Application of an X-ray Photon Selector

Abstract

The present invention discloses an application of an X-ray photon selector, wherein the X-ray photon selector of the present invention is used as an energy spectrometer or a monochromator; wherein the X-ray photon selector comprises a substrate, and a selection reflector located on the substrate, and the selection reflector comprises a series of alternating light-transmitting elliptical wave bands and light-impermeable elliptical wave bands; wherein the light-impermeable elliptical wave bands are regions on the substrate where quantum dot reflectors are photoetched, and the quantum dot reflectors are arranged according to a sine function or a cosine function and arranged quasi-randomly. Firstly, the present invention proposes for the first time to use the selector as an energy spectrometer or a monochromator, thereby reducing the optical elements in the spectrometer and the monochromator, promoting the lightweight of the spectrometer and the monochromator, and at the same time reducing the preparation cost of the spectrometer to a certain extent. Secondly, the selector of the present invention avoids the problems of high-order diffraction interference of traditional spectrometers and the high-order harmonic pollution of traditional monochromators; in addition, the X-ray photon selection in the present invention is also applicable to multiple photon energy regions.

Description

Technical Field

[0001] The present invention relates to the technical field of spectrometers, and in particular to the application of an X-ray photon selector. Background Art

[0002] At present, spectrometers are mainly used as scientific instruments for analyzing complex light. Spectrometers are usually composed of the following parts, including the incident system, collimation system, dispersion system, focusing system, and data collection and processing system. The incident system is usually composed of a slit; the collimation system is used to convert the incident light at the slit into parallel light, which is composed of lenses, reflectors, etc. or directly integrated into the dispersion element, such as a concave grating, but it is difficult to make and has a high cost; the dispersion system is usually composed of dispersion elements, such as gratings, crystals (multilayer films), etc., which are used to decompose the incident light into multiple monochromatic lights; and the focusing system is to focus the dispersed light beam through the focusing element and form a series of light spots on the focal plane, corresponding to the corresponding wavelength; finally, the light information is collected through the data collection and processing system, amplified and output, and processed into a spectrum, which is usually composed of a detector array and software. Therefore, traditional spectrometers are large in size, high in power consumption, and very bulky, which greatly limits their scope of application. Therefore, fiber optic spectrometers have also appeared, but the resolution of this type of spectrometer is poor, Δλ is about 1nm or 2nm, and is usually used for integration with other systems. The above-mentioned spectrometers are all based on the principle of dispersion. Through the dispersion element, complex light is decomposed into single-color light, but this will also introduce high-order diffraction, resulting in interference from high-order diffraction in the spectrum. By using filters to limit the wavelength to a certain band, the pollution of high-order harmonics can be effectively reduced, but it is difficult to make, resulting in increased costs and this method inevitably limits the spectrum measurement range. Under a wide-spectrum light source, high-order diffraction is particularly serious, and this grating / crystal spectrometer based on the principle of dispersion is difficult to obtain a true spectrum from the spectrum measurement.

[0003] There are two other spectrometers for measuring the spectrum in the X-ray energy spectrum band: energy response spectrometer and bandpass spectrometer. Energy response spectrometer analyzes the energy spectrum by depositing energy in the detector, so it can only be used for weak light. Bandpass spectrometer directly measures the X-ray energy spectrum in sections through the high-pass characteristics of the filter and the low-pass characteristics of the reflector. Their working principles determine that these two spectrometers can only be used in situations where the resolution requirements are not high. Summary of the invention

[0004] In order to solve the problem that the existing dispersion element introduces higher-order diffraction in the process of light decomposition, thereby causing interference of higher-order diffraction in the spectrum, and the problem that the existing dispersion element is composed of multiple optical elements, resulting in a heavy spectrometer body, the purpose of the present invention is to provide an application of an X-ray photon selector.

[0005] The technical solution of the present invention to solve the above technical problems is as follows: an X-ray photon selector is used as an energy spectrometer or a monochromator.

[0006] The beneficial effects of the present invention are: 1. Compared with the heavy spectrometers in the past, the X-ray photon selector in the present invention is simple and light when used as an energy spectrometer or monochromator, and can be applied to various application places including laboratories and industries; 2. When used as an energy spectrometer, it has higher spectral resolution and a wider spectrum measurement range; 3. Delta-like energy response, without errors caused by higher-order diffraction: when used as a spectrometer, there is no interference from higher-order diffraction, and when used as a monochromator, there is no high-order harmonic pollution, making the spectrum more accurate and the monochromatization performance better; 4. It is suitable for multiple energy spectrum ranges from X-rays to infrared.

[0007] On the basis of the above technical solution, the present invention can also be improved as follows:

[0008] When the X-ray photon selector is used as an energy spectrometer, the energy spectrometer also includes a detector.

[0009] Furthermore, the X-ray photon selector includes a substrate and a selection reflector located on the substrate, the selection reflector includes a series of alternating light-transmitting elliptical wave bands and opaque elliptical wave bands; wherein the opaque elliptical wave bands are areas on the substrate where quantum dot reflectors are photoetched, and the quantum dot reflectors are arranged according to a sine function or a cosine function and in a quasi-random arrangement.

[0010] The beneficial effects of adopting the above further technical solution are as follows: First, the present invention proposes for the first time to use the selector as an energy spectrometer or monochromator, thereby reducing the optical elements in the spectrometer, making the spectrometer lightweight, and at the same time reducing the preparation cost of the spectrometer to a certain extent. Secondly, the present invention can realize the collection and selection of different X-ray photons to different positions on the plane by only relying on the X-ray photon selector, making the photon selection instrument simple and lightweight in design, and the X-ray photon selector can be used as an energy spectrometer and a monochromator at the same time, avoiding the problem of high-order diffraction interference of traditional spectrometers and high-order harmonic pollution of traditional monochromators; in addition, the X-ray photon selection in the present invention is also applicable to multiple photon energy regions from soft X-rays to infrared.

[0011] Furthermore, when the energy region of the target photons is in the soft X-ray region or the extreme ultraviolet region, the arrangement spacing of the quantum dot reflectors is 50-500nm.

[0012] Furthermore, when the energy range of the target photons is in the visible light infrared region, the arrangement spacing of the quantum dot reflectors is 500nm-2μm.

[0013] The beneficial effect of adopting the above further technical solution is that the arrangement spacing between quantum dot reflectors is at the micro-nanometer level, which meets the resolution required for the X-ray photon selector to select target photons. In addition, the arrangement spacing of the quantum dot reflectors in the present invention is also closely related to the grating diffraction equation (mλ=d(sinα±sinβ). When the wavelength is smaller, the distance between the ellipse edges is smaller, so the arrangement spacing of the quantum dot reflectors also needs to be reduced. If the arrangement spacing of the quantum dot reflectors is too large, moiré fringes will be caused, affecting the diffraction effect of the X-ray photon selector.

[0014] Furthermore, the thickness of the quantum dot reflector is 20-100 nm.

[0015] The beneficial effects of adopting the above-mentioned further technical solution are: the quantum dot reflector within this thickness range has the best effect; if the thickness of the quantum dot reflector is less than this range, the quantum dot reflector is not effective in suppressing high-order diffraction; if the thickness of the quantum dot reflector is greater than this range, it will cause the substrate to tilt, thereby affecting the diffraction effect.

[0016] Furthermore, the preparation method of the X-ray photon selector comprises the following steps:

[0017] Step 1, draw multiple ellipse edges with equal spacing on the major axis on the base;

[0018] Step 2: First, draw the area where the quantum dot reflector needs to be photolithographically arranged within the elliptical edge according to a sine function or a required function, and then perform photolithography in a quasi-random arrangement to form a selection reflector composed of alternating opaque elliptical wave bands and transparent elliptical wave bands to obtain an X-ray photon selector.

[0019] The beneficial effects of adopting the above-mentioned further technical scheme are: 1. The X-ray photon selector prepared by elliptical edges with equal spacing can focus photons of different energies to different positions on the plane; 2. The X-ray photon selector obtained by this preparation method has high resolution and a wide spectral measurement range; 3. The obtained X-ray photon selector can suppress high-order diffraction during diffraction; 4. The quasi-random arrangement method is adopted during preparation, so that the X-ray photon selector is easy to process and manufacture.

[0020] Furthermore, the spacing of the ellipse edges on the major axis in step 1 is: The width of the ellipse edge is: Wherein, α is the incident angle, β is the diffraction angle, and α≠β, m is ±1, and λ is the diffraction wavelength.

[0021] Furthermore, in step 1, the substrate is a transparent material, and the substrate in step 1 is a transparent material, and the transparent material includes a wafer or single crystal silicon.

[0022] Furthermore, the material of the photolithography quantum dot reflector is a high-reflectivity material, and the reflectivity of the high-reflectivity material in the energy range of the target photon is greater than 90%.

[0023] The beneficial effect of adopting the above further technical solution is: in the present invention, if the reflectivity of the material used for the quantum dot reflector lithographically formed on the substrate is not high, light will lose part of its energy during reflection, resulting in low diffraction efficiency.

[0024] Beneficial effects:

[0025] The present invention intends to adopt a new technical idea to develop an X-ray photon selector, which can achieve the effect of spectrum measurement by selecting and focusing photons of different energies in the light source to different positions on the plane, and will not be affected by high-order diffraction. In addition, because the photon selector of the present invention can integrate the collimation system, the dispersion system and the focusing system into one, the selector in the present invention has a lightweight body; and the selector also has a high resolution and spectrum measurement range, suitable for a wide photon energy range from soft X-rays to infrared. And the selector in the present invention can not only be used for laboratory research; and because of its lightweight design, it is easy to combine with other systems, so it can also be used for industrial material analysis; expand the use environment of the selector in the present invention, and improve the competitiveness of the selector in the market. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the principle of the X-ray photon selector in the present invention;

[0027] Figure 2 It is a schematic diagram of the working mode of the X-ray photon selector in the present invention under the detection of a laboratory point light source;

[0028] Figure 3 It is a schematic diagram of some structures of the selected reflector in the present invention;

[0029] Figure 4 This is a simulation result diagram of the X-ray photon selector in the present invention;

[0030] Description of reference numerals:

[0031] 1-X-ray photon selector, 2-object, 3-detector. DETAILED DESCRIPTION

[0032] The application of the X-ray photon selector of the present invention will be described below in conjunction with embodiments.

[0033] However, the present invention may be exemplified in many different forms and should not be construed as limited to the specific embodiments set forth herein; rather, these embodiments are provided so that this invention will be thorough and complete and will fully convey the scope of the invention to those skilled in the art.

[0034] During the research on spectrometers, the inventors found that the dispersion elements in existing spectrometers are usually composed of multiple optical components. On the one hand, the existing dispersion elements only have the dispersion function and need to cooperate with multiple mechanical parts and other optical components, which makes the spectrometer heavy and inconvenient to move. On the other hand, the dispersion elements will introduce high-order diffraction when decomposing light with complex components into light of a single color, making it difficult to obtain a true spectrum from the spectrometer.

[0035] Based on this, firstly, the inventor adopted a new technical idea and developed an X-ray photon selector, which can select and focus photons of different energies in the light source to different positions on the plane, can achieve the effect of spectrum measurement, and will not be affected by high-order diffraction, and can integrate the collimation system, dispersion system and focusing system. Therefore, the X-ray photon selector in the present invention not only has a lightweight body, but also has a high resolution and a wide spectrum measurement range, which is suitable for target photons with energy ranges from soft X-rays to infrared. Secondly, the inventor will use the X-ray photon selector as a spectrometer or monochromator for the first time.

[0036] The present invention will be described in detail below.

[0037] An embodiment of the first aspect of the present invention provides a method for preparing an X-ray photon selector, comprising the following steps:

[0038] Step 1, draw multiple ellipse edges with equal spacing on the major axis on the base;

[0039] Step 2: First, draw the area where the quantum dot reflector needs to be photolithographically arranged within the elliptical edge according to a sine function or a required function, and then perform photolithography in a quasi-random arrangement to form a selection reflector composed of alternating opaque elliptical wave bands and transparent elliptical wave bands to obtain an X-ray photon selector.

[0040] The preparation method of the X-ray photon selector in this embodiment is relatively simple, which shortens the preparation time of the photon selector to a certain extent and reduces its preparation cost. Specifically, firstly, the X-ray photon selector prepared by elliptical edges with equal spacing can focus photons of different energies to different positions on the plane, and the prepared X-ray photon selector can suppress high-order diffraction during diffraction; secondly, the X-ray photon selector obtained by this preparation method has high resolution and wide spectral measurement range; finally, the quasi-random arrangement method is adopted during preparation, so that the X-ray photon selector is easy to process and manufacture.

[0041] In addition, the quasi-random arrangement in step 2 of this embodiment is specifically: when photolithography of quantum dot reflectors is performed on a substrate, the area where the elliptical edge lines are located is randomly distributed as points 0 or 1, forming a quasi-random arrangement; wherein 1 is a point that needs to be photolithographically provided with a quantum dot reflector, and 0 is a point that does not need to be photolithographically provided.

[0042] In addition, in some embodiments, the spacing between the multiple ellipse edges on the major axis in step 1 is: The width of the ellipse edge is: Wherein, α is the incident angle, β is the diffraction angle, and α≠β, m is ±1, and λ is the diffraction wavelength.

[0043] In addition, in some embodiments, a transparent material is usually selected as the substrate. The transparent material in this embodiment includes quartz or single crystal silicon. The quartz and single crystal silicon in the present invention both have good hardness, and can resist the problem of substrate deformation caused by the weight of the quantum dot reflector to a certain extent. In addition, the substrate in this embodiment can also be other materials with certain hardness and transparency, and the present invention will not further explain this in detail.

[0044] In addition, in some embodiments, the material of the quantum dot reflector photoetched on the substrate is usually a high-reflectivity material. The high-reflectivity material in this embodiment refers to a material with a reflectivity greater than 90% in the energy range of the target photon, such as gold. In this embodiment, if the reflectivity of the material used for the quantum dot reflector photoetched on the substrate is not high, light will lose part of its energy during reflection, resulting in low diffraction efficiency.

[0045] In addition, in some embodiments, the arrangement spacing between quantum dot reflectors photolithographically formed on the substrate will vary according to the energy range of the target photons. Generally, the arrangement spacing between quantum dot reflectors should be in the micro-nanometer range to meet the resolution required for the X-ray photon selector to select the target photons. Specifically, in this embodiment, when the energy range of the target photons is in the soft X-ray region or the extreme ultraviolet region, the arrangement spacing of the quantum dot reflectors on the substrate is 50-500nm. When the energy range of the target photons is in the visible infrared region, the arrangement spacing of the quantum dot reflectors on the substrate is 500nm-2μm.

[0046] In addition, in this embodiment, the area of ​​quantum dot reflector lithography is determined by the resolution required by the target photon energy region and the spectrum measurement range. Generally, the higher the resolution, the larger the area of ​​quantum dot reflector lithography. Figure 3 This is a partial structural diagram of a selection reflector prepared by using the first embodiment of the present invention, according to Figure 3 Schematic diagram, in which the white area is the photolithography quantum dot reflector area (i.e., the opaque elliptical waveband), and the black area is the non-photolithography area (i.e., the translucent elliptical waveband).

[0047] The second aspect of the present invention provides an X-ray photon selector prepared by using the embodiment of the first aspect of the present invention, the X-ray photon selector includes a substrate, and a selection reflector located on the substrate, the selection reflector includes a series of alternating transparent elliptical wave bands and opaque elliptical wave bands; wherein the opaque elliptical wave band is a region on the substrate where quantum dot reflectors are photoetched, and the quantum dot reflectors are arranged according to a sine function or a cosine function and arranged quasi-randomly. The X-ray photon selector in this embodiment can realize the collection and selection of different X-ray photons to different positions on the plane. The photon selection instrument in the present invention is simple and lightweight in design. The X-ray photon selector can be used as an energy spectrometer and a monochromator at the same time, avoiding the problem of high-order diffraction interference of traditional spectrometers and high-order harmonic pollution of traditional monochromators. In addition, the X-ray photon selection in the present invention is also applicable to multiple photon energy zones from soft X-rays to infrared, and can also integrate a collimation system, a dispersion system, and a focusing system.

[0048] In addition, in some embodiments, when the energy range of the target photons is in the soft X-ray region or the extreme ultraviolet region, the arrangement spacing of the quantum dot reflectors on the substrate is 50-500nm. When the energy range of the target photons is in the visible light infrared region, the arrangement spacing of the quantum dot reflectors on the substrate is 500nm-2μm. The arrangement spacing of the quantum dot reflectors in this embodiment is also closely related to the grating diffraction equation (mλ=d(sinα±sinβ). When the wavelength is smaller, the distance between the ellipse edges is smaller. Therefore, the arrangement spacing of the quantum dot reflectors also needs to be reduced. If the arrangement spacing of the quantum dot reflectors is too large, it will cause moiré fringes, affecting the diffraction effect of the X-ray photon selector.

[0049] In addition, in some embodiments, the thickness of the quantum dot reflector is 20-100 nm. In this embodiment, the quantum dot reflector within this thickness range has the best effect; if the thickness of the quantum dot reflector is less than the thickness within this range, the quantum dot reflector has an insignificant effect of suppressing high-order diffraction; if the thickness of the quantum dot reflector is greater than the thickness within this range, the substrate will be tilted, thereby affecting the diffraction effect.

[0050] The third aspect of the present invention provides an embodiment of using the X-ray photon selector in the first aspect as an energy spectrometer or a monochromator. In this embodiment, a simple and lightweight X-ray photon selector replaces the dispersion element in the existing spectrometer, reducing the number of optical elements in the spectrometer, which is beneficial to the lightweight of the spectrometer and the reduction of the preparation cost of the spectrometer to a certain extent. Moreover, compared with the traditional dispersion element, the X-ray photon selector in the present invention can not only separate photons of different energies, but also focus photons of different energies to different positions, so that it can meet the requirements of low-resolution imaging.

[0051] When the X-ray photon selector is used as an energy spectrometer, the energy spectrometer further comprises a detector. When in use, the detection surface of the detector coincides with the major axis direction of the elliptical wave band in the X-ray photon selector.

[0052] The following will be based on Figure 1 and Figure 2 The present invention is further described.

[0053] Figure 1 The schematic diagram of the principle of the X-ray photon selector in the present invention is as follows: Figure 1 It can be seen that the X-ray photon selector selects incident photons of different energies to positions on the plane through the selection mirrors arranged on the substrate. In addition, since the photons are focused to different positions on the spatial level, it can also be used as a monochromator through an adjustable slit.

[0054] The working mode of the X-ray photon selector in this embodiment under laboratory point light source detection is as follows Figure 2 shown; according to Figure 2 As shown in the figure, the light source irradiates the reflector (1) according to the designed object distance and incident angle, and focuses the photons of different energies to different positions on the spatial level at the corresponding diffraction angle. The detector (3) collects information to obtain the required measurement spectrum. Therefore, the combination of the X-ray photon selector and the detector can be used as a spectrometer.

[0055] Example:

[0056] Example 1

[0057] An X-ray photon selector is used to select photons with a photon energy of 92 eV. The selector constants in this embodiment are shown in Table 1:

[0058] Table 1. X-ray photon selector parameters

[0059] Parameter name Numeric Target photon energy 92eV(13.5nm) Object distance / image distance 280mm / 65mm Angle of incidence / angle of diffraction 2° / 5° RZP length meridian / sagittal 1.5mm / 0.3mm

[0060] Simulation analysis:

[0061] The off-axis cutout portion of the X-ray photon selector in Example 1 was tested and analyzed. Figure 3 The simulation results are shown in Figure 4 shown.

[0062] according to Figure 4 As shown in the figure, when the photon energy is 354eV (3.5nm, X-ray) incident on the X-ray photon selector at 2°, for the convenience of understanding, the photon energy is converted into wavelength according to the relationship between wavelength and photon energy. The change law of the wavelength (photon energy) focusing position and light intensity is as follows Figure 4As shown, its higher-order diffraction such as the secondary 177eV (7nm) and tertiary 118eV (10.5nm) are all well suppressed, and it has good focusing characteristics at 354eV. The half-width at half maximum in the dispersion direction is 52 microns. According to the Rayleigh criterion, the resolution can reach 380.

[0063] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An X-ray photon selector used as a spectrometer or monochromator; The X-ray photon selector comprises a substrate, and a selection reflector located on the substrate, wherein the selection reflector comprises a series of alternating light-transmitting elliptical wave bands and light-impermeable elliptical wave bands; wherein, The opaque elliptical waveband is a region on the substrate where quantum dot reflectors are photoetched, and the quantum dot reflectors are arranged according to a sine function or a cosine function and are arranged quasi-randomly; When the energy range of the target photons is in the soft X-ray region or the extreme ultraviolet region, the arrangement spacing of the quantum dot reflector is 50-500nm; when the energy range of the target photons is in the visible light infrared region, the arrangement spacing of the quantum dot reflector is 500nm-2μm; the thickness of the quantum dot reflector is 20-100nm.

2. The X-ray photon selector used as a spectrometer or a monochromator according to claim 1, characterized in that: When the X-ray photon selector is used as an energy spectrometer, the energy spectrometer further includes a detector.

3. A method for preparing an X-ray photon selector used as a spectrometer or a monochromator according to claim 1 or 2, characterized in that: The following steps are involved: Step 1, draw multiple ellipse edges with equal spacing on the major axis on the base; Step 2: First, draw the area where the quantum dot reflector needs to be photolithographically arranged within the elliptical edge according to the sine function or cosine function, and then perform photolithography in a quasi-random arrangement to form a selection reflector composed of alternating opaque elliptical wave bands and transparent elliptical wave bands to obtain an X-ray photon selector.

4. The preparation method according to claim 3, characterized in that: The spacing of the ellipse edges on the major axis in step 1 is: , the width of the ellipse edge is: , wherein α is the incident angle, β is the diffraction angle, and α≠β, m is ±1, and λ is the diffraction wavelength.

5. The preparation method according to claim 3, characterized in that: In step 1, the substrate is a transparent material, and the transparent material includes a wafer or single crystal silicon.

6. The preparation method according to claim 3, characterized in that: The material of the quantum dot reflector used for photolithography is a high-reflectivity material, and the reflectivity of the high-reflectivity material in the energy range of the target photon is greater than 90%.

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