WO2021033663A1

WO2021033663A1 - Method for manufacturing radiation detector

Info

Publication number: WO2021033663A1
Application number: PCT/JP2020/030992
Authority: WO
Inventors: 宗貴加藤
Original assignee: 富士フイルム株式会社
Priority date: 2019-08-16
Filing date: 2020-08-17
Publication date: 2021-02-25
Also published as: JPWO2021033663A1; TW202113395A

Abstract

This method for manufacturing a radiation detector comprises: a step for forming a sensor substrate, in which a flexible substrate is provided on a support body, and a plurality of pixels for storing a charge based on emitted radiation are provided in a pixel region of the substrate; a step for peeling off the sensor substrate provided with the plurality of pixels from the support body; a step for providing, on a second surface of the sensor substrate, a reinforcing member for reinforcing the substrate, the second surface being the surface peeled off from the support body; and a step for cutting off a portion of a layered body obtained by layering the reinforcing member and the substrate, said portion corresponding to an area outside of the pixel region of the substrate. This method for manufacturing a radiation detector makes it is possible to easily increase the proportion of the pixel region where the pixels are formed on the substrate.

Description

Radiation detector manufacturing method

The present invention relates to a method for manufacturing a radiation detector.

Conventionally, a radiographic imaging device that performs radiographic imaging for the purpose of medical diagnosis is known. In such a radiation image capturing apparatus, a radiation detector for detecting radiation transmitted through a subject and generating a radiation image is used.

The radiation detector includes a conversion layer such as a scintillator that converts radiation into light, and a substrate provided with a plurality of pixels that accumulate charges generated in response to the light converted by the conversion layer. is there. As such a radiation detector, a so-called narrow frame radiation detector in which the distance from the pixel region provided with pixels to the edge of the radiation detector is short is known. For example, in the technique described in Japanese Patent Application Laid-Open No. 2014-13193, a radiation detector having a narrow frame is manufactured by cutting a sensor substrate along a side of a pixel region.

By the way, as a radiation detector, a radiation detector using a flexible base material is known. By using a flexible base material, for example, the radiation imaging device (radiation detector) can be made lighter, and the subject may be easily photographed.

In such a radiation detector using a flexible base material, the sensor substrate is easily bent, so that unlike the technique described in Japanese Patent Application Laid-Open No. 2014-13193, it is difficult to cut the sensor substrate and the sensor. Pixels may be damaged by cutting the substrate.

The present disclosure provides a method for manufacturing a radiation detector that can easily increase the proportion of pixel regions in which pixels are formed on a substrate.

In the method for manufacturing a radiation detector according to the first aspect of the present disclosure, a flexible base material is provided on a support, and a plurality of pixels accumulating charges according to the irradiated radiation are provided in a pixel region of the base material. A step of forming the provided substrate, a step of peeling the substrate provided with a plurality of pixels from the support, and a step of providing a reinforcing member for reinforcing the strength of the base material on the surface of the substrate peeled from the support. A step of cutting a portion of the base material corresponding to the outside of the pixel region of the laminated body in which the reinforcing member and the base material are laminated.

Further, in the method for manufacturing the radiation detector according to the second aspect of the present disclosure, the cut surfaces of the reinforcing member and the base material are flush with each other in the method for manufacturing the radiation detector according to the first aspect.

Further, in the method for manufacturing a radiation detector according to the third aspect of the present disclosure, in the method for manufacturing a radiation detector according to the first aspect or the second aspect, the substrate is a cable on a surface provided with a plurality of pixels. Has a terminal region provided with a terminal portion for electrically connecting the two, and in the step of cutting the base material, the region other than the terminal region is cut.

Further, in the method for manufacturing the radiation detector according to the fourth aspect of the present disclosure, in the method for manufacturing the radiation detector according to the third aspect, the cable is electrically connected to the terminal portion before the step of peeling the substrate from the support. Further provided with a process of connecting the elements.

Further, in the method for manufacturing a radiation detector according to the fifth aspect of the present disclosure, in the method for manufacturing a radiation detector according to the first aspect or the second aspect, after the step of cutting the base material, the base material of the substrate is formed. A step of providing a terminal portion for electrically connecting a cable to a surface provided with a plurality of pixels along the side on the cut side is further provided.

Further, in the method for manufacturing a radiation detector according to the sixth aspect of the present disclosure, in the method for manufacturing a radiation detector according to any one of the first to fifth aspects, the reinforcing member is more rigid than the base material. Is high.

Further, the method for manufacturing the radiation detector according to the seventh aspect of the present disclosure is the method for manufacturing the radiation detector according to any one of the first to sixth aspects, wherein the reinforcing member has a flexural modulus of 500 MPa. It is 3000 MPa or less.

Further, in the method for manufacturing a radiation detector according to the eighth aspect of the present disclosure, in the method for manufacturing a radiation detector according to any one of the first to seventh aspects, the reinforcing member is made of polycarbonate and polyethylene terephthalate. It is a member made of at least one material.

Further, the method for manufacturing the radiation detector according to the ninth aspect of the present disclosure is the method for manufacturing the radiation detector according to any one of the first to seventh aspects, wherein the base material is provided with a plurality of pixels. In the step of cutting the laminated body having a mark on the marked surface, the position corresponding to the mark is cut.

Further, the method for manufacturing the radiation detector according to the tenth aspect of the present disclosure is the step of forming the substrate and the method for manufacturing the substrate in any one of the first to ninth aspects of the method for manufacturing the radiation detector. During the step of peeling from the support, a step of forming a conversion layer for converting radiation into light is further provided on the surface of the base material provided with the plurality of pixels, and each of the plurality of pixels is converted by the conversion layer. Accumulates the charge according to the light.

Further, in the method for manufacturing a radiation detector according to the tenth aspect of the present disclosure, in the method for manufacturing a radiation detector according to any one of the first to ninth aspects, each of the plurality of pixels emits radiation. It includes a sensor unit that receives and generates an electric charge, and accumulates the electric charge generated by the sensor unit.

According to the present disclosure, it is possible to easily increase the ratio of the pixel region in which the pixels are formed on the substrate.

It is a block diagram which shows an example of the main part structure of an electric system in the radiation image taking apparatus of 1st Embodiment. It is a top view from the 1st surface side of the base material as an example of the radiation detector of 1st Embodiment. FIG. 2 is a cross-sectional view taken along the line AA of the radiation detector shown in FIG. It is sectional drawing BB of the radiation detector shown in FIG. It is a figure for demonstrating an example of the manufacturing method of the radiation detector of 1st Embodiment. It is a figure for demonstrating an example of the manufacturing method of the radiation detector of 1st Embodiment. It is a figure for demonstrating an example of the manufacturing method of the radiation detector of 1st Embodiment. It is a figure for demonstrating an example of the manufacturing method of the radiation detector of 1st Embodiment. It is a figure for demonstrating an example of the manufacturing method of the radiation detector of 1st Embodiment. It is a figure for demonstrating an example of the manufacturing method of the radiation detector of 1st Embodiment. It is a figure for demonstrating an example of the manufacturing method of the radiation detector of 1st Embodiment. It is a figure for demonstrating an example of the manufacturing method of the radiation detector of 1st Embodiment. FIG. 5 is a plan view of an example of the radiation detector of the second embodiment as viewed from the first surface side of the base material. FIG. 5 is a cross-sectional view taken along the line AA of the radiation detector shown in FIG. FIG. 5 is a sectional view taken along line BB of the radiation detector shown in FIG. It is a figure for demonstrating an example of the manufacturing method of the radiation detector of 2nd Embodiment. It is a figure for demonstrating an example of the manufacturing method of the radiation detector of 2nd Embodiment. It is a figure for demonstrating an example of the manufacturing method of the radiation detector of 2nd Embodiment. It is a figure for demonstrating an example of the manufacturing method of the radiation detector of 2nd Embodiment. It is a figure for demonstrating an example of the manufacturing method of the radiation detector of 2nd Embodiment. It is a figure for demonstrating an example of the manufacturing method of the radiation detector of 2nd Embodiment. It is a figure for demonstrating an example of the manufacturing method of the radiation detector of 2nd Embodiment. FIG. 5 is a cross-sectional view taken along the line AA of another example radiation detector. It is sectional drawing of an example of the radiation imaging apparatus of embodiment which is housed in a housing. It is sectional drawing of another example of the radiation imaging apparatus of embodiment which is housed in a housing. It is sectional drawing of another example of the radiation imaging apparatus of embodiment which is housed in a housing.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present embodiment does not limit the present invention.

[First Embodiment]
The radiation detector of the present embodiment has a function of detecting radiation transmitted through a subject and outputting image information representing a radiation image of the subject. The radiation detector of the present embodiment includes a sensor substrate and a conversion layer that converts radiation into light (see FIG. 2, sensor substrate 12 and conversion layer 14 of the radiation detector 10). The sensor substrate 12 of this embodiment is an example of the substrate of the present disclosure.

First, an outline of an example of the configuration of the electrical system in the radiation imaging apparatus of this embodiment will be described with reference to FIG. FIG. 1 is a block diagram showing an example of a configuration of a main part of an electrical system in the radiation imaging apparatus of the present embodiment.

As shown in FIG. 1, the radiation imaging device 1 of the present embodiment includes a radiation detector 10, a control unit 100, a drive unit 102, a signal processing unit 104, an image memory 106, and a power supply unit 108.

The radiation detector 10 includes a sensor substrate 12 and a conversion layer (see FIG. 2) that converts radiation into light. The sensor substrate 12 includes a flexible base material 11 and a plurality of pixels 30 provided on the first surface 11A of the base material 11. In the following, the plurality of pixels 30 may be simply referred to as “pixel 30”.

As shown in FIG. 1, each pixel 30 of the present embodiment has a sensor unit 34 that generates and accumulates electric charges according to the light converted by the conversion layer, and a switching element 32 that reads out the electric charges accumulated by the sensor unit 34. To be equipped with. In this embodiment, as an example, a thin film transistor (TFT: Thin Film Transistor) is used as the switching element 32. Therefore, in the following, the switching element 32 will be referred to as "TFT32". In the present embodiment, the sensor unit 34 and the TFT 32 are formed, and a layer in which the pixels 30 are formed on the first surface 11A of the base material 11 is provided as a flattened layer.

The pixel 30 corresponds to the pixel region 35 of the sensor substrate 12 in one direction (scanning wiring direction corresponding to the horizontal direction in FIG. 1, hereinafter also referred to as “row direction”) and an intersecting direction with respect to the row direction (corresponding to the vertical direction in FIG. It is arranged in a two-dimensional manner along the signal wiring direction (hereinafter also referred to as "row direction"). In FIG. 1, the arrangement of the pixels 30 is shown in a simplified manner. For example, 1024 pixels × 1024 pixels 30 are arranged in the row direction and the column direction.

Further, the radiation detector 10 is provided with a plurality of scanning wires 38 for controlling the switching state (on and off) of the TFT 32, which are provided for each row of the pixel 30, and for each column of the pixel 30. A plurality of signal wirings 36 from which the electric charge accumulated in the sensor unit 34 is read out are provided so as to intersect each other. Each of the plurality of scanning wires 38 is connected to the drive unit 102 via the cable 112A (see FIG. 2) to drive the TFT 32 output from the drive unit 102 to control the switching state. A signal flows through each of the plurality of scanning wires 38. Further, each of the plurality of signal wirings 36 is connected to the signal processing unit 104 via the cable 112B (see FIG. 2), so that the electric charge read from each pixel 30 is signal-processed as an electric signal. It is output to unit 104. The signal processing unit 104 generates and outputs image data corresponding to the input electric signal.

A control unit 100, which will be described later, is connected to the signal processing unit 104, and the image data output from the signal processing unit 104 is sequentially output to the control unit 100. An image memory 106 is connected to the control unit 100, and image data sequentially output from the signal processing unit 104 is sequentially stored in the image memory 106 under the control of the control unit 100. The image memory 106 has a storage capacity capable of storing a predetermined number of image data, and each time a radiographic image is taken, the image data obtained by the taking is sequentially stored in the image memory 106.

The control unit 100 includes a CPU (Central Processing Unit) 100A, a memory 100B including a ROM (Read Only Memory) and a RAM (Random Access Memory), and a non-volatile storage unit 100C such as a flash memory. An example of the control unit 100 is a microcomputer or the like. The control unit 100 controls the overall operation of the radiographic imaging apparatus 1.

In the radiation imaging device 1 of the present embodiment, the image memory 106, the control unit 100, and the like are formed on the control board 110.

Further, in the sensor unit 34 of each pixel 30, a common wiring 39 is provided in the wiring direction of the signal wiring 36 in order to apply a bias voltage to each pixel 30. By connecting the common wiring 39 to an external bias power supply (not shown) of the sensor board 12, a bias voltage is applied to each pixel 30 from the bias power supply.

The power supply unit 108 supplies electric power to various elements and circuits such as the control unit 100, the drive unit 102, the signal processing unit 104, the image memory 106, and the power supply unit 108. In FIG. 1, in order to avoid complications, the wiring connecting the power supply unit 108 with various elements and various circuits is omitted.

Further, the radiation imaging apparatus 1 will be described in detail. FIG. 2 is an example of a plan view of the radiation detector 10 of the present embodiment as viewed from the first surface 11A side of the base material 11. Further, FIG. 3A is an example of a cross-sectional view taken along the line AA of the radiation detector 10 in FIG. 2, and FIG. 3B is an example of a cross-sectional view taken along the line BB of the radiation detector 10 in FIG.

The first surface 11A of the base material 11 is divided into a terminal region 60A in which the terminal portion 60 is provided and a terminal region outside 60B in which the terminal portion 60 is not provided. The pixel region 35 provided with the above-mentioned pixel 30 is provided in the terminal region outer 60B.

The base material 11 is a resin sheet that is flexible and contains, for example, a plastic such as PI (PolyImide: polyimide). The thickness of the base material 11 is such that the desired flexibility can be obtained according to the hardness of the material, the size of the sensor substrate 12 (the area of the first surface 11A or the second surface 11B), and the like. Good. As an example of flexibility, in the case of a rectangular base material 11 alone, with one side of the base material 11 fixed, the gravity of the base material 11 is 2 mm at a position 10 cm away from the fixed side. As described above, the base material 11 hangs down (becomes lower than the height of the fixed side). As a specific example when the base material 11 is a resin sheet, a thickness of 5 μm to 125 μm may be used, and a thickness of 20 μm to 50 μm is more preferable.

The base material 11 has a property that can withstand the production of the pixel 30, and in the present embodiment, it has a property that can withstand the production of an amorphous silicon TFT (a-Si TFT). As such a characteristic of the base material 11, the coefficient of thermal expansion (CTE: Coefficient of Thermal Expansion) at 300 ° C. to 400 ° C. is about the same as that of an amorphous silicon (Si) wafer (for example, ± 5 ppm / K). Specifically, it is preferably 20 ppm / K or less. Further, as the heat shrinkage rate of the base material 11, it is preferable that the heat shrinkage rate at 400 ° C. is 0.5% or less when the thickness is 25 μm. Further, the elastic modulus of the base material 11 preferably does not have a transition point possessed by a general PI in the temperature range between 300 ° C. and 400 ° C., and the elastic modulus at 500 ° C. is 1 GPa or more.

Further, the base material 11 of the present embodiment has a fine particle layer containing inorganic fine particles having an average particle diameter of 0.05 μm or more and 2.5 μm or less and absorbing backscattered rays in order to suppress backscattered rays by itself. It is preferable to have. As such inorganic fine particles, in the case of the resinous base material 11, it is preferable to use an inorganic material having an atomic number larger than the atoms constituting the organic material which is the

base material

11 and 30 or less. Specific examples of such fine particles include SiO2, which is an oxide of Si having an atomic number of 14, MgO, which is an oxide of Mg having an atomic number of 12, Al2O3, which is an oxide of Al having an atomic number of 13. Examples thereof include TiO2, which is an oxide of Ti having an atomic number of 22. Specific examples of the resin sheet having such characteristics include XENOMAX (registered trademark).

The above thickness in this embodiment was measured using a micrometer. The coefficient of thermal expansion was measured according to JIS K7197: 1991. In the measurement, test pieces were cut out from the main surface of the base material 11 at different angles of 15 degrees, the coefficient of thermal expansion was measured for each of the cut out test pieces, and the highest value was taken as the coefficient of thermal expansion of the base material 11. .. The coefficient of thermal expansion is measured at intervals of 10 ° C. from -50 ° C to 450 ° C in each of the MD (Machine Direction) direction and the TD (Transverse Direction) direction, and (ppm / ° C) is converted to (ppm / K). did. To measure the coefficient of thermal expansion, a TMA4000S device manufactured by MAC Science Co., Ltd. was used, the sample length was 10 mm, the sample width was 2 mm, the initial load was 34.5 g / mm2, the heating rate was 5 ° C / min, and the atmosphere was argon. And said.

The base material 11 having the desired flexibility is not limited to a resin sheet or the like. For example, the base material 11 may be a glass substrate or the like having a relatively thin thickness.

As shown in FIGS. 2 to 3B, the plurality of pixels 30 are provided in a part of the inside of 60B outside the terminal region on the first surface 11A of the base material 11. Further, in the sensor substrate 12 of the present embodiment, the pixel 30 is not provided in the terminal region 60A on the first surface 11A of the substrate 11. In the present embodiment, the region where the pixel 30 is provided on the first surface 11A of the base material 11 is defined as the pixel region 35.

Further, as shown in FIGS. 2 to 3B, the conversion layer 14 of the present embodiment covers the pixel region 35. In this embodiment, a scintillator containing CsI (cesium iodide) is used as an example of the conversion layer 14. Examples of such scintillators include CsI: Tl (cesium iodide added with thallium) and CsI: Na (cesium iodide added with sodium) having an emission spectrum of 400 nm to 700 nm during X-ray irradiation. It is preferable to include it. The emission peak wavelength of CsI: Tl in the visible light region is 565 nm.

As shown in FIGS. 3A and 3B, an adhesive layer 40, a reflective layer 42, an adhesive layer 44, and a protective layer 46 are provided on the conversion layer 14 of the present embodiment.

The adhesive layer 40 covers the entire surface of the conversion layer 14. The adhesive layer 40 has a function of fixing the reflective layer 42 on the conversion layer 14. The adhesive layer 40 preferably has light transmission. As the material of the adhesive layer 40, for example, an acrylic adhesive, a hot melt adhesive, and a silicone adhesive can be used. Examples of the acrylic pressure-sensitive adhesive include urethane acrylate, acrylic resin acrylate, and epoxy acrylate. Examples of the hot melt adhesive include EVA (ethylene / vinyl acetate copolymer resin), EAA (ethylene / acrylic acid copolymer resin), EEA (ethylene-ethylacrylate copolymer resin), and EMMA (ethylene-methacryl). Thermoplastics such as methyl acid copolymer) can be mentioned. The thickness of the adhesive layer 40 is preferably 2 μm or more and 7 μm or less. By setting the thickness of the adhesive layer 40 to 2 μm or more, the effect of fixing the reflective layer 42 on the conversion layer 14 can be sufficiently exhibited. Further, the risk of forming an air layer between the conversion layer 14 and the reflection layer 42 can be suppressed. When an air layer is formed between the conversion layer 14 and the reflection layer 42, the light emitted from the conversion layer 14 is emitted between the air layer and the conversion layer 14 and between the air layer and the reflection layer 42. Multiple reflections that repeat reflections may occur. Further, by setting the thickness of the adhesive layer 40 to 7 μm or less, it is possible to suppress a decrease in MTF (Modulation Transfer Function) and DQE (Detective Quantum Efficiency).

The reflective layer 42 covers the entire surface of the adhesive layer 40. The reflective layer 42 has a function of reflecting the light converted by the conversion layer 14. The reflective layer 42 is preferably made of an organic material. As the material of the reflective layer 42, for example, white PET (Polyethylene terephthalate), TiO ₂ , Al ₂ O ₃ , foamed white PET, polyester-based highly reflective sheet, specular reflective aluminum and the like can be used. White PET is obtained _{by adding a white pigment such as TiO 2} or barium sulfate to PET, and foamed white PET is white PET having a porous surface. The polyester-based high-reflection sheet is a sheet (film) having a multilayer structure in which a plurality of thin polyester sheets are stacked. The thickness of the reflective layer 42 is preferably 10 μm or more and 40 μm or less.

The adhesive layer 44 covers the entire surface of the reflective layer 42. The end of the adhesive layer 44 extends to the surface of the sensor substrate 12. That is, the adhesive layer 44 is adhered to the sensor substrate 12 at its end. The adhesive layer 44 has a function of fixing the reflective layer 42 and the protective layer 46 to the conversion layer 14. As the material of the adhesive layer 44, the same material as the material of the adhesive layer 40 can be used, but the adhesive force of the adhesive layer 44 is preferably larger than that of the adhesive layer 40.

The protective layer 46 is provided so as to cover the entire conversion layer 14 and its end portion to cover a part of the sensor substrate 12. The protective layer 46 functions as a moisture-proof film that prevents moisture from entering the conversion layer 14. As the material of the protective layer 46, for example, PET, PPS (PolyPhenylene Sulfide: polyphenylene sulfide), OPP (Oriented PolyPropylene: biaxially stretched polypropylene film), PEN (PolyEthylene Naphthalate: polyethylene naphthalate), PI and other organic materials are included. Membranes and parylene (registered trademark) can be used. Further, as the protective layer 46, a laminated film of a resin film and a metal film may be used. Examples of the laminated film of the resin film and the metal film include a sheet of Alpet (registered trademark).

Further, as shown in FIGS. 3A and 3B, in the sensor substrate 12 of the radiation detector 10 of the present embodiment, the antistatic layer 54 and the adhesive 52 are interposed on the second surface 11B side of the substrate 11. , The reinforcing member 50 is provided.

The reinforcing member 50 has a function of reinforcing the strength of the base material 11. The reinforcing member 50 of the present embodiment has higher flexural rigidity than the base material 11, and the dimensional change (deformation) with respect to the force applied in the direction perpendicular to the surface facing the conversion layer 14 is the second of the base material 11. It is smaller than the dimensional change with respect to the force applied in the direction perpendicular to the surface 11B of. Specifically, the bending rigidity of the reinforcing member 50 is preferably 100 times or more the bending rigidity of the base material 11. Further, the thickness of the reinforcing member 50 of the present embodiment is thicker than the thickness of the base material 11. For example, when XENOMAX (registered trademark) is used as the base material 11, the thickness of the reinforcing member 50 is preferably about 0.2 mm to 0.25 mm.

Specifically, it is preferable to use a material having a flexural modulus of 500 MPa or more and 3000 MPa or less for the reinforcing member 50 of the present embodiment. The reinforcing member 50 preferably has a higher bending rigidity than the base material 11 from the viewpoint of suppressing the bending of the base material 11. When the flexural modulus is lowered, the flexural rigidity is also lowered, and in order to obtain the desired flexural rigidity, the thickness of the reinforcing member 50 must be increased, and the thickness of the entire radiation detector 10 is increased. .. Considering the material of the reinforcing member 50 described above, the thickness of the reinforcing member 50 tends to be relatively thick when trying to obtain a bending rigidity exceeding ^{140000 Pacm 4.} Therefore, considering that appropriate rigidity can be obtained and the thickness of the entire radiation detector 10 is taken into consideration, the material used for the reinforcing member 50 is more preferably having a flexural modulus of 500 MPa or more and 3000 MPa or less. Further, the bending rigidity of the reinforcing member 50 ^{is preferably 540 Pacm 4} or more and 140000 Pacm ⁴ or less.

Further, the coefficient of thermal expansion of the reinforcing member 50 of the present embodiment is preferably close to the coefficient of thermal expansion of the material of the conversion layer 14, and more preferably the coefficient of thermal expansion of the reinforcing member 50 with respect to the coefficient of thermal expansion of the conversion layer 14. The ratio (coefficient of thermal expansion of the reinforcing member 50 / coefficient of thermal expansion of the conversion layer 14) is preferably 0.5 or more and 2 or less. The coefficient of thermal expansion of such a reinforcing member 50 is preferably 30 ppm / K or more and 80 ppm / K or less. For example, when the conversion layer 14 is made of CsI: Tl, the coefficient of thermal expansion is 50 ppm / K. In this case, as a material relatively close to the conversion layer 14, PVC (Polyvinyl Chloride) having a coefficient of thermal expansion of 60 ppm / K to 80 ppm / K and a coefficient of thermal expansion of 70 ppm / K to 80 ppm / K are used. Acrylic, PET with a coefficient of thermal expansion of 65 ppm / K to 70 ppm / K, PC (Polycarbonate) with a coefficient of thermal expansion of 65 ppm / K, and Teflon with a coefficient of thermal expansion of 45 ppm / K to 70 ppm / K (registered). Trademark) and the like. Further, in consideration of the flexural modulus described above, the material of the reinforcing member 50 is more preferably a material containing at least one of PET and PC.

From the viewpoint of elasticity, the reinforcing member 50 preferably contains a material having a yield point. In the present embodiment, the “yield point” refers to a phenomenon in which the stress drops suddenly when the material is pulled, and the strain does not increase on the curve showing the relationship between the stress and the strain. The point of increase, which refers to the top of the stress-strain curve when a tensile strength test is performed on a material. Resins having a yield point generally include resins that are hard and sticky, and resins that are soft and sticky and have moderate strength. Examples of the hard and sticky resin include PC and the like. Further, examples of the resin having a softness, a strong stickiness, and a medium strength include polypropylene and the like.

The reinforcing member 50 of this embodiment is a substrate made of plastic. The plastic used as the material of the reinforcing member 50 is preferably a thermoplastic resin for the reasons described above, and is preferably PC, PET, styrene, acrylic, polyacetase, nylon, polypropylene, ABS (Acrylonitrile Butadinee Styrene), engineering plastic, and polyphenylene ether. At least one of. The reinforcing member 50 is preferably at least one of polypropylene, ABS, engineering plastic, PET, and polyphenylene ether, and more preferably at least one of styrene, acrylic, polyacetase, and nylon. , PC and PET are more preferable.

On the other hand, a plurality of terminal portions 60 (16 in total in this embodiment) are provided in the terminal region 60A of the radiation detector 10 of the present embodiment. As shown in FIG. 2, the terminal region 60A is provided on each of a pair of sides and sides facing the pair of sides (total of three sides) of the rectangular sensor substrate 12 (base material 11). The terminal region 60A refers to a region on the first surface 11A of the base material 11 where a plurality of terminal portions 60 are provided, and includes at least a region where the terminal portions 60 are in contact with the first surface 11A. As an example, in the present embodiment, the terminal region includes at least the region where the terminal portion 60 is in contact with the first surface 11A over the entire side of the sensor substrate 12 (base material 11) where the terminal portion 60 is provided. It is called 60A.

As shown in FIG. 2, a cable 112 is electrically connected to each of the terminal portions 60 provided in the terminal region 60A of the base material 11. Specifically, as shown in FIG. 2, the cable 112A is thermocompression-bonded to each of a plurality of terminal portions 60 (8 each in FIG. 2) provided on each of the pair of opposite sides of the base material 11. ing. The cable 112A is a so-called COF (Chip on Film), and the cable 112A is equipped with a drive IC (Integrated Circuit) 210. The drive IC 210 is connected to a plurality of signal lines (not shown) included in the cable 112A. The method of electrically connecting the terminal portion 60 and the cable 112A is not limited to this embodiment, and may be, for example, electrically connected by a connector. Examples of such a connector include a ZIF (Zero Insert Force) structure connector and a Non-ZIF structure connector. In the present embodiment, when the cable 112A and the cable 112B described later are generically referred to without distinction, they are simply referred to as "cable 112".

The other end of the cable 112A, which is electrically connected to the terminal portion 60 of the sensor board 12, and the other end on the opposite side, is electrically connected to the connection area 202 of the drive board 200. As an example, in the present embodiment, a plurality of signal lines (not shown) included in the cable 112A are thermocompression-bonded to the drive board 200 to form circuits and elements mounted on the drive board 200 (not shown). Be connected. The method of electrically connecting the drive board 200 and the cable 112A is not limited to this embodiment, and may be, for example, electrically connected by a connector. Examples of such a connector include a ZIF structure connector and a Non-ZIF structure connector.

The drive board 200 of this embodiment is a flexible PCB (Printed Circuit Board) board, which is a so-called flexible board. Further, the circuit components (not shown) mounted on the drive board 200 are components mainly used for processing digital signals (hereinafter, referred to as "digital components"). Digital components tend to have a relatively smaller area (size) than analog components, which will be described later. Specific examples of digital components include digital buffers, bypass capacitors, pull-up / pull-down resistors, damping resistors, EMC (Electro Magnetic Compatibility) countermeasure chip components, power supply ICs, and the like. The drive substrate 200 does not necessarily have to be a flexible substrate, may be a non-flexible rigid substrate, or may use a rigid flexible substrate.

In the present embodiment, the drive unit 102 is realized by the drive board 200 and the drive IC 210 mounted on the cable 112A. The drive IC 210 includes various circuits and elements that realize the drive unit 102, which are different from the digital components mounted on the drive board 200.

On the other hand, the cable 112B is electrically connected to each of the plurality of (8 in FIG. 2) terminal portions 60 provided on the side where the cable 112A intersects one side of the electrically connected base material 11. There is. Like the cable 112A, the cable 112B is a so-called COF (Chip on Film), and the cable 112B is equipped with a signal processing IC 310. The signal processing IC 310 is connected to a plurality of signal lines (not shown) included in the cable 112B. The method of electrically connecting the terminal portion 60 and the cable 112B is not limited to this embodiment, and may be, for example, electrically connected by a connector. Examples of such a connector include a ZIF structure connector and a Non-ZIF structure connector.

The other end of the cable 112B, which is electrically connected to the terminal portion 60 of the sensor board 12, and the other end on the opposite side, is electrically connected to the connection area 302 of the signal processing board 300. As an example, in the present embodiment, a plurality of signal lines (not shown) included in the cable 112B are thermocompression-bonded to the signal processing board 300, so that circuits and elements mounted on the signal processing board 300 (not shown) and the like (not shown). ) Is connected. The method of electrically connecting the signal processing board 300 and the cable 112B is not limited to this embodiment, and may be, for example, electrically connected by a connector. Examples of such a connector include a ZIF structure connector and a Non-ZIF structure connector. Further, the method of electrically connecting the cable 112A and the drive board 200 and the method of electrically connecting the cable 112B and the signal processing board 300 may be the same or different. For example, the cable 112A and the drive board 200 may be electrically connected by thermocompression bonding, and the cable 112B and the signal processing board 300 may be electrically connected by a connector.

The signal processing board 300 of the present embodiment is a flexible PCB board like the drive board 200 described above, and is a so-called flexible board. The circuit components (not shown) mounted on the signal processing board 300 are components mainly used for processing analog signals (hereinafter, referred to as “analog components”). Specific examples of analog components include a charge amplifier, an analog-to-digital converter (ADC), a digital-to-analog converter (DAC), a power supply IC, and the like. Further, the circuit component of the present embodiment also includes a coil around a power supply having a relatively large component size and a large-capacity capacitor for smoothing. The signal processing substrate 300 does not necessarily have to be a flexible substrate, may be a non-flexible rigid substrate, or may use a rigid flexible substrate.

In the present embodiment, the signal processing unit 104 is realized by the signal processing board 300 and the signal processing IC 310 mounted on the cable 112B. The signal processing IC 310 includes various circuits and elements that realize the signal processing unit 104, which are different from the analog components mounted on the signal processing board 300.

Although a plurality of drive boards 200 and signal processing boards 300 are provided in each of the present embodiments, the number of drive boards 200 and signal processing boards 300 is not limited to this embodiment. For example, either one of the drive board 200 and the signal processing board 300 provided on each side of the sensor board 12 may be used as one board.

On the other hand, as shown in FIG. 3A, in the radiation detector 10 of the present embodiment, the cable 112 is electrically connected to the terminal portion 60 by thermocompression bonding the cable 112 to the terminal portion 60 via the connection layer 62. To.

The connection layer 62 has a function of electrically connecting the terminal portion 60 and the cable 112. Examples of the connecting layer 62 include an anisotropic conductive film, and ACF (Anisotropic Conductive Film) in which conductive particles (not shown) are dispersed in an adhesive that is cured by heat can be used.

As shown in FIG. 3A, the first surface 11A side of the base material 11 in the laminated body 63 in which the terminal portion 60, the connecting layer 62, and the cable 112 are laminated is covered with the reinforcing member 64. Further, the side surface of the laminate in which the terminal portion 60, the connection layer 62, and the cable 112 are laminated and the side surface of the base material 11 are covered with the reinforcing member 65. The reinforcing member 64 and the reinforcing member 65 have a function of strengthening the electrical connection between the terminal portion 60 and the cable 112. Further, the reinforcing member 64 and the reinforcing member 65 of the present embodiment have moisture resistance. As the reinforcing member 64 and the reinforcing member 65, for example, a moisture-proof insulating film can be used, and Tuffy (registered trademark) or the like, which is a moisture-proof insulating material for FPD (Flat Panel Display), can be used. Each of the reinforcing member 64 and the reinforcing member 65 may be a member made of the same material or a member made of a different material.

An example of the manufacturing method of the radiation detector 10 of the present embodiment will be described with reference to FIGS. 4A to 4H.

As shown in FIG. 4A, in the step of forming the sensor substrate 12, first, the substrate 11 is attached to a support 400 such as a glass substrate which is thicker than the substrate 11 via a release layer (not shown). To form. For example, when the base material 11 is formed by the laminating method, a sheet to be the base material 11 is attached onto the support 400. The second surface 11B of the base material 11 faces the support 400 side. The method of forming the base material 11 is not limited to this embodiment, and may be, for example, a form in which the base material 11 is formed by a coating method.

As shown in FIG. 4A, on the first surface 11A of the base material 11 of the present embodiment, an alignment mark 92 that serves as a mark of the cutting position in the step of cutting the laminate 19 shown in FIGS. 4F and 4G described later is formed. Provided. The timing of providing the alignment mark 92 is not limited to this embodiment. For example, after the step of electrically connecting the cable 112 to the terminal portion 60 shown in FIG. 4C described later, the first surface 11A of the base material 11 The alignment mark 92 may be provided on the. The alignment mark 92 of the present embodiment is an example of the mark of the present disclosure.

Further, the pixel 30 is formed in the pixel region 35 of 60B outside the terminal region of the first surface 11A of the base material 11. In the present embodiment, as an example, the pixel 30 is formed on the first surface 11A of the base material 11 via an undercoat layer (not shown) using SiN or the like. As a result, the sensor substrate 12 in which the pixels 30 are formed in the pixel region 35 is formed.

Further, as shown in FIG. 4B, in the step of forming the conversion layer 14, the conversion layer 14 is formed on the pixel 30 (pixel region 35). In the present embodiment, the CsI conversion layer 14 is formed as columnar crystals directly on the sensor substrate 12 by a vapor deposition method such as a vacuum deposition method, a sputtering method, and a CVD (Chemical Vapor Deposition) method. In this case, the side of the conversion layer 14 in contact with the pixel 30 is the growth direction base point side of the columnar crystal.

When a CsI scintillator is used as the conversion layer 14, the conversion layer 14 can be formed on the sensor substrate 12 by a method different from that of the present embodiment. For example, prepare an aluminum plate or the like on which CsI is vapor-deposited by a vapor phase deposition method, and attach the side of the CsI that is not in contact with the aluminum plate and the pixel 30 of the sensor substrate 12 with an adhesive sheet or the like. As a result, the conversion layer 14 may be formed on the sensor substrate 12. In this case, it is preferable that the entire conversion layer 14 including the aluminum plate is covered with the protective layer 46 and bonded to the pixels 30 of the sensor substrate 12. In this case, the side of the conversion layer 14 in contact with the pixel 30 is the tip side in the growth direction of the columnar crystal.

Further, unlike the radiation detector 10 of the present embodiment, GOS (Gd ₂ O ₂ S: Tb) or the like may be used as the conversion layer 14 instead of CsI. In this case, for example, a sheet in which GOS is dispersed in a binder such as resin is prepared by bonding a support formed of white PET or the like with an adhesive layer or the like, and the GOS support is not bonded. The conversion layer 14 can be formed on the sensor substrate 12 by sticking the side and the pixels 30 of the sensor substrate 12 with an adhesive sheet or the like. In addition, when CsI is used for the conversion layer 14, the conversion efficiency from radiation to visible light is higher than when GOS is used.

Further, a reflective layer 42 is provided via the adhesive layer 40 on the conversion layer 14 formed on the sensor substrate 12, and a protective layer 46 is provided via the adhesive layer 44.

Next, as shown in FIG. 4C, in the step of electrically connecting the cable 112 to the terminal portion 60, first, the terminal portion 60 is formed in the terminal region 60A on the first surface 11A of the base material 11. The timing of forming the terminal portion 60 in the terminal region 60A on the base material 11 is not limited to this embodiment. The terminal portion 60 may also be formed during either the step of forming the sensor substrate 12 (FIG. 4A) or the step of forming the conversion layer 14 (FIG. 4B), or the sensor substrate 12 may be formed. The terminal portion 60 may be formed at a timing between the step of forming the conversion layer 14 (FIG. 4A) and the step of forming the conversion layer 14 (FIG. 4B).

Further, the cable 112 is thermocompression bonded to the terminal portion 60 via the connection layer 62 to electrically connect the terminal portion 60 and the connection layer 62. Further, the reinforcing member 64 (see FIG. 3A) covers the laminated body 63. As an example, in the present embodiment, each of the cable 112A to which the drive board 200 is electrically connected and the cable 112B to which the signal processing board 300 is electrically connected are electrically connected to the terminal portion 60 of the base material 11. Although the form of connection has been described, the state of the cable 112 electrically connected to the terminal portion 60 of the base material 11 is not limited to this form. In other words, the timing of electrically connecting the drive board 200 to the cable 112A and the timing of electrically connecting the cable 112B to the signal processing board 300 are not limited to this embodiment. For example, after the step of cutting the laminate 19 shown in FIGS. 4F and 4G, which will be described later, the drive board 200 may be electrically connected to the cable 112A, and the cable 112B may be electrically connected to the signal processing board 300. Good. Further, the timing of electrically connecting the drive board 200 to the cable 112A and the timing of electrically connecting the cable 112B to the signal processing board 300 may be different.

Next, as shown in FIG. 4D, in the step of peeling the sensor substrate 12 from the support 400, a conversion layer 14 is provided to support the sensor substrate 12 in a state where the cable 112 is electrically connected to the terminal portion 60. Peel off from body 400. For example, in the laminating method, any of the four sides of the sensor substrate 12 (base material 11) is set as the starting point of peeling, and the sensor substrate 12 is gradually peeled off from the support 400 from the starting point toward the opposite side. , Perform mechanical peeling.

Next, as shown in FIG. 4E, in the step of providing the reinforcing member 50, the reinforcing member 50 is attached to the second surface 11B of the base material 11 via the antistatic layer 54 and the adhesive 52 (see FIGS. 3A and 3B). The reinforcing member 50 is formed by attaching or the like. As an example, in the present embodiment, the sensor substrate 12 in which the cable 112 is electrically connected to the terminal portion 60 is placed in a state where the second surface 11B of the substrate 11 is on the upper side, and the bonding device has an alignment function. set. The bonding device identifies the corners of the reinforcing member 50 provided with the adhesive 52 and the antistatic layer 54 and the corners of the second surface 11B of the base material 11 by an alignment function using an image pickup device or the like. The reinforcing member 50 and the sensor substrate 12 (base material 11) are aligned so that both corners overlap. As shown in FIG. 4E, the laminating device moves the roller 410 in the direction of the arrow P in a state where the reinforcing member 50 and the sensor substrate 12 (base material 11) are aligned to move the reinforcing member 50. It is attached to the second surface 11B of the base material 11.

Next, as shown in FIGS. 4F and 4G, in the step of cutting the laminated body 19 in which the sensor substrate 12 and the reinforcing member 50 are laminated, the terminals corresponding to the outside of the pixel region 35 in the base material 11 of the laminated body 19 The portion of 60B outside the region is cut. In the present embodiment, the portion of the laminated body 19 outside the pixel region 35 on the side opposite to the side to which the cable 112B of the base material 11 is electrically connected is cut. Specifically, as shown in FIGS. 4F and 4G, the position represented by the cutting line 90 is cut, the end portion of the laminated body 19 is cut off, and the radiation detector 10 is brought into the state shown in FIG. 4H. In this embodiment, the cutting line 90 is shown to indicate the cutting position, and is not actually provided on the first surface 11A of the base material 11.

As an example, in the present embodiment, the laminated body 19 in which the sensor substrate 12 and the reinforcing member 50 are laminated is set in a cutting device having an alignment function with the first surface 11A of the base material 11 facing up. .. The cutting device detects two alignment marks 92 provided on the first surface 11A of the base material 11 by an alignment function using an imaging device or the like, and determines the cutting line 90 based on the detected alignment marks 92. To do. Then, the cutting device cuts the laminated body 19 along the cutting line 90.

As described above, in the present embodiment, the laminated body 19 in which the base material 11 and the reinforcing member 50 are laminated is cut. In other words, since the base material 11 and the reinforcing member 50 are cut together, the cut surface 11C of the base material 11 and the cut surface 50C of the reinforcing member 50 are in a flush state as shown in FIG. 3B. The state in which the cut surface 11C of the base material 11 and the cut surface 50C of the reinforcing member 50 are "parallel" is not limited to the case where the cut surface 11C and the cut surface 50C are completely on the same plane. It refers to a state in which the reinforcing member 50 can be regarded as "facial" by allowing shrinkage, manufacturing error, and the like. In the present embodiment, the state in which the cut surface 11C of the base material 11 and the cut surface 50C of the reinforcing member 50 are "parallel" means that the cut surface 11C of the base material 11 and the cut surface 11C of the reinforcing member 50 are positioned. It is preferable that the difference is smaller than the difference in position between the side surface 11D of the base material 11 and the side surface 50D of the reinforcing member 50 that occurs when the reinforcing member 50 is attached to the base material 11 as shown in FIG. 3A. Refers to a state of ± 10 μm.

As described above, in the present embodiment, the radiation detectors 10 shown in FIGS. 2 to 3B and 4H are manufactured by the steps shown in FIGS. 4A to 4G.

As described above, in the method of manufacturing the radiation detector 10 of the present embodiment, the pixel region 60B outside the pixel region 35 of the laminate 19 in which the base material 11 and the laminate 19 are laminated is cut. The laminated body 19 (base material 11) can be cut up to the vicinity of 35. Therefore, the pixels 30 can be provided near the end of the base material 11 (sensor substrate 12). For example, in the radiation imaging device 1 (radiation detector 10) applied to the mammography device, the pixel area 35 can be set to a position closer to the chest wall of the subject, so that the radiation including the vicinity of the chest wall of the subject is included. It becomes possible to take an image.

[Second Embodiment]
Next, the second embodiment will be described. Since the configuration of the electrical system of the radiation imaging device 1 of the present embodiment is the same as that of the radiation imaging device 1 of the first embodiment, the description thereof will be omitted. On the other hand, FIG. 5 is an example of a plan view of the radiation detector 10 of the present embodiment as viewed from the first surface 11A side of the base material 11. 6A is an example of a sectional view taken along line AA of the radiation detector 10 in FIG. 5, and FIG. 6B is an example of a sectional view taken along line BB of the radiation detector 10 in FIG.

In the radiation detector 10 of the first embodiment, a mode in which the cable 112A is electrically connected to each of the plurality of terminal portions 60 provided on each of the pair of opposite sides of the base material 11 has been described. On the other hand, in the radiation detector 10 of the present embodiment, as shown in FIG. 5, a plurality of terminal portions 60 are provided only on one side of the base material 11, and a cable 112A is electrically connected to each of them. The point is different.

Further, as will be described in detail later, in the method of manufacturing the radiation detector 10 of the present embodiment, the portion of the laminated body 19 of the base material 11 and the reinforcing member 50 along the side of the terminal region 60A where the terminal portion 60 is provided. To disconnect. Therefore, as shown in FIG. 6A, in the radiation detector 10 of the present embodiment, the cut surface 11C of the base material 11 and the cut surface 11C of the reinforcing member 50 are end faces on the terminal region 60A side of the laminated body 19. On the other hand, as shown in FIG. 6B, in the radiation detector 10 of the present embodiment, the side surface 11D of the base material 11 and the side surface 11D of the reinforcing member 50 are end faces on the 60B side outside the terminal region in the laminated body 19.

An example of the manufacturing method of the radiation detector 10 of the present embodiment will be described with reference to FIGS. 7A to 7G.

As shown in FIG. 7A, in the step of forming the sensor substrate 12, the release layer (not shown) is formed on the support 400 in the same manner as in the step of forming the sensor substrate 12 described in the first embodiment (see FIG. 4A). The base material 11 is formed through the substrate 11. In this embodiment, since the two sides of the base material 11 (laminated body 19), which is the terminal region 60A, are cut, the alignment mark 92, which serves as a mark of the cutting position, is 3 on the first surface 11A of the base material 11. One (alignment marks 92A, 92B, 92C) is provided. Further, similarly to the first embodiment, the pixel 30 is formed in the pixel region 35 of the terminal region 60B outside the terminal region of the first surface 11A of the base material 11.

Further, as shown in FIG. 7B, in the step of forming the conversion layer, similarly to the step of forming the sensor substrate 12 described in the first embodiment (see FIG. 4A), on the pixel 30 (pixel region 35). , The conversion layer 14 is formed. Further, on the conversion layer 14 formed on the sensor substrate 12, the reflective layer 42 is provided via the adhesive layer 40, and the protective layer 46 is further provided via the adhesive layer 44.

Next, as shown in FIG. 7C, in the step of peeling the sensor substrate 12 from the support 400, the same as the step of peeling the sensor substrate 12 from the support 400 described in the first embodiment (see FIG. 4D). The sensor substrate 12 provided with the conversion layer 14 is peeled off from the support 400.

Next, as shown in FIG. 7D, in the step of providing the reinforcing member 50, the second surface 11B of the base material 11 is charged in the same manner as in the step of providing the reinforcing member 50 of the first embodiment (see FIG. 4E). The reinforcing member 50 is formed by sticking or the like via the prevention layer 54 and the adhesive 52 (see FIGS. 6A and 6B).

Next, as shown in FIGS. 7E and 7F, in the step of cutting the laminated body 19 in which the sensor substrate 12 and the reinforcing member 50 are laminated, the terminals corresponding to the outside of the pixel region 35 in the base material 11 of the laminated body 19 A portion of region 60A is cut. The cutting method of the laminated body 19 may be performed in the same manner as the step of cutting the laminated body 19 (see FIGS. 4F and 4G) in the first embodiment. In the present embodiment, the cutting device cuts the laminated body 19 along the cutting line 90A determined by the alignment mark 92A and the alignment mark 92B, and the cutting line determined by the alignment mark 92B and the alignment mark 92C. The laminate 19 is cut along 90B.

As described above, in the present embodiment, in order to cut the laminated body 19 in which the base material 11 and the reinforcing member 50 are laminated, as described above, as shown in FIG. 6A, with the cut surface 11C of the base material 11. The cut surface 50C of the reinforcing member 50 is flush with each other.

Next, as shown in FIG. 7G, in the step of electrically connecting the cable 112 to the terminal portion 60, the step of electrically connecting the cable 112 described in the first embodiment to the terminal portion 60 (see FIG. 4C). Similarly, the terminal portion 60 is formed in the terminal region 60A on the first surface 11A of the base material 11. Further, the cable 112 is thermocompression bonded to the terminal portion 60 via the connection layer 62 to electrically connect the terminal portion 60 and the connection layer 62. Further, the reinforcing member 64 (see FIG. 3A) covers the laminated body 63.

As described above, in the present embodiment, the radiation detector 10 shown in FIGS. 5 to 6B is manufactured by the steps shown in FIGS. 7A to 7G.

As described above, in the method of manufacturing the radiation detector 10 of the present embodiment, the terminal portion is cut from the terminal region outside 60B outside the pixel region 35 of the laminate 19 in which the base material 11 and the laminate 19 are laminated. The reinforcing member 50 is provided up to the end of the 60. Therefore, in the process of electrically connecting the cable 112 to the terminal portion 60, the strength of the base material 11 is reinforced by the reinforcing member 50, so that the terminal portion 60 portion is less likely to be damaged.

As described above, in the method for manufacturing the radiation detector 10 of each of the above embodiments, the flexible base material 11 is provided on the support 400, and the pixel region 35 of the base material 11 is subjected to the irradiation of radiation. A step of forming a sensor substrate 12 provided with a plurality of pixels 30 for accumulating charges and a step of peeling the sensor substrate 12 provided with the plurality of pixels 30 from the support 400 are provided. Further, the method of manufacturing the radiation detector 10 includes a step of providing a reinforcing member 50 for reinforcing the strength of the base material 11 on the second surface 11B peeled from the support 400 in the sensor substrate 12, and the reinforcing member 50 and the base material. A step of cutting a portion of the laminated body 19 in which 11 is laminated and corresponding to the outside of the pixel region 35 in the base material 11 is provided.

For example, when the pixel region 35 is formed and the pixel 30 is formed up to the vicinity of the end of the sensor substrate 12, the sensor substrate 12 bends in the step of peeling the sensor substrate 12 from the support 400 in the manufacturing process of the radiation detector 10. Therefore, there is a concern that the pixels 30 near the end of the sensor substrate 12 may be damaged. However, in the method for manufacturing the radiation detector 10 of the present embodiment, after the sensor substrate 12 is peeled off from the support 400, the laminate 19 of the base material 11 and the reinforcing member 50 is cut. According to the method for manufacturing the radiation detector 10 of the present embodiment, the laminated body 19 can be cut in the vicinity of the pixel region 35 after the sensor substrate 12 is peeled off, so that the pixels 30 are damaged up to the vicinity of the end portion of the sensor substrate 12. The suppressed pixel region 35 can be set.

Further, since the base material 11 of the sensor substrate 12 has flexibility, it is difficult to cut the base material 11 as it is. On the other hand, in the method for manufacturing the radiation detector 10 of each of the above embodiments, after the reinforcing member 50 is provided on the base material 11, the laminated body 19 of the base material 11 and the reinforcing member 50 is cut. Since the laminate 19 is thicker and more rigid than the base material 11, the laminate 19 is easier to cut than the base material 11. Therefore, according to the radiation detector 10 of each of the above embodiments, the desired range of the base material 11 (laminated body 19) can be cut without damaging the pixels 30.

Therefore, according to the method for manufacturing the radiation detector 10 of each of the above embodiments, it is possible to easily increase the proportion of the pixel region 35 in which the pixels 30 are formed in the sensor substrate 12.

The method for manufacturing the radiation detector 10 of each of the above embodiments may further include a step of providing a reinforcing layer 48 on the conversion layer 14. That is, the radiation detector 10 may include a reinforcing layer 48. FIG. 8 shows an example of a cross-sectional view of the radiation detector 10 of this modified example, which corresponds to the cross-sectional view taken along the line AA of the radiation detector 10 shown in FIG. 3A.

In the radiation detector 10 shown in FIG. 8, a reinforcing layer 48 is further provided on the conversion layer 14 covered with the protective layer 46. The reinforcing layer 48 has a higher flexural rigidity than the base material 11, and the dimensional change (deformation) with respect to the force applied in the direction perpendicular to the surface facing the conversion layer 14 is caused to the first surface 11A of the base material 11. On the other hand, it is smaller than the dimensional change with respect to the force applied in the vertical direction. Further, the thickness of the reinforcing layer 48 is thicker than that of the base material 11.

The reinforcing layer 48 is preferably made of a material having a flexural modulus of 150 MPa or more and 3000 MPa or less. The reinforcing layer 48 preferably has a higher bending rigidity than the base material 11 from the viewpoint of suppressing the bending of the base material 11. As the flexural modulus decreases, the flexural rigidity also decreases, and in order to obtain the desired flexural rigidity, the thickness of the reinforcing layer 48 must be increased, and the thickness of the entire radiation detector 10 increases. .. Considering the material of ^{the reinforcing layer 48, when trying to obtain a bending rigidity exceeding 140000 Pacm 4} , the thickness of the reinforcing layer 48 tends to be relatively thick. Therefore, when appropriate rigidity is obtained and the thickness of the entire radiation detector 10 is taken into consideration, the material used for the reinforcing layer 48 preferably has a flexural modulus of 150 MPa or more and 3000 MPa or less. Further, the flexural rigidity of the reinforcing layer 48 ^{is preferably 540 Pacm 4} or more and 140000 Pacm ⁴ or less.

Further, the coefficient of thermal expansion of the reinforcing layer 48 is preferably close to the coefficient of thermal expansion of the material of the conversion layer 14, and more preferably the ratio of the coefficient of thermal expansion of the reinforcing layer 48 to the coefficient of thermal expansion of the conversion layer 14 (reinforcing layer). The coefficient of thermal expansion of 48 / the coefficient of thermal expansion of the conversion layer 14) is preferably 0.5 or more and 2 or less. The coefficient of thermal expansion of such a reinforcing layer 48 is preferably 30 ppm / K or more and 80 ppm / K or less. For example, when the conversion layer 14 is made of CsI: Tl, the coefficient of thermal expansion is 50 ppm / K. In this case, examples of the material relatively close to the conversion layer 14 include PVC, acrylic, PET, PC, Teflon (registered trademark) and the like. Further, considering the flexural modulus described above, the material of the reinforcing layer 48 is more preferably a material containing at least one of PET and PC. Further, from the viewpoint of elasticity, the reinforcing layer 48 preferably contains a material having a yield point.

The reinforcing layer 48 is a substrate made of plastic. The plastic used as the material of the reinforcing layer 48 is preferably a thermoplastic resin for the reasons described above, and at least one of PC, PET, styrene, acrylic, polyacetase, nylon, polypropylene, ABS, engineering plastic, and polyphenylene ether can be mentioned. Be done. The reinforcing layer 48 is preferably at least one of polypropylene, ABS, engineering plastic, PET, and polyphenylene ether, and more preferably at least one of styrene, acrylic, polyacetase, and nylon. , PC and PET are more preferable. The specific characteristics, materials, and the like of the reinforcing layer 48 and the reinforcing member 50 may be the same or different.

When the conversion layer 14 is formed by the vapor phase deposition method, the conversion layer 14 is formed with an inclination that gradually decreases in thickness toward the outer edge thereof, as shown in FIGS. 8 and 3A. Will be done. In the following, the central region of the conversion layer 14 in which the thickness can be regarded as substantially constant when manufacturing errors and measurement errors are ignored is referred to as a central portion. Further, an outer peripheral region of the conversion layer 14 having a thickness of, for example, 90% or less of the average thickness of the central portion of the conversion layer 14 is referred to as a peripheral edge portion. That is, the conversion layer 14 has an inclined surface inclined with respect to the sensor substrate 12 at the peripheral edge portion. The reinforcing layer 48 shown in FIG. 8 covers the entire central portion and a part of the peripheral portion of the conversion layer 14. In other words, the outer edge of the reinforcing layer 48 is located on the inclined surface of the peripheral edge of the conversion layer 14.

The position where the reinforcing layer 48 is provided is not limited to the form shown in FIG. For example, the reinforcing layer 48 may cover the entire conversion layer 14. Further, for example, in FIG. 8, the reinforcing layer 48 is provided in a bent state along the inclined portion of the conversion layer 14, but is formed in a plate shape without bending between the inclined portion of the conversion layer 14 and the reinforcing layer 48. A space may be provided.

It is preferable that the step of providing the reinforcing layer 48 on the conversion layer 14 is performed before the sensor substrate 12 is peeled off from the support 400. In the radiation detector 10 in which the reinforcing layer 48 is provided on the conversion layer 14, the strength of the base material 11 is further reinforced.

In each of the above embodiments, the radiation detector 10 is an indirect conversion type in which the radiation is once converted into light by the conversion layer 14 and the converted light is converted into electric charges. Not limited. The radiation detector 10 may be a direct conversion type that directly converts radiation into electric charges. The direct conversion type radiation detector 10 has a function in which the sensor unit 34 receives radiation and generates an electric charge instead of the conversion layer 14 described above. Examples of the direct conversion type sensor unit 34 include a-Se (amorphous selenium) and crystal CdTe (crystal cadmium telluride).

In the case of the direct conversion type radiation detector 10, the step of forming the conversion layer 14 shown in FIG. 4B is omitted from the steps described with reference to FIGS. 4A to 4H described above. That is, after the step of forming the sensor substrate 12 shown in FIG. 4A, the step of electrically connecting the cable 112 to the terminal portion 60 shown in FIG. 4C is performed. When the protective layer 46 or the like is provided on the pixel 30 (pixel region 35), it is carried out in the step of forming the sensor substrate 12 shown in FIG. 4A.

The radiation image capturing device 1 using the radiation detector 10 of the above embodiment is used in a state of being housed in the housing 120 as shown in FIGS. 9 to 11. As an example, FIGS. 9 to 11 show a radiation imaging apparatus 1 using the radiation detector 10 of the first embodiment.

FIG. 9 shows a cross-sectional view of an example of an ISS (Irradiation Side Sampling) type radiation imaging apparatus 1 in which radiation is irradiated from the second surface 11B side of the base material 11. As shown in FIG. 9, the radiation detector 10, the power supply unit 108, and the control board 110 are provided side by side in the housing 120 in a direction intersecting the incident direction of the radiation. The radiation detector 10 is arranged in a state in which the first surface 11A side of the base material 11 on the sensor substrate 12 faces the irradiation surface 120A side of the housing 120 in which the radiation transmitted through the subject is irradiated.

Further, FIG. 10 shows a cross-sectional view of an example of a PSS (Penetration Side Sampling) type radiation imaging apparatus 1 in which radiation is irradiated from the conversion layer 14 side. As shown in FIG. 10, a radiation detector 10, a power supply unit 108, and a control board 110 are provided side by side in the housing 120 in a direction intersecting the incident direction of radiation. The radiation detector 10 is arranged in a state in which the second surface 11B side of the base material 11 on the sensor substrate 12 faces the irradiation surface 120A side of the housing 120 in which the radiation transmitted through the subject is irradiated.

The control board 110 and the drive board 200 are electrically connected by a cable 220. Further, although the description is omitted in FIGS. 9 and 10, the control board 110 and the signal processing board 300 are electrically connected by a cable.

Further, the control board 110 is connected by a power supply line 115 to a power supply unit 108 that supplies power to the image memory 106 and the control unit 100 formed on the control board 110.

A sheet 116 is further provided in the housing 120 of the radiation imaging apparatus 1 shown in FIGS. 9 and 10 on the side where the radiation transmitted through the radiation detector 10 is emitted. Examples of the sheet 116 include a copper sheet. The copper sheet is less likely to generate secondary radiation due to incident radiation, and therefore has a function of preventing scattering to the rear, that is, to the conversion layer 14 side. It is preferable that the sheet 116 covers at least the entire surface of the conversion layer 14 on the side where the radiation is emitted, and also covers the entire conversion layer 14.

Further, in the housing 120 of the radiation imaging apparatus 1 shown in FIGS. 9 and 10, a protective layer 117 is further provided on the side where radiation is incident (the irradiation surface 120A side). As the protective layer 117, a moisture-proof film such as an Alpet (registered trademark) sheet, a parylene (registered trademark) film, and an insulating sheet such as polyethylene terephthalate can be applied to the insulating sheet (film). The protective layer 117 has a moisture-proof function and an antistatic function for the pixel region 35. Therefore, the protective layer 117 preferably covers at least the entire surface of the pixel region 35 on the side where the radiation is incident, and preferably covers the entire surface of the sensor substrate 12 on the side where the radiation is incident.

As shown in the examples shown in FIGS. 9 and 10, each of the power supply unit 108 and the control board 110 is often thicker than the radiation detector 10. In such a case, as in the example shown in FIG. 11, the housing 120 in which the radiation detector 10 is provided is thicker than the thickness of the housing 120 in which each of the power supply unit 108 and the control board 110 is provided. The thickness of the portion may be thinner. In this way, when the thickness of the housing 120 in which the power supply unit 108 and the control board 110 are provided and the thickness of the housing 120 in which the radiation detector 10 is provided are different. If there is a step at the boundary between the two portions, there is a concern that the subject who comes into contact with the boundary 120B may feel uncomfortable. Therefore, it is preferable that the shape of the boundary 120B has an inclination.

This makes it possible to construct an ultra-thin portable electronic cassette according to the thickness of the radiation detector 10.

Further, for example, in this case, the material of the housing 120 is a portion of the housing 120 in which each of the power supply unit 108 and the control board 110 is provided and a portion of the housing 120 in which the radiation detector 10 is provided. It may be different. Further, for example, even if the portion of the housing 120 in which each of the power supply unit 108 and the control board 110 is provided and the portion of the housing 120 in which the radiation detector 10 is provided are configured as separate bodies. Good.

Further, as described above, the housing 120 is preferably made of a material having a low absorption rate of radiation, particularly X-rays, high rigidity, and a sufficiently high elastic modulus. The portion of the 120 corresponding to the irradiation surface 120A is made of a material having a low radiation absorption rate, high rigidity, and a sufficiently high elastic modulus, and the other parts are different from the portion corresponding to the irradiation surface 120A. It may be composed of a material, for example, a material having a lower elastic modulus than the portion of the irradiation surface 120A.

Further, in each of the above embodiments, the embodiment in which the pixels 30 are two-dimensionally arranged in a matrix as shown in FIG. 1 has been described, but the present invention is not limited to this, and for example, a one-dimensional arrangement may be used or a honeycomb. It may be an array. Further, the shape of the pixel is not limited, and it may be a rectangle or a polygon such as a hexagon. Further, it goes without saying that the shape of the pixel region 35 is not limited.

In addition, the configuration, manufacturing method, etc. of the radiation imaging device 1 and the radiation detector 10 described in each of the above embodiments are examples, and can be changed according to the situation within a range not deviating from the gist of the present invention. Needless to say.
The disclosure of Japanese Patent Application No. 2019-149303 filed August 16, 2019 is incorporated herein by reference in its entirety.
All documents, patent applications, and technical standards described herein are to the same extent as if the individual documents, patent applications, and technical standards were specifically and individually stated to be incorporated by reference. Incorporated herein by reference.

1 Radiation imaging device 10 Radiation detector 11 Base material, 11A 1st surface, 11B 2nd surface, 11C Cut surface, 11D Side surface 12 Sensor substrate 14 Conversion layer 19 Laminated body 30 Pixels 32 TFT (switching element)
34 Sensor part 35 Pixel area 36 Signal wiring 38 Scanning wiring 39 Common wiring 40 Adhesive layer 42 Reflective layer 44 Adhesive layer 46 Protective layer 48 Reinforcing layer 50 Reinforcing member, 50C Cut surface, 50D Side surface 52 Adhesive 54 Antistatic layer 60 Terminal part , 60A terminal area, 60B terminal area outside 62 Connection layer 63

Laminated body

64, 65 Reinforcing

member

90, 90A,

90B Cutting line

92, 92A to 92C Alignment mark 100 Control unit, 100A CPU, 100B memory, 100C storage unit 102 Drive unit 104 Signal processing unit 106 Image memory 108 Power supply unit 110

Control board

112, 112A, 112B, 220 Cable 115 Power supply line 116 Sheet 117 Protective layer 120 Housing, 120A irradiation surface, 120B Boundary 200

Drive board

202, 302 Connection area 210 Drive IC
300 Signal processing board 310 Signal processing IC
400 Support 410 Roller P Arrow

Claims

A step of providing a flexible base material on a support and forming a substrate provided with a plurality of pixels for accumulating charges according to the irradiated radiation in the pixel region of the base material.
A step of peeling the substrate provided with the plurality of pixels from the support,
A step of providing a reinforcing member for reinforcing the strength of the base material on the surface of the substrate peeled off from the support, and
A step of cutting a portion of the laminated body in which the reinforcing member and the base material are laminated, which corresponds to the outside of the pixel region of the base material.
A method of manufacturing a radiation detector equipped with.
The cut surface of the reinforcing member and the base material is flush with each other.
The method for manufacturing a radiation detector according to claim 1.
The substrate has a terminal area provided with a terminal portion for electrically connecting a cable on a surface provided with the plurality of pixels.
In the step of cutting the base material, a portion other than the terminal region is cut.
The method for manufacturing a radiation detector according to claim 1 or 2.
Prior to the step of peeling the substrate from the support,
A step of electrically connecting a cable to the terminal portion is further provided.
The method for manufacturing a radiation detector according to claim 3.
After the step of cutting the substrate,
A step of providing a terminal portion for electrically connecting the cable to the surface provided with the plurality of pixels along the side of the substrate on the side where the base material is cut is further provided.
The method for manufacturing a radiation detector according to claim 1 or 2.
The reinforcing member has higher rigidity than the base material.
The method for manufacturing a radiation detector according to any one of claims 1 to 5.
The reinforcing member has a flexural modulus of 500 MPa or more and 3000 MPa or less.
The method for manufacturing a radiation detector according to any one of claims 1 to 6.
The reinforcing member is a member made of at least one of polycarbonate and polyethylene terephthalate.
The method for manufacturing a radiation detector according to any one of claims 1 to 7.
The base material has a mark on the surface provided with the plurality of pixels.
In the step of cutting the laminate, the position corresponding to the mark is cut.
The method for manufacturing a radiation detector according to any one of claims 1 to 8.
Between the step of forming the substrate and the step of peeling the substrate from the support
A step of forming a conversion layer for converting the radiation into light is further provided on the surface of the base material provided with the plurality of pixels.
Each of the plurality of pixels accumulates an electric charge corresponding to the light converted by the conversion layer.
The method for manufacturing a radiation detector according to any one of claims 1 to 9.
Each of the plurality of pixels includes a sensor unit that receives the radiation and generates an electric charge, and accumulates the electric charge generated by the sensor unit.
The method for manufacturing a radiation detector according to any one of claims 1 to 9.