Patent Description:
Radiographic imaging devices that perform radiographic imaging for medical diagnostic purposes are known. In such radiographic imaging devices, a radiation detector is employed to generate radiographic images by detecting radiation that has passed through an imaging subject (see, for example, Japanese Patent Application Laid-Open (<CIT>and <CIT>).

Such radiation detectors may include a conversion layer such as a scintillator to convert radiation into light, and a substrate including a pixel region on a base member, the pixel region being provided with plural pixels that accumulate charges generated in response to light converted by the conversion layer. The use of a flexible base member as the base member of the substrate of such a radiation detector is known. Employing a flexible base member may for example enable a reduction in weight of the radiographic imaging device (radiation detector) or facilitate imaging of the imaging subject.

However, the radiation detector may be handled on its own during processes to manufacture the radiographic imaging device and the like. When handling the radiation detector on its own, there is a concern that the conversion layer might detach from the substrate, for example due to the effects of bending of the flexible substrate.

In the technology described in <CIT>, a conversion layer is provided with an electromagnetic shielding layer that covers an opposite-side surface of the conversion layer to a surface on a substrate side. In the technology described in <CIT>, a support body that supports a conversion layer is provided on an opposite-side surface of the conversion layer to a surface on a substrate side. However, the technology described in <CIT> and <CIT> do not consider cases in which a radiation detector is handled on its own. Accordingly, the electromagnetic shielding layer of <CIT> and the support body of <CIT> may not be able to suppress detachment of the conversion layer from the substrate when the radiation detector is handled on its own. <CIT> discloses a radiation detector that may be detached to enable repairs to be performed In particular, it discloses a radiation detector disposed in a first compartment, which is surrounded by a first plate, a frame and a chassis. A first base plate, which supports the radiation detector thereon, is fixed by a first adhesive layer to an inner surface of the first plate. A second base plate, which supports the radiation detector thereon and which also reinforces the scintillator, is fixed by a second adhesive layer to a surface of the chassis, which faces toward the first plate. A support layer and the second base plate are bonded to each other by a double-sided pressure-sensitive adhesive tape. The photoelectric transducer board and the first base plate are bonded to each other by a double-sided pressure-sensitive adhesive tape which includes a pressure-sensitive adhesive that can be peeled off. The radiation detector can therefore easily be detached from the radiation detecting apparatus so as to enable repairs.

The present invention provides a manufacturing method that is better capable of suppressing breakage of a conversion layer when a radiation detector is on its own than in cases in which consideration is not given to the material of a reinforcement substrate provided to an opposite-side surface of a conversion layer to a surface on a substrate side.

According to an aspect of the present invention, there is provided a manufacturing method for a radiation detector as claimed in claim <NUM>.

The manufacturing method may further include, prior to the process of affixing the reinforcement substrate, a process of connecting one end of flexible wiring, which is connected to a circuit section that reads out the charges accumulated in the plural pixels, to the substrate.

The present disclosure may better suppress breakage of the conversion layer when the radiation detector is on its own, than in cases in which consideration is not given to the material of the reinforcement substrate provided to the opposite-side surface of the conversion layer to the surface on the substrate side.

Detailed explanation follows regarding exemplary radiation detectors that may be manufactured according to embodiments of the present invention, with reference to the drawings.

The present exemplary radiation detector not covered by the claimed invention has a function of outputting image information expressing radiographic images of an imaging subject by detecting radiation that has passed through the imaging subject. The radiation detector includes a thin film transistor (TFT) substrate and a conversion layer configured to convert radiation into light (a TFT substrate <NUM> and a conversion layer <NUM> of a radiation detector <NUM>, see <FIG>).

First, explanation follows regarding an example of configuration of the TFT substrate <NUM> of the present exemplary radiation detector, with reference to <FIG>. Note that the TFT substrate <NUM> of the present exemplary radiation detector is a substrate in which a pixel array <NUM> including plural pixels <NUM> is formed in a pixel region <NUM> of a base member <NUM>. Accordingly, the expression "pixel region <NUM>" is synonymous with the "pixel array <NUM>". The TFT substrate <NUM> of the present exemplary radiation detector is an example of a substrate of technology disclosed herein.

The base member <NUM> is made of resin, and is flexible. For example, the base member <NUM> is a resin sheet including a plastic such as polyimide. The thickness of the base member <NUM> may be any thickness that enables the desired flexibility to be obtained, set according to the hardness of the material, the size of the TFT substrate <NUM>, and the like. For example, in cases in which the base member <NUM> is configured by a resin sheet, the base member <NUM> should have a thickness of from <NUM> to <NUM>, and more preferably has a thickness of from <NUM> to <NUM>.

Note that the base member <NUM> has characteristics capable of withstanding manufacture of the pixels <NUM>, as will be described in detail later, and in the present exemplary radiation detector, has characteristics capable of withstanding the manufacture of amorphous silicon TFTs (a-Si TFTs). Preferable characteristics of the base member <NUM> are a coefficient of thermal expansion in a range of from <NUM> to <NUM> that is similar to that of an silicon (Si) wafer (for example ± <NUM> ppm/K), and more specifically preferably no greater than <NUM> ppm/K. The heat shrinkage ratio of the base member <NUM> in a machine direction (MD) at <NUM> and at a thickness of <NUM> is preferably a heat shrinkage ratio of no greater than <NUM>%. Moreover, the modulus of elasticity of the base member <NUM> preferably does not have a transition point in a temperature region of from <NUM> to <NUM>, as is typical of an ordinary polyimide, and preferably has a modulus of elasticity at <NUM> of no less than <NUM> GPa.

Moreover, as illustrated in <FIG>, the base member <NUM> of the present exemplary radiation detector preferably includes a fine particle layer <NUM> containing inorganic fine particles 11P having a mean particle size of from <NUM> to <NUM> on an opposite-side surface to the side provided with the conversion layer <NUM>. XENOMAX (registered trademark) is a specific example of a resin sheet having such characteristics.

Note that the thickness discussed in the present exemplary radiation detector is measured using a micrometer. The coefficient of thermal expansion is measured according to JIS K7197:<NUM>. In this measurement, test pieces are cut from a main face of the base member <NUM> while changing the angle thereof by <NUM> degrees each time, the coefficient of thermal expansion is measured for each of the cut test pieces, and the highest value obtained is taken to be the coefficient of thermal expansion of the base member <NUM>. The measurements of the coefficient of thermal expansion in the machine direction (MD) and a transverse direction (TD) are performed at <NUM> intervals over a range of from -<NUM> to <NUM> with ppm/°C converted into ppm/K. A TMA4000S instrument made by MAC Science Co. is employed to measure the coefficient of thermal expansion using a sample length of <NUM>, a sample width of <NUM>, an initial load of <NUM>/mm<NUM>, a rate of temperature increase of <NUM>/min, and an argon atmosphere. The modulus of elasticity is measured according to JIS K7171:<NUM>. Note that in this measurement, test pieces are cut from a main face of the base member <NUM> while changing the angle thereof by <NUM> degrees each time, a stretch test is performed on each of the cut test pieces, and the highest value obtained is taken to be the modulus of elasticity of the base member <NUM>.

Each of the pixels <NUM> includes a sensor section <NUM> that accumulates an charges generated in response to light converted by the conversion layer, and a switching element <NUM> that reads the accumulated charges from the sensor section <NUM>. As an example, in the present exemplary radiation detector, a thin film transistor (TFT) is employed as the switching element <NUM>. The switching element <NUM> is thus referred to as the "TFT <NUM>" hereafter.

The plural pixels <NUM> are arranged along one direction (a scan line direction corresponding to the lateral direction in <FIG>, hereafter also referred to as the "row direction") and along a direction intersecting the row direction (a signal line direction corresponding to the longitudinal direction in <FIG>, hereafter also referred to as the "column direction") to form a two-dimensional pattern in the pixel region <NUM> of the TFT substrate <NUM>. Although the array of the pixels <NUM> is simplified in the illustration of <FIG>, for example <NUM> × <NUM> of the pixels <NUM> are arranged along the row direction and the column direction.

The radiation detector <NUM> is further provided with plural scan lines <NUM> to control switching states (ON and OFF states) of the TFTs <NUM>, and plural signal lines <NUM> that intersect the plural scan lines <NUM> and correspond to each column of the pixels <NUM> to read the accumulated charges from the sensor sections <NUM>. Each of the plural scan lines <NUM> is connected to a drive section <NUM> (see <FIG>) provided externally to the radiation detector <NUM> through a connection region <NUM> (see <FIG> and <FIG>) provided on the TFT substrate <NUM>, so as to allow a flow of control signals output from the drive section <NUM> to control the switching states of the TFTs <NUM>. Moreover, each of the plural signal lines <NUM> is connected to a signal processing section <NUM> (see <FIG>) provided externally to the radiation detector <NUM> through a connection region <NUM> (see <FIG> and <FIG>) provided on the TFT substrate <NUM>, such that charges read from the pixels <NUM> are output to the signal processing section <NUM>.

Common lines <NUM> are provided along the wiring direction of the signal lines <NUM> to the sensor sections <NUM> of the corresponding pixels <NUM> in order to apply a bias voltage to the corresponding pixels <NUM>. Each of the common lines <NUM> is connected to a bias power source external to the radiation detector <NUM> through a pad (not illustrated in the drawings) provided on the TFT substrate <NUM>, such that the bias voltage from the bias power source is applied to the corresponding pixels <NUM>.

In the present exemplary radiation detector <NUM>, the conversion layer is formed on the TFT substrate <NUM>. <FIG> is a plan view illustrating the radiation detector <NUM> as viewed from a side formed with the conversion layer <NUM>. <FIG> is a cross-section of the radiation detector <NUM> illustrated in <FIG>, as sectioned along line A-A. In the following explanation, reference to "on top" with respect to the structure of the radiation detector <NUM> refers being on top in a positional relationship referenced against the TFT substrate <NUM> side. For example, the conversion layer <NUM> is provided on top of the TFT substrate <NUM>.

As illustrated in <FIG> and <FIG>, the conversion layer <NUM> of the present exemplary radiation detector is provided on top of a region configuring a portion of a first surface 12A of the TFT substrate <NUM> that includes the pixel region <NUM>. Thus, the conversion layer <NUM> of the present exemplary radiation detector is not provided on top of a region corresponding to an outer peripheral portion of the first surface 12A of the TFT substrate <NUM>. The first surface 12A of the present exemplary radiation detector is an example of a pixel region-provided surface of the present disclosure.

In the present exemplary radiation detector, a scintillator containing cesium iodide (CsI) is employed as an example of the conversion layer <NUM>. For example, the scintillator preferably contains thallium-doped cesium iodide (CsLTl) or sodium-doped cesium iodide (CsI:Na) that has light emission spectra of from <NUM> to <NUM> when irradiated with X-rays. Note that the peak light emission wavelength of CsI:Tl in the visible light region is <NUM>.

In the radiation detector <NUM> of the present exemplary radiation detector, the conversion layer <NUM> is formed from strip shaped columnar crystals (not illustrated in the drawings) formed directly on top of the TFT substrate <NUM> using a vapor phase deposition method such as a vacuum deposition method, a sputtering method, or a chemical vapor deposition (CVD) method. As an example of the formation method of the conversion layer <NUM>, in cases in which CsETl is used as the conversion layer <NUM>, a vacuum deposition method may be applied in which the CsI:Tl is heated and vaporized, for example using a resistance heating crucible under environmental conditions of a vacuum of from <NUM> Pa to <NUM> Pa, and the CsI:Tl is deposited on top of the TFT substrate <NUM> with the TFT substrate <NUM> at a temperature between room temperature (<NUM>) and <NUM>. The thickness of the conversion layer <NUM> is preferably from <NUM> to <NUM>.

In the present exemplary radiation detector, as illustrated in <FIG> as an example, a buffer layer <NUM> is provided between the TFT substrate <NUM> and the conversion layer <NUM>. The buffer layer <NUM> has a function of buffering a difference between the coefficient of thermal expansion of the conversion layer <NUM> and the coefficient of thermal expansion of the base member <NUM>. Note that although a configuration differing from that of the radiation detector <NUM> of the exemplary radiation detector of the present disclosure may be made in which the buffer layer <NUM> is not provided, providing the buffer layer <NUM> is more preferable the greater the difference between the coefficient of thermal expansion of the conversion layer <NUM> and the coefficient of thermal expansion of the base member <NUM>. For example, in cases in which XENOMAX (registered trademark) is employed for the base member <NUM>, the difference to the coefficient of thermal expansion of the conversion layer <NUM> is greater than it would be with other materials, and so the buffer layer <NUM> is preferably provided as in the radiation detector <NUM> illustrated in <FIG>. A polyimide (PI) film or a Parylene (registered trademark) film may be employed as the buffer layer <NUM>.

A protective layer <NUM> has a function of protecting the conversion layer <NUM> from moisture such as humidity. Examples of materials that may be employed as the material of the protective layer <NUM> include organic films such as single layer films or stacked films of polyethylene terephthalate (PET), polyphenylene sulfide (PPS), oriented polypropylene (OPP), PEN (polyethylene naphthalate), PI, and the like. Moreover, an ALPET (registered trademark) sheet in which aluminum, for example a bonded aluminum foil, is stacked on an insulating sheet (film) such as PET may be employed as the protective layer <NUM>.

A stacked body <NUM> configured by stacking the TFT substrate <NUM>, the buffer layer <NUM>, the conversion layer <NUM>, and the protective layer <NUM> includes a first surface 19A, this being a surface on the side of the conversion layer <NUM>. A reinforcement substrate <NUM> is provided on the first surface 19A using an adhesion layer <NUM> or the like.

The reinforcement substrate <NUM> has a higher rigidity than the base member <NUM>, such that dimensional change (deformation) with respect to force applied in a direction perpendicular to a surface opposing the conversion layer <NUM> is smaller than the dimensional change with respect to force applied in a direction perpendicular to the first surface 12A of the TFT substrate <NUM>. The thickness of the reinforcement substrate <NUM> of the present exemplary radiation detector is also greater than the thickness of the base member <NUM>. Note that the rigidity referred to here refers to the difficulty of bending the reinforcement substrate <NUM> and the base member <NUM>, encompassing the thicknesses of the reinforcement substrate <NUM> and the base member <NUM>, with bending becoming more difficult the greater the rigidity.

The reinforcement substrate <NUM> of the present exemplary radiation detector is a substrate containing a material having a yield point. In the present exemplary radiation detector, the "yield point" refers to the point at which yielding occurs on a curve expressing the relationship between stress and strain in the phenomenon in which stress suddenly decreases when the material is applied with tension. Examples of resins having a yield point are generally hard resins with high viscosity, and soft resins with high viscosity and moderate strength. At least one out of polycarbonate (PC) or polyamide is an example of a hard resin with high viscosity. At least one out of high density polyethylene or polypropylene is an example of a soft resin with high toughness and moderate strength.

The reinforcement substrate <NUM> of the present exemplary radiation detector preferably has a bending elastic modulus of from <NUM> MPa to <NUM> MPa. The bending elastic modulus is, for example, measured according to the method set out in JIS K7171:<NUM>. If the bending elastic modulus is lower than this, the thickness of the reinforcement substrate <NUM> has to be increased to obtain rigidity. From the perspective of suppressing the thickness, the bending elastic modulus of the reinforcement substrate <NUM> is more preferably from <NUM> MPa to <NUM> MPa.

The coefficient of thermal expansion (CTE) of the reinforcement substrate <NUM> of the present exemplary radiation detector is preferably close to the coefficient of thermal expansion of the material of the conversion layer <NUM>, and more preferably the ratio of the coefficient of thermal expansion of the reinforcement substrate <NUM> with respect to the coefficient of thermal expansion of the conversion layer <NUM> is from <NUM> to <NUM>. For example, in cases in which CsI:Tl is employed as the material of the conversion layer <NUM>, the coefficient of thermal expansion thereof is <NUM> ppm/K. In such cases, examples of materials that may be employed for the reinforcement substrate <NUM> include polyvinyl chloride (PVC) with a coefficient of thermal expansion of from <NUM> ppm/K to <NUM> ppm/K, acrylic with a coefficient of thermal expansion of from <NUM> ppm/K to <NUM> ppm/K, PET with a coefficient of thermal expansion of from <NUM> ppm/K to <NUM> ppm/K, PC with a coefficient of thermal expansion of <NUM> ppm/K, and TEFLON (registered trademark) with a coefficient of thermal expansion of from <NUM> ppm/K to <NUM> ppm/K. In consideration of the bending elastic modulus described above, the material of the reinforcement substrate <NUM> is more preferably a material containing at least one out of PET or PC.

As illustrated in <FIG> and <FIG>, the reinforcement substrate <NUM> of the present exemplary radiation detector is provided over a wider region of the first surface 12A of the TFT substrate <NUM> than a region provided with the conversion layer <NUM>. As illustrated in <FIG> and <FIG>, an end portion of the reinforcement substrate <NUM> projects out further toward an outer side (an outer peripheral portion side of the TFT substrate <NUM>) than an outer peripheral portion of the conversion layer <NUM>.

As illustrated in <FIG>, the connection regions <NUM> are provided in the outer peripheral portion of the TFT substrate <NUM>. Flexible cables <NUM>, described in detail later, are connected to the connection regions <NUM>. The flexible cables <NUM> are connected to at least one out of the drive section <NUM> or the signal processing section <NUM> (see <FIG> for both). The drive section <NUM> and the signal processing section <NUM> of the present exemplary radiation detector are examples of circuit sections of the present disclosure. <FIG> is a plan view illustrating an example of a state in which the drive section <NUM> and the signal processing section <NUM> are connected to the radiation detector <NUM> as viewed from the first surface 12A side of the TFT substrate <NUM>.

As illustrated in the example of <FIG>, the flexible cables <NUM> are electrically connected to the connection regions <NUM> of the TFT substrate <NUM>. Note that in the present exemplary radiation detector, unless specifically stated otherwise, "connection" in the context of components including the flexible cables <NUM> that are described as "cables" refers to an electrical connection. Note that the flexible cables <NUM> include conductive signal lines (not illustrated in the drawings), such signal lines being electrically connected by being connected to the connection regions <NUM>. The flexible cables <NUM> of the present exemplary radiation detector are an example of flexible wiring of the present disclosure. Hereafter, "cables" are understood to be flexible (have flexibility).

One ends of plural of the flexible cables <NUM> (four in <FIG>) are thermally compressed onto the corresponding connection region <NUM> (43A) of the TFT substrate <NUM>. These flexible cables <NUM> have a function of connecting the drive section <NUM> and the scan lines <NUM> (see <FIG>) together. The plural signal lines (not illustrated in the drawings) included in the flexible cables <NUM> are connected to the scan lines <NUM> (see <FIG>) of the TFT substrate <NUM> through the connection region <NUM>.

The other ends of the flexible cables <NUM> are thermally compressed onto a connection region <NUM> (243A) provided in a region at an outer periphery of a drive substrate <NUM>. The plural signal lines (not illustrated in the drawings) included in the flexible cables <NUM> are connected to drive components <NUM>, these being circuits, elements, and the like mounted on the drive substrate <NUM>, through the connection region <NUM>.

<FIG> illustrates an example of a state in which nine drive components <NUM> (250A to <NUM>) are mounted on the drive substrate <NUM>. As illustrated in <FIG>, the drive components <NUM> of the present exemplary radiation detector are arranged along an intersecting direction X that intersects a bending direction Y, this being a direction along a side corresponding to the connection region <NUM> (43A) of the TFT substrate <NUM>.

The drive substrate <NUM> of the present exemplary radiation detector is a flexible printed circuit board (PCB), configuring what is referred to as a flexible substrate. The drive components <NUM> mounted on the drive substrate <NUM> are primarily components involved in digital signal processing (referred to hereafter as "digital system components"). Specific examples of the drive components <NUM> include digital buffers, bypass capacitors, pull-up and pull-down resistors, damping resistors, and electromagnetic compatibility (EMC) chip components. Note that the drive substrate <NUM> does not necessary have to be a flexible substrate, and may be a non-flexible, rigid substrate, as described later.

Digital system components tend to have a smaller surface area (size) than analog system components, described later. Moreover, digital system components tend to be less susceptible to being strongly affected by electrical interference, in other words noise, than analog system components. Accordingly, in the present exemplary radiation detector, the drive substrate <NUM> mounted with the drive components <NUM> is configured on a side that bends accompanying bending of the TFT substrate <NUM> when the TFT substrate <NUM> bends.

Drive circuit sections <NUM> are also mounted on the flexible cables <NUM> connected to the drive substrate <NUM>. The drive circuit sections <NUM> are connected to the plural signal lines (not illustrated in the drawings) included in the flexible cables <NUM>.

In the present exemplary radiation detector, the drive section <NUM> is implemented by the drive components <NUM> mounted on the drive substrate <NUM> and the drive circuit sections <NUM>. The drive circuit sections <NUM> are integrated circuits (IC) that include different circuits to those of the drive components <NUM> mounted on the drive substrate <NUM> out of the various circuits and elements used to implement the drive section <NUM>.

In this manner, in the radiation detector <NUM>, the TFT substrate <NUM> and the drive substrate <NUM> are electrically connected by the flexible cables <NUM> in order to connect the drive section <NUM> and the scan lines <NUM> together.

One ends of plural of the flexible cables <NUM> (four in <FIG>) are thermally compressed onto the corresponding connection region <NUM> (43B) of the TFT substrate <NUM>.

The plural signal lines (not illustrated in the drawings) included in these flexible cables <NUM> are connected to the signal lines <NUM> (see <FIG>) through the connection region <NUM>. The flexible cables <NUM> have a function of connecting the signal processing section <NUM> and the signal lines <NUM> (see <FIG>) together.

The other ends of the flexible cables <NUM> are electrically connected to connectors <NUM> provided in a connection region <NUM> (243B) of a signal processing substrate <NUM>. The plural signal lines (not illustrated in the drawings) included in the flexible cables <NUM> are connected to signal processing components <NUM>, these being circuits, elements, and the like mounted on the signal processing substrate <NUM>, through the connectors <NUM>. Examples of the connectors <NUM> include connectors with zero insertion force (ZIF) structures, and connectors with non-ZIF structures. As an example, <FIG> illustrates a state in which nine of the signal processing components <NUM> (350A to <NUM>) are mounted on the signal processing substrate <NUM>. As illustrated in <FIG>, the signal processing components <NUM> of the present exemplary radiation detector are disposed along the intersecting direction X, this being a direction running along the connection region <NUM> (43B) of the TFT substrate <NUM>.

Note that the signal processing substrate <NUM> of the present exemplary radiation detector is a non-flexible PCB substrate, namely what is referred to as a rigid substrate. Accordingly, the thickness of the signal processing substrate <NUM> is greater than the thickness of the drive substrate <NUM>. The signal processing substrate <NUM> also has a higher rigidity than the drive substrate <NUM>.

The signal processing components <NUM> mounted on the signal processing substrate <NUM> are primarily components employed in analog signal processing (referred to hereafter as analog system components). Specific examples of the signal processing components <NUM> include operational amplifiers, analog-digital converters (ADCs), digital-analog converters (DACs), and power source ICs. The signal processing components <NUM> of the present exemplary radiation detector also include power source coils and high-capacity smoothing capacitors, these being comparatively large components.

As described above, the analog system components tend to have a larger surface area (size) than the digital system components. Furthermore, the analog system components tend to be more susceptible to the effects of electrical interference, in other words noise, than the digital system components. Accordingly, in the present exemplary radiation detector, the signal processing substrate <NUM> mounted with the signal processing components <NUM> is configured on a side of the substrate that does not bend (is not affected by bending) when the TFT substrate <NUM> bends.

Signal processing circuit sections <NUM> are mounted on the flexible cables <NUM> connected to the signal processing substrate <NUM>. The signal processing circuit sections <NUM> are connected to the plural signal lines (not illustrated in the drawings) included in the flexible cables <NUM>.

In the present exemplary radiation detector, the signal processing section <NUM> is implemented by the signal processing components <NUM> mounted on the signal processing substrate <NUM> and by the signal processing circuit sections <NUM>. Out of the various circuits and elements used to implement the signal processing section <NUM>, the signal processing circuit sections <NUM> are ICs including different circuits to the signal processing components <NUM> mounted on the signal processing substrate <NUM>.

In this manner, in the radiation detector <NUM>, the TFT substrate <NUM> and the signal processing substrate <NUM> are electrically connected by the flexible cables <NUM> so as to connect the signal processing section <NUM> and the respective signal lines <NUM> together.

As in the example illustrated in <FIG>, the radiation detector <NUM> further includes a spacer <NUM> provided between the reinforcement substrate <NUM> and the first surface 12A of the TFT substrate <NUM> so as to seal a side face of the conversion layer <NUM>. The flexible cables <NUM>, an anti-moisture agent <NUM>, and an adhesion layer <NUM> are sandwiched between the spacer <NUM> and the TFT substrate <NUM>.

The method of providing the spacer <NUM> is not particularly limited, and for example the spacer <NUM> may be affixed to the adhesion layer <NUM> at an end portion of the reinforcement substrate <NUM>, and the reinforcement substrate <NUM> may then be affixed to the TFT substrate <NUM> in a state in which the spacer <NUM> has been provided to the reinforcement substrate <NUM> and in a state in which the stacked body <NUM>, the flexible cables <NUM>, the anti-moisture agent <NUM>, and the adhesion layer <NUM> have been provided to the TFT substrate <NUM>, such that the spacer <NUM> is thus provided between the TFT substrate <NUM> and the reinforcement substrate <NUM>. Note that the width of the spacer <NUM> (in a direction intersecting the stacking direction of the stacked body <NUM>) is not limited to the example illustrated in <FIG>. For example, the width of the spacer <NUM> may be increased to a position closer to the conversion layer <NUM> than that illustrated in the example of <FIG>. Alternatively, the spacer <NUM> may be formed by caulking with resin, ceramic, or the like on the first surface 12A of the TFT substrate <NUM>.

A protective film <NUM> that has a function of protecting from moisture such as humidity is provided on a second surface 12B of the TFT substrate <NUM> of the present exemplary radiation detector. Materials configuring the protective film <NUM> may, for example, be the same as the materials employed for the protective layer <NUM>.

Explanation follows regarding an example of a manufacturing method of the present exemplary radiation detector <NUM>. The example of a manufacturing method of the present exemplary radiation detector <NUM> according on an embodiment is explained with reference to <FIG> and <FIG>.

The reinforcement substrate <NUM> is pre-prepared in a desired size appropriate for the radiation detector <NUM>, in a state coated with the adhesion layer <NUM> and provided with the spacer <NUM> on the adhesion layer <NUM>.

As illustrated in <FIG>, the base member <NUM> is formed on a support body <NUM> such as a glass substrate with a greater thickness than the base member <NUM> with a separation layer (not illustrated in the drawings) interposed therebetween. In cases in which the base member <NUM> is formed by a lamination method, a sheet configuring the base member <NUM> is affixed onto the support body <NUM>. A surface corresponding to the second surface 12B of the TFT substrate <NUM> of the base member <NUM> contacts the separation layer (not illustrated in the drawings).

The plural pixels <NUM> are then formed in the pixel region <NUM> of the base member <NUM>. Note that as an example, in the present embodiment, the plural pixels <NUM> are formed in the pixel region <NUM> of the base member <NUM> with an undercoat layer (not illustrated in the drawings) employing SiN or the like interposed therebetween.

The conversion layer <NUM> is then formed on top of the pixel region <NUM>. In the present embodiment, first the buffer layer <NUM> is formed in a region of the first surface 12A of the TFT substrate <NUM> to be provided with the conversion layer <NUM>. Then, the conversion layer <NUM> is formed on top of the TFT substrate <NUM>, and more specifically directly on top of the buffer layer <NUM>, by columnar crystals of CsI directly formed using a vapor phase deposition method such as a vacuum deposition method, a sputtering method, or a chemical vapor deposition (CVD) method. When this is performed, the side of the conversion layer <NUM> contacting the pixels <NUM> corresponds to the start side in the growth direction of the columnar crystals.

Note that in cases in which the CsI conversion layer <NUM> is directly provided on top of the TFT substrate <NUM> using a vapor phase deposition method in this manner, the opposite-side surface of the conversion layer <NUM> to the side contacting the TFT substrate <NUM> may, for example, be provided with a reflective layer (not illustrated in the drawings) having a function of reflecting light converted by the conversion layer <NUM>. Such a reflective layer may be directly provided to the conversion layer <NUM>, or may be provided with a cohesion layer or the like interposed therebetween. An organic material is preferably employed as the material of the reflective layer, and for example a material employing at least one material out of white PET, TiO<NUM>, Al<NUM>O<NUM>, foamed white PET, a highly reflective polyester sheet, or a specular reflective aluminum is preferably employed. In particular, from the perspective of reflectivity, a white PET material is preferably employed. Note that a highly reflective polyester sheet is a sheet (film) having a multi-layered structure of plural overlapping thin polyester sheets.

In cases in which a CsI scintillator is employed as the conversion layer <NUM>, the conversion layer <NUM> may be formed on the TFT substrate <NUM> using a different method to that of the present embodiment. For example, vapor deposition of CsI on an aluminum sheet or the like may be performed using a vapor phase deposition method, and the conversion layer <NUM> may be formed on the TFT substrate <NUM> by affixing the side of the CsI that does not contact the aluminum sheet and the pixels <NUM> of the TFT substrate <NUM> together using an adhesive sheet or the like. In such cases, a product obtained by covering the overall conversion layer <NUM> including the aluminum sheet with a protective film is preferably affixed to the pixel region <NUM> of the TFT substrate <NUM>. Note that in such cases, the side of the conversion layer <NUM> contacting the pixel region <NUM> configures a growth direction tip end side of the columnar crystals.

Unlike the radiation detector <NUM> of the present embodiment, GOS (Gd<NUM>O<NUM>S:Tb) or the like may be employed in place of CsI as the conversion layer <NUM>. In such cases, a sheet on which GOS has been distributed using a resin binder or the like may be affixed to a support body formed from white PET or the like using an adhesion layer or the like, and the side of the GOS that is not affixed to the support body may be affixed to the pixel region <NUM> of the TFT substrate <NUM> using an adhesive sheet or the like to form the conversion layer <NUM> on the TFT substrate <NUM>. Note that the efficiency of radiation to visible light conversion is greater when CsI is employed than when GOS is employed for the conversion layer <NUM>.

The flexible cables <NUM> are then thermally compressed onto the connection regions <NUM> (43A and 43B) of the TFT substrate <NUM>, to electrically connect the plural signal lines (not illustrated in the drawings) included in the flexible cables <NUM> to the connection regions <NUM> (43A and 43B) of the TFT substrate <NUM>.

The flexible cables <NUM> are then thermally compressed onto the connection region <NUM> (243A) of the drive substrate <NUM> to electrically connect the plural signal lines (not illustrated in the drawings) included in the flexible cables <NUM> to the drive components <NUM> mounted on the drive substrate <NUM>.

The pre-prepared reinforcement substrate <NUM> provided with the spacer <NUM> is then affixed to the TFT substrate <NUM> on which the conversion layer <NUM> has been formed and to which the flexible cables <NUM> have been connected, thus sealing the conversion layer <NUM>. Note that this affixing may be performed under atmospheric pressure or under a reduced pressure (in a vacuum). Reduced pressure is preferable in order to suppress air and the like from being incorporated between affixed components.

The radiation detector <NUM> is then separated from the support body <NUM> as illustrated in <FIG>. When separating by mechanical separation, as in the example illustrated in <FIG>, separation is started at an opposite edge of the TFT substrate <NUM> to an edge to which the flexible cables <NUM> are connected, and the TFT substrate <NUM> is gradually peeled away from the support body <NUM> in the arrow D direction in <FIG> on progression toward from the start edge toward the edge to which the flexible cables <NUM> are connected. The radiation detector <NUM> is thereby obtained in a state in which the flexible cables <NUM> are connected thereto by performing such mechanical separation.

Note that the edge from which separation is started is preferably on edge intersecting the longest edge of the TFT substrate <NUM> as viewed in plan view. In other words, an edge along the bending direction Y in which bending occurs during separation is preferably the longest edge. In the present embodiment, the edge to which the drive substrate <NUM> is connected through the flexible cables <NUM> is longer than the edge to which the signal processing substrate <NUM> is connected through the flexible cables <NUM>. Accordingly, separation is started at the opposite edge to the edge provided with the connection region <NUM> (43B).

In the present embodiment, after separating the TFT substrate <NUM> from the support body <NUM>, the flexible cables <NUM> of the radiation detector <NUM> and the connectors <NUM> of the signal processing substrate <NUM> are electrically connected together. The radiation detector <NUM> of the example of the present exemplary embodiment illustrated in <FIG> is manufactured in this manner.

Note that the exemplary embodiment is not limited thereto, and the above mechanical separation may be performed after the flexible cables <NUM> of the radiation detector <NUM> and the connectors <NUM> of the signal processing substrate <NUM> have been electrically connected together.

During mechanical separation, as illustrated in <FIG> and <FIG>, the drive substrate <NUM> of the radiographic imaging device <NUM> of the present exemplary embodiment also bends in response to the bending of the TFT substrate <NUM> since the drive substrate <NUM> is a flexible substrate.

Note that when separating the TFT substrate <NUM> from the support body <NUM>, due to the flexibility of the base member <NUM>, the TFT substrate <NUM> bends readily. When the TFT substrate <NUM> bends greatly, there is a concern of the conversion layer <NUM> detaching from the TFT substrate <NUM> as a result of the TFT substrate <NUM> bending greatly. In particular, the end portion of the conversion layer <NUM> is liable to detach from the TFT substrate <NUM>. Moreover, there is a concern of the conversion layer <NUM> detaching from the TFT substrate <NUM> due to bending of the TFT substrate <NUM> not only when separating the TFT substrate <NUM> from the support body <NUM>, but also when the radiation detector <NUM> is handled on its own such as during manufacturing processes of the radiographic imaging device <NUM>. To address this, in the radiation detector <NUM>, the reinforcement substrate <NUM> that contains a material having a yield point and that has a higher rigidity than the base member <NUM> is provided to the first surface 19A, this being an opposite-side surface to the first surface 12A of the TFT substrate <NUM>. Accordingly, the radiation detector <NUM> is capable of suppressing sharp bending of the TFT substrate <NUM>, enabling the conversion layer <NUM> to be suppressed from detaching from the TFT substrate <NUM>.

Next, explanation follows regarding a second exemplary radiation detector not covered by the claimed invention. <FIG> is a cross-section illustrating an example of a radiation detector <NUM> of the present exemplary radiation detector.

As illustrated in <FIG>, in the radiation detector <NUM> of the present exemplary radiation detector, a reinforcement member <NUM> is provided to the second surface 12B of the TFT substrate <NUM>. In the radiation detector <NUM> of the present exemplary radiation detector, as illustrated in <FIG>, the protective film <NUM> is provided between the TFT substrate <NUM> and the reinforcement member <NUM>, similarly to in the exemplary radiation detector described above.

Similarly to the reinforcement substrate <NUM>, the reinforcement member <NUM> has a higher rigidity than the base member <NUM>, such that dimensional change (deformation) with respect to force applied in a direction perpendicular to the first surface 12A is smaller than the dimensional change with respect to force applied in a direction perpendicular to the first surface 12B of the base member <NUM>. The thickness of the reinforcement member <NUM> of the present exemplary radiation detector is thicker than the thickness of the base member <NUM>, and thinner than the thickness of the reinforcement substrate <NUM>. The material employed for the reinforcement member <NUM> of the present exemplary radiation detector is preferably a thermoplastic resin, and similar materials to those of the reinforcement substrate <NUM> may be employed. Note that the rigidity referred to here refers to the difficulty of bending the reinforcement member <NUM> and the base member <NUM>, including the thicknesses of the reinforcement member <NUM> and the base member <NUM>, with bending becoming more difficult the greater the rigidity.

In the radiation detector <NUM> of the present exemplary radiation detector, a similar manufacturing method to the manufacturing method of the radiation detector <NUM> described above in the first exemplary radiation detector may, for example, be employed to affix the reinforcement substrate <NUM> provided with the spacer <NUM> to the TFT substrate <NUM> provided with the stacked body <NUM>, and then separate the TFT substrate <NUM> from the support body <NUM>. The radiation detector <NUM> of the present exemplary radiation detector can then be manufactured by performing coating or the like to provide the protective film <NUM> and the reinforcement member <NUM> on the second surface 12B of the TFT substrate <NUM>.

In the radiation detector <NUM> of the present exemplary radiation detector, the reinforcement member <NUM> that has a higher rigidity than the base member <NUM> is provided on the second surface 12B of the TFT substrate <NUM> that opposes the first surface 12A formed with the plural pixels <NUM>. This enables the TFT substrate <NUM> to be further suppressed from bending greatly, thus enabling the conversion layer <NUM> to be suppressed from detaching from the TFT substrate <NUM>, compared to the radiation detector <NUM> of the exemplary radiation detector described above.

Moreover, for example, the TFT substrate <NUM> is susceptible to warping in cases in which the difference between the coefficient of thermal expansion of the conversion layer <NUM> and the coefficient of thermal expansion of the reinforcement substrate <NUM> is comparatively large. To address this, in the radiation detector <NUM> of the present exemplary radiation detector, the TFT substrate <NUM> is sandwiched between the reinforcement substrate <NUM> and the reinforcement member <NUM>, enabling warping of the TFT substrate <NUM> due to the difference in coefficients of thermal expansion and the like to be suppressed.

As described above, each of the radiation detectors <NUM> of the exemplary radiation detectors described above includes the TFT substrate <NUM> in which the plural pixels <NUM> configured to accumulate charges generated in response to light converted from radiation are formed on the pixel region <NUM> of the flexible base member <NUM>, the conversion layer <NUM> provided on the first surface 12A, this being the surface provided with the pixel region <NUM> of the flexible base member <NUM>, and configured to convert radiation into light, and the reinforcement substrate <NUM> provided on the first surface 19A, this being the opposite-side surface of the conversion layer <NUM> to the surface on the TFT substrate <NUM> side, and that contains a material having a yield point and that has a higher rigidity than the base member <NUM>.

In the radiation detectors <NUM> of the exemplary radiation detectors described above, providing the reinforcement substrate <NUM> that contains a material having a yield point and that has a higher rigidity than the base member <NUM> on top of the conversion layer <NUM> enables sharp bending of the TFT substrate <NUM> to be suppressed. Accordingly, the radiation detectors <NUM> of the exemplary radiation detectors described above are each capable of suppressing the conversion layer <NUM> from detaching from the TFT substrate <NUM> when the radiation detector <NUM> is handled on its own.

Note that the size of the reinforcement substrate <NUM> is not limited to that of the exemplary radiation detectors described above. For example, as in the example illustrated in <FIG>, end portions (outer peripheries) of the reinforcement substrate <NUM> and the adhesion layer <NUM> may be provided at similar positions to an outer end portion (outer periphery) of the protective layer <NUM>. Note that a wider region than the region where the conversion layer <NUM> covers the first surface 12A of the TFT substrate <NUM> is preferably covered by the reinforcement substrate <NUM>, and a wider region than the region covering the entire upper face of the conversion layer <NUM> is more preferably covered by the reinforcement substrate <NUM>.

As in the example illustrated in <FIG>, a layer <NUM> configured of an inorganic material is preferably provided between the base member <NUM> and the pixels <NUM>, and in particular between the base member <NUM> and gate electrodes <NUM> of the TFTs <NUM> of the pixels <NUM>. Examples of the inorganic material employed in the example illustrated in <FIG> include SiNx, SiOx, and the like. Drain electrodes <NUM> and source electrodes <NUM> of the TFTs <NUM> are formed in the same layer as each other, and the gate electrodes <NUM> are formed between the base member <NUM> and the layer formed with the drain electrodes <NUM> and the source electrodes. The layer <NUM> that is configured of an inorganic material is provided between the base member <NUM> and the gate electrodes <NUM>.

In the exemplary radiation detectors described above, explanation has been given regarding radiation detectors in which the pixels <NUM> are arrayed in a two-dimensional matrix pattern as illustrated in <FIG>. However, there is no limitation thereto, and, for example, the pixels <NUM> may be arrayed in one dimension, or may be arrayed in a honeycomb formation. The shape of the pixels is not limited, and the pixels may be rectangular or polygonal, for example hexagonal, in shape. Obviously the shape of the pixel array <NUM> (pixel region <NUM>) is likewise not limited.

The shape and the like of the conversion layer <NUM> are also not limited to that of the exemplary radiation detectors described above. In the exemplary radiation detectors described above, explanation has been given regarding radiation detectors in which the shape of the conversion layer <NUM> is a rectangular shape similar to the shape of the pixel array <NUM> (pixel region <NUM>). However, the shape of the conversion layer <NUM> does not have to be a similar shape to that of the pixel array <NUM> (pixel region <NUM>). Moreover, instead of being rectangular, the shape of the pixel array <NUM> (pixel region <NUM>) may for example be another polygonal shape, or may be circular.

Note that although explanation has been given regarding a manufacturing method of the radiation detector <NUM> in which the separation process is performed by mechanically separating the TFT substrate <NUM> from the support body <NUM>, the separation method is not limited thereto. For example, the TFT substrate <NUM> may be separated by what is referred to as laser separation, in which a laser is irradiated onto an opposite-side surface of the support body <NUM> to the side formed with the TFT substrate <NUM>. In such cases, the radiation detector <NUM> is still capable of suppressing the conversion layer <NUM> from detaching from the TFT substrate <NUM> when the radiation detector <NUM> is handled on its own after the TFT substrate <NUM> has been separated from the support body <NUM>.

Note that in the radiation detectors <NUM> described above, either an irradiation side sampling (ISS) approach, in which radiation is irradiated from the TFT substrate <NUM> side, may be adopted, or a penetration side sampling (PSS) approach, in which radiation is irradiated from the conversion layer <NUM> side, may be adopted for the radiographic imaging device.

<FIG> is a cross-section illustrating an example of a state in which a radiographic imaging device <NUM> employing an ISS approach is applied with the radiation detector <NUM> of the first exemplary embodiment.

As illustrated in <FIG>, the radiation detector <NUM>, a power source section <NUM>, and a control board <NUM> are arranged inside a case <NUM> along a direction intersecting a direction in which radiation is incident. In the radiation detector <NUM>, the side of the pixel array <NUM> not provided with the conversion layer <NUM> opposes an imaging face 120A side of the case <NUM> that is irradiated with radiation that has passed through the imaging subject.

The case <NUM> is preferably lightweight, has a low absorption ratio of radiation R, in particular X-rays, and high rigidity, and is preferably configured from a material that has a sufficiently high elastic modulus. A material having a bending elastic modulus of at least <NUM>,<NUM> MPa is preferably employed as the material of the case <NUM>. Examples of materials suitably employed as the material of the case <NUM> include carbon or carbon fiber reinforced plastic (CFRP) having a bending elastic modulus of around <NUM>,<NUM> MPa to <NUM>,<NUM> MPa.

During capture of radiographic images by the radiographic imaging device <NUM>, a load is applied to the imaging face 120A of the case <NUM> from the imaging subject. If the rigidity of the case <NUM> were insufficient, the load from the imaging subject would cause the TFT substrate <NUM> to bend, and there would be a concern of faults occurring such as damage to the pixels <NUM>. Housing the radiation detector <NUM> inside the case <NUM> configured from a material having a bending elastic modulus of at least <NUM>,<NUM> MPa enables bending of the TFT substrate <NUM> due to the load from the imaging subject to be suppressed.

The control board <NUM> is a substrate formed with image memory <NUM> configured to store image data corresponding to the charges read from the pixels <NUM> of the pixel array <NUM>, a control section <NUM> configured to control reading of the charges from the pixels <NUM>, and the like. The control board <NUM> is electrically connected to the pixels <NUM> of the pixel array <NUM> through the flexible cables <NUM> including the plural signal lines. Note that in the radiographic imaging device <NUM> illustrated in <FIG>, the drive section <NUM> that controls the switching states of the TFTs <NUM> of the pixels <NUM> under the control of the control section <NUM>, and the signal processing section <NUM> that generates and outputs image data corresponding to the charges read from the pixels <NUM> are configured by chip-on-film (COF) provided on the flexible cables <NUM>. However, at least one out of the drive section <NUM> or the signal processing section <NUM> may be formed on the control board <NUM>.

A power source line <NUM> connects the control board <NUM> to the power source section <NUM> so as to supply electrical power to the image memory <NUM>, the control section <NUM>, and the like formed on the control board <NUM>.

A sheet <NUM> is provided inside the case <NUM> of the radiographic imaging device <NUM> illustrated in <FIG> on the side where radiation that has passed through the radiation detector <NUM> is emitted. The sheet <NUM> may, for example, be a copper sheet. A copper sheet does not readily generate secondary radiation from incident radiation, and thus has a function of preventing scattering toward the rear, namely toward the conversion layer <NUM> side. Note that the sheet <NUM> at least covers the entire surface on the radiation emission side of the conversion layer <NUM> and preferably covers the entire conversion layer <NUM>.

A protective layer <NUM> is further provided inside the case <NUM> of the radiographic imaging device <NUM> illustrated in <FIG> on the side to which radiation is incident (the imaging face 120A side). The protective layer <NUM> may, for example, be configured by a moisture-proof film such as an ALPET (registered trademark) sheet in which an aluminum layer such as an aluminum foil is bonded to an insulating sheet (film), or an insulating sheet such as a Parylene (registered trademark) film or polyethylene terephthalate. The protective layer <NUM> has a moisture-proof function and an anti-static function with respect to the pixel array <NUM>. Accordingly, the protective layer <NUM> preferably covers at least the entire surface of the pixel array <NUM> on the side to which the radiation is incident, and preferably covers the entire surface of the TFT substrate <NUM> on the side to which the radiation is incident.

Note that <FIG> illustrates an embodiment in which both the power source section <NUM> and the control board <NUM> are provided on one side of the radiation detector <NUM>, specifically on the side of one edge of the rectangular pixel array <NUM>. However, the positions at which the power source section <NUM> and the control board <NUM> are provided are not limited to those of the embodiment illustrated in <FIG>. For example, the power source section <NUM> and the control board <NUM> may be provided distributed between two opposing edges of the pixel array <NUM>, or may be provided distributed between two adjacent edges of the pixel array <NUM>.

<FIG> is a cross-section illustrating another example of a state in which the radiation detector <NUM> of the first exemplary radiation detector is applied to a radiographic imaging device <NUM> employing an ISS approach.

As illustrated in <FIG>, the power source section <NUM> and the control board <NUM> are provided arranged inside the case <NUM> in a direction intersecting the direction in which radiation is incident, and the radiation detector <NUM> and the power source section <NUM> and control board <NUM> are provided arranged inside the case <NUM> along the direction in which radiation is incident.

In the radiographic imaging device <NUM> illustrated in <FIG>, a base <NUM> is provided between the control board <NUM> and power source section <NUM> and the sheet <NUM> to support the radiation detector <NUM> and the control board <NUM>. For example, carbon or the like is employed for the base <NUM>.

The configurations and manufacturing methods of the radiation detector <NUM> and so on of the exemplary radiation detectors described above are merely examples thereof, and obviously modifications are possible.

Other Exemplary Radiation Detectors not covered by the claimed invention.

First, explanation follows regarding other exemplary configurations of the reinforcement substrate <NUM>, with reference to <FIG>.

In cases in which the conversion layer <NUM> is formed using a vapor phase deposition method, as illustrated in <FIG>, the conversion layer <NUM> is formed with a slope with a gradually decreasing thickness on progression toward an outer edge thereof. In the following explanation, a central region of the conversion layer <NUM> where the thickness may be regarded as substantially constant if manufacturing error and measurement error are ignored is referred to as a central portion 14A. An outer peripheral region of the conversion layer <NUM> where the thickness is, for example, not more than <NUM>% of the average thickness of the central portion 14A of the conversion layer <NUM> is referred to as a peripheral edge portion 14B. Namely, the conversion layer <NUM> includes a sloping face that slopes with respect to the TFT substrate <NUM> at the peripheral edge portion 14B.

As illustrated in <FIG>, an adhesion layer <NUM>, a reflective layer <NUM>, a bonding layer <NUM>, the protective layer <NUM>, and the adhesion layer <NUM> may be provided between the conversion layer <NUM> and the reinforcement substrate <NUM>.

The adhesion layer <NUM> covers the entire front surface of the conversion layer <NUM>, including the central portion 14A and the peripheral edge portion 14B of the conversion layer <NUM>. The adhesion layer <NUM> includes a function to fix the reflective layer <NUM> onto the conversion layer <NUM>. The adhesion layer <NUM> preferably has light-transmitting properties. Examples of materials that may be employed for the adhesion layer <NUM> include acrylic-based adhesives, hot-melt-based adhesives, silicone-based bonding agents, and the like. Examples of acrylic-based adhesives include, for example, urethane acrylates, acrylic resin acrylates, epoxy acrylates, and the like. Examples of hot-melt-based adhesives include thermoplastic plastics such as copolymer resins of ethylene vinyl acetate (EVA), copolymer resins of ethylene and acrylic acid (EAA), copolymer resins of ethylene and ethyl acrylate (EEA), copolymers of ethylene/methyl methacrylate (EMMA), and the like. The thickness of the adhesion layer <NUM> is preferably from <NUM> to <NUM>. Making the thickness of the adhesion layer <NUM> no less than <NUM> enables the effect of fixing the reflective layer <NUM> onto the conversion layer <NUM> to be sufficiently exhibited. Furthermore, this also enables the risk of an air layer being formed between the conversion layer <NUM> and the reflective layer <NUM> to be suppressed. Were an air layer to be formed between the conversion layer <NUM> and the reflective layer <NUM>, then there would be concern that multiple reflection of the light emitted from the conversion layer <NUM> might occur, with the light being repeatedly reflected between the air layer and the conversion layer <NUM>, and between the air layer and the reflective layer <NUM>. Moreover, making the thickness of the adhesion layer <NUM> no greater than <NUM> enables a reduction in modulation transfer function (MTF) and detective quantum efficiency (DQE) to be suppressed.

The reflective layer <NUM> covers the entire front surface of the adhesion layer <NUM>. The reflective layer <NUM> has a function of reflecting light converted by the conversion layer <NUM>. The reflective layer <NUM> is preferably configured from an organic material. Examples of materials that may be employed for the reflective layer <NUM> include white PET, TiO<NUM>, Al<NUM>O<NUM>, foamed white PET, polyester-based high reflectivity sheets, specular reflective aluminum, and the like. The thickness of the reflective layer <NUM> is preferably from <NUM> to <NUM>.

The bonding layer <NUM> covers the entire front surface of the reflective layer <NUM>. An end portion of the bonding layer <NUM> extends as far as the front surface of the TFT substrate <NUM>. Namely, the bonding layer <NUM> is bonded to the TFT substrate <NUM> at this end portion. The bonding layer <NUM> has a function to fix the reflective layer <NUM> and the protective layer <NUM> to the conversion layer <NUM>. The same materials may be employed for the material of the bonding layer <NUM> as the materials that may be employed for the adhesion layer <NUM>. However, the bonding strength of the bonding layer <NUM> is preferably greater than the bonding strength of the adhesion layer <NUM>.

The protective layer <NUM> covers the entire front surface of the bonding layer <NUM>. Namely, the protective layer <NUM> is provided in a state covering the entirety of the conversion layer <NUM>, and an end portion of the protective layer <NUM> also covers a portion of the TFT substrate <NUM>. The protective layer <NUM> functions as a moisture-proof film to prevent the ingress of moisture into the conversion layer <NUM>. Examples of materials that may be employed as the material of the protective layer <NUM> include organic films containing an organic material such as PET, PPS, OPP, PEN, PI, and the like. Moreover, an ALPET (registered trademark) sheet may be employed as the protective layer <NUM>.

The reinforcement substrate <NUM> is provided on the front surface of the protective layer <NUM>, with the adhesion layer <NUM> interposed therebetween. The same materials may, for example, be employed for the material of the adhesion layer <NUM> as the materials that may be employed for the adhesion layer <NUM> and the adhesion layer <NUM>.

In the example illustrated in <FIG>, the reinforcement substrate <NUM> extends over regions corresponding to the central portion 14A and the peripheral edge portion 14B of the conversion layer <NUM>, with an outer peripheral portion of the reinforcement substrate <NUM> angled so as to follow the slope of the peripheral edge portion 14B of the conversion layer <NUM>. The reinforcement substrate <NUM> is bonded to the protective layer <NUM> through the adhesion layer <NUM> at both the region corresponding to the central portion 14A and the region corresponding to the peripheral edge portion 14B of the conversion layer <NUM>. In the example illustrated in <FIG>, an end portion of the reinforcement substrate <NUM> is disposed at the region corresponding to the peripheral edge portion 14B of the conversion layer <NUM>.

As illustrated in <FIG>, the reinforcement substrate <NUM> may be provided only at the region corresponding to the central portion 14A of the conversion layer <NUM>. In such cases, the reinforcement substrate <NUM> is bonded to the protective layer <NUM> through the adhesion layer <NUM> at the region corresponding to the central portion 14A of the conversion layer <NUM>.

As illustrated in <FIG>, in cases in which the reinforcement substrate <NUM> extends over the regions corresponding to both the central portion 14A and the peripheral edge portion 14B of the conversion layer <NUM>, the reinforcement substrate <NUM> may be configured without providing an angled portion to follow the slope of the outer peripheral portion of the conversion layer <NUM>. In such cases, the reinforcement substrate <NUM> is bonded to the protective layer <NUM> through the adhesion layer <NUM> at the region corresponding to the central portion 14A of the conversion layer <NUM>. A space corresponding to the slope of the peripheral edge portion 14B of the conversion layer <NUM> is formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM> at the region corresponding to the peripheral edge portion 14B of the conversion layer <NUM>.

Note that the flexible cable <NUM> is connected to terminals <NUM> provided in a connection region at the outer peripheral portion of the TFT substrate <NUM>. The TFT substrate <NUM> is connected to a control board (the control board <NUM>, see <FIG>, etc.) through the flexible cable <NUM>. There is a concern that the flexible cable <NUM> might detach from the TFT substrate <NUM> or positional misalignment might arise were bending of the TFT substrate <NUM> to occur. In such cases it is necessary to perform a task to reconnect the flexible cable <NUM> and the TFT substrate <NUM>. This task to reconnect the flexible cable <NUM> and the TFT substrate <NUM> is called re-work. As illustrated in <FIG>, by arranging the end portion of the reinforcement substrate <NUM> at the inside of the end portion of the conversion layer <NUM>, re-work can be performed more easily than in cases in which the reinforcement substrate <NUM> extends to the vicinity of the connection region.

As illustrated in <FIG>, the end portion of the reinforcement substrate <NUM> may be disposed at the outer side of the end portion of the conversion layer <NUM>, and may be provided so as to be aligned with the end portions of the bonding layer <NUM> and the protective layer <NUM> that both extend over the TFT substrate <NUM>. Note that there is no need for the position of the end portion of the reinforcement substrate <NUM> to align exactly with the position of the end portions of the bonding layer <NUM> and the protective layer <NUM>.

In the example illustrated in <FIG>, the reinforcement substrate <NUM> is bonded to the protective layer <NUM> through the adhesion layer <NUM> at the region corresponding to the central portion 14A of the conversion layer <NUM>, and a space corresponding to the slope at the peripheral edge portion 14B of the conversion layer <NUM> is formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM> at the region corresponding to the peripheral edge portion 14B of the conversion layer <NUM> and also at a region at the outer side thereof.

In the example illustrated in <FIG>, a filler <NUM> is provided in the space formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM> at the region corresponding to the peripheral edge portion 14B of the conversion layer <NUM> and also at the region at the outer side thereof. The material of the filler <NUM> is not particularly limited, and examples of materials that may be employed therefor include resins. Note that in the example illustrated in <FIG>, the adhesion layer <NUM> is provided across the entire region between the reinforcement substrate <NUM> and the filler <NUM> in order to fix the reinforcement substrate <NUM> to the filler <NUM>.

The method of forming the filler <NUM> is not particularly limited. For example, after forming the adhesion layer <NUM> and the reinforcement substrate <NUM> in sequence on top of the conversion layer <NUM> covered by the adhesion layer <NUM>, the reflective layer <NUM>, the bonding layer <NUM>, and the protective layer <NUM>, flowable filler <NUM> may be poured into the space formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM>, and the filler <NUM> then cured. Alternatively, for example, after forming the conversion layer <NUM>, the adhesion layer <NUM>, the reflective layer <NUM>, the bonding layer <NUM>, and the protective layer <NUM> in sequence on top of the TFT substrate <NUM>, the filler <NUM> may be formed, and the adhesion layer <NUM> and the reinforcement substrate <NUM> may then be formed in sequence so as to cover the conversion layer <NUM> covered by the adhesion layer <NUM>, the reflective layer <NUM>, the bonding layer <NUM>, and the protective layer <NUM>, and also cover the filler <NUM>.

By filling the filler <NUM> into the space formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM> in this manner, the reinforcement substrate <NUM> can be better suppressed from detaching from the conversion layer <NUM> (the protective layer <NUM>) than in the example illustrated in <FIG>. Furthermore, due to adopting a structure in which the conversion layer <NUM> is fixed to the TFT substrate <NUM> by both the reinforcement substrate <NUM> and the filler <NUM>, the conversion layer <NUM> can be suppressed from detaching from the TFT substrate <NUM>.

In the example illustrated in <FIG>, the outer peripheral portion of the reinforcement substrate <NUM> is angled so as to follow the slope of the peripheral edge portion 14B of the conversion layer <NUM>, and so as also to cover the portions of the bonding layer <NUM> and the protective layer <NUM> that cover over the TFT substrate <NUM>. Moreover, the end portion of the reinforcement substrate <NUM> and the end portions of the bonding layer <NUM> and the protective layer <NUM> are aligned with each other. Note that there is no need for the position of the end portion of the reinforcement substrate <NUM> to align exactly with the position of the end portions of the bonding layer <NUM> and the protective layer <NUM>.

The end portions of the reinforcement substrate <NUM>, the adhesion layer <NUM>, the protective layer <NUM>, and the bonding layer <NUM> are sealed with a sealing member <NUM>. The sealing member <NUM> is preferably provided in a region spanning from the front surface of the TFT substrate <NUM> to the front surface of the reinforcement substrate <NUM>, and in a region not covering the pixel region <NUM>. Resins may be employed as the material of the sealing member <NUM>, and thermoplastic resins are particularly preferably employed therefor. Specifically, glues such as acrylic glues, urethane based glues, and the like may be employed as the sealing member <NUM>. The reinforcement substrate <NUM> has a higher rigidity than that of the protective layer <NUM>, and there is a concern that restoring force due to the angle attempting to straighten out at the angled portion of the reinforcement substrate <NUM> might act to cause the protective layer <NUM> to detach therefrom. Sealing the end portions of the reinforcement substrate <NUM>, the adhesion layer <NUM>, the protective layer <NUM>, and the bonding layer <NUM> using the sealing member <NUM> enables such detachment of the protective layer <NUM> to be suppressed.

Similarly to in the example illustrated in <FIG>, in the example illustrated in <FIG>, the filler <NUM> is provided in a space formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM> at the region corresponding to the peripheral edge portion 14B of the conversion layer <NUM> and also at the region at the outer side thereof. Moreover, at the region corresponding to the end portion of the conversion layer <NUM>, an additional and separate reinforcement substrate 40A is stacked on the front surface of the reinforcement substrate <NUM> with an adhesion layer 48A interposed therebetween. More specifically, the reinforcement substrate 40A is provided at a region straddling the end portion (outer edge, edge) of the conversion layer <NUM>. The reinforcement substrate 40A may be configured from the same materials as the reinforcement substrate <NUM>. In the radiation detector <NUM>, the amount of bending of the TFT substrate <NUM> is comparatively large at the end portion of the conversion layer <NUM>. Forming a multi-layer structure using the reinforcement substrates <NUM> and 50A at the region corresponding to the end portion of the conversion layer <NUM> enables the effect of suppressing bending of the TFT substrate <NUM> at the end portion of the conversion layer <NUM> to be enhanced.

As illustrated in <FIG>, in cases in which the end portion of the reinforcement substrate <NUM> is disposed further to the outer side than the end portion of the conversion layer <NUM> and is provided so as to be aligned with the end portions of the bonding layer <NUM> and the protective layer <NUM>, re-work can also be performed more easily than in cases in which the reinforcement substrate <NUM> extends as far as the vicinity of the connection region.

As illustrated in <FIG>, a configuration may be adopted in which the end portion of the reinforcement substrate <NUM> is provided so as to be positioned further toward the outer side than the end portions of the bonding layer <NUM> and the protective layer <NUM> that extend as far as on top of the TFT substrate <NUM>, and in a state positioned at the inner side of the end portion of the TFT substrate <NUM>.

In the example illustrated in <FIG>, the reinforcement substrate <NUM> is bonded to the protective layer <NUM> through the adhesion layer <NUM> at the region corresponding to the central portion 14A of the conversion layer <NUM>. At the region corresponding to the peripheral edge portion 14B of the conversion layer <NUM> and also at the region at the outer side thereof, a space corresponding to the slope of the peripheral edge portion 14B of the conversion layer <NUM> is formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM>, and between the TFT substrate <NUM> and the reinforcement substrate <NUM>.

In the example illustrated in <FIG>, the end portion of the reinforcement substrate <NUM> is supported by the spacer <NUM>. Namely, one end of the spacer <NUM> is connected to the first surface 12A of the TFT substrate <NUM>, and the other end of the spacer <NUM> is connected to the end portion of the reinforcement substrate <NUM> through a bonding layer <NUM>. By using the spacer <NUM> to support the end portion of the reinforcement substrate <NUM> that extends so as to form a space between itself and the TFT substrate <NUM>, detachment of the reinforcement substrate <NUM> can be suppressed. Moreover, the bending suppression effect from the reinforcement substrate <NUM> can be caused to act as far as the vicinity of the end portion of the TFT substrate <NUM>. Note that instead of providing the spacer <NUM>, or in addition to providing the spacer <NUM>, a filler may be filled into the space formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM>, and between the TFT substrate <NUM> and the reinforcement substrate <NUM>, in a similar manner to the example illustrated in <FIG>.

In the example illustrated in <FIG>, the outer peripheral portion of the reinforcement substrate <NUM> is angled so as to follow the slope at the peripheral edge portion 14B of the conversion layer <NUM>, and covers the portion where the bonding layer <NUM> and the protective layer <NUM> cover over the TFT substrate <NUM> and also covers over the TFT substrate <NUM> at the outer side thereof. Namely, the end portions of the bonding layer <NUM> and the protective layer <NUM> are sealed by the reinforcement substrate <NUM>. The portion of the reinforcement substrate <NUM> that extends over the TFT substrate <NUM> is bonded to the TFT substrate <NUM> through the adhesion layer <NUM>. By covering the end portions of the bonding layer <NUM> and the protective layer <NUM> using the reinforcement substrate <NUM> in this manner, detachment of the protective layer <NUM> can be suppressed. Note that the sealing member <NUM> may be employed to seal the end portion of the reinforcement substrate <NUM>, in a similar manner to the example illustrated in <FIG>.

The example illustrated in <FIG> is an example in which the end portion of the reinforcement substrate <NUM> is supported by the spacer <NUM>, and an additional and separate reinforcement substrate 40A is stacked on the front surface of the reinforcement substrate <NUM> at the region corresponding to the end portion of the conversion layer <NUM>, with the adhesion layer 48A interposed therebetween. More specifically, the reinforcement substrate 40A is provided at a region straddling the end portion (outer edge, edge) of the conversion layer <NUM>. The reinforcement substrate 40A may be configured from the same materials as the reinforcement substrate <NUM>. In the radiation detector <NUM>, the amount of bending of the TFT substrate <NUM> is comparatively large at the end portion of the conversion layer <NUM>. Forming a multi-layer structure using the reinforcement substrates <NUM> and 40A at the region corresponding to the end portion of the conversion layer <NUM> enables the effect of suppressing bending of the TFT substrate <NUM> at the end portion of the conversion layer <NUM> to be enhanced. Note that instead of providing the spacer <NUM>, the filler <NUM> may be filled into the space formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM>, and between the TFT substrate <NUM> and the reinforcement substrate <NUM>, in a similar manner to the example illustrated in <FIG>.

As illustrated in <FIG>, the end portion of the reinforcement substrate <NUM> may be provided so as to be aligned with the end portion of the TFT substrate <NUM>. Note that there is no need for the position of the end portion of the reinforcement substrate <NUM> to align exactly with the position of the end portion of the TFT substrate <NUM>.

In the example illustrated in <FIG>, the reinforcement substrate <NUM> is bonded to the protective layer <NUM> through the adhesion layer <NUM> at the region corresponding to the central portion 14A of the conversion layer <NUM>. A space corresponding to the slope of the peripheral edge portion 14B of the conversion layer <NUM> is formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM>, and between the TFT substrate <NUM> and the reinforcement substrate <NUM>, at the region corresponding to the peripheral edge portion 14B of the conversion layer <NUM> and also at the region at the outer side thereof.

In the example illustrated in <FIG>, the end portion of the reinforcement substrate <NUM> is supported by the spacer <NUM>. Namely, one end of the spacer <NUM> is connected to the flexible cable <NUM> provided at the end portion of the TFT substrate <NUM>, and the other end of the spacer <NUM> is connected to the end portion of the reinforcement substrate <NUM> through the bonding layer <NUM>. By using the spacer <NUM> to support the end portion of the reinforcement substrate <NUM> that extends so as to form a space between itself and the TFT substrate <NUM>, detachment of the reinforcement substrate <NUM> can be suppressed. Moreover, the bending suppression effect from the reinforcement substrate <NUM> can be caused to act as far as the vicinity of the end portion of the TFT substrate <NUM>.

In the example illustrated in <FIG>, the space formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM>, and between the TFT substrate <NUM> and the reinforcement substrate <NUM>, is filled by the filler 70The connection portions between the flexible cable <NUM> and the terminals <NUM> are covered by the filler <NUM>. By thus filling the space formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM>, and between the TFT substrate <NUM> and the reinforcement substrate <NUM>, with the filler <NUM>, the reinforcement substrate <NUM> can be better suppressed from detaching from the conversion layer <NUM> (the protective layer <NUM>) than in the embodiment illustrated in <FIG>. Furthermore, due to the structure in which the conversion layer <NUM> is fixed to the TFT substrate <NUM> by both the reinforcement substrate <NUM> and the filler <NUM>, the conversion layer <NUM> can be suppressed from detaching from the TFT substrate <NUM>. Moreover, since the connection portions between the flexible cable <NUM> and the terminals <NUM> are covered by the filler <NUM>, detachment of the flexible cable <NUM> can also be suppressed.

In the example illustrated in <FIG>, the outer peripheral portion of the reinforcement substrate <NUM> is angled so as to follow the slope of the peripheral edge portion 14B of the conversion layer <NUM>, and covers a portion where the bonding layer <NUM> and the protective layer <NUM> cover over the TFT substrate <NUM>, a portion on top of the substrate at the outer side thereof, and the connection portions between the flexible cable <NUM> and the terminals <NUM>. The portions of the reinforcement substrate <NUM> extending over the TFT substrate <NUM> and over the flexible cable <NUM> are respectively bonded to the TFT substrate <NUM> and the flexible cable <NUM> through the adhesion layer <NUM>. The connection portions between the flexible cable <NUM> and the terminals <NUM> are covered by the bent reinforcement substrate <NUM>, enabling detachment of the flexible cable <NUM> to be suppressed. Moreover, since the other end of the flexible cable <NUM> is anticipated to be connected to a control board mounted with electronic components, there is a concern regarding comparatively large bending of the TFT substrate <NUM> occurring at the connection portions between the flexible cable <NUM> and the terminals <NUM>. Since the connection portions between the flexible cable <NUM> and the terminals <NUM> are covered by the reinforcement substrate <NUM>, such bending of the TFT substrate <NUM> at these portions can be suppressed.

In the example illustrated in <FIG>, a space formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM>, and between the TFT substrate <NUM> and the reinforcement substrate <NUM>, is filled with the filler <NUM>. Moreover, an additional and separate bending reinforcement substrate 40A is stacked on the front surface of the reinforcement substrate <NUM> at the region corresponding to the end portion of the conversion layer <NUM>, with the adhesion layer 48A interposed therebetween. More specifically, the reinforcement substrate 40A is provided at a region straddling the end portion (outer edge, edge) of the conversion layer <NUM>. The reinforcement substrate 40A may be configured from the same materials as the reinforcement substrate <NUM>. In the radiation detector <NUM>, the amount of bending of the TFT substrate <NUM> is comparatively large at the end portion of the conversion layer <NUM>. Forming a multi-layer structure using the reinforcement substrates <NUM> and 40A at the region corresponding to the end portion of the conversion layer <NUM> enables the effect of suppressing bending of the TFT substrate <NUM> to be enhanced at the end portion of the conversion layer <NUM>.

As illustrated in <FIG>, the end portion of the reinforcement substrate <NUM> may be provided so as to be positioned at the outer side of the end portion of the TFT substrate <NUM>.

In the example illustrated in <FIG>, the end portion of the reinforcement substrate <NUM> is supported by the spacer <NUM>. Namely, one end of the spacer <NUM> is connected to the flexible cable <NUM> provided at the end portion of the TFT substrate <NUM>, and the other end of the spacer <NUM> is connected to the end portion of the reinforcement substrate <NUM> through the bonding layer <NUM>. By using the spacer <NUM> to support the end portion of the reinforcement substrate <NUM> that extends so as to form the space between itself and the TFT substrate <NUM>, detachment of the reinforcement substrate <NUM> can be suppressed. Moreover, the bending suppression effect from the reinforcement substrate <NUM> can be caused to act as far as the vicinity of the end portion of the TFT substrate <NUM>.

In the example illustrated in <FIG>, the filler <NUM> is filled into the space formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM>, and between the TFT substrate <NUM> and the reinforcement substrate <NUM>. The connection portions between the flexible cable <NUM> and the terminals <NUM> are covered by the filler <NUM>. By filling the filler <NUM> into the space formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM> and between the TFT substrate <NUM> and the reinforcement substrate <NUM> in this manner, the reinforcement substrate <NUM> can be better suppressed from detaching from the conversion layer <NUM> (the protective layer <NUM>) than in the example illustrated in <FIG>. Furthermore, due to the structure in which the conversion layer <NUM> is fixed to the TFT substrate <NUM> by both the reinforcement substrate <NUM> and the filler <NUM>, the conversion layer <NUM> can be suppressed from detaching from the TFT substrate <NUM>. Moreover, since the connection portions between the flexible cable <NUM> and the terminals <NUM> are covered by the filler <NUM>, detachment of the flexible cable <NUM> can be suppressed.

In the example illustrated in <FIG>, the outer peripheral portion of the reinforcement substrate <NUM> is angled so as to follow the slope of the peripheral edge portion 14B of the conversion layer <NUM>. The outer peripheral portion of the reinforcement substrate <NUM> also covers the portion where the bonding layer <NUM> and the protective layer <NUM> cover over the TFT substrate <NUM>, the portion on top of the substrate at the outer side thereof, and the connection portions between the flexible cable <NUM> and the terminals <NUM>. The portions of the reinforcement substrate <NUM> extending over the TFT substrate <NUM> and over the flexible cable <NUM> are respectively bonded to the TFT substrate <NUM> and the flexible cable <NUM> through the adhesion layer <NUM>. By covering the connection portions between the flexible cable <NUM> and the terminals <NUM> with the reinforcement substrate <NUM>, detachment of the flexible cable <NUM> can be suppressed. Moreover, since the other end of the flexible cable <NUM> is anticipated to be connected to a control board mounted with electronic components, there is a concern regarding comparatively large bending of the TFT substrate <NUM> at the connection portions between the flexible cable <NUM> and the terminals <NUM>. Since the connection portions between the flexible cable <NUM> and the terminals <NUM> are covered by the reinforcement substrate <NUM>, such bending of the TFT substrate <NUM> at these portions can be suppressed.

In the example illustrated in <FIG>, the filler <NUM> is filled into the space formed between the conversion layer <NUM> (the protective layer <NUM>) and the reinforcement substrate <NUM> and between the TFT substrate <NUM> and the reinforcement substrate <NUM>. Moreover, the additional and separate reinforcement substrate 40A is stacked on the front surface of the reinforcement substrate <NUM> at the region corresponding to the end portion of the conversion layer <NUM>, with the adhesion layer 48A interposed therebetween. More specifically, the reinforcement substrate 40A is provided at a region straddling the end portion (outer edge, edge) of the conversion layer <NUM>. The reinforcement substrate 40A may be configured from the same materials as the reinforcement substrate <NUM>. In the radiation detector <NUM>, the amount of bending of the TFT substrate <NUM> is comparatively large at the end portion of the conversion layer <NUM>. Forming a multi-layer structure using the reinforcement substrates <NUM> and 40A at the region corresponding to the end portion of the conversion layer <NUM> enables the effect of suppressing bending of the TFT substrate <NUM> to be enhanced at the end portion of the conversion layer <NUM>.

As described previously, in processes to manufacture the radiation detector <NUM>, the flexible TFT substrate <NUM> is affixed onto the support body <NUM>, for example a glass substrate. After stacking the conversion layer <NUM> on top of the TFT substrate <NUM>, the support body <NUM> is separated from the TFT substrate <NUM>. Bending occurs in the flexible TFT substrate <NUM> when this is performed, and so there is a concern that the pixels <NUM> formed on top of the TFT substrate <NUM> might be damaged thereby. By stacking the reinforcement substrate <NUM> on top of the conversion layer <NUM> as in the examples illustrated in the examples of <FIG> prior to separating the support body <NUM> from the TFT substrate <NUM>, the bending of the TFT substrate <NUM> that occurs when the support body <NUM> is being separated from the TFT substrate <NUM> can be suppressed, enabling the risk of damage to the pixels <NUM> to be reduced.

Moreover, the reinforcement substrate <NUM> is not limited to a single layer (one layer), and may be configured with multiple layers. For example, in the radiation detector <NUM> in the example illustrated in <FIG>, the reinforcement substrate <NUM> is a multi-layered film configured of three layers in which a first reinforcement substrate 40B, a second reinforcement substrate 40C, and a third reinforcement substrate 40D are stacked in sequence from the side closest to the conversion layer <NUM>.

In cases in which the reinforcement substrate <NUM> has multiple layers, each of the layers included in the reinforcement substrate <NUM> preferably has a different function. For example, in the example illustrated in <FIG>, the first reinforcement substrate 40B and the third reinforcement substrate 40D may be configured as layers having a non-conductive anti-static function, while the second reinforcement substrate 40C may be configured as a conductive layer such that the reinforcement substrate <NUM> has an electromagnetic shielding function. In such cases, the first reinforcement substrate 40B and the third reinforcement substrate 40D may employ an anti-static film such as a film employing the anti-static coating COLCOAT (trade name, manufactured by COLCOAT Co. The second reinforcement substrate 40C may employ a conductive sheet, or a conductive mesh sheet made of Cu or the like.

For example, in cases in which the reading approach of the radiation detector <NUM> is an ISS approach, the control board <NUM>, the power source section <NUM>, and the like may be provided on the conversion layer <NUM> side (see <FIG>). Providing the reinforcement substrate <NUM> with an anti-static function in this manner enables electromagnetic noise from the control board <NUM> and the power source section <NUM> to be shielded.

<FIG> is a plan view illustrating an example of a structure of the reinforcement substrate <NUM>. A main face of the reinforcement substrate <NUM> may include plural through holes <NUM>. The size and pitch of the through holes <NUM> is prescribed so as to obtain the desired rigidity of the reinforcement substrate <NUM>.

Including the plural through holes <NUM> in the reinforcement substrate <NUM> enables air introduced at the joining face of the reinforcement substrate <NUM> to the conversion layer <NUM> to escape through the through holes <NUM>. This enables air bubbles to be suppressed from being generated at the joining face of the reinforcement substrate <NUM> to the conversion layer <NUM>.

There is a concern that air bubbles might be generated at the joining face if no mechanism is provided to allow air introduced at the joining face of the reinforcement substrate <NUM> to the conversion layer <NUM> to escape. For example, were air bubbles generated at the joining face to expand due to heat during operation of the radiographic imaging device <NUM>, there would be a drop in the cohesion between the reinforcement substrate <NUM> and the conversion layer <NUM>. This would lead to a concern that the bending suppression effect from the reinforcement substrate <NUM> might not be sufficiently exhibited. By using the reinforcement substrate <NUM> including the plural through holes <NUM> as illustrated in <FIG>, the generation of air bubbles at the joining face of the reinforcement substrate <NUM> to the conversion layer <NUM> can be suppressed as described above, enabling the cohesion between the reinforcement substrate <NUM> and the conversion layer <NUM> to be maintained. This enables the bending suppression effect of the reinforcement substrate <NUM> to be maintained.

<FIG> is a perspective view illustrating another example of the structure of the reinforcement substrate <NUM>. In the example illustrated in <FIG>, the reinforcement substrate <NUM> includes an indented-and-protruding structure on the joining face to the conversion layer <NUM>. The indented-and-protruding structure may be configured including plural grooves <NUM> arranged parallel to each other, as illustrated in <FIG>. The face of the reinforcement substrate <NUM> that includes the indented-and-protruding structure configured from the plural grooves <NUM> is, for example as illustrated in <FIG>, joined to the conversion layer <NUM> that has been covered by the reflective layer <NUM>. Due to the reinforcement substrate <NUM> including the indented-and-protruding structure on the joining face to the conversion layer <NUM> in this manner, any air introduced to the joining portion of the reinforcement substrate <NUM> and the conversion layer <NUM> is able to escape through the grooves <NUM>. Similarly to in the example illustrated in <FIG>, this accordingly enables the generation of air bubbles at the joining face of the reinforcement substrate <NUM> to the conversion layer <NUM> to be suppressed. This enables the cohesion between the reinforcement substrate <NUM> and the conversion layer <NUM> to be maintained, and enables the bending suppression effect of the reinforcement substrate <NUM> to be maintained.

<FIG> and <FIG> are plan views illustrating other examples of structures of the reinforcement substrate <NUM>. As illustrated in <FIG> and <FIG>, the reinforcement substrate <NUM> may be segmented into plural pieces <NUM>. The reinforcement substrate <NUM> may, as illustrated in <FIG>, be segmented into the plural pieces <NUM> (<FIG><NUM> to <NUM><NUM>) arrayed along one direction. Alternatively, the reinforcement substrate <NUM> may, as illustrated in <FIG>, be segmented into the plural pieces <NUM> (<FIG><NUM> to <NUM><NUM>) arrayed in both a longitudinal direction and a lateral direction.

The greater the surface area of the reinforcement substrate <NUM>, the more readily air bubbles are generated at the joining face of the reinforcement substrate <NUM> to the conversion layer <NUM>. As illustrated in <FIG> and <FIG>, segmenting the reinforcement substrate <NUM> into the plural pieces <NUM> enables the generation of air bubbles at the j oining face of the reinforcement substrate <NUM> to the conversion layer <NUM> to be suppressed. This enables the cohesion between the reinforcement substrate <NUM> and the conversion layer <NUM> to be maintained, and thereby enables the bending suppression effect of the reinforcement substrate <NUM> to be maintained.

A reinforcement member <NUM> may be provided on the opposite side of the reinforcement member <NUM> to the side contacting the TFT substrate <NUM> (the second surface 12B). <FIG> are cross-sections respectively illustrating examples of installation of the reinforcement member <NUM>.

In the examples illustrated in <FIG>, the reinforcement member <NUM> is stacked on an opposite-side surface of the reinforcement member <NUM> to the surface on the TFT substrate <NUM> side, with a bonding layer <NUM> interposed therebetween. The reinforcement member <NUM> may be configured from the same materials as the reinforcement substrate <NUM>. In cases in which the radiation detector <NUM> employs an ISS approach, the reinforcement member <NUM> is preferably provided only at an outer peripheral portion of the TFT substrate <NUM> so as to keep the surface area of locations where the reinforcement member <NUM> and the pixel region <NUM> overlap each other as small as possible. Namely, the reinforcement member <NUM> may have a ring shape with an opening <NUM> at a location corresponding to the pixel region <NUM>, as illustrated in <FIG>. Forming a multi-layer structure with the reinforcement member <NUM> and the reinforcement member <NUM> at the outer peripheral portion of the TFT substrate <NUM> in this manner enables the rigidity of the outer peripheral portion of the TFT substrate <NUM> that is comparatively susceptible to bending to be reinforced.

In the examples illustrated in <FIG>, the reinforcement member <NUM> is provided at a region straddling the end portion (outer edge, edge) of the conversion layer <NUM>. In the radiation detector <NUM>, the amount of bending of the TFT substrate <NUM> is comparatively large at the end portion of the conversion layer <NUM>. Forming a multi-layer structure using the reinforcement member <NUM> and the reinforcement member <NUM> at the region corresponding to the end portion of the conversion layer <NUM> enables the effect of suppressing bending of the TFT substrate <NUM> to be enhanced at the end portion of the conversion layer <NUM>.

In cases in which an ISS approach is employed in the radiation detector <NUM>, there is a concern that were a portion of the reinforcement member <NUM> to overlap with the pixel region <NUM> as illustrated in <FIG>, this might have an impact on the images, depending on the material employed in the reinforcement member <NUM>. Thus, in cases in which a portion of the reinforcement member <NUM> overlaps with the pixel region <NUM>, a plastic is preferably employed for the material of the reinforcement member <NUM>.

As illustrated in <FIG> and <FIG>, most preferably the reinforcement member <NUM> straddles the end portion (outer edge, edge) of the conversion layer <NUM> but does not overlap with the pixel region <NUM> (namely, an exampleiment in which an edge of the opening <NUM> in the reinforcement member <NUM> is disposed at the outer side of the pixel region <NUM>). In the example illustrated in <FIG>, the position of the edge of the opening <NUM> in the reinforcement member <NUM> is substantially aligned with the position of the end portion of the pixel region <NUM>. In the example illustrated in <FIG>, the edge of the opening <NUM> in the reinforcement member <NUM> is disposed between the end portion of the pixel region <NUM> and the end portion of the conversion layer <NUM>.

Moreover, the position of the edge of the opening <NUM> in the reinforcement member <NUM> may be disposed so as to be substantially aligned with the position of the end portion of the conversion layer <NUM> as illustrated in <FIG>, or may be disposed so as to be further toward the outer side than the end portion of the conversion layer <NUM> as illustrated in <FIG>. In such cases, there is no structure present where the reinforcement member <NUM> straddles the end portion (outer edge, edge) of the conversion layer <NUM>, and so there might be a concern regarding a lessening of the effect of suppressing bending of the TFT substrate <NUM> at the end portion of the conversion layer <NUM>. However, due to forming a stacked structure using the reinforcement member <NUM> and the reinforcement member <NUM> at the outer peripheral portion of the TFT substrate <NUM> where the connection portions between the flexible cable <NUM> and the terminals <NUM> are present, the effect of suppressing bending of the TFT substrate <NUM> at the connection portions between the flexible cable <NUM> and the terminals <NUM> is maintained.

In the radiation detectors <NUM> described above, explanation has been given regarding embodiments in which the size of the TFT substrate <NUM> (base member <NUM>) and the size of the reinforcement member <NUM> are the same as each other. However, the size of the TFT substrate <NUM> and the size of the reinforcement member <NUM> may be different to each other.

For example, in cases in which the radiation detector <NUM> is applied to the radiographic imaging device <NUM>, the radiation detector <NUM> may be employed fixed to the case <NUM> (see <FIG>, etc.) or the like that houses the radiation detector <NUM>. In such cases, as in the example illustrated in <FIG>, the reinforcement member <NUM> may be made larger than the TFT substrate <NUM> and provided with a flap or the like in order to fix the radiation detector <NUM> using the location of the flap or the like. An example may be configured in which holes are provided in a flap portion of the reinforcement member <NUM>, and screws are passed through the holes to fix the reinforcement member <NUM> to the case <NUM> (see <FIG>, etc.).

Note that examples in which the reinforcement member <NUM> is larger than the TFT substrate <NUM> are not limited to the embodiment illustrated in <FIG>. An example may be configured in which the reinforcement member <NUM> is configured with plural stacked layers, with some of these layers being larger than the TFT substrate <NUM>. For example, as illustrated in <FIG>, the reinforcement member <NUM> may be configured with a dual-layer structure including a first layer 41A of similar size to the TFT substrate <NUM> (the base member <NUM>) and a second layer 41B that is larger than the TFT substrate <NUM>. The first layer 41Ais affixed to the second layer 41B using double-sided tape, an adhesion layer, or the like (not illustrated in the drawings). For example, the first layer 41A is preferably formed of similar materials to those of the reinforcement member <NUM> described above so as to possess similar properties to the reinforcement member <NUM>. The second layer 41B is affixed to the second surface 12B of the base member <NUM> using double-sided tape, an adhesion layer, or the like (not illustrated in the drawings). For example, ALPET (registered trademark) may be applied as the second layer 41B. In cases in which the reinforcement member <NUM> is configured with plural layers, conversely to the example illustrated in <FIG>, an example may be configured in which the first layer 41A is affixed to the second surface 12B of the base member <NUM>, as illustrated in <FIG>.

As described above, in cases in which the radiation detector <NUM> is fixed to the case <NUM> (see <FIG>, etc.) or the like using a flap or the like provided to the reinforcement member <NUM>, such fixing may be performed in a state in which the flap portion is bent. The thinner the thickness thereof, the more easily the flap portion of the reinforcement member <NUM> will bend, enabling the flap portion alone to be bent without affecting the main body of the radiation detector <NUM>. Accordingly, in cases in which the flap portion or the like is to be bent, an example in which the reinforcement member <NUM> is configured of plural stacked layers with some of these layers being configured larger than the TFT substrate <NUM> as illustrated in the examples of <FIG> is preferable.

As in the example illustrated in <FIG>, conversely to the radiation detectors <NUM> in <FIG>, the reinforcement member <NUM> may be smaller than the TFT substrate <NUM>. Positioning an end portion of the TFT substrate <NUM> at the outer side of an end portion of the reinforcement member <NUM> facilitates checking of the position of the end portion of the TFT substrate <NUM> during assembly, for example when housing the radiation detector <NUM> inside the case <NUM> (see <FIG>, etc.), thus enabling positioning precision to be improved. Note that there is no limitation to the example illustrated in <FIG>, since as long as at least a portion of the end portion of the TFT substrate <NUM> (the base member <NUM>) is positioned at the outer side of the reinforcement member <NUM>, similar advantageous effects can be obtained and is therefore preferable.

Explanation follows regarding examples of the radiographic imaging device <NUM> in which the radiation detector <NUM> is housed inside the case <NUM>, with reference to <FIG> are diagrams illustrating other configuration examples of the radiographic imaging device <NUM>.

The example illustrated in <FIG> is a radiographic imaging device <NUM> employing an ISS approach, similarly to the radiographic imaging device <NUM> illustrated in <FIG>. The example illustrated in <FIG> is a radiographic imaging device <NUM> employing a PSS approach. In the examples illustrated in <FIG> and <FIG>, the radiation detector <NUM>, the control board <NUM>, and the power source section <NUM> are arranged alongside one another in the lateral direction of the respective drawings.

Note that <FIG> and <FIG> illustrate examples in which both the power source section <NUM> and the control board <NUM> are provided on one side of the radiation detector <NUM>, specifically on the side of one edge of the rectangular pixel region <NUM>. However, the positions at which the power source section <NUM> and the control board <NUM> are provided are not limited to those of the examples illustrated in <FIG> and <FIG>. For example, the power source section <NUM> and the control board <NUM> may be provided distributed between two opposing edges of the pixel region <NUM>, or may be provided distributed between two adjacent edges of the pixel region <NUM>.

As in the examples illustrated in <FIG> and <FIG>, in cases in which the radiation detector <NUM>, the control board <NUM>, and the power source section <NUM> are arranged in a direction intersecting the direction in which the TFT substrate <NUM> and the conversion layer <NUM> are stacked, the thickness of the case <NUM> may be varied between the locations of the case <NUM> where the power source section <NUM> and the control board <NUM> are respectively provided, and the location of the case <NUM> where the radiation detector <NUM> is provided.

The power source section <NUM> and the control board <NUM> are often each thicker than the radiation detector <NUM>, as in the example illustrated in <FIG>. In such cases, as in the example illustrated in <FIG>, the thickness of the location of the case <NUM> where the radiation detector <NUM> is provided may be less than the thickness of the locations of the case <NUM> where the power source section <NUM> and the control board <NUM> are provided. In cases in which the thickness is varied between the locations of the case <NUM> where the power source section <NUM> and the control board <NUM> are respectively provided and the location of the case <NUM> where the radiation detector <NUM> is provided in this manner, since there might be a concern of causing discomfort or the like to the imaging subject who touches a boundary 120B where a step is created at a boundary between these locations, the boundary 120B is preferably provided with a slope.

So doing enables an ultra-thin portable electronic cassette to be configured according to the thickness of the radiation detector <NUM>.

As another example, in such cases, the case <NUM> may be configured of different materials at the locations of the case <NUM> where the power source section <NUM> and the control board <NUM> are provided and the location of the case <NUM> where the radiation detector <NUM> is provided. Moreover, for example, the locations of the case <NUM> where the power source section <NUM> and the control board <NUM> are provided and the location of the case <NUM> where the radiation detector <NUM> is provided may be configured separately to each other.

Moreover, as described previously, the case <NUM> preferably has a low absorption ratio of the radiation R, in particular X-rays, and high rigidity, and is preferably configured from a material that has a sufficiently high elastic modulus. However, as in the example illustrated in <FIG>, a location 120C of the case <NUM> corresponding to the imaging face 120A may be configured with a low absorption ratio of the radiation R and high rigidity, and be configured from a material that has a sufficiently high elastic modulus, while other locations of the case <NUM> are configured from a different material than the location 120C, for example a material having a lower elastic modulus than the location 120C.

Alternatively, the radiation detector <NUM> and an inner wall face of the case <NUM> may contact each other as in the example illustrated in <FIG>. In such cases, the radiation detector <NUM> and the inner wall face of the case <NUM> may be bonded through a bonding layer, or may simply be in contact with each other without providing a bonding layer. Such contact between the radiation detector <NUM> and the inner wall face of the case <NUM> further secures the rigidity of the radiation detector <NUM>.

Claim 1:
A manufacturing method for a radiation detector (<NUM>), comprising:
a process of coating an adhesion layer (<NUM>) onto a reinforcement substrate (<NUM>) having a size according to the size of a radiation detector (<NUM>);
a process of forming a substrate (<NUM>) by providing a flexible base member (<NUM>) to a support body (<NUM>) with a separation layer interposed between the base member (<NUM>) and the support body (<NUM>), and providing a plurality of pixels (<NUM>) in a pixel region (<NUM>) of the base member (<NUM>), the plurality of pixels (<NUM>) accumulates charges generated in response to light converted from radiation;
a process of forming a conversion layer (<NUM>) that converts the radiation into light at a surface to which the pixel region (<NUM>) of the base member (<NUM>) is provided;
a process of affixing the reinforcement substrate (<NUM>) at a surface of the conversion layer (<NUM>) opposite to a surface that faces a surface of the substrate side using the adhesion layer (<NUM>) on the reinforcement substrate (<NUM>), the reinforcement substrate (<NUM>) containing a material having a yield point and having a higher rigidity than the base member (<NUM>); and
a process of separating the substrate (<NUM>) provided with the conversion layer (<NUM>) and the reinforcement substrate (<NUM>) from the support body (<NUM>).