Sample analysis method and sample analysis device

Abstract

To analyze the internal state of a sample with high accuracy.SOLUTION: A load acting upon a cutting-edge in a direction X is measured while cutting a sample in the direction X in a first X-direction cutting step following a first Z-direction cutting step. The load acting upon the cutting-edge in the direction X is measured while cutting the sample in the direction X in a second X-direction cutting step following a second Z-direction cutting step. The first round of the second Z-direction cutting step involves cutting the sample to a position downward in the direction Z from the cutting position in the first X-direction cutting step. The second and subsequent rounds of the second Z-direction cutting step involves cutting the sample to a position downward in the direction Z from the cutting position of the second X-direction cutting step carried out immediately before. The internal state of the sample is analyzed on the basis of the load in the direction X measured in the first and second X-direction cutting steps.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a sample analysis method and a sample analysis device for analyzing the internal state of a sample. [Background technology]

[0002] In lithium batteries, if the distribution of components inside the electrode becomes uneven, the performance will decrease. Patent Document 1 discloses a method for analyzing the internal state of an electrode using a cutting device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-137005 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, there has been a demand for analyzing the internal state of a sample with higher precision.

[0005] An object of the present invention is to provide a sample analysis method and a sample analysis device that can analyze the internal state of a sample with high precision. [Means for solving the problem]

[0006] To achieve the above object, the present invention provides a sample analysis method for analyzing the internal state of a sample using a cutting device. The cutting device includes a cutting blade, a sample stage for fixing the sample, and a drive unit for moving the cutting blade and the sample stage relatively. The cutting blade and the sample stage are movable relative to each other in X and Y directions that are parallel to the surface of the sample and perpendicular to each other, and in Z direction that is perpendicular to the surface of the sample.

[0007] The sample analysis method according to the present invention includes a first Z-direction cutting step, a first X-direction cutting step, a second Z-direction cutting step, and a second X-direction cutting step. In the first Z-direction cutting step, the cutting blade is moved downward in the Z direction or downward in the Z direction and forward in the X direction relative to the sample stage to cut the surface of the sample. In the first X-direction cutting step, following the first Z-direction cutting step, the cutting blade is moved forward in the X direction relative to the sample stage to cut the sample, while measuring the load in the X direction applied to the cutting blade. In the second Z-direction cutting step, after the first X-direction cutting step, the cutting blade is moved downward in the Z direction or downward in the Z direction and forward in the X direction relative to the sample stage to cut the sample. In the second X-direction cutting step, following the second Z-direction cutting step, the cutting blade is moved forward in the X-direction relative to the sample stage, thereby cutting the sample and measuring the load in the X-direction acting on the cutting blade.

[0008] The second Z-direction cutting step and the second X-direction cutting step are each performed at least once. In the first second Z-direction cutting step, the sample is cut to a position in the Z direction lower than the cutting position in the first X-direction cutting step. In the second and subsequent second Z-direction cutting steps, the sample is cut to a position in the Z direction lower than the cutting position in the second X-direction cutting step performed immediately before.

[0009] The sample analysis method according to the present invention further includes an analysis step of analyzing an internal state of the sample based on the loads in the X direction measured in the first X direction cutting step and the second X direction cutting step.

[0010] According to the sample analysis method of the present invention described above, the load in the X direction acting on the cutting blade is measured while cutting by moving the cutting blade in the X direction relative to the sample in the first and second X direction cutting steps, so that the load in the X direction at different depths (positions in the Z direction) in the sample can be determined with high accuracy. Therefore, the measured value of the load in the X direction can be used to analyze the internal state of the sample three-dimensionally with high accuracy.

[0011] In the sample analysis method according to the present invention, the cutting ranges in the X direction and the Y direction may include the same region in each of the first X-direction cutting step and the second X-direction cutting step. In this way, the state of a specific three-dimensional region inside the sample can be analyzed with high precision using the load measurement value in the X direction.

[0012] In the sample analysis method according to the present invention, if the second Z-direction cutting step is performed once, the second Z-direction cutting step may start from the cutting surface of the first Z-direction cutting step or the first X-direction cutting step, and if the second Z-direction cutting step is performed two or more times, the second Z-direction cutting step performed later may start from the cutting surface of the second Z-direction cutting step or the second X-direction cutting step performed immediately before. In this way, the cutting distance is shorter than when cutting is started from the sample surface in each second Z-direction cutting step, and the time required for analysis can be significantly reduced.

[0013] In the sample analysis method according to the present invention, the analysis step may include a first analysis step of calculating an average value of the X-direction loads measured in the same specific section in the X direction in the first X-direction cutting step and the second X-direction cutting step, and a second analysis step of analyzing the internal state of the sample by comparing the average values ​​of the X-direction loads calculated in the first analysis step with each other. In this way, the internal state of the sample can be analyzed with higher accuracy using the average values ​​of the X-direction loads at different depths (Z-direction positions) in the sample.

[0014] In the sample analysis method according to the present invention, the sample may be a battery electrode, which allows the internal state of the battery electrode to be analyzed three-dimensionally with high precision.

[0015] The sample analyzer according to the present invention is a sample analyzer for analyzing the internal state of a sample, and includes a cutting blade, a sample stage for fixing the sample, a drive unit for moving the cutting blade and the sample stage relatively, a control unit for controlling the drive of the drive unit, and an analysis unit for analyzing the internal state of the sample. The cutting blade and the sample stage are movable relatively in X and Y directions that are parallel to the surface of the sample and perpendicular to each other, and in Z direction that is perpendicular to the surface of the sample.

[0016] The control unit is programmed with a first command, a second command, a third command, and a fourth command. The first command causes a first Z-direction cutting step to be performed in which the cutting blade is moved downward in the Z direction or downward in the Z direction and forward in the X direction relative to the sample stage to cut the surface of the sample. The second command causes a first X-direction cutting step to be performed, following the first Z-direction cutting step, in which the load on the cutting blade in the X direction is measured while cutting the sample by moving the cutting blade forward in the X direction relative to the sample stage. The third command causes a second Z-direction cutting step to be performed at least once after the first X-direction cutting step, in which the cutting blade is moved downward in the Z direction or downward in the Z direction and forward in the X direction relative to the sample stage to cut the sample. The fourth command causes a second X-direction cutting step to be performed at least once following the second Z-direction cutting step, in which the cutting blade is moved forward in the X-direction relative to the sample stage to cut the sample while measuring the load on the cutting blade in the X-direction.

[0017] The third command includes a command to cut the sample in the first second Z-direction cutting step to a position lower in the Z direction than the cutting position in the first X-direction cutting step, and to cut the sample in the second or subsequent second Z-direction cutting steps to a position lower in the Z direction than the cutting position in the second X-direction cutting step that was performed immediately before.

[0018] The analysis unit analyzes the internal state of the sample based on the load in the X direction measured in the first X direction cutting step and the second X direction cutting step.

[0019] According to the sample analyzer of the present invention described above, the load in the X direction acting on the cutting blade is measured while the cutting blade is moved in the X direction relative to the sample in the first and second X-direction cutting steps, so the load in the X direction at different depths (positions in the Z direction) in the sample can be determined with high accuracy. Therefore, the measured value of the load in the X direction can be used to analyze the internal state of the sample three-dimensionally with high accuracy. [Effects of the Invention]

[0020] According to the present invention, it is possible to provide a sample analysis method and a sample analysis device that can analyze the internal state of a sample with high precision. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a cross-sectional view of a sample analyzer according to an embodiment. [Figure 2] 1 is a perspective view of a portion of a sample analyzer according to an embodiment. [Figure 3] 10A and 10B are diagrams illustrating the movement direction of a cutting blade in a sample analysis method according to an embodiment. [Figure 4] 1A to 1C are diagrams illustrating an example of a sample analysis method according to an embodiment. [Figure 5] 5 is a diagram showing cutting ranges in the X and Y directions in the sample analysis method shown in FIG. 4. FIG. [Figure 6] FIG. 5 is a diagram showing the load in the X direction (horizontal load) measured in the sample analysis method shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0022] (Embodiment) A sample analysis method according to an embodiment and a sample analysis device capable of carrying out the sample analysis method will be described below with reference to the drawings.

[0023] <Sample analysis equipment> FIG. 1 is a cross-sectional view of the sample analyzer of this embodiment, and FIG. 2 is a perspective view of a portion of the sample analyzer of this embodiment.

[0024] As shown in Figures 1 and 2, the sample analysis device 1 of this embodiment includes a cutting blade 2, a sample stage 4 for fixing a sample 3, driving means 12, 18, and 31 for moving the cutting blade 2 and the sample stage 4 relative to each other, and a control unit 40 for controlling the driving of the driving means 12, 18, and 31.

[0025] The cutting blade 2 and the sample stage 4 are movable relative to each other in the X and Y directions, which are parallel to the surface of the sample 3 and perpendicular to each other, and in the Z direction, which is perpendicular to the surface of the sample 3. FIG. 3 is a diagram illustrating the relative movement direction of the cutting blade 2 with respect to the sample stage 4. In this embodiment, the cutting blade 2 is movable relative to the sample stage 4 along the three axial directions shown in FIG. 3, that is, along the X direction, which is the cutting direction of the cutting blade 2, the Y direction (width direction of the cutting blade 2) perpendicular to the X direction, and the Z direction, which is perpendicular to the surface of the sample 3. Note that the forward and backward directions in the X direction are referred to as the "+X direction" and the "-X direction," respectively, and the downward and upward directions in the Z direction are referred to as the "+Z direction" and the "-Z direction," respectively.

[0026] The cutting blade 2 is supported by a cutting blade support portion 11 held by a main body portion 10. The cutting blade 2 can be moved in the X direction (the direction of the cutting line) together with the main body portion 10 and the cutting blade support portion 11 by a drive means (X-direction movement motor) 12 provided on the opposite side of the main body portion 10 from the cutting blade 2. The X-direction movement motor 12 is provided on a main body support portion 30 via a support base 14. The main body portion 10 is provided on an X-direction guide shaft 17 on the main body support portion 30, sandwiching an X-direction sliding member 16 therebetween, so that the main body portion 10 can move in the X direction on the main body support portion 30. The X-direction movement motor 12 moves the main body portion 10 in the X direction together with the X-direction sliding member 16 via an X-direction threaded rod 13. An X-direction displacement meter 15 is provided on the X-direction guide shaft 17 to measure the X-direction displacement (X-direction movement distance) of the cutting blade 2. As the X-direction displacement meter 15, for example, a laser displacement meter, a micrometer, or the like is used.

[0027] The cutting blade 2 can be moved in the Z direction (a direction perpendicular to the surface of the sample 3) together with the cutting blade support part 11 by a driving means (Z-direction movement motor) 18 provided above the cutting blade support part 11. The Z-direction movement motor 18 is supported by the main body part 10 via a connecting part 19. The Z-direction movement motor 18 moves a nut 21 provided on the side of the main body part 10 in the Z direction via a Z-direction threaded rod 20, and the nut 21 moves the cutting blade 2 in the Z direction together with the cutting blade support part 11. The main body part 10 is provided with a Z-direction displacement meter 22 for measuring the Z-direction displacement of the nut 21, i.e., the Z-direction displacement (Z-direction movement distance) of the cutting blade 2. For example, a contact-type displacement meter such as a scale type, a micrometer, or the like is used as the Z-direction displacement meter 22. The nut 21 is provided on a Z-direction guide shaft 23 on the side of the main body part 10, sandwiching a Z-direction sliding member 24 between them, so that the nut 21 can move in the Z direction on the side of the main body part 10. The cutting blade support part 11 is provided with a Z-direction pressure detector 25 for measuring the pressure (Z-direction pressure) applied from the cutting blade 2 to the sample 3 in the Z direction.

[0028] The sample stage 4 is mounted on the main body support 30, sandwiching, from top to bottom, an X-direction pressure detection sliding member 26, an X-direction pressure detection guide shaft 35, an X-direction tilt adjustment means 36, a Y-direction tilt adjustment means 37, an XY-direction position adjustment member 38, a Y-direction sliding member 27, and a Y-direction guide shaft 28. The X-direction pressure detection sliding member 26 transmits the load applied from the cutting blade 2 during cutting to the X-direction pressure detector 29, and slides along the X-direction pressure detection guide shaft 35 in response to the load applied from the cutting blade 2. The X-direction tilt adjustment means 36 is a member that rotates the sample fixing surface of the sample stage 4 in the X direction (the rotation axis is along the Y direction); specifically, a micrometer can be used. The Y-direction tilt adjustment means 37 is a member that rotates the sample fixing surface of the sample stage 4 in the Y direction (the rotation axis is along the X direction); specifically, a micrometer can be used. The XY-direction position adjustment member 38 is a member for manually moving the sample stage 4 to set it to the cutting start position before the start of automatic cutting. The sample stage 4 is mounted on the Y-direction guide shaft 28 on the main body support part 30, sandwiching the Y-direction sliding member 27, so that it can move in the Y direction on the main body support part 30 together with the X-direction pressure detection sliding member 26, the X-direction pressure detection guide shaft 35, the X-direction tilt adjustment means 36, the Y-direction tilt adjustment means 37, and the XY-direction position adjustment member 38. The X-direction pressure detection guide shaft 35 is provided with an X-direction pressure detector 29 for measuring the pressure applied in the X direction (X-direction pressure) from the cutting blade 2 to the sample 3.

[0029] The sample stage 4 can be moved in the Y direction by a driving means (Y-direction movement motor) 31 arranged on one side of the Y-direction of the Y-direction sliding member 27. The Y-direction movement motor 31 moves the sample stage 4 in the Y direction together with the Y-direction sliding member 27 via a Y-direction threaded rod 32.

[0030] In the sample analyzer 1 of this embodiment, the drive of the X-direction movement motor 12, Z-direction movement motor 18, and Y-direction movement motor 31 is automatically controlled by a control unit 40 equipped with a computer such as a personal computer. The control unit 40 reads information detected by the X-direction displacement meter 15, X-direction pressure detector 29, Z-direction displacement meter 22, and Z-direction pressure detector 25 through an input interface 41, and based on this information, controls the drive of the X-direction movement motor 12 and Z-direction movement motor 18 through a first output interface 42 and controls the drive of the Y-direction movement motor 31 through a second output interface 43.

[0031] The control unit 40 may use the travel distance of the drive command to the Y-direction movement motor 31 for the Y-direction displacement (Y-direction movement distance) of the cutting blade 2, or may use information detected by a separate Y-direction displacement meter for measuring the Y-direction movement distance. Furthermore, the control unit 40 may use the travel distance of the drive command to the X-direction movement motor 12 instead of information detected by the X-direction displacement meter 15 for the X-direction displacement (X-direction movement distance) of the cutting blade 2, or may use the travel distance of the drive command to the Z-direction movement motor 18 instead of information detected by the Z-direction displacement meter 22 for the Z-direction displacement (Z-direction movement distance) of the cutting blade 2. However, during cutting of the sample 3, the travel distance may vary due to a reaction force that the cutting blade 2 receives from the sample 3, etc. Therefore, in order to cut the sample 3 accurately, it is better to perform cutting while precisely monitoring the actual travel distances in the X-direction and Z-direction using a displacement meter.

[0032] In the control unit 40, each function is implemented by the computer executing a program. The computer has, as its main hardware components, a processor that operates according to the program and a memory that stores data necessary for executing the program. The processor may be of any type as long as it can realize the function by executing the program, and may be composed of one or more electronic circuits including, for example, a semiconductor integrated circuit (IC) or an LSI (large scale integration). The program and data are recorded on a non-transitory recording medium such as a computer-readable ROM, optical disk, or hard disk drive. The program and data may be stored in the recording medium in advance, or may be supplied to the recording medium via a wide area communication network including the Internet.

[0033] The control unit 40 is programmed with a first command, a second command, a third command, and a fourth command. The first command causes a first Z-direction cutting step to be performed in which the cutting blade 2 is moved downward in the Z direction or downward in the Z direction and forward in the X direction relative to the sample stage 4 to cut the surface of the sample 3. The second command causes a first X-direction cutting step to be performed following the first Z-direction cutting step in which the cutting blade 2 is moved forward in the X direction relative to the sample stage 4 to cut the sample 3 while measuring the load in the X direction applied to the cutting blade 2. The third command causes a second Z-direction cutting step to be performed at least once after the first X-direction cutting step in which the cutting blade 2 is moved downward in the Z direction or downward in the Z direction and forward in the X direction relative to the sample stage 4 to cut the sample 3. The fourth command causes a second X-direction cutting step to be performed at least once following the second Z-direction cutting step, in which the cutting blade 2 is moved forward in the X-direction relative to the sample stage 4 to cut the sample 3 while measuring the load in the X-direction acting on the cutting blade 2.

[0034] The third command includes a command to cut the sample 3 to a position in the Z direction lower than the cutting position of the first X-direction cutting process in the first second Z-direction cutting process, and to cut the sample 3 to a position in the Z direction lower than the cutting position of the second X-direction cutting process that was performed immediately before in the second or subsequent second Z-direction cutting processes.

[0035] The sample analyzer 1 of this embodiment analyzes the internal state of the sample 3. Specifically, in the sample analyzer 1 shown in Figures 1 and 2, the control unit 40 includes an analysis unit that analyzes the internal state of the sample 3 based on the X-direction loads measured in the first and second X-direction cutting steps. However, this is not limited to this, and the analysis unit may be provided separately from the control unit 40. For example, the analysis unit may be configured as another computer connected to the control unit 40 via a network. The sample analyzer 1 excluding the analysis unit is a cutting device that cuts the sample 3.

[0036] 1 and 2, the driving means for relatively moving the cutting blade 2 and the sample stage 4 include an X-direction movement motor 12 that moves the cutting blade 2 in the X direction, a Z-direction movement motor 18 that moves the cutting blade 2 in the Z direction, and a Y-direction movement motor 31 that moves the sample stage 4 in the Y direction. However, as long as the cutting blade 2 and the sample stage 4 are relatively movable in at least the three axial directions of the X, Y, and Z directions, either the cutting blade 2 or the sample stage 4 may move.

[0037] <Sample analysis method> The sample analysis method of this embodiment using the sample analyzer 1 shown in FIGS. 1 and 2 will now be described.

[0038] In the sample analysis method of this embodiment, first, step (A) is performed to fix the sample 3 on the sample stage 4. For example, the sample stage 4 may be a box-shaped body having a sample suction section (suction hole) on the upper surface on which the sample 3 is placed, and a suction tube (not shown) may be connected to the side of the box-shaped body, and the suction tube may be connected to a vacuum pump (not shown). By operating the vacuum pump, the sample 3 can be sucked downward on the sample stage 4, thereby fixing the sample 3 to the sample stage 4. Instead of such a fixing method, the sample 3 may be fixed to the sample stage 4 by a chemical fixing method using adhesive, hot melt, or the like, or a physical fixing method using bolts, or the like. However, in terms of fixing accuracy and ease of operation, the above-mentioned suction fixation is preferred.

[0039] Next, step (B) is performed to measure the surface inclination of sample 3. Step (B) can be performed using, for example, an indenter that is brought into contact with the surface of sample 3, and the Z-direction displacement meter 22 and Z-direction pressure detector 25 of the sample analyzer 1 as inclination measurement means. Specifically, an indenter is attached to the cutting blade support 11 in place of the cutting blade 2, and while the indenter is in contact with sample 3, the indenter is moved while applying a constant load using the Z-direction pressure detector 25, and the displacement of the indenter is continuously detected using the Z-direction displacement meter 22. This allows information on the surface height of sample 3 to be acquired, thereby measuring the surface inclination of sample 3. Alternatively, the indenter may be pressed against the surface of sample 3 to a constant height position at multiple points on the surface of sample 3 using the Z-direction displacement meter 22, and the load received by the indenter at this time may be detected by the Z-direction pressure detector 25. This allows the load received at a constant height position to be compared at multiple points, thereby measuring the surface inclination of sample 3.

[0040] In addition, when measuring the tilt, it is preferable to move the indenter in at least two directions, the X direction and the Y direction, and in order to further improve the tilt measurement accuracy, it is more preferable to move the indenter in three directions, the X direction, the Y direction, and an oblique direction (for example, a direction intersecting the X direction at 45°), and the tip of the indenter used in the tilt measurement preferably has a curved surface so as not to damage the sample 3 when it comes into contact with the sample 3, and in order to further improve the tilt measurement accuracy, it is more preferable that the tip of the indenter has a spherical shape.

[0041] Next, step (C) is performed to adjust the tilt of the surface of sample 3. For example, the angle of sample 3 can be adjusted using a micrometer (i.e., X-direction tilt adjustment means 36) that rotates the sample fixing surface of sample stage 4 in the X direction (with the rotation axis along the Y direction) and a micrometer (i.e., Y-direction tilt adjustment means 37) that rotates the sample fixing surface of sample stage 4 in the Y direction (with the rotation axis along the X direction). Alternatively, a tilt adjustment means such as an actuator may be used instead of a micrometer. After performing step (C), the tilt measurement of step (B) may be performed again to confirm that the surface of sample 3 has become closer to horizontal.

[0042] After the above steps (A), (B), and (C) are performed, the cutting operation (first Z-direction cutting step, first X-direction cutting step, second Z-direction cutting step, and second X-direction cutting step) is started by the cutting blade 2 of the sample analyzer 1 (cutting device). When starting the cutting operation, the operator may set various cutting conditions, such as the number of cuts, in advance in the control unit 40 so that the cutting operation is performed automatically.

[0043] As cutting conditions, the range of the three-dimensional region to be analyzed in the sample 3 may be set to, for example, 5 μm to 1000 μm in the Z direction and 500 μm to 20000 μm in the X direction. In the Y direction, it may be set to 0.05 mm to 4.0 mm depending on the width of the cutting edge 2.

[0044] Conditions for the first and second Z-direction cutting steps may be, for example, a +Z-direction cutting distance of 1 μm to 100 μm and a +Z-direction cutting speed of 0.1 μm / s to 50 μm / s. The +Z-direction cutting distance is the difference between the measurement depth of the first X-direction load and the measurement depth of the second X-direction load. Therefore, reducing the +Z-direction cutting distance increases the analysis accuracy, while increasing the +Z-direction cutting distance shortens the measurement time. Therefore, the +Z-direction cutting distance may be set by taking these two factors into consideration. The +Z-direction cutting distance may be different for each Z-direction cutting step. For example, cutting may be performed initially with a large +Z-direction cutting distance, and then the +Z-direction cutting distance may be decreased to analyze a specific Z-direction range in detail. Furthermore, when cutting in both the +Z and +X directions in the first and second Z-direction cutting steps, the +X-direction cutting distance may be set to, for example, 500 μm to 20,000 μm and the +X-direction cutting speed to 1 μm / s to 1,000 μm / s.

[0045] As conditions for the first and second X-direction cutting steps, for example, the +X-direction cutting distance may be set to 500 μm to 20,000 μm and the +X-direction cutting speed may be set to 1 μm / s to 1,000 μm / s. Here, the X-direction setting of the above-mentioned "range of the three-dimensional region to be analyzed in sample 3" is performed according to the setting of the +X-direction cutting distance in the first and second X-direction cutting steps.

[0046] The load cell used to measure the X-direction load applied to the cutting edge 2 in the first and second X-direction cutting steps may be selected according to the load to be measured (horizontal load Fh). For example, if the horizontal load Fh is 0.1 N or less, a load cell with a rated capacity of 5 N may be selected; if the horizontal load Fh is more than 0.1 N but less than 20 N, a load cell with a rated capacity of 20 N may be selected; and if the horizontal load Fh is 20 N or more, a load cell with a rated capacity of 100 N may be selected. Since the smaller the rated capacity of a load cell, the better the resolution, so a load cell with a rated capacity of 20 N may be selected for normal sample analysis, a load cell with a rated capacity of 5 N may be selected for analysis of lithium-ion battery electrodes, and a load cell with a rated capacity of 100 N may be selected for analysis of metals.

[0047] [First Z-direction cutting process] In the first Z-direction cutting process, the control unit 40 drives the X-direction movement motor 12 and the Z-direction movement motor 18 to move the cutting blade 2 in the +Z direction (downward in the Z direction) or in the +Z direction and the +X direction (forward in the X direction), thereby starting cutting from the surface of the sample 3.

[0048] Specifically, when the specimen stage 4, to which the specimen 3 is fixed, is set to the cutting start position, the cutting blade 2 and the specimen 3 are spaced apart in the Z direction. Therefore, the control unit 40 first drives the Z-direction movement motor 18 to move the cutting blade 2 downward in the Z direction, bringing the cutting blade 2 into contact with the cutting start position on the surface of the specimen 3. This contact operation may be performed manually, for example, by providing a mechanism for arbitrarily moving the cutting blade 2 in the Z direction. Furthermore, the contact between the specimen 3 and the cutting blade 2 may be confirmed, for example, by using a Z-direction pressure detector 25 to confirm the contact between the specimen 3 and the cutting blade 2. Alternatively, the specimen 3 and the cutting blade 2 may be photographed with a video camera or the like and enlarged and displayed on a personal computer or the like, allowing the operator to visually check the distance between the specimen 3 and the cutting blade 2.

[0049] Next, the control unit 40 drives the X-direction movement motor 12 and the Z-direction movement motor 18 to move the cutting blade 2 in the +Z direction (or in the +Z direction and the +X direction) until the cutting blade 2 reaches the set position (+Z-direction cutting distance and +X-direction cutting distance). At this time, the X-direction pressure detector 29 and the Z-direction pressure detector 25 may be used to detect the X-direction pressure and the Z-direction pressure of the cutting blade 2. This allows the cutting status to be monitored, making it possible to determine whether variations in the cutting operation from the set value have occurred due to effects such as the hardness of the sample 3. If significant variations occur, the cutting operation may be interrupted and steps (B) and (C) may be performed again.

[0050] [First X-direction cutting process] Following the first Z-direction cutting step, in the first X-direction cutting step, the control unit 40 drives only the X-direction movement motor 12 to move the cutting blade 2 in the +X direction until it reaches a set position (+X-direction cutting distance), thereby measuring the X-direction load on the cutting blade 2 while cutting the sample 3. The X-direction load measurement may be performed using the X-direction pressure detector 29. At this time, the cutting operation is performed without displacing the cutting blade 2 in the Z direction, but it is acceptable for the cutting direction to be inclined in the Z direction relative to the X direction within ±2°, preferably ±1°, due to factors such as the inclination of the surface of the sample 3 and the movement accuracy of the cutting blade 2. Note that in the first X-direction cutting step, it is not necessary to cut to the end of the sample 3 in the +X direction.

[0051] In this embodiment, after the first X-direction cutting step, the control unit 40 may drive the Z-direction movement motor 18 to move the cutting blade 2 in the -Z direction (upward in the Z direction). In this way, when the first X-direction cutting step is completed and the cutting blade 2 is moved in the -X direction (backward in the X direction) to the start position of the second Z-direction cutting step described later, the cutting blade 2 can be prevented from contacting the cut surface of the sample 3 formed in the first X-direction cutting step. At this time, the control unit 40 may drive the X-direction movement motor 12 together with the Z-direction movement motor 18 to move the cutting blade 2 in the -Z direction and the +X direction, thereby cutting off a slice from the sample 3.

[0052] Next, the control unit 40 drives the X-direction movement motor 12 to move the cutting blade 2 in the -X direction until it returns to the start position of the second Z-direction cutting step. Here, to shorten the cutting time, the movement speed of the cutting blade 2 in the -X direction (return speed) may be made faster than the movement speed of the cutting blade 2 in the first X-direction cutting step (+X-direction cutting speed). Furthermore, when returning the cutting blade 2 to the start position of the second Z-direction cutting step, the return movement speed may be made slower just before the start position, i.e., just before the stop position of the cutting blade 2. This prevents the cutting blade 2 from shifting position when it is suddenly stopped after moving at high speed in the -X direction.

[0053] [Second Z-direction cutting process] In the second Z-direction cutting step, the control unit 40 drives the X-direction movement motor 12 and the Z-direction movement motor 18 to move the cutting blade 2 in the +Z direction or in both the +Z and +X directions until the cutting blade 2 reaches the set position (+Z-direction cutting distance and +X-direction cutting distance), thereby cutting the sample 3. At this time, the X-direction pressure detector 29 and the Z-direction pressure detector 25 may be used to detect the X-direction pressure and the Z-direction pressure of the cutting blade 2. This allows the cutting status to be monitored, making it possible to determine whether variations in the cutting operation from the set value occur due to effects such as the hardness of the sample 3. If significant variations occur, the cutting operation may be interrupted and steps (B) and (C) may be performed again.

[0054] If the cutting blade 2 and the specimen 3 are spaced apart in the Z direction at the start of the second Z-direction cutting step, the control unit 40 must drive the Z-direction movement motor 18 to move the cutting blade 2 in the +Z direction and bring the cutting blade 2 into contact with the specimen 3. This contact operation may be performed manually, for example, by providing a mechanism for arbitrarily moving the cutting blade 2 in the Z direction. Furthermore, the contact between the specimen 3 and the cutting blade 2 may be confirmed, for example, by using a Z-direction pressure detector 25 to confirm the contact between the specimen 3 and the cutting blade 2, or by photographing the specimen 3 and the cutting blade 2 with a video camera or the like and enlarging and displaying the image on a personal computer or the like, allowing the operator to visually check the distance between the specimen 3 and the cutting blade 2.

[0055] [Second X-direction cutting process] Following the second Z-direction cutting step, in the second X-direction cutting step, the control unit 40 drives only the X-direction movement motor 12 to move the cutting blade 2 in the +X direction until it reaches a set position (+X-direction cutting distance), thereby measuring the X-direction load on the cutting blade 2 while cutting the sample 3. The X-direction load measurement may be performed using the X-direction pressure detector 29. At this time, the cutting operation is performed without displacing the cutting blade 2 in the Z direction. However, due to factors such as the inclination of the surface of the sample 3 and the movement accuracy of the cutting blade 2, it is acceptable for the cutting direction to be inclined in the Z direction relative to the X direction by ±2°, preferably ±1°. Note that in the second X-direction cutting step, it is not necessary to cut all the way to the end of the sample 3 in the +X direction.

[0056] In this embodiment, after the second X-direction cutting step, the control unit 40 may drive the Z-direction movement motor 18 to move the cutting blade 2 in the -Z direction (upward in the Z direction). This prevents the cutting blade 2 from coming into contact with the cut surface of the sample 3 formed in the second X-direction cutting step when the cutting blade 2 is moved in the -X direction to the start position of the next second Z-direction cutting step after the second X-direction cutting step is completed. At this time, the control unit 40 may drive the X-direction movement motor 12 together with the Z-direction movement motor 18 to move the cutting blade 2 in the -Z direction and the +X direction, thereby cutting off a slice from the sample 3.

[0057] Next, the control unit 40 drives the X-direction movement motor 12 to move the cutting blade 2 in the -X direction until it returns to the start position of the next second Z-direction cutting step. Here, to shorten the cutting time, the -X-direction movement speed (return speed) of the cutting blade 2 may be made larger than the movement speed of the cutting blade 2 in the second X-direction cutting step (+X-direction cutting speed). Furthermore, when returning the cutting blade 2 to the start position of the next second Z-direction cutting step, the return movement speed may be made smaller just before the start position, i.e., just before the stopping position of the cutting blade 2. This prevents the cutting blade 2 from shifting position when it is suddenly stopped after moving at high speed in the -X direction.

[0058] The combined process of the second Z-direction cutting step and the second X-direction cutting step is performed once or twice or more times. The number of times the second Z-direction cutting step and the second X-direction cutting step are performed is determined depending on the type of sample 3, but for example, in the case of a battery electrode, they may be performed two to three times.

[0059] If the second Z-direction cutting step is performed once, the second Z-direction cutting step may start from the cutting surface of the first Z-direction cutting step or the first X-direction cutting step. If the second Z-direction cutting step is performed two or more times, the second Z-direction cutting step performed later may start from the cutting surface of the second Z-direction cutting step or the second X-direction cutting step performed immediately before. In other words, the first second Z-direction cutting step starts from the cutting surface of the first Z-direction cutting step or the first X-direction cutting step, and the second and subsequent second Z-direction cutting steps start from the cutting surface of the second Z-direction cutting step or the second X-direction cutting step performed immediately before. In this way, the cutting distance is shorter than when cutting is started from the sample surface in each second Z-direction cutting step, and the time required for analysis can be significantly reduced. The cutting surface in the first and second Z-direction cutting processes is the cutting surface (inclined surface) formed when the cutting blade 2 is moved in the +Z direction and the +X direction to cut the sample 3 in the first and second Z-direction cutting processes.

[0060] In each of the first X-direction cutting step and the second X-direction cutting step, the cutting ranges in the X and Y directions may include the same region. In this way, the state of a specific three-dimensional region inside the sample 3 can be analyzed with high precision using the load measurement value in the X direction.

[0061] [Analysis process] After the cutting operation (first Z-direction cutting step, first X-direction cutting step, second Z-direction cutting step, and second X-direction cutting step) using the cutting blade 2 of the sample analyzer 1 (cutting device) is completed, an analysis step is performed to analyze the internal state of the sample 3 based on the X-direction load measured in the first and second X-direction cutting steps. By comparing the X-direction load (horizontal load) applied to the cutting blade 2 at different depths (Z-direction positions) in the sample 3, the internal uniformity of the sample 3 can be evaluated. Furthermore, the absolute value of the horizontal load can be used to evaluate the Z-direction layer state of the sample 3, such as adhesion, etc. This allows for the analysis of electrodes of, for example, lithium-ion batteries and all-solid-state batteries, specifically, the active material layer on the electrode. Because the active material of all-solid-state batteries is susceptible to deterioration due to moisture in the air, the load measurement is performed in an inert atmosphere, such as a glove box.

[0062] The analysis step may include a first analysis step of determining an average value of the X-direction loads measured in the same specific section in the X direction in the first and second X-direction cutting steps, and a second analysis step of analyzing the internal state of the sample 3 by comparing the average values ​​of the X-direction loads determined in the first analysis step. The specific section may be set in advance before cutting begins, or may be set as a range in which the fluctuation of the X-direction load (horizontal load) is small after the load measurement is completed. When the specific section is set after the load measurement is completed, the specific section may be determined based on the result of plotting the horizontal load against the measurement time or the travel distance.

[0063] <Analysis example> An example of a sample analysis method using the sample analyzer 1 of this embodiment will now be described with reference to FIGS.

[0064] As shown in Fig. 4, in this example, after the first Z-direction cutting step and the first X-direction cutting step are performed, a combination of the second Z-direction cutting step and the second X-direction cutting step is performed three times. In Fig. 4, "first time" represents the first Z-direction cutting step, "second time" represents the first second Z-direction cutting step, "third time" represents the second second Z-direction cutting step, and "fourth time" represents the third second Z-direction cutting step. In the first and second Z-direction cutting steps, the cutting blade 2 is moved the same distance (cutting depth) in the +Z direction, and in the third second Z-direction cutting step, the cutting blade 2 reaches the final depth of the sample 3. The first second Z-direction cutting process starts from the cutting surface of the first X-direction cutting process, the second second Z-direction cutting process starts from the cutting surface of the first second X-direction cutting process, and the third second Z-direction cutting process starts from the cutting surface of the second second X-direction cutting process.

[0065] As shown in FIGS. 4 and 5, in this example, the cutting ranges in the X direction and the Y direction include the same region (specific region) R in the first and second X direction cutting steps.

[0066] Fig. 6 shows the load in the X direction (horizontal load Fh) measured using the sample analysis method shown in Fig. 4. In Fig. 6, "1st time" represents the change in the horizontal load Fh measured in the first X-direction cutting step versus the measurement time, "2nd time" represents the change in the horizontal load Fh measured in the first second X-direction cutting step versus the measurement time, "3rd time" represents the change in the horizontal load Fh measured in the second second X-direction cutting step versus the measurement time, and "4th time" represents the change in the horizontal load Fh measured in the third second X-direction cutting step versus the measurement time.

[0067] In this example, a specific section R is set based on the results shown in FIG. 6, and the average values ​​of the horizontal loads Fh measured in the specific section R in the first and second X-direction cutting processes are calculated. The average values ​​are compared with each other to analyze the internal state of the sample 3.

[0068] <Features of the embodiment> As described above, according to the sample analysis method of this embodiment, the load in the X direction applied to the cutting blade 2 is measured while cutting is performed by moving the cutting blade 2 in the X direction relative to the sample 3 in the first and second X-direction cutting steps, so that the load in the X direction at different depths (positions in the Z direction) in the sample 3 can be determined with high accuracy. Therefore, the internal state of the sample 3 can be analyzed three-dimensionally with high accuracy using the measured value of the load in the X direction.

[0069] In the sample analysis method of this embodiment, the cutting ranges in the X and Y directions may include the same region in each of the first X-direction cutting step and the second X-direction cutting step. In this way, the state of a specific three-dimensional region inside the sample 3 can be analyzed with high precision using the load measurement value in the X direction.

[0070] In the sample analysis method of this embodiment, if the second Z-direction cutting step is performed once, the second Z-direction cutting step may start from the cutting surface of the first Z-direction cutting step or the first X-direction cutting step, and if the second Z-direction cutting step is performed two or more times, the second Z-direction cutting step performed later may start from the cutting surface of the second Z-direction cutting step or the second X-direction cutting step performed immediately before. In this way, the cutting distance is shorter than when cutting is started from the surface of the sample 3 in each second Z-direction cutting step, and the time required for analysis can be significantly reduced.

[0071] In the sample analysis method of this embodiment, the analysis step may include a first analysis step of determining an average value of X-direction loads measured in the same specific section in the X direction in the first X-direction cutting step and the second X-direction cutting step, and a second analysis step of analyzing the internal state of the sample 3 by comparing the average values ​​of X-direction loads determined in the first analysis step. In this way, the internal state of the sample 3 can be analyzed with higher accuracy using the average values ​​of X-direction loads at different depths (Z-direction positions) in the sample 3.

[0072] In the sample analysis method of this embodiment, the sample 3 may be a battery electrode. In this way, the internal state of the battery electrode can be analyzed three-dimensionally with high precision.

[0073] According to the sample analyzer 1 of this embodiment, the load in the X direction applied to the cutting blade 2 is measured while cutting is performed by moving the cutting blade 2 in the X direction relative to the sample 3 in the first and second X direction cutting steps, so that the load in the X direction at different depths (positions in the Z direction) in the sample 3 can be determined with high accuracy. Therefore, the internal state of the sample 3 can be analyzed three-dimensionally with high accuracy using the measured load value in the X direction.

[0074] (Other embodiments) Although the embodiments have been described above, it will be understood that various modifications in form and details are possible without departing from the spirit and scope of the claims. Furthermore, the above embodiments may be combined or substituted as appropriate as long as the functionality of the subject matter of the present disclosure is not impaired. Furthermore, the terms "first," "second," etc., described above, are used to distinguish between terms to which these terms are attached, and do not limit the number or order of the terms. [Explanation of symbols]

[0075] 1. Sample analyzer 2 cutting edges 3. Sample 4 Sample stage 10 Main body 11 Cutting blade support part 12 Drive means (X-direction movement motor) 13 X-direction threaded rod 14 Support stand 15 X-direction displacement sensor 16 X-direction sliding member 17 X-direction guide axis 18 Drive means (Z direction movement motor) 19 Connecting part 20 Z-direction threaded rod 21 Nut 22 Z-direction displacement sensor 23 Z-direction guide axis 24 Z-direction sliding member 25 Z-direction pressure detector 26 X-direction pressure detection sliding member 27 Y-direction sliding member 28 Y-direction guide shaft 29 X-direction pressure detector 30 Main body support part 31 Driving means (Y-direction movement motor) 32 Y-direction threaded rod 35 X-direction pressure detection guide shaft 36 X-direction tilt adjustment means 37 Y direction tilt adjustment means 38 XY direction position adjustment member 40 Control Unit 41 Input Interface 42 First output interface 43 Second output interface

Claims

1. A sample analysis method for analyzing the internal state of a sample using a cutting device, comprising: The cutting device is Cutting edge and a sample stage for fixing the sample; a drive unit that moves the cutting blade and the sample stage relatively; Equipped with the cutting blade and the sample stage are relatively movable in an X direction and a Y direction parallel to a surface of the sample and perpendicular to each other, and in a Z direction perpendicular to the surface of the sample; The sample analysis method includes: a first Z-direction cutting step of cutting from the surface of the sample by moving the cutting blade relative to the sample stage downward in the Z direction or downward in the Z direction and forward in the X direction; a first X-direction cutting step of measuring a load applied to the cutting blade in the X direction while cutting the sample by moving the cutting blade relatively forward in the X direction with respect to the sample stage following the first Z-direction cutting step; a second Z-direction cutting step of cutting the sample by moving the cutting blade downward in the Z direction or downward in the Z direction and forward in the X direction relative to the sample stage after the first X-direction cutting step; a second X-direction cutting step of measuring a load in the X-direction acting on the cutting blade while cutting the sample by moving the cutting blade relatively forward in the X-direction with respect to the sample stage following the second Z-direction cutting step; Including, The second Z-direction cutting step and the second X-direction cutting step are each performed at least once; the first second Z-direction cutting step cuts the sample to a position in the Z direction lower than the cutting position in the first X-direction cutting step; In the second or subsequent Z-direction cutting step, the sample is cut to a position in the Z direction lower than the cutting position in the second X-direction cutting step performed immediately before, The sample analysis method further includes an analysis step of analyzing an internal state of the sample based on the loads in the X direction measured in the first X direction cutting step and the second X direction cutting step. Sample analysis methods.

2. In each of the first X-direction cutting step and the second X-direction cutting step, the cutting ranges in the X direction and the Y direction include the same region. The sample analysis method according to claim 1 .

3. When the second Z-direction cutting step is performed once, the second Z-direction cutting step starts from the cutting surface of the first Z-direction cutting step or the first X-direction cutting step; When the second Z-direction cutting step is performed two or more times, the second Z-direction cutting step performed later starts from the cutting surface of the second Z-direction cutting step or the second X-direction cutting step performed immediately before. The sample analysis method according to claim 1 or 2.

4. The analyzing step a first analysis step of calculating an average value of the loads in the X direction measured in the same specific section in the X direction in the first X-direction cutting step and the second X-direction cutting step; a second analysis step of analyzing the internal state of the sample by comparing the average values ​​of the load in the X direction obtained in the first analysis step with each other; Including, The sample analysis method according to claim 1 or 2.

5. The sample is a battery electrode. The sample analysis method according to claim 1 or 2.

6. A sample analyzer for analyzing the internal state of a sample, comprising: Cutting edge and a sample stage for fixing the sample; a drive unit that moves the cutting blade and the sample stage relatively; a control unit that controls the driving of the driving means; an analysis unit that analyzes the internal state of the sample; Equipped with the cutting blade and the sample stage are relatively movable in an X direction and a Y direction parallel to a surface of the sample and perpendicular to each other, and in a Z direction perpendicular to the surface of the sample; The control unit a first command to perform a first Z-direction cutting step of cutting from the surface of the sample by moving the cutting blade downward in the Z direction or downward in the Z direction and forward in the X direction relative to the sample stage; a second command to execute a first X-direction cutting step in which, following the first Z-direction cutting step, the cutting blade is moved forward in the X-direction relative to the sample stage to cut the sample while measuring the load in the X-direction acting on the cutting blade; a third command to execute a second Z-direction cutting step at least once after the first X-direction cutting step, by moving the cutting blade relative to the sample stage downward in the Z direction, or downward in the Z direction and forward in the X direction, to cut the sample; a fourth command to execute at least once a second X-direction cutting step in which, following the second Z-direction cutting step, the cutting blade is moved forward in the X-direction relative to the sample stage to cut the sample, and the load acting on the cutting blade in the X-direction is measured; is programmed, the third command includes a command to cut the sample in a first second Z-direction cutting step to a position lower in the Z direction than the cutting position in the first X-direction cutting step, and to cut the sample in a second or subsequent second Z-direction cutting step to a position lower in the Z direction than the cutting position in the second X-direction cutting step that was performed immediately before, the analysis unit analyzes an internal state of the sample based on the loads in the X direction measured in the first X direction cutting step and the second X direction cutting step. Sample analysis equipment.

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