Soller slit device and Soller slit system

Abstract

The present application discloses a Soller slit device and a Soller slit system, which relate to the field of high-energy radiation. The Soller slit device includes: a plurality of substrates, which are arranged on the optical path of X-rays, and the plurality of substrates are spaced and stacked along the vertical direction of the optical path, so that the X-rays are transmitted from the gaps between adjacent substrates, wherein the adjacent substrates are arranged non-parallel; a plurality of thin films, which are respectively deposited on the plurality of substrates, and are used to make the critical angle of the X-rays incident on the substrates less than 0.4 degrees, so as to gather the X-rays transmitted from the plurality of gaps, wherein the thin films include non-metallic thin films. In the above manner, the Soller slit device of the present application can effectively gather the X-rays, and irradiate the X-rays on the sample surface for use.

Description

Technical Field

[0001] The present application relates to the field of high energy radiation, and in particular to a Soller slit device and a Soller slit system. Background Art

[0002] In the field of scientific research, various technologies use high-energy radiation to conduct experiments, such as X-rays and extreme ultraviolet light. However, due to the nature of this high-energy radiation, it is usually difficult to control its divergence. In the field of high-energy radiation, a common optical element used to control the divergence of X-ray beams is a collimator, usually called a Soller slit. The slit includes an array of parallel plates or blades. Parallel plates or films are usually made of heavy metal sheets or highly absorbing metal sheets. However, the use of relatively thick metal foils to make films reduces the transmission efficiency of this Soller slit as the required divergence decreases. That is, as its design constraints become more stringent, the output quality of the device becomes worse. Secondly, parallel metal films usually produce curling or wrinkles, resulting in unpredictable divergence during X-ray transmission, and the cost of making metal films is also relatively high. Summary of the invention

[0003] The present application provides a Soller slit device and a Soller slit system.

[0004] In order to solve the above technical problems, a technical solution adopted in the present application is to provide a Soller slit device, which comprises:

[0005] A plurality of substrates are arranged on an optical path of X-rays, and the plurality of substrates are spaced and stacked in a direction perpendicular to the optical path so that the X-rays are transmitted from the gaps between adjacent substrates, wherein the adjacent substrates are arranged non-parallel; a plurality of thin films are deposited on the plurality of substrates respectively, and are used to make the critical angle of the X-rays incident on the substrates less than 0.4 degrees, so as to gather the X-rays transmitted from the plurality of gaps, wherein the thin films include non-metallic thin films.

[0006] In order to solve the above technical problems, another technical solution adopted in the present application is: to provide a Soller slit system, which includes the above Soller slit device and a radiation source.

[0007] The beneficial effects of the present application are as follows: different from the prior art, the Soller slit device of the present application is provided with a plurality of adjacent substrates, and the non-parallel arrangement of the adjacent substrates reduces the divergence of X-rays; secondly, the Soller slit device of the present application deposits a low-density non-metallic film on the substrate, thereby reducing the divergence rate of X-rays in the Soller slit, while maintaining a critical angle below 0.4 degrees, thereby improving the transmission efficiency of X-rays in the Soller slit; at the same time, the Soller slit device of the present application uses a non-metallic material to make a thin film, and its production cost is also relatively low. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a structural schematic diagram of an embodiment of the Soller slit device of the present application;

[0009] Figure 2 It is a schematic structural diagram of an embodiment of the film of the present application.

[0010] Figure 3 It is a curve schematic diagram of the reflectivity of a thin film formed on silicon deposited with polyimide having a thickness of 5 nm in the present application to a @17.4kevMo source;

[0011] Figure 4 It is a curve schematic diagram of the reflectivity of a thin film formed on silicon deposited with polyimide having a thickness of 50 nm in the present application to a @17.4kevMo source;

[0012] Figure 5 This is a curve diagram of the reflectivity of a 500nm thick polyimide film deposited on silicon to a @17.4kevMo source.

[0013] Figure 6 is a schematic structural diagram of another embodiment of the Soller slit device of the present application;

[0014] Figure 7 It is a structural schematic diagram of an embodiment of the Soller slit system of the present application. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0016] The present application first proposes a Soller slit device, such as Figure 1 As shown, Figure 1 1 is a schematic diagram of the structure of an embodiment of a Soller slit device of the present application. The Soller slit device 100 of this embodiment includes:

[0017] A plurality of substrates 110 are arranged on an optical path of X-rays, and the plurality of substrates 110 are spaced and stacked in a direction perpendicular to the optical path so that the X-rays are transmitted from the gaps between adjacent substrates 110, wherein the adjacent substrates 110 are non-parallel arranged; a plurality of thin films 120 are respectively deposited on the plurality of substrates 110, and are used to make the critical angle of the X-rays incident on the substrates less than 0.4 degrees, so as to gather the X-rays transmitted from the plurality of gaps, wherein the thin films 120 include non-metallic thin films.

[0018] like Figure 1As shown, the Soller slit device 100 is an optical element having a plurality of substrates 110, the substrates 110 being formed of an X-ray shielding material, each substrate 110 being perpendicular to the bottom surface 130, and being spaced apart from each other, and being arranged in a non-parallel manner so that the X-rays can be gathered through the gaps between the substrates 110. Therefore, if observed from a direction perpendicular to the bottom surface 130, the Soller slit device 100 is formed into a shape (arch) in which a small-diameter sector is cut out from a large-diameter sector, and the X-rays are injected from the large-diameter side of the Soller slit device 100, and are gathered and emitted from the small-diameter side through the gaps of the Soller slit device 100. In addition, considering that it is easy to arrange in an arch shape, the substrate 110 is preferably set to a rectangular shape, but it can also be other shapes. The housing of the Soller slit device 100 can be made of a hard material such as duralumin, and the angular spacing of the plurality of substrates 110 can be precisely maintained.

[0019] The film 120 is deposited on the substrate 110 . When the X-rays are transmitted from the gaps between the substrates 110 , the non-metallic film 120 can reduce the divergence rate of the X-rays and improve the transmission efficiency of the X-rays.

[0020] The Soller slit device 100 prevents divergent X-rays from passing through the slits of the Soller slit device 100 while allowing non-divergent X-rays to pass through. Therefore, a plurality of X-rays may be incident on the Soller slit device 100, and only X-rays parallel to or nearly parallel to the substrate 110 of the Soller slit device 100 pass through.

[0021] Different from the prior art, the Soller slit device 100 of the present application is provided with a plurality of adjacent substrates 110. The non-parallel arrangement of the adjacent substrates 110 reduces the divergence of X-rays. Secondly, the Soller slit device 100 of the present application deposits a low-density non-metallic film on the substrate, which reduces the divergence rate of X-rays in the Soller slit. While maintaining the critical angle less than 0.4 degrees, the transmission efficiency of X-rays in the Soller slit is improved. At the same time, the Soller slit device 100 of the present application uses a non-metallic material to make a film, and its production cost is relatively low.

[0022] Optionally, the non-metallic film of the present application includes SiO x 、SiN x 、SiO x N y 、Al x O y 、Al x Si y O z A film 120 made of any one or any combination of Si, a-Si, poly-Si and polyimide.

[0023] See also Figure 2 , Figure 2Schematic diagram of the structure of an embodiment of the film of the present application. Figure 2 As shown, in this embodiment, the film 120 can be made of a combination of polyimide and silicon, wherein the polyimide is deposited on the silicon. The silicon is disposed between the polyimide and the substrate 110, and the thickness of the polyimide can be 5 to 500 nm. Figure 3-5 , Figure 3 It is a curve schematic diagram of the reflectivity of a thin film formed on silicon deposited with polyimide having a thickness of 5 nm in the present application to a @17.4kevMo source; Figure 4 It is a curve schematic diagram of the reflectivity of a thin film formed on silicon deposited with polyimide having a thickness of 50 nm in the present application to a @17.4kevMo source; Figure 5 1 is a curve diagram showing the reflectivity of a 5 nm thick polyimide film deposited on silicon to a @17.4kevMo source. Figure 3-5 As shown, when the film 120 is made of 5nm polyimide deposited on silicon, its reflection effect on X-rays is better, and when the incident angle is less than 0.1 degrees, it is totally reflected. It can be seen that the critical angle of X-rays is less than 0.1 degrees at this time.

[0024] Please refer to the table below, which shows the critical angles of different non-metallic thin film materials selected for different X-ray sources in this application.

[0025]

[0026] It can be seen that when the film 120 is polyimide, when the radiation source is Cr, the critical angle of the X-ray is 0.28 degrees, when the radiation source is Cu, the critical angle of the X-ray is 0.19 degrees, and when the radiation source is Ru, the critical angle of the X-ray is 0.086 degrees.

[0027] When the film 120 is SiOx, SiNx, SiOxNy, AlxOy or AlxSiyOz, and the radiation source is Cr, Cu or Ru, the critical angle of the X-ray is less than 0.4 degrees.

[0028] That is, when the metal film 120 is made of any one or any combination of SiOx, SiNx, SiOxNy, AlxOy, AlxSiyOz, a-Si, poly-Si and polyimide, the present application can make the critical angle of X-rays when they are gathered through the gap between the substrates 110 of the Soller slit device 100 less than 0.4 degrees, thereby improving the transmission efficiency of X-rays in the Soller slit.

[0029] Optionally, the mass density of the film 120 is less than 5 g / cm 3 .

[0030] The film 120 is made of any one or any combination of SiOx, SiNx, SiOxNy, AlxOy, AlxSiyOz, a-Si, poly-Si and polyimide, wherein the mass density of polyimide is 1.33 g / cm 3 , SiO x The mass density is 2.65g / cm 3 , Al x Si y O z The mass density is 2.7 g / cm 3 , SiO x N y The mass density is 2.81 g / cm 3 , SiN x The mass density is 3.17g / cm 3 , Al x O y The mass density is 3.95g / cm 3 The smaller the mass density of the film 120 is, the greater the reflectivity to X-rays is, so the mass density of the manufactured film 120 should be less than 5 g / cm3.

[0031] Optionally, when manufacturing the substrate 110, the substrate 110 can be made of any one or any combination of Kapton foil, polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), glass, mica, highly oriented graphite (HOPG), sapphire, graphene, quartz, lithium fluoride (LiF) and magnesium oxide (MgO).

[0032] The thickness of the substrate 110 is 5 mm to 500 mm. One of the functions of the substrate 110 is mainly based on the function of supporting materials.

[0033] When slits with very dense spacing need to be made and a high X-ray transmittance is required, the substrate 110 can be a flexible Kapton foil, polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), etc., which have the characteristics of low production cost and thin substrate. The substrate 110 can be set to a thickness of several millimeters, which makes it easier to make slits with very dense spacing, and the transmittance to X-rays can be higher. At the same time, very parallel angles can be made, which is suitable for ultra-fine angle selection.

[0034] However, the flexible substrate is easy to be damaged, and long-term X-ray radiation can easily cause aging. At the same time, it is not adaptable to external environments such as acid and alkali. Therefore, the Soller slit life of the flexible substrate is short.

[0035] When better adaptability to the external environment is required and the precision requirement is not high, the substrate 110 can be a hard substrate, such as glass, mica, highly oriented graphite (HOPG), sapphire, graphene, quartz, lithium fluoride (LiF) and magnesium oxide (MgO), etc., which are very stable and have good hardness. They have a very good supporting effect on the material, and the coating is not easy to fall off. They have a high thermal expansion coefficient and no damage, and have high tolerance to long-term X-ray radiation. At the same time, they have the advantages of good adaptability to external environments such as acids and alkalis. However, this type of substrate 110 has a high cost and is difficult to cut thin when making the substrate 110. It is generally several hundred millimeters thick. It is not easy to make slits with very dense spacing in the process itself, and the transmittance to X-rays is low.

[0036] Therefore, when manufacturing the Soller slit device 100 , different materials mentioned above may be selected to manufacture the substrate 110 according to production requirements, which is not limited here.

[0037] Optionally, the substrate 110 has a first main surface and a second main surface that are oppositely disposed, and the film 120 is deposited on the first main surface and / or the second main surface. When the film 120 is deposited on both the first main surface and the second main surface of the substrate 110, the transmission efficiency of the X-rays will be higher, and the divergence of the X-rays can be reduced.

[0038] like Figure 1 As shown, the substrate 110 of the Soller slit device 100 has a first main surface and a second main surface that are relatively arranged. In order to allow the X-rays to be reflected and transmitted on multiple substrates 110, a thin film 120 needs to be deposited on the first main surface and the second main surface of the substrate 110, so that the X-rays will be gathered by the thin film 120 regardless of whether they are transmitted to the two main surfaces of the substrate 110, thereby improving the transmission efficiency of the X-rays.

[0039] Optionally, the thickness of the deposited thin film 120 may be set to 5 μm to 1 μm.

[0040] The deposition thickness of the thin film 120 is 0.5 μm to 1 μm, which can reduce the transmission of X-rays. If the thickness of the thin film is smaller, the reflectivity of the X-rays will be reduced, resulting in a decrease in the transmission rate of the X-rays.

[0041] Optionally, the number of layers of the non-metallic film deposited on the first main surface and / or the second main surface is greater than 1, that is, when the non-metallic film 120 is deposited on the substrate 110, multiple depositions may be performed to improve the reflectivity of X-rays.

[0042] Optionally, the thin film 120 is deposited on the substrate 110 by a deposition method including physical vapor deposition, chemical vapor deposition, electron beam evaporation, roll-to-roll, wet coating of organic materials, spin coating, and blade.

[0043] like Figure 6 As shown, Figure 6 It is a structural schematic diagram of another embodiment of the Soller slit device of the present application. Any X-rays incident into the Soller slit will be reflected, and almost all of the X-rays are reflected below the critical angle θc, and the reflection intensity will quickly drop to 1 / θ4, so the angle of the Soller slit is Φ±θc.

[0044] Any X-ray from the virtual source will be limited to Φ±(dθ / 2+θc). Any X-ray angle far from the virtual source will be limited to Φ±((R / L+1)dθ+θc), the ray comes from R*(R / L+1)dθ away from the virtual source point, so for any Φ, the angle selection of the Soller slit will be (R / L+1)dθ+θc, (R / L+1)dθ is determined by the geometry of the Soller slit, and θc is determined by the material of the film. The present application can reduce the critical angle of the X-ray incident on the Soller slit by selecting a low-density film 120.

[0045] The present application further proposes a method for calculating the critical angle of the Soller slit, which shows the neutron refractive index for X-rays and the neutron refractive index for thin films. In the case of neutrons, the refractive index is complex, and the refractive index n = 1-δ + iβ.

[0046] For X-rays, the values ​​of δ and β can be calculated from the atomic scattering coefficients (f1 and f2) using the following formula:

[0047]

[0048]

[0049] Among them, r e is the classical electron radius, which is 2.8179403*10 -15 m, λ is the wavelength of the detected X-rays, n a is the number density.

[0050]

[0051] Where ρ is the physical density in g / cm 3 , N a is Avogadro's constant, in mol -1 , M a is the molar mass in g / mol.

[0052] When the real part δ of the refractive index n is known, the critical angle θc is calculated as follows:

[0053]

[0054] Note that the critical angle θc is in radians.

[0055] For a pair of elements, we calculate the critical angle using the weighted sum of the contributions of each element. The critical angle θc is calculated as follows:

[0056]

[0057] where c i is the weighting coefficient (concentration, or stoichiometric number in chemical formula).

[0058] This angle varies depending on the electron density of the material. The greater the angle of the incident X-ray relative to the critical angle, the deeper the X-ray can penetrate into the material. For materials with an ideal flat surface, the reflectivity drops suddenly at angles above the critical angle, which is similar to θ*10. -4 Proportional.

[0059] The present application further proposes a Soller slit system 200, see Figure 7 , Figure 7 2 is a schematic diagram of a structure of an embodiment of a Soller slit system of the present application. The Soller slit system 200 includes any one of the Soller slit devices 100 and a radiation source 140, and the radiation source 140 may include X-ray radiation. The radiation source 140 may be set as a radiation source of Cr, Cu and Ru.

[0060] The beneficial effects of the present application are as follows: different from the prior art, the Soller slit device 100 of the present application is provided with a plurality of adjacent substrates 110, and the non-parallel arrangement of the adjacent substrates 110 reduces the divergence of X-rays. Secondly, the Soller slit device 100 of the present application deposits a low-density non-metallic film on the substrate, which reduces the divergence rate of X-rays in the Soller slit, and improves the transmission efficiency of X-rays in the Soller slit when the critical angle is less than 0.4 degrees. At the same time, the Soller slit device 100 of the present application uses a non-metallic material to make a film, and its production cost is also relatively low.

[0061] The above descriptions are merely embodiments of the present application and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A Soller slit device, It is characterized in that include: A plurality of substrates are arranged on the optical path of the X-rays, and the plurality of substrates are spaced and stacked in a vertical direction of the optical path so that the X-rays are transmitted from the gaps between adjacent substrates, wherein the adjacent substrates are arranged non-parallel; A plurality of thin films, respectively deposited on the plurality of substrates, for making the critical angle of the X-ray incident on the substrate less than 0.4 degrees, so as to gather the X-ray transmitted from the plurality of the gaps, wherein the thin films include non-metallic thin films; Wherein, the non-metallic film comprises SiO x 、SiN x 、SiO x N y 、Al x O y 、Al x Si y O z , a-Si, poly-Si and polyimide, or any combination thereof; the mass density of the non-metallic film is less than 5g / cm 3 ; The thickness of the non-metallic film is 0.5 μm to 1 μm; the substrate is made of any one or any combination of Kapton foil, polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), glass, mica, highly oriented graphite (HOPG), sapphire, graphene, quartz, lithium fluoride (LiF) and magnesium oxide (MgO).

2. The Soller slit device according to claim 1, It is characterized in that The substrate is provided with a first main surface and a second main surface which are arranged opposite to each other, and the thin film is deposited on the first main surface and / or the second main surface.

3. The Soller slit device according to claim 2, It is characterized in that The number of layers of the non-metallic thin film deposited on the first main surface and / or the second main surface is greater than one.

4. The Soller slit device according to claim 1, It is characterized in that The deposition methods of the thin film on the substrate include physical vapor deposition, chemical vapor deposition, electron beam evaporation, roll-to-roll, wet coating of organic materials, spin coating and blade.

5. A Soller slit system, It is characterized in that The invention comprises the Soller slit device and the radiation source as described in any one of claims 1 to 4.

6. The Soller slit system according to claim 5, It is characterized in that The radiation source includes X-ray radiation.

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