JPH10253553A - Method for regulating angle of inclination of crystal of single-crystal sample in measurement of x-ray diffraction - Google Patents

Abstract

PROBLEM TO BE SOLVED: To regulate the angle of inclination of crystal of a single-crystal sample accurately and quickly by changing the angle of inclination of the crystal, fitting respective peak intensities or the like of a plurality of rocking curves measured to a prescribed function curve, and using the angle of inclination of the crystal corresponding to the position of the apex thereof. SOLUTION: Angle α of inclination of a crystal is changed every Δα1 and a rocking curve is measured a plurality of times for each change within an angular range of ±Δω1 with respect to the axis ω, with a scan speed set at v1 per minute. The peak intensity or the like of each rocking curve is plotted for the angle α of inclination of the crystal. The result of plotting is fitted to a function curve having one Gaussian or other peak value and the angle α of inclination of the crystal corresponding to the point of the apex thereof is made α1 . Next, the rocking curve is measured likewise in a plurality of times in the range of ±Δα (Δα-Δα1 /2) in the front and the rear of α1 . The respective peak intensities or the like of the rocking curves are plotted and fitted to the function curve. Regulation is conducted by using the angle α of inclination of the crystal corresponding to the position of the apex thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for adjusting a crystal tilt angle which is performed when an X-ray diffraction measurement is performed on a single crystal sample, and more particularly to a method for adjusting a crystal tilt angle which can be adjusted accurately and quickly.

[0002]

2. Description of the Related Art FIG. 1 is a diagram showing a configuration of an X-ray diffraction apparatus used for general X-ray diffraction measurement. Normally, X-ray diffraction measurement is performed by applying X-ray to the surface of a sample (here, a single crystal sample) 1.
The X-ray generated by the X-ray tube 3 is incident from a certain direction, the intensity of the diffraction line is measured by the counter tube 5, and the intensity is obtained as an angle θ. Using this X-ray diffractometer, the intensity distribution (usually referred to as “rocking curve”) of the diffraction line when the single crystal sample 1 is rotated near an orientation satisfying the Bragg condition is determined, and the structure of the single crystal sample 1 is obtained. An analysis is performed.

When performing such X-ray diffraction measurement, it is very important to minimize the crystal tilt angle in order to obtain reliable data. FIG. 2 shows FIG.
2 is a view of the single crystal sample 1 shown in FIG. As shown in this figure, the surface 7 of the single crystal sample 1 and the lattice plane 9 to be measured do not usually coincide with each other, and the plane perpendicular to the rotation axis (ω axis) of the single crystal sample 1 and the single crystal sample 1 Has a certain angle (hereinafter, referred to as “crystal tilt angle (α)”) with the normal vector of the lattice plane 9. Therefore, the lattice plane 9
In order to analyze accurately, it is necessary to make the crystal tilt angle as small as possible and ultimately to zero.

Conventionally, the following method has been widely known as a method for adjusting the crystal tilt angle.

(1) First Method While changing the crystal tilt angle α little by little, for example, Δα, a rocking curve is measured for each angle. Then, the adjustment is performed using the crystal inclination angle α of the rocking curve having the maximum peak intensity (or the minimum half-value width) among the plurality of measured rocking curves.

(2) Second method A light receiving aperture is placed at an appropriate distance from the sample on the rotation plane of the sample (ω axis), and two half slits (upper half and lower half) are placed at the position of the light receiving aperture. The X-ray intensity is adjusted so that the X-ray intensity of the upper half slit is equal to that of the lower half slit.

(3) Third method The first method described in the above (1) is improved.
While gradually changing the crystal tilt angle α (by Δα),
A rocking curve is measured for each angle. And
The measured peak intensity (or half-width) of the rocking curve is plotted against the crystal inclination angle α, fitted to an appropriate function curve, and adjusted using the crystal inclination angle α corresponding to the vertex position of the curve. .

[0008]

However, the conventional crystal tilt angle adjusting method has the following disadvantages.

In the first method, it is necessary to measure the rocking curve a very large number of times, which takes a lot of time and has a certain limit in the adjustment accuracy (to obtain an accuracy of Δα or less). It is difficult.).

In the second method, it is necessary that the light receiving aperture is correctly positioned on the rotation plane of the ω axis, but it is not easy to determine the correct position (the rotation plane of the ω axis) of the light receiving aperture. In addition, if the position of the light receiving aperture is shifted for some reason, an accurate crystal tilt angle α cannot be formed. Therefore, it is necessary to frequently check the position of the light receiving aperture. Further, the adjustment work for guiding the diffracted X-rays to reach the position of the light-receiving aperture and the work for precisely adjusting them are very complicated.

In the third method, when Δα is made larger, the adjustment accuracy is reduced, and when Δα is made smaller, the adjustment accuracy is usually improved, but the crystal inclination angle at the start of the adjustment is reduced. If α deviates significantly from the true value, it takes a lot of time for the measurement.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an X-ray apparatus capable of accurately and quickly adjusting a crystal tilt angle when measuring an X-ray diffraction of a single crystal sample. An object of the present invention is to provide a method for adjusting a crystal tilt angle of a single crystal sample in diffraction measurement.

[0013]

Means for Solving the Problems To achieve the above object, a first feature of the present invention is that, when measuring X-ray diffraction of a single crystal, it is perpendicular to the rotation axis (ω axis) of the single crystal sample. in the crystal inclination angle adjusting method formed by the normal vector of the plane and a single crystal lattice plane, the crystal tilt angle is changed by [Delta] [alpha] _1, a range of ± [Delta] [omega ₁ per the change, the scanning speed v ₁ for the ω axis Are measured, and one of the peak intensity, half width, peak position or peak angle of each of the plurality of rocking curves is plotted against the crystal tilt angle, and the result is plotted as one peak value. A first function curve fitting to an arbitrary first function curve having the following equation, and setting a crystal inclination angle corresponding to a vertex position of the first function curve to α _1, and the α step obtained in the first step. _In the vicinity of _1, the crystal tilt angle is not Δα ₂ One is varied in the range of ± [Delta] [omega ₂ per the change, the ω plurality measures the rocking curve of the scanning speed v ₂ for the shaft, the rocking curve respective peak intensities of the plurality of half-width, the peak position or peak angle Is plotted against the crystal tilt angle, and the result is fitted to an arbitrary second function curve having one peak value, and the crystal tilt corresponding to the position of the vertex of the second function curve is obtained. A second step of adjusting using an angle, wherein the Δα ₁ , Δα ₂ , Δω ₁ ,
Δω _2, v ₁ and v _{2 is, Δα 1/20 ≦ Δα 2} ≦ Δα
_{1/10, Δω 1/10} ≦ Δω 2 ≦ Δω 1/4, v 1 /
Is to satisfy _{10 ≦ v 2 ≦ v 1/} 3.

A second feature of the present invention is that, in X-ray diffraction measurement of a single crystal, a crystal formed by a plane perpendicular to a rotation axis (ω axis) of a single crystal sample and a normal vector of a single crystal lattice plane. In the tilt angle adjusting method, the crystal tilt angle is changed by Δα _{1 at a} time,
In the range of ± every change [Delta] [omega _1, wherein the ω-axis step size [Delta] [theta] ₁ for a plurality measured rocking curve by performing the steps scanning counting time t _1, the rocking curve respective peak intensities of the plurality of the half-value width , One of the peak positions or peak angles is plotted against the crystal tilt angle, and the result is fitted to an arbitrary first function curve having one peak value, and the peak of the first function curve is plotted. first to the crystal inclination angle corresponding to the position and alpha ₁
And the vicinity of α ₁ obtained in the first step,
It said crystal tilt angle is changed by [Delta] [alpha] _2, in a range of ± [Delta] [omega ₂ per the change, the ω axis step width Δ for
θ ₂ , a plurality of rocking curves are measured by performing step scanning of the counting time t ₂ , and one of the peak intensity, half width, peak position or peak angle of each of the plurality of rocking curves is determined with respect to the crystal tilt angle. A second step of fitting the result to an arbitrary second function curve having one peak value and adjusting using a crystal tilt angle corresponding to the position of the vertex of the second function curve. Wherein Δα ₁ , Δα ₂ , Δω ₁ , Δω ₂ , Δ
θ _1, t _1, is [Delta] [theta] ₂ and _{t 2, Δα 1/20 ≦} Δα 2
_{≦ Δα 1/10, Δω 1} /10 ≦ Δω 2 ≦ Δω 1/4,
_{Δθ 1/5 ≦ Δθ 2 ≦} Δθ 1/2, (Δθ 1 / t 1) /
10 ≦ (Δθ ₂ / t ₂ ) ≦ (Δθ ₁ / t ₁ ) / 3.

According to the above configuration, even if there is a considerable shift in the crystal tilt angle at the start of the adjustment, the crystal tilt angle can be easily and accurately and quickly adjusted without requiring an enormous amount of time and complicated operations. Is possible. Therefore, an accurate rocking curve profile can be measured, and a precise analysis of the rocking curve can be performed. For example, when used together with rocking curve simulation, the crystal structure can be precisely evaluated, and when used in a lattice constant measurement such as a bond method, highly accurate measurement can be performed. Also,
In X-ray topographic imaging, a high-resolution topographic imaging can be performed by adjusting the crystal tilt angle accurately.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. Crystal tilt angle adjusting method of a single crystal sample in X-ray diffraction measurement according to this embodiment, first of all, the crystal inclination angle α is varied by [Delta] [alpha] _1, of ± [Delta] [omega ₁ against ω-axis per the change A rocking curve is measured a plurality of times in the angular range with a scan speed of v ₁ (arcsec) per minute. One of the peak intensity, half width or peak position (angle) of each of the measured rocking curves is plotted against the crystal inclination angle α. Then, the plotted result is fitted to a function curve having one peak value, such as Gaussian or Lorenzian. The crystal inclination angle alpha which corresponds to the position of the vertex of the function curve and alpha _1.

Next, before and after α ₁ obtained above, ± Δα (Δ
α~Δα _1/2) similarly measured multiple times rocking curve in an angular range of. That is, the crystal tilt angle α is Δα
₂ (Δα ₁ > Δα ₂ ), and for each change, ω
A rocking curve is measured a plurality of times at a scan speed of v ₂ (arcsec) per minute in an angle range of ± Δω ₂ with respect to the axis. One of the measured peak intensities, half widths, or peak positions (angles) of the plurality of rocking curves is plotted against the crystal inclination angle α. Then, the plotted result is fitted to a function curve having one peak value, such as Gaussian or Lorenzian. The adjustment is performed using the crystal inclination angle α corresponding to the position of the vertex of the function curve.

Here, the feature of the present invention is that the above-described parameters, Δα ₁ , Δα ₂ , Δω ₁ , and Δω ₁ are satisfied so as to satisfy the following equations (1) to (3) at the time of the above-described adjustment method. Δ
consists in setting ω ₂ , v ₁ and v ₂ .

[0019] _{(1) Δα 1/20 ≦} Δα 2 ≦ Δα 1/1
_{0 (2) Δω 1/10} ≦ Δω 2 ≦ Δω 1/4 (3) v 1/10 ≦ v 2 ≦ v 1/3 present inventors have conducted extensive studies, when performing adjustment method described above , Δα ₁ , Δα ₂ , Δω ₁ , Δω ₂ , v ₁ and v ₂ are set so as to satisfy the equations (1) to (3), and the crystal tilt angle α is accurately and quickly adjusted. I found that I can do it. Therefore, according to the adjustment method according to the present embodiment, even when the crystal inclination angle α at the start of the adjustment is significantly different from the true value, the measurement time does not increase, The crystal tilt angle α can be adjusted.

Instead of scanning ω at v ₁ (arcsec) per minute, step scanning of step width Δθ ₁ and counting time t ₁ is performed, and ω is scanned at v ₂ (arcsec) per minute. Instead, in the adjustment method of performing the step scanning of the step width Δθ ₂ and the counting time t ₂ , the above-described parameters Δα ₁ and Δα ₂ so as to satisfy the following equations (4) to (7). , Δω ₁ , Δ
Even when ω ₂ , Δθ ₁ , Δθ ₂ , t ₁ and t ₂ are set, the same effect can be obtained.

[0021] _{(4) Δα 1/20 ≦} Δα 2 ≦ Δα 1/1
_{0 (5) Δω 1/10} ≦ Δω 2 ≦ Δω 1/4 (6) Δθ 1/5 ≦ Δθ 2 ≦ Δθ 1/2 (7) (Δθ 1 / t 1) / 10 ≦ (Δθ 2 / t 2 ) ≤
(Δθ ₁ / t ₁ ) / 3

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the above-described embodiment of the present invention will be described below.

(Example 1) Plane orientation (111), specific resistance 1
A sample of 1.5 × 1.5 cm was cut out from a high-purity FZ-Si single crystal wafer of 000 (Ω · cm), and a surface layer of about 15 μm was removed by chemical etching. Then, the sample was set on a goniometer head of an X-ray diffraction apparatus. . Using the Kα ₁ characteristic X-ray of Cu, the crystal inclination angle α is set with respect to the Si (444) plane.
Was adjusted.

First, assuming that the adjustment start state (α = α ₀ ) was α = 0, the crystal tilt angle α was changed by Δα ₁ = 0.2 °, and a rocking curve was measured for each change.
The measurement is performed with a step width Δθ ₁ = 1 ”and an X-ray counting time t ₁ =
By the 0.3 second step scanning method, ± Δω ₁ =
The measurement was performed in a measurement angle range of ± 50 ". The peak intensities of the measured plurality of rocking curves were plotted against the crystal inclination angle α, and the obtained curve was fitted to Gaussian to obtain a position indicating the apex of the curve ( α = α ₁ ).

Next, in the vicinity of α = α ₁ , the crystal inclination angle α was changed by Δα ₂ = 0.02 °, and a rocking curve was measured for each change. Measurement is step width Δ
The measurement was performed in a measurement angle range of ± Δω ₂ = ± 10 ″ by a step scanning method in which θ ₂ = 0.2 ″ and X-ray counting time t ₂ = 0.4 seconds. The peak intensity of the measured rocking curve is plotted against the crystal inclination angle α, the obtained curve is fitted to Gaussian, and the peak position of the curve (α =
α _θ ) was obtained, and α _θ = −0.18 ° was obtained.

Therefore, a position where α was inclined to the minus side by 0.18 ° from the initial state (α = α ₀ ) was determined as a state where the crystal inclination angle was optimally adjusted. The accuracy of this adjustment was confirmed using the second method described in the conventional example. That is, a light-receiving aperture is placed at a position separated from the sample by an appropriate distance on the rotation plane of the sample (ω axis), and two half-slits (upper half and lower half) are alternately provided at the position of the light-receiving aperture. As a result of the measurement, the X-ray intensities of the case using the upper half slit and the case using the lower half slit showed an extremely good agreement. Furthermore, in this setting, the bond method (precise measurement method of lattice constant of single crystal: Acta
Cryst., 13 (1960 (814))), the lattice constant was determined, and a = 5.431074 angstroms was obtained.
It was in good agreement with the literature value (J. Appl. Phys., 56 (1984) 314).

(Example 2) Plane orientation (100), additive-free C
A sample of 1 × 1 cm was cut out from the Z-Si single crystal wafer, and after removing about 23 μm of the surface layer by chemical etching, the sample was set on a goniometer head of an X-ray diffraction apparatus. C
The crystal tilt angle α was adjusted with respect to the Si (400) plane using the Kα ₁ characteristic X-ray of u.

First, assuming that the starting state of adjustment (α = α ₀ ) is α = 0, the crystal tilt angle α was changed by Δα ₁ = 0.2 °, and a rocking curve was measured for each change.
The measurement was performed with a step width Δθ ₁ = 0.5 ″ and an X-ray counting time t ₁
= By 0.3 sec step scanning method, ± [Delta] [omega ₁
The peak position of each of a plurality of measured rocking curves was read with a rotary encoder and plotted against the crystal tilt angle α, and the obtained curve was fitted to Gaussian to obtain the peak of the curve. (Α = α ₁ ) was determined.

Next, in the vicinity of α = α ₁ , the crystal tilt angle α was changed by Δα ₂ = 0.02 °, and a rocking curve was measured for each change. Measurement is step width Δ
The measurement was performed in a measurement angle range of ± Δω ₂ = ± 5 ″ by a step scanning method in which θ ₂ = 0.2 ″ and X-ray counting time t ₂ = 0.4 seconds. The peak position of the measured rocking curve was read by a rotary encoder, plotted against the crystal inclination angle α, and the obtained curve was fitted to Gaussian to determine the vertex position of the curve (α = α _θ ).
αθ = 0.06 ° was obtained.

Therefore, the position where the crystal tilt angle α was tilted to the plus side by 0.06 ° from the initial state (α = α ₀ ) was determined as the state where the crystal tilt angle α was optimally adjusted. The accuracy of this adjustment was confirmed using the second method described in the conventional example. That is, a light-receiving aperture is placed at a position separated from the sample by an appropriate distance on the rotation plane of the sample (ω axis), and two half-slits (upper half and lower half) are alternately provided at the position of the light-receiving aperture. As a result, the X-ray intensities of the case where the upper half slit was used and the case where the lower half slit were used showed an extremely good agreement. Further, in this setting, when the lattice constant was determined by the bond method (precise measurement method of lattice constant of single crystal: Acta Cryst., 13 (1960) 814), a = 5.431077 angstroms was obtained. .Appl.Phys., 56 (1984) 314).

In the following embodiment, Δα ₁ , Δα ₂ , Δω
Only the values of ₁ , Δω ₂ , Δθ ₁ , Δθ ₂ , t ₁ and t ₂ are shown.

(Example 3) Using a Kα ₁ characteristic X-ray of Cu, (42) of a Si single crystal having a sample surface of (100) was used.
2) The crystal inclination angle α was adjusted with respect to the plane (glare angle <
Bragg angle).

In this case, Δα ₁ = 0.2 °, Δα ₂
= 0.02 °, Δω ₁ = 50 ″, Δω ₂ = 10 ″, v ₁
= 200 ″ / min, v ₂ = 30 ″ / min, or Δα ₁
= 0.2 °, Δα ₂ = 0.02 °, Δω ₁ = 50 ″, Δ
ω ₂ = 10 ″, Δθ ₁ = 1 ″, Δθ ₂ = 0.5 ″, t ₁
= 0.3 seconds, t ₂ = 0.1 seconds,
It was able to measure accurately in a short time.

Example 4 Using a Kα ₁ characteristic X-ray of Cu, the sample surface was (42) of a Si single crystal of (100).
2) The crystal inclination angle α was adjusted with respect to the plane (glance angle>
Bragg angle).

In this case, Δα ₁ = 0.2 °, Δα ₂
= 0.02 °, Δω ₁ = 50 ″, Δω ₂ = 5 ″, v ₁ =
200 ″ / min, v ₂ = 30 ″ / min, or Δα ₁ =
0.2 °, Δα ₂ = 0.02 °, Δω ₁ = 50 ″, Δω
₂ = 5 ″, Δθ ₁ = 1 ″, Δθ ₂ = 0.5 ″, t ₁ =
When the measurement was performed under the conditions of 0.3 seconds and t ₂ = 0.4 seconds, accurate measurement was possible in a short time.

[0036] (Example 5) using the K [alpha ₁ characteristic X-ray of Cu, the sample surface of the Si single crystal is (100) (51
1) The crystal inclination angle α was adjusted with respect to the plane (glare angle <
Bragg angle).

In this case, Δα ₁ = 0.1 °, Δα ₂
= 0.01 °, Δω ₁ = 30 ″, Δω ₂ = 4 ″, v ₁ =
200 ″ / min, v ₂ = 30 ″ / min, or Δα ₁ =
0.1 °, Δα ₂ = 0.01 °, Δω ₁ = 30 ″, Δω
₂ = 4 ″, Δθ ₁ = 1 ″, Δθ ₂ = 0.5 ″, t ₁ =
When the test was performed under the conditions of 0.15 seconds and t ₂ = 0.4 seconds,
It was able to measure accurately in a short time.

Example 6 Using a Kα ₁ characteristic X-ray of Cu, (51) of a Si single crystal having a sample surface of (100) was used.
1) The crystal inclination angle α was adjusted with respect to the plane (glance angle>
Bragg angle).

In this case, Δα ₁ = 0.2 °, Δα ₂
= 0.01 °, Δω ₁ = 30 ″, Δω ₂ = 5 ″, v ₁ =
200 ″ / min, v ₂ = 30 ″ / min, or Δα ₁ =
0.2 °, Δα ₂ = 0.02 °, Δω ₁ = 50 ″, Δω
₂ = 5 ″, Δθ ₁ = 1 ″, Δθ ₂ = 0.5 ″, t ₁ =
When the measurement was performed under the conditions of 0.3 seconds and t ₂ = 0.4 seconds, accurate measurement was possible in a short time.

(Example 7) Using a Kα ₁ characteristic X-ray of Cu, a sample surface (100) of a Si single crystal (44) was used.
4) The crystal inclination angle α was adjusted with respect to the plane (glance angle <
Bragg angle).

In this case, Δα ₁ = 0.2 °, Δα ₂
= 0.02 °, Δω ₁ = 50 ″, Δω ₂ = 10 ″, v ₁
= 200 ″ / min, v ₂ = 30 ″ / min, or Δα ₁
= 0.2 °, Δα ₂ = 0.02 °, Δω ₁ = 50 ″, Δ
ω ₂ = 5 ″, Δθ ₁ = 1 ″, Δθ ₂ = 0.5 ″, t ₁ =
When the measurement was performed under the conditions of 0.3 seconds and t ₂ = 0.4 seconds, accurate measurement was possible in a short time.

Example 8 Using a Kα ₁ characteristic X-ray of Cu, (44) of a Si single crystal having a (100) sample surface was used.
4) The crystal inclination angle α was adjusted with respect to the plane (glance angle>
Bragg angle).

In this case, Δα ₁ = 0.2 °, Δα ₂
= 0.02 °, Δω ₁ = 50 ″, Δω ₂ = 10 ″, v ₁
= 200 ″ / min, v ₂ = 30 ″ / min, or Δα ₁
= 0.2 °, Δα ₂ = 0.02 °, Δω ₁ = 50 ″, Δ
ω ₂ = 5 ″, Δθ ₁ = 1 ″, Δθ ₂ = 0.5 ″, t ₁ =
When the measurement was performed under the conditions of 0.3 seconds and t ₂ = 0.4 seconds, accurate measurement was possible in a short time.

From the above examples, it was confirmed that the crystal tilt angle adjusting method according to the present embodiment can easily and accurately and quickly adjust the crystal tilt angle.

[0045]

As described above, according to the present invention,
The crystal tilt angle can be easily and accurately and quickly adjusted. Therefore, rocking curve profile analysis,
In a lattice evaluation such as a bond method or a crystal evaluation such as an X-ray topography, a large number of samples can be accurately evaluated in a short time.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an X-ray diffraction apparatus used for general X-ray diffraction measurement.

FIG. 2 is a cross-sectional view of the single crystal sample 1 shown in FIG. 1 as viewed from a direction indicated by A in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Single crystal sample 3 X-ray tube 5 Counter tube 7 Surface of single crystal sample 9 Lattice plane

Claims (2)

[Claims] 1. A method for adjusting a crystal tilt angle formed by a plane perpendicular to a rotation axis (ω axis) of a single crystal sample and a normal vector of a single crystal lattice plane during X-ray diffraction measurement of the single crystal, the crystal tilt angle is changed by [Delta] [alpha] _1, a range of ± [Delta] [omega ₁ per the change, the ω plurality measures the rocking curve of the scanning speed v ₁ about an axis, rocking curve respective peak intensities of the plurality of the half-value width , One of the peak positions or peak angles is plotted against the crystal tilt angle, and the result is fitted to an arbitrary first function curve having one peak value, and the peak of the first function curve is plotted. A first step of setting the crystal tilt angle corresponding to the position to α _1, and changing the crystal tilt angle by Δα _{2 in} the vicinity of the α ₁ obtained in the first step, and for each change, ± in the range of [Delta] [omega _2, liked for the ω axis Down speed v plurality measure rocking curve _2, the rocking curve respective peak intensities of the plurality of half width, plotted one against the crystal inclination angle of the peak position or peak angle, the result 1 A second function curve fitting an arbitrary second function curve having a peak value, and adjusting using a crystal tilt angle corresponding to a position of a vertex of the second function curve, wherein Δα ₁ , Δα ₂ , Δω ₁ , Δω ₂ , v ₁ and v
_{2, Δα 1/20 ≦ Δα 2} ≦ Δα 1/10, Δω 1 /
_{10 ≦ Δω 2 ≦ Δω 1/} 4, v 1/10 ≦ v 2 ≦ v 1 /
3. A method for adjusting a crystal tilt angle of a single crystal sample in X-ray diffraction measurement, characterized by satisfying 3. 2. A method for adjusting a crystal tilt angle formed by a plane perpendicular to a rotation axis (ω axis) of a single crystal sample and a normal vector of a single crystal lattice plane during X-ray diffraction measurement of the single crystal, the crystal tilt angle is changed by [Delta] [alpha] _1, a range of ± [Delta] [omega ₁ per the change, for the ω axis step width Δ
θ ₁ , a plurality of rocking curves are measured by performing step scanning of the counting time t ₁ , and _one of the peak intensity, half width, peak position or peak angle of each of the plurality of rocking curves is determined with respect to the crystal tilt angle. And fitting the result to an arbitrary first function curve having one peak value, and setting the crystal inclination angle corresponding to the position of the vertex of the first function curve to α _1. When, in the first vicinity of the alpha ₁ obtained in step, said crystal tilt angle is changed by [Delta] [alpha] _2, in a range of ± [Delta] [omega ₂ per the change, step width [Delta] [theta] ₂ for the ω axis, counting time a plurality measured rocking curve by performing the steps scanning t _2, the rocking curve respective peak intensities of the plurality of half-width, one pair in the crystal inclination angle of the peak position or peak angle A second function curve fitting an arbitrary second function curve having one peak value, and adjusting using a crystal tilt angle corresponding to a position of a vertex of the second function curve; and Δα ₁ , Δα ₂ , Δω ₁ , Δω ₂ , Δθ ₁ , t ₁ ,
[Delta] [theta] ₂ and t _{2 is, Δα 1/20 ≦ Δα 2} ≦ Δα 1/1
_{0, Δω 1/10 ≦ Δω} 2 ≦ Δω 1/4, Δθ 1/5 ≦
_{Δθ 2 ≦ Δθ 1/2,} (Δθ 1 / t 1) / 10 ≦ (Δθ
₂ / t ₂ ) ≦ (Δθ ₁ / t ₁ ) / 3, a method for adjusting a crystal tilt angle of a single crystal sample in X-ray diffraction measurement.