JP2013088250A - X-ray waveguide, method for manufacturing x-ray waveguide, and method for controlling x-ray waveguide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a decrease in X-ray propagation efficiency in an X-ray waveguide composed of a core part and a clad part having a periodic structure.
In an X-ray waveguide having a configuration in which multiple interference of X-rays in a core portion made of a material having a structure periodicity is confined by total reflection at an interface with a cladding material provided outside the core, An X-ray waveguide having means for controlling a positional relationship between opposing components, with the components having a core portion and a cladding portion facing each other with the core portion facing inward.
[Selection] Figure 5

Description

  The present invention relates to an X-ray optical element applicable to X-ray imaging, X-ray exposure, and the like, and in particular, an X-ray waveguide capable of obtaining X-rays having spatially uniform phases, a method for manufacturing the X-ray waveguide, And a method for controlling the X-ray waveguide.

  When dealing with an electromagnetic wave having a short wavelength of several tens of nm or less, the difference in refractive index with respect to the electromagnetic wave between different substances is very small, and the reflectance for an incident angle larger than a very small total reflection critical angle is very small. For this reason, an optical element different from an optical system such as visible light is used for the X-ray optical system. For example, a total reflection mirror using total reflection at a low angle, an X-ray waveguide using total reflection, a diffraction grating or multilayer mirror using diffraction caused by a periodic structure of a crystal or a multilayer film, a Fresnel zone Plates and the like. In recent years, an X-ray optical system using an X-ray waveguide for confining and propagating an electromagnetic wave in a thin film or multilayer film has been proposed with the aim of reducing the size and performance of the X-ray optical system. Specifically, a flat plate thin-film waveguide (Non-Patent Document 1) in which a thin film of a low electron density material is sandwiched between high electron density materials and a plurality of flat plate X-ray waveguides that confine X-rays by total reflection are adjacent to each other. This is an optical system using an X-ray waveguide (Non-Patent Document 2) and the like arranged in the same manner.

Physical Letters, Volume 100, p. 184801 (2008) Physical Review B, Volume 62, Number 24, p. 16939 (2000-II)

  The waveguide disclosed in Non-Patent Document 1 includes an X-ray waveguide clad made of nickel and an X-ray waveguide core made of carbon. In this waveguide, X-rays are confined and guided by total reflection at the interface between carbon and nickel. In order to guide the single-layer waveguide having this configuration in a state where the phases of the X-rays are aligned, it is necessary to set the core width of the waveguide to an extremely small value. Cannot be increased. The waveguide disclosed in Non-Patent Document 2 is a laminate of the single-layer waveguide. For this reason, it becomes possible for the combination of cores sandwiched between clads to guide X-rays with a large amount of light as compared to a single-layer waveguide. However, in the waveguide having such a configuration, each of the laminated waveguide configurations (a set of a core and a clad sandwiching the core) functions as a separate single-layer waveguide. For this reason, the advantages of the single-layer waveguide are reduced, such that the phases of the X-rays emitted as a whole are uniform, and the light collection and divergence suppression effects are achieved.

In order to solve the above problems, the present invention provides a plurality of components having a cladding portion and a core portion in which a plurality of components having different real refractive index portions are periodically arranged on the cladding portion. An X-ray waveguide facing the core portion inside,
The periods of the plurality of components of the core portion of the component facing each other are equal,
The total reflection critical angle at the interface between the cladding part and the core part is larger than the Bragg angle corresponding to the structural period of the core part with respect to X-rays having the same wavelength,
And the total reflection critical angle at the interface of a plurality of components having different real part of the refractive index forming the core part is smaller than the Bragg angle,
An X-ray waveguide comprising: means for controlling a positional relationship between at least one first component of the components and a second component facing the first component About.

Further, the present invention includes forming a core part in which a plurality of components having different real refractive index parts are periodically formed on the clad part to produce a component of the X-ray waveguide;
A plurality of the constituent elements having a core portion having the same structural period, and arranging the constituent elements facing each other with the core portion inside, and
Providing a mechanism capable of controlling the positional relationship between at least one first component of the components and a second component facing the first component. The present invention relates to a featured X-ray waveguide manufacturing method.

In addition, the present invention provides a plurality of components having a cladding part and a core part in which a plurality of components having different real refractive index parts are periodically formed on the cladding part, the core part being inward. In the X-ray waveguide facing the component,
Based on the periodic structure by controlling the positional relationship between at least one first component of the components and a second component facing the first component with the core portion inside. The present invention relates to a method for controlling an X-ray waveguide characterized by causing X-rays to resonate.

  According to the X-ray waveguide of the present invention, a plurality of X-ray waveguide components having a structure in which a core portion made of a periodic structure is formed on a flat clad member are combined, and the positional relationship is precisely controlled. Therefore, it is possible to suppress a decrease in the X-ray propagation efficiency due to the roughness of the core surface.

It is a schematic diagram for demonstrating the most basic structure of the X-ray waveguide concerning this invention. It is a schematic diagram for demonstrating the structure of the periodic structure used for the core part of the X-ray waveguide of this invention. It is a schematic diagram for demonstrating the conditions calculated | required by the structural period of the periodic structure used for the core part of the X-ray waveguide of this invention. It is a schematic diagram for explaining the roughness of the interface between the core and the clad on the surface side. It is a schematic diagram for demonstrating an example of the structure of the X-ray waveguide of this invention. It is a schematic diagram for demonstrating the principle of the X-ray waveguide of this invention. It is a schematic diagram which shows the form of the X-ray waveguide of this invention containing more than two components. In description of the Example of this invention, it is a schematic diagram for demonstrating control with respect to incident X-ray of the position of the fixed 1st component. In description of the Example of this invention, it is a schematic diagram for demonstrating the mechanism which adjusts the positional relationship of the 2nd component with respect to the 1st component. In description of the Example of this invention, it is a schematic diagram for demonstrating the structure and control axis | shaft of the whole waveguide.

  Hereinafter, the present invention will be described in detail.

  In the present invention, X-ray refers to an electromagnetic wave having a wavelength band in which the real part of the refractive index of a substance is 1 or less. Specifically, it refers to an electromagnetic wave having a wavelength of 100 nm or less, including extreme ultraviolet light (at 1 pm or more) (Extreme Ultra Violet (EUV) light). The frequency of such short-wave electromagnetic waves is very high, and the outermost electrons of the material cannot respond. Therefore, unlike the frequency band of electromagnetic waves (visible light and infrared rays) having a wavelength longer than the wavelength of ultraviolet light, X-rays It is known that the real part of the refractive index of a substance is smaller than 1. The refractive index n of a substance for such X-rays is generally expressed by the following formula (1)

The amount of deviation δ from 1 in the real part and the imaginary part related to absorption

It is expressed using δ it will be the real part of the larger material as the refractive index of the electron density is proportional to the electron density [rho _e materials is reduced. The real part of the refractive index is

It becomes. Furthermore, ρ _e is proportional to the atomic density ρ _a and the atomic number Z. As described above, the refractive index of a substance with respect to X-rays is represented by a complex number. In this specification, the real part is referred to as the real part of the refractive index or the real part of the refractive index, and the imaginary part is the imaginary part of the refractive index or the refractive index. Called the imaginary part. In the X-ray band, the substance whose refractive index real part is 1 at maximum is a vacuum, and a gas typified by air has almost the same refractive index as that of vacuum, but the refractive index of almost all substances other than gas is real. The part has a value smaller than 1. In the present specification, the terms “component”, “material”, and “substance” also apply to gases such as vacuum and air.

  Next, the X-ray waveguide used in the present invention will be described.

  The present inventors provide an X-ray waveguide that includes a clad and a core and confines X-rays in the core by total reflection at the interface between the core and the clad. An X-ray waveguide in which materials are periodically arranged was produced. In this waveguide, the X-rays guided through the core cause multiple interference, and a mode that efficiently guides in accordance with this periodic structure is selected. It becomes possible to guide the line.

  This waveguide confines and guides X-rays in the core by total reflection at the interface between the core and the cladding. In general, the total reflection of X-rays at the interface depends on the roughness of the interface, and it is known that the reflectance increases greatly as the roughness is reduced. Therefore, when the roughness of the interface between the core and the clad of the X-ray waveguide is large, the X-ray confinement efficiency is lowered and the propagation efficiency of the waveguide is reduced.

  The basic configuration of the X-ray waveguide fabricated by the present inventors is to guide X-rays in a wavelength band in which the real part of the refractive index of the substance is 1 or less, as schematically shown in FIG. A core part 11 and a clad part 14 for confining X-rays in the core part by total reflection at the interface, the core part is composed of components 12 and 13 that form a plurality of core parts having different real parts of refractive index. It has a structure in which a periodic structure is formed, and the X-ray total reflection critical angle at the interface between the core part and the cladding part is configured to be larger than the Bragg angle resulting from the structure period of the core part. It is characterized by being. A base 15 for improving mechanical strength may be provided outside the clad portion. Since the refractive index of a substance with respect to X-rays depends on the electron density in the substance, it can be said that the plurality of components having different real parts of the refractive index are a plurality of components having different electron densities in many cases.

  The X-ray waveguide of the present invention is a unique X-ray that has been discovered by the present inventors, in which X-rays that cause multiple interference due to the periodic structure of the components forming the core are guided in the core with low propagation loss. The wave guide phenomenon is used. This peculiar X-ray waveguide mode is formed by the structure periodicity, and the positions of the antinodes and nodes of the electric field intensity distribution of the X-ray coincide with the positions in the respective substance regions constituting the basic structure. At this time, the propagation loss of the waveguide mode in which the electric field intensity of the X-ray is concentrated on the material having a low electron density of the periodic structure is smaller than that of the other waveguide modes. It can be taken out. Hereinafter, this waveguide mode is referred to as a periodic resonance waveguide mode. In order to construct the X-ray waveguide of the present invention that enables this periodic resonant waveguide mode, several conditions must be satisfied. This will be described in detail below.

  First, a core part having a structure in which a plurality of components having different real refractive index parts form a periodic structure will be described. Here, the plurality of components includes any combination that can define a stable periodic structure, and as described above, the definition of components includes vacuum and air. That is, a material in which a material and an air gap alternately form a periodic structure can be used as the core portion of the present invention. The periodic structure here does not ask | require the dimension of a structure period. That is, one-dimensional, two-dimensional, and three-dimensional periodic structures can be applied. Here, the one-dimensional periodic structure is a structure in which a plurality of layered materials have periodicity in the stacking direction as shown in FIG. A two-dimensional periodic structure is a structure in which structural units having an infinite extent in one direction as shown in FIG. 2B are two-dimensionally regularly arranged in a cross section. There are hexagonal arrangement and cubic arrangement. In the three-dimensional periodic structure, for example, a structural unit such as a sphere shown in FIG. 2C is formed by cubic close packing or hexagonal close packing, or a plurality of components are phase-separated with structural regularity. Something like a double gyroid structure is included.

  When such a periodic structure is present, X-ray scattering that occurs at the interface between a plurality of materials causes interference, and the scattered X-rays intensify like the X-ray diffraction of a crystal and cause clear diffraction. When the structure period of the core of the waveguide used in the present invention is at a level comparable to the wavelength of X-rays (1 nm to several tens of nm), there is no structural regularity at the atomic level in each member. X-ray diffraction is observed. When the structure regularity is high, multiple interference occurs, and as a result, X-rays exhibit a unique propagation behavior in the regular structure. As described above, the X-ray waveguide of the present invention utilizes this multiple interference of X-rays. Therefore, the structural period of the core part used in the present invention is also preferably in the range of 1 nm to 50 nm. In addition, the number of periodic structures in the core region is preferably in the range of about 10 to 500 layers. When the number of layers is too small, the transmittance of the waveguide tends to decrease. As a result, the thickness of the core part is preferably about 10 nm to 10 μm.

  The core material having the structural periodicity of the X-ray waveguide of the present invention has a structure in which an artificial multilayer film or a molecular assembly of an amphiphilic material typified by a surfactant and an inorganic substance are regularly arranged. A mesostructured film (organic-inorganic mesostructured film), a mesoporous material film obtained by removing an amphiphilic material from the mesostructured film, a film having a regular structure formed by microphase separation of a block copolymer, etc. Can be used. However, any material that can cause multiple interference of X-rays can be used without being limited thereto.

  The artificial multilayer film is a laminate of a plurality of materials with a predetermined thickness by a technique such as sputtering or vapor deposition. The period of the structure can be freely controlled by the film formation time, but the structures that can be formed are There are limitations such as being limited to a one-dimensional periodic structure.

  The mesostructured film is formed by applying a precursor solution containing an amphiphilic material typified by a surfactant and an inorganic precursor onto the substrate, and causing the surfactant and inorganic species to self-assemble on the substrate. Is a film having a periodic structure of about 2 nm to 50 nm. In this case, the surfactant (amphiphilic material) is also referred to as a structure-directing agent. By changing the surfactant, the inorganic precursor, the concentration thereof, and the like, the dimension, symmetry, and structure period of the regular structure in the film can be changed. In particular, a mesoporous film produced by removing a surfactant from a produced surfactant-inorganic material mesostructured film is a film having a structure in which air and inorganic substances are regularly arranged three-dimensionally, and X It is a material that is preferably used in the present invention in the sense that it enables low-loss X-ray propagation by concentrating the line in a low-loss cavity.

  A block copolymer is a polymer compound in which a plurality of polymer segments having different properties are linked by a covalent bond, and forms a regular microphase separation structure depending on the properties and molecular weights of the constituent components. It is also possible to control the symmetry of the regular structure obtained by controlling the molecular weight of each segment. A periodic structure having a high electron density contrast can also be manufactured using a material that can be converted into an inorganic substance. The block copolymer has a feature that an ordered structure can be formed by a simple process such as heating after being applied to a substrate.

  Next, the cladding part will be described. As described above, the clad has a function of confining X-rays that have been subjected to multiple interference by the periodic structure of the core in the core by total reflection. The X-ray total reflection critical angle for a material is determined by the wavelength of the X-ray used and the electron density of the material. The higher the electron density, the lower the refractive index, and thus the larger the total reflection critical angle. As described above, since the Bragg angle corresponding to the periodic structure of the core needs to be smaller than the total reflection critical angle, when the clad is formed of a material having a low electron density, the Bragg angle of the core is reduced. In general, it is preferable to form the cladding material with a substance having a high electron density because the structure period needs to be increased, which may lead to a decrease in the structural regularity. For example, tungsten, tantalum, gold, bismuth and the like are preferably used.

  As described above, the X-ray waveguide of the present invention is a total reflection at the core-cladding interface so that X-rays that have undergone multiple interference in the core made of a material having a periodic structure do not come out of the core, It is necessary to confine X-rays in the core. In other words, the condition that the Bragg angle corresponding to the periodic structure of the core material constituting the waveguide is inevitably smaller than the total reflection critical angle at the core-cladding interface is necessary. FIG. 3A schematically shows this configuration, and X-rays that have undergone multiple interference are totally reflected at the cladding interface. When this condition is not satisfied, as described in FIG. 3B, the X-rays that have undergone multiple interference largely leak from the core member to the clad member and do not function as a waveguide. The above can be expressed using mathematical formulas as follows.

The total reflection critical angle θ from the direction parallel to the film surface, where n _{clad is} the real part of the refractive index of the material on the clad side and n _core is the real part of the refractive index of the material on the core side at the interface between the clad and the core _c-total (°) is n _clad <n _core ,

It is expressed.

When the structure period of the periodic structure forming the core is d, the Bragg angle θ _B (°) is defined as follows regardless of the presence or absence of multiple diffraction in the core.

m is a constant, and λ is the wavelength of X-rays. The physical property parameter of the substance constituting the X-ray waveguide of the present invention, the structure parameter of the waveguide, and the wavelength of the X-ray need to satisfy the following equations.
θ _B <θ _c-total

  In the present invention, it is necessary that another condition is satisfied. This will be described. When the periodic structure is composed of a plurality of components having different real parts of the refractive index, it is necessary to consider X-ray reflection at the interface between the components. In order for the X-ray waveguide of the present invention to function, multiple interference derived from the periodic structure must occur. When total reflection occurs at the interface of the material constituting the periodic structure, for example, as schematically shown in FIG. 3C regarding the one-dimensional periodic structure, X-rays are among the materials forming the laminated structure. As a result of being confined in the highest refractive index component and hindering multiple interference, the object of the present invention cannot be achieved. In other words, the unit constituting the periodic structure functions as a multi-total reflection X-ray waveguide, resulting in the same structure as a conventional flat plate waveguide. Therefore, it is necessary that the total reflection critical angle at the interface between components having different real parts of the refractive index forming the periodic structure of the core is smaller than the Bragg angle. This can be expressed as follows using mathematical formulas.

When the total reflection critical angle between different components of the real part of the refractive index constituting the periodic structure of the core is θ _{c_multi} (°), the following equation is satisfied.
θ _{c_multi} <θ _B

  When the conditions described above are satisfied, the waveguide mode confined by total reflection at the interface between the clad and the core can be localized in the core. Effective propagation angle measured from the direction parallel to the membrane

Is expressed by the following equation using a wave number vector (propagation constant) k _z in the propagation direction of the waveguide mode and a wave number vector k _o in vacuum.

  As described above, in the X-ray waveguide of the present invention, only the waveguide mode X-rays that resonate with the period of the regular structure due to multiple interference can be selectively propagated with low loss. The X-rays of this periodic resonant waveguide mode have the same phase over the entire thickness of the core, that is, spatially coherent X-rays. From the end face of the waveguide, the X-ray wavelength and the core structural period The light is emitted with a small divergence angle determined.

  As described above, the X-ray waveguide that enables X-ray propagation in the periodic resonant waveguide mode is configured to confine multiple interference of X-rays caused by the periodic structure by total reflection at the interface between the core and the cladding. Therefore, the X-ray reflectivity at this interface greatly affects the propagation efficiency of the waveguide. Since the wavelength of X-rays is very short, very high flatness is required at the interface between the core and the clad.

  However, the surface of the periodic structure used for the core of the X-ray waveguide of the present invention cannot always guarantee sufficient flatness, and because of this problem, the flatness of the core surface is a problem. Therefore, a new device configuration that enables X-ray propagation in the periodic resonant waveguide mode is required.

  The basic configuration of the X-ray waveguide that enables X-ray propagation in the periodic resonant waveguide mode according to the present invention is as shown in FIG. Depending on the material used, the structure has a relatively large surface roughness. As shown in FIG. 4, when a clad portion is formed thereon, the flatness at the interface 41 between the core portion surface and the clad portion is obtained. May be lower. In such a case, loss due to scattering at the interface increases, and the effect of X-ray confinement by the cladding is reduced. However, when the periodic structure is formed on a clad member having sufficient flatness, the flatness of the interface is ensured at the interface 42 between the bottom surface of the core and the clad, and the entire interface on this side is guaranteed. It is possible to reduce the loss during reflection.

  The difference between the X-ray waveguide of the present invention and the X-ray waveguide enabling the X-ray waveguide by the periodic resonance waveguide mode having the simplest configuration shown in FIG. A plurality of components having a clad portion formed on only one of the periodic structures to be held are held so that the core portions face each other. Hereinafter, description will be made with reference to FIG. 5 which is a schematic diagram of the present invention. As shown in FIG. 5, in the waveguide of the present invention, a core portion 51 made of a periodic structure is formed on a clad portion 52 having a flat surface, and forms a component of the waveguide. As the flatness of the surface of the clad portion 52, it is preferable that the mean square roughness is less than 5 nm in order to reduce the loss in total reflection at the interface between the core portion and the clad portion. Reference numeral 53 denotes a substrate that holds the components of the waveguide composed of the core and the clad, and is used to maintain the mechanical strength of the waveguide. In this figure, the roughness of the surface of the periodic structure forming the core portion is exaggerated. In the X-ray waveguide of the present invention, as shown in the drawing, a plurality of waveguide components are held facing each other with the core portion inside. In this description, a case where there are two components will be described. The base material holding the first component is fixed to the holder 56. The holder 56 may be basically fixed. However, in order to adjust the position with respect to the incident X-ray and the incident angle, the holder 56 is preferably fixed to a movable stage (not shown) capable of controlling the angle and the translational position. On the other hand, the base material holding the second component is fixed to a stage 57 having a mechanism capable of precisely controlling the spatial position. The stage 57 requires high position control resolution and accuracy, and a piezo actuator is preferably used as the driving means. In the X-ray waveguide of the present invention, the positional relationship, that is, the relative position between the first component and the second component is controlled. When the positional relationship between the first component and the movable second component is not controlled, the two periodic structures cause X-ray interference as independent periodic structures, but the periodic resonance guides. X-ray propagation in wave mode cannot be achieved. In order to achieve the periodic resonant waveguide mode, as schematically shown in FIG. 6A, X-rays scattered at the interfaces of different components of the real part of the refractive index of the periodic structure are separated from the core part and the clad part. It is confined in the core part by total internal reflection at the interface, causing multiple interference, and the electric field node corresponds to the low refractive index layer with high electron density and the antinode of electric field to the low and high refractive index layer with low electron density. Such an electric field needs to be formed in the periodic structure. Here, by adjusting the movable stage 57 holding the constituent elements, optimizing the positional relationship between the two constituent elements so that the periodic phases of the respective periodic structures are aligned, the two periodic structures are It functions as if it is one periodic structure, and the electric field as described above can be formed between the clads of the two components as shown in FIG. 6B. In order to make this possible, the periodic periods of the opposing periodic structures need to be the same.

  There is no particular limitation on the interval 55 between the core portions facing each other, but when the interval is about 20 times or more of the structural period, a plurality of X-ray modes propagating in the gap space between the cores are formed. Therefore, it is difficult to select a single periodic resonance waveguide mode. The preferred spacing between the cores of the components is less than 20 times, more preferably less than 10 times the core structural period. Here, the space | interval of the opposing core part of a component refers to the distance between the outermost surfaces of the opposing core part.

  The above description relates to a configuration in which one component is fixed. However, even if a plurality of components are fixed on the movable stage, the positional relationship between the two periodic structures can be adjusted precisely. In this case, the same effect can be obtained.

  As described above, according to the present invention, even when the roughness of the core surface is large to some extent, it is possible to suppress loss due to inevitable scattering when the cladding portion is directly formed on the surface.

  Moreover, although the said description described the case where the number of components was 2, the number of components is not limited to 2. For example, as shown in FIG. 7, it is also possible to manufacture an X-ray waveguide by combining a plurality of such configurations. For example, in FIG. 7, a waveguide component composed of a clad portion having a flat surface and a periodic structure core portion thereon is fixed to three side surfaces of a triangular prism base material having a regular triangular cross section. The other component element fixed on the movable stage is held with the surface on which the core is formed facing each other. Also in this case, in order to control the incident angle and the incident position with respect to the X-ray, it is preferable that the triangular prism base material is fixed to a stage capable of controlling the angle and translation. In this case, a waveguide capable of propagating X-rays in three periodic resonance waveguide modes can be formed. However, if the structural periodicity in these three waveguides is changed, for example, a triangular prism base material will be the center. By switching the three waveguides by rotating the X-rays, it becomes possible to emit X-rays in different directions or to emit X-rays of different wavelengths at the same angle.

  As an interferometer using a plurality of periodic structures, a Bose-Hart X-ray interferometer is known. In this case, in order to make an interference X-ray generated by a plurality of periodic structures (crystals) coherent. The plurality of periodic structures (crystals) used are those cut from a large single crystal. In this case, since the crystal structure period is small and there is no control means with a resolution sufficient to control the positional relationship between two independent crystals so as to provide coherence, the crystal is created from a single crystal. However, since the periodic structure used in the X-ray waveguide according to the present invention has a large structural period, the positional relationship of the independent periodic structures is determined so that each interference X-ray is coherent. It is possible to adjust using a precision position control stage such as a piezo actuator.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the contents of the examples.

Example 1
In this example, two waveguide components, in which a silica mesostructured film prepared using a nonionic surfactant as a structure-directing agent on a tungsten clad formed on a silicon single crystal substrate, are opposed to each other. The first component is fixed with respect to the incident X-ray, and the position of the second component with respect to the first component is precisely controlled by using a stage driven by a piezo actuator, so that periodic resonance induction is achieved. It is an example which enables X-ray propagation by a wave mode.

  Tungsten is deposited in a thickness of 20 nm on the surface of each of the two silicon substrates by sputtering to form a clad region. The surface of the tungsten film has high flatness with a mean square roughness determined by an atomic force microscope of less than 1.0 nm.

  A silica mesostructured film is produced on this. The surfactant used is the nonionic surfactant Pluronic P123. The precursor solution used for the production of the silica mesostructured film was prepared by adding 26.4 ml of 0.01M dilute hydrochloric acid to a solution obtained by dissolving 54.7 ml of tetraethoxysilane (TEOS) in 74.4 ml of ethanol, and A solution B prepared by dissolving 13.7 g of P123 in 49.6 ml of ethanol is mixed, and finally 12.0 ml of pure water is added. The above-mentioned precursor solution is dip-coated on the silicon substrate on which the tungsten film is formed at a pulling rate of 0.5 mm / s and dried at 40 ° C. for 24 hours to obtain a silica mesostructured film.

  It is confirmed from the X-ray diffraction analysis and the X-ray reflectivity measurement that the silica mesostructured film thus produced has a structure period of 10.1 nm and a layer number of 42 layers. Moreover, it becomes clear by electron microscope observation that this film has a two-dimensional hexagonal structure including cylindrical micelles. This periodic structure is the same in the two components. The surface roughness of the silica mesostructured thin film is evaluated by an atomic force microscope, and it becomes clear that the mean square roughness is 11 nm. The two components have a size of 3 mm in the X-ray waveguide direction (Y direction in FIG. 8).

As shown in FIG. 8, one of the two components (first component) 81 is fixed to a holder, and the holder controls the X-ray incident angle and the incident position with respect to the first component. Therefore, ω ₁ and z ₁ are fixed on the movable stage 82.

  As shown in FIG. 9, the other (second component) 91 is fixed on a precision movable stage 92 driven by a piezoelectric actuator. The piezo actuator driving stage uses two angles of ω and ψ shown in FIG. 9 and capable of precise control of z translation. The stage is also preferably capable of in-plane rotation angle φ and translation in the x and y directions, but high resolution is not necessarily required for these axial movements.

First, the first component shown in FIG. 8 fixed on the ω ₁ , z ₁ movable stage by the holder is aligned with the X-ray. In this adjustment, the position z ₁ and the angle ω ₁ are adjusted so that the surface of the periodic structural body of the first component blocks the incident X-ray optical path in parallel with the optical path and the intensity is approximately ½. Do. The X-ray used is MoKα ray and the energy is 17.5 keV.

  From this position, the first component is rotated around the X-ray incident position, and the incident angle is set to the multilayer structure period of 10.1 nm, which is the angle at which X-ray propagation in the periodic resonant waveguide mode occurs. The angle is set to 0.2 °, which is slightly smaller than the corresponding Bragg angle. This angle is smaller than the total reflection critical angle when the same 17.5 keV X-ray is incident on the tungsten layer from the silica mesostructure layer, and the X-ray propagating in the core at this propagation angle is the cladding layer. To be confined in the waveguide.

  The position of the second component is adjusted with respect to the first component whose position is determined in this way. First, the second component fixed to the movable stage is opposed to the first component so that the core surfaces of the first component and the second component are evenly contacted in the coarse motion mode. From this state, the z-axis of the piezo stage is moved by about 20 nm, and the X-ray waveguide is manufactured so that the core surfaces of the first component and the second component are opposed to each other through a minute gap.

  Here, while irradiating the waveguide with X-rays and monitoring the X-rays with a detector, the z-axis of the piezo stage holding the second component so that the transmitted X-ray intensity is maximized, ω Finely adjust the axis and ψ axis. At the position where the transmitted X-ray intensity is maximized, the periodic structures of the first component and the second component have lattice planes that form the periodic structure in parallel, and the period in each periodic structure. The sex phase will match each other.

  Finally, as described above, while irradiating the waveguide with X-rays, the ω axes of these components are synchronized and rotated precisely by a minute angle to determine the incident angle at which the X-ray intensity is maximized. In this case, the X-ray incident angle is as small as about 0.2 °, and the X-ray incident angle is such that it is incident at an angle close to perpendicular to the waveguide end face.

  By observing the far-field image of the X-ray emitted from the waveguide whose position has been adjusted as described above with a two-dimensional X-ray detector, the phase of the X-ray emitted from the waveguide can be changed to that of the waveguide. It is confirmed that they are aligned in the thickness direction.

  According to this example, even when a silica mesostructure whose core surface has a root mean square roughness of more than 10 nm is used for the core, by using the configuration of the present invention, X-ray propagation by a good periodic resonance waveguide mode can be achieved. It can be shown that it can be achieved.

(Example 2)
In this example, two waveguide components in which a boron carbide (B ₄ C) / alumina (Al ₂ O ₃ ) laminated film is formed on a tungsten clad formed on a silicon single crystal substrate are opposed to each other. The first component is fixed with respect to the incident X-ray, and the position of the second component with respect to the first component is precisely controlled by using a stage driven by a piezo actuator, whereby periodic resonance is achieved. This is an example that enables X-ray propagation in a guided mode.

  Tungsten is deposited in a thickness of 20 nm on the surface of each of the two silicon substrates by sputtering to form a clad region. The surface of the tungsten film has high flatness with a mean square roughness determined by an atomic force microscope of less than 1.0 nm.

Further, an alternate laminated film of boron carbide and alumina is formed thereon by sputtering. The film thickness of B ₄ C is 12 nm, the film thickness of Al ₂ O ₃ is 3 nm, the structural period is 15 nm, and the total number is 100 layers. The material in contact with tungsten is Al ₂ O ₃ . By this film forming process, two X-ray waveguide components are created. The surface roughness of the multilayer film is evaluated by an atomic force microscope, and it becomes clear that the root mean square roughness is about 7 nm. These two components have an X-ray waveguide direction size of 4 mm.

As in the first embodiment, one of the two components (first component) is fixed to a holder, and the holder controls the X-ray incident angle and the incident position with respect to the first component. Therefore, ω ₁ and z ₁ are fixed on the movable stage.

  The other (second) component is fixed on a precision movable stage driven by a piezo actuator, as in the first embodiment. The piezo actuator drive stage is the same as that used in the first embodiment.

  First, the first component is aligned with incident X-rays in the same procedure as in the first embodiment. As described in the first embodiment, this adjustment is performed so that the surface of the periodic structure body of the first constituent element blocks the incident X-ray optical path in parallel with the optical path so that the intensity is approximately ½. Adjust and do. The X-ray used is MoKα ray and the energy is 17.5 keV.

  From this position, the first component is rotated around the X-ray incident position, and the incident angle corresponds to the multilayer structure period of 15 nm, which is the angle at which X-ray propagation occurs in the periodic resonant waveguide mode. The angle is set to 0.135 °, which is slightly smaller than the Bragg angle. This angle is smaller than the critical angle of total reflection when the same 17.5 keV X-ray is incident on the tungsten layer from the alumina layer, and the X-ray propagating in the core at this propagation angle is guided by the cladding layer. It is confined in the waveguide.

  The position of the second component is adjusted in the same manner as in the first embodiment with respect to the first component whose position is determined in this way. First, the second component fixed to the movable stage is opposed to the first component, and the core surfaces of the first component and the second component are brought into contact with each other in the coarse motion mode. Subsequently, the z-axis of the piezo stage is moved about 20 nm so that the core surfaces of the first component and the second component face each other with a small gap.

  Here, while irradiating the waveguide with X-rays and monitoring the X-rays with a detector, the z-axis of the piezo stage holding the second component so that the transmitted X-ray intensity is maximized, ω Finely adjust the axis and ψ axis. At the position where the transmitted X-ray intensity is maximized, the periodic structures of the first component and the second component have lattice planes that form the periodic structure in parallel, and the period in each periodic structure. The sex phase will match each other.

  Finally, as described above, while irradiating the waveguide with X-rays, the ω axes of these components are synchronized and rotated precisely by a minute angle to determine the incident angle at which the X-ray intensity is maximized. In this case, the X-ray incident angle is also very small, about 0.14 °, and is arranged so as to be incident at an angle close to perpendicular to the waveguide end face.

  By observing the far-field image of the X-ray emitted from the waveguide whose position has been adjusted as described above with a two-dimensional X-ray detector, the phase of the X-ray emitted from the waveguide can be changed to that of the waveguide. It is confirmed that they are aligned in the thickness direction.

  According to this embodiment, even when a multilayer film having a relatively rough surface with a root mean square roughness of about 7 nm is used for the core, by using the configuration of the present invention, X-ray propagation by a good periodic resonance waveguide mode can be achieved. It can be shown that can be achieved.

(Example 3)
In this example, two waveguide constituent elements are formed by forming a mesoporous silica mesostructured film made of a nonionic surfactant as a structure-directing agent on a tungsten clad formed on a quartz glass substrate. The first component is fixed with respect to the incident X-ray, and the position of the second component with respect to the first component is precisely controlled using a stage driven by a piezo actuator. This is an example that enables X-ray propagation in the resonant waveguide mode.

  Tungsten is deposited in a thickness of 20 nm on each surface of the two quartz glass substrates by sputtering to form a clad region. The surface of the tungsten film has high flatness with a mean square roughness obtained by an atomic force microscope of about 1.8 nm.

  On top of this, the same silica mesostructured film as used in Example 1 is produced in the same procedure as in Example 1. The silica substrate having the tungsten film formed thereon is dip-coated with the precursor solution at a pulling rate of 0.5 mm / s and dried at 50 ° C. for 60 hours to obtain a silica mesostructured film.

  The silica mesostructured film thus prepared is immersed in ethanol to extract and remove the surfactant. The removal of the surfactant is confirmed by the disappearance of the absorption peak due to the C—H bond in the infrared absorption spectrum. It is confirmed by X-ray diffraction analysis and X-ray reflectivity measurement that the mesoporous silica thin film after the surfactant extraction has a structural period of 9.8 nm and 42 layers. Further, it becomes clear by observation with an electron microscope that this film has a two-dimensional hexagonal structure having cylindrical mesopores. The mesoporous silica film having this periodic structure is the same in the two components. The surface roughness of the silica mesostructured thin film is evaluated by an atomic force microscope, and it becomes clear that the root mean square roughness is 12 nm. The two components have a size of 5 mm in the X-ray waveguide direction.

As in the first and second embodiments, one of these two components (first component) is fixed to a holder, and the holder has an X-ray incident angle and an incident position with respect to the first component. Is controlled on the ω ₁ , z ₁ movable stage.

  On the other hand, the second component is fixed on a precision movable stage driven by a piezoelectric actuator. The piezo actuator driving stage is the same as that used in the first and second embodiments.

  First, the first component is aligned with incident X-rays in the same procedure as in the first embodiment. As described in the first embodiment, this adjustment is performed so that the surface of the periodic structure body of the first constituent element blocks the incident X-ray optical path in parallel with the optical path so that the intensity is approximately ½. Adjust and do. The X-ray to be used is CuKα ray, and the energy is 8.0 keV.

  From this position, the first component is rotated around the X-ray incident position, and the incident angle is set to the structural period of the multilayer film of 9.8 nm, which is the angle at which X-ray propagation in the periodic resonant waveguide mode occurs. Set the angle to 0.45 °, which is slightly smaller than the corresponding Bragg angle. This angle is smaller than the total reflection critical angle when X-rays having the same energy of 8 keV are incident on the tungsten layer from the mesoporous silica layer. The X-rays propagating in the core at this propagation angle are caused by the cladding layer. It is confined in the waveguide.

  The position of the second component is adjusted in the same manner as in the first and second embodiments with respect to the first component whose position is determined in this manner. First, the second component fixed to the movable stage is opposed to the first component so that the core surfaces of the first component and the second component are evenly contacted in the coarse motion mode. From this state, the z-axis of the piezo stage is moved by about 20 nm so that the core surfaces of the first component and the second component are opposed to each other through a minute gap.

  Here, while irradiating the waveguide with X-rays and monitoring the X-rays with a detector, the z-axis of the piezo stage holding the second component so that the transmitted X-ray intensity is maximized, ω Finely adjust the axis and ψ axis. At the position where the transmitted X-ray intensity is maximized, the periodic structures of the first component and the second component have lattice planes that form the periodic structure in parallel, and the period in each periodic structure. The sex phase will match each other.

  Finally, as described above, while irradiating the waveguide with X-rays, the ω axes of these components are synchronized and rotated precisely by a minute angle to determine the incident angle at which the X-ray intensity is maximized. In this case, the X-ray incident angle is as small as about 0.45 °.

  By observing the far-field image of the X-ray emitted from the waveguide whose position has been adjusted as described above with a two-dimensional X-ray detector, the phase of the X-ray emitted from the waveguide can be changed to that of the waveguide. It is confirmed that they are aligned in the thickness direction.

  According to this example, even when a mesoporous silica film having a core surface having a root mean square roughness of more than 10 nm is used for the core, by using the configuration of the present invention, X-ray propagation by a good periodic resonance waveguide mode can be achieved. It can be shown that it can be achieved.

  The X-ray waveguide of the present invention is used as an optical element for obtaining a large-diameter X-ray beam having a spatially uniform phase in an X-ray optical technology field such as an X-ray imaging technique and an X-ray exposure technique. Can do.

DESCRIPTION OF SYMBOLS 11 Core part 12, 13 Component which forms a core part 14 Cladding part 15 Base body 51 Core part 52 Cladding part 53 Base 54 Component 55 Space | interval of opposing core part 56 Holder 57 Movable stage

Claims (9)

A plurality of components having a cladding part and a core part in which a plurality of components having different real refractive index parts are periodically arranged on the cladding part face each other with the core part facing inward X A line waveguide,
The periods of the plurality of components of the core portion of the component facing each other are equal,
The total reflection critical angle at the interface between the cladding part and the core part is larger than the Bragg angle corresponding to the structural period of the core part with respect to X-rays having the same wavelength,
And the total reflection critical angle at the interface of a plurality of components having different real part of the refractive index forming the core part is smaller than the Bragg angle,
An X-ray guide comprising means for controlling a positional relationship between at least one first component of the components and a second component facing the first component. Waveguide.   The X-ray waveguide according to claim 1, wherein the means for controlling the positional relationship is a piezo actuator.   The core part of said 1st component and said 2nd component has structure periodicity in the direction perpendicular | vertical with respect to the surface of the said cladding part, The 1st or 2 characterized by the above-mentioned. The described X-ray waveguide.   The core portion of the first component and the second component has a one-dimensional periodic structure in which a plurality of components having different real refractive index portions are periodically stacked. 4. The X-ray waveguide according to any one of 3.   The core part of said 1st component and said 2nd component is an organic-inorganic mesostructure film | membrane, The X as described in any one of Claim 1 thru | or 4 characterized by the above-mentioned. Line waveguide.   The X-ray waveguide according to any one of claims 1 to 4, wherein a core part of the first component and the second component is a mesoporous material film.   6. The X-ray waveguide according to claim 5, wherein the core parts of the first component and the second component are formed by self-assembly of an amphiphilic material. Forming a core part on which a plurality of components having different refractive index real parts are periodically formed on a clad part to produce a component of an X-ray waveguide;
A plurality of the constituent elements having a core portion having the same structural period, and arranging the constituent elements facing each other with the core portion inside, and
Providing a mechanism capable of controlling a positional relationship between at least one first component of the components and a second component facing the first component. A method for manufacturing a featured X-ray waveguide. A plurality of components having a cladding part and a core part in which a plurality of components having different real refractive index parts are periodically formed on the cladding part face each other with the core part facing inward. In the line waveguide,
Controlling the positional relationship between at least one first component of the components and a second component facing the first component with the core portion inward, the periodic structure A method for controlling an X-ray waveguide, characterized by causing X-rays to resonate based on the X-ray waveguide.

Images