JP2017111082A - Radiation detector and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiation detector capable of saving space and improving the moisture-proof performance, and provide a manufacturing method of the detector.SOLUTION: A radiation detector of an embodiment includes: an array substrate having a plurality of photoelectric conversion elements; a scintillator layer that is disposed on the plurality of photoelectric conversion elements, and converts radiation into fluorescent light; a base portion that is disposed on the array substrate, has a frame shape in the plan view, and surrounds the scintillator layer; an overhang portion that is disposed on the base portion integrally with the base portion, and projects from the base portion toward the scintillator layer; and a moisture-proof body that covers the upside of the scintillator layer, and has a periphery whose vicinity is bonded to the top surface of at least the overhang portion.SELECTED DRAWING: Figure 2

Description

  Embodiments described herein relate generally to a radiation detector and a manufacturing method thereof.

An example of the radiation detector is an X-ray detector. The X-ray detector includes a substrate made of a light-transmitting material such as glass, a plurality of photoelectric conversion units provided in a matrix on the substrate, and covers the plurality of photoelectric conversion units so that X-rays are visible. A scintillator layer that converts light, that is, fluorescence, and a moisture-proof body that covers the scintillator layer are provided.
In some cases, a reflective layer is further provided on the scintillator layer in order to improve the use efficiency of fluorescence and improve sensitivity characteristics.

Here, the scintillator layer and the reflective layer need to be isolated from the external atmosphere in order to suppress degradation of resolution characteristics due to water vapor or the like. In particular, when the scintillator layer is made of CsI (cesium iodide): Tl (thallium), CsI: Na (sodium), or the like, resolution characteristics may be deteriorated due to humidity or the like.
For this reason, a technique has been proposed in which the scintillator layer and the reflective layer are covered with a hat-shaped moisture-proof body, and the collar portion of the moisture-proof body is joined to the substrate.
If the scintillator layer and the reflective layer are covered with a hat-shaped moisture-proof body and the collar portion of the moisture-proof body is joined to the substrate, high moisture-proof performance can be obtained.

In this case, in order to ensure the sealing performance between the flange portion of the hat-shaped moisture-proof body and the substrate and to obtain high reliability, it is preferable to increase the width dimension of the collar portion of the moisture-proof body.
However, when the width dimension of the collar portion of the moisture-proof body is increased, an extra space corresponding to the width dimension is required. In addition, it is difficult to control the amount of adhesive that protrudes outward from the collar portion of the moisture-proof body. Further, the wiring pads that are electrically connected to the flexible printed board need to be provided on the outer side in consideration of the adhesive protruding.
Therefore, if the width dimension of the collar portion of the moisture-proof body is increased and an area where the adhesive protrudes is to be secured, the dimension of the area that needs to be provided around the effective pixel area increases, and thus the X-ray detector. There is a risk of causing an increase in the size and weight.

Further, a structure has been proposed in which an encircling ring surrounding the scintillator layer is provided and a cover is bonded to the upper surface of the encircling ring.
In this case, in order to ensure the sealing property between the upper surface of the surrounding ring and the cover and to obtain high reliability, it is preferable to increase the width dimension of the surrounding ring.
However, when the width of the surrounding ring is increased, the size of the region that needs to be provided around the effective pixel area increases, which may increase the size and weight of the X-ray detector.
Further, with such a structure, it is difficult to obtain high moisture-proof performance.

JP 2009-128023 A JP 2001-1888086 A JP-A-5-242841

  The problem to be solved by the present invention is to provide a radiation detector capable of saving space and improving moisture-proof performance and a method for manufacturing the same.

  The radiation detector according to the embodiment is provided on an array substrate having a plurality of photoelectric conversion elements, a scintillator layer that is provided on the plurality of photoelectric conversion elements and converts radiation into fluorescence, and on the array substrate. A base portion that surrounds the scintillator layer in plan view, an overhang portion that is provided integrally with the base portion on the base portion, and protrudes from the base portion toward the scintillator layer, and the scintillator layer A moisture-proof body that covers the upper part and has a peripheral edge portion joined to at least the upper surface of the overhang portion.

1 is a schematic perspective view for illustrating an X-ray detector 1 according to a first embodiment. 1 is a schematic cross-sectional view of an X-ray detector 1. FIG. It is a schematic cross section for illustrating the wall body 19 which concerns on other embodiment. It is a schematic cross section for illustrating the wall body 29 which concerns on other embodiment. It is a schematic cross section for illustrating the moisture-proof body 17 which concerns on other embodiment. It is a schematic cross section for illustrating the moisture-proof body 27 which concerns on other embodiment. It is a schematic cross section for illustrating the reflective layer 16 which concerns on other embodiment. It is a schematic cross section of the X-ray detector 51 which concerns on a comparative example. It is a graph for demonstrating the change of the moisture permeation amount in a high-temperature, high-humidity environment (60 degreeC-90% RH). It is a graph for demonstrating the change of the resolution characteristic in a high-temperature, high-humidity environment (60 degreeC-90% RH).

Hereinafter, embodiments will be illustrated with reference to the drawings. In addition, in each drawing, the same code | symbol is attached | subjected to the same component and detailed description is abbreviate | omitted suitably.
Moreover, the radiation detector according to the embodiment of the present invention can be applied to various types of radiation such as γ rays in addition to X-rays. Here, as an example, a case of X-rays as a representative example of radiation will be described as an example. Therefore, by replacing “X-ray” in the following embodiments with “other radiation”, the present invention can be applied to other radiation.

(First embodiment)
First, the X-ray detector 1 according to the first embodiment is illustrated.
FIG. 1 is a schematic perspective view for illustrating the X-ray detector 1 according to the first embodiment.
In order to avoid complication, in FIG. 1, the reflection layer 6, the moisture-proof body 7, the bonding layer 8, the wall body 9, and the like are omitted.
FIG. 2 is a schematic cross-sectional view of the X-ray detector 1.
In FIG. 2, the control line (or gate line) 2c1, the data line (or signal line) 2c2, the signal processing unit 3, the image transmission unit 4 and the like are omitted in order to avoid complication. .
The X-ray detector 1 that is a radiation detector is an X-ray flat sensor that detects an X-ray image that is a radiation image. The X-ray detector 1 can be used for general medical purposes, for example. However, the use of the X-ray detector 1 is not limited to general medical use.

As shown in FIGS. 1 and 2, the X-ray detector 1 includes an array substrate 2, a signal processing unit 3, an image transmission unit 4, a scintillator layer 5, a reflective layer 6, a moisture barrier 7, a bonding layer 8, and a wall. A body 9 is provided.
The array substrate 2 includes a substrate 2a, a photoelectric conversion unit 2b, a control line 2c1, a data line 2c2, and a protective layer 2f.

The substrate 2a has a plate shape and is made of a translucent material such as non-alkali glass.
A plurality of photoelectric conversion units 2b are provided on one surface of the substrate 2a.
The photoelectric conversion unit 2b has a rectangular shape and is provided in a region defined by the control line 2c1 and the data line 2c2. The plurality of photoelectric conversion units 2b are arranged in a matrix.
One photoelectric conversion unit 2b corresponds to one pixel.

Each of the plurality of photoelectric conversion units 2b is provided with a photoelectric conversion element 2b1 and a thin film transistor (TFT) 2b2 which is a switching element.
In addition, a storage capacitor (not shown) that stores the signal charge converted in the photoelectric conversion element 2b1 can be provided. The storage capacitor (not shown) has, for example, a rectangular flat plate shape and can be provided under each thin film transistor 2b2. However, depending on the capacitance of the photoelectric conversion element 2b1, the photoelectric conversion element 2b1 can also serve as a storage capacitor (not shown).

The photoelectric conversion element 2b1 can be, for example, a photodiode.
The thin film transistor 2b2 performs switching between accumulation and emission of electric charges generated when fluorescence enters the photoelectric conversion element 2b1. The thin film transistor 2b2 can include a semiconductor material such as amorphous silicon (a-Si) or polysilicon (P-Si). The thin film transistor 2b2 has a gate electrode, a source electrode, and a drain electrode. The gate electrode of the thin film transistor 2b2 is electrically connected to the corresponding control line 2c1. The source electrode of the thin film transistor 2b2 is electrically connected to the corresponding data line 2c2. The drain electrode of the thin film transistor 2b2 is electrically connected to the corresponding photoelectric conversion element 2b1 and a storage capacitor (not shown).

A plurality of control lines 2c1 are provided in parallel with each other at a predetermined interval. For example, the control line 2c1 extends in the row direction.
One control line 2c1 is electrically connected to one of a plurality of wiring pads 2d1 provided near the periphery of the substrate 2a. One wiring pad 2d1 is electrically connected to one of a plurality of wirings provided on the flexible printed board 2e1. The other ends of the plurality of wirings provided on the flexible printed circuit board 2e1 are electrically connected to a control circuit (not shown) provided on the signal processing unit 3, respectively.

A plurality of data lines 2c2 are provided in parallel with each other at a predetermined interval. The data line 2c2 extends, for example, in the column direction orthogonal to the row direction.
One data line 2c2 is electrically connected to one of a plurality of wiring pads 2d2 provided near the periphery of the substrate 2a. One wiring pad 2d2 is electrically connected to one of a plurality of wirings provided on the flexible printed board 2e2. The other ends of the plurality of wirings provided on the flexible printed board 2e2 are electrically connected to an amplification / conversion circuit (not shown) provided on the signal processing unit 3, respectively.

The protective layer 2f is provided so as to cover the photoelectric conversion unit 2b, the control line 2c1, and the data line 2c2.
The protective layer 2f can be formed of an insulating material such as silicon nitride (SiN) or acrylic resin.

The signal processing unit 3 is provided on the side of the substrate 2a opposite to the side on which the photoelectric conversion unit 2b is provided.
The signal processing unit 3 is provided with a control circuit (not shown) and an amplification / conversion circuit (not shown).
A control circuit (not shown) controls the operation of each thin film transistor 2b2, that is, the on state and the off state of each thin film transistor 2b2. For example, a control circuit (not shown) sequentially applies the control signal S1 to each control line 2c1 via the flexible printed board 2e1, the wiring pad 2d1, and the control line 2c1. The thin film transistor 2b2 is turned on by the control signal S1 applied to the control line 2c1, and the image data signal S2 from the photoelectric conversion unit 2b can be received.

An amplification / conversion circuit (not shown) includes, for example, a plurality of charge amplifiers, a parallel / serial converter, and an analog-digital converter.
The plurality of charge amplifiers are electrically connected to each data line 2c2.
The plurality of parallel / serial converters are electrically connected to the plurality of charge amplifiers, respectively.
The plurality of analog-digital converters are electrically connected to the plurality of parallel / serial converters, respectively.
A plurality of charge amplifiers (not shown) sequentially receive the image data signal S2 from each photoelectric conversion unit 2b via the data line 2c2, the wiring pad 2d2, and the flexible printed board 2e2.

A plurality of charge amplifiers (not shown) sequentially amplify the received image data signal S2.
A plurality of parallel / serial converters (not shown) sequentially convert the amplified image data signal S2 into a serial signal.
A plurality of analog-digital converters (not shown) sequentially convert the image data signal S2 converted into a serial signal into a digital signal.

  The image transmission unit 4 is electrically connected to an amplification / conversion circuit (not shown) of the signal processing unit 3 via a wiring 4a. The image transmission unit 4 may be integrated with the signal processing unit 3. The image transmission unit 4 configures an X-ray image based on the image data signal S2 converted into a digital signal by a plurality of analog-digital converters (not shown). The configured X-ray image data is output from the image transmission unit 4 to an external device.

The scintillator layer 5 is provided on the plurality of photoelectric conversion elements 2b1, and converts incident X-rays into visible light, that is, fluorescence.
The scintillator layer 5 can be formed using, for example, cesium iodide (CsI): thallium (Tl) or sodium iodide (NaI): thallium (Tl). In this case, if the scintillator layer 5 is formed using a vacuum deposition method or the like, the scintillator layer 5 made of an aggregate of a plurality of columnar crystals is formed.
The thickness dimension of the scintillator layer 5 can be about 600 μm, for example. The thickness dimension of the pillars (pillars) of the columnar crystals can be, for example, about 8 μm to 12 μm on the outermost surface.

Here, when the scintillator layer 5 is formed by using the vacuum vapor deposition method, a vapor deposition mask having an opening of almost the same size as the region where the scintillator layer 5 is formed is used. Therefore, the inclined part 5a is formed in the peripheral part of the scintillator layer 5 by the shadow effect at the time of vacuum deposition (refer FIG. 2).
The thickness dimension of the inclined portion 5 a is gradually reduced toward the outside of the scintillator layer 5. When the thickness dimension of the inclined portion 5a changes, the emission luminance and DQE (Detective Quantum Efficiency) change according to the change in the thickness dimension. Therefore, if the inclined portion 5a is on the effective pixel region A, the image quality in the region where the inclined portion 5a is present may be deteriorated. Therefore, the inclined portion 5a of the scintillator layer 5 is preferably located outside the effective pixel region A.

The scintillator layer 5 can also be formed using, for example, gadolinium oxysulfide (Gd ₂ O ₂ S). In this case, for example, the scintillator layer 5 can be formed as follows. First, particles made of gadolinium oxysulfide are mixed with a binder material. Next, the mixed material is applied so as to cover the effective pixel region A. Next, the applied material is baked. In the case where the resolution characteristics are particularly important, a groove portion is then formed in the fired material using a blade dicing method or the like. At this time, a matrix-like groove portion can be formed so that the quadrangular columnar scintillator layer 5 is provided for each of the plurality of photoelectric conversion portions 2b. The groove portion can be filled with air (air) or an inert gas such as nitrogen gas for preventing oxidation. Moreover, you may make it a groove part be in a vacuum state. These groove portions reduce optical crosstalk between the columnar scintillators (light guide effect), so that the resolution characteristics can be improved.

  The reflective layer 6 is provided in order to improve the use efficiency of fluorescence and improve sensitivity characteristics. In other words, the reflection layer 6 reflects the light emitted from the scintillator layer 5 toward the side opposite to the side where the photoelectric conversion unit 2b is provided, and is directed toward the photoelectric conversion unit 2b.

The reflective layer 6 covers the X-ray incident side of the scintillator layer 5.
The reflective layer 6 can be formed, for example, by applying a resin containing light scattering particles made of titanium oxide (TiO ₂ ) or the like on the scintillator layer 5. The reflective layer 6 can also be formed by depositing a layer made of a metal having a high light reflectance such as a silver alloy or aluminum on the scintillator layer 5. Moreover, the reflective layer 6 can also be formed using the board which the surface consists of a metal with high light reflectivity, such as a silver alloy and aluminum, for example.

The reflective layer 6 illustrated in FIG. 2 is formed by applying a material prepared by mixing a submicron powder made of titanium oxide, a binder resin, and a solvent to the X-ray incident side of the scintillator layer 5. Is formed by drying.
In this case, the thickness dimension of the reflective layer 6 can be about 120 μm.
The reflective layer 6 is not necessarily required, and may be provided as necessary.
Below, the case where the reflection layer 6 is provided is illustrated.

The moisture-proof body 7 is provided to suppress deterioration of the characteristics of the reflective layer 6 and the scintillator layer 5 due to water vapor contained in the air.
The moisture-proof body 7 covers the scintillator layer 5 and the reflective layer 6. In this case, there may be a gap between the moisture-proof body 7 and the upper surface of the reflective layer 6, or the moisture-proof body 7 and the upper surface of the reflective layer 6 may be in contact with each other.
For example, if the moisture-proof body 7 and the upper surface of the wall body 9 (overhang portion 9b) are joined in an environment whose pressure is lower than the atmospheric pressure, the moisture-proof body 7 and the upper surface of the reflective layer 6 come into contact with each other due to the atmospheric pressure.

The vicinity of the periphery of the moisture-proof body 7 is joined to the upper surface of the wall body 9 (overhang portion 9b).
The moisture-proof body 7 can be any of a film-like body, a foil-like body, and a thin plate.
The moisture-proof body 7 can be formed from a material having a small moisture permeability coefficient.
The moisture-proof body 7 is formed by laminating, for example, aluminum, an aluminum alloy, or a resin film and a film made of an inorganic material (metal such as aluminum or aluminum alloy, ceramic material such as SiO ₂ , SiON, Al ₂ O ₃ ). Further, it can be formed from a low moisture-permeable moisture-proof film (water vapor barrier film).
In this case, if the moisture-proof body 7 is formed using aluminum, an aluminum alloy or the like whose effective moisture permeability coefficient is almost zero, water vapor that permeates the moisture-proof body 7 can be almost completely eliminated.

Further, the thickness dimension of the moisture-proof body 7 can be determined in consideration of X-ray absorption and rigidity. In this case, if the thickness dimension of the moisture-proof body 7 is too large, the absorption of X-rays becomes too large. If the thickness dimension of the moisture-proof body 7 is too small, the rigidity is lowered and it is easy to break.
The moisture-proof body 7 can be formed using, for example, an aluminum foil having a thickness dimension of 0.1 mm.

The bonding layer 8 is provided between the overhang portion 9 b and the moisture-proof body 7, and joins the vicinity of the periphery of the moisture-proof body 7 and the wall body 9. The bonding layer 8 can also cover the outer side (outer surface of the wall body 9) or the inner side (upper part of the reflective layer 6 or the scintillator layer 5) from the overhang portion 9b as long as it is within a certain range.
The bonding layer 8 can be formed, for example, by curing any one of a delayed curable adhesive, a natural (normal temperature) curable adhesive, and a heat curable adhesive.
Further, the bonding layer 8 can further include a filler material and a hygroscopic material made of an inorganic material to be described later. If the bonding layer 8 includes a filler material or a hygroscopic material made of an inorganic material, water vapor contained in the air can be prevented from passing through the bonding layer 8 and reaching the scintillator layer 5.

The wall body 9 has a base portion 9a and an overhang portion 9b.
The base 9a has a frame shape in plan view and surrounds the scintillator layer 5. The base portion 9a is provided outside the scintillator layer 5 and inside the region where the wiring pads 2d1 and 2d2 are provided. The base 9 a is provided on the array substrate 2 and is in close contact with the array substrate 2.
The overhang portion 9b is provided on the base portion 9a. The overhang portion 9b is provided integrally with the base portion 9a. The overhang portion 9 b protrudes from the base portion 9 a toward the scintillator layer 5. The overhang portion 9 b is in close contact with the reflective layer 6 provided on the inclined portion 5 a of the scintillator layer 5. When the reflective layer 6 is not provided, the overhang portion 9 b is in close contact with the peripheral end surface 5 a 1 of the scintillator layer 5.

Providing the overhang portion 9b over the inclined portion 5a of the scintillator layer 5 effectively uses the upper space of the inclined portion 5a to improve moisture resistance and reliability.
If the overhang portion 9b is provided, the space between the base portion 9a and the inclined portion 5a of the scintillator layer 5 can be filled, so that the water vapor contained in the air is prevented from reaching the scintillator layer 5. it can. In addition, since the bonding area between the moisture-proof body 7 and the wall body 19 can be increased, the invasion of water vapor from the bonding interface between the moisture-proof body 7 and the wall body 19 can be suppressed, so that the moisture-proof performance can be improved. Furthermore, since the bonding strength between the moisture-proof body 7 and the wall body 19 is increased by the increase in area, it is highly resistant to the thermal stress caused by the difference in thermal expansion between the structural members due to changes in environmental temperature. Become.
On the other hand, even if the overhang portion 9 b is provided, the distance between the base portion 9 a and the inclined portion 5 of the scintillator layer 5 is not changed. Therefore, the size of the area provided around the effective pixel area A is not affected.
Even if the overhang portion 9b is formed, the dimension of the effective pixel area A is not affected. In addition, the size of the X-ray detector 1 does not increase. In addition, it is possible to provide a moisture-proof structure with higher moisture resistance and reliability.

  If the overhang portion 9b is provided, it is easy to secure a region where the bonding layer 8 is provided. In this case, the upper surface of the overhang portion 9b is preferably flat. If the upper surface of the overhang portion 9b is flat, it becomes easy to secure the sealing property between the overhang portion 9b and the moisture-proof body 7 and to obtain high reliability.

  The base portion 9a and the overhang portion 9b can be formed from the same material. If the base portion 9a and the overhang portion 9b are formed from the same material, it is possible to suppress the formation of an interface between the base portion 9a and the overhang portion 9b. If an interface is not formed between the base portion 9a and the overhang portion 9b, it is possible to prevent water vapor contained in the air from entering the inside of the wall body 9 through the interface. Further, the bonding strength between the base portion 9a and the overhang portion 9b can be increased.

The base portion 9a and the overhang portion 9b can be formed from a material having a low moisture permeability coefficient. The base 9a and the overhang 9b can include, for example, a filler material made of an inorganic material and a resin (for example, an epoxy resin).
In this case, the inorganic material is, for example, a silicate mineral, silicon oxide, aluminum oxide, silicon nitride, aluminum nitride, silicon carbide, aluminum carbide, a composite compound containing at least silicon and oxygen, aluminum, and a specific gravity higher than aluminum. It can be a small metal.
The silicate mineral can be, for example, talc (talc: Mg ₃ Si ₄ O ₁₀ (OH) ₂ ).
The composite compound containing at least silicon and oxygen can be, for example, Si—O—N, Si—O—C, Si—Al—O, Si—Al—O—N, or the like.

In this case, talc is an inorganic material with low hardness and high slipperiness. Therefore, even if talc is contained at a high concentration, the base portion 9a and the overhang portion 9b do not become brittle.
Moreover, the density | concentration of a talc can be raised if the size and particle size distribution are optimized so that the particle size of the filler material which consists of talc may be about several micrometers to several tens of micrometers.
If the concentration of talc is increased, the moisture permeability coefficient can be reduced by about one digit as compared with the case of using only resin.

Further, the base 9a and the overhang 9b may include a hygroscopic material and a resin (for example, an epoxy resin).
The material for forming the base portion 9a and the overhang portion 9b can be prepared by mixing calcium chloride as a hygroscopic material, a resin (for example, an epoxy resin) and a solvent, for example.
In this case, for example, the density can be about 2.1 g / cc, and the moisture absorption capacity per unit weight can be about 27%.

Further, the overhang portion 9b may include a phosphor material (corresponding to an example of the first phosphor material) that converts X-rays into fluorescence and a resin (for example, an epoxy resin). Note that the base portion 9a may include a phosphor material or may not include a phosphor material. Even when the base portion 9a does not contain a phosphor material, if the resin contained in the base portion 9a and the resin contained in the overhang portion 9b are the same, there is an interface between the base portion 9a and the overhang portion 9b. The formation can be suppressed.
Further, when the overhang portion 9b including the phosphor material is used, a part of the overhang portion 9b overlaps the inclined portion 5a in plan view. Further, the reflective layer 6 is not provided on the inclined portion 5 a of the scintillator layer 5. That is, the reflective layer 6 is not provided between the overhang portion 9b and the inclined portion 5a (see, for example, FIG. 7).

The phosphor material is not particularly limited as long as it can convert X-rays into fluorescence.
Examples of the phosphor material include cesium iodide: thallium, sodium iodide: thallium, gadolinium oxysulfide: terbium (Tb), and zinc sulfide (ZnS): copper (Cu). The phosphor material included in the overhang portion 9b may be different from or the same as the phosphor material (corresponding to an example of the second phosphor material) included in the scintillator layer 5. May be. However, the phosphor material included in the overhang portion 9 b is preferably the same as the phosphor material included in the scintillator layer 5. In this way, it becomes easy to reduce the difference in emission luminance and the characteristic difference due to X-ray energy.

  As described above, the light emission luminance is reduced in the inclined portion 5a of the scintillator layer 5. If the phosphor material is included in the overhang portion 9b, the emission luminance reduced in the inclined portion 5a can be compensated by the emission luminance of the fluorescence generated in the overhang portion 9b. Therefore, if the phosphor material is included in the overhang portion 9b, the inclined portion 5a of the scintillator layer 5 can be positioned on the effective pixel region A (see, for example, FIG. 7). As a result, it is possible to reduce the size of the area that needs to be provided around the effective pixel area A.

Here, in the central region of the scintillator layer 5 and the region where the overhang portion 9b and the inclined portion 5a are provided, the light emission luminance may not be equal.
In addition, a certain luminance difference is generated between the inner side and the outer side of the peripheral edge of the reflective layer 6 depending on whether the reflective layer 6 covers the entire overhang portion 9b, partially covers it, or does not cover it.

However, in the image transmission unit 4 described above, electrical processing (image correction, sensitivity correction) for correcting a sensitivity difference caused by a luminance difference when constructing an X-ray image can be performed.
Therefore, if the luminance difference between the central region of the scintillator layer 5 and the region where the overhang portion 9b and the inclined portion 5a are provided is within a predetermined range, there is no problem in image quality.

The scintillator layer 5 is composed of an aggregate of a plurality of columnar crystals. Therefore, in the scintillator layer 5, since the spread of light emission is suppressed, the resolution characteristics are improved.
On the other hand, since the overhang portion 9 b does not have a columnar crystal, there is a possibility that the spread of light emission becomes larger than that of the scintillator layer 5. For this reason, the region where the overhang portion 9 b and the inclined portion 5 a are provided may have poor resolution characteristics as compared with the central region of the scintillator layer 5.
However, in general, important detection is performed in the central area of the effective pixel area A, and in the peripheral area of the effective pixel area A (area where the overhang portion 9b and the inclined portion 5a are provided) For example, a contour is determined. That is, it is unlikely that important detection that requires a high-definition image is performed in the peripheral region of the effective pixel region A, and if the resolution characteristics in the peripheral region of the effective pixel region A are slightly reduced, the detection is practical. There is no problem.
That is, there is no practical problem even if there is a difference in resolution characteristics within a predetermined range between the central region of the scintillator layer 5 and the region where the overhang portion 9b and the inclined portion 5a are provided.

  According to the knowledge obtained by the present inventors, if the ratio of the phosphor material contained in the overhang portion 9b is set to 40% or more by volume filling rate, there will be a practical problem in luminance and resolution characteristics. There is no. In this case, it is more desirable that the ratio of the phosphor material contained in the overhang portion 9b is 60% or more in terms of volume filling rate.

  In addition, many phosphor materials made of a sintered body have a low moisture permeability coefficient compared to general resins. Therefore, if the base portion 9a and the overhang portion 9b including the phosphor material are provided, the moisture permeability coefficient can be reduced as compared with the case of the base portion 9a and the overhang portion 9b including only the resin material. If the moisture permeability coefficient can be reduced, water vapor contained in the air can be prevented from passing through the base portion 9a and the overhang portion 9b to reach the scintillator layer 5. Therefore, it is possible to suppress deterioration of the characteristics of the scintillator layer 5 due to water vapor contained in the air.

As described above, the base portion 9a and the overhang portion 9b only need to contain at least one of a filler material, a hygroscopic material, and a phosphor material made of an inorganic material.
Moreover, epoxidized vegetable oils, such as an epoxidized linseed oil, can also be further added to the material for forming the base part 9a and the overhang part 9b. If an epoxidized vegetable oil is added, the base 9a and the overhang part 9b which have flexibility can be formed. If the base portion 9a and the overhang portion 9b have flexibility, even if thermal stress occurs between the base portion 9a and the array substrate 2 and between the overhang portion 9b and the scintillator layer 5, the flexibility The occurrence of peeling can be suppressed.

  When forming the base portion 9 a, a material for forming the base portion 9 a is applied on the array substrate 2 in a frame shape so as to surround the scintillator layer 5. When the overhang portion 9b is formed, a material for forming the overhang portion 9b is applied on the base portion 9a. Application | coating of material can be performed using a dispenser apparatus etc., for example. Details regarding the formation of the base portion 9a and the overhang portion 9b will be described later.

FIG. 3 is a schematic cross-sectional view for illustrating a wall body 19 according to another embodiment.
As shown in FIG. 3, the wall body 19 has a base portion 9a and an overhang portion 9b1. The base portion 9a and the overhang portion 9b1 are integrated.
The overhang portion 9b1 is provided on the base portion 9a. The overhang portion 9b1 protrudes from the base portion 9a toward the scintillator layer 5. The material of the overhang portion 9b1 can be the same as the material of the overhang portion 9b described above. The overhang portion 9 b 1 is in close contact with the reflective layer 6 provided on the inclined portion 5 a of the scintillator layer 5. Note that, when the reflective layer 6 is not provided, the overhang portion 9 b 1 is in close contact with the peripheral end surface 5 a 1 of the scintillator layer 5.

  However, a gap 19 a is provided between the overhang portion 9 b 1 and the array substrate 2. The gap 19a can be provided continuously so as to exhibit a frame shape in plan view, or can be provided intermittently. If the gap 19a is provided, the contact area between the overhang portion 9b1 and the reflective layer 6 provided on the inclined portion 5a (in the case where the reflective layer 6 is not provided, the overhang portion 9b1 and the peripheral end surface) The contact area with 5a1 can be reduced. Therefore, even if a thermal stress is generated between the overhang portion 9b1 and the scintillator layer 5, it is possible to suppress peeling.

  If a material having a high viscosity is applied onto the base portion 9a when forming the overhang portion 9b1, it is possible to suppress the applied material from flowing to the array substrate 2 side. Therefore, the overhang portion 9b1 and the gap 19a can be formed by appropriately adjusting the viscosity of the material for forming the overhang portion 9b.

FIG. 4 is a schematic cross-sectional view for illustrating a wall body 29 according to another embodiment.
As shown in FIG. 4, the wall body 29 has a base portion 9a and an overhang portion 9b2. The base portion 9a and the overhang portion 9b2 are integrated.
The overhang portion 9b2 is provided on the base portion 9a. The overhang portion 9b2 protrudes from the base portion 9a toward the scintillator layer 5. The material of the overhang portion 9b2 can be the same as the material of the overhang portion 9b described above.

  A gap 29 a is provided between the overhang portion 9 b 2 and the reflective layer 6 provided on the inclined portion 5 a of the scintillator layer 5. When the reflective layer 6 is not provided, a gap 29 a is provided between the overhang portion 9 b 2 and the peripheral end surface 5 a 1 of the scintillator layer 5.

The gap 29a can be provided continuously or intermittently. That is, the overhang portion 9b2 and the inclined portion 5a may not be in contact at all, or a part thereof may be in close contact.
If the gap 29a is provided, the contact area between the overhang portion 9b2 and the reflective layer 6 provided on the inclined portion 5a (in the case where the reflective layer 6 is not provided, the overhang portion 9b2 and the peripheral end surface). The contact area with 5a1 can be reduced. Therefore, it is possible to prevent the occurrence of stress caused by the difference in thermal expansion between the overhang portion 9b2 and the scintillator layer 5 due to a change in environmental temperature or the like. As a result, it is possible to suppress the scintillator layer 5 from being damaged or the wall body 29 and the scintillator layer 5 from being peeled off from the substrate 2a.

  If a material having a high viscosity is applied on the base 9a when the overhang portion 9b2 is formed, the applied material can be prevented from flowing to the array substrate 2 side. In this case, if the amount of application at one time is reduced (the thickness dimension of the layer formed by one application is reduced), the shape and outer dimensions of the overhang portion 9b2 can be easily controlled. Therefore, the overhang part 9b2 and the gap 29a can be formed by appropriately adjusting the viscosity of the material for forming the overhang part 9b, the amount of application once, and the number of applications.

FIG. 5 is a schematic cross-sectional view for illustrating a moisture-proof body 17 according to another embodiment.
As shown in FIG. 5, a bent portion 17 a that protrudes toward the substrate 2 a is provided near the periphery of the moisture-proof body 17.
The bent portion 17 a is provided so as to surround the periphery of the moisture-proof body 17.
The bent portion 17a is bonded to the upper surface of the overhang portion 9b through the bonding layer 8. If the moisture-proof body 17 has the bent portion 17a, the rigidity can be increased.
Further, when the moisture-proof body 17 is joined to the upper surface of the overhang portion 9b, positioning can be performed by fitting the bent portion 17a into the concave portion provided on the upper surface of the overhang portion 9b.

Therefore, it is possible to improve workability and joining accuracy when joining the moisture-proof body 17 to the upper surface of the overhang portion 9b.
Further, if the bent portion 17a is provided, the bonding area can be increased. Therefore, it is possible to improve the bonding strength and the moisture proof performance.

FIG. 6 is a schematic cross-sectional view for illustrating a moisture-proof body 27 according to another embodiment.
As shown in FIG. 6, the moistureproof body 27 is provided with an embossed stress absorbing portion 27a. A surface 27a1 opposite to the scintillator layer 5 side of the stress absorbing portion 27a (surface on which X-rays are incident) 27a1 protrudes from a surface 27b of the moisture-proof body 27 opposite to the scintillator layer 5 side.
The surface 27a2 on the scintillator layer 5 side of the stress absorbing portion 27a protrudes from the surface 27c on the scintillator layer 5 side of the moisture-proof body 7 in the same direction as the surface 27a1.

The thickness dimension of the stress absorbing portion 27a is substantially the same as the thickness dimension of the moisture-proof body 27 other than the stress absorbing portion 27a.
That is, in the stress absorbing portion 27a, a part of one surface 27b of the moisture-proof body 27 is formed in a convex shape, and the other surface 27c of the moisture-proof body 27 is formed in a concave shape in a portion where the surface 27b is formed in a convex shape. It has been done.

The stress absorbing portion 27a can be formed, for example, by subjecting aluminum foil or aluminum alloy foil to press working (embossing) using a press stamping die.
Even in the case of a low moisture permeation and moisture proof film in which a resin film and a film made of an inorganic material are laminated, the stress absorbing portion 27a can be formed by performing press working (embossing) with a press stamping die. .

The height dimension of the stress absorption part 27a can be made larger than the thickness dimension of parts other than the stress absorption part 27a of the moisture-proof body 27. For example, the thickness dimension of the moisture-proof body 27 other than the stress absorbing portion 27a can be about 0.1 mm, and the height dimension of the stress absorbing portion 27a can be about 0.5 mm.
There is no limitation in particular in the width dimension of the stress absorption part 27a. The width dimension of the stress absorbing portion 27a can be appropriately determined according to the magnitude of thermal stress described later, the size of the moisture-proof body 27, and the like.

Here, the thermal expansion coefficient of the alkali-free glass used as the material of the substrate 2a is about 4 ppm / deg at room temperature.
The thermal expansion coefficient of aluminum, which is an example of the material of the moisture-proof body 27, is about 24 ppm / deg at room temperature.
Therefore, when the ambient temperature changes, a thermal stress is generated due to a difference in thermal expansion amount between the materials, and the stress is applied to the structure formed between the moisture-proof body 27 and the substrate 2a.
Specifically, stress is applied to the interface between the moisture-proof body 27 and the bonding layer 8, the interface between the bonding layer 8 and the wall body 9, and the interface between the wall body 9 and the substrate 2a. Furthermore, stress is applied to each element such as the wall body 9 and the bonding layer 8 due to the stress applied to these interfaces.

  Since the stress absorbing portion 27a can be elastically deformed, it can absorb a difference in thermal expansion amount based on a difference in thermal expansion coefficient. Therefore, if the stress absorbing portion 27a is provided, the generated thermal stress can be reduced.

FIG. 7 is a schematic cross-sectional view for illustrating a reflective layer 16 according to another embodiment.
As described above, the base portion 9a and the overhang portion 9b can include a phosphor material.

  When the base portion 9a and the overhang portion 9b include a phosphor material, as shown in FIG. 7, the effective pixel region A can be provided below the base portion 9a and the overhang portion 9b. In this way, the size of the area that needs to be provided around the effective pixel area A can be reduced.

  In this case, the reflective layer 16 can cover the scintillator layer 5, the base portion 9a, and the overhang portion 9b. When the overhang portion 9b includes a phosphor material and the base portion 9a does not include a phosphor material, the reflective layer 16 can cover the scintillator layer 5 and the overhang portion 9b.

FIG. 8 is a schematic cross-sectional view of an X-ray detector 51 according to a comparative example.
As shown in FIG. 8, the X-ray detector 51 according to the comparative example is provided with an array substrate 2, a scintillator layer 5, a reflective layer 6, a moisture-proof body 7, a bonding layer 8, a filling portion 58, and a wall body 59. ing. Although not shown, the X-ray detector 51 is provided with a signal processing unit 3 and an image transmission unit 4 as in the X-ray detector 1.
That is, the X-ray detector 51 according to the comparative example is provided with a filling portion 58 and a wall body 59 instead of the wall body 9 described above.
The filling portion 58 is provided between the side surface of the scintillator layer 5 covered with the reflective layer 6 and the inner surface 59 a of the wall body 9.
The wall body 59 has a frame shape. The wall body 9 is provided outside the scintillator layer 5 in a plan view and inside the region where the wiring pads 2d1 and 2d2 are provided.
The material of the filling portion 58 and the wall body 59 can have a low moisture permeability coefficient. The filling portion 58 and the wall body 59 include, for example, a filler material made of an inorganic material and a resin (for example, an epoxy resin).
The filler material can be formed from, for example, talc.

FIG. 9 is a graph for illustrating a change in moisture permeability under a high temperature and high humidity environment (60 ° C.-90% RH).
In addition, FIG. 9 is the result of having calculated the moisture permeability change from the moisture permeability coefficient at 60 ° C. to 90% RH of the material and the shape and dimensions of the constituent elements.
Further, “200” in FIG. 9 is a case where only the base portion 9a is provided and the overhang portion 9b is not provided. In addition, “200” is a case where the base portion 9a including only the resin is provided without including the filler material made of the inorganic material. When the wall body 9 is only the base portion 9a, the bonding area between the moisture-proof body 7 and the wall body 9 is reduced. Moreover, since the wall body 9 does not contain the filler material which consists of an inorganic material, the moisture permeability coefficient of the wall body 9 becomes large, and the quantity of water vapor (moisture permeability) which permeate | transmits the wall body 9 increases.
“210” in FIG. 9 is the case of the X-ray detector 51 illustrated in FIG. That is, “210” is a case where the wall body 9 is divided into the filling portion 58 and the wall body 59.
“100” in FIG. 9 is the case where the base portion 9a and the overhang portion 9b illustrated in FIG. 2 are provided. Note that “100” is a case where a filler material made of an inorganic material, a base portion 9a containing resin, and an overhang portion 9b are provided.
As can be seen from “100” in FIG. 9, an overhang portion 9 b is provided in the wall body 9 to increase the bonding area between the moisture-proof body 7 and the wall body 9, and a filler material made of an inorganic material is added. If the moisture permeability coefficient of the wall body 9 itself is reduced, it is possible to reduce the moisture permeability as the entire moisture-proof structure.

FIG. 10 is a graph for illustrating a change in resolution characteristics in a high-temperature and high-humidity environment (60 ° C.-90% RH).
Note that “200” in FIG. 10 is a case where only the base portion 9a is provided and the overhang portion 9b is not provided. In addition, “200” is a case where the base portion 9a including only the resin is provided without including the filler material made of the inorganic material.
“210a”, “210b”, and “210c” in FIG. 10 correspond to the case of the X-ray detector 51 illustrated in FIG.
“100” in FIG. 10 is a case where the base 9a and the overhang 9b illustrated in FIG. 2 are provided. Note that “100” is a case where a filler material made of an inorganic material, a base portion 9a containing resin, and an overhang portion 9b are provided.

In addition, the evaluation is based on resolution characteristics that are more sensitive to humidity than luminance.
In this case, it was evaluated how the resolution characteristics obtained by the scintillator layer 5 and the reflective layer 6 deteriorate with the passage of storage time in a high temperature and high humidity environment (60 ° C.-90% RH).
The resolution characteristics were obtained by a method in which a resolution chart was placed on the front side of each sample, X-ray equivalent to RQA-5 was irradiated, and a 2 Lp / mm CTF (Contrast transfer function) was measured from the back side.
As can be seen from “100” in FIG. 10, if the overhang portion 9 b is provided, the degradation of resolution characteristics can be remarkably reduced.

Further, as can be seen from “210” in FIG. 9, the moisture permeability can be suppressed even when the wall body 9 is divided into the filling portion 58 and the wall body 59.
However, if the wall body 9 is divided into the filling part 58 and the wall body 59, the filling part 58 and the wall body 59 will be manufactured separately. In this case, since the wall body 59 needs to maintain a shape, it is formed using a material with high viscosity (for example, about 100 to 400 Pa · sec). This is a necessary condition for maintaining the height as much as possible and suppressing the spread in the lateral direction when a material is applied by a dispenser method or the like. On the other hand, since it is an important point that the filling portion 58 is filled without a gap, the filling portion 58 is formed using a material having a low viscosity (for example, about 0.1 to 10 Pa · sec). However, many low-viscosity materials have a large volumetric shrinkage during curing. For this reason, the adhesion between the filling portion 58 and the wall body 59 may be deteriorated, or gaps or bubbles may be easily generated.
Further, due to other differences in manufacturability such as viscosity and curing method (ultraviolet curing, ultraviolet delayed curing, heat curing, natural curing, etc.), the wall body 9 and the filling portion 58 are often not formed from the same material system. . For example, the base resin of the wall body 9 is an epoxy resin, and the base resin of the filling portion 58 is an acrylic resin. In such a case, the compatibility between the materials is reduced, and the possibility of further worsening the adhesion at the interface increases.
For these reasons, when peeling or a gap occurs at the interface between the filling portion 58 and the wall body 59, water vapor easily enters through the interface.
As a result, as shown by “210a”, “210b”, and “210c” in FIG. 10, variations in resolution characteristics (moisture-proof performance) occur.
Further, when the interface adhesion is insufficient or varies, peeling at the interface between the wall body 9 and the filling portion 58 easily occurs in an environment where heating and cooling are repeated. If peeling occurs, water vapor easily enters from the gap generated by the peeling, and thereafter, the resolution is rapidly lowered.

As described above, if the overhang portion 9b is provided, the moisture-proof bodies 7, 17, and 27 can be joined to the upper surface of the overhang portion 9b. It is not necessary to provide a space for joining 17 and 27.
Therefore, the X-ray detector 1 can be reduced in size and weight.
In this case, if the overhang portion 9b includes a phosphor material, the size of the region that needs to be provided around the effective pixel area A can be further reduced. Further, if the overhang portion 9b and the base portion 9a containing the phosphor material are used, the size of the region that needs to be provided around the effective pixel area A can be minimized.
If the overhang portion 9b is provided, the contact area between the moisture-proof body 7 and the entire wall body 9 can be increased as compared with the case where the wall body 9 does not have the overhang portion. As a result, it is possible to improve the moisture proof performance and to suppress the degradation of resolution characteristics. Further, the large adhesion area between the moisture-proof body 7 and the entire wall body 9 means that the adhesion interface is large even with respect to the stress caused by the difference in thermal expansion between the moisture-proof body 7 and the array substrate 2 when the environmental temperature changes. It becomes difficult to exfoliate by the amount. Therefore, high reliability can be obtained even with respect to temperature changes.
That is, if the overhang portion 9b is provided, it is possible to achieve space saving, moisture proof performance, and improved reliability against environmental temperature changes.

(Second Embodiment)
Next, a method for manufacturing the X-ray detector 1 according to the second embodiment is illustrated.
First, the array substrate 2 is created.
The array substrate 2 can be produced, for example, by sequentially forming the photoelectric conversion unit 2b, the control line 2c1, the data line 2c2, the wiring pad 2d1, the wiring pad 2d2, and the protective layer 2f on the substrate 2a.
The array substrate 2 can be formed using, for example, a semiconductor manufacturing process.

Next, a scintillator layer 5 that converts radiation into fluorescence is formed on the plurality of photoelectric conversion units 2 b provided on the array substrate 2.
The scintillator layer 5 can be formed, for example, by forming a film made of cesium iodide: thallium using a vacuum deposition method or the like. In this case, the thickness dimension of the scintillator layer 5 can be about 600 μm. The column dimension of the columnar crystal can be about 8 μm to 12 μm on the outermost surface.

Next, the reflective layer 6 is formed so as to cover the surface side of the scintillator layer 5 (X-ray incident surface side).
The reflective layer 6 can be formed, for example, by applying a material prepared by mixing a submicron powder made of titanium oxide, a resin, and a solvent onto the scintillator layer 5 and drying it. When the base portion 9a and the overhang portion 9b include a phosphor material, after the base portion 9a and the overhang portion 9b are formed, the reflective layer 6 is formed on the scintillator layer 5, the base portion 9a, and the overhang portion 9b. Form.

Next, a base 9 a that has a frame shape in plan view and surrounds the scintillator layer 5 is formed on the array substrate 2.
The base 9a can be formed, for example, by applying a material prepared by mixing a filler material, a resin, and a solvent around the scintillator layer 5 and curing the material.
Application | coating of material can be performed using a dispenser apparatus etc., for example.
In this case, the base 9a can also be formed by repeating the application of the material and the curing a plurality of times. Further, the material can be mixed with a hygroscopic agent or a phosphor material.

Next, an overhang portion 9 b protruding from the base portion 9 a toward the scintillator layer 5 is formed on the base portion 9 a.
The overhang portion 9b can be formed, for example, by applying a material prepared by mixing a filler material, a resin, and a solvent onto the base portion 9a and curing the material.
Application | coating of material can be performed using a dispenser apparatus etc., for example. Further, the material can be mixed with a hygroscopic agent or a phosphor material.
In this case, the overhang portion 9b can be formed so as to be in close contact with the peripheral end surface 5a1 of the scintillator layer 5.
Further, the overhang portion 9b is provided so that gaps 29a, 19a are provided at least between the overhang portion 9b2 and the peripheral end surface 5a of the scintillator layer 5 and between the overhang portion 9b1 and the array substrate 2. It can also be formed.
In this case, the overhang portion 9b2 and the gap 29a can be formed by appropriately adjusting the viscosity of the material, the amount of application once, and the number of applications.
Moreover, the overhang part 9b1 and the clearance gap 19a can be formed by adjusting the viscosity of a material suitably.

Further, in the step of forming the scintillator layer 5 described above, an inclined portion 5a whose thickness dimension gradually decreases toward the outside of the scintillator layer 5 can be formed on the peripheral portion of the scintillator layer 5 by using a vacuum deposition method. .
In the step of forming the overhang portion 9b, it is possible to form the overhang portion 9b that includes a phosphor material that converts X-rays into fluorescence and a resin, and partially overlaps the inclined portion 5a in plan view.

  Next, the vicinity of the periphery of the moisture-proof bodies 7 and 27 covering the scintillator layer 5 is joined to the upper surface of the overhang portion 9b. Alternatively, the vicinity of the periphery of the moisture-proof body 17 is joined to the upper surface of the overhang portion 9b1. At this time, the bent portion 17a can be fitted into the concave portion provided on the upper surface of the overhang portion 9b1. Further, before the overhang portion 9b1 is hardened, the bent portion 17a can be pressed against the overhang portion 9b1.

For example, an ultraviolet curable adhesive is applied to the upper surface of the overhang portion 9b1, and moisture-proof bodies 7, 17, and 27 are placed on the ultraviolet curable adhesive, and the ultraviolet curable adhesive is irradiated with ultraviolet rays and cured. Thus, the bonding layer 8 is formed, and the moisture-proof bodies 7, 17, and 27 are bonded to the upper surface of the overhang portion 9b1. In this case, the ultraviolet curable adhesive can be a delayed curable adhesive that cures with a delay after ultraviolet irradiation.
If a delayed curable adhesive is used, it is only necessary to place the moisture-proof bodies 7, 17 and 27 on the ultraviolet curable adhesive after the ultraviolet irradiation. In some cases, bonding can be performed.
The adhesive may be a natural curable adhesive or a heat curable adhesive.
Further, in the environment where the pressure is reduced from the atmospheric pressure (for example, about 10 KPa), the vicinity of the peripheral portions of the moisture-proof bodies 7, 17 and 27 can be joined to the upper surface of the overhang portion 9b1.

Next, the array substrate 2 and the signal processing unit 3 are electrically connected via the flexible printed boards 2e1 and 2e2.
Further, the signal processing unit 3 and the image transmission unit 4 are electrically connected through the wiring 4a.
In addition, circuit components and the like are mounted as appropriate.

Next, the array substrate 2, the signal processing unit 3, the image transmission unit 4, and the like are stored in a housing (not shown).
Then, as necessary, an electrical test, an X-ray image test, and the like are performed to check whether the photoelectric conversion element 2b1 is abnormal or not.
The X-ray detector 1 can be manufactured as described above.
In addition, in order to confirm the moisture-proof reliability of the product and the reliability against changes in the temperature environment, a high-temperature and high-humidity test, a cooling / heating cycle test, and the like can also be performed.

  As mentioned above, although several embodiment of this invention was illustrated, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, changes, and the like can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and equivalents thereof. Further, the above-described embodiments can be implemented in combination with each other.

  1 X-ray detector, 2 array substrate, 2a substrate, 2b photoelectric conversion unit, 3 signal processing unit, 4 image transmission unit, 5 scintillator layer, 5a inclined portion, 5a1 circumferential end surface, 6 reflective layer, 7 moisture barrier, 9 wall Body, 9a base, 9b overhang, 9b1 overhang, 9b2 overhang, 19 wall, 19a gap, 29 wall, 29a gap

Claims (18)

An array substrate having a plurality of photoelectric conversion elements;
A scintillator layer that is provided on the plurality of photoelectric conversion elements and converts radiation into fluorescence;
A base provided on the array substrate, having a frame shape in plan view and surrounding the scintillator layer;
An overhang portion provided integrally with the base portion on the base portion and projecting from the base portion toward the scintillator layer;
A moisture-proof body that covers an upper portion of the scintillator layer and a peripheral edge portion is bonded to at least the upper surface of the overhang portion;
Radiation detector equipped with. The scintillator layer has an inclined portion that gradually decreases in the peripheral portion toward the outer side of the scintillator layer,
The radiation detector according to claim 1, wherein at least a part of the overhang portion overlaps the inclined portion in plan view.   The radiation detector according to claim 1, wherein the overhang portion is in close contact with a peripheral end surface of the scintillator layer.   The radiation detection according to claim 1, wherein a gap is provided between at least one of the overhang portion and the peripheral end surface of the scintillator layer and between the overhang portion and the array substrate. vessel.   The base and the overhang part include at least one of a filler material containing an inorganic material, a hygroscopic agent, and a first phosphor material that converts radiation into fluorescence, and a resin. The radiation detector as described in any one. The scintillator layer includes a second phosphor material that converts radiation into fluorescence;
The radiation detector according to claim 5, wherein the second phosphor material is different from the first phosphor material. The scintillator layer includes a second phosphor material that converts radiation into fluorescence;
The radiation detector according to claim 5, wherein the second phosphor material is the same as the first phosphor material.   The inorganic material is any one of a silicate mineral, silicon oxide, aluminum oxide, silicon nitride, aluminum nitride, silicon carbide, aluminum carbide, a composite compound containing at least silicon and oxygen, aluminum, and a metal having a specific gravity smaller than that of aluminum. The radiation detector according to claim 4.   The radiation detector according to any one of claims 1 to 8, wherein the moisture-proof body has a bent portion protruding toward the array substrate side in the vicinity of the periphery.   The said moisture-proof body is a radiation detector as described in any one of Claims 1-9 which has an embossed stress absorption part.   The radiation detector according to any one of claims 1 to 10, wherein the moisture-proof body includes aluminum or an aluminum alloy. Forming a scintillator layer for converting radiation into fluorescence on the plurality of photoelectric conversion elements provided on the array substrate;
On the array substrate, forming a base that surrounds the scintillator layer in a frame shape in plan view;
Forming an overhang portion projecting from the base portion toward the scintillator layer on the base portion;
Bonding the vicinity of the periphery of the moisture-proof body covering the upper side of the scintillator layer to at least the upper surface of the overhang portion;
A method of manufacturing a radiation detector comprising: In the step of forming the scintillator layer, on the peripheral portion of the scintillator layer, an inclined portion that gradually decreases as the thickness dimension goes to the outside of the scintillator layer,
The method of manufacturing a radiation detector according to claim 12, wherein in the step of forming the overhang portion, the overhang portion is formed so that at least a part thereof overlaps the inclined portion in plan view.   The method of manufacturing a radiation detector according to claim 12 or 13, wherein, in the step of forming the overhang portion, the overhang portion is formed so as to be in close contact with a peripheral end surface of the scintillator layer.   In the step of forming the overhang portion, the gap is provided between at least one of the overhang portion and the peripheral end surface of the scintillator layer and between the overhang portion and the array substrate. The manufacturing method of the radiation detector of Claim 12 or 13 in which an overhang part is formed.   The radiation detector according to any one of claims 13 to 15, wherein in the step of forming the overhang portion, the overhang portion including a first phosphor material that converts radiation into fluorescence and a resin is formed. Manufacturing method.   The method further comprises the step of joining at least the vicinity of the periphery of the moisture-proof body to at least the upper surface of the overhang using any one of a delayed curable adhesive, a natural curable adhesive, and a heat curable adhesive. The manufacturing method of the radiation detector as described in any one of -16.   In the step of joining the vicinity of the periphery of the moisture-proof body to at least the top surface of the overhang portion, the vicinity of the periphery of the moisture-proof body is joined to at least the top surface of the overhang portion in an environment reduced in pressure from atmospheric pressure. Item 18. A method for manufacturing a radiation detector according to Item 17.

Images