X-ray measurement device

Abstract

To align positions while suppressing an increase in mechanism complexity.SOLUTION: Provided is an X-ray measurement device 1 for performing X-ray measurement on a prescribed position of a sample 2 the surface of which is curved. The X-ray measurement device comprises: an acquisition unit for acquiring a diffraction ring when the surface of the sample 2 is irradiated with an X-ray; a calculation unit for, based on the diffraction ring, calculating the incidence angle of the X-ray on the surface of the sample 2 irradiated with the X-ray; and a position correction unit for, based on the incidence angle, calculating a correction value for correcting the irradiation position of X-ray measurement in order for a prescribed position on the surface of the sample to be irradiated with the X-ray.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an X-ray measurement device. [Background technology]

[0002] In order to analyze a sample, there is a method in which X-rays are irradiated toward the sample and the diffraction rings of the X-rays diffracted by the sample are detected. The sample can be analyzed based on the detected diffraction rings. For example, when measuring stress, the surface shape of the sample affects the measurement accuracy. The surface shape may be detected using a line sensor such as that described in Patent Document 1 or a jig that is brought into contact with the sample. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2006-317465 A Summary of the Invention [Problem to be solved by the invention]

[0004] In X-ray measurement equipment, alignment may be required for the apex of a sample surface for X-ray measurements such as stress measurement. In such cases, if a line sensor or a jig is used to detect the apex of the sample surface, the mechanism may become complicated. In addition, a line sensor is likely to be costly, and a contact-type jig may damage the sample surface.

[0005] In view of the above problems, an object of the present invention is to provide an X-ray measuring device that is capable of performing alignment while suppressing the complexity of the mechanism. [Means for solving the problem]

[0006] In order to solve the above problems, the X-ray measurement device of the present invention is an X-ray measurement device that performs X-ray measurement at a predetermined position on a sample having a curved surface, and includes an acquisition unit that acquires a diffraction ring when X-rays are irradiated onto the surface of the sample, a calculation unit that calculates, based on the diffraction ring, the angle of incidence of the X-rays on the surface of the sample irradiated with the X-rays, and a position correction unit that calculates, based on the angle of incidence, a correction value for correcting the irradiation position of the X-ray measurement so as to irradiate the X-rays to the predetermined position on the surface of the sample.

[0007] In the X-ray measurement device, the calculation unit calculates the angle of incidence based on Fourier coefficients obtained by expanding a distribution of a parameter related to intensity at a plurality of α angles in the diffraction ring into a Fourier series.

[0008] In the X-ray measurement device, the Fourier coefficients are coefficients of a first-order cosine wave in the Fourier series expansion.

[0009] In the X-ray measurement apparatus, the calculation unit calculates the angle of incidence from the Fourier coefficients based on correction information in which the angle of incidence is associated with a quadratic expression of the Fourier coefficients.

[0010] In addition, in the X-ray measurement device, the correction information is set based on a plurality of reference diffraction rings obtained by changing the incidence angle of the X-rays and the distance from the irradiation position of the X-rays to the reference sample, the reference sample having a flat surface.

[0011] In addition, in the X-ray measurement device, the predetermined position on the surface of the sample is a vertex on the surface of the sample. Effect of the Invention

[0012] According to the X-ray measuring device of the present invention, alignment can be performed while suppressing the complexity of the mechanism. [Brief description of the drawings]

[0013] [Figure 1]1 is a diagram showing an example of the configuration of an X-ray measurement apparatus according to an embodiment of the present invention. [Diagram 2] 2 is a block diagram showing an example of various functions in a processing unit in FIG. 1. [Diagram 3] 2 is a diagram showing an example of a diffraction ring detected by a detection unit in FIG. 1. [Figure 4] 2 is a diagram showing an example of a case where a sample is irradiated with X-rays by the X-ray measuring device of FIG. 1. [Diagram 5] FIG. 13 is a diagram illustrating an example of the relationship between integrated intensity and distance. [Figure 6] FIG. 13 is a diagram showing an example of the relationship between integrated intensity and α angle. [Figure 7] FIG. 13 is a diagram illustrating an example of a relationship between an incident angle and a Fourier coefficient. [Figure 8] 2 is a flowchart showing an example of the flow of a position correction process by the processing unit in FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. In order to facilitate understanding of the description, the same reference numerals are used to designate the same components in each drawing, and duplicated description will be omitted as appropriate.

[0015] === Implementation form === <Overall composition> FIG. 1 is a diagram showing an example of the configuration of an X-ray measurement device 1 according to this embodiment. The X-ray measurement device 1 irradiates a sample 2 with X-rays, detects X-rays diffracted by the sample 2, and performs X-ray measurement. The sample 2 is an object to be analyzed, and is, for example, an automobile part such as a gear, a crankshaft, a shaft, or other parts. The sample 2 is, for example, a steel material. In particular, the surface of the sample 2 is curved and has a vertex on the surface. The vertex is the vertex of a convex part on the surface. Note that, in this embodiment, a case where X-rays are irradiated with the vertex of the sample 2 as a target irradiation position for X-ray measurement will be described as an example, but the target irradiation position of the X-rays is not limited to the vertex, and may be a predetermined position on the surface of the sample 2. The parameter of the sample 2 to be analyzed is, for example, the stress of the sample 2.

[0016] 1, the X-ray measurement device 1 has a main body 10, and its main components are a tube 11, a collimator 12, a substrate 13, and a detection unit 14. The X-ray measurement device 1 also has a processing unit 15.

[0017] The tube 11 functions as an irradiation unit that generates X-rays and irradiates the generated X-rays toward the sample 2. The tube 11 is made of a material such as glass or metal.

[0018] Collimator 12 has a function of adjusting the irradiation range of the X-rays generated by tube 11. Collimator 12 is provided below (on the substrate side) of tube 11, and extends toward substrate 13. The X-rays generated by tube 11 pass through collimator 12 and are irradiated onto sample 2.

[0019] The substrate 13 is a plate-like member, and is provided with a detection unit 14, which will be described later. A hole is provided in the substrate 13, and a collimator 12 extending from the bulb 11 side protrudes from this hole to the sample 2 side.

[0020] The detector 14 has, for example, a rectangular shape, and is provided on the substrate 13 on the side of the sample 2 (the side opposite to the tube 11). The detector 14 detects X-rays diffracted from the sample 2. Specifically, the detector 14 detects a diffraction ring, which is a ring-shaped diffraction image of the diffracted X-rays. The diffraction ring is also called a Debye ring or a Debye-Scherrer ring. The detector 14 is an imaging element for imaging the diffraction ring, and is, for example, an SOI (Silicon on Insulator) sensor. For example, the detector 14 is composed of two chips provided on either side of the collimator 12. The number of chips is not limited.

[0021] The processing unit 15 is an information processing device that calculates a correction value (amount of deviation) for aligning the irradiation of X-rays based on the detection result of the detection unit 14. The processing unit 15 includes, for example, a control device 20, a communication device 21, and a storage device 22. The control device 20 is mainly configured with a CPU (Central Processing Unit) 25 and a memory 26. In the control device 20, the CPU 25 executes a predetermined program stored in the memory 26 or the storage device 22, etc., thereby functioning as various functional configurations described below. The communication device 21 includes a communication interface for communicating with an external device, etc. The storage device 22 includes a hard disk, etc., and stores various programs and various information required for executing the processing in the control device 20, as well as information on the processing results. The processing unit 15 may be configured with a single information processing device or may be configured with multiple information processing devices. Also, FIG. 1 shows only a part of the main hardware configuration of the processing unit 15, and the processing unit 15 may include other configurations such as an operation device and a display device.

[0022] <Functional configuration> 2 is a block diagram showing an example of various functions in the processing unit 15 of the X-ray measuring device 1. The position correction process is executed by the function in each block.

[0023] As shown in FIG. 2, the processing unit 15 includes an acquisition unit 31, a calculation unit 32, and a position correction unit 33 as main components.

[0024] The acquisition unit 31 acquires the diffraction ring detected when X-rays are irradiated onto the sample 2. Specifically, the acquisition unit 31 acquires the diffraction ring detected by the detection unit .

[0025] FIG. 3 is a diagram showing an example of a diffraction ring detected by the detection unit 14. X-rays irradiated to the sample 2 are detected as a diffraction ring, for example as shown as C in FIG. 3. The angle of the diffraction ring in the circumferential direction is the α angle. Parts of the diffraction ring are detected by each of the two chips constituting the detection unit 14. In other words, the α angle is the central angle of the diffraction ring on the detection plane of the detection unit 14. A part of the diffraction ring may be detected, or the entire circumference (whole) of the diffraction ring may be detected. Returning to FIG. 2, the diffraction ring acquired by the acquisition unit 31 is output to the calculation unit 32.

[0026] The calculation unit 32 calculates the incidence angle φ of the X-rays on the surface of the sample 2 irradiated with the X-rays, based on the diffraction ring. The incidence angle φ is the angle at which the X-rays are incident with respect to the normal to the surface of the sample 2. The calculation unit 32 includes an identification unit 36, a Fourier unit 38, and an incidence angle calculation unit 39.

[0027] The determination unit 36 ​​determines a parameter related to intensity for a plurality of α angles in the diffraction ring. The plurality of α angles are set, for example, at equal intervals in the circumferential direction. In this embodiment, it is assumed that W1 α angles are set. The parameter related to intensity is the integrated intensity. That is, the determination unit 36 ​​determines the integrated intensity for each of the profiles (diffraction profiles) corresponding to the plurality of α angles. The profile indicates the radial intensity distribution of the diffraction ring at a particular α angle. For example, the profile is shown as a distribution of radial positions (e.g., pixels) based on the center of the diffraction ring on the vertical axis and the horizontal axis. For example, in the profile, the intensity is high at radial positions where the diffraction ring is detected, and the intensity is low at positions where the diffraction ring is not detected.

[0028] The integrated intensity is calculated, for example, by fitting the profile with a Gaussian function and calculating the product of the peak value of the Gaussian distribution and the width parameter σ. The integrated intensity may be a value obtained by integrating the entire (or a part) of the profile. The parameter related to the intensity may be the peak intensity (for example, the peak value of the fitted Gaussian distribution). In this way, the determination unit 36 ​​obtains integrated intensities corresponding to each of W1 α angles.

[0029] In addition, the identifying unit 36 ​​determines the distance C between the X-ray measuring device 1 and the sample 2 based on the diffraction ring. L Identify the distance C. L is the distance C between the end (irradiation position) of the collimator 12 that irradiates the X-rays and the surface of the sample 2 L In addition, the distance C L is the distance C between the detection surface of the sensor in the detection unit 14 and the surface of the sample 2 L For example, the specifying unit 36 ​​may be set to a distance C from the average of the peak intensities of the profiles of the multiple α angles. L Based on the diffraction ring, the distance C L There is no limitation on the method for identifying the

[0030] The Fourier unit 38 performs a Fourier series expansion on the distribution of the integrated intensity with respect to the α angle. In this embodiment, the Fourier unit 38 performs a second-order Fourier series expansion. That is, the Fourier unit 38 calculates, as Fourier coefficients, a0 of the 0th order in the Fourier series expansion, a1 of the first-order cosine wave (cosα), a1 of the first-order sine wave (sinα), a2 of the second-order cosine wave (cos2α), and a2 of the second-order sine wave (sin2α). The Fourier unit 38 outputs the calculated Fourier coefficient a1, which is the coefficient of the first-order cosine wave, to the incident angle calculation unit 39. Note that other coefficients of the Fourier series expansion may be used as the Fourier coefficients.

[0031] The incident angle calculation unit 39 calculates the incident angle φ based on the Fourier coefficient a1 calculated by the Fourier series expansion. Specifically, the incident angle calculation unit 39 calculates the incident angle φ from the Fourier coefficient a1 based on the correction information.

[0032] The correction information corresponds to the incident angle φ as a quadratic expression of the Fourier coefficient a1, as shown in the following equation (1).

[0033]

number

[0034] The coefficients D, E, and F in the formula (1) are set in advance. The incident angle calculation unit 39 substitutes the calculated Fourier coefficient a1 into the formula (1) to calculate the incident angle φ. The incident angle φ is output to the position correction unit 33.

[0035] Based on the incident angle φ, the position correction unit 33 calculates a correction value for correcting the irradiation position of the X-ray measurement for irradiating the vertex on the surface of the sample 2 with the X-ray. Specifically, the position correction unit 33 calculates the amount of positional deviation based on the true incident angle φ0, which is the incident angle φ when the X-ray is incident on the vertex, which is the target irradiation position of the X-ray, and the calculated incident angle φ. The true incident angle φ0 is set in advance as the angle at which the X-ray is incident on the vertex. On the other hand, the incident angle φ is the incident angle φ when the X-ray is actually irradiated onto the sample 2.

[0036] FIG. 4 is a diagram showing an example of X-ray irradiation on a sample 2 with a circular surface. In FIG. 4, the sample 2 is shown in cross section, and the surface shape is constant with a curvature r. The horizontal direction is the x-axis, and the vertex position is x=0. For example, when X-rays are irradiated onto a vertex of a surface at x=0, the true incident angle is φ0. In contrast, when X-rays are irradiated onto a surface at x=x1, the incident angle is φ. In other words, when X-rays are irradiated onto a vertex so as to achieve a true incident angle φ0, if the irradiation position is shifted to x=x1, the true incident angle is not φ0 but is instead an incident angle φ. In such a case, the amount of deviation x in the x-axis direction from the vertex x=0 is m (=x1) is expressed by the following equation (2).

[0037]

number

[0038] For this reason, the position correction unit 33 uses the preset curvature r and true incident angle φ0, and the calculated incident angle φ, and calculates the deviation amount x as a correction value according to equation (2). m Calculate the deviation x m By performing the measurement again at the position where the angle has been corrected, the vertex can be irradiated with X-rays at a true incident angle φ0.

[0039] The surface shape of the sample 2 is not limited to the circle shown in FIG. 4, and can correspond to various curved surfaces. For example, if the cross section of the sample 2 is an ellipse with the radius of the major axis being a and the radius of the minor axis being b, the x-axis is taken parallel to the major axis, the y-axis is taken parallel to the minor axis, and the positions of the vertices are x=0 and y=b. In such a case, the amount of deviation x in the x-axis direction is m is expressed by the following formula (3), and the deviation amount x m The position y on the y-axis corresponding to the position n becomes equation (4).

[0040]

number

[0041] The position correction unit 33 uses a, which is a radius of the major axis, b, which is a radius of the minor axis, and a true incident angle φ0, and the incident angle φ calculated by the calculation unit 32, and calculates the deviation amount x as a correction value according to Equation (3). m Calculate the deviation x in both the positive and negative directions along the x-axis as ± using formula (3). m Therefore, in equation (4), the position y n The deviation x is set to be positive. m In this manner, the sign of the deviation x is determined even when the sample 2 has an elliptical shape. m can be calculated.

[0042] <Correction information settings> Next, the setting of the correction information will be described. The correction information is generated using information set in advance for X-ray measurement. A reference sample with a flat surface is used to set the correction information. The incident angle φ and the distance C L The diffraction ring for the reference sample is taken as the reference diffraction ring. For example, the incident angle φ is W2 and the distance C L If the number of reference diffraction rings is W3, then W2 × W3 reference diffraction rings will be obtained.

[0043] Then, based on each reference diffraction ring, the integrated intensity and the distance C are calculated for each of the W1 α angles and the W2 incident angles φ. L Figure 5 shows the relationship between the integral intensity and the distance C for a certain incident angle φ and a certain α angle. L 5 is a graph showing an example of the relationship between the distance C and the integrated intensity. L The values ​​are plotted based on the standard diffraction ring, and the integrated intensity is approximated as I = AC L +B and a linear equation M1, where A is the slope and B is the intercept. Note that other approximation equations, such as a quadratic equation, may also be used. That is, the integral intensity I(φ, α, C L ) is the distance C L This linear equation M1 is set for each of W1 α angles and W2 incidence angles φ. That is, W1×W2 linear equations M1 are set. Coefficients A and B may have different values ​​depending on the incidence angle φ and α angle.

[0044] The determination unit 36 ​​determines the distance C corresponding to the detected diffraction ring. L Target distance C L0 Then, by substituting the above into each of the W1 × W2 linear equations M1, the integral intensity corresponding to each combination of the W1 α angles and the W2 incidence angles φ is calculated as I(φ, α, C L0) is obtained. By summarizing this integrated intensity for each incident angle φ, a distribution of the integrated intensity for the α angle is obtained. FIG. 6 is a diagram showing an example of the distribution of the integrated intensity for the α angle. In FIG. 6, the vertical axis represents the integrated intensity, and the horizontal axis represents the α angle, and the distribution is shown for each incident angle φ. As an example, the incident angle φ is shown as three angles of incidence φ, φ1, φ2, and φ3, and the corresponding distributions are shown as distribution L1, distribution L2, and distribution L3. Then, the Fourier unit 38 expands each distribution into a Fourier series to obtain a result FL1 corresponding to distribution L1, a result FL2 corresponding to distribution L2, and a result FL3 corresponding to distribution L3.

[0045] In this way, the incident angle φ and the corresponding Fourier coefficient a1 are associated with each other. FIG. 7 is a diagram showing an example of the distribution of the incident angle φ with respect to the Fourier coefficient a1. In FIG. 7, the vertical axis represents the incident angle φ, and the horizontal axis represents the Fourier coefficient a1. The incident angle calculation unit 39 obtains the formula (1) by approximating the plotted distribution with a quadratic formula M2. In this way, the correction information is set based on the reference sample.

[0046] <Processing flow> 8 is a flowchart showing an example of the flow of the position correction process according to this embodiment. Each process in the following steps is started after, for example, irradiating the sample 2 to be measured with X-rays. Note that the order and contents of each step in the following steps can be changed as appropriate.

[0047] (Step SP10) The acquisition unit 31 acquires a diffraction ring of the X-rays irradiated onto the sample 2. Then, the process proceeds to step SP11.

[0048] (Step SP11) The determination unit 36 ​​determines the distance C based on the obtained diffraction ring. L Identify the distance C. L Target distance C L0 Then, the process proceeds to step SP12.

[0049] (Step SP12) Target distance C L0Specifically, the determination unit 36 ​​sets the correction information corresponding to I(φ,α,C) as the integrated intensity corresponding to each of W1 α angles and W2 incident angles φ based on the linear equation M1 based on the reference diffraction ring. L0 ) is obtained. The Fourier section 38 performs a Fourier series expansion of the distribution of the integrated intensity with respect to the α angle for each incident angle φ, and associates the incident angle φ with the Fourier coefficient a1. The incident angle calculation section 39 then approximates the relationship between the incident angle φ and the Fourier coefficient a1 to obtain the formula (1) as correction information. That is, the target distance C L0 Then, the process proceeds to step SP13.

[0050] (Step SP13) The identifying unit 36 ​​identifies the integrated intensity in the profile of each of the W1 α angles for the diffraction ring acquired in step SP10, and then proceeds to step SP14.

[0051] (Step SP14) The Fourier section 38 performs a Fourier series expansion on the integrated intensity for each of the W1 α angles. That is, the Fourier series expansion is performed on the distribution of the integrated intensity for the α angle. Then, the process proceeds to step SP15.

[0052] (Step SP15) The Fourier section 38 sets the coefficient of the first-order cosine wave in the Fourier series expansion as the Fourier coefficient a1, and then proceeds to step SP16.

[0053] (Step SP16) The incident angle calculation unit 39 calculates the incident angle φ from the Fourier coefficient a1 based on the correction information, and then proceeds to step SP17.

[0054] (Step SP17) The position correction unit 33 calculates a correction value for the position of the vertex based on the incident angle φ. Specifically, the position correction unit 33 calculates the correction value by calculating the amount of deviation x of the X-ray irradiation position with respect to the position of the vertex. m Calculate.

[0055] In this way, the deviation of the X-ray irradiation position from the vertex position x m is calculated, and the calculated deviation x m By moving the X-ray measuring device 1 based on the correction value, it becomes possible to irradiate the vertex with X-rays at a true incident angle φ0. The X-ray measuring device 1 may be moved by a driving mechanism or the like based on the correction value, or may be moved by an operator or the like. m After moving the sample 2 based on the above, the above flow may be executed again to check the incident angle φ. After the alignment is performed, the apex of the sample 2 is irradiated with X-rays, and the stress can be measured from the obtained diffraction ring, for example.

[0056] <Action and effect> As described above, in this embodiment, the X-ray measurement apparatus 1 is an X-ray measurement apparatus 1 that performs X-ray measurement on a vertex, which is a predetermined position, of a sample 2 having a curved surface, and includes an acquisition unit 31 that acquires a diffraction ring when X-rays are irradiated onto the surface of the sample 2, a calculation unit 32 that calculates, based on the diffraction ring, the incidence angle φ of the X-rays on the surface of the sample 2 irradiated with the X-rays, and a position correction unit 33 that calculates, based on the incidence angle φ, a correction value for correcting the irradiation position of the X-ray measurement to irradiate the X-rays to the vertex on the surface of the sample 2. According to this configuration, a correction value for the irradiation position for irradiating X-rays to the apex, which is a predetermined position, can be obtained from the diffraction ring obtained by irradiating X-rays. By making corrections using this correction value, alignment to the predetermined position can be performed. For example, although the measured stress value may change significantly due to a positional deviation from the apex, alignment to the apex position can be performed, so it is possible to improve the accuracy of X-ray measurement. In addition, for example, a line sensor or a contact-type jig is not required, and the complexity of the configuration is suppressed. It is also possible to miniaturize the device (measurement head), making it possible to apply it to narrow areas.

[0057] Moreover, in the X-ray measurement apparatus 1 according to this embodiment, the calculation unit 32 calculates the incident angle φ based on the Fourier coefficient a1 obtained by expanding the distribution of the parameter related to the intensity at a plurality of α angles in the diffraction ring into a Fourier series. According to this configuration, the angle of incidence φ can be calculated from the diffraction ring by using a Fourier series expansion.

[0058] Moreover, in the X-ray measurement apparatus 1 according to this embodiment, the Fourier coefficient a1 is the coefficient of a first-order cosine wave in the Fourier series expansion. According to this configuration, it is possible to calculate the incident angle φ by using the coefficient of a first-order cosine wave.

[0059] Moreover, in the X-ray measurement apparatus 1 according to this embodiment, the calculation unit 32 calculates the incident angle φ from the Fourier coefficient a1 based on the correction information in which the incident angle φ is associated with the Fourier coefficient a1 by a quadratic expression. According to this configuration, the incidence angle φ and the Fourier coefficient a1 correspond to each other by a quadratic expression, so that the incidence angle φ can be calculated from the Fourier coefficient a1 with high accuracy.

[0060] In the X-ray measurement device 1 according to this embodiment, the correction information is the incidence angle φ of the X-ray with respect to a reference sample having a flat surface, and the distance C from the irradiation position of the X-ray to the reference sample. L The diffraction pattern is set based on a plurality of reference diffraction rings obtained by changing each of the above. According to this configuration, the incidence angle φ and the distance C L By using a reference diffraction ring in which the angle of incidence φ is changed multiple times, it is possible to set correction information in which the angle of incidence φ corresponds to a quadratic expression of the Fourier coefficient a1 with high accuracy.

[0061] In the X-ray measurement apparatus 1 according to this embodiment, the predetermined position on the surface of the sample 2 is the apex of the surface of the sample 2 . According to this configuration, since alignment can be performed with respect to the vertex, for example, it becomes possible to measure stress with high accuracy.

[0062] <Modification> The present invention is not limited to the above-described embodiment. In other words, the above-described specific example may be modified by a person skilled in the art as appropriate, and the modifications may be included in the scope of the present invention as long as they include the features of the present invention. In addition, the elements of the above-described embodiment and the following modifications may be combined to the extent technically possible, and the combinations of these may be included in the scope of the present invention as long as they include the features of the present invention.

[0063] For example, in the above embodiment, a case has been described in which the processing unit 15 is provided separately from the main body unit 10, but the processing unit 15 is not limited to being provided separately from the main body unit 10, and may be mounted on the main body unit 10.

[0064] Furthermore, in the above embodiment, a mathematical formula is used as the correction information, but the correction information is not limited to a mathematical formula and may be in the form of, for example, a graph or a table.

[0065] In the above embodiment, after obtaining the diffraction ring for X-ray measurement, the target distance C L0 We have explained the case where equation (1) is obtained by adjusting the distance C L After obtaining the diffraction ring, the target distance C identified by the identification unit 36 ​​is L0 The distance C corresponding to L It is also possible to read out and use the formula (1) above. L0 The distance C corresponding to L The equation (1) is the distance C L is the target distance C L0 or the target distance C L0 Distance C L may be within an acceptable range. [Explanation of symbols]

[0066] 1:X-ray measuring device 2: Sample 31: Acquisition part 32: Calculation section 33:Position correction section xm : Deviation amount (correction value) φ: Incident angle

Claims

1. 1. An X-ray measurement apparatus for performing X-ray measurement on a predetermined position of a sample having a curved surface, comprising: an acquisition unit that acquires a diffraction ring when an X-ray is irradiated onto a surface of the sample; a calculation unit that calculates an incident angle of the X-ray on the surface of the sample irradiated with the X-ray based on the diffraction ring; a position correction unit that calculates a correction value for correcting an irradiation position of the X-ray measurement for irradiating the X-ray to the predetermined position on the surface of the sample based on the incident angle; An X-ray measuring device comprising:

2. the calculation unit calculates the angle of incidence based on Fourier coefficients obtained by expanding a distribution of a parameter related to intensity at a plurality of α angles in the diffraction ring into a Fourier series.

2. The X-ray measurement device according to claim 1.

3. The Fourier coefficients are the coefficients of a first order cosine wave in the Fourier series expansion.

3. The X-ray measurement device according to claim 2.

4. the calculation unit calculates the angle of incidence from the Fourier coefficients based on correction information in which the angle of incidence is associated with a quadratic expression of the Fourier coefficients; 4. The X-ray measuring device according to claim 2 or 3.

5. the correction information is set based on a plurality of reference diffraction rings obtained by changing the incidence angle of the X-ray and the distance from the irradiation position of the X-ray to the reference sample, the reference sample having a flat surface, in a plurality of times.

5. The X-ray measuring device according to claim 4.

6. the predetermined location on the surface of the sample is a vertex on the surface of the sample; 3. The X-ray measuring device according to claim 1 or 2.

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