Radiation detection module and radiation detector

Abstract

A radiation detection module and a radiation detector are provided, which can suppress the occurrence of local stress on a scintillator. The radiation detection module of the embodiment includes: an array substrate, the array substrate has a plurality of photoelectric conversion parts; a scintillator, the scintillator is arranged on the plurality of photoelectric conversion parts; a moisture-proof part, the moisture-proof part covers the top of the scintillator and has a receiving part for receiving a local convex part of the upper end of the scintillator.

Description

Technical Field

[0001] Embodiments of the present invention relate to a radiation detection module and a radiation detector. Background Art

[0002] As an example of a radiation detector, there is an X-ray detector. The X-ray detector is provided with a scintillator and an array substrate. The scintillator converts X-rays into fluorescence, and the array substrate converts the fluorescence into an electrical signal. In addition, in order to improve the utilization efficiency of the fluorescence and improve the sensitivity characteristics, a reflective layer is sometimes provided on the scintillator.

[0003] In addition, in order to suppress the degradation of characteristics due to water vapor, etc., it is necessary to isolate the scintillator and the reflective layer from the external environment. For example, when the scintillator includes CsI (cesium iodide), Tl (thallium) or CsI, Na (sodium), etc., the degradation of characteristics due to water vapor, etc. may be aggravated. Therefore, a moisture-proof portion covering the scintillator and the reflective layer is also provided in the X-ray detector.

[0004] Here, there is a case where the X-ray detector is placed in an environment where the air pressure is reduced to a lower pressure than the atmospheric pressure. Therefore, if there is a gas such as air inside the space defined by the moisture-proof portion, when the X-ray detector is placed in an environment where the air pressure is reduced to a lower pressure than the atmospheric pressure, the moisture-proof portion may be damaged due to expansion of the gas. Therefore, the pressure inside the space defined by the moisture-proof portion becomes lower than the atmospheric pressure.

[0005] In addition, there are cases where a convex portion is locally generated at the upper end of the scintillator or the upper end of the reflective layer. For example, when the scintillator is formed by vacuum evaporation, there are cases where a high crystal is locally formed. In addition, when the reflective layer is formed, the thickness of the reflective layer is locally thickened due to the mixing of impurities or foreign matter, etc., and sometimes a convex portion is locally generated.

[0006] The pressure inside the space defined by the moisture-proof part is lower than the atmospheric pressure, so the moisture-proof part is pressed toward the scintillator under the action of the atmospheric pressure. Therefore, if there is a local convex part on the upper end of the scintillator or the upper end of the reflective layer, the convex part is pressed and local stress is easily generated in the scintillator.

[0007] Therefore, it is desired to develop a technology that can suppress the generation of local stress in the scintillator.

[0008] Prior art literature

[0009] Patent Literature

[0010] Patent Document 1: Japanese Patent Application Publication No. 2009-128023 Summary of the invention

[0011] Technical problem to be solved by the invention

[0012] The technical problem to be solved by the present invention is to provide a radiation detection module and a radiation detector capable of suppressing the occurrence of local stress in a scintillator.

[0013] Technical solutions adopted to solve technical problems

[0014] The radiation detection module of the embodiment includes: an array substrate, the array substrate has a plurality of photoelectric conversion parts; a scintillator, the scintillator is arranged on the plurality of photoelectric conversion parts; and a moisture-proof part, the moisture-proof part covers the top of the scintillator and has a receiving part for receiving a local protrusion at the upper end of the scintillator. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic perspective view for illustrating the X-ray detector and the X-ray detection module according to the present embodiment.

[0016] Figure 2 It is a schematic cross-sectional view for illustrating an X-ray detection module.

[0017] Figure 3 is a block diagram of an X-ray detector.

[0018] Figure 4 (a) and (b) are schematic cross-sectional views for illustrating an X-ray detection module in a comparative example.

[0019] Figure 5 This is a schematic cross-sectional view for illustrating an X-ray detection module according to another embodiment.

[0020] Figure 6 This is a schematic cross-sectional view for illustrating an X-ray detection module according to still another embodiment.

[0021] Explanation of symbols

[0022] 1X-ray detector; 2array substrate; 2a substrate; 2b photoelectric conversion unit; 5scintillator; 5b upper end; 5b1 convex portion; 6reflective layer; 6a convex portion; 7 moisture-proof portion; 7a receiving portion; 8 sealing portion; 10X-ray detection module; 10a X-ray detection module; 10b X-ray detection module; 11 circuit substrate. DETAILED DESCRIPTION

[0023] Hereinafter, the embodiments will be described with reference to the accompanying drawings. In addition, in each of the drawings, the same components are denoted by the same reference numerals, and detailed descriptions thereof will be appropriately omitted.

[0024] In addition, the radiation detector of the embodiment of the present invention can be applied to various radiations such as gamma rays in addition to X-rays. Here, as an example, the case of X-rays, which are representative rays among radiations, is described. Therefore, by replacing "X-rays" in the following embodiments with "other radiations", the radiation detector can also be applied to other radiations.

[0025] Furthermore, the radiation detector can be used, for example, in general medicine, etc. However, the use of the radiation detector is not limited to general medicine.

[0026] Figure 1 It is a schematic perspective view for illustrating the X-ray detector 1 and the X-ray detection module 10 according to the present embodiment.

[0027] In order to avoid complexity, Figure 1 In the figure, the protective layer 2f, the reflective layer 6, the moisture-proof portion 7, the sealing portion 8, etc. are omitted.

[0028] Figure 2 It is a schematic cross-sectional view for illustrating the X-ray detection module 10 .

[0029] Figure 3 is a block diagram of the X-ray detector 1 .

[0030] like Figure 1 and Figure 2 As shown, an X-ray detection module 10 and a circuit substrate 11 are provided in the X-ray detector 1. In addition, a housing (not shown) can be provided in the X-ray detector 1. The X-ray detection module 10 and the circuit substrate 11 can be provided inside the housing. For example, a plate-shaped support plate 12 can be provided inside the housing, the X-ray detection module 10 can be provided on the surface of the support plate 12 on the incident side of the X-rays, and the circuit substrate 11 can be provided on the surface of the support plate 12 on the opposite side of the incident side of the X-rays.

[0031] The X-ray detection module 10 can be provided with an array substrate 2 , a scintillator 5 , a reflective layer 6 , a moisture-proof portion 7 , and a sealing portion 8 .

[0032] The array substrate 2 may include a substrate 2a, a photoelectric conversion unit 2b, a control line (or gate line) 2c1, a data line (or signal line) 2c2, a wiring pad 2d1, a wiring pad 2d2, and a protective layer 2f.

[0033] In addition, the number of photoelectric conversion parts 2b, control lines 2c1, and data lines 2c2 is not limited to the number shown as an example.

[0034] The substrate 2a may be plate-shaped and made of glass such as alkali-free glass. The planar shape of the substrate 2a may be a quadrangle. The thickness of the substrate 2a may be, for example, about 0.7 mm.

[0035] A plurality of photoelectric conversion parts 2b are provided on one surface side of the substrate 2a.

[0036] The photoelectric converter 2b may be rectangular and provided in a region defined by the control line 2c1 and the data line 2c2. A plurality of photoelectric converters 2b may be arranged in a matrix. In addition, one photoelectric converter 2b corresponds to one pixel of an X-ray image.

[0037] A photoelectric conversion element 2b1 and a thin film transistor (TFT; Thin Fil Transistor) 2b2 which is a switching element can be provided in each of the plurality of photoelectric conversion sections 2b.

[0038] In addition, a storage capacitor 2b3 can be provided, which stores the signal charge converted in the photoelectric conversion element 2b1. The storage capacitor 2b3 can be, for example, in the form of a rectangular plate, and is provided under each thin film transistor 2b2. However, depending on the capacity of the photoelectric conversion element 2b1, the photoelectric conversion element 2b1 can also serve as the storage capacitor 2b3.

[0039] The photoelectric conversion element 2 b 1 can be provided as a photodiode or the like, for example.

[0040] The thin film transistor 2b2 switches between storing charge in the storage capacitor 2b3 and releasing charge from the storage capacitor 2b3. The thin film transistor 2b2 may have a gate electrode, a drain electrode, and a source electrode. The gate electrode of the thin film transistor 2b2 can be electrically connected to the corresponding control line 2c1. The drain electrode of the thin film transistor 2b2 can be electrically connected to the corresponding data line 2c2. The source electrode of the thin film transistor 2b2 can be electrically connected to the corresponding photoelectric conversion element 2b1 and the storage capacitor 2b3. In addition, the anode side of the photoelectric conversion element 2b1 and the storage capacitor 2b3 can be grounded. In addition, the anode side of the photoelectric conversion element 2b1 and the storage capacitor 2b3 can also be connected to the bias line.

[0041] A plurality of control lines 2c1 can be provided in parallel with each other at a predetermined interval. The control lines 2c1 extend, for example, in the row direction. One control line 2c1 can be electrically connected to one of a plurality of wiring pads 2d1 provided near the periphery of the substrate 2a. One of a plurality of wiring lines provided on the flexible printed substrate 2e1 can be electrically connected to one wiring pad 2d1. The other ends of the plurality of wiring lines provided on the flexible printed substrate 2e1 can be electrically connected to the readout circuit 11a provided on the circuit substrate 11, respectively.

[0042] A plurality of data lines 2c2 can be provided in parallel with each other at predetermined intervals. The data lines 2c2 extend, for example, in a column direction perpendicular to the row direction. One data line 2c2 can be electrically connected to one of a plurality of wiring pads 2d2 provided near the periphery of the substrate 2a. One of a plurality of wiring lines provided on the flexible printed substrate 2e2 can be electrically connected to a wiring pad 2d2. The other ends of the plurality of wiring lines provided on the flexible printed substrate 2e2 can be electrically connected to the signal detection circuit 11b provided on the circuit substrate 11, respectively.

[0043] The control line 2c1 and the data line 2c2 can be formed using a low-resistance metal such as aluminum or chromium.

[0044] The protective layer 2f can cover the photoelectric conversion unit 2b, the control line 2c1, and the data line 2c2. The protective layer 2f can be formed of an insulating material. For example, the insulating material can be an oxide insulating material, a nitride insulating material, an oxynitride insulating material, or a resin.

[0045] The scintillator 5 is provided on the plurality of photoelectric converters 2b and converts incident X-rays into visible light, ie, fluorescence. The scintillator 5 can be provided so as to cover the region (effective pixel region A) on the substrate 2a where the plurality of photoelectric converters 2b are provided.

[0046] The scintillator 5 may include, for example, cesium iodide (CsI); thallium (Tl), sodium iodide (NaI); thallium (Tl), or cesium bromide (CsBr); europium (Eu), etc. The scintillator 5 may be formed by vacuum deposition. If the scintillator 5 is formed by vacuum deposition, a scintillator 5 composed of a plurality of columnar crystals is formed. The thickness of the scintillator 5 may be, for example, about 600 μm.

[0047] In addition, when the scintillator 5 is formed by vacuum evaporation, a mask having an opening is used. In this case, the scintillator 5 is formed at a position opposite to the opening on the array substrate 2 (above the effective pixel area A). In addition, the film formed by evaporation is also formed on the surface of the mask. In addition, near the opening of the mask, the film grows in a manner that gradually extends into the inside of the opening. If the film extends into the inside of the opening, then, near the opening, evaporation onto the array substrate 2 is suppressed. Therefore, if Figure 1 and Figure 2 As shown, the thickness of the scintillator 5 near the periphery gradually decreases toward the outside.

[0048] In addition, the scintillator 5 can also be formed using, for example, terbium-activated gadolinium sulfate (Gd2O2S / Tb or GOS, Japanese: Terbium-activated sulfated gadolinium sulfate). In this case, a matrix of grooves can be provided in each of the plurality of photoelectric conversion units 2b in the form of a quadrangular prism-shaped scintillator 5.

[0049] The reflective layer 6 can be provided to improve the utilization efficiency of the fluorescence and improve the sensitivity characteristics. That is, the reflective layer 6 is provided to reflect the light of the fluorescence generated in the scintillator 5 that is directed to the side opposite to the side where the photoelectric conversion unit 2b is provided and direct it to the photoelectric conversion unit 2b. However, the reflective layer 6 is not necessarily required, and it can be provided according to the sensitivity characteristics required by the X-ray detection module 10.

[0050] Hereinafter, a case where the reflective layer 6 is provided will be described as an example.

[0051] The reflective layer 6 is disposed on the scintillator 5. The reflective layer 6 is disposed between the upper end 5b of the scintillator 5 and the moisture-proof portion 7. The reflective layer 6 covers at least the upper end 5b of the scintillator 5. The reflective layer 6 can further cover the side end 5a of the scintillator 5.

[0052] For example, a material obtained by mixing light scattering particles made of titanium oxide (TiO 2 ) or the like, a resin, and a solvent can be applied onto the scintillator 5 and dried to form the reflective layer 6 .

[0053] Furthermore, the reflective layer 6 can be formed by, for example, forming a layer made of a metal having a high light reflectivity, such as a silver alloy or aluminum, on the scintillator 5 .

[0054] The moisture-proof portion 7 can be provided to suppress the degradation of the characteristics of the reflective layer 6 and the characteristics of the scintillator 5 due to moisture contained in the air. The moisture-proof portion 7 can cover the upper portion of the scintillator 5 and the upper portion of the reflective layer 6 .

[0055] Here, in the scintillator 5 including a plurality of columnar crystals, there are voids of about 10% to 40% of the volume thereof. In addition, there is a case where the X-ray detector 1 is placed in an environment where the air pressure is reduced to a pressure lower than the atmospheric pressure, such as when transported by airplane or the like. In this case, if there is a gas such as air in the voids of the scintillator 5, then when the X-ray detector 1 is placed in an environment where the air pressure is reduced to a pressure lower than the atmospheric pressure, there is a possibility that the moisture-proof portion 7 may be damaged due to expansion of the gas. Therefore, in the X-ray detector 1, the pressure inside the space defined by the moisture-proof portion 7 becomes lower than the atmospheric pressure. For example, by joining the moisture-proof portion 7 to the sealing portion 8 in an environment where the air pressure is reduced to a pressure lower than the atmospheric pressure, the pressure inside the space defined by the moisture-proof portion 7 can be made lower than the atmospheric pressure.

[0056] In addition, there are cases where there are bubbles or voids inside the sealing part 8, there are cases where there is a gap or leakage path between the sealing part 8 and the moisture-proof part 7, and there are cases where there is a gap or leakage path between the sealing part 8 and the array substrate 2. In the above case, when the moisture-proof part 7 and the sealing part 8 are joined in an environment where the air pressure is reduced to an environment lower than the atmospheric pressure and then returned to the atmospheric pressure environment, atmospheric air will enter the interior through the gap or leakage path. If atmospheric air enters the interior, the moisture-proof part 7 and the scintillator 5 will not be tightly attached, so that wrinkles will be generated on the surface of the moisture-proof part 7, and the tension will disappear. Therefore, it is easy to visually detect the existence of a gap or leakage path. The life of a product with a gap or leakage path may be shortened, but in the process of inspecting such a product, such a product can be easily found and removed. Therefore, it is easy to improve the quality of the X-ray detector 1.

[0057] The moisture-proof part 7 can be, for example, a sheet material containing metal. The metal can be, for example, aluminum-containing metal, copper-containing metal, magnesium-containing metal, tungsten-containing metal, stainless steel, kovar material, etc. In this case, if the moisture-proof part 7 containing metal is provided, the moisture that passes through the moisture-proof part 7 can be completely eliminated.

[0058] Furthermore, the moisture-proof portion 7 may be a laminated sheet in which at least two of a resin film, a metal film, and a resin film are laminated.

[0059] The resin film may be formed of, for example, polyimide resin, epoxy resin, polyethylene terephthalate resin, Teflon (registered trademark), low-density polyethylene, high-density polyethylene, elastic rubber, etc. The metal film may be, for example, a metal film containing the above metals. The metal film may be formed, for example, by sputtering, lamination, etc. The inorganic film may be, for example, a film containing silicon oxide, aluminum oxide, etc. The inorganic film may be formed, for example, by sputtering, etc.

[0060] In this case, the metal film is preferably provided on the side of the scintillator 5. In this way, the metal film can be covered by the resin film or the inorganic film, so it is possible to suppress the metal film from being damaged by external force, etc. In addition, if the metal film is provided on the inner side (on the side of the scintillator 5) than the resin film, it is possible to suppress the deterioration of the characteristics of the scintillator 5 due to the penetration of water through the resin layer.

[0061] Generally speaking, since the linear expansion coefficient of resin is greater than that of metal, if the thickness of the resin film is excessively increased, the array substrate 2 is easily warped due to thermal stress. Therefore, in the case of a laminated sheet including a metal film and a resin film, the thickness of the resin film is preferably set to be less than the thickness of the metal film.

[0062] In addition, the thickness of the moisture-proof part 7 can be determined by considering the absorption of X-rays or rigidity, etc. In this case, if the thickness of the moisture-proof part 7 is increased, the amount of X-rays absorbed by the moisture-proof part 7 increases. On the other hand, if the thickness of the moisture-proof part 7 is reduced, the rigidity decreases and it is easy to be damaged.

[0063] For example, if the thickness of the moisture-proof portion 7 is set to be less than 10 μm, the rigidity of the moisture-proof portion 7 becomes too low, and pinholes may be generated due to damage caused by external forces, thereby possibly causing leakage. If the thickness of the moisture-proof portion 7 is greater than 50 μm, the rigidity of the moisture-proof portion 7 becomes too high, and it is not easy to relieve the thermal stress caused by deformation, and the array substrate 2 is prone to warping. In addition, it may become difficult to confirm the above-mentioned gap and leakage path. Therefore, the thickness of the moisture-proof portion 7 is preferably greater than 10 μm and less than 50 μm.

[0064] For example, the moisture-proof portion 7 may be an aluminum foil having a thickness of 10 μm or more and 50 μm or less. If the thickness of the aluminum foil is 10 μm or more and 50 μm or less, the amount of X-ray transmission can be increased by about 20% to 30% compared to an aluminum foil having a thickness of 100 μm. In addition, if an aluminum foil having a thickness of 10 μm or more and 50 μm or less is used, the occurrence of the above-mentioned leakage can be suppressed, and the confirmation of the above-mentioned gap and leakage path becomes easy. In addition, the warping of the array substrate 2 caused by thermal stress can be suppressed.

[0065] Here, if a large amount of X-rays are irradiated to the human body, it will have an adverse effect on health, so it is necessary to suppress the amount of X-rays irradiated to the human body to the required minimum. Therefore, in the case of the X-ray detector 1 used for medical treatment, the intensity of the irradiated X-rays may be small, and the intensity of the X-rays passing through the moisture-proof part 7 may be very small. Since the moisture-proof part 7 of this embodiment is set as a sheet with a thickness of 10 μm or more and 50 μm or less, it is possible to capture X-ray images even when the intensity of the irradiated X-rays is small.

[0066] Furthermore, if the thickness of the moisture-proof portion 7 is reduced, the rigidity of the moisture-proof portion 7 is reduced. Therefore, if a flange portion or the like is provided to form a three-dimensional moisture-proof portion, cracks are likely to occur when, for example, the metal foil is press-formed. Figure 2 As shown, the periphery of the sheet-shaped moisture-proof portion 7 is bonded to the outer surface 8a of the sealing portion 8. Therefore, it is not necessary to process the moisture-proof portion 7 into a three-dimensional shape in advance, and the sheet-shaped moisture-proof portion 7 can be directly bonded to the outer surface 8a of the sealing portion 8. As a result, even if the thickness of the moisture-proof portion 7 is set to be 10 μm or more and 50 μm or less, it is possible to suppress the occurrence of cracks in the moisture-proof portion 7.

[0067] In addition, the periphery of the moisture-proof part 7 can be joined to the sealing part 8 by heating the periphery of the moisture-proof part 7. In this case, if the temperature near the periphery of the moisture-proof part 7 and the temperature of the sealing part 8 are reduced, thermal stress is generated between the periphery of the moisture-proof part 7 and the sealing part 8. If thermal stress is generated between the periphery of the moisture-proof part 7 and the sealing part 8, peeling may be generated between the periphery of the moisture-proof part 7 and the sealing part 8. If peeling occurs, the moisture-proof performance may be significantly reduced. Since the thickness of the moisture-proof part 7 is more than 10μm and less than 50μm, the moisture-proof part 7 becomes easy to extend when thermal stress is generated. Therefore, since the thermal stress can be relieved, the situation of peeling between the periphery of the moisture-proof part 7 and the sealing part 8 can be suppressed.

[0068] like Figure 2 As shown, the sealing portion 8 is bonded to the side end 5a of the scintillator 5 and the array substrate 2. In this case, the sealing portion 8 can be in close contact with the side end 5a of the scintillator 5. In the case where the scintillator 5 is constituted as an aggregate of a plurality of columnar crystals, a concave-convex portion is formed at the side end 5a of the scintillator 5. If a portion of the sealing portion 8 is disposed inside the concave-convex portion of the side end 5a of the scintillator 5, the bonding strength between the sealing portion 8 and the scintillator 5 can be increased. The sealing portion 8 can be in close contact with the array substrate 2. If the sealing portion 8 is in close contact with the array substrate 2, it is possible to suppress the moisture contained in the atmosphere from penetrating between the sealing portion 8 and the array substrate 2 and reaching the scintillator 5.

[0069] The shape of the outer surface 8a of the sealing portion 8 can be set to a curved surface protruding outward. In this way, the distance L between the outer surface 8a of the sealing portion 8 and the side end 5a of the scintillator 5 can be increased. Therefore, it is possible to suppress the moisture contained in the atmosphere from penetrating the inside of the sealing portion 8 and reaching the scintillator 5.

[0070] Furthermore, if the shape of the outer surface 8a of the sealing portion 8 is formed as a curved surface protruding outward, it is easy to make the vicinity of the peripheral edge of the moisture-proof portion 7 follow the outer surface 8a of the sealing portion 8. Therefore, it is easy to make the moisture-proof portion 7 and the sealing portion 8 close to each other. In addition, since the moisture-proof portion 7 can be deformed smoothly, even if the thickness of the moisture-proof portion 7 is reduced, it is possible to suppress the occurrence of cracks in the moisture-proof portion 7.

[0071] In addition, the height of the sealing portion 8 is preferably set to be less than the height of the scintillator 5. If the height of the sealing portion 8 is configured to be less than the height of the scintillator 5, the sheet constituting the moisture-proof portion 7 can be prevented from being excessively deformed, thereby suppressing the moisture-proof portion 7 from wrinkling, breaking, pinholes, and the like.

[0072] The sealing part 8 contains a thermoplastic resin as a main component. If the sealing part 8 contains a thermoplastic resin as a main component, the sealing part 8 can be bonded to the array substrate 2, the scintillator 5 and the moisture-proof part 7 by heating. Here, for example, if the sealing part 8 contains an ultraviolet curing resin as a main component, it is necessary to irradiate ultraviolet rays when bonding the sealing part 8 to the array substrate 2, the scintillator 5 and the moisture-proof part 7. However, since the moisture-proof part 7 contains metal and the like, it is impossible to transmit ultraviolet rays. In addition, if the moisture-proof part 7 is set to be able to transmit ultraviolet rays, then under the action of ultraviolet rays, the scintillator 5 may change color and the generated fluorescence may be absorbed.

[0073] In contrast, since the sealing portion 8 contains a thermoplastic resin as a main component, it can be easily joined by heating. In addition, the scintillator 5 will not change color under the action of ultraviolet rays. In addition, since the time required for heating and cooling the sealing portion 8 can be short, the manufacturing time can be shortened and the manufacturing cost can be reduced.

[0074] Thermoplastic resins may be, for example, nylon, PET (polyethylene terephthalate), polyurethane, polyester, polyvinyl chloride, ABS (acrylonitrile butadiene styrene), acrylic, polystyrene, polyethylene, polypropylene, etc. In this case, the water vapor permeability coefficient of polyethylene is 0.068 g·mm / day·m 2 The water vapor permeability coefficient of polypropylene is 0.04g·mm / day·m 2. Therefore, if the sealing portion 8 contains any one of polyethylene and polypropylene as a main component, the amount of water that permeates through the inside of the sealing portion 8 and reaches the scintillator 5 can be significantly reduced.

[0075] In addition, the sealing portion 8 may also include a filler using an inorganic material. If a filler using an inorganic material is included in the sealing portion 8, the penetration of moisture can be further suppressed. The inorganic material may be, for example, talc, graphite, mica, kaolin (clay whose main component is kaolinite), etc. The filler may have, for example, a flat shape. By using a filler using an inorganic material, the diffusion of moisture entering the interior of the sealing portion 8 from the outside is prevented, and the speed at which moisture passes through the sealing portion 8 can be reduced. Therefore, the amount of moisture reaching the scintillator 5 can be reduced.

[0076] In addition, it is preferred that at least the outer surface 8a of the sealing portion 8 has water resistance. If the outer surface 8a of the sealing portion 8 has water resistance, it is possible to suppress the entry of moisture into the interior of the sealing portion 8. For example, a water-repellent agent can be applied to the outer surface 8a of the sealing portion 8. In addition, if the sealing portion 8 contains at least one of polyethylene and polypropylene as a main component, it is possible to provide a water-resistant sealing portion 8.

[0077] like Figure 1As shown, the circuit substrate 11 can be disposed on the side of the array substrate 2 opposite to the side where the scintillator 5 is disposed. The circuit substrate 11 can be electrically connected to the X-ray detection module 10 (array substrate 2).

[0078] like Figure 3 As shown, the readout circuit 11a and the signal detection circuit 11b can be provided on the circuit substrate 11. In addition, the above circuits can be provided on one substrate, or can be provided separately on a plurality of substrates.

[0079] The readout circuit 11a switches the thin film transistor 2b2 between an on state and an off state. The readout circuit 11a may include a plurality of gate drivers 11aa and a row selection circuit 11ab.

[0080] The control signal S1 is input to the row selection circuit 11ab from the image processing unit or the like provided outside the X-ray detector 1. The row selection circuit 11ab inputs the control signal S1 to the corresponding gate driver 11aa according to the scanning direction of the X-ray image. The gate driver 11aa inputs the control signal S1 to the corresponding control line 2c1.

[0081] For example, the readout circuit 11a sequentially inputs the control signal S1 to each of the control lines 2c1 through the flexible printed circuit board 2e1. The thin film transistor 2b2 is turned on by the control signal S1 input to the control line 2c1 and can receive the charge (image data signal S2) from the storage capacitor.

[0082] The signal detection circuit 11 b may include a plurality of integrating amplifiers 11 ba , a plurality of selection circuits 11 bb , and a plurality of AD converters 11 bc .

[0083] One integrating amplifier 11ba is electrically connected to one data line 2c2. The integrating amplifier 11ba sequentially receives the image data signal S2 from the photoelectric conversion unit 2b. In addition, the integrating amplifier 11ba integrates the current flowing in a certain time and outputs a voltage corresponding to the integrated value to the selection circuit 11bb. In this way, the value (charge amount) of the current flowing in the data line 2c2 in a predetermined time can be converted into a voltage value. That is, the integrating amplifier 11ba converts the image data information corresponding to the intensity distribution of the fluorescence generated in the scintillator 5 into potential information.

[0084] The selection circuit 11bb selects the integrating amplifier 11ba for reading, and sequentially reads out the image data signal S2 converted into potential information.

[0085] The AD converter 11bc sequentially converts the read image data signal S2 into a digital signal. The image data signal S2 converted into a digital signal can be input to an image processing unit provided outside the X-ray detector 1 through wiring. In addition, the image data signal S2 converted into a digital signal can also be sent to the image processing unit wirelessly.

[0086] The image processing unit forms an X-ray image based on the image data signal S2 converted into a digital signal. In addition, the image processing unit can also be integrated with the circuit board 11.

[0087] Next, the moisture-proof portion 7 will be further described.

[0088] Figure 4 (a) and (b) are schematic cross-sectional views for illustrating the X-ray detection modules 110 and 110a in the comparative example. The moisture-proof portion 17 provided in the X-ray detection modules 110 and 110a does not include the housing portion 7a described later.

[0089] like Figure 4 As shown in (a), when the scintillator 5 is formed, a convex portion 5b1 may be locally generated at the upper end 5b of the scintillator 5. For example, when the scintillator 5 is formed by vacuum evaporation, a high crystal may be locally formed. Figure 4 The X-ray detection module 110 illustrated in (a) is provided with a reflective layer 6, but the same is true for a case where the reflective layer 6 is not provided (see Figure 5 ).

[0090] In addition, if Figure 4 As shown in (b), when the reflective layer 6 is formed, the thickness of the reflective layer 6 may be locally thickened to form a convex portion 6a. For example, there may be a case where a thicker portion is locally formed due to the mixing of impurities or foreign matter. Figure 4 The X-ray detection module 110a illustrated in (b) is provided with a scintillator 5 including a plurality of columnar crystals, but the same is true for a case where a quadrangular columnar scintillator 5 including terbium-activated gadolinium sulfate or the like is provided.

[0091] As described above, since the pressure inside the space defined by the moisture-proof portion 17 is lower than the atmospheric pressure, the moisture-proof portion 17 is pushed to the upper end 5b of the scintillator 5 or the upper end of the reflecting layer 6 under the action of the atmospheric pressure. Therefore, if there is a local convex portion at least at one of the upper end 5b of the scintillator 5 and the upper end of the reflecting layer 6, the local convex portion is pressed and local stress F is easily generated in the scintillator 5. If the local stress F is generated in the scintillator 5, for example, the crystallization of the scintillator 5 may be hindered.

[0092] In this case, if the formation conditions of the scintillator 5 are strictly specified or if impurities and foreign matter are further suppressed from mixing into the reflective layer 6, the formation of the local convex portion can be suppressed. However, even so, it is difficult to completely eliminate the formation of the local convex portion. In addition, it may also lead to an increase in the manufacturing cost of the X-ray detection module 1.

[0093] To this end, in the X-ray detection module 10 of this embodiment, as shown in FIG. Figure 2 As shown in the figure, a receiving portion 7a is provided in the moisture-proof portion 7. The receiving portion 7a is opened on the surface of the moisture-proof portion 7 on the side close to the scintillator 5. In addition, the receiving portion 7a protrudes to the surface of the moisture-proof portion 7 on the side opposite to the scintillator 5. Such a receiving portion 7a can be formed by, for example, partially pressing the surface of the moisture-proof portion 7 to partially plastically deform the moisture-proof portion 7.

[0094] Since the local convex portion 5b1 of the scintillator 5 and the local convex portion 6a of the reflective layer 6 are formed at random positions, it is difficult to pre-set the position of the receiving portion 7a. For this purpose, for example, the position of the convex portion 5b1 and the position of the convex portion 6a can be detected for each X-ray detection module 10, and the receiving portion 7a can be formed based on the obtained position information. In this case, the shape and size of the convex portion 5b1 and the shape and size of the convex portion 6a can be measured together, and the shape and size of the receiving portion 7a can be changed according to the information related to the shape and size.

[0095] As described above, the moisture-proof portion 17 is pushed toward the scintillator 5 by atmospheric pressure, so at least a portion of the interior of the housing portion 7a may contact the convex portion 5b1 or the convex portion 6a. However, if the convex portion 5b1 and the convex portion 6a are housed in the housing portion 7a, the local stress F can be relieved.

[0096] In addition, when the height H of the convex portion 5b1 and the convex portion 6a is low, the local stress F becomes small, and therefore, the receiving portion 7a can be omitted. In this case, when the height H is configured to be greater than the thickness T of the moisture-proof portion 7, it is preferred to provide the receiving portion 7a. When the height H is less than the thickness T of the moisture-proof portion 7, the receiving portion 7a can be omitted or provided.

[0097] Figure 5 This is a schematic cross-sectional view for illustrating an X-ray detection module 10a according to another embodiment.

[0098] As described above, there is a case where the reflective layer 6 is omitted. In the case where the reflective layer 6 is omitted, Figure 5 As shown, there is a case where a high crystal is locally formed when the scintillator 5 is formed. In this case, if the local protrusion 5b1 of the scintillator 5 is accommodated in the accommodation portion 7a, the local stress F can be relieved.

[0099] Figure 6 This is a schematic cross-sectional view for illustrating an X-ray detection module 10b according to still another embodiment.

[0100] When the scintillator 5 is formed, a crystal with a high height may be formed locally. However, when the reflective layer 6 is formed, for example, a local convex portion 6a may be generated in the reflective layer 6 due to the mixing of impurities and foreign matter. In this case, if the local convex portion 6a of the reflective layer 6 is accommodated in the accommodation portion 7a, the local stress F can also be relieved.

[0101] That is, the housing portion 7 a can house any one of the convex portion 5 b 1 of the scintillator 5 , the convex portion 6 a of the reflective layer 6 , and the convex portion 5 b 1 of the scintillator 5 and the portion of the reflective layer 6 covering the convex portion 5 b 1 of the scintillator 5 .

[0102] Several embodiments of the present invention are described above, but these embodiments are only examples and do not limit the scope of the invention. These new embodiments can also be implemented in various other ways, and various omissions, substitutions, changes, etc. can be made without departing from the technical concept of the invention. These embodiments and their variations are included in the scope or gist of the invention, and are included in the invention described in the claims and their equivalents. In addition, the above embodiments can be implemented in combination with each other.

Claims

1. A radiation detection module, characterized in that: include: An array substrate having a plurality of photoelectric conversion parts; A scintillator, the scintillator being disposed on the plurality of photoelectric conversion parts; as well as a moisture-proof portion, the moisture-proof portion covers the upper side of the scintillator and has a receiving portion for receiving a local convex portion of the upper end of the scintillator, The environment of the gap inside the scintillator and the environment between the receiving portion and the convex portion of the scintillator are decompressed to be lower than the atmospheric pressure.

2. The radiation detection module according to claim 1, wherein: The radiation detection module further includes a reflection layer, which is disposed between the upper end of the scintillator and the moisture-proof portion. The housing portion houses the convex portion of the scintillator and a portion of the reflective layer that covers the convex portion of the scintillator.

3. A radiation detection module, characterized in that: include: An array substrate having a plurality of photoelectric conversion parts; A scintillator, the scintillator being disposed on the plurality of photoelectric conversion parts; a reflective layer, the reflective layer being disposed on the scintillator; and a moisture-proof portion, the moisture-proof portion covers the upper portion of the reflective layer and has a receiving portion for receiving a local convex portion of the upper end of the reflective layer, The environment of the gap inside the scintillator and the environment between the receiving portion and the convex portion of the scintillator are decompressed to be lower than the atmospheric pressure.

4. The radiation detection module according to any one of claims 1 to 3, characterized in that: The moisture-proof portion is in a sheet shape, and has a thickness of 10 μm or more and 50 μm or less.

5. The radiation detection module according to any one of claims 1 to 3, characterized in that: The moisture-proof portion is a laminated sheet formed by laminating at least two of a resin film, a metal film, and an inorganic film other than the metal film, or a sheet containing metal. The metal film is a film including at least one of aluminum-containing metal, copper-containing metal, magnesium-containing metal, tungsten-containing metal, stainless steel, and Kovar material.

6. The radiation detection module according to claim 4, characterized in that: The moisture-proof portion is a laminated sheet formed by laminating at least two of a resin film, a metal film, and an inorganic film other than the metal film, or a sheet containing metal. The metal film is a film including one of aluminum-containing metal, copper-containing metal, magnesium-containing metal, tungsten-containing metal, stainless steel, and Kovar material.

7. A radiation detector, characterized in that: include: The radiation detection module according to any one of claims 1 to 6; as well as A circuit substrate is electrically connected to the radiation detection module.

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