WO2006022333A1

WO2006022333A1 - Curvature distribution crystal lens, x-ray device having curvature distribution crystal lens, and curvature distribution crystal lens manufacturing method

Info

Publication number: WO2006022333A1
Application number: PCT/JP2005/015442
Authority: WO
Inventors: Kazuo Nakajima; Hiroshi Okuda; Kozo Fujiwara
Original assignee: Tohoku University; Kyoto University
Priority date: 2004-08-27
Filing date: 2005-08-25
Publication date: 2006-03-02
Also published as: JPWO2006022333A1; JP4710022B2

Abstract

[PROBLEMS] To provide a curvature distribution crystal lens used in a device performing a structure evaluation by diffraction of a material using X-rays and an analysis evaluation by spectrum and a curvature distribution crystal lens manufacturing method. [MEANS FOR SOLVING PROBLEMS] The curvature distribution crystal lens has a crystal plate of a high yield stress which has been plastically deformed and has a crystal lattice along the curved shape of the surface. The method for manufacturing the curvature distribution crystal lens is characterized in that a load is applied entirely or locally to the crystal plate of a high yield stress at a temperature below the melting point of the crystal so as to plastically deform the crystal plate to have a predetermined curvature.

Description

Specification

Curvature distribution crystal lens, X-ray apparatus having curvature distribution crystal lens, and method of manufacturing curvature distribution crystal lens

Technical field

TECHNICAL FIELD [0001] The present invention relates to an apparatus for structural evaluation by diffraction of a material using X-rays and analytical evaluation by spectroscopy, and in particular, a curvature distribution crystal lens, an X-ray apparatus having a curvature distribution crystal lens, and a curvature distribution crystal lens. The present invention relates to a manufacturing method.

Background art

[0002] In a conventional X-ray monochromator, the crystal is slightly bent slightly, and then polished so that a predetermined diffraction can be obtained uniformly by polishing, or conversely, the crystal is bent and deformed after polishing. Yes. X-ray Johann and Johansson monochromator crystals deformed within the elastic limit have been put into practical use. However, the conventional method for producing a monochromator crystal for X-rays deformed within this elastic limit cannot be bent with a large curvature, and therefore can only be used in a large X-ray apparatus. In addition, when it is allowed to greatly reduce angular resolution and integrated reflectivity, crystals with low yield stress were sometimes used after plastic deformation.

[0003] Since the monochromator crystal deformed within this elastic limit is limited in curvature and processing method, it should be used for compact devices and applications such as microbeam diffraction that require both high resolution and high brightness. I can't. In addition, KB mirrors used for microbeam generation in the sense of light concentrators require highly parallel and high-intensity light such as third-generation radiation for the source itself, and cannot be used in laboratory X-rays. It is. For small-angle scattering, parabolic mirrors (conferencing mirrors) and confocal mirrors are also manufactured for effective use of the source intensity. In addition, it is close to 10 million yen, and the capture angle does not reach 0.3 degrees. However, because there is no alternative technology, many of these mirrors are shipped domestically and overseas.

[0004] Johann type or Johansson type monochromators for X-rays are usually fixed by applying appropriate elastic deformation after cutting or polishing, or plastic deformation of crystals that are easy to process It is produced by the method. However, the method using elastic deformation has a problem of secular change in the amount of deformation in holding an elastically deformed crystal, and the deformation is within the elastic limit, so the prospective angle is limited to a very small value. In addition, when plastic deformation is used, problems such as a significant increase tl in the inverse value accompanying crystallinity deterioration due to plastic deformation and a decrease in integrated reflectivity occur. For this reason, the development of a method for producing a spectroscopic lens capable of obtaining a large prospective angle, that is, condensing efficiency without degrading the optical performance has been desired.

[0005] There is a strong demand for an X-ray diffractometer that has been downsized so that it can be used widely and universally. The obstacles are that X-ray Johann and Johansson monochromator crystals can only be produced within the elastic limit, so that the radius of curvature cannot be reduced and precision machining by polishing is required. In the point.

[0006] Patent Document 1: Japanese Patent Laid-Open No. 6-160600 @ @

Patent Document 2: Japanese Patent Laid-Open No. 2003-014895

Disclosure of the invention

Problems to be solved by the invention

[0007] Therefore, the present invention solves these difficulties, and curvature distribution crystal lenses such as Johann type and Johansson type for X-rays whose crystal plane has an arbitrary two-dimensional curvature distribution, such as a condensing type monochrome. It is an object of the present invention to provide a technique capable of freely producing a meter crystal. Means for solving the problem

In order to solve the above-mentioned problems, the present invention applies a load to a crystal plate having a high yield stress entirely or locally at a temperature below the melting point of the crystal, particularly at a temperature near the melting point, The present invention provides a method for producing a curvature distribution crystal lens, which is molded so as to have a predetermined curvature by plastic deformation.

The temperature below the melting point of the crystal in the present invention is the heating temperature from the temperature at which plastic deformation of the crystal plate starts to just before the temperature at which partial melting starts at the time of pressurization !, and the temperature near the melting point of the crystal in the present invention. The heating temperature from a temperature at which a complete curvature distribution crystal lens having a predetermined curvature can be produced to a temperature immediately before partial melting starts at the time of pressurization.

[0009] The present invention also provides a high yield stress at a temperature below the melting point of the crystal, particularly at a temperature near the melting point. A crystal lens molded to have a predetermined curvature is applied by applying an overall or local load to the crystal plate and plastically deforming the crystal plate, and at the same time as a predetermined curved surface distribution, secondary polishing is performed. The present invention provides a method for producing a curvature distribution crystal lens, which is characterized by being molded so as to have a curved surface.

Furthermore, the present invention provides the following as a curvature distribution crystal lens manufactured by the method of manufacturing a curvature distribution crystal lens.

(1) A crystal lens obtained by plastic deformation of a crystal plate having a high yield stress, and a curvature distribution crystal lens having a crystal lattice along a curved surface shape.

(2) A crystal lens obtained by plastic deformation of a high yield stress crystal plate, having a crystal lattice along a curved surface shape and having a quadratic curved surface.

(3) As a material of the crystal plate, a compound semiconductor such as Si, Ge, SiGe, and GaAs, an oxide such as MgO, Al 2 O, or SiO, or a halide such as LiF or NaCl is used.

2 3 2

Curvature distribution crystal lens using crystals.

(4) The crystal plate has on its surface one or two of compound semiconductors such as Si, Ge, SiGe, and GaAs, oxides such as MgO, Al 2 O, and SiO, and halides such as LiF and NaCl. Less than

2 3 2

Curvature distribution crystal lens, which is a thin film crystal deposited from above.

(5) Monochromator curvature distribution crystal lens used in the X-ray apparatus realized by the curvature distribution crystal lens.

Furthermore, the present invention provides an X-ray apparatus constituted by an optical component including an X-ray source and a curvature distribution monochromator crystal lens.

Here, the X-ray apparatus is an X-ray apparatus using X-rays as described in the section of the best mode for carrying out the invention (a) to (g)! Uh.

The invention's effect

[0012] According to the present invention, the following effects can be obtained.

When using a crystal having a high yield stress such as Si, a single crystal or multicrystal of a butter shape is usually cut into a plate-like wafer crystal and subjected to various processing. This is because the crystal was believed to be hard and brittle and cannot be bent, so the idea of using a wafer crystal with curvature was strong. In the present invention, a crystal is formed using a high temperature pressurization method. Since the plate is plastic processed into a lens shape, and a crystal lens with a crystal lattice along the curved surface shape can be molded into any curvature, shape, and size, it is a compact size that requires almost no abrasive molding.

X-ray curvature distribution crystal lens' monochromator can be manufactured. In addition, it is possible to obtain a spectroscopic lens that can obtain a large prospective angle, that is, light collection efficiency without degrading optical performance.

This makes it possible to realize a compact X-ray diffractometer, especially as a crystal material, compound semiconductor crystals such as Si, Ge, Si Ge, and GaAs, oxides such as MgO, Al 2 O, and SiO, LiF, N

2 3 2

By using a crystal made of a halide such as aCl, the optimum diffraction conditions, crystal plane and crystal plane orientation can be arbitrarily selected. In terms of cost, since processing and molding are simple, it is significantly more advantageous in terms of multi-product productivity in terms of reproducibility, optical performance, and spectral performance than conventional technologies.

Furthermore, by using the crystal lens and the monochromator of the present invention, X-ray irradiation of the same size as the light source size (several microns to several tens of microns) is lost due to slits or the like due to the effect of two-dimensional focusing. The efficiency is improved by up to 2 digits compared to the conventional one.

In the case of one-dimensional focusing (cylindrical Johansson, cylindrical Johan), and diffraction applications such as powder diffraction, the efficiency is lower than that of two-dimensional focusing. As a result, more powerful experiments are possible. In this case as well, the strength can be expected to increase by an order of magnitude compared to the normal slit system. Furthermore, when compared with conventional optical systems using curved multilayer mirrors, X-ray focusing is overwhelmingly advantageous in terms of price and performance due to ease of fabrication and maximum capture angle (up to about 10 times). An optical system can be realized.

Brief Description of Drawings

[0014] [Fig. 1] An example of actual measurement of crystal plane distribution of a spherical crystal monochromator.

[Fig. 2] This is an example of application to a two-dimensional Johansson focused diffraction crystal with a symmetric (a) and asymmetric (b) arrangement.

FIG. 3 is a configuration example of a sample position focusing type fluorescence analyzer and a sample position focusing type diffractometer using the spherical crystal monochromator of FIG.

FIG. 4 is a diagram showing a high-position resolution diffractometer of a two-dimensional focusing concentration type. FIG. 5 is a diagram showing a concentrating single crystal analyzer and the relationship between a sample and a detector.

FIG. 6 is a diagram showing a high-intensity diffuse scattering measurement apparatus.

FIG. 7 is a diagram showing a high intensity diffractometer using a linear beam.

FIG. 8 is a diagram showing a high magnification X-ray microscope apparatus having a configuration of a micro focus X-ray generator, a high-precision two-dimensional focusing monochromator, and a slit system.

FIG. 9 is a diagram showing a configuration example of a normal diffraction type point-focus X-ray generator, an asymmetric cut crystal, and a scattering diffraction measurement apparatus using a cylindrical Johansson.

FIG. 10 is a view showing upper and lower boats that process a Si (100) single crystal plate into a hemispherical shape.

FIG. 11 is a photograph of a hemispherical Si single crystal plate.

FIG. 12 is a diagram showing the result of a pressurization test in which the thickness of the crystal plate and the temperature during pressurization are shown as parameters.

FIG. 13 is a photograph of a Si (111) single crystal curvature distribution crystal lens.

BEST MODE FOR CARRYING OUT THE INVENTION

[0015] FIG. 10 shows the upper and lower boats where the Si (100) single crystal, which is a high yield stress crystal, is hemispherically covered. This upper and lower boat consists of two upper and lower carbon boats, a hemispherical depression (concave) is formed in the lower boat, and a hemispherical depression that fits in the upper boat just with a little margin in the lower boat. A protrusion (convex) is formed.

Next, a method for producing a hemispherical Si single crystal plate using these boats will be described. A release material is applied to the lower surface of the upper boat and the upper surface of the lower boat, and annealed at a high temperature. After that, a Si single crystal plate was sandwiched between the upper and lower boats that had been treated and placed in a vertical furnace. In order to prevent contamination and heat-induced surface deterioration on the entire surface or a part of the Si single crystal plate, a surface protective film that is resistant to heat, such as a mold release agent, and has few impurities may be applied. In this vertical furnace, a metal push rod is arranged at the top of the furnace, and by controlling this push rod from the outside, compressive stress (load) is applied to the upper surface of this carbon upper boat. The necessary force can be applied to the Si single crystal plate.

[0017] The upper boat, the lower boat and the Si single crystal plate set in this manner are heated to an appropriate temperature close to the melting point of Si in a hydrogen atmosphere. When this appropriate temperature is reached, the metal rod is It was lowered in the furnace and a 200N load was applied by pushing the upper surface of the upper boat. As a result, compressive force is also applied to the Si single crystal plate, and deformation between the hemispherical upper and lower boats by high-temperature pressurization results in a hemispherical Si single crystal plate. It was. The time during which the compressive force (load) was applied is between 0 and 1 minute. Thereafter, the furnace was rapidly cooled to prevent the processed Si single crystal plate from being modified by heat.

FIG. 11 shows a photograph of the hemispherical Si single crystal plate thus obtained.

[0018] FIG. 12 is a graph showing a combination of an upper boat having a hemispherical convex portion and a lower boat having a hemispherical concave portion when a compressive stress of 200 N is applied to a Si (100) single crystal plate. It is a figure which shows the result of the pressurization test which used the thickness of the board and the temperature at the time of pressurization as parameters. The horizontal axis is the thickness of the Si single crystal plate, and the vertical axis is the height of the plastically deformed hemispherical protrusion. In Fig. 12, ◯ indicates plastic deformation, △ indicates partly melted, and X indicates cracks that have broken.

It can be seen from the figure that the 0.33 mm thick crystal plate can be plastically deformed at 1120 ° C or higher, and the thicker crystal plate can be plastically deformed at 1200 ° C or higher. In addition, the height of the plastically deformed hemispherical convex portion increases as the temperature increases. It has been confirmed in another experiment that the numerical value of transition due to plastic deformation decreases as the temperature increases.

Looking further into the high-temperature region, the 0.33 mm thick crystal plate is completely 40 ° C lower, 1374 ° C and 30 ° C lower than 1414 ° C, the melting point of Si, and 1384 ° C. A hemispherical convex part is obtained. Above 1394 ° C, partial melting of the Si single crystal plate begins during pressurization.

From the above experimental results, the following can be said.

A curvature distribution crystal lens having a predetermined curvature is obtained by applying a load globally or locally to a high yield stress crystal plate such as Si at a temperature below the melting point of the crystal and plastically deforming the crystal plate. Can be produced. Furthermore, at a temperature near the melting point of the crystal, a complete curvature distribution with a predetermined curvature can be obtained by applying a load to the crystal plate of high yield stress such as Si entirely or locally and plastically deforming the crystal plate. Crystal lenses can be produced.

Here, the temperature below the melting point of the crystal is the temperature at which plastic deformation of the crystal plate begins (in the case of Si 11). The temperature near the melting point of the crystal is the heating temperature at which a complete hemispherical convex part is obtained, that is, a predetermined curvature. In the case of Si, in the case of Si, a heating temperature that is below the melting point of the crystal and a temperature force of 40 ° C or less. Wow!

The temperature at which this partial melting begins, the temperature at which plastic deformation begins, and the temperature near the melting point of the crystal differ depending on the crystal material to be processed.

[0020] A Si single crystal plate having a complete hemispherical convex portion is finished into a spherical Si crystal lens by polishing finishing, if necessary.

FIG. 1 is an actual measurement example of the crystal plane by X-ray of a spherical Si crystal lens (spherical crystal monochromator) having a radius of curvature of 50 mm manufactured by the manufacturing method of the present invention. Figure 1 shows the peak shift with respect to the lens center position. It can be seen that the value of Θ that gives a diffraction peak at a fixed 20 corresponding to the Si333 reflection is systematically shifted by the tilt of the crystal plane. In other words, here, reflecting the displacement from the center position, the crystal plane is inclined along the design sphere, and the Bragg peak position by the ω scan is shifted by an angle corresponding to the radius of curvature of the crystal. I am waking up.

[0021] The actual measurement result of the crystal plane distribution according to Fig. 1 shows that a high yield stress crystal plate is subjected to an overall or local load at a temperature below the melting point of the crystal, particularly at a temperature near the melting point, and the crystal plate is made plastic. Deformation means that a complete curvature distribution crystal lens having an arbitrary curvature distribution is formed.

In a crystal lens or monochromator using a high yield stress crystal obtained by a conventional method, the crystal lattice is a force that is not bent along the curved surface shape of the surface. Since the Si single crystal lens constituting the hemispherical convex part is plastically deformed without distortion of the crystal lattice, a curvature distribution crystal lens having a crystal lattice along the curved surface shape of the surface can be obtained.

[0022] In addition to a curvature distribution crystal lens using Si (lOO) single crystal, a curvature distribution crystal lens using other surfaces such as a Si (lll) single crystal can be produced in the same manner.

FIG. 13 shows a photograph of the curvature distribution crystal lens. The one in the figure is a crystal of Si (lll) plane Obtained.

It goes without saying that a curvature distribution crystal lens having a hemispherical or other arbitrary curvature can be produced by changing the shape of the irregularities of the upper and lower boats. Furthermore, the molded crystal lens can be polished and molded to have a predetermined curved surface distribution and a secondary curved surface by polishing.

In addition to Si, the material of the crystal plate can be any one of compound semiconductors such as Ge, SiGe, and GaAs, oxides such as MgO, Al 2 O, and SiO, and halides such as LiF and NaCl.

2 3 2

It can produce similarly using the crystal | crystallization which becomes.

Furthermore, on the crystal plate surface, compound semiconductors such as Si, Ge, SiGe, GaAs, MgO, Al 2 O 3

2

From one or more of oxides such as SiO, halides such as LiF, NaCl, etc.

3 2

The same thin film crystal can be produced using a deposited crystal plate.

[0024] Applications of the curvature distribution crystal lens according to the present invention are widespread such as compact high-precision or high-intensity X-ray diffraction apparatus, high-intensity scanning microbeam X-ray diffraction / fluorescence microscope apparatus.

It can also be applied to angle-resolved spectroscopic crystal lenses of aspherical types such as pseudo-cylindrical surfaces, ellipsoidal surfaces, and paraboloids.

Next, an application example of the curvature distribution crystal lens according to the present invention to an X-ray apparatus will be introduced below.

(a) Sample position-focusing fluorescence Z-diffraction analyzer using a two-dimensional condensing monochromator As shown in Figure 2, it has a Johansson type monochromatic shape in plane ABC with respect to light source position A and condensing position B. For the z direction of 2, a monochromator function that separates only characteristic X-rays from an X-ray generator with a point source as shown in Fig. 3 by creating a curved crystal with a curvature of radius H In addition, it is possible to collect light up to the same size as the X-ray generation light source size at the same time as capturing at a large solid angle. There are (100), (111) and (110) plane crystals such as semiconductor crystals such as Si, Ge, and GaAs as crystals, and single crystals with off-angles of these forces corresponding to asymmetrical arrangements are available. Force For example, when Ge (l 11) crystal is used, the 333 diffraction line 2 Θ is about 90 degrees with respect to the CuKa characteristic X-ray, and a configuration that can be easily adjusted can be made. In addition, 111 and 220 reflections are used when priority is given to efficiency. The fluorescence excited by this condensed X-ray is converted into an energy-resolved detector (such as SSD). ). X-rays can be analyzed by irradiating microscopic areas with strong excitation X-rays without cutting them off by pinhole slits, regardless of the solid 'liquid' environment. In addition, as shown in the figure, an analytical crystal is placed after the sample, and an independent slit is inserted in the y and z directions before monochrome, so that it functions as a micro-area diffractometer with low angular resolution. It can also be used as a wavelength dispersive fluorescence analyzer by fixing the sample and scanning the 2 Θ arm analysis condensing crystal with a 0–20 relationship with respect to the detector.

[0026] (b) High-efficiency, high-position resolution diffractometer using two-dimensional focusing crystal and spectral crystal

As shown in Fig. 4, the relative relationship between the X-ray light source and the sample position is set. This is a configuration that combines a Guinier camera and a concentration method, and is a configuration in which resolution is prioritized over a small region of X-rays at the sample position. The X-rays collected in the previous stage pass through the slit as a point light source through slit 1, and this position becomes the X-ray focal position in the concentration method, and measurement is performed using the sample that satisfies the concentration condition and the detector slit position. .

[0027] (c) Single-crystal diffractometer using two-dimensional focusing crystal and area detector

Same as (a) in that a 2D curved crystal that satisfies the point convergence condition for a point light source is used. The focal plane of the force crystal is placed at the detector position, and simultaneous measurement is performed using a 1D or 2D detector. .

Figure 5 shows an outline of the configuration. As crystal measurement modes, normal single crystal analysis, Weisenberg camera mode, etc. are possible depending on the crystal rotation and detector exposure synchronization conditions. The angular resolution at the focal plane is arbitrarily changed by inserting a variable slit between the light source and the crystal or between the crystal and the sample. Another feature is that by placing the detector on the focal surface, no angular error is produced on the detector in principle, no matter how large the capture angle is used.

[0028] (d) High-intensity diffuse scattering measurement device with arbitrary angular resolution by a two-dimensional focusing crystal

The point that the slit and the spectral Z condensing crystal are inserted into the light source and the focal plane is the detector surface is the same as (c), but the detector surface is positioned relative to the sample position as shown in Fig. 6. High-efficiency measurement for small-angle scattering and diffuse scattering analysis, characterized by long-distance or focal-surface placement, which does not degrade the angular resolution of the scattering intensity measurement while increasing the light collection angle. Is possible. [0029] (e) High-intensity diffractometer using one-dimensional focusing crystal

A high-intensity diffractometer can be constructed by placing a cylindrical Johansson monochrome in a symmetrical or asymmetrical arrangement with respect to a linear X-ray source. Fig. 7 (a) shows an example of the high-intensity diffractometer, and a configuration in which the luminance is further increased by inserting an asymmetric crystal in the z direction in the figure (Fig. 7 (b)) is also possible. It can be used as a concentrating X-ray device using a cylindrically selected crystal without polishing as a simple arrangement. This cylindrical crystal can also be used as a fluorescent X-ray spectroscopic crystal.

[0030] (f) High magnification X-ray microscope apparatus using a two-dimensional focusing monochromator

A high-magnification X-ray microscope is realized by arranging a two-dimensional condensing monochromator as shown in Fig. 8 for the micro-focus X-ray generator and placing a stop on the focal plane.

[0031] (g) Scattering diffraction measurement device using high brightness optimizing of finite-width point light source

As shown in Fig. 9, a point light source with a certain width is narrowed in one direction depending on the expected angle. By shining, it produces X-rays that are almost ideally bright at the focal point.

The small angle scattering device is installed between the focal plane and the crystal as in the case of (d). Compared to a two-dimensional condensing optical system, the condensing efficiency is slightly worse, but it has the advantage that a high-power X-ray generator can be used and the angle resolution can be easily improved.

Claims

The scope of the claims

[1] A crystal lens obtained by plastic deformation of a crystal plate having a high yield stress, which has a crystal lattice along a curved surface shape.

[2] A crystal lens obtained by plastic deformation of a crystal plate having a high yield stress, having a crystal lattice along a curved surface shape and having a quadratic curved surface.

[3] As the material of the crystal plate, a crystal composed of any one of compound semiconductors such as Si, Ge, SiGe, and GaAs, oxides such as MgO, Al 2 O, and SiO, and halides such as LiF and NaCl.

2 3 2

The curvature distribution crystal lens according to claim 1, wherein:

[4] The above crystal plate has a compound semiconductor such as Si, Ge, SiGe, GaAs, MgO, Al on its surface.

One or more of oxides of oxides such as O and SiO, and halides such as LiF and NaCl

2 3 2

4. The curvature distribution crystal lens according to claim 3, wherein a thin film crystal is deposited.

5. The curvature distribution crystal lens according to any one of claims 1 to 4, wherein the curvature distribution crystal lens is a curvature distribution monochromator crystal lens used in an X-ray apparatus.

[6] An X-ray apparatus comprising an X-ray source and an optical component including the curvature distribution monochromator crystal lens according to claim 5.

[7] A high yield stress crystal plate is subjected to a total or local load at a temperature below the melting point of the crystal, and the crystal plate is plastically deformed to have a predetermined curvature. A method of manufacturing a characteristic curvature crystal lens.

[8] A characteristic is that a high yield stress crystal plate is subjected to a load globally or locally at a temperature near the melting point of the crystal, and the crystal plate is plastically deformed to have a predetermined curvature. A method of manufacturing a curvature distribution crystal lens.

[9] A crystal lens molded to have a predetermined curvature by applying a load to a high yield stress crystal plate entirely or locally at a temperature below the melting point of the crystal and plastically deforming the crystal plate. A method for producing a curvature distribution crystal lens, characterized in that a lens is molded so as to have a predetermined curved surface distribution and a secondary curved surface by polishing.

[10] A crystal formed so as to have a predetermined curvature by applying a load to a crystal plate having a high yield stress entirely or locally at a temperature near the melting point of the crystal and plastically deforming the crystal plate. A method for producing a curvature distribution crystal lens, characterized in that a lens is polished and molded so as to have a predetermined curved surface distribution and a secondary curved surface by polishing.