JP3529068B2 - X-ray small angle scattering device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray small angle scattering device for measuring a change in the intensity of scattered X-rays in a small angle region centered on the optical axis of incident X-rays.

[0002]

2. Description of the Related Art Depending on a substance, scattered X-rays may be generated in a small angle region around the optical axis of the incident X-ray, for example, an angle region of about 0 ° to 5 ° when the substance is irradiated with X-rays. is there. For example, when fine particles of about 10 to 1000 Å or a non-uniform region having a density corresponding to this exist in the substance, diffuse scattering in the incident line direction, so-called central scattering occurs. This central scattering is irrelevant to the internal structure of the particle and spreads as the particle becomes smaller. This scattering exists regardless of whether it is crystalline or amorphous, and the scattering angle, that is, the incident X
It is observed in a small angle region where the angle from the optical axis of the line is about 0 ° to 5 °. In addition to the above central scattering in the small angle region, Bragg reflection when the lattice spacing is very large like a protein crystal, and crystalline and amorphous are periodically arranged in a fiber sample. , X-ray diffraction and the like in the case of so-called long-period structure are observed. The X-rays observed in the small angle region, including the central scattering, Bragg reflection and X-ray diffraction as described above, are generally called small angle scattering.

The X-ray small angle scattering apparatus according to the present invention is an apparatus for measuring such small angle scattering. Since this X-ray small-angle scattering device measures weak scattered X-rays generated from the sample, it is necessary to eliminate as much as possible parasitic scattering that lowers the resolution and the S / N ratio. Here, the resolution is
The small angle resolution, which indicates how small the scattered X-rays can be measured, and the angular resolution required to measure adjacent diffracted rays separately, are considered to be high. Needs to be done. Parasitic scattering is X-rays observed when a sample is removed from the X-ray measurement system, and is excited by diffused scattering from optical elements exposed to scattered X-rays or white X-rays. It is considered that fluorescent X-rays and the like are the main causes.

In order to realize the above-mentioned measurement with high accuracy, various types of small-angle X-ray scattering devices have been conventionally known. For example, as shown in FIG. 4, the first slit 5
A so-called three-slit system small-angle X-ray scattering device using three slits, that is, a first slit 52, a second slit 52, and a third slit 53 is known. In this X-ray small angle scattering device, the radiation source F
The X-rays radiated from and diverging are shaped into a parallel X-ray beam using the first slit 51 and the second slit 52, and the progress of parasitic scattered X-rays generated in the second slit 52 is blocked by the third slit 53. Then, the sample S is irradiated with X-rays excluding the parasitic scattered X-rays. When the sample S is irradiated with the parallel X-ray beam in this way, scattered X-rays are generated in a small angle region according to the property of the sample S, and the scattered X-rays expose the two-dimensional X-ray detector 54, An X-ray latent image corresponding to scattered X-rays is formed on the X-ray detector 54. After visualizing this X-ray latent image, the internal structure of the sample S is determined by observing the visible image.

[0005]

A conventional three-slit system X
In the small line angle scattering device, each of the first slit 51, the second slit 52, and the third slit 53 has an individual holder 5.
5 and the sample S was also supported by a dedicated sample holder 56. Further, as shown in FIG. 5, the first slit 51, the second slit 52, and the third slit 53 are integrally supported by one holder 57,
There is also known an X-ray small angle scattering device in which the sample S is supported by a dedicated sample holder 56.

By the way, in FIG. 4, the X-ray detector 54
Reference numeral D shown in FIG. 2 is a region where the X-ray emitted from the radiation source F passes through the sample S and is directly received by the X-ray detector 54,
The irradiation area of a so-called direct beam is shown. The symbol E indicates a region where parasitic scattered X-rays generated at the second slit 52 reach the X-ray detector 54 without being blocked by the third slit 53. These areas D and E are areas in which the scattered X-rays to be measured, which are generated from the sample S, cannot be read due to the influences of the direct beams and the parasitic scattered X-rays from the second slit 52, so-called non-measurement. It is a feasible area.

In the conventional small-angle X-ray scattering device, the mechanical size of the sample holder 56 and the slit holder 55 (FIG. 4) or the mechanical size of the sample holder 56 and the slit holder 57 (FIG. 5). Third because of its size
The distance L4 between the slit 53 and the sample S could not be reduced. Specifically, it could be only about 20 mm at the shortest. The fact that the distance L4 cannot be shortened means that the area E of the parasitic scattered X-rays that reach the X-ray detector 54 through the third slit 53 cannot be narrowed, which means that the X-ray detection is performed. This means that the unmeasurable region in the instrument 54 becomes wider and the wider region of the X-ray detector 54 cannot be observed.

Further, in the conventional small-angle X-ray scattering device, the sample holder 56 and the slit holder 55 or 57 are separate bodies as described above, so that the sample S is adjusted when the optical positional relationship of the entire device is adjusted. The positional relationship between the third slit and the third slit had to be adjusted individually, and the task of adjusting the positional relationship was extremely troublesome. The present invention has been made to solve the above-mentioned problems in the conventional apparatus, and widens the measurable area in the X-ray detector and facilitates the optical position adjustment of the third slit and the sample. The purpose is to

[0009]

In order to achieve the above object, an X-ray small-angle scattering apparatus according to the present invention comprises a first slit and a first slit for shaping an X-ray emitted from an X-ray source into a parallel X-ray beam. An X having two slits, a third slit that guides a parallel X-ray beam to the sample while blocking the progress of scattered X-rays generated by the second slit, and an X-ray detector that detects scattered X-rays generated from the sample In the small line angle scattering device, the third slit and the sample are integrally supported by the same supporting member.

If the third slit and the sample are supported by the same support member, the distance between the third slit and the sample can be made very small. This means that the distance between the second slit and the third slit can be increased when the distance between the second slit arranged on the upstream side of the third slit and the sample is kept constant. is there. The fact that the distance between the second slit and the third slit can be increased in this way narrows the region where parasitic scattered X-rays generated from the second slit reach the X-ray detector after passing through the third slit. As a result, it is possible to widen the region where the scattered X-rays, which are the measurement targets generated from the sample, can be captured by the X-ray detector toward the low angle side. Further, if the third slit and the sample are integrally supported by the same support member, the position of both the third slit and the sample can be adjusted by only adjusting the position of one of the support members when optically adjusting them. Can be executed at the same time, improving operability.

As a concrete structure for integrally supporting the third slit and the sample by the same supporting member, for example, a sample stopper is provided on a slit plate having the third slit, and the sample is fixed by the sample stopper. A configuration of supporting is conceivable. The sample stopper may be, for example, a leaf spring or other spring member that presses the sample against the slit plate by a spring force, an adhesive, or an adhesive tape. The slit shape of the third slit may be a round hole or an elongated hole.

[0012]

1 shows an embodiment of an X-ray small angle scattering device according to the present invention. This X-ray small angle scattering device is a slit unit 9 including a radiation source F that generates X-rays, and a first slit 1 and a second slit 2.
And a third slit 3 arranged on the downstream side (right side in the drawing) of the slit unit 9, and an X-ray detector 4 arranged on the downstream side of the third slit 3. In this embodiment, an X-ray detector capable of capturing X-rays in a plane, that is, a two-dimensional X-ray detector is used as the X-ray detector 4. As the two-dimensional X-ray detector, for example, a stimulable phosphor or an X-ray film can be considered.

The X-ray film is a flat film which can be exposed to X-rays to form a latent image on that portion and which can be visualized by a developing process. By visually observing this visible image, it is possible to measure the incident position and the intensity of the X-ray that has contributed to the exposure of the X-ray film.

On the other hand, the stimulable phosphor is a substance which is also called a stimulable phosphor and is a flat photosensitive member for X-rays and the like. This stimulable phosphor is a substance that has the property of being capable of accumulating X-rays and the like in the form of energy, and of being able to extract that energy as light by irradiation with stimulated excitation light such as laser light. is there. That is, when the stimulable phosphor is irradiated with radiation such as X-rays, energy is accumulated as a latent image in the stimulable phosphor corresponding to the irradiated portion, and the stimulable phosphor is further stimulated by laser light. When the excitation light is irradiated, the latent image energy becomes light and is emitted to the outside. By detecting the emitted light with a photoelectric tube or the like, it is possible to measure the X-rays that contributed to the formation of the latent image, in the case of the present invention, the scattering angle and the intensity of the scattered X-rays from the sample.

In this embodiment, in FIG. 1, the first slit 1 is supported by a dedicated slit supporting member 5a, the second slit 2 is supported by a dedicated slit supporting member 5b, and the third slit 3 and the sample are supported. S is integrally supported by a common support member 7. As shown in FIG. 2, the support member 7 is configured by providing a sample stopper 12 on a slit plate 11 having a round hole-shaped third slit 3 formed therein. In the case of the present embodiment, the sample stopper 12 is configured by fixing the outer ends of the leaf springs to the surface of the slit plate 11 and making their inner ends the free moving ends. The sample S is a leaf spring-shaped sample stopper 12
It is placed at the downstream side position of the third slit 3 of the slit plate 11 by being sandwiched between the free moving ends of the slit plate 11.

The slit plate 11 supporting the sample S is supported by the sample support stage 8 fixedly installed at a predetermined position of the X-ray small angle scattering device. This sample support stage 8
Is a pair of support blocks 13 and 13 that support the slit plate 11 without rattling, a Z stage 14 that supports the support blocks so that they can move in parallel in the vertical direction, and the Z stage thereof.
It has an XY stage 15 that supports the stage 14 so as to be movable in parallel in the front, rear, left, and right planes.

Since the X-ray small-angle scattering device of this embodiment is configured as described above, the X-rays emitted from the radiation source F and diverged from the first slit 1 and the second slit 2 in FIG. The slit unit 9 is formed into a parallel X-ray beam, and the parallel X-ray beam is incident on the sample S. Then, scattered X-rays are generated from the sample S according to the properties of the sample 2, the scattered X-rays reach the X-ray detector 4 and are exposed to the light, and a latent image is formed on the exposed portion. By reading this latent image, the scattering angle of scattered X-rays (that is, the angle 2θ from the X-ray optical axis L) and the X-ray intensity can be measured.

During this measurement, the second slit 2 produces parasitic scattered X-rays when the X-rays strike it. This parasitic scattering X
Since the X-ray becomes a noise component for the scattered X-ray from the sample S to be measured, the parasitic scattered X-ray should reach the X-ray detector 4 as much as possible. The third slit 3 blocks the parasitic scattered X-rays from going to the X-ray detector 4. Specifically, the parasitic scattered X-rays are prevented from leaking to the area G outside the area E ′ defined by the broken line L1 connecting the second slit 2 and the third slit 3. In other words, the area E ′ is an area that is exposed to the direct beam or the parasitic scattered X-rays and cannot be measured, while the area G is normal without receiving the direct beam or the parasitic scattered X-rays. This is an area where measurements can be made.

The XY stage 15 and the Z stage 14 shown in FIG.
The operator manually or automatically controls the translation by an appropriate distance.

By the way, in the conventional apparatus shown in FIGS. 4 and 5, the holder 55 or 5 for supporting the third slit 53 is used.
Since 7 and the sample holder 56 were separate, the distance L4 between the third slit 53 and the sample S could not be reduced due to the mechanical size of those holders. Therefore, in the case of the conventional apparatus, when the distance between the second slit 52 and the sample S is kept constant, the second slit 2 and the third slit
The distance L3 to the slit is inevitably small, and as a result, the parasitic scattering X generated in the second slit 2 occurs.
The area E where the ray reaches the X-ray detector 54 was quite large.

On the other hand, in the X-ray small angle scattering device according to the present embodiment, as shown in FIG. 1, the third slit 3 and the sample S are integrally supported, so that the third slit 3 and the sample S are integrated.
The distance L4 ′ between the second slit 3 and the third slit 3 can be made very small, and as a result, the distance L4 between the second slit 3 and the third slit 3 can be reduced.
You can take a big 3 '. As a result, the region where the parasitic scattered X-rays from the second slit 2 can reach the X-ray detector 4 can be made extremely smaller than the conventional region E, as indicated by the reference symbol E ′. Therefore, it is possible to increase the area that can be used for observation, that is, the measurable area G.

Further, by integrally supporting the third slit 3 and the sample S, their optical positions can be determined by the radiation source F.
When adjusting to an appropriate position with respect to, the adjustment operation becomes very simple.

In the embodiment shown in FIG. 2, a round hole-shaped slit is used as the third slit 3. However, as shown in FIG. 3, the third slit 3 may be formed of an elongated hole-shaped slit. . Furthermore, it is also possible to use a square slit.

Although the present invention has been described with reference to the preferred embodiments, the present invention is not limited to the embodiments and can be variously modified within the technical scope described in the claims. For example, the sample stopper 12 shown in FIG. 2 is not limited to the structure using a leaf spring, but may be a structure using an adhesive, an adhesive tape, or the like. Also, the slit plate 1
As the structure for supporting 1 as well, any structure other than the structure using the support block 13 as shown in FIG. 2 can be adopted. Further, in the embodiment of FIG. 1, the first slit 1 and the second slit 2 are supported by the respective support members 5a and 5b, but they may be supported by the common support member. Further, in the embodiment of FIG. 1, a two-dimensional X-ray detector is used as the X-ray detector, but instead of this, a one-dimensional X-ray detector such as a scintillation counter, that is, a format for detecting X-rays at one point. X-ray detectors can also be used. However, when using this one-dimensional X-ray detector, it is necessary to detect scattered X-rays from the sample while rotating and moving the one-dimensional X-ray detector around the sample.

[0025]

According to the X-ray small angle scattering device of the first aspect, since the third slit and the sample are integrally supported by the same support member, the space between the second slit and the third slit is increased. The distance can be increased, resulting in X
The measurable region of scattered X-rays from the sample that can be measured by the ray detector could be expanded to the low angle side. Also, the third
By integrally supporting the slit and the sample, it has become possible to easily perform optical position adjustment of both the third slit and the sample.

According to the X-ray small angle scattering device of the second aspect, the integral structure of the third slit and the sample can be constructed very easily. Further, the distance between the third slit and the sample can be made as small as possible.

According to the X-ray small-angle scattering apparatus of the third aspect, the sample can be attached to and detached from the third slit very easily.

[0028]

[Brief description of drawings]

FIG. 1 is a diagram schematically showing an embodiment of an X-ray small angle scattering device according to the present invention.

FIG. 2 is a perspective view specifically showing a main part of FIG.

FIG. 3 is a perspective view showing a modified example of a portion corresponding to FIG.

FIG. 4 is a diagram schematically showing an example of a conventional small-angle X-ray scattering device.

FIG. 5 is a diagram schematically showing another example of a conventional small-angle X-ray scattering device.

[Explanation of symbols]

1st slit 2 second slit 3rd slit 4 X-ray detector 5a, 5b Slit support member 7 Support member 8 Sample support stage 9 slit unit 11 slit plate 12 Sample stopper 13 Support block 14 Z stage 15 XY stage

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G01N 23/00-23/227

Claims (5)

(57) [Claims] 1. A first slit and a second slit for shaping an X-ray emitted from an X-ray source into a parallel X-ray beam, and a second slit.
Small-angle X-ray scattering having a third slit that guides a parallel X-ray beam to a sample while blocking the progress of parasitic scattered X-rays generated in the slit, and an X-ray detector that detects the scattered X-rays to be measured generated from the sample An X-ray small-angle scattering device, wherein the third slit and the sample are integrally supported by the same supporting member. 2. The X-ray small-angle scattering apparatus according to claim 1, wherein a sample stopper is provided on a slit plate having a third slit, and the sample is supported by the sample stopper. apparatus. 3. The X-ray small angle scattering device according to claim 2, wherein the sample stopper presses the sample against the slit plate by a spring force. 4. The X-ray small-angle scattering apparatus according to claims 1 to claim 3 Neu Zureka one 1, X-ray small-angle scattering and wherein the third slit is a round hole shape. 5. The X-ray small-angle scattering apparatus according to claims 1 to claim 3 Neu Zureka one 1, X-ray small-angle scattering and wherein the third slit is elongated hole shape.