JPH01127940A - X-ray diffractometer - Google Patents

Abstract

PURPOSE:To easily execute the adjustment of an optical system by supporting a divergence slit so as to be rotatable centering around the rotation center of a sample stage. CONSTITUTION:The divergence slit 7 is shifted from an X-ray optical path, a glancing angle is taken by adjusting the relative position relation of an X-ray source 1 and the rotation center O of a sample stage, and the X-ray optical path for connecting the X-ray source 1 and the rotation center O is determined. Subsequently, an adjustment is executed so that the X-ray source 1 and the rotation center O and the center (r) of an X-ray detecting part 8 are positioned on one X-ray optical path, and finally, adjustment is executed so that the center (d) of the slit 7 is positioned on the X-ray optical path. After such adjustment is executed, when a powder sample S is placed on the stage 5 and the stage 5 and the detecting part 8 are rotated in the speed ratio of one-to-two, while radiating X-rays from the X-ray source, the rotational angle (diffraction angle) of the detecting part 8 at the time when the detecting part 8 has detected a diffraction line from the sample S can be derived.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to an X-ray diffractometer (X-ray diffractometer).
The present invention relates to a fractoneter (fractoneter), and particularly relates to one that facilitates initial setting before starting measurement.

[Prior Art] FIG. 2 is a diagram showing a conventional X-ray diffractometer.

In the figure, reference numeral 1 is a linear X-ray source that is perpendicular to the plane of the drawing, and reference numeral 2 is a goniometer (goniometer).
oneter).

The goniometer 2 includes a base 3 and a goniometer main body 4 placed on the base 3.

This goniometer main body 4 has an angular velocity θ centered on point 0.
A sample stage 5 holds the sample S so that the center of the measurement surface of the sample S is located at the point O, and a sample stage 5 rotates at an angular velocity of 2θ about the point 0 in conjunction with the rotation of the sample stage 5. It is equipped with a rotating 2θ rotation section 6.

Further, the X-ray source 1 on the goniometer main body 4
A divergence slit 7 is arranged on the straight line connecting the point 0 and the point 0.

This divergence slit 7 is connected to the linear X-ray source 1.
The slit is arranged so that the center point d of the slit is located on a straight line connecting the X-ray source 1 and point O.

Further, a diffraction line detection section 8 is fixed to the 20-rotation section 6.

This diffraction ray detection unit 8 has a receiving slit 9 centered on the point O and arranged so that its center point r is located on a circle passing through the X-ray source 1 (diffractometer circle).
, an X-ray detector 10 and a scatter slit 11 for preventing scattered X-rays from entering the X-ray detector 10 from sources other than the sample S are respectively fixed.

The summer stand 3 is an X-ray machine equipped with the X-ray source 1.
It is placed on a work table 12 constituting a part of the radiation generating section, and its vertical position with respect to the work table 12 can be adjusted with an adjustment screw 31, and its center coincides with the X-ray source 1. As shown in FIG.
It is configured to be able to rotate around the X-ray source 1 by abutting the letter-shaped guide 32, and the angle setting I! It is configured so that it can be adjusted by a mechanism 32.

That is, this allows the X-ray source to The relative positional relationship between point 1 and point 0 can be adjusted to be appropriate.

Further, the goniometer main body 4 is configured to be rotatably adjusted around the point 0 by an adjustment screw mechanism 41, and the center point d of the divergence slit 7 is
m can be adjusted so that the X-ray source 1 is accurately positioned on the extension of the straight line connecting the point O and the point O.

Thereby, the center of the divergent X-rays passing through the divergence slit 7 always coincides with the point O, so that an optical system for measurement by the focusing method can be formed.

[Problems to be Solved by the Invention] By the way, the above-mentioned X-ray diffractometer can be used only when the angle of incidence of X-rays on the sample S is 0 degrees, that is, when the rotation angle of the sample stage 5 is 0 degrees. The optical system must be adjusted so that the rotation angle of the 2θ rotation unit 6 is also exactly 0 degrees.

In other words, at this time, the X-ray source 1, the center point d of the divergence slit 7, the point O, and the center point r of the receiving slit 9 must be exactly located on the same straight line. If this deviation occurs, it will appear as an error in subsequent measurements.

In this adjustment, first, when the rotation angles of the sample stage 5 and the 2θ concave rotation section 6 are respectively 0 degrees, the center point d of the divergence slit 7, point O, and the center point r of the receiving slit 9, that is, point d.

The three points 0 and r are mechanically adjusted in advance so that they are located on the same straight line.

Next, the straight line connecting the X-ray source 1 and the center point d of the divergence slit 7, that is, the angle that the X-ray emission direction makes with the target is a predetermined value (this angle is the glancing angle, and is set accurately). The base 3 is adjusted so that the angle is set at approximately 6 degrees.

Then, while emitting X-rays from the X-ray source 1, the X-rays that have passed through the center point d of the divergence slit 7 have a center point r of the receiving slit 9 when the rotation angle of the 2θ rotating section 6 is 0 degrees. The goniometer main body 4 is rotated and adjusted by the adjustment screw mechanism 41 while the X-ray detector 10 detects the X-ray intensity so that the X-ray detector 10 passes through the goniometer body 4.

As a result, the four points of the X-ray source 1, the center point d of the divergence slit 7, the point O, and the center point r of the receiving slit 9 should be located on the same straight line.

However, in general, it has been difficult to obtain sufficient accuracy as an X-ray optical system just by making such adjustments.

This is because in the adjustment, three points (X-ray source 1, point d) are checked and adjusted using X-rays out of the four points (X-ray source 1, point d, point O, and point r). and point r), and it has been confirmed that these three points are on the same straight line with the accuracy required by the X-ray optical system, but point O, which is the rotation center of the goniometer, is on this straight line. This has been mechanically confirmed (as mentioned above, mechanical adjustments have been made in advance so that points d, O, and r are on the same straight line), but X-ray optics Equivalence has not been confirmed systematically.

Therefore, in order to confirm this, for example,
The total intensity of the ray flux is detected by the X-ray detector 10, and then the
The intensity is measured when one side of the line bundle is cut off with a vertical line passing through point O as a boundary, and it is determined whether the intensity at this time is half of the total intensity.

As a result, if it is found that point 0 is not on the straight line, the mechanical adjustment and the adjustment of the three points using X-rays are performed again, and the above measurement is performed again. There is a drawback in that extremely sloppy adjustment work must be repeated until the system is located on the straight line.

Furthermore, even if an attempt was made to automate such an X-ray diffractometer through computer control, for example, it would be virtually impossible to automate even the complicated adjustments described above, so the benefits of automation would be halved. This was a major obstacle to automation.

An object of the present invention is to provide an X-ray diffractometer that eliminates the above-mentioned drawbacks. .

[Means for Solving the Problems] The present invention makes it extremely easy to adjust the X-ray optical system by supporting the divergence slit rotatably around the rotation center of the sample stage. , Specifically, it consists of an X-ray source, a divergence slit that regulates the divergence angle of the X-rays emitted from the X-ray source, and a divergence slit that directs the X-rays that have passed through the divergence slit toward a specific surface of the crystalline sample. a sample stage rotatably supporting the sample so that the sample can be incident at various angles; In an X-ray diffractometer, the X-ray diffractometer includes an X-ray detection means rotatably supported in a certain relationship with the rotation angle of the sample around the rotation center of the sample, the divergence slit being set at the rotation center of the sample. It has a structure in which it is rotatably supported around the center.

[Function] In the X-ray diffractometer with the above configuration, the X
While irradiating the sample with X-rays from the radiation source, the sample stage and the X-ray detection section are rotated at a speed ratio of 1:2, and at this time, the X-ray detection section detects diffraction rays from the sample. By determining the rotation angle of the X-ray detection unit, it is possible to obtain information indicating the lattice constant of the sample and other properties of the sample.

Incidentally, the adjustment of the X-ray optical system in the above apparatus can be performed as follows.

First, the divergence slit is removed from the X-ray optical path, and the relative positional relationship between the X-ray source and the rotation center of the sample stage is adjusted to obtain a glancing angle. This adjustment does not need to be done very strictly and can be easily done by mechanical setting.

Thereby, the X-ray optical path connecting the X-ray source and the rotation center of the sample stage is uniquely determined.

Now, in short, this adjustment should be done so that the center of the divergence slit and the center of the X-ray detector (the center of the receiving slit attached to the X-ray detector) are located on this fixed X-ray optical path. However, this work can be done extremely easily as follows.

That is, first, the rotation angle of the sample stage and the rotation angle of the X-ray detector are both set to 0, and then a slit whose center is the rotation center of the sample stage is placed on the sample stage, and the rotation angle of the X-ray detector is set to 0. While measuring with the X-ray detection section so that the center of the X-ray flux to be regulated coincides with the center of the X-ray detection section, the sample stage and the X-ray detection section are integrated and rotated as a whole around their center of rotation. Adjust by rotating. This allows the X-ray source, the center of rotation and
Three points of the ray detection section are located on one X-ray optical path.

For the rest, set the center of the divergence slit to the
The width of the divergence slit may be narrowed down to a certain value or less, and the divergence slit is rotated about the rotation center while the intensity is measured by the Xm detection section. This allows for easy adjustment.

In addition, when computer control is performed, although the initial setting of each rotation angle of 0 degrees can be arbitrarily set, it becomes unnecessary to mechanically adjust the rotation angles of the sample stage and the X-ray detection section to 0 degrees, and Thereby, it is not necessary to make adjustments such that the sample stage and the X-ray detection section are integrated and rotated as a whole around their rotation center, and adjustment can be made by simply rotating only the X-ray detection section.

[Example] FIG. 1 is a diagram showing an example of an X-ray diffractometer according to the present invention.

This X-ray diffractometer supports the conventional divergence slit 7 shown in FIG. This is what I did.

Since the configuration other than this point is the same as that shown in FIG. 2, the same parts as in FIG. 2 are given the same reference numerals and redundant explanation will be omitted.

Now, in this embodiment, an arcuate trajectory 71 centered on point 0 is formed at an intermediate portion between the X-ray source 1 and point 0 on the goniometer main body 4; A support 72 is fitted so as to be slidable along.

This support 72 has a fitting portion with the arcuate track 71 having the same arc shape as the arcuate track 71, and therefore,
By moving this support along the circular arc trajectory, the divergence slit 7 supported by the support can be rotated about the rotation center 0.

Although not shown, the support 72 is connected to a pulse motor or other known drive source via a known transmission mechanism.

Next, the operation of the X-ray apparatus according to the above-described embodiment will be explained.

A powder sample S is placed on the sample stage 5, and while irradiating the sample S with X-rays from the X-ray source 1, the sample stage 5 and the X-ray detector 8 are rotated at a speed ratio of 1:2. At this time, the rotation angle (diffraction angle) of the X-ray detection section when the diffraction line from the sample S is detected by the X-ray detection section 8 is determined. The measurement data of the diffraction angle obtained in this way is processed into so-called AST.
By comparing the standard data of the M card and other known substances, it is possible to identify the sample S and obtain knowledge indicating the crystal lattice constant of the sample S and other properties of the sample.

Incidentally, the adjustment of the X-ray optical system in the above apparatus can be performed as follows.

First, the divergence slit 7 is removed from the X-ray optical path, and the relative positional relationship between the X-ray source 1 and the rotation center 0 of the sample stage 5 is adjusted to obtain a glancing angle. This adjustment does not need to be done very strictly and can be easily done by mechanical setting.

Thereby, the X-ray optical path connecting the X-ray source 1 and the rotation center O of the sample stage 5 is uniquely determined.

Next, adjustments are made so that the center d of the divergence slit 7 and the center of the X-ray detector 8 (the center r of the receiving slit 9 attached to the X-ray detector) are located on this fixed X-ray optical path. However, this work can be done very easily as follows.

That is, first, the rotation angle (θ) of the sample stage 5 and the rotation angle (2θ) of the X-ray detection section 8 are both set to 0, and then the rotation center 0 of the sample stage 5 is set to 0. A center adjustment slit (not shown) is arranged, and the X-ray detector 8 measures the center of rotation so that the center of the X-ray flux regulated by this slit coincides with the center r of the receiving slit 9. The adjustment is made by rotating the entire goniometer main body 4.

As a result, three of the X-ray source, rotation center, and X-ray detection section are
A point will be located on one X-ray optical path.

The rest may be done by positioning the center d of the divergence slit 7 on the X-ray optical path;
By narrowing the width of the divergence slit 7 to a certain value or less and measuring the intensity with the X-ray detection unit 8, the divergence slit 7 is rotated about the rotation center 0 by driving the drive device (not shown). Can be easily adjusted.

When using computer control, the rotation angles of θ and 2θ can be initially set to 0 degrees, so the rotation angles of the sample stage 5 and X-ray detection unit 8 can be mechanically adjusted to 0 degrees. This eliminates the need for
There is no need for adjustment by rotating the entire goniometer main body 4, and adjustment can be made by simply rotating only the X-ray detection section 8.

The above embodiment has the following advantages.

That is, the divergence slit 7 is θ, 2θ
By supporting it rotatably around the rotation center O,
The trial-and-error element as in the conventional example is completely eliminated, and
It has become possible to adjust the line optical system uniquely.

Additionally, this has made it easier to automate the process through computer control and the like.

Furthermore, in the case of computer control, there is no need to attach mechanical scales for θ and 2θ to the goniometer main body 4, and the zero point of each angle can be arbitrarily set inside the computer without attaching scales. . Therefore, if you set the zero point inside the computer without attaching a mechanical scale like this, it would be best to attach a jig such as an adjustment slit to the sample stage 5, and then While measuring the X-ray detection intensity with the means 8, the optical system can be adjusted by sequentially adjusting the rotation of the X-ray detection means 8 and the divergence slit 7 individually, and there is no need to rotate the entire goniometer body 4. It disappears. Therefore, extremely large practical advantages can be obtained, such as eliminating the need for a controllably and mechanically difficult configuration for rotating the entire goniometer main body 4.

In the above embodiment, in order to rotate the divergence slin door around point 0, an arcuate trajectory 71 centered on point O is provided on the goniometer main body 4 at an intermediate portion between the X-ray source 1 and point O. This arcuate trajectory 71
1, and the divergence slit 7 is supported on this support 72. This is, for example, an arm rotatable about the point 0. The divergence slit may be supported on this arm, and in short, any known mechanism for rotatably supporting the divergence slit around point 0 is included.

[Effects] As described in detail above, the present invention has a configuration in which the divergence slit is rotatably supported around the rotation center of the sample stage, thereby significantly facilitating the adjustment of the X-ray optical system, and making the device easier to adjust. This has the excellent effect of making it possible to simplify and automate the process.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present invention, and FIG. 2 is a diagram showing a conventional example of the present invention. DESCRIPTION OF SYMBOLS 1... X-ray source, λ... Goniometer, 3... Base, 4... Goniometer main body, 5... Sample stage,
6... 2θ rotation section, 7... Divergence slit, 8... X-ray detection section, 9... Receiving slit. Applicant: Munk Science Co., Ltd.

Claims (1)

[Claims] An X-ray source, a divergence slit that regulates the divergence angle of X-rays emitted from the X-ray source, and a system that directs the X-rays that have passed through the divergence slit to a specific surface of a crystalline sample. a sample stage rotatably supporting the sample so that the sample can be incident at various angles; In an X-ray diffractometer, the X-ray diffractometer includes an X-ray detection means rotatably supported in a certain relationship with the rotation angle of the sample around the rotation center of the sample, the divergence slit being set at the rotation center of the sample. An X-ray diffractometer characterized by being rotatably supported around a center.