WO2013129309A1 - Grille d'absorption pour imagerie radiologique, son procédé de fabrication ainsi que système d'imagerie radiologique - Google Patents

Grille d'absorption pour imagerie radiologique, son procédé de fabrication ainsi que système d'imagerie radiologique Download PDF

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Publication number
WO2013129309A1
WO2013129309A1 PCT/JP2013/054753 JP2013054753W WO2013129309A1 WO 2013129309 A1 WO2013129309 A1 WO 2013129309A1 JP 2013054753 W JP2013054753 W JP 2013054753W WO 2013129309 A1 WO2013129309 A1 WO 2013129309A1
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thin film
grid
substrate
radiation
layer
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PCT/JP2013/054753
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English (en)
Japanese (ja)
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金子　泰久
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富士フイルム株式会社
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    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
    • G21K1/00—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating
    • G21K1/06—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating using diffraction, refraction or reflection, e.g. monochromators

Definitions

  • the present invention relates to an absorption grid for radiographic imaging, a manufacturing method thereof, and a radiographic imaging system using the grid.
  • X-ray When radiation such as X-rays (hereinafter, X-ray is taken as an example) is irradiated on a subject such as a human body, the intensity and phase change due to the interaction with the subject.
  • X-ray imaging apparatuses that are widely used image the transmitted X-ray intensity. For example, since bones and the like have low X-ray transmittance, and tissues such as muscles have high X-ray transmittance, when the distribution of transmitted X-ray intensity is imaged, it is possible to identify tissues having different X-ray transmittances. it can.
  • an X-ray intensity image obtained by imaging the intensity of transmitted X-rays (hereinafter referred to as an X-ray intensity image)
  • a tissue having a high X-ray transmittance is typically black and a tissue having a low X-ray transmittance is white.
  • tissues having different X-ray transmittances can be identified.
  • tissues having similar X-ray transmittances are adjacent to each other, it is not easy to identify them.
  • soft tissues such as cartilage have a high X-ray transmittance
  • tissues and body fluids adjacent to the periphery have a high X-ray transmittance, so that the soft tissue is difficult to be reflected in an X-ray intensity image.
  • lesions also occur in tissues that are difficult to see in an X-ray intensity image, it is desired that these can be identified by X-ray imaging.
  • phase contrast image an X-ray image that can identify a soft tissue having a high X-ray transmittance is obtained by imaging a subject based on a phase change of transmitted X-rays (phase imaging).
  • an X-ray imaging system that performs phase imaging, in order to obtain information on a phase change of transmitted X-rays, at least two grids are arranged between an X-ray source and an X-ray detector to image a subject. . Specifically, the first grid and the second grid are disposed opposite to each other between the X-ray source and the X-ray detector, and the X-rays emitted from the X-ray source are passed through the first grid.
  • An X-ray image having a self-image of one grid is generated. For example, the Talbot effect is used to generate the X-ray image.
  • the X-ray image that has passed through the first grid and the second grid is changed to the X-ray while the position of the second grid is changed stepwise in the in-plane direction.
  • a phase contrast image can be generated based on a plurality of images obtained by photographing. This X-ray image capturing method is called a fringe scanning method.
  • a source grid may be provided between the X-ray source and the first grid to disperse the X-ray focal point and improve the contrast of the X-ray image.
  • the first grid either an absorption grid that partially absorbs X-rays or a phase grid that partially modulates and transmits the phase of X-rays can be used.
  • an absorption grid for the second grid and the source grid it is necessary to use an absorption grid for the second grid and the source grid.
  • the absorption grid needs to have a high aspect ratio.
  • the absorption grid is formed by periodically forming a groove having a high aspect ratio on the surface of a substrate such as silicon and embedding a metal material having a high X-ray absorption such as gold (Au) in the groove.
  • the groove filled with the metal material becomes the X-ray absorbing portion, and the portion of the substrate where the groove is not formed becomes the X transmitting portion.
  • electroplating is used as a method for embedding a metal material almost uniformly in a groove having a high aspect ratio. To perform this electroplating, it is necessary to provide a sheath electrode at least at the bottom of the groove. is there.
  • a groove is previously formed in a low-resistance conductive silicon substrate, and the conductive silicon itself is used as a seed electrode, and a metal serving as an X-ray absorbing portion is electroplated in the formed groove.
  • a method of embedding is also known (see JP 2011-157622 A).
  • a metal thin film is formed on two substrates in order to connect an electroplating current terminal to a sheath electrode, and then an end of one substrate is cut off. By reducing the size, a part of the metal thin film of the other substrate is exposed while the two substrates are joined. In this case, dust or the like generated by excising the substrate may adhere to the joint surface, or may come into contact with the joint surface and cause scratches such as unevenness.
  • Diffusion bonding is a method in which atoms are diffused and bonded between contact surfaces by applying pressure and heating to such an extent that plastic deformation does not occur in the base material substrate. For this reason, the quality of bonding by diffusion bonding is greatly influenced by the flatness and cleanliness of the bonding surface. That is, if there is dust or irregularities on the joint surface, voids or the like are generated and joint failure is likely to occur. Further, even if the joining surfaces are joined with dust or irregularities, they are likely to deteriorate over time, such as peeling with a void or the like as a base point.
  • the metal thin film In order to suppress such bonding defects, it is better to thin the metal thin film to be joined by diffusion bonding. However, if the metal thin film is made too thin, the current density flowing through the metal thin film (seeds electrode) during electroplating will be reduced. By increasing, the seed electrode may be destroyed, and the electroplating may not be performed normally.
  • the metal deposition rate and the amount deposited by electroplating differ in each groove, and the X-ray absorption part may vary.
  • the groove structure itself is damaged due to the difference in the deposition rate and amount of metal between adjacent grooves, and it may not function as a grid.
  • An object of the present invention is to provide an absorptive grid and a method for manufacturing the same that are free from defects due to poor bonding between substrates and differences in the amount of metal deposited during electroplating. It is another object of the present invention to provide a radiation imaging system using this radiation image capturing absorption grid.
  • the absorption grid for radiographic imaging of the present invention includes a grid layer, a support substrate, and a metal layer.
  • the grid layer radiation absorbing portions that absorb radiation and radiation transmitting portions that transmit radiation are alternately arranged in a direction perpendicular to the incident direction of the radiation, and the specific resistance value of the radiation transmitting portion is 1.0 ⁇ 10 3.
  • the support substrate has a grid layer and a low resistance having a specific resistance value greater than 1.0 ⁇ 10 ⁇ 4 ⁇ cm and not greater than 100 ⁇ cm.
  • the metal layer is provided between the grid layer and the support substrate.
  • the metal layer preferably includes a first thin film and a second thin film or a third thin film.
  • the first thin film is a metal thin film that functions as a sheath electrode when the radiation absorbing portion is formed by electroplating.
  • the second thin film is a metal thin film provided between the first thin film and the grid layer, having better adhesion to the radiation transmitting portion than the first thin film.
  • the third thin film is a metal thin film that has better adhesion to the support substrate than the first thin film and is provided between the first thin film and the support substrate.
  • the metal layer preferably has a three-layer structure including a first thin film, a second thin film, and a third thin film.
  • the radiation transmitting part is preferably non-conductive silicon.
  • the specific resistance value of the metal layer is 1.0 ⁇ 10 ⁇ 4 ⁇ cm or less, and the support substrate is preferably a conductive silicon substrate doped with impurities.
  • an insulating film is formed on the surface of the radiation transmitting portion.
  • the metal layer is preferably connected to the radiation absorbing portion by the first thin film.
  • the method for manufacturing a grid for radiographic imaging of the present invention includes a first film forming process, a second film forming process, a bonding process, an etching process, and an electroplating process.
  • a first metal thin film is formed on the surface of the non-conductive first substrate.
  • a second metal thin film is formed on the surface of the conductive second substrate.
  • the bonding step the first metal thin film and the second metal thin film formed on the surfaces of the first substrate and the second substrate face each other and bonded by diffusion bonding.
  • the first substrate is etched to form a radiation transmitting portion that transmits radiation and a groove that becomes a radiation absorbing portion that absorbs radiation.
  • a current terminal is connected to the second substrate, electroplating is performed using a metal layer in which the first metal thin film and the second metal thin film are bonded as a seed electrode, and a metal that becomes a radiation absorbing portion is embedded in the groove.
  • the first metal thin film has a first layer to be in close contact with the first substrate and a second layer formed on the first layer, and the second metal thin film is in close contact with the second substrate. And a third layer formed on the fourth layer, and joining the first substrate and the second substrate in the joining step, It is preferable to form a metal layer having a three-layer structure by integrating the third layer.
  • the radiographic imaging system of the present invention is a radiographic imaging system that generates a phase contrast image by imaging radiation emitted from a radiation source through an absorption grid for radiographic imaging, and is an absorption type for radiographic imaging.
  • the grid includes a grid layer, a support substrate, and a metal layer.
  • radiation absorbing portions that absorb radiation and radiation transmitting portions that transmit radiation are alternately arranged in a direction perpendicular to the incident direction of the radiation, and the specific resistance value of the radiation transmitting portion is 1.0 ⁇ 10 3. High resistance of ⁇ cm or more.
  • the support substrate has a grid layer and a low resistance having a specific resistance value greater than 1.0 ⁇ 10 ⁇ 4 ⁇ cm and not greater than 100 ⁇ cm.
  • the metal layer is provided between the grid layer and the support substrate.
  • the absorption grid for radiographic imaging of the present invention and the method for manufacturing the same make it possible to connect a current terminal to the support substrate during electroplating to form the radiation absorbing portion by making the support substrate conductive, and further, between the support substrate and the grid. Since the metal layer serving as the seed electrode is provided so that the support substrate is not exposed to the plating solution, it is possible to reduce inconveniences due to poor bonding or a difference in the amount of deposited metal.
  • the X-ray imaging system 10 includes an X-ray source 11, a source grid 12, a first grid 13, a second grid 14, and an X-ray along the Z direction that is an X-ray irradiation direction.
  • An image detector 15 is provided.
  • the X-ray source 11 has a rotating anode type X-ray tube (not shown) and a collimator (not shown) for limiting the X-ray irradiation field, and emits X-rays to the subject H.
  • the source grid 12 and the second grid 14 are absorption grids that partially absorb X-rays, and linear X-ray absorption parts and X-ray transmission parts are alternately arranged.
  • the first grid 13 is a phase type grid that generates a predetermined phase difference (for example, ⁇ or ⁇ / 2).
  • Each of the grids 12 to 14 is disposed so as to face the X-ray source 11 in the Z direction, and in each case, a grid line is provided along the X direction.
  • the distance between the first grid 13 and the second grid 14 is set to a Talbot distance, for example.
  • the Talbot distance is a distance at which X-rays that have passed through the first grid 13 generate a self-image of the first grid 13 due to the Talbot effect.
  • the X-ray image detector 15 is a flat panel detector using a semiconductor circuit, and is disposed behind the second grid 14.
  • X-rays radiated from the X-ray source 11 are partially shielded by the X-ray absorption part of the source grid 12, thereby reducing the effective focal size in the Y direction, and arranging many in the Y direction.
  • a line-shaped X-ray is formed.
  • the phase of each line-shaped X-ray changes when passing through the subject H.
  • a fringe image (a self-image of the first grid 13) reflecting the transmission phase information of the subject H determined from the refractive index of the subject H and the transmission optical path length. ) Is formed.
  • the striped image generated by each line-shaped X-ray is projected onto the second grid 14 and overlaps at the position of the second grid 14.
  • the stripe image is intensity-modulated by being partially shielded by the second grid 14.
  • a phase contrast image is generated using a fringe scanning method. That is, the second grid 14 is intermittently moved with respect to the first grid 13, and the X-ray image detector 15 performs imaging by irradiating the subject H with X-rays from the X-ray source 11 while the second grid 14 is stopped. This intermittent movement is performed in the Y direction at a constant scanning pitch obtained by equally dividing the lattice pitch (for example, five divisions).
  • phase differentiation An image is obtained.
  • the phase differential image corresponds to the distribution of the X-ray refraction angle in the subject H.
  • the second grid 14 includes a grid layer 21, a metal layer 22, and a support substrate 23.
  • the grid layer 21 is a layer that has an effective function as an absorption grid, and includes an X-ray absorption part 26 and an X-ray transmission part 27, which are alternately arranged.
  • the X-ray absorption part 26 is a columnar structure provided by extending linearly in the X direction, and is formed of a metal material having X-ray absorption. This metal material may be any material as long as it absorbs incident X-rays and can be formed by electroplating as described later. In the present embodiment, the X-ray absorber 26 is formed of gold (Au).
  • the X-ray transmission part 27 is provided between the X-ray absorption parts 26 and has a columnar plate-like structure provided by extending linearly in the X direction like the X-ray absorption part 26.
  • the X-ray transmission part 27 is formed of a material having X-ray transparency. Since the X-ray transmission part 27 is formed by the remaining part obtained by etching the substrate, the X-ray transmission part 27 is formed of a material having low X-ray absorption ability and easy to etch.
  • the X-ray transmission part 27 is made of silicon. Note that an oxide film 27 a is formed on the surface of the X-ray transmission part 27.
  • the X-ray transmission part 27 is made of high resistance non-conductive silicon.
  • the high resistance means a specific resistance value that does not substantially exhibit conductivity during electroplating and does not function as a sheath electrode. Therefore, the specific resistance value of the X-ray transmission part 27 is extremely large as compared with the specific resistance value of the support substrate 23, and is about the same as the insulator.
  • the specific resistance value of the X-ray transmission part 27 (etching substrate 41) is, for example, 1.0 ⁇ 10 3 ⁇ cm or more.
  • the X-direction width of the X-ray absorption unit 26 and the arrangement pitch of the X-ray absorption unit 26 and the X-ray transmission unit 27 (the total width of the X-ray absorption unit 26 and the X-ray transmission unit 27 in the X direction) 11 and the first grid 13, the distance between the first grid 13 and the second grid 14, the arrangement pitch of the X-ray absorption part and the X-ray transmission part of the first grid 13, and the like.
  • the width of the X-ray absorption part is approximately 2 to 20 ⁇ m
  • the arrangement pitch of the X-ray absorption part and the X-ray transmission part is 4 to 40 ⁇ m, which is twice as large.
  • the thickness of the X-ray absorbing portion in the Z direction is, for example, 100 to 200 ⁇ m in consideration of corneal X-ray vignetting irradiated from the X-ray source 11.
  • the width of the X-ray absorption unit 26 is 2.5 ⁇ m
  • the arrangement pitch of the X-ray absorption unit 26 and the X-ray transmission unit 27 is 5 ⁇ m
  • the thickness of the X-ray absorption unit 26 is 100 ⁇ m. .
  • the metal layer 22 is provided between the grid layer 21 and the support substrate 23, and stably bonds the grid layer 21 and the support substrate 23 together.
  • the metal layer 22 functions as an etch stopper when forming a groove to be the X-ray absorbing portion 26 on the etching substrate 41, and makes the depth of each groove formed uniform.
  • the metal layer 22 functions as a sheath electrode when the X-ray absorbing portion 26 is formed by electroplating.
  • the metal layer 22 is formed with a three-layer structure of a first thin film 31, a second thin film 32, and a third thin film 33 (see FIGS. 3 to 5).
  • the first thin film 31 is a metal thin film that functions as a sheath electrode when the X-ray absorber 26 is formed by electroplating.
  • the second thin film 32 is a metal thin film that stabilizes the bonding between the X-ray transmission part 27 and the metal layer 22, and is formed of a metal that has at least better adhesion to the X-ray transmission part 27 than the first thin film 31.
  • the third thin film 33 is a metal thin film for stabilizing the bonding between the support substrate 23 and the metal layer 22, and is formed of a metal having better adhesion to the support substrate 23 than at least the first thin film 31.
  • the support substrate 23 is a substrate for manufacturing the grid layer 21 and maintaining its structure, and is a low-resistance conductive silicon substrate.
  • the low resistance is a resistance value indicating conductivity that at least functions as a sheath electrode when the X-ray absorbing portion 26 is formed by electroplating.
  • the support substrate 23 is a silicon in which impurities such as phosphorus (P), boron (B), and arsenic (As) are added and the specific resistance value is greater than 1.0 ⁇ 10 ⁇ 4 ⁇ cm and less than or equal to 100 ⁇ cm. It is a substrate.
  • 1.0 ⁇ 10 ⁇ 4 ⁇ cm is the lowest specific resistance value that can theoretically be reached in the silicon substrate.
  • a low-resistance conductive silicon substrate is used as the support substrate 23, but similarly, a low-resistance and conductive gallium arsenide (GaAs) substrate or germanium (Ge) substrate may be used.
  • GaAs gallium arsenide
  • Ge germanium
  • the source grid 12 and the first grid 13 are configured in the same manner as the second grid 14 described above. However, the width of the X-ray absorption unit, the arrangement pitch of the X-ray absorption unit and the X-ray transmission unit, the overall size, and the like are determined by the arrangement of each grid.
  • the second grid 14 is manufactured in approximately six processes including a first film forming process, a second film forming process, a bonding process, an etching process, an oxide film forming process, and an electroplating process.
  • the second grid 14 when the second grid 14 is manufactured, first, the second thin film 32 and the electrode film 31a are formed on one surface of the etching substrate 41 to form the metal layer 22a (first formation). Membrane process).
  • the etching substrate 41 is a substrate that becomes the X-ray transmission part 27 and is a high-resistance non-conductive silicon substrate. For this reason, in the subsequent electroplating process, the X-ray transmissive part 27 formed from the etching substrate 41 is in contact with the metal layer 22, but no current flows through the X-ray transmissive part 27. In other words, the metal is filled between the X-ray transmission parts 27 in the electroplating process, but the metal is not directly deposited on the surface of the X-ray transmission parts 27.
  • the second thin film 32 is formed of, for example, titanium (Ti) having a thickness of about 10 nm on the surface of the etching substrate 41, and has better adhesion to the etching substrate 41 than the electrode film 31a.
  • titanium is used as the second thin film 32.
  • the second thin film 32 may be chromium (Cr), nickel (Ni), titanium, or an alloy containing these metals. Even when these materials are used, it is preferable to set the thickness of the second thin film 32 to about several nanometers to several tens of nanometers in order to suppress X-ray absorption loss.
  • the electrode film 31a is formed on the second thin film 32 and is, for example, a gold (Au) thin film having a thickness of about 50 to 100 nm.
  • the electrode film 31a is joined to an electrode film 31b formed on the support substrate 23 side as will be described later, thereby forming a sheath electrode in the electroplating process.
  • the specific resistance value is 1 ⁇ 10 ⁇ 4 ⁇ cm or less, and the specific resistance value is at least smaller than that of the support substrate 23 which is a semiconductor.
  • gold is used for the electrode film 31a.
  • any material may be used as long as it is resistant to the plating solution and the formation of the X-ray absorption part 26 by electroplating is easy to proceed.
  • platinum Pt
  • nickel Ni
  • titanium Ti
  • chromium Cr
  • silver Ag
  • tantalum Ta
  • tungsten W
  • iridium Ir
  • palladium A metal film such as Pd
  • rhodium Rh
  • gold platinum
  • platinum iridium, palladium, rhodium, or an alloy containing any of these for the electrode film 31a. It is particularly preferable to use platinum.
  • Gold or platinum has a relatively high X-ray absorption ability, but the electrode film 31a (and the first thin film 31 after being joined to an electrode film 31b described later) is formed thin enough to prevent the X-ray absorption from affecting the film. Therefore, there is almost no loss of X-rays.
  • the third thin film 33 and the electrode film 31b are formed on one surface of the support substrate 23 to form the metal layer 22b (second film forming step).
  • the third thin film 33 is formed of, for example, titanium (Ti) having a thickness of about 10 nm, and has better adhesion to the etching substrate 41 than the electrode film 31b.
  • the third thin film 33 is formed of titanium.
  • the support substrate 23 is a silicon substrate, for example, chromium (Cr), nickel (Ni), titanium, or a metal thereof is used in the same manner as the second thin film 32.
  • An alloy containing the third thin film 33 can be used. Even when these materials are used, it is preferable to set the thickness of the third thin film 33 to about several nm to several tens of nm in order to suppress X-ray absorption loss.
  • the electrode film 31b is formed on the third thin film 33 and is, for example, a gold thin film having a thickness of about 50 nm.
  • the electrode film 31b is joined to the electrode film 31a formed on the support substrate 23 side, and becomes a sheath electrode in the electroplating process.
  • the specific resistance value of the electrode film 31b is 1 ⁇ 10 ⁇ 4 ⁇ cm or less, and the specific resistance value is at least smaller than that of the support substrate 23 which is a semiconductor.
  • the electrode film 31b can be formed using the same metal material as the electrode film 31a. However, since the electrode film 31b is bonded to the electrode film 31a by diffusion bonding as will be described later, the electrode film 31b is preferably formed of the same metal species as the electrode film 31a.
  • the second thin film 32 and the third thin film 33 are the same titanium thin film, but different metals may be used. Further, both the electrode film 31a and the electrode film 31b are formed of a gold thin film. However, different metals may be used as long as they can be bonded in the bonding process.
  • the process of forming the metal layer 22a on the etching substrate 41 is the first film formation process
  • the process of forming the metal layer 22b on the support substrate 23 is the second film formation process.
  • the step of forming the metal layer 22b on the support substrate 23 may be performed first, and then the step of forming the metal layer 22b on the etching substrate 41 may be performed.
  • the same material for example, both titanium
  • the same material for example, both gold thin film
  • the metal layers 22a and 22b can be simultaneously formed on the etching substrate 41 and the support substrate 23 by the same film forming apparatus. In this case, the first film forming process and the second film forming process are performed simultaneously.
  • the etching substrate 41 and the support substrate 23 on which the metal layers 22a and 22b are formed are bonded by diffusion bonding (bonding step). Specifically, the etching substrate 41 and the support substrate 23 are brought into contact with the electrode film 31a and the electrode film 31b, pressed and heated, and the atoms of the electrode film 31a and the electrode film 31b are diffused to thereby diffuse the electrode film 31a and the electrode film. 31b is diffusion bonded, and the etching substrate 41 and the support substrate 23 are bonded as a whole. When the electrode film 31 a and the electrode film 31 b are joined, they are integrated into the first thin film 31.
  • the metal layer 22 formed between the etching substrate 41 and the support substrate 23 has a three-layer structure of the second thin film 32, the first thin film 31, and the third thin film 33.
  • the pressure, temperature, and processing time of the bonding process are within the range in which the etching substrate 41, the support substrate 23, and the metal layers 22a and 22b are not plastically deformed or melted, so that the bonding substrate does not cause defective bonding. It is determined according to the material and thickness of the support substrate 23 and the metal layers 22a and 22b.
  • a column plate structure that is an X-ray transmission part 27 and a groove 47 corresponding to the X-ray absorption part 26 are formed in the etching substrate 41 by etching. (Etching process). Specifically, first, a resist is applied to the exposed surface of the etching substrate 41, and this is exposed and developed to form a linear pattern corresponding to the arrangement pitch of the X-ray transmission part 27 and the X-ray absorption part 26. An etching mask is formed. Then, the X-ray transmission part 27 and the groove 47 are formed by performing deep etching using the metal layer 22 as an etch stopper.
  • Bosch process is an etching method using, for example, SF 6 gas for etching silicon (etching substrate 41) and C 4 F 8 gas for forming a protective film.
  • SF 6 gas for etching silicon
  • C 4 F 8 gas for forming a protective film.
  • etching is performed such that the first thin film 31 of the metal layer 22 is exposed at the bottom of the groove 47.
  • the electroplating process if a part of the metal layer 22 is exposed to the bottom of the groove 47, the electroplating can be performed. Therefore, the second thin film 32 may be exposed, but for example, a second film made of titanium.
  • titanium has a higher ionization tendency than gold ions, so that the titanium ions are eluted in the plating solution and contaminate the plating solution.
  • the surface of the second thin film 32 is oxidized when it comes into contact with the atmosphere or a plating solution, but the adhesion between the oxidized second thin film 32 surface and gold deposited by electroplating is not good. For this reason, it is preferable to perform the electroplating after removing the second thin film 32 exposed at the bottom of the groove 47 and exposing the first thin film 32. Since the first thin film 32 is made of gold deposited by electroplating, it has a plating solution resistance and does not oxidize on the surface even when exposed to the atmosphere or the plating solution. Is good.
  • an oxide film 27a is formed on the surface of the X-ray transmission part 27 (oxide film formation process).
  • the X-ray transmission part 27 substantially functions as an insulator in the electroplating process, but by providing the oxide film 27a on the surface of the X-ray transmission part 27, more reliable insulation is ensured.
  • the oxide film 27 a is provided on the surface of the X-ray transmission part 27, but an insulating material other than the oxide film 27 a may be formed on the surface of the X-ray transmission part 27.
  • the oxide film forming process may be omitted, if the oxide film 27a is formed, growth defects and voids can be suppressed in the electroplating process, and the difference in ionization tendency causes the silicon from the X-ray transmission part 27 to silicon. Can be prevented from contaminating the plating solution.
  • the oxide film 27a having a good film quality or the thick oxide film 27a is provided, if the insulating property of the X-ray transmission part 27 in the electroplating process can be secured by the oxide film 27a, the X-ray transmission part 27 (silicon The insulating property of the substrate 41) itself does not necessarily satisfy the above-described condition (specific resistance value of 1.0 ⁇ 10 3 ⁇ cm or more), and it is only required to satisfy the above-described condition including the oxide film 27a.
  • the oxide film 27a After the formation of the oxide film 27a, as shown in FIG. 7, it is immersed in a plating solution, and gold is deposited and filled in the grooves 47 by electroplating to form the X-ray absorbing portion 26 (electroplating step).
  • the cathode of the current terminal is connected to the support substrate 23.
  • the metal layer 22 becomes a sheath electrode and contacts the surface of the metal layer 22 where gold ions (Au + ) contained in the plating solution are exposed.
  • gold (Au) is deposited.
  • the groove 47 is filled with gold from the bottom, and the X-ray absorption part 26 is formed.
  • the 1st thin film 31 is exposed among the metal layers 22 in an etching process as mentioned above, the 1st thin film 31 is a seed electrode more correctly.
  • the plating solution used in the electroplating process is, for example, a cyan gold bath (KAu (CN) 2 ), and the pH is adjusted to 6 to 8 by adding KH 2 PO 4 or KOH as a pH buffer material.
  • the temperature of the plating solution is 25 to 70 ° C.
  • the current density is 0.001 to 1 A / cm 2
  • platinum can be used for the anode 49.
  • the various conditions of this electroplating process are examples, and are arbitrary if the X-ray absorption part 26 can be formed.
  • the metal filling the groove 47 as the X-ray absorber 26 may be a metal other than gold as long as the X-ray can be shielded in consideration of the depth of the groove 47.
  • a low resistance conductive silicon substrate is used for the support substrate 23, and a current terminal is connected to the support substrate 23 in the electroplating process.
  • a non-conductive silicon substrate is used as a support substrate, for example, an end portion of the silicon substrate 41 is formed before the etching substrate 41 and the support substrate 23 that form the X-ray transmission part 27 are joined by the metal layers 22a and 22b.
  • this process is unnecessary. Therefore, since the surface of the electrode films 31a and 31b that are in contact with each other when the etching substrate 41 and the support substrate 23 are bonded does not usually have dust and scratches, bonding defects caused by these do not occur.
  • the metal layer 22 itself functioning as a sheath electrode is thin, the support substrate 23 is thick, conductive, and has a larger specific resistance value than that of the metal (metal layer 22).
  • the local current density is determined not by the thickness of the metal layer 22 but by the conductivity of the support substrate 23. Therefore, although the metal layer 22 itself is thin, there is no problem that the current flowing through the metal layer 22 is locally concentrated and the metal layer 22 is destroyed.
  • grooves 47 are provided in a conductive silicon substrate and the conductive silicon substrate itself is used as a sheath electrode in the electroplating process.
  • the etching substrate 51 is compared with the metal. Since the resistance value of each of the grooves 47 is greatly changed according to the variation ⁇ , a difference occurs in the deposition rate and the deposition amount of the X-ray absorbing material deposited in each groove 47.
  • the X-ray absorbing material is excessively deposited in the groove 47 having a slightly shallow bottom, and in some cases, the X-ray transmitting portion 27 may be inclined and further collapsed.
  • a part of the X-ray transmission part 47 that is inclined as described above is not suitable for use as the second grid 14.
  • the present invention has a metal layer 22 between the support substrate 23 and the etching substrate 41, and the metal layer 22 is not only a sheath electrode in the electroplating process, but is etched in the etching process for forming the groove 47. Also functions as a stopper. For this reason, the depths of the grooves 47 that become the X-ray absorbing portions 26 are made uniform, there is almost no variation in the depths of the grooves 47, and there is no inclination of the X-ray transmitting portions 47 as shown in FIG. .
  • the etching substrate 41 and the support substrate 23 are both the same silicon substrate although there is a difference in conductivity, and their thermal expansion coefficients are almost equal.
  • a difference in expansion coefficient occurs when the etching substrate 41 or the support substrate 23 expands due to heating in the bonding process.
  • the support substrate 23 may be warped, and in some cases, the warped body may be damaged. Moreover, joining itself may become difficult.
  • the use of the X-ray imaging apparatus 10 causes the X-ray absorption unit 26 to absorb X-rays and have heat, thereby causing the etching substrate 41 ( The X-ray transmission part 27) and the support substrate 23 may expand and contract, and the second grid 14 may be warped or cracked.
  • the thermal expansion coefficients of the etching substrate 41 and the support substrate 23 are substantially equal, the occurrence of breakage due to such a temperature change can be suppressed.
  • the conductive silicon substrate 51 itself is used as a seed electrode, silicon is replaced in the plating solution due to the difference in ionization tendency, and the plating solution is contaminated.
  • the layer 22 particularly the first thin film 31
  • the metal layer 22 has a three-layer structure of the second thin film 32, the first thin film 31, and the third thin film 33, the metal layer 22 can be formed of at least the first thin film 31 alone.
  • the second thin film 32 is provided in addition to the first thin film 31, the adhesion between the etching substrate 41 and the X-ray transmission part 27 and the metal layer 22 is improved. Problems such as peeling of the interface of the transmission part 27 can be prevented.
  • the first thin film 33 is provided in addition to the first thin film 31, the adhesion between the metal layer 22 and the support substrate 23 can be improved, and problems such as peeling at this interface can be prevented.
  • the second grid 14 is formed in a flat plate shape and is mounted on the X-ray imaging system 10 in a flat plate shape.
  • the flat grid plate is used. May cause vignetting in the X-rays at the periphery of the grid.
  • the second grid 14 has good adhesion between the metal layer 22 and the X-ray transmission part 27, and the metal layer. Since the bond between the support 22 and the support substrate 23 is strong, it is difficult to be damaged even if it is bent.
  • the second grid 14 is taken as an example, the source grid 12 and its manufacturing method are the same as the above-described second grid 14 and its manufacturing method. The effect is the same.
  • the first grid 13 is a phase type grid
  • the first grid 13 may be an absorption type grid. If any of the radiation source grid 12, the first grid 13, and the second grid 14 uses at least one of the above-mentioned grids, the benefits can be obtained.
  • a silicon substrate is used for the etching substrate 41 and the support substrate 23, a GaAs substrate, a Ge substrate, or the like may be used. Further, it may not be a semiconductor substrate as long as it is X-ray transparent.
  • a substrate made of the same material is used for the etching substrate 41 and the support substrate 23, but a substrate made of a different material may be used for the etching substrate 41 and the support substrate 23.
  • a silicon substrate may be used as the etching substrate 41 and the support substrate 23 may be a gallium arsenide substrate.
  • the etching substrate 41 and the support substrate 23 are both X-ray transparent, the etching substrate 41 functions as an insulator in the electroplating process, and the support substrate 23 needs to have conductivity as described above. is there. Further, different substrates may be used for the etching substrate 41 and the support substrate 23, respectively.
  • both the etching substrate 41 and the support substrate 23 are made of the same material, it is possible to prevent problems due to the difference in the thermal expansion coefficient. Therefore, when the etching substrate 41 and the support substrate 23 are made of different materials. Even so, it is preferable to select materials for the etching substrate 41 and the support substrate 23 so that the difference in thermal expansion coefficient is small.
  • the etching substrate 41 is deepened by the Bosch process to form the groove 47, but the groove 47 may be formed by another etching method.
  • the grooves 47 may be formed by anisotropic wet etching with different etching rates depending on the plane orientation of the silicon single crystal.
  • the subject H is disposed between the X-ray source and the first grid, but the subject H may be disposed between the first grid and the second grid. In this case as well, a phase contrast image is similarly generated.
  • the radiation source grid is provided, but the radiation source grid may be omitted.
  • the present invention is applicable not only to a radiographic imaging system for medical diagnosis but also to other radiographic systems for industrial use and nondestructive inspection.
  • the grid of the present invention can also be applied to a scattered radiation removal grid that removes scattered radiation in X-ray imaging.
  • the present invention can also be applied to a radiographic imaging system that uses gamma rays or the like in addition to X-rays.

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  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Measurement Of Radiation (AREA)
  • Apparatus For Radiation Diagnosis (AREA)

Abstract

　Selon cette invention, une deuxième grille (14) d'absorption comporte: une couche (21) de grille, un substrat (23), ainsi qu'une couche (22) métallique située entre la couche (21) de grille et le substrat (23). Dans la couche (21) de grille, des parties (26) d'absorption des rayons X, lesquelles absorbent les rayons X et des parties (27) de transmission des rayons X, lesquelles absorbent les rayons X, sont disposées face à la direction d'incidence des rayons X, verticalement et en alternance, et les parties (27) de transmission des rayons X sont constituées de matériau non électroconducteur. Le substrat (23) est électroconducteur. Lors de la formation des parties (26) d'absorption des rayons X par électro-placage, une borne électrique est connectée au substrat (23) et la couche métallique (22) fait office d'électrode à gaine.
PCT/JP2013/054753 2012-03-02 2013-02-25 Grille d'absorption pour imagerie radiologique, son procédé de fabrication ainsi que système d'imagerie radiologique WO2013129309A1 (fr)

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JP2012047257A JP2013181917A (ja) 2012-03-02 2012-03-02 放射線画像撮影用吸収型グリッド及びその製造方法、並びに放射線画像撮影システム
JP2012-047257 2012-03-02

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2977992A1 (fr) * 2014-07-24 2016-01-27 Canon Kabushiki Kaisha Structure, procédé de fabrication de celle-ci et interféromètre de talbot

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014006194A (ja) * 2012-06-26 2014-01-16 Canon Inc 構造体の製造方法
JP7059545B2 (ja) * 2017-09-20 2022-04-26 大日本印刷株式会社 構造体の製造方法、および構造体
DE102022104180A1 (de) * 2022-02-22 2023-08-24 Schott Ag Abschirmmaske für ionisierende Streustrahlung und Verfahren zu dessen Herstellung

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011157622A (ja) * 2010-01-08 2011-08-18 Canon Inc 微細構造体の製造方法
WO2012008118A1 (fr) * 2010-07-15 2012-01-19 コニカミノルタエムジー株式会社 Procédé de fabrication d'un treillis métallique, et treillis métallique
WO2012008120A1 (fr) * 2010-07-15 2012-01-19 コニカミノルタエムジー株式会社 Procédé de fabrication d'une grille métallique, et grille métallique
WO2012026223A1 (fr) * 2010-08-25 2012-03-01 富士フイルム株式会社 Grille de capture d'image de rayonnement, son procédé de fabrication, et système de capture d'image de rayonnement

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011157622A (ja) * 2010-01-08 2011-08-18 Canon Inc 微細構造体の製造方法
WO2012008118A1 (fr) * 2010-07-15 2012-01-19 コニカミノルタエムジー株式会社 Procédé de fabrication d'un treillis métallique, et treillis métallique
WO2012008120A1 (fr) * 2010-07-15 2012-01-19 コニカミノルタエムジー株式会社 Procédé de fabrication d'une grille métallique, et grille métallique
WO2012026223A1 (fr) * 2010-08-25 2012-03-01 富士フイルム株式会社 Grille de capture d'image de rayonnement, son procédé de fabrication, et système de capture d'image de rayonnement

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2977992A1 (fr) * 2014-07-24 2016-01-27 Canon Kabushiki Kaisha Structure, procédé de fabrication de celle-ci et interféromètre de talbot
US10045753B2 (en) 2014-07-24 2018-08-14 Canon Kabushiki Kaisha Structure, method for manufacturing the same, and talbot interferometer
CN109920577A (zh) * 2014-07-24 2019-06-21 佳能株式会社 结构体、其制造方法和塔尔博干涉仪
EP3614398A1 (fr) * 2014-07-24 2020-02-26 Canon Kabushiki Kaisha Structure, son procédé de fabrication et interféromètre de talbot
CN109920577B (zh) * 2014-07-24 2024-01-19 佳能株式会社 结构体、其制造方法和塔尔博干涉仪

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