RADIATION DETECTING DEVICE AND METHOD FOR MANUFACTURING RADIATION DETECTING DEVICE

In a radiation detecting device, a groove portion is provided in a sealing region on a photoelectric conversion substrate. The groove portion is provided in the vicinity of a phosphor layer formed on the photoelectric conversion substrate or along an outer peripheral side thereof. A moisture-proof protective layer is provided to cover the phosphor layer and the sealing region through an adhesive layer. The adhesive layer is cured when in a flowable state to function as an adhesive. In a case where the moisture-proof protective layer is adhered, the adhesive layer enters a flowable state, and thus, the adhesive layer flows into the groove portion and fills at least a part of the inside of the groove portion.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a radiation detecting device and a method for manufacturing the radiation detecting device.

2. Description of the Related Art

In the related art, a radiation imaging device that performs radiation imaging for medical diagnosis is known. In such a radiation imaging device, a radiation detecting device for detecting radiation passed through an object to generate a radiographic image is used.

As the radiation detecting device, there is a radiation detecting device that includes a substrate where pixels that generate electric charges according to emitted light are provided and a phosphor layer that is formed on the substrate and converts radiation into light to emit the light onto the substrate. In order to protect the phosphor layer formed on the substrate, a surface thereof is covered with a protective film or the like (see JP2013-118220A and JP2006-343277A).

SUMMARY OF THE INVENTION

When forming a phosphor layer in a partial region of a substrate, in a case where the phosphor layer is covered with a protective film or the like with an adhesive therebetween, a liquid reservoir may be generated due to the adhesive in an edge portion of the phosphor layer and the thickness of an adhesive layer may increase in a region of the edge portion. In such a case, when the thickness of the adhesive layer increases, there is a concern that moisture may easily intrude and thus durability of the radiation detecting device may deteriorate.

The invention provides a radiation detecting device and a method for manufacturing the radiation detecting device capable of preventing intrusion of moisture and enhancing durability performance of the radiation detecting device.

According to a first aspect of the invention, there is provided a radiation detecting device including: a substrate on which a plurality of pixels that receive light generated by emitted radiation and generate electric charges is arranged; a first protective layer that is provided on the substrate; a phosphor layer that is provided on the first protective layer and receives the radiation to generate the light; and a second protective layer that is formed to cover the phosphor layer with a resin therebetween, in which a groove portion that is filled with the resin is formed in the first protective layer, in a sealing region that surrounds a region where the phosphor layer is provided.

According to a second aspect of the invention, in the radiation detecting device according to the first aspect, the groove portion may surround the phosphor layer.

According to a third aspect of the invention, in the radiation detecting device according to the first aspect, the groove portion may be formed along each outer peripheral side of the phosphor layer.

According to a fourth aspect of the invention, in the radiation detecting device according to the third aspect, an edge portion of the groove portion may be formed to be aligned with the outer peripheral side.

According to a fifth aspect of the invention, in the radiation detecting device according to any one of the first to fourth aspects, the resin may be a resin that is curable according to application of stress.

According to a sixth aspect of the invention, in the radiation detecting device according to any one of the first to fifth aspects, the resin may be a hot melt resin or a photocurable resin.

According to a seventh aspect of the invention, in the radiation detecting device according to any one of the first to sixth aspects, the groove portion may be provided at a position closer to an inner periphery than to an outer periphery of the sealing region, in the sealing region.

According to an eighth aspect of the invention, in the radiation detecting device according to any one of the first to seventh aspects, the groove portion may pass through the first protective layer, and may reach the inside of the substrate.

According to a ninth aspect of the invention, there is provided a method for manufacturing a radiation detecting device, the method including: a preparation process of preparing a substrate on which a first protective layer is formed and a plurality of pixels that receives light generated by emitted radiation and generates electric charges is arranged; a groove portion formation process of forming, prior to a phosphor layer formation process of forming a phosphor layer that receives the radiation to generate the light, a groove portion in the first protective layer in a sealing region that surrounds a region where the phosphor layer is provided; a phosphor layer formation process of forming the phosphor layer on the first protective layer; and a second protective layer formation process of forming a second protective layer to cover the phosphor layer with a resin therebetween.

According to the above-described aspects of the invention, it is possible to provide a radiation detecting device and a method for manufacturing the radiation detecting device capable of preventing intrusion of moisture and enhancing durability performance of the radiation detecting device.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, embodiments of the invention will be described with reference to the accompanying drawings. The embodiments do not limit the invention.

First Embodiment

A radiation detecting device of a first embodiment has a function of receiving radiation passed though an object and outputting image information indicating a radiographic image of the object. The radiation detecting device includes a photoelectric conversion substrate and a phosphor layer which is a scintillator that receives radiation and emits light.

FIG. 1shows an example of a specific configuration of the radiation detecting device of this embodiment.

A radiation detecting device10comprises a photoelectric conversion substrate12, and the photoelectric conversion substrate12includes a thin film transistor (TFT) substrate14on which plural pixels20are formed. As shown inFIG. 1, the TFT substrate14of the photoelectric conversion substrate12includes the plural pixels20that include a sensor unit24and a switch element22. The sensor unit24receives light generated in a phosphor layer to generate electric charges. The switch element22reads the electric charges accumulated by the sensor unit24. A thin film transistor or the like may be used as a specific example of the switch element22. Hereinafter, the switch element is referred to as a “TFT”.

The plural pixels20are arranged in a matrix form in one direction (a scanning interconnect direction corresponding to a transverse direction inFIG. 1, which is hereinafter referred to as a “row direction”) and a crossing direction (a signal interconnect direction corresponding to a longitudinal direction inFIG. 1, which is hereinafter referred to as a “column direction”) with respect to the row direction. Arrangement of the pixels20is briefly shown inFIG. 1, but for example, 1024×1024 pixels20are arranged in the row direction and the column direction.

Further, in the radiation detecting device10, plural scanning interconnects28(G1to G4) for controlling on/off of the TFT22and plural signal interconnects26(D1to D4) provided for each pixel20, from which electric charges accumulated by the sensor unit24are read, alternately intersect each other.

In the sensor unit24of each pixel20, a common interconnect29is provided in a interconnect direction of the signal interconnect26in order to apply a bias voltage to each pixel20. The bias voltage is applied from a power source (not shown) through the common interconnect29.

FIG. 2shows a plan view of the radiation detecting device10shown inFIG. 1. Further,FIG. 3shows an A-A sectional view of the radiation detecting device10shown inFIG. 2. InFIG. 2, a phosphor layer82is not shown.

As shown inFIG. 3, the radiation detecting device10is configured so that the scanning interconnect28, a gate electrode42, and the pixel20are formed on an insulating substrate40made of non-alkali glass or the like. The gate electrode42of the TFT22is connected to the scanning interconnect28(seeFIG. 2). An interconnect layer (hereinafter, referred to as a “first signal interconnect layer”) in which the scanning interconnect28and the gate electrode42are formed is formed of a laminated film made of Al or Cu, or a material using Al or Cu as a main component, but the invention is not limited thereto.

An insulating film44is formed on one surface of the first signal interconnect layer, and a portion thereof disposed on the gate electrode42acts as a gate insulating film in the TFT22. The insulating film44is formed of SiNxor the like, for example, and is formed through chemical vapor deposition (CVD), for example.

A semiconductor active layer46is formed in an island shape on the gate electrode42on the insulating film44. The semiconductor active layer46is a channel portion of the TFT22, and for example, is formed of an amorphous silicon film.

A source electrode48and a drain electrode50are formed on an upper layer thereof. The signal interconnect26together with the source electrode48and the drain electrode50are formed on the interconnect layer on which the source electrode48and the drain electrode50are formed. The source electrode48of the TFT22of the pixel20is connected to the signal interconnect26. An interconnect layer (hereinafter, referred to as a “second signal interconnect”) in which the source electrode48, the drain electrode50, and the signal interconnect26are formed is formed of a laminated film Al or Cu, or a material using Al or Cu as a main component, but the invention is not limited thereto. An impurity-added semiconductor layer (not shown) based on impurity-added amorphous silicon or the like is formed between the source electrode48and the drain electrode50, and the semiconductor active layer46. In the TFT22, the source electrode48and the drain electrode50are reversed according to polarities of collected and accumulated electric charges by a lower electrode58(which will be described later).

Hereinafter, the first signal interconnect layer and the second signal interconnect layer may be generally referred to as a TFT interconnect layer90.

On an approximately entire surface of a region (approximately entire region) in which the pixel20on the substrate40is provided, covered with the second signal interconnect, a TFT protective film layer52is formed to protect the TFT22and the signal interconnect26. The TFT protective film layer52is formed of SiNxor the like, and is formed through CVD, for example.

A coating type first flattening film54is formed on the TFT protective film layer52. The first flattening film54is formed of a photosensitive organic material of a low dielectric constant (relative dielectric constant cr=2to4), for example, with a film thickness of 1 μm to 10 μm, preferably, 1 μm to 5 μm. As such an organic material, for example, a material obtained by mixing a naphthoquinone diazide-based positive photosensitizer into a base polymer formed of a copolymer of positive photosensitive acrylic-based resin:methacrylic acid and glycidyl methacrylate is used.

The first flattening film54has a function as a flattening film, and has an effect of flattening a step of a lower layer. Further, the first flattening film54also has an effect of reducing capacitance between metals arranged on an upper layer and a lower layer of the first flattening film54. A contact hole59is formed on the first flattening film54.

The lower electrode58of the sensor unit24is formed on the first flattening film54to cover a pixel region where the pixel20is formed while filling the contact hole59. The lower electrode58is connected to the drain electrode50of the TFT22through the contact hole59. A material of the lower electrode58is not particularly limited as long as it has conductivity in a case where the semiconductor layer60(which will be described later) has a thickness of about 1 μm. Thus, the lower electrode58may be formed of a conductive metal such as an Al-based material, Indium Tin Oxide (ITO), and the like.

On the other hand, in a case where the film thickness of the semiconductor layer60is thin (about 0.2 μm to about 0.5 μm), since absorption of light is not sufficient in the semiconductor layer60, in order to prevent an increase in current leakage due to light emission to the TFT22, it is preferable that the lower electrode58is formed of an alloy in which a light shielding metal is a main component, or a laminated film.

The semiconductor layer60that functions as a photodiode is formed on the lower electrode58. In this embodiment, a photodiode of a PIN structure in which an n+layer, an i layer, and a p+layer (n+amorphous silicon, amorphous silicon, and p+amorphous silicon, which are not shown in the figure) are laminated from the substrate is employed as the semiconductor layer60. When light is emitted to the i layer, electric charges (a pair of a free electron and a free hole) are generated in the layer i layer. The n+layer and the p+layer function as contact layers, and electrically connects the lower electrode58and the upper electrode62(which will be described later) with the i layer.

The upper electrode62is individually formed on the semiconductor layer60. A material having a high light transmittance such as ITO or Indium Zinc Oxide (IZO) is used as the upper electrode62, for example. The sensor unit24of the radiation detecting device10of this embodiment includes the upper electrode62, the semiconductor layer60, and the lower electrode58.

A second flattening film64for flattening irregularities formed by the semiconductor layer60is formed on the first flattening film54. In this embodiment, the second flattening film64is formed of the same material as that of the first flattening film54with the same thickness as that thereof. The invention is not limited thereto, and the second flattening film64may be formed of a material different from that of the first flattening film54with a thickness different from that thereof. Here, the material and thickness of the second flattening film64may be the same material and thickness of the first flattening film54.

In the radiation detecting device10of this embodiment, a protective film66is formed on the second flattening film64to cover a side surface of the sensor unit24and an edge portion of the upper electrode62.

The TFT substrate14formed in this way corresponds to an example of a substrate of the disclosed technique. A surface organic film70which is an example of a first protective film of the disclosed technique is formed on the TFT substrate14. Polyimide is preferably used as the surface organic film70, for example. Preferably, the film thickness of the surface organic film70is 1 μm to 100 μm, for example.

In this embodiment, a substrate in which surface organic film70is formed on the TFT substrate14is referred to as the photoelectric conversion substrate12.

A phosphor layer82is formed on the photoelectric conversion substrate12. In this embodiment, a scintillator is used as the phosphor layer82. As the scintillator, preferably, a scintillator that generates fluorescence having a wavelength region of a relatively wide range, capable of generating light having an absorbable wavelength range is used. As such a scintillator, CsI:Na, CaWO4, YtaO4:Nb, BaFx:Eu (X is Br or Cl), LaOBr:Tm, GOS (Gd2O2S:Pr), or the like may be used. Specifically, in a case where imaging is performed using X-rays as radiation, it is preferable to use cesium iodide (CsI), and it is more preferable to use CsI:Tl (cesium iodide to which thallium is added) or CsI:Na of which a light emission spectrum in X-ray emission is 400 nm to 700 nm. A light emission peak wavelength in a visible light range of CsI:Tl is 565 nm. Further, in a case where a scintillator including CsI is used as the scintillator, it is preferable to use a scintillator formed as a columnar crystal structure of a strip form by a vacuum deposition method. Further, preferably, the thickness of the phosphor layer82is 100 μm to 800 μm.

A moisture-proof protective layer86which is an example of a second protective layer of the disclosed technique is formed on the phosphor layer82through an adhesive layer84which is an example of a resin of the disclosed technique. The adhesive layer84is not particularly limited as long as it is a resin that is curable according to application of stress (stimulus) from a flowable state, but a photocurable resin or a hot melt resin is preferably used. Normally, as the photocurable resin, a resin that is normally in a flowable state and is curable by visible light or invisible light such as infrared rays may be used. As a specific example, urethane acrylate, acrylic resin acrylate, epoxy acrylate, or the like may be used.

Further, as the hot melt resin, a resin which is normally solid and changes into a flowable state as according to application of heat may be used. As a specific example, a thermosetting plastic such as ethylene-vinyl acetate copolymer resin (EVA), ethylene-acrylic acid copolymer resin (EAA), ethylene-ethyl acrylate copolymer resin (EEA), or ethylene-methyl methacrylate copolymer (EMMA) may be used.

Further, the material is not limited to the photocurable resin or the hot melt resin, and any resin that is cured when in a flowable state may be used. For example, a thermosetting resin may be used. A viscosity in the flowable state is preferably 100 Pa·S to 10000 Pa·S.

The thickness of the adhesive layer84is preferably 5 μm to 50 μm.

A moisture-proof protective layer86has a function of protecting the radiation detecting device10from moisture or the like. InFIG. 3, an example in which the moisture-proof protective layer86is a single layer is shown, but in this embodiment, as a specific example, a two-layered moisture-proof protective layer86including a protective layer based on an organic film and a reflecting layer is used. The protective layer is provided on a side where the moisture-proof protective layer86is in contact with the adhesive layer84. An organic film of a melting point higher than that of the adhesive layer84may be used as the protective layer. As a specific example, polyethylene terephthalate (PET), polyphenylene sulfide (PPS), biaxially oriented polypropylene (OPP), polyethylene naphthalate (PEN), polyimde (PI), or the like may be used.

Further, as the reflecting layer which is a top layer of the radiation detecting device10, Al, an AL alloy, Ag, or the like may be used.

The thickness of the moisture-proof protective layer86is preferably 10 μm to 200 μm.

FIG. 4shows a plan view of the radiation detecting device10when seen from a side where the phosphor layer82is provided. Further,FIG. 5is a B-B sectional view of the radiation detecting device10shown inFIG. 4.

The phosphor layer82is provided in a central region on the photoelectric conversion substrate12(TFT substrate14). The phosphor layer82is formed to cover a region (pixel region) where the pixel20of the TFT substrate14is formed. As the size (size on the surface of the photoelectric conversion substrate12) of the phosphor layer82, specifically, 43.2 cm×43.2 cm, 35.6 cm×43.2 cm, 27.9 cm×30.5 cm, 25.4 cm×30.5 cm, or the like may used.

A sealing region92is provided between an outer edge portion of the phosphor layer82on the photoelectric conversion substrate12and an edge portion of the photoelectric conversion substrate12. The sealing region92surrounds the periphery of the phosphor layer82. The sealing region92refers to a region on the photoelectric conversion substrate12covered with the moisture-proof protective layer86to seal the phosphor layer82by the moisture-proof protective layer86. The sealing region92includes a region substantially provided due to flowing of the adhesive layer84and the moisture-proof protective layer86when sealing is performed using the moisture-proof protective layer86in addition to a region that is predetermined in design,. Further, an edge portion of the sealing region92close to the phosphor layer82is referred to as an inner periphery, and an edge portion thereof close to the photoelectric conversion substrate12(TFT substrate14) is referred to as an outer periphery.

A groove portion80is provided in the sealing region92. From a viewpoint of reducing a liquid reservoir formed by the adhesive layer84in an edge portion of the phosphor layer82, it is preferable that the groove portion80is provided at a position close to an outer edge (hereinafter, referred to as an edge portion) of the phosphor layer82. More preferably, the groove portion80is provided at a position closer to the edge portion of the phosphor layer82than to the edge portion of the photoelectric conversion substrate12. Most preferably, it is preferable that the groove portion80is provided at a position closer to the inner periphery of the sealing region92than to the outer periphery of the sealing region92.

In a case where the groove portion80is provided outside the sealing region92, there is a concern that a region where the adhesive layer84is in contact with the outside (outside air) increases and moisture intrudes from the region being in contact with the outside. Thus, the groove portion80is provided in the sealing region92.

Further, the groove portion80is provided in parallel with the edge portion of the photoelectric conversion substrate12. Here, the “parallel” includes ignorable variation due to an error in design or the like. In a case where the groove portion80is provided in a direction intersecting the edge portion of the photoelectric conversion substrate12, moisture-proof performance in a portion where the groove portion80is provided may deteriorate. As a result, there is a concern that moisture-proof performance of the radiation detecting device10deteriorates. Thus, it is preferable that the groove portion80is provided in parallel with the edge portion of the photoelectric conversion substrate12.

As a specific example of a distance (width) from the edge portion of the phosphor layer82to the outer periphery of the sealing region92, 1 mm to 10 mm may be used. It is preferable that the width of the groove portion80is 25% to 75% of the width of the sealing region92. More preferably, the width of the groove portion80is about 50% of the width of the sealing region92.

The groove portion80of this embodiment is provided in the surface organic film70, as shown inFIG. 5. More preferably, the groove portion80passes through the surface organic film70to reach the surface of the second flattening film64.

Next, a method for manufacturing the radiation detecting device10will be described.

FIG. 6is a flowchart illustrating an example of a flow of a manufacturing process of the radiation detecting device10.

First, in step S100, a substrate preparation process is performed. In the substrate preparation process, the TFT substrate14is prepared. The TFT substrate14may be prepared through preparation of the radiation detecting device10which is manufactured in advance, or may be manufactured using the substrate40as follows.

In a case where the TFT substrate14is manufactured, first, the TFT22is formed on the substrate40.

Then, the TFT protective film layer52is formed on the substrate40on which the TFT22is formed, and then, the first flattening film54is formed thereon.

Then, the contact hole59is formed in the first flattening film54. The lower electrode58is formed while filling the contact hole59, and then, the semiconductor layer60and the upper electrode62are formed thereon. In this way, the sensor unit24is formed.

Then, in order to flatten irregularities formed by the lower electrode58, the semiconductor layer60, and the upper electrode62, the second flattening film64is formed.

Then, the common interconnect29is formed on the upper electrode62.

Then, the protective film66is formed on the entire surface of the second flattening film64, the upper electrode62, and the common interconnect29.

If the TFT substrate14can be prepared, in the next step S102, the surface organic film70is formed on the TFT substrate14by a surface organic film formation process. Instead of the process of step S102, the photoelectric conversion substrate12which is manufactured in advance may be prepared. Steps S100and S102correspond to an example of a preparation process of the disclosed technique.

In the next step S104, the groove portion80is formed by a groove formation process. In this embodiment, the groove portion80is formed by processing the surface organic film70. For example, the processing of the surface organic film70may be performed with high accuracy in the unit of several micrometers by using a photolithography process.

As a specific method, a method for bonding the surface organic film70(a film made of polyimide or the like) where the groove portion80is formed by cutting in advance may be used. Further, for example, a method of masking the corresponding portion, performing a surface protection process using a crystalline polymer or the like, and performing etching may be used, for example.

In the next step S106, the phosphor layer82is formed on the photoelectric conversion substrate12by a phosphor layer formation process. As a method for forming the phosphor layer82, vacuum deposition may be used.

In the next step S108, the moisture-proof protective layer86is formed through the adhesive layer84by a moisture-proof protective layer formation process to cover the phosphor layer82and the sealing region92.

In a case where the adhesive layer84is made of a photocurable resin, the adhesive layer84is coated in the phosphor layer82and the sealing region92, and then, light is emitted thereto from the side of the substrate40of the TFT substrate14, so that the adhesive layer84is cured to cause the moisture-proof protective layer86to adhere thereto. In a case where the adhesive layer84is made of a hot melt resin, the phosphor layer82is covered with the adhesive layer84and the moisture-proof protective layer86, and then, heating and pressurization are performed, so that the adhesive layer84is melted to cause the moisture-proof protective layer86to adhere thereto.

In both cases, when the moisture-proof protective layer86is adhered through the adhesive layer84, the adhesive layer84enters a flowable state, and thus, the adhesive layer84flows into the groove portion80and fills the inside of the groove portion80. The inside of the groove portion80may not be entirely filled, and it is sufficient if the adhesive layer84at least enters the inside of the groove portion80. For example, the adhesive layer84may fill a part of the inside of the groove portion80. As the adhesive layer84enters the inside of the groove portion80, it is possible to prevent a liquid reservoir of the adhesive layer84from being formed in the edge portion of the phosphor layer82.

In this way, the radiation detecting device10of this embodiment is manufactured.

In this embodiment, an example in which the groove portion80is formed to pass through the surface organic film70and to reach the surface of the surface organic film70is shown, but the invention not limited thereto. For example, as shown inFIG. 7, the groove portion80may be formed to pass through the surface organic film70, the second flattening film64, and the first flattening film54and to reach the surface of the TFT protective film layer52. In such a case, in the groove formation process of step S104, etching may be performed until the groove portion80reaches the surface of the TFT protective film layer52.

In the radiation detecting device10shown inFIG. 7, the depth of the groove portion80is deeper than that of the radiation detecting device10shown inFIG. 5. The width of the groove portion80is limited depending on the width of the sealing region92, but since the size of the inside of the groove portion80can be set to be larger without enlarging the width of the groove portion80compared with that shownFIG. 5, it is possible to increase the amount of the adhesive layer84that flows into the inside of the groove portion80. Thus, in the radiation detecting device10of this embodiment, it is possible to make the adhesive layer84of the edge portion of the phosphor layer82thinner.

Second Embodiment

Next, a second embodiment will be described. In the radiation detecting device10of this embodiment, since the groove portion80is different from that of the first embodiment, the groove portion80will be described. The same reference numerals are given to the same portions as in the radiation detecting device10according to the first embodiment, and detailed description thereof will not be repeated.

FIG. 8is a sectional view corresponding to a B-B section inFIG. 4in the first embodiment. In the radiation detecting device10of this embodiment shown inFIG. 8, the groove portion80passes through the surface organic film70, the second flattening film64, and the first flattening film54, and reaches the surface of the TFT protective film layer52. Further, the surface organic film70is formed to cover the top of the second flattening film64and an inner side wall of the groove portion80.

When forming the groove portion80in this way, in the surface organic film formation process of step S102in the manufacturing process of the radiation detecting device10, etching is performed in portions of the first flattening film54and the second flattening film64corresponding to the groove portion80to eliminate the first flattening film54and the second flattening film64. Then, the surface organic film70is formed on the photoelectric conversion substrate12. Then, etching is performed in a portion corresponding to a bottom portion of the groove portion80to eliminate the surface organic film70, so that the surface of the TFT protective film layer52may be exposed.

The manufacturing method is not limited thereto. For example, whenever the first flattening film54and the second flattening film64are formed, sequentially, portions thereof corresponding to the groove portion80may be formed through etching. Specifically, etching is performed in a portion of the first flattening film54corresponding to the groove portion80to eliminate the first flattening film54after the first flattening film54is formed. Further, the second flattening film64is formed. After the second flattening film64is formed, etching is performed in a portion thereof corresponding to the groove portion80to eliminate the second flattening film64.

In the radiation detecting device10shown inFIG. 8, since the depth of the groove portion80is deeper than that of the radiation detecting device10shown inFIG. 5, similar to the radiation detecting device10shown inFIG. 7, it is possible to increase the amount of the adhesive layer84that flows into the inside of the groove portion80. Thus, in the radiation detecting device10of this embodiment, it is possible to make the adhesive layer84in the edge portion of the phosphor layer82thinner. Further, in the radiation detecting device10of this embodiment, it is possible to protect the surfaces of the first flattening film54and the second flattening film64by the surface organic film70, compared with the radiation detecting device10shown inFIG. 7.

Third Embodiment

Next, a third embodiment will be described. In the radiation detecting device10of this embodiment, since the groove portion80is different from that of each of the above-described embodiments, the groove portion80will be described. The same reference numerals are given to the same portions as in the radiation detecting device10according to the first embodiment, and detailed description thereof will not be repeated.

FIG. 9is a sectional view corresponding to the B-B section inFIG. 4according to the first embodiment. In the radiation detecting device10of this embodiment shown inFIG. 9, the groove portion80passes through the surface organic film70, the second flattening film64, and the first flattening film54, and reaches the surface of the TFT protective film layer52.

Further, in the radiation detecting device10of this embodiment, a configuration outside the sealing region92of the photoelectric conversion substrate12, more specifically, a configuration from the groove portion80to the edge portion of the photoelectric conversion substrate12is different from that of the first embodiment.

As shown inFIG. 9, in the radiation detecting device10of this embodiment, the first flattening film54and the second flattening film64are not provided from the groove portion80to the edge portion of the photoelectric conversion substrate12, and the surface organic film70is formed on the TFT protective film layer52.

That is, in the radiation detecting device10of this embodiment, the surface organic film70is formed to cover the first flattening film54and the second flattening film64in a partial region where the phosphor layer82is provided, using the groove portion80as a boundary. Further, the surface organic film70is formed to cover the TFT protective film layer52in a region from the groove portion80to the edge portion of the TFT substrate14.

When forming the groove portion80in this way, in the surface organic film formation process of step S102in the manufacturing process of the radiation detecting device10, etching is performed in portions corresponding to the sealing region92and a region from the sealing region92to the edge portion of the photoelectric conversion substrate12to eliminate the first flattening film54and the second flattening film64. Then, the surface organic film70is formed on the photoelectric conversion substrate12. Then, etching is performed in a bottom portion of the groove portion80, so that the surface of the TFT protective film layer52may be exposed.

The manufacturing method is not limited thereto. For example, whenever the first flattening film54and the second flattening film64are formed, the portions thereof corresponding to the sealing region92and the region from the sealing region92to the edge portion of the photoelectric conversion substrate12may be sequentially eliminated. Specifically, after the first flattening film54is formed, etching is performed in a portion thereof corresponding to the sealing region92and the region from the sealing region92to the edge portion of the photoelectric conversion substrate12to eliminate the first flattening film54. Further, the second flattening film64is formed. After the second flattening film64is formed, etching is performed in a portion thereof corresponding to the sealing region92and the region from the sealing region92to the edge portion of the photoelectric conversion substrate12to eliminate the second flattening film64.

In the radiation detecting device10shown inFIG. 9, an example in which the first flattening film54and the second flattening film64are not provided from the groove portion80to the edge portion of the photoelectric conversion substrate12, but the invention is not limited thereto. Only one of the first flattening film54and the second flattening film64may not be provided (may be eliminated).

In the radiation detecting device10shown inFIG. 9, a step is generated between a region of the surface organic film70corresponding to a lower part of the phosphor layer82and the sealing region92, and a portion of the groove portion80on the side of the phosphor layer82is inclined compared with the configurations of the above-described embodiments. Since the inclination is sealed by the moisture-proof protective layer86through the adhesive layer84, it is possible to make the adhesive layer84in the inclined portion thinner. Thus, in the radiation detecting device10of this embodiment, it is possible to prevent intrusion of moisture, and to reliably perform sealing using the moisture-proof protective layer86.

Fourth Embodiment

Next, a fourth embodiment will be described. In the radiation detecting device10of this embodiment, since the shape of the groove portion80is different from that of each of the above-described embodiments, the groove portion80will be described. The same reference numerals are given to the same portions as in the radiation detecting device10according to the first embodiment, and detailed description thereof will not be repeated.

FIG. 10shows a plan view of the radiation detecting device10according to this embodiment when seen from a side where the phosphor layer82is provided. In the radiation detecting device10of the first embodiment, the groove portion80surrounds the phosphor layer82(seeFIG. 4). On the other hand, in the radiation detecting device10of this embodiment, the groove portion80is formed in parallel with an edge portion of the photoelectric conversion substrate12along an outer peripheral side of the phosphor layer82. Specifically, as shown inFIG. 10, since the phosphor layer82is formed in a rectangular shape, four groove portions80are provided in parallel with the edge portions of the photoelectric conversion substrate12along four sides of the phosphor layer82. Here, the “parallel” includes ignorable variation due to an error in design or the like.

It is preferable that the length of the groove portion80along the side of the phosphor layer82is equal to that of the side of the phosphor layer82. Further, the position of the phosphor layer82in the width direction of the sealing region92is similar to the first embodiment (seeFIG. 4). On the other hand, it is preferable that the position of the groove portion80in the direction along the side of the phosphor layer82is set so that the side of each phosphor layer82and the side of the edge portion of the groove portion80are aligned with each other (see broken lines inFIG. 10). The alignment of the side of the phosphor layer82and the edge portion of the groove portion80includes ignorable variation due to an error in design or the like.

By forming the radiation detecting device10as shown inFIG. 10, it is possible to reduce the size of a region on the photoelectric conversion substrate12where the groove portion80is provided, compared with the radiation detecting device10of the embodiments.

As described above, in the radiation detecting device10of the respective embodiments, the groove portion80is provided in the sealing region92on the photoelectric conversion substrate12. The groove portion80is provided in the vicinity of the phosphor layer82formed on the photoelectric conversion substrate12or at a position along an outer edge periphery thereof. The moisture-proof protective layer86is provided to cover the phosphor layer82and the sealing region92through the adhesive layer84.

The adhesive layer84is cured through a flowable state, and thus, functions as an adhesive. In a case where the moisture-proof protective layer86is adhered, since the adhesive layer84is in the flowable state, the adhesive layer84flows into the inside of the groove portion80, and fills at least a part of the inside of the groove portion80.

Thus, a liquid reservoir due to the adhesive layer84is generated at an edge portion of the phosphor layer82, and thus, it is possible to prevent the thickness of the adhesive layer84in the edge portion of the phosphor layer82from increasing. As a comparative example with respect to the radiation detecting device10of the above-described embodiments,FIG. 11shows a sectional view including an edge portion of a phosphor layer in a radiation detecting device in which a groove portion is not provided. In the radiation detecting device100of the comparative example shown inFIG. 11, similar to the radiation detecting device10of the above-described embodiments, a surface organic film170is formed on a photoelectric conversion substrate112, and a phosphor layer182is provided on a photoelectric conversion substrate112. Further, in the radiation detecting device100of the comparative example, a configuration in which a moisture-proof protective layer186is provided through an adhesive layer184to cover the phosphor layer182and a sealing region192is similar to that of the radiation detecting device10of the above-described embodiments. However, as understood from comparison between the radiation detecting device100shown inFIG. 11and the radiation detecting device10of the above-described embodiments (seeFIGS. 5, 7, 8, and 9), since the groove portion80is not provided in the radiation detecting device100of the comparative example, a liquid reservoir of the adhesive layer184is generated in an edge portion of a phosphor layer182. In the radiation detecting device100of the comparative example, the liquid reservoir is generated in this way, the thickness of the adhesive layer184increases, and thus, moisture from the outside easily intrudes. Thus, there is a concern that durability performance of the radiation detecting device100of the comparative example deteriorates.

On the other hand, in the radiation detecting device10of the above-described embodiments, the groove portion80is provided in the sealing region92of the photoelectric conversion substrate12. In a case where the moisture-proof protective layer86is adhered through the adhesive layer84, since the adhesive layer84flows into the inside of the groove portion80in the flowable state, it is possible to prevent a liquid reservoir due to the adhesive layer84from being generated at an edge portion of the phosphor layer82. Further, as the adhesive layer84flows into the inside of the groove portion80, it is possible to reduce the thickness of the adhesive layer84in the sealing region92. Accordingly, it is possible to prevent intrusion of moisture from the outside of the radiation detecting device10, to thereby enhance durability performance of the radiation detecting device10.

In the above-described embodiments, as shown inFIG. 1, a case where the pixels20are arranged on a matrix in two dimensions is described, but the arrangement of the pixels20is not limited thereto, and for example, may be arranged in one dimension or in a honeycomb form. In addition, the shape of the pixel is not limited, and may be a rectangular shape or a polygonal shape such as a hexagon.

Further, the shape or the like of the phosphor layer82is not limited to the above-described embodiments. In the above-described embodiments, a case where the shape is a rectangular shape is described, but for example, the shape may be a polygonal shape or a circular shape. It is sufficient if the phosphor layer82is provided to cover an upper surface of a region (pixel region) where the pixels20of the photoelectric conversion substrate12are provided.

In addition, the material of the surface organic film70is not limited to the above-described embodiments. For example, the material of the surface organic film70is exchangeable with a crystalline polymer material such as polyparaxylylene (Parylene: trademark of Union Carbide), polyurea, or polyamide.

Furthermore, the configuration, the operation and the like of the radiation detecting device10described in the embodiments are examples, and may be modified as necessary in a range without departing from the concept of the invention.

The disclosure of Japanese Patent Application No. 2014-070543 is entirely incorporated in this description by reference.

Entire documents, patent applications, and technical standards written in this description are incorporated in this description by reference to the same degree as in a case where the respective documents, patent applications, and technical standards are specifically and individually written to be incorporated by reference.