. In the vector component distribution image Irn-1, it can be said that areas brighter than the intermediate color are prone to radial processing streaks, and areas darker than the intermediate color are prone to rotational processing streaks.

[0067] In this way, an illumination intensity distribution image Ib-1 and a vector component distribution image Irn-1 can be generated as predicted images at the first time point.

[0068] (2)Second time (2-1) Ion beam irradiation position (swing) Next, at a second time, the irradiation position of the ion beam IB moved by the swing of the sample S, that is, the position of the center BC, is obtained. The second time is a time after the first time. The second time is, for example, one second after the first time.

[0069] FIG. 10 is a diagram for explaining a method for calculating the irradiation position of the ion beam IB that has moved due to the swing of the sample at the second time.

[0070] First, a rotation angle β of the ion beam IB rotated by swinging the sample S between the first time and the second time is obtained. The rotation angle β can be obtained from the swing speed, the swing angle, and the elapsed time.

[0071] Next, the coordinates (xl, yl) of the center BC of the ion beam IB at the second time are calculated using the rotation angle β of the ion beam due to the swing, the distance D between the swing center SC and the rotation center RC, and the distance B between the rotation center RC and the center BC, and the calculation result is converted into a polar coordinate system to obtain the coordinates (r, θ1). The coordinates (r, θ1) of the center BC are calculated using the following formula: can be done.

[0072] x1=(D+B)sinβ y1=D-(D+B)cosβ r=(x1 2 +y1 2 ) 1 / 2 θ1=tan -1 (y1 / x1) Using these calculation formulas, the coordinates (r, θ1) of the center BC of the ion beam IB moved by the swing at the second time are obtained.

[0073] (2-2) Ion beam irradiation position (rotation) at the second time Next, the irradiation position of the ion beam IB moved by the rotation at the second time is calculated. Fig. 11 is a diagram for explaining a method of calculating the irradiation position of the ion beam IB moved by the rotation of the sample at the second time.

[0074] First, the rotation angle γ of the ion beam IB rotated by rotating the sample S between the first time and the second time is obtained. The rotation angle γ can be obtained from the rotation speed and the elapsed time.

[0075] Next, the coordinates (x2, y2) of the center BC of the ion beam IB at the second time are obtained. First, the rotation angle γ is added to the angle θ1 to obtain the coordinates of the center BC as (r, θ2), and then the coordinates (r, θ2) are converted to Cartesian coordinates (x2, y2). The rotation angle φ of the ion beam IB at the second time can be obtained by adding the rotation angles β and γ. The coordinates (x2, y2) of the center BC can be obtained by the following formula.

[0076] r=(x2 2 +y2 2 ) 1 / 2 θ2=θ1+γ φ=β+γ Using these calculation formulas, the coordinates (x2, y2) of the center BC of the ion beam IB at the second time are obtained.

[0077] (2-3) Decomposition of a vector Next, an ion beam image Ib is placed at the coordinates (x2, y2) of the center BC of the ion beam IB to generate an irradiation intensity distribution image Ib-2 at the second time. Next, for each pixel of the irradiation intensity distribution image Ib-2 at the second time, vector component decomposition is performed to generate a radial component image Ir-2 and a rotational component image In-2 at the second time.

[0078] FIG. 12 is a diagram for explaining component decomposition of a vector.

[0079] At the pixel with coordinates (x3, y3), the luminance S el A vector whose length is the size of and whose direction is the irradiation direction of the ion beam IB is separated into a radial component Sr and a rotational component Sn centered on the rotation center RC. At the second time, the radial component Sr and the rotational component Sn of the pixel at the coordinates (x3, y3) can be calculated by the following formula.

[0080] Ψ=tan -1 (y3 / x3) ξ=Ψ+(π / 2-φ) Sr=|S el cosξ| Sn=|S el sinξ| Using the above formula, the radial component Sr and the rotational component Sn can be calculated at the coordinates (x3, y3). Similarly, the radial component Sr and the rotational component Sn can be calculated for other pixels of the irradiation intensity distribution image Ib-2 using the above formula. This makes it possible to generate a radial component image Ir-2 and a rotational component image In-2.

[0081] Next, the radial component image Ir-2 and the rotational component image In-2 are superimposed to generate a vector component distribution image Irn-2 that indicates the distribution of the radial irradiation intensity and the rotational irradiation intensity of the ion beam at the second time. In this way, an irradiation intensity distribution image Ib-2 and a vector component distribution image Irn-2 can be generated as predicted images at the second time.

[0082] For each time point after the second time point until the end of the processing time, an irradiation intensity distribution image and a vector component distribution image are generated in the same manner as for the second time point.

[0083] 1.2.4. Addition process of predicted images at each time S40 The irradiation intensity distribution images at each time from the first time to the nth time after the processing time has elapsed are added together to generate an irradiation intensity distribution image showing the distribution of the irradiation intensity of the ion beam IB after the set processing time has elapsed. Specifically, the luminance values ​​of the corresponding pixels of the irradiation intensity distribution images from the first time to the nth time are added together to generate an irradiation intensity distribution image after the set processing time has elapsed. FIG. 13 shows an image showing the irradiation intensity distribution images from the first time to the 9th time superimposed. The interval between each time is 1 second.

[0084] Similarly, the vector component distribution images at each time from the first time to the nth time are added together to generate a vector component distribution image showing the distribution of the radial irradiation intensity of the ion beam IB and the distribution of the rotational irradiation intensity after the set processing time has elapsed.

[0085] Through the above steps, an irradiation intensity distribution image and a vector component distribution image can be generated as predicted images when the sample S is processed under the set processing conditions.

[0086] 1.3. Predicted Image 1.3.1. Irradiation intensity distribution image Fig. 14 is a diagram showing an irradiation intensity distribution image showing the distribution of the irradiation intensity of the ion beam IB on the sample S when the sample S is processed under the set processing conditions. Fig. 14 shows four irradiation intensity distribution images generated by changing the processing conditions.

[0087] Specifically, FIG. 14 shows an irradiation intensity distribution image obtained under the processing conditions of an irradiation angle α of the ion beam IB of 80° and no swing, an irradiation intensity distribution image obtained under the processing conditions of an irradiation angle α of 80° and a swing angle of -30° to +30°, an irradiation intensity distribution image obtained under the processing conditions of an irradiation angle α of 85° and no swing, and an irradiation intensity distribution image obtained under the processing conditions of an irradiation angle α of 85° and a swing angle of -30° to +30°. The other processing conditions are the same in each irradiation intensity distribution image. Note that in each irradiation intensity distribution image shown in FIG. 14, the brightness is normalized by the maximum brightness.

[0088] Fig. 15 is a graph showing the luminance profile of each irradiation intensity distribution image. The four luminance profiles shown in Fig. 15 are luminance profiles on the center line of each irradiation intensity distribution image shown in Fig. 14. In each luminance profile shown in Fig. 15, the current value of the ion beam is normalized by the total luminance of the irradiation intensity distribution image to convert it into a current density, and then multiplied by the component of the ion beam irradiated at the irradiation angle α in the depth direction of the sample as a coefficient. That is, the vertical axis of the graph shown in Fig. 15 corresponds to the processing depth.

[0089] From the four irradiation intensity distribution images shown in FIG. 14 and the four brightness profiles shown in FIG. 15, it can be seen that by swinging the sample S, a wider smooth area can be formed near the center of the sample S compared to the case where the sample S is not swung.

[0090] 1.3.2. Vector component distribution image Fig. 16 is a diagram showing vector component distribution images showing the distribution of the radial irradiation intensity and the rotational irradiation intensity of the ion beam IB on the sample S when the sample S is processed under the set processing conditions. Fig. 16 shows four vector component distribution images generated by changing the processing conditions.

[0091] The brightness of each vector component distribution image shown in Fig. 16 is normalized by the maximum brightness. In each vector component distribution image shown in Fig. 16, areas brighter than the intermediate color indicate that the ion beam irradiation intensity in the radial direction is high, and areas darker than the intermediate color indicate that the ion beam irradiation intensity in the rotational direction is high. In other words, areas brighter than the intermediate color are more likely to have radial processing streaks, and areas darker than the intermediate color are more likely to have rotational processing streaks.

[0092] Fig. 17 is a graph showing the luminance profile of each vector component distribution image. The four luminance profiles shown in Fig. 17 are luminance profiles on the center line of each vector component distribution image shown in Fig. 16. In each luminance profile shown in Fig. 17, if the intensity shown on the vertical axis is positive, it indicates that the irradiation intensity of the ion beam in the radial direction is high, and if the intensity shown on the vertical axis is negative, it indicates that the irradiation intensity of the ion beam in the rotational direction is high. In other words, if the intensity is positive, processing streaks in the radial direction are likely to occur, and if the intensity is negative, processing streaks in the rotational direction are likely to occur.

[0093] From the four vector component distribution images shown in Fig. 16 and the four brightness profiles shown in Fig. 17, when the sample S is not swung, the area formed near the center of the sample S where the ion beam is irradiated from both the rotational direction and the radial direction is narrow, and the irradiation intensity of the ion beam in the radial direction is high in areas other than the center. In other words, when the sample S is not swung, the area near the center of the sample S where processing streaks are unlikely to occur is narrow, and radial processing streaks are likely to occur in areas other than the center.

[0094] In contrast, when the sample S is swung, the region formed near the center of the sample S that is irradiated with the ion beam from both the rotational direction and the radial direction is wider than when the sample S is not swung, and the intensity of the ion beam is smaller in both the radial direction and the rotational direction in regions other than near the center. In other words, it can be seen that when the sample S is swung, a smooth region with less influence of processing streaks can be formed widely near the center of the sample S compared to when the sample S is not swung.

[0095] 1.3.3. Display method In the vector component distribution image shown in Fig. 16, the distribution of the irradiation direction of the ion beam IB is expressed by making the irradiation intensity of the ion beam IB in the radial direction brighter than the intermediate color and making the irradiation intensity of the ion beam in the rotational direction darker than the intermediate color. Note that the way of expressing the distribution of the irradiation direction of the ion beam IB is not limited to this.

[0096] For example, the distribution of the irradiation direction of the ion beam IB may be represented by color. Specifically, the irradiation intensity in the radial direction may be represented by cyan (green + blue), and the irradiation intensity in the rotational direction may be represented by red. In this display method, when the irradiation intensity in the radial direction and the irradiation intensity in the rotational direction are the same, the saturation disappears and becomes grayscale, so that the same information as the irradiation intensity distribution image can be shown in the vector component distribution image. That is, in this display method, the intensity distribution and the distribution of the irradiation direction of the ion beam IB can be expressed in one image. Note that the color combination is not limited to cyan and red, and may be a combination of magenta (red + blue) and green, or a combination of yellow (red + green) and blue.

[0097] 1.3.4. Correction of predicted images In the brightness profile shown in Fig. 15, the brightness of the irradiation intensity distribution image is corrected by the coefficients corresponding to the current density and the irradiation angle, but the brightness of the irradiation intensity distribution image may be corrected by the processing depth of a sample actually processed under the same processing conditions to create a brightness profile. This allows the vertical axis of the brightness profile to be represented by the processing depth.

[0098] In addition, since the milling rate differs depending on the energy of the ion beam and the material constituting the sample, the brightness of the irradiation intensity distribution image may be corrected according to the processing conditions and sample set by the user.

[0099] 1.4. Display In the image generating device 200, the display control unit 214 causes the display unit 230 to display the predicted image. The display control unit 214 causes the predicted image to be displayed in, for example, the predicted image display section G6 of the GUI screen 4 shown in FIG.

[0100] Fig. 18 is a diagram for explaining an example of a method for displaying a predicted image. As shown in Fig. 18, an image of the sample S before processing and a vector component distribution image are displayed in an overlapping manner. Furthermore, the position indicated by the horizontal axis of the brightness profile is displayed in accordance with the position of the image of the sample S. The image of the sample S before processing is an image captured by, for example, an alignment camera 130 or a processing and observation camera 140.

[0101] In the example shown in Fig. 18, the vertical axis of the luminance profile is converted into processing depth. In addition, the luminance profile shown in Fig. 18 displays the processing depth profile and the radial component profile.

[0102] Fig. 19 is a diagram for explaining an example of a method for displaying a predicted image. In the example shown in Fig. 19, an image of the sample S before processing and the left half of the vector component distribution image are displayed in an overlapping manner.

[0103] Fig. 20 is a diagram for explaining an example of a method for displaying a predicted image. In the example shown in Fig. 20, an image of the processed sample S and a vector component distribution image are displayed in an overlapping manner. In the example shown in Fig. 20, an image of the processed sample S and the left half of the vector component distribution image are displayed in an overlapping manner. Furthermore, a luminance profile is displayed by aligning the position indicated by the horizontal axis of the luminance profile with the position of the image of the sample S.

[0104] Fig. 21 is a diagram for explaining an example of a method for displaying a predicted image. In the example shown in Fig. 21, the brightness of the irradiation intensity distribution image is corrected to the processing depth, and is displayed as a three-dimensional graph showing the position on the sample S and the processing depth at that position.

[0105] Fig. 22 is a diagram for explaining an example of a method for displaying a predicted image. In the example shown in Fig. 22, both an image of the sample S before processing and a vector component distribution image superimposed thereon, and a three-dimensional graph showing positions on the sample S and processing depths at those positions are displayed.

[0106] 1.5. Image generation process FIG. 23 is a flowchart showing an example of the image generation process of the image generation device 200.

[0107] First, the image generating unit 212 acquires information on the set processing conditions (S100). The processing conditions are set, for example, by inputting the processing conditions into the GUI screen 4. The image generating unit 212 acquires information on the processing conditions input by the user into the GUI screen 4 via the input unit 220. The image generating unit 212 may acquire information on the processing conditions from the control unit 170.

[0108] The processing conditions are the energy of the ion beam IB (acceleration voltage of the ion beam), The processing conditions include the irradiation angle α of the ion beam IB, the rotation speed of the sample S, the swing angle range of the sample S, the swing speed of the sample S, the distance B between the rotation center RC of the sample S and the center BC of the ion beam IB, the distance D between the rotation center RC of the sample S and the swing center SC, and the processing time. The processing condition information is stored in the storage unit 240.

[0109] Next, the image generating unit 212 acquires information on the ion beam IB (S102). The image generating unit 212 acquires, as the information on the ion beam IB, for example, an ion beam image Ib shown in FIG.

[0110] Next, the image generating unit 212 generates a predicted image at the first time based on the processing conditions and the information of the ion beam IB (S104). The image generating unit 212 generates an irradiation intensity distribution image Ib-1 and a vector component distribution image Irn-1 as predicted images at the first time by the method described in the above-mentioned step S30.

[0111] Next, the image generating unit 212 generates a predicted image at the mth time based on the processing conditions (S106). Here, m=2, and the image generating unit 212 generates a predicted image at the second time. The image generating unit 212 generates an irradiation intensity distribution image Ib-2 and a vector component distribution image Irn-2 as predicted images at the second time by the method described in the above-mentioned step S30.

[0112] Next, the image generating unit 212 adds the predicted image at the first time and the predicted image at the second time (S108). Specifically, the irradiation intensity distribution image Ib-1 and the irradiation intensity distribution image Ib-2 are added, and the vector component distribution image Irn-1 and the vector component distribution image Irn-2 are added. This makes it possible to generate a predicted image when processed from the first time to the second time.

[0113] Next, the image generating unit 212 determines whether or not a predicted image at the nth time has been generated (S110).

[0114] If the image generating unit 212 determines that a predicted image at the nth time has not been generated (No in S110), it sets m=2+1=3, returns to process S106, and generates a predicted image at the third time (S106). Then, the image generating unit 212 adds the predicted image at the third time to the predicted image obtained when the first time is processed to the second time (S108). This allows the generation of a predicted image obtained when the first time is processed to the third time.

[0115] The image generation unit 212 repeats the process of generating a predicted image at the mth time (S106), the process of adding the predicted image at the mth time and the predicted image processed from the 1st time to the m-1st time (S108), and the process of determining whether or not the predicted image at the nth time has been generated (S110), until the predicted image at the nth time is generated.

[0116] When it is determined that the image generating unit 212 has generated a predicted image at the nth time (Yes in S110), the display control unit 214 causes the display unit 230 to display the generated predicted image. The display control unit 214 causes the predicted image display section G6 of the GUI screen 4 to display the predicted image in any one of the display methods shown in Figs. 14 to 22 described above, for example. Note that the display control unit 214 may cause the display unit 230 to display the predicted image in a display method selected by the user from among the display methods shown in Figs. 14 to 22.

[0117] By the above processing, a predicted image of the sample when it is processed under the set processing conditions can be displayed.

[0118] 1.6. Effects The sample processing system 2 includes a sample processing device 100 that processes the sample S by irradiating the sample S with an ion beam IB, and an image generating device 200 that generates a predicted image when the sample S is processed under set processing conditions using the sample processing device 100. Therefore, in the sample processing system 2, a predicted image when the sample S is processed under the set processing conditions can be obtained, so that appropriate processing conditions can be easily determined.

[0119] Furthermore, in the sample processing system 2, the generated predicted image includes information on the distribution of the irradiation direction of the ion beam IB. Therefore, it is possible to predict in which region and in which direction processing streaks will be formed in the sample S by processing. For example, in a region of the sample S where the ion beam IB is irradiated only from one direction, processing streaks may be formed along the irradiation direction of the ion beam IB.

[0120] In the sample processing system 2, the sample processing device 100 includes an ion source 110 that irradiates the sample S with an ion beam IB, and a sample stage 120 that has a tilt mechanism 20 that tilts the sample S and a rotation mechanism 22 that rotates the sample S, and the processing conditions include the tilt angle and rotation speed of the sample S. Therefore, in the sample processing system 2, a predicted image that takes into account the tilt angle and rotation speed can be generated, so that the tilt angle conditions of the sample S and the rotation speed conditions of the sample S can be easily determined.

[0121] In the sample processing system 2, the sample stage 120 has a swing mechanism 24 that swings the sample S, the swing center SC of the sample S and the rotation center RC of the sample S are at different positions, and the processing conditions include a distance D between the rotation center RC and the swing center SC. Therefore, in the sample processing system 2, the sample S can be swung while rotating, so that the area on the surface Sa of the sample S that is irradiated with the ion beam IB can be expanded. Furthermore, the area on the surface Sa of the sample S that is irradiated with the ion beam IB from multiple directions can be expanded. Also, in the sample processing system 2, a predicted image that takes the distance D into consideration can be generated, so that the conditions for the distance D can be easily determined.

[0122] In addition, in the sample processing system 2, the distance D between the rotation center RC of the sample S and the swing center SC of the sample S is variable. In the sample processing system 2, a predicted image can be generated taking the distance D into consideration, so that the conditions for the distance D can be easily determined.

[0123] In the sample processing system 2, the distance between the center BC of the ion beam IB on the sample S and the center of rotation RC of the sample S is variable, and the processing conditions include the distance B between the center BC and the center of rotation RC. Therefore, in the sample processing system 2, it is possible to expand the area on the surface Sa of the sample S that is irradiated with the ion beam IB. Furthermore, in the sample processing system 2, a predicted image that takes the distance B into consideration can be generated, so that the condition of the distance B can be easily determined.

[0124] In the sample processing system 2, the image generating device 200 calculates the irradiation direction of the ion beam IB at each time during processing based on the processing conditions, and generates a predicted image based on the irradiation direction of the ion beam IB at each time. Therefore, in the sample processing system 2, a predicted image including information on the distribution of the irradiation directions of the ion beam IB can be generated.

[0125] In the sample processing system 2, the image generating device 200 separates a vector representing the irradiation direction and irradiation intensity of the ion beam IB at each time into a radial component and a rotational component centered on the rotation center RC of the sample S. Furthermore, the image generating device 200 generates a predicted image including information on the radial distribution of the intensity of the ion beam IB and information on the distribution of the intensity of the ion beam IB in the rotational direction based on the radial component at each time and the rotational component at each time. Therefore, in the sample processing system 2, it is possible to determine from the predicted image the areas on the surface Sa of the sample S where radial processing streaks are likely to occur and the areas in the rotational direction where radial processing streaks are likely to occur. This allows you to know the areas where processing streaks are likely to occur.

[0126] In the sample processing system 2, the image generating device 200 displays the predicted image superimposed on the image of the sample S before processing. Therefore, in the sample processing system 2, it is possible to easily display which area of ​​the sample S will be processed and how.

[0127] In the sample processing system 2, the image generating device 200 displays the irradiation direction of the ion beam in a color in the predicted image. Therefore, the image generating device 200 can easily display the distribution of the irradiation directions of the ion beam in the predicted image.

[0128] In the sample processing system 2, the predicted image includes information on the distribution of the irradiation intensity of the ion beam. Therefore, in the sample processing system 2, it is possible to know which region of the sample S will be processed to what depth when the sample S is processed under the set processing conditions.

[0129] In the sample processing system 2, the predicted image includes information on the distribution of irradiation intensity of the ion beam IB in the radial direction around the rotation center RC of the sample S, and information on the distribution of irradiation intensity of the ion beam IB in the rotation direction around the rotation center RC of the sample S. Therefore, in the sample processing system 2, when the sample S is processed under the set processing conditions, it is possible to know the area on the surface Sa of the sample S where radial processing streaks are likely to occur and the area where rotational processing streaks are likely to occur.

[0130] The image generating device 200 includes an image generating unit 212 that generates a predicted image when the sample S is processed under set processing conditions using the sample processing device 100 that processes the sample S by irradiating the sample S with an ion beam, and a display control unit 214 that displays the predicted image. The predicted image also includes information on the distribution of the irradiation direction of the ion beam IB. Therefore, the image generating device 200 can generate a predicted image when the sample S is processed under the set processing conditions, and therefore the processing conditions can be easily determined.

[0131] The image generating method in the sample processing system 2 includes a step of generating a predicted image of the sample S when it is processed under set processing conditions using a sample processing device 100 that processes the sample S by irradiating the sample S with an ion beam IB, and a step of displaying the predicted image. The predicted image also includes information on the distribution of the irradiation direction of the ion beam IB. Therefore, the image generating method in the sample processing system 2 can obtain a predicted image of the sample S when it is processed under the set processing conditions, so that appropriate processing conditions can be easily determined.

[0132] 2. Second embodiment Next, the sample processing system according to the second embodiment will be described with reference to the drawings. Fig. 24 is a diagram showing the configuration of the ion source 110 of the sample processing system according to the second embodiment. In the sample processing system according to the second embodiment, members having the same functions as those of the sample processing system 2 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0133] The ion source 110 is a Penning type ion source, and includes an anode 11, a cathode 12, an extraction electrode 13, and a focus electrode 14, as shown in FIG.

[0134] The anode 11 is cylindrical. The space inside the anode 11 serves as an ionization chamber for generating ions. Although not shown, gas is introduced into the ionization chamber from a gas supply unit. The gas introduced into the ionization chamber is, for example, argon gas.

[0135] The cathode 12 emits electrons. The cathode 12 also constitutes a pole piece that generates a magnetic field in the ionization chamber. The electrons emitted from the cathode 12 undergo a rotational motion due to the magnetic field generated by the pole piece. A discharge voltage is applied between the anode 11 and the cathode 12 to cause a discharge.

[0136] The extraction electrode 13 extracts the ions generated in the ionization chamber. The ions are accelerated by the electric field created by the extraction electrode 13 and are emitted as an ion beam IB from the ion source 110. An acceleration voltage for accelerating the ions is applied between the anode 11 and the extraction electrode 13.

[0137] The focus electrode 14 is disposed between the cathode 12 and the extraction electrode 13. The focus electrode 14 is an electrode for controlling the spatial profile of the ion beam IB. Here, the spatial profile of the ion beam IB refers to the spatial intensity distribution of the ion beam IB.

[0138] In the ion source 110, an ion beam IB with uniform intensity can be obtained by controlling the focus voltage applied to the focus electrode 14. That is, the ion source 110 can emit an ion beam IB with a spatial profile close to that of a parallel beam.

[0139] In the sample processing system 2, the processing conditions include a discharge voltage, a focus voltage, and a flow rate of a gas introduced into the ionization chamber.

[0140] FIG. 25 is an example of a predicted image generated by the sample processing system 2 according to the second embodiment.

[0141] In the ion source 110, an ion beam IB with uniform intensity can be obtained, so that a wide area in the center of the sample S can be flattened and a wide range can be milled, as shown in FIG.

[0142] FIG. 26 is a schematic diagram showing the state of plane milling of sample S having a laminated structure. When plane milling sample S, flat milled regions and tapered milled regions are formed in sample S. Regions A and A' shown in FIG. 26 are milled flat. In contrast, regions B and B' are milled tapered. Regions B and B' have different taper angles, and therefore the amount of information obtained differs. Specifically, region B' has a smaller taper angle than region B, and therefore the state of each layer can be confirmed.

[0143] FIG. 27 is an example of a predicted image generated by the sample processing system 2 according to the second embodiment.

[0144] FIG. 27 shows luminance profiles P1, P2, P3, and P4. The luminance profile P1 is a luminance profile obtained under the processing conditions of making the intensity of the ion beam IB uniform using the focus electrode 14, setting the irradiation angle α of the ion beam IB to 80°, and not swinging. The luminance profile P2 is a luminance profile obtained under the processing conditions of making the intensity of the ion beam IB uniform using the focus electrode 14, setting the irradiation angle α of the ion beam IB to 80°, and setting the swing angle to -30° to +30°. The luminance profile P3 is a luminance profile obtained as a comparative example under the processing conditions of not using a focus electrode, setting the irradiation angle α of the ion beam IB to 80°, and not swinging. The luminance profile P4 is a luminance profile obtained as a comparative example under the processing conditions of not using a focus electrode, setting the irradiation angle α of the ion beam IB to 80°, and setting the swing angle to -30° to +30°.

[0145] The difference in the tapered region can be seen from the luminance profile shown in Fig. 27. Specifically, it can be seen that under the processing conditions of the luminance profile P2, the taper angle becomes smaller as in region B'.

[0146] 3. Third embodiment Next, a sample processing system according to a third embodiment will be described with reference to the drawings. Figures 28 and 29 are diagrams showing the configuration of a sample processing system 2 according to the third embodiment. In the sample processing system according to the third embodiment, members having the same functions as those of the sample processing system 2 according to the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

[0147] As shown in FIGS. 28 and 29, the sample processing apparatus 100 includes an ion source moving mechanism 180 that moves the ion source 110 in the Z direction.

[0148] The ion source moving mechanism 180 moves the ion source 110 in the Z direction. By moving the ion source 110 in the Z direction with the ion source moving mechanism 180, the distance between the ion source 110 and the sample S can be adjusted. In Fig. 28, the ion source 110 is moved in the +Z direction, and in Fig. 29, the ion source 110 is moved in the -Z direction.

[0149] Fig. 30 is a diagram for explaining the relationship between the distance D between the rotation center RC and the swing center SC of the sample S and the irradiation range of the ion beam IB. As shown in Fig. 30, the irradiation range W of the ion beam IB can be increased as the distance D is increased.

[0150] However, when the sample S is moved in the -Z direction using the Z stage 26 to increase the distance D while the ion source 110 is fixed, the distance between the ion source 110 and the sample S increases. This reduces the irradiation intensity of the ion beam IB, and the processing rate decreases.

[0151] In the sample processing system 2, when the sample S is moved in the -Z direction by the Z stage 26 to increase the distance D, the ion source 110 can be moved in the -Z direction by the same distance by the ion source moving mechanism 180. This allows the distance D to be increased without changing the distance between the sample S and the ion source 110.

[0152] As described above, in the sample processing system 2, the sample processing device 100 includes the ion source moving mechanism 180 that moves the ion source 110, so that the distance D can be changed without changing the distance between the sample S and the ion source 110.

[0153] 4. Fourth embodiment Next, a sample processing system according to a fourth embodiment will be described with reference to the drawings. Figures 31 and 32 are diagrams showing the configuration of a sample processing system 2 according to the fourth embodiment. In the sample processing system according to the fourth embodiment, members having the same functions as those of the sample processing system 2 according to the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

[0154] In the sample processing system 2 according to the third embodiment described above, as shown in Figures 29 and 30, the sample processing apparatus 100 includes an ion source moving mechanism 180, so that the distance D can be changed without changing the distance between the sample S and the ion source 110.

[0155] In contrast, in the sample processing system 2 according to the fourth embodiment, as shown in FIGS. 31 and 32, the sample processing device 100 includes a swing movement mechanism 190 for moving the swing mechanism 24. Therefore, the distance D can be changed without changing the distance between the sample S and the ion source 110.

[0156] The swing movement mechanism 190 includes the chamber door 160 to which the swing mechanism 24 is attached, and a flange 192 that movably supports the chamber door 160. The flange 192 is fixed to the chamber 150.

[0157] As shown in Figures 31 and 32, the chamber door 160 is movable in the Z direction. For example, by moving the chamber door 160 in the +Z direction, the swing mechanism 24 moves in the +Z direction. This makes it possible to increase the distance D between the rotation center RC and the swing center SC of the sample S. At this time, the Z stage 26 is used to move the sample S in the -Z direction by the same distance as the swing mechanism 24. This makes it possible to increase the distance D without changing the distance between the sample S and the ion source 110.

[0158] In this manner, since the sample processing system 2 includes the swing movement mechanism 190 that moves the swing mechanism 24, the distance D can be changed without changing the distance between the sample S and the ion source 110.

[0159] 5. Fifth embodiment Next, the sample processing system according to the fifth embodiment will be described with reference to the drawings. Figures 33 and 34 are diagrams showing the configuration of the sample processing system 2 according to the fifth embodiment. In the sample processing system according to the fifth embodiment, members having the same functions as those of the sample processing system 2 according to the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

[0160] In the sample processing system 2, as shown in Figures 33 and 34, the swing mechanism 24 includes a swing table 24a and a driving device 24b that swings the swing table 24a. The swing mechanism 24 is disposed in a chamber 150. The swing mechanism 24 is disposed on an XY stage 28.

[0161] The driving device 24b is movable on the XY stage 28, and the axis B serving as the swing axis can be moved by moving the driving device 24b. This makes it possible to adjust the distance between the ion source 110 and the axis B. The driving device 24b includes, for example, a vacuum compatible motor.

[0162] A tilt mechanism 20 is disposed on the swing table 24a, and a rotation mechanism 22 to which a sample S is fixed is disposed on the tilt mechanism 20. The tilt mechanism 20 is configured to be movable in the Y direction on the swing table 24a. By moving the tilt mechanism 20 in the Y direction, the distance between the ion source 110 and the sample S can be adjusted. In the sample processing system 2, the ion source 110 is attached to a side wall on the -Y side in the chamber 150.

[0163] For example, by moving the driving device 24b of the swing mechanism 24 in the -Y direction, the axis B serving as the swing axis is moved in the -Y direction, and the distance D between the swing center SC and the rotation center RC is increased. At this time, the sample S is moved in the +Y direction by the same distance as the axis B using the XY stage 28. This makes it possible to increase the distance D without changing the distance between the sample S and the ion source 110.

[0164] In this manner, in the sample processing system 2, since the swing mechanism 24 is movable in the Y direction, the distance D can be changed without changing the distance between the sample S and the ion source 110.

[0165] 6. Sixth embodiment 6.1. Sample processing system Next, a sample processing system according to a sixth embodiment will be described with reference to the drawings. The configuration of the sample processing system according to the sixth embodiment is the same as that of the sample processing system 2 according to the first embodiment shown in Fig. 1 and Fig. 2, and therefore the description thereof will be omitted.

[0166] 6.2. Image Generation Method In the sample processing system 2 according to the first embodiment described above, the image generating device 200 generated, as predicted images, the irradiation intensity distribution image shown in Figures 14 and 15, and the vector component distribution image of the ion beam IB shown in Figures 16 and 17.

[0167] In contrast to this, the image generating device 200 may generate, as a predicted image, an irradiation direction distribution image that shows only the distribution of the irradiation directions of the ion beam IB.

[0168] Fig. 35 to Fig. 37 are diagrams showing an example of an irradiation direction distribution image, each of which shows a diagram for explaining processing conditions and an irradiation direction distribution image.

[0169] Fig. 35 is an irradiation direction distribution image when processing is performed under processing conditions where the center RC of the rotation and the center BC of the ion beam IB are aligned. Fig. 36 is an irradiation direction distribution image when processing is performed under processing conditions where the center RC of the rotation and the center BC of the ion beam IB are aligned and the center RC of the rotation and the swing center SC are shifted. Fig. 37 is an irradiation direction distribution image when processing is performed under processing conditions where the center RC of the rotation and the center BC of the ion beam IB are shifted and the center RC of the rotation and the swing center SC are shifted.

[0170] From the irradiation direction distribution images shown in Figures 35 to 37, it can be seen that by shifting the center BC of the ion beam IB from the rotation center RC and also shifting the center BC of the ion beam IB from the rotation center RC and the swing center SC, the area irradiated with the ion beam IB from multiple directions can be expanded.

[0171] 6.3. Image generation process The image generation process of the image generating device 200 will be described with reference to the flowchart shown in Fig. 23. The process of generating an irradiation direction distribution image will be described below. Note that the description of the same points as those in the image generating process described above will be omitted.

[0172] First, the image generating unit 212 acquires information on processing conditions (S100).

[0173] Next, the image generating unit 212 acquires information on the ion beam IB (S102). The image generating unit 212 acquires an ion beam image Ib shown in FIG. 7 as information on the ion beam IB. Note that, in this case, it is sufficient to acquire information on the diameter of the beam in the ion beam image Ib. Therefore, if information on the diameter of the ion beam IB is acquired as a processing condition, it is not necessary to acquire the ion beam image Ib.

[0174] Next, the image generating unit 212 generates an irradiation direction distribution image at the first time as a predicted image at the first time based on the processing conditions and the information on the ion beam IB (S104).

[0175] Fig. 38 is a diagram showing a schematic diagram of an irradiation direction distribution image I-1 at a first time. As shown in Fig. 38, in the irradiation direction distribution image I-1, an arrow indicating the irradiation direction of the ion beam IB at a first time is drawn inside the outline of the ion beam IB. In this manner, the irradiation direction distribution image I-1 includes information on the irradiation direction of the ion beam IB but does not include information on the irradiation intensity of the ion beam IB.

[0176] Next, the image generating unit 212 generates an irradiation direction distribution image at the mth time based on the processing conditions (S106).

[0177] 39 is a diagram illustrating an example of an irradiation direction distribution image I-2 at the second time. The irradiation position and irradiation direction of the ion beam IB at the second time can be calculated in the same manner as in step S106 in the first embodiment described above.

[0178] Next, the image generating unit 212 adds the irradiation direction distribution image I-1 and the irradiation direction distribution image I-2 (S108). For example, the irradiation direction distribution image I-1 and the irradiation direction distribution image I-2 are superimposed. Next, the image generating unit 212 determines whether or not a predicted image at the nth time has been generated (S110).

[0179] The image generating unit 212 repeats the process S106 of generating an irradiation direction distribution image at the mth time, the process S108 of adding the irradiation direction distribution image at the mth time and the irradiation direction distribution image processed from the 1st time to the (m-1)th time, and the process S110 of determining whether or not the irradiation direction distribution image at the nth time has been generated, until generating an irradiation direction distribution image at the nth time.

[0180] When it is determined that the image generating unit 212 has generated an irradiation direction distribution image at the nth time (Yes in S110), the display control unit 214 causes the generated irradiation direction distribution image to be displayed on the display unit 230. The display control unit 214 causes the display unit 230 to display an irradiation direction distribution image in which the irradiation directions are represented by arrows, as shown in, for example, Figs. 35 to 37. Note that the method of displaying the irradiation directions is not particularly limited, and for example, the irradiation directions may be represented by colors.

[0181] By the above processing, it is possible to display an irradiation direction distribution image when the sample is processed under the set processing conditions.

[0182] Effect In the sample processing system 2 of the sixth embodiment, the predicted image includes information on the distribution of the irradiation direction of the ion beam IB irradiated during processing, so that, similar to the sample processing system 2 of the first embodiment, it is possible to predict in which area and in which direction the processing lines formed in the sample S by processing will occur.

[0183] 7. Other The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the present invention.

[0184] In the above-mentioned first to sixth embodiments, the sample processing apparatus 100 has been described as rotating the sample S and swinging the sample S, but the operation of the sample processing apparatus 100 is not limited to this. For example, the sample processing apparatus 100 may slide the sample S along one axis perpendicular to the optical axis of the ion beam IB while rotating the sample S. Also, for example, the sample processing apparatus 100 may move the sample S along the X-axis and Y-axis perpendicular to the optical axis of the ion beam IB to scan the surface Sa of the sample S with the ion beam IB.

[0185] 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 appropriately combined.

[0186] The present invention is not limited to the above-described embodiment, and various modifications are possible. For example, the present invention includes a configuration that is substantially the same as the configuration described in the embodiment. A substantially identical configuration means, for example, a configuration that has the same function, method, and result, or a configuration that has 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 as the configurations described in the embodiments or that can achieve the same purpose. The present invention also includes configurations in which publicly known technology is added to the configurations described in the embodiments. [Explanation of symbols]

[0187] 2...sample processing system, 4...GUI screen, 6...slider, 8...checkbox, 11...anode, 12...cathode, 13...extraction electrode, 14...focus electrode, 20...tilt mechanism, 22...rotation mechanism, 24...swing mechanism, 24a...swing table, 24b...driver, 26...Z stage, 28...XY stage, 100...sample processing device, 110...ion source, 112...ion source control circuit, 120...sample stage, 130...alignment camera, 140...processing observation camera, 150...chamber, 160...chamber door, 162...observation window, 170...control unit, 180...ion source movement mechanism, 190...swing movement mechanism, 192...flange, 200...image generating device, 210...processing unit, 212...image generating unit, 214...display control unit, 220...input unit, 230...display unit, 240...storage unit

Claims

1. a sample processing device that processes a sample by irradiating the sample with an ion beam; an image generating device that generates a predicted image of the sample when the sample is processed under set processing conditions using the sample processing device; Including, A sample processing system, wherein the predicted image includes information on the distribution of the irradiation direction of the ion beam.

2. In claim 1, The sample processing device includes: an ion source for irradiating the sample with the ion beam; a sample stage having a tilt mechanism for tilting the sample and a rotation mechanism for rotating the sample; Including, A sample processing system, wherein the processing conditions include a tilt angle of the sample and a rotation speed of the sample.

3. In claim 2, the sample stage has a swing mechanism for swinging the sample, the swing center of the sample and the rotation center of the sample are at different positions; A sample processing system, wherein the processing conditions include a distance between a center of rotation of the sample and a center of swing of the sample.

4. In claim 3, A sample processing system, wherein the distance between the center of rotation of the sample and the center of swing of the sample is variable.

5. In claim 2, a distance between a center of the ion beam on the sample and a center of rotation of the sample is variable; A sample processing system, wherein the processing conditions include a distance between a center of the ion beam and a center of rotation of the sample.

6. In any one of claims 2 to 5, The image generating device comprises: Calculating the irradiation direction of the ion beam at each time during processing based on the processing conditions; A sample processing system that generates the predicted image based on the irradiation direction of the ion beam at each of the times.

7. In claim 6, The image generating device comprises: At each time, a vector representing the irradiation direction of the ion beam and the irradiation intensity of the ion beam is separated into a radial component and a rotational component with the center of rotation of the sample as a center; A sample processing system that generates the predicted image including information on the distribution of intensity of the ion beam in the radial direction and information on the distribution of intensity of the ion beam in the rotational direction based on the radial component at each time and the rotational component at each time.

8. In any one of claims 1 to 5, A sample processing system in which the image generating device displays the predicted image superimposed on an image of the sample before processing.

9. In any one of claims 1 to 5, A sample processing system, wherein the image generating device represents the irradiation direction of the ion beam in the predicted image with a color.

10. In any one of claims 1 to 5, A sample processing system, wherein the predicted image includes information on the distribution of irradiation intensity of the ion beam.

11. In any one of claims 2 to 5, A sample processing system, wherein the predicted image includes information on the distribution of irradiation intensity of the ion beam in a radial direction around the center of rotation of the sample, and information on the distribution of irradiation intensity of the ion beam in a rotational direction around the center of rotation of the sample.

12. an image generating unit that generates a predicted image of a sample when the sample is processed under set processing conditions using a sample processing device that processes the sample by irradiating the sample with an ion beam; a display control unit that displays the predicted image; Including, An image generating apparatus, wherein the predicted image includes information on the distribution of the irradiation direction of the ion beam.

13. A step of generating a predicted image of a sample when the sample is processed under set processing conditions using a sample processing device that processes the sample by irradiating the sample with an ion beam; displaying the predicted image; Including, An image generating method, wherein the predicted image includes information on the distribution of the irradiation direction of the ion beam.

Images