JPH05107203A - X-ray apparatus for evaluating surface condition of sample - Google Patents

Abstract

PURPOSE:To evaluate surface the conditions of a sample such as crystal orientation in a short time by making linear parallel X-ray beams fall on the sample and by detecting onedimensionally only a parallel component in diffracted beams. CONSTITUTION:An incident angle OMEGA around an axis OMEGA perpendicularly intersecting a detecting surface B of a sample S, a tilt chi around the axis and an angle 2theta of diffraction being set, thin and linear parallel X-ray beams I located on the detecting surface B formed by incident X rays I and diffracted X rays R are applied onto the sample S and only a parallel component R of the diffracted rays is measured by a one-dimensional X-ray detector D. While the sample S is moved minutely in the direction of the axis (y), two-dimensional information on the surface of the sample S can be measured only by one- dimensional scanning and a measuring time can be shortened sharply.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for evaluating the state of the crystal orientation of each region on the surface of a crystal sample such as a single crystal aggregate, and particularly to an apparatus for evaluating the state of the sample surface using linear X-rays. Regarding

[0002]

2. Description of the Related Art Research and development for coating a surface of a single crystal sample such as a high temperature superconductor or a different material has been actively conducted. The X-ray diffraction technique is used to evaluate the surface of the prepared sample, and when the sample is crystalline, the items to be evaluated are as follows.

It is investigated how the crystals are distributed in each place of the sample whether it is a single single crystal, an aggregate of single crystals, a polycrystal, or a mixture thereof.

In the case of a single single crystal sample, it is investigated how the lattice strain is distributed.

In the case of a single crystal aggregate, the shape, orientation, and distribution of each single crystal are examined.

As a conventional technique for investigating such evaluation, there is an X-ray topography method for observing a distribution of diffracted X-rays by irradiating a collimated thick parallel X-ray beam on the entire surface of a sample,
Although it is applied to the case of the above, there is a limit that it is possible to measure only a very small azimuth change or a minute strain in a state where the sample surface and the diffraction surface are not displaced.

Further, as a method for investigating a large orientation change and strain of each single crystal distributed on the sample, a point-like X-ray beam collimated to a minute size is two-dimensionally distributed at each position on the sample surface. It is known to irradiate and change the orientation of the sample so that diffraction occurs at each point, but this requires a very long measurement time because it requires two-dimensional scanning over the sample in minute steps. Not practical.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of such a situation, and an object thereof is a thin linear parallel X-ray existing on a plane formed by incident X-rays and diffracted X-rays. The beam is incident on the sample, and the one-dimensional X-ray detector is used to detect only the parallel component in the diffracted beam from the linear portion of the sample surface that is irradiated with X-rays. An object of the present invention is to provide a device capable of evaluating the surface condition in a relatively short time.

[0009]

An X-ray sample surface state evaluation apparatus of the present invention which achieves the above object defines a plane including a sample surface as a sample surface, and defines an x axis and ay axis orthogonal to each other in the sample surface. , A plane that includes the x-axis and intersects the sample surface and that includes the linearly parallel incident X-ray beam and the linearly parallel diffracted X-ray beam is used as a detection surface, the sample can be moved in the y direction, and the y-axis is approximately the center of the surface. A sample mounting means mounted so as to pass therethrough is provided, and is parallel to a linear region along the x-axis of the sample surface in the detection plane X
An X-ray irradiating means for irradiating a linear incident beam is provided, and among the diffracted X-rays diffracted from the linear X-ray irradiation region on the sample surface, only the parallel X-beam diffracted at a predetermined diffraction angle 2θ in the detection plane is displayed. A means for taking out and detecting the one-dimensional intensity distribution thereof, which comprises a one-dimensional X-ray detecting means capable of adjusting the detection diffraction angle 2θ with respect to the incident beam around the ω axis passing through the origin and orthogonal to the detection surface, To adjust the relative angle ω of the x-axis to X, around the ω-axis.
A first angle adjusting means for adjusting the rotation angle of one or both of the beam irradiating means and the one-dimensional X-ray detecting means is provided, and further, the angle χ between the sample surface and the ω axis is adjusted so as to be adjusted around the x axis. A second angle adjusting means for adjusting a rotation angle of one or both of the sample attaching means, the X-ray irradiating means and the one-dimensional X-ray detecting means is provided.

[0010]

According to the present invention, it is not necessary to perform two-dimensional scanning of the sample surface in order to collect the two-dimensional information of all positions on the sample surface, and the sample is simply moved in the direction orthogonal to the linear X-ray irradiation region. It only requires one-dimensional scanning, and the direction of the sample is relatively changed around two axes so that diffraction occurs, but the X-ray irradiation area of the sample does not change and the X-ray irradiation system and the detection system shift. There is no. Furthermore, since the linear information on the sample surface can be collected at the same time, the measurement time can be greatly reduced.

[0011]

EXAMPLES Examples of the X-ray sample surface condition evaluation apparatus of the present invention will be described below with reference to the drawings. Before explaining the embodiments, the principle of the device of the present invention will be described with reference to FIG. The figure (a) is a diagram showing a state in the detection surface of this device, the figure (b) is a diagram of the figure (a) seen from the arrow L direction, and the figure (c) is a plan view of the sample part. Yes, the dotted line in FIG. 7C shows a state in which the sample is moved by a minute distance Δy in the y direction.

A plane including the surface of the sample S is referred to as a sample surface A,
An x-axis and a y-axis that are orthogonal to each other are defined in the plane A as shown in the drawing, and the intersection is defined as an origin O. A plane B that includes the x-axis and intersects the sample surface A and that includes a linear parallel incident X-ray beam I and a linear parallel diffracted X-ray beam R described later is defined as a detection surface. The axis orthogonal to the detection surface B at the origin O is defined as the ω axis.

In the present invention, in the detection plane B,
The parallel collimated linear X-ray beam I is applied to the sample S.
Irradiate on the x-axis of the surface. Linear X on the x-axis of the sample S surface
Of the diffracted X-rays diffracted from the X-ray irradiation region, only the linear parallel diffracted X-ray beam R on the detection surface B is taken out and the one-dimensional X-ray detector D fixed to the diffraction negative 2θ of a certain diffracted line Detect the one-dimensional intensity distribution. Since this one-dimensional intensity distribution uses a parallel beam optical system, the intensity from each position on the surface of the sample S on the x-axis can be detected in a one-to-one correspondence with the detection position of the detector D. .. That is, the origin O
When the detection position of the diffraction line from above at the detector is O _D and the detection position of the detector _D is x _D as shown in the drawing, the detection position x _D and the sample position x _S are as follows: x _D = x _S The relationship is sin (2θ−ω). FIG. 2 shows the detected one-dimensional intensity distribution in a stylized manner.

As is well known in X-ray diffraction, a diffraction line from a single crystal is a strong diffraction line with a narrow half width as compared with a diffraction line from a polycrystal. In the case of a single crystal, diffraction occurs only when it is in the orientation that satisfies the diffraction condition, but in the case of a polycrystal, it is an aggregate of microcrystals with random orientation, so it is related to the orientation of the sample. Bragg diffraction condition 2d sin θ = λ
Diffract in the direction.

Therefore, it can be seen from the diffraction line peak intensity whether the diffraction line is from a single crystal or polycrystal. In FIG. 2, the detection position where the diffraction line is detected is from x _D3 to x _D4 , and the position x _{S3 to} x _S4 on the sample is one single crystal, and the detection position where the weak diffraction line is detected. From x _{D1 to} x _D2 , it can be determined that the portions at positions x _{S1 to} x _S2 on the sample are polycrystalline. The other portions with weak intensity are single crystals, but the orientations do not match, and therefore, the portions where diffraction does not occur. As to this portion, the shape and orientation of the single crystal can be examined by changing the orientation of the sample S by ω and χ rotation and performing the same measurement as described later.

In FIG. 1, the sample S is sequentially moved in the y direction by a minute distance Δy, and the detection of the same one-dimensional intensity distribution of the diffracted X-rays is repeated to obtain a two-dimensional image as shown in FIG. 3 on the entire surface of the sample S. A general distribution diagram is required. In FIG. 3, region I is considered to be a single crystal oriented in a direction satisfying the diffraction condition, region II is a polycrystalline substance, and region III is considered to be a single crystal oriented in a direction not satisfying the diffraction condition. It is not always a crystal. This movement of the sample S is performed on the y-axis, but the linear X-ray irradiation region of the sample S (FIG. 1C) is always on the x-axis in the detection surface B, so that even if the sample S is moved. , The X-ray optical system does not change.

As for the portion facing the azimuth which does not satisfy the diffraction conditions shown in FIGS. 2 and 3, the sample S is rotated by ω rotation around the ω axis and χ rotation around the x axis to change the orientation. By performing the same measurement as described above in the above state, a two-dimensional distribution state diagram as shown in FIG. 4 is obtained. Since the region II is a polycrystalline body, it is also a region that is diffracted this time, and the region IV is a single single crystal that satisfies the diffraction condition in this orientation. Further, the region I shown by the dotted line is not visible this time. Like the region III, the region III 'is considered to be a single crystal oriented in an orientation that does not satisfy the diffraction condition, but it is not limited to the single crystal. Also in this case, the movement of the sample S in the y-axis direction does not change the X-ray optical system.

When several measurements at ω and χ are performed and the obtained two-dimensional distribution state diagrams are synthesized, a two-dimensional distribution state diagram as shown in FIG. 5 is obtained, and each single crystal on the surface of the sample S is obtained. The shape and its orientation can be obtained. Further, the shape of the polycrystalline portion can be obtained. Thus, the crystalline state distribution at each location on the surface of the sample S,
The shape and orientation of each single single crystal and its distribution can be investigated.

Further, if the fixed 2θ angle of the one-dimensional X-ray detector D is changed to another diffraction angle and the same measurement is performed, the orientation of different diffraction planes can be found for each single single crystal. The three-dimensional orientation of the single crystal is also required.

Further, there are the following advantages in the lattice strain distribution measurement (lattice constant distribution measurement) in the case of a single single crystal sample. Generally, the surface of the single crystal sample and the diffraction surface are deviated from each other, but at this time, the sample S is tilted in the azimuth that satisfies the diffraction condition by the rotation of ω and χ. In the conventional X-ray topography apparatus, if the above-mentioned deviation is large, only the microscopic region where the diffraction image is not distorted becomes the measurement region. Therefore, the measurement of each microscopic region of the sample S is performed two-dimensionally at each position of the sample S. I had to. In the present invention, the linear region can be measured at the same time even when the deviation is large, and the data of the entire region can be obtained by one-dimensional scanning of the sample S in the y-axis direction. Even if the orientation of the sample crystal is largely changed using ω and χ, y of the sample S is changed.
Since the X-ray optical system does not change due to the axial scanning, there is no distortion of the two-dimensional diffraction image, which enables the above measurement.

By the way, in order to generate a parallel collimated linear X-ray beam I in the detection plane B,
For example, as shown in FIG. 1, a linear X-ray source 1 is arranged in the detection surface B so as to intersect with the incident direction, and a collimator 2 such as a solar slit that extracts only the X-rays directed in the incident direction in front of the linear X-ray source 1. May be arranged, and further, the incident side slit 3 including the detection surface B and having a linear slit along the detection surface B may be arranged in front thereof. Further, in order to extract only the parallel beam R diffracted in the predetermined direction within the detection plane B among the diffracted X-rays diffracted from the linear X-ray irradiation region on the surface of the sample S, a predetermined X-ray irradiation region is used. A light-receiving side slit 4 having a linear slit extending along the detection surface B and having a length for passing a diffraction line directed in the diffraction direction is arranged behind the X-axis in the diffraction angle 2θ direction.
It suffices to arrange a collimator 5 such as a solar slit that takes out only the line. The one-dimensional X-ray detector D is not particularly limited, and PSPC (Position Sensitive Proportio)
Any known detector such as a nal counter) or CCD can be used.

Next, specific examples of the present invention will be described. FIG. 6 is a perspective view of a main part of the first embodiment, and FIG. 7 is a perspective view of a sample table portion in a state where the sample S is rotated by a χ angle about the x axis. The same reference numerals are attached. In this embodiment, the sample S is placed on the sample table 11 of the biaxial goniometer 10, the sample S is tilted around the ω axis, and the incident angle ω formed by the x axis and the incident beam I is adjusted.
Further, the sample S is tilted around the x-axis passing through the sample surface to adjust the angle χ formed by the detection surface (FIG. 1) with respect to the sample surface. For this purpose, a cylindrical surface centering on the x-axis is provided on the sample table 11 rotating about the ω-axis,
Intermediate stage 16 having a cylindrical lower surface with the same radius thereon
Of the intermediate stage 16 with respect to the sample stage 11
The rotation angle around the axis is adjusted by the tilt knob 17. X stage 1 on the intermediate stage 16
4 is adjustably mounted in the x direction, and its position is adjusted by the X knob 15. Further, the Y stage 12 is mounted on the X stage 14 so as to be adjustable in the y direction.
The position of each detection is moved by the rotation of. Also, x
The sample table 1 so that the intersection of the axis and the ω-axis is located on the surface of the sample S.
A Z knob 21 for adjusting the z-direction height of 1 is also provided. In addition, the light-receiving side slit 4, the solar slit 5, 1
The diffracted beam R detection system including the dimensional X-ray detector D is adjustable in angle around the ω axis by an adjusting and fixing mechanism (not shown), and is adjusted by the size of the diffraction angle 2θ. The incident beam I irradiation system including the linear X-ray source 1, the solar slit 2 and the incident side slit 3 is fixed to the apparatus, but the angle can be adjusted around the ω axis as necessary. In the figure, reference numeral 20 is an X-ray tube shield of the linear X-ray source 1, 22 is a limiting slit for limiting the light receiving area of the one-dimensional X-ray detector D, and 23 is a reference plane jig.

With the above structure, the sample S is y
The position is set to the direction start position, and the one-dimensional intensity distribution of the diffracted X-rays from the x-direction linear X-ray irradiation region at the y position is detected by the one-dimensional X-ray detector D for the predetermined ω, 2θ, and χ. , The sample S is moved a small distance in the y direction and the detection is repeated in the same manner, whereby the two-dimensional distribution information such as the crystal orientation of the surface of the sample S determined by the values of ω, 2θ, and χ is obtained. Two-dimensional distribution information is similarly obtained for another set of values of ω, 2θ, and χ.

By the way, as shown in FIGS. 6 and 7, when the sample S is attached to a goniometer and rotated about an axis, the sample S is heated, cooled, pulled, compressed, bent, vacuum, gas atmosphere, magnetic field. , Surface condition 2 while applying an electric field, etc.
It is not easy to detect the dimensional distribution. Therefore, as shown in the schematic view of FIG. 8, the sample S is placed on the fixed sample table 30 which can be adjusted in the x, y, and z directions, and the linear X
An X-ray irradiation device 31 including a radiation source 1, a solar slit 2, and an incident side slit 3 and a light receiving side slit 4, a solar slit 5, and a one-dimensional X-ray detection device 32 including a one-dimensional X-ray detector D are arranged on the x-axis. It can be deformed so as to be attached to a circular arm 33 which is rotatable about a center and which has an origin O as a center so that the incident angle ω and the diffraction angle 2θ can be adjusted. By doing so, only the movement of the sample S in the y direction is limited to the sample table 3
0, the surface of the sample S is always kept horizontal and its inclination disappears. Therefore, means for applying heating, cooling, pulling, compression, bending, vacuum, gas atmosphere, magnetic field, electric field, etc. to the sample S. Can be easily installed together, and these atmospheres can be changed while detecting the surface condition. In FIG. 8, a rotary shaft 34 is fixed to the circular arm 33, and the rotary shaft 34 is configured to rotate around the x axis in a fixed base 35.

In FIGS. 1 and 6 to 8 described above, solar slits are used as the collimators 2 and 5 of the X-ray irradiation system and the X-ray detection system, but instead, Bragg diffraction on the crystal plane is performed. It is possible to use a crystal monochromator (made of silicon crystal, germanium crystal, graphite, etc.) for extracting X-rays of a specific wavelength diffracted in a specific direction. FIG. 9 is a schematic diagram in that case, and the reference numerals 2'and 5'represent a crystal monochromator. The monochromator 5'is constructed by cutting parallel to the crystal plane 6, and the monochromator 2'is an asymmetric cut monochromator cut across the crystal plane 6. In the former, the incident beam and the diffracted beam have the same cross-sectional size, but in the latter,
Since the cross section of the diffracted beam has a property of being deformed in the diffraction direction as compared with the incident beam, if an asymmetric cut monochromator 2'is used as a collimator of the X-ray irradiation system as shown in FIG. Since the length can be increased, a larger sample S can be measured. As for the monochromator 5 ', the cross section of the diffracted beam entering the detector D can be enlarged or reduced by using an asymmetric cut monochromator.

In the above, the orientation of the crystals constituting the sample S can be completely determined by rotating the sample S around the normal line of its surface and performing the same measurement.

Although some embodiments of the X-ray sample surface condition evaluation apparatus of the present invention have been described above, the present invention is not limited to these embodiments and various modifications can be made.
For example, in FIG. 6, with the sample surface facing downward, X from the bottom
It can be adapted to irradiate a line.

[0028]

As is apparent from the above description, the X-ray sample surface condition evaluation apparatus of the present invention has the following effects.

Since the parallel linear X-ray beam on the plane formed by the incident X-ray and the diffracted X-ray is used and only the parallel component of the diffraction line is measured by the one-dimensional X-ray detector, the orientation of the sample is Two
Even if it is changed in the axial direction, the two-dimensional information of the sample can be measured by only one-dimensional scanning, and the measurement time can be greatly reduced.

In the case of a single crystal, even if the surface of the sample and the diffractive surface are largely deviated, the distribution of the lattice strain and the change of the lattice constant within the sample can be measured.

In the case of an aggregate of single crystals, a large change in orientation of each single crystal can also be measured.

It is possible to measure in-plane distribution of defects such as single crystal and amorphous.

In the case of an aggregate of a single crystal and a polycrystal, its distribution can be measured.

If a beam having a higher degree of parallelism is used by using a crystal monochromator, highly accurate minute displacement measurement can be performed.

The use of the asymmetric cut crystal monochromator enables the measurement of larger samples.

If the sample is kept horizontal, the orientation distribution of the liquid sample (liquid crystal or the like) can be measured.

In the case of a single single crystal, it can be investigated whether the sample is a flat plate or curved, and if curved, how curved.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the principle of an X-ray sample surface state evaluation device of the present invention.

FIG. 2 is a diagram stylistically showing a detected one-dimensional diffraction X-ray intensity distribution.

FIG. 3 is a two-dimensional distribution state diagram on the entire surface of a sample in a specific orientation.

FIG. 4 is a two-dimensional distribution state diagram on the entire surface of the sample in another orientation.

FIG. 5 is a synthetic two-dimensional distribution state diagram.

FIG. 6 is a perspective view of a main part of the first embodiment of the present invention.

FIG. 7 is a perspective view of a sample stage portion in a state of being rotated by χ angle in FIG.

FIG. 8 is a schematic diagram of a second embodiment.

FIG. 9 is a schematic diagram of a configuration when a crystal monochromator is used as a collimator.

[Explanation of symbols]

 S ... Sample A ... Sample surface B ... Detection surface I ... Incident parallel X-ray beam R ... Diffraction parallel X-ray beam D ... One-dimensional X-ray detector 1 ... Linear X-ray source 2 ... Solar slit 3 ... Incident side slit 4 ... Light receiving side slit 5 ... Solar slit 10 ... Goniometer 11 ... Sample stage 12 ... Y stage 13 ... Motor 14 ... X stage 15 ... X knob 16 ... Intermediate stage 17 ... Aorinobu 20 ... X-ray tube shield 21 ... Z knob 22 ... Limit Slit 23 ... Reference plane jig

Claims (1)

[Claims] 1. A plane including a sample surface is defined as a sample surface, and an x-axis and a y-axis orthogonal to each other in the sample surface are defined, and a linear parallel incident X-ray beam and a linear parallel crossing the sample surface including the x-axis are defined. Diffraction X
A plane including the line beam is used as a detection surface, and a sample mounting means is provided for mounting the sample in the y direction so that the y axis passes through substantially the center of the surface, and a linear shape along the x axis of the sample surface in the detection surface. An X-ray irradiating means for irradiating a parallel X-ray incident beam to the area is provided, and a predetermined diffraction angle 2 in the detection plane among the diffracted X-rays diffracted from the linear X-ray irradiation area on the sample surface.
This is a means for extracting only the parallel X beam diffracted by θ and detecting its one-dimensional intensity distribution, and the detection diffraction angle 2θ for the incident beam can be adjusted around the ω axis that passes through the origin and is orthogonal to the detection surface. Dimensional X-ray detection means, and rotation of one or both of the sample attachment means, the X-ray irradiation means and the one-dimensional X-ray detection means about the ω axis so as to adjust the relative angle ω of the x-axis with respect to the incident beam. A first angle adjusting means for adjusting the angle, and further, an angle χ formed between the sample surface and the ω axis
To adjust the rotation angle of one or both of the sample attachment means, the X-ray irradiation means and the one-dimensional X-ray detection means around the x-axis. X-ray sample surface condition evaluation device.