JP2001021782A - Method and device for supporting optical element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably support a diamond crystalline plate without bringing a grating face into an unstable condition by thermal shock even when a thermal load is applied by an X-ray. SOLUTION: When a diamond crystalline plate 4 irradiated with an X-ray is attached onto a base 1, an end face of the crystalline plate 4 is joined on an element fixing block 3 comprising a diamond single crystal, using the first joining material not fused by thermal load caused by the X-ray, and the element fixing block 3 is attached onto the base 1 by the second joining material not fused by the thermal load. Stable bonding, reduction of temperature gradient and suppression of thermal strain are thus attained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for stably supporting a diamond crystal, which is an optical element, in an optical device such as a diamond monochromator.

[0002]

2. Description of the Related Art For example, a position adjusting mechanism (goniometer)
Is a multi-station beam line called ESRF troika, which irradiates diamond crystals with high-brightness X-rays and obtains diffracted X-rays using the lattice plane. .

In a conventional diamond monochromator,
Both sides of the diamond crystal plate were mounted on the concave portion of the U-shaped copper cooling support base via In-Ga low-temperature solder.

[0004]

However, in the above conventional structure, the melting point of the In-Ga low-temperature solder is about 50 ° C., and when the diamond crystal plate is irradiated with high-brightness X-rays, the diamond crystal is heated. The low-temperature solder melts, and the surface tension holds the diamond crystal plate. Therefore, there is a problem that the position of the lattice plane of the diamond crystal becomes unstable due to fluctuation due to thermal shock.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems and provides an optical element which can stably support a diamond crystal plate without instability of a lattice plane due to thermal shock of irradiated X-rays and can suppress thermal deformation. It is an object to provide a supporting method and apparatus.

[0006]

According to a first aspect of the present invention, there is provided a method of supporting an optical element, comprising: mounting a diamond crystal plate to be irradiated with X-rays on a base;
An end face of the diamond crystal plate is bonded on the element fixing base with a first bonding material that is not melted by a thermal load by X-rays, and the element fixing table is mounted on a base with a second bonding material that is not melted by the thermal load. The diamond crystal plate, the element fixing base and the thermal expansion coefficient are approximated to each other, and the diamond crystal plate, the element fixing base and the base are made of a material having a good thermal conductivity.

[0007] The optical device support device according to the third aspect of the present invention is a device for supporting an optical element, comprising: a diamond crystal plate irradiated with X-rays;
An element fixing base interposed between the diamond crystal plate and the base, a first bonding material that is not melted by a thermal load by X-rays for bonding an end surface of the diamond crystal plate and the element fixing base, and an element fixing element; A second bonding material that is not melted by the thermal load for bonding the base and the base, and the thermal expansion coefficient is approximated with the diamond crystal plate and the element fixing base,
A material having good thermal conductivity is used for the diamond crystal plate, the element fixing base and the base.

According to each of the above structures, the bonding material at the bonding portion is not melted by the thermal load, so that the fixing of the crystal of the diamond crystal plate by the thermal shock does not become unstable. In addition, since the diamond crystal plate is attached to the element fixing base with a similar thermal expansion coefficient via its end face, deformation and distortion due to heat can be suppressed to a minimum, and the range of use that can be diffracted on the crystal surface is expanded. Can be. Further, since the heat of the diamond crystal plate loaded by X-rays can be transmitted well from the element fixing base to the base, heat can be dissipated effectively.

According to a second aspect of the present invention, there is provided a method for supporting an optical element according to the first aspect, wherein the element fixing base is formed of diamond, and a silver solder is provided on a joint surface between the diamond crystal plate and the element fixing base. After the attachment, the surface is coated with Ni, the diamond crystal plate and the element fixing base are soldered and joined with these first joining materials, and a silver brazing is brazed to the joint surface of the element fixing base to the base. After that, the surface is coated with Ni, and the element fixing stand and the base are soldered and joined with these second joining materials.

According to a fourth aspect of the present invention, in the configuration of the third aspect, the element fixing base is formed of diamond single crystal, and the first bonding material of the diamond crystal plate and the element fixing base is: A silver solder brazed to the bonding surface of the diamond crystal plate and the element fixing base,
A second thin film composed of the Ni thin film coated on the surface of the silver solder and the solder for joining the diamond crystal plate and the element fixing base via the silver solder and the Ni thin film, and The bonding material is a silver solder brazed to the bonding surface of the element fixing base, a Ni thin film coated on the surface of the silver solder, and a solder for joining the element fixing base and the base through the silver solder and the Ni thin film. It is composed of

According to each of the above constructions, the element fixing base is made of a diamond crystal, so that the coefficient of thermal expansion and the coefficient of thermal conductivity are made very close to each other, so that the deformation at the time of joining and the deformation at the time of heat load by X-ray irradiation can be effectively prevented. Can be suppressed. Also, the diamond crystals are brazed by silver brazing and N
Soldering can be performed by i-coating, and the diamond crystal plate and the element fixing base, and the element fixing base and the base can be satisfactorily joined.

According to a fifth aspect of the present invention, in the above structure, the cross-sectional area of the element fixing base is sufficiently large with respect to the cross-sectional area of the diamond crystal plate, and the bonding end face of the diamond crystal plate is formed. The bonding area of the element fixing base to the base is set to be sufficiently large with respect to the area, and the base is provided with cooling means. According to the above configuration, since the cross-sectional area of the element fixing base is formed large, X
The thermal gradient at the time of irradiation with rays can be reduced, and the heat transfer can be improved due to the large bonding area of the element fixing base to the base, so that the diamond crystal plate can be cooled effectively.

According to a sixth aspect of the present invention, in the above structure, the bonding surface to the diamond crystal plate and the bonding surface to the base of the element fixing base are formed parallel to each other. . According to the above configuration, it is possible to equalize the amount of deformation caused by the thermal expansion of the element fixing base due to the thermal load, and to reduce the influence on the diamond crystal plate.

Further, in the optical element supporting device according to the present invention, fine irregularities are formed on a bonding surface of each bonding portion between the diamond crystal plate and the element fixing base and between the element fixing base and the base. According to the above configuration, it is possible to increase the bonding strength between the crystal plate and the fixing base and the fixing base and the base by the brazing and the solder.

In the above structure, the opposing base may be disposed at a position symmetrical to the base of the diamond crystal plate, and the other end face of the diamond crystal plate may be subjected to heat load by X-rays. It is in contact with the opposing base via a heat transfer material that sometimes becomes molten.

According to the above configuration, the other end face of the diamond crystal plate is brought into contact with the opposing base by the heat transfer material, so that heat can be efficiently conducted to and released from the two bases, respectively. In addition, since the heat transfer material is configured to be melted at the time of heat load, the diamond crystal plate is not restrained at the joint of the opposing base and thermal deformation is absorbed. There is no thermal distortion of the plate.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Here, an embodiment of a supporting device for an optical element according to the present invention will be described with reference to FIGS. In FIG. 1, reference numeral 1 denotes a copper base provided with a diamond monochromator and having a high thermal conductivity capable of adjusting an inclined rotation posture and up / down / left / right positions by a position adjustment mechanism. A cooling channel 2 for water flow is formed in a direction orthogonal to the X-ray irradiation direction. On the base 1, an element fixing base 3 is joined via a joint 5B, and a diamond crystal plate 4 made of a diamond single crystal having a very low coefficient of thermal expansion and a high thermal conductivity is joined via a joint 5A. Is fixed. The diamond crystal plate 4 is, for example, a square of 8 mm square and 0.5 mm in thickness, and is configured such that an end face on a lower side thereof is joined to the element fixing base 3 to reduce thermal strain. A is the center position of the diamond crystal plate 4 (X = 0,
(Y = 0) shows an irradiation range where X-rays are irradiated.

The element fixing base 3 is made of the same diamond single crystal as the diamond crystal plate 4 or a diamond polycrystal similar thereto, or a diamond crystal having a very low coefficient of thermal expansion and a high thermal conductivity. A material similar to the plate 4 is selected and used. In addition, depending on the impurities and crystal direction included in the diamond crystal,
The thermal expansion coefficient and the thermal conductivity may be slightly different. This prevents the crystal of the diamond crystal plate 4 from being distorted by making the thermal expansion coefficients the same or similar.

The element fixing base 3 has a cross-sectional area (plane cross-sectional area) that is sufficiently larger than the cross-sectional area (plane cross-sectional area) of the diamond crystal plate 4, for example, a width of 8 mm and a depth of 3 mm.
mm × 2 mm in height, reduces the thermal gradient of the diamond crystal plate 4 during X-ray irradiation,
By increasing the bonding area to the base 1, heat conduction from the diamond crystal plate 4 to the base 1 can be improved. The bonding surface (upper surface) of the diamond crystal plate 4 and the bonding surface to the base 1 are formed parallel to each other, and the distortion of the diamond crystal plate 4 due to thermal expansion is equalized.

The diamond crystal plate 4 and the element fixing table 3
As shown in FIG. 2, for example, the thermal load of X-rays in this embodiment does not reach 220 ° C. at the junction 5A between Sn-Ag solder (melting point 220
° C) 6 is selected as the main material of the first and second joining materials.

In the joints 5A and 5B, the Sn-Ag solder 6 cannot directly join a diamond material. Therefore, silver brazing is applied to each joining surface between the diamond crystal plate 4 and the element fixing base 3. Ag-Cu-Ti) 7 is brazed, and the surface thereof is coated with a Ni thin film 8. The Ni thin film 8 is used for soldering with a Sn-Ag solder 6. Therefore, the silver solder 7, the Ni thin film 8, and the Sn-Ag solder 6 constitute a first bonding material and a second bonding material that are not melted by a heat load. Of course, the first bonding material and the second bonding material are changed depending on the materials of the diamond crystal plate 4, the element fixing base 3, and the base 1, and the thermal load of X-rays. Of course, it is needless to say that these bonding materials preferably have high thermal conductivity and low thermal expansion coefficient.

6 (a) and 6 (b), by forming an orderly uneven portion 9 on the order of several μm or several tens μm on one of the bonding surfaces of these bonding portions 5A and 5b. Improve the wettability of the solder 7 and the Sn-Ag solder 6 to get into the uneven portion 9 and join the tip of the uneven portion 9 and the diamond crystal plate 4 in contact with each other to improve the joining strength. Can be done. The fine uneven portion 9 may have a mountain shape as shown in FIGS. 6A and 6B or an uneven shape as shown in FIG. Further, the uneven portions 9 can be formed on both of the two joining surfaces.

Next, FIG. 3 shows a model of thermal deformation when a thermal load is applied to the diamond crystal plate 4 soldered to the base 1 via the element fixing stand 3 by X-ray irradiation. . As a result, the thermal deformation of the joint 5A side is large, but even the majority of the distortion is several tens nm or less, and the thermal distortion is extremely small at the center of the Y coordinate (height direction) = 0 where the X-ray is irradiated. . FIG. 4A qualitatively shows deformation of the diamond crystal plate 4 before deformation, and FIG. 4B qualitatively shows deformation of X (width direction) -Y (height direction) after thermal deformation. FIG. 5 shows the deformation of the surface of the diamond crystal plate 4 by 2 nm contour lines. According to the analysis of the thermal deformation in this way, the degree of deformation is somewhat larger on the joint portion 5A side, but the amount of deformation is extremely small near Y = 0 in the X-ray irradiation range A. Although not described in detail, the slope error when assuming Laue reflection on the lattice plane at Y = 0 is about 1/10 of the FWHM of the diffraction intensity curve at 8 keV, and there is no problem.

According to the above embodiment, since the diamond crystal plate 4, the element fixing base 3, and the base 1 are bonded by the bonding material that does not melt due to the thermal load of X-rays, the crystal becomes unstable. Can be stably supported.
Further, by attaching the diamond crystal plate 4 to the diamond single crystal element fixing base 3 via the lower end face, thermal deformation and distortion can be suppressed to a minimum, and the effective area suitable for diffraction of the diamond crystal plate 4 is improved. Can be done. Furthermore, since heat can be conducted from the element fixing base 3 having a large cross-sectional area to the base 1, heat can be radiated well. In addition, since the element fixing base 4 is made of a single crystal diamond of the same material as the crystal plate, the thermal expansion coefficient and the thermal conductivity can be made equal to effectively suppress the deformation at the time of joining and the deformation at the time of heat load. . In addition, in the joining portions 5A and 5B joined by the Sn-Ag solder, the joining surface made of the diamond single crystal is brazed by the silver solder 7 and the Ni thin film 8 is coated, so that the joining can be performed well by soldering. it can.

Further, since the cross-sectional area of the element fixing base 3 is formed sufficiently large with respect to the cross-sectional area of the diamond crystal plate 4, a thermal gradient at the time of X-ray irradiation can be reduced. Since the bonding area of the element fixing base 3 to the base 1 is set to be sufficiently large with respect to the area of the lower end face of the lower side 4, heat transfer can be improved. Further, since the joining surface of the element fixing base 3 to the diamond crystal plate 4 and the joining surface to the base 1 are formed parallel to each other, the deformation amount caused by the thermal expansion of the element fixing stand 3 can be made uniform. Thus, the influence on the diamond crystal plate 4 can be reduced.

Furthermore, by forming fine irregularities 9 on one or both of the joints between the diamond crystal plate 4 and the element fixing base 3 and the joint between the element fixing base 3 and the base 1, silver solder and The bonding strength can be increased by improving the wettability of the solder. FIG. 8 shows another embodiment of the supporting device for the optical element. In the above embodiment, the base 1 was arranged only on one side (lower side) of the diamond crystal plate 4 to enable heat conduction. On the other hand, in this embodiment, the base 1 and the opposing base 11 capable of transferring (dissipating) heat are arranged on two sides (upper side and lower side) of the symmetric position.
That is, the opposing base 11 in which the cooling channel 12 is formed is arranged at a symmetric position of the diamond crystal plate 4 of the base 1. The joints 5A and 5B on the base 1 side are the same as those in the previous embodiment, but the contact 5C between the upper side end face of the diamond crystal plate 4 and the opposing base 11 is heated by X-ray irradiation. A heat transfer material capable of maintaining the diamond crystal plate 4 and the opposing base 11 in contact with each other due to the surface tension due to melting when the load becomes about 50 ° C. or higher,
For example, low-temperature solder such as In-Ga or silver paste (A
g), liquid Ga or the like is used.

According to this embodiment, since the end face of the diamond crystal plate 4 symmetrical to the base 1 side is joined to the opposing base 11 via the joining portion 5C, the efficiency of the two bases 1 and 11 is improved. Heat can be radiated well. In addition, since the joining material of the joining portion 5C is configured to be melted when a thermal load is applied, the diamond crystal plate 4 is not restrained by the contact portion 5C of the opposing base 11, and thermal deformation is absorbed, and the diamond crystal plate There is no thermal distortion of 4.

[0028]

As described above, according to the first and third aspects of the present invention, since the two joining materials of the joining portion are not melted by the heat load, the crystal of the diamond crystal plate is fixed by the thermal shock. It does not become unstable. In addition, since the diamond crystal plate is attached to the element fixing base with a similar thermal expansion coefficient via its end face, deformation and distortion due to heat can be suppressed to a minimum, and the range of use that can be diffracted on the crystal surface is expanded. Can be. Further, since the heat of the diamond crystal plate loaded by X-rays can be transmitted well from the element fixing base to the base, heat can be dissipated effectively.

According to the second and fourth aspects of the present invention, since the element fixing base is made of diamond crystal, the coefficient of thermal expansion and the thermal conductivity are made very close to each other so that the deformation at the time of joining and the heat generated by X-ray irradiation are achieved. Deformation under load can be effectively suppressed. In addition, diamond crystals
Soldering can be performed by brazing with silver brazing and Ni coating, and the diamond crystal plate and the element fixing base and the element fixing base and the base can be satisfactorily joined.

According to the fifth aspect of the present invention, since the cross-sectional area of the element fixing base is formed to be large, a thermal gradient at the time of X-ray irradiation can be reduced. Has a large bonding area, so that heat transfer can be improved and the diamond crystal plate can be effectively cooled.

Further, according to the invention described in claim 6, the amount of deformation caused by thermal expansion of the element fixing base due to a thermal load can be equalized, and the influence on the diamond crystal plate can be reduced.

Further, according to the invention of claim 7, it is possible to increase the bonding strength between the crystal plate and the fixing base and the fixing base and the base by the brazing and soldering.

According to the eighth aspect of the present invention, the other end face of the diamond crystal plate is brought into contact with the opposing base by the heat transfer material, so that heat is efficiently conducted to the two bases and radiated. Can be. In addition, since the heat transfer material is configured to be melted at the time of heat load, the diamond crystal plate is not restrained at the joint of the opposing base and thermal deformation is absorbed. There is no thermal distortion of the plate.

[Brief description of the drawings]

FIG. 1 is an overall perspective view showing an embodiment of a support device for an optical element according to the present invention.

FIG. 2 is an exploded perspective view illustrating a joining portion of the support device.

FIG. 3 is a model diagram of a diamond crystal plate of the supporting device, which is an analysis diagram showing surface deformation when a thermal load is applied after joining.

4 (a) and 4 (b) are analytical views showing deformation of a crystal surface in the X-Y direction by modeling a diamond crystal plate, respectively. FIG. 4 (a) shows a thermal load before deformation, and FIG. 4 (b) shows a thermal load after bonding. This is the case.

FIG. 5 is an analysis diagram in which the deformation of the crystal surface when a thermal load is applied after bonding by modeling the diamond crystal plate and expressing the same by contour lines.

6 (a) and 6 (b) each show a modified example of a joint portion of the supporting device, wherein FIG. 6 (a) is an exploded view and FIG. 6 (b) is a partially enlarged sectional view.

FIG. 7 is a partially enlarged cross-sectional view showing another modified example of the joint portion of the support device.

FIG. 8 is a front sectional view showing another embodiment of the optical element support device according to the present invention.

[Explanation of symbols]

 A X-ray irradiation range 1 base 2 cooling channel (cooling means) 3 element fixing base 4 diamond crystal plate 5A, 5B joint 5C contact 6 solder 7 silver brazing 8 Ni film 9 uneven portion 11 opposing base 12 cooling channel

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroshi Sugiyama 1-1, Oho, Tsukuba City, Ibaraki Pref. High Energy Accelerator Research Organization (MRI) (72) Inventor: Koi Zhang, 1-1, Oho, Tsukuba, Ibaraki Prefecture (72) Toshio Takiya 1-7-89 Minami Kohoku, Suminoe-ku, Osaka-shi, Osaka Inside Hitachi Zosen Corporation (72) Inventor Akio Komura Minami-Suminoe-ku, Osaka-shi, Osaka 1-7-89 Kohoku, Hitachi Zosen Corporation (72) Inventor Kunihiko Yamazato 1-7-89, Minami Kohoku, Suminoe-ku, Osaka-shi, Osaka F-term in Hitachi Zosen Corporation 2G001 AA01 BA18 CA01 EA01 JA14 QA02 RA03 RA08 RA20 2H043 AE02

Claims (8)

[Claims] When mounting a diamond crystal plate to be irradiated with X-rays on a base, an end face of the diamond crystal plate is bonded to an element fixing base with a first bonding material that is not melted by a thermal load due to X-rays. Then, the element fixing base is mounted on the base with a second bonding material that does not melt under the heat load, and the diamond crystal plate, the element fixing base and the thermal expansion coefficient are approximated. A method for supporting an optical element, wherein a material having a good thermal conductivity is used for a base. 2. An element fixing base is formed of diamond, and a brazing silver is brazed to a joining surface between the diamond crystal plate and the element fixing base, and then the surface is coated with Ni to form a diamond crystal plate and the element fixing base. And soldering with the first bonding material, brazing a silver braze to the joining surface of the element fixing base to the base, coating the surface with Ni, and joining the element fixing base and the base. 2. The method for supporting an optical element according to claim 1, wherein said second bonding material is used for bonding after soldering. 3. A diamond crystal plate to be irradiated with X-rays, a base, an element fixing table interposed between the diamond crystal plate and the base, an end face of the diamond crystal plate and the element fixing table. A first bonding material that is not melted by a thermal load due to X-rays, and a second bonding material that is not melted by the thermal load that bonds the element fixing base and the base; A device for supporting an optical element, wherein a material having a good thermal conductivity is used for a diamond crystal plate, an element fixing table, and a base while approximating a thermal expansion coefficient of the fixing table. 4. The element fixing base is formed of diamond single crystal, and the first bonding material of the diamond crystal plate and the element fixing base is a silver solder brazed to a bonding surface of the diamond crystal plate and the element fixing base. A second joining between the element fixing base and the base, comprising a Ni thin film coated on the surface of the silver solder and a solder for joining the diamond crystal plate and the element fixing base via the silver solder and the Ni thin film; The materials are silver braze brazed to the bonding surface of the element fixing base, a Ni thin film coated on the surface of the silver braze, these silver braze and N
4. The optical element support device according to claim 3, wherein the device fixing base and the solder for joining the base via an i-thin film. 5. A cross-sectional area of the element fixing base is sufficiently large with respect to a cross-sectional area of the diamond crystal plate, and a bonding area of the element fixing base to the base with respect to an area of a bonding end face of the diamond crystal plate. 4. The apparatus according to claim 3, wherein the base is set to be sufficiently large, and cooling means is provided on the base.
Or the support device for an optical element according to 4. 6. The optical element according to claim 3, wherein a bonding surface to the diamond crystal plate and a bonding surface to the base in the element fixing base are formed parallel to each other. Support device. 7. The optical device according to claim 3, wherein a fine unevenness is formed on a bonding surface of each of the bonding portions between the diamond crystal plate and the element fixing base, and between the element fixing base and the base. Device supporting device. 8. An opposing base is disposed at a position symmetrical to the base of the diamond crystal plate, and the other end face of the diamond crystal plate is interposed through a heat transfer material which is in a molten state when subjected to a thermal load by X-rays. The support device for an optical element according to claim 3, wherein the device is in contact with the optical device.