JP2007103967A - Two-dimensional image detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a two-dimensional image detector possessing high reliability as a device by preventing device performance degradation caused by the deterioration such as the decay of the insulating film exposed at the peripheral portions of a pixel region. <P>SOLUTION: The two-dimensional image detector comprises a photoconductive film 2 having photoconductivity and arranged on an active-matrix substrate 1 and a common electrode 3 further arranged on the photoconductive film 2 in the disposed area of a second insulating protection film 7. The second insulating protection film 7 is formed in an area wider than that of the photoconductive film 2. The device is also provided with a third insulating protection film 32 which covers at least an end of the common electrode 3, exposed surface of the photoconductive film 2, and exposed portion of the second insulating protection film 7. The third insulating protection film 32 is composed of a material through which X-rays penetrate, and the two-dimensional image detector detects an X-ray image. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a two-dimensional image detector capable of detecting an image of radiation such as X-rays or light rays such as visible light and infrared rays.

  Conventionally, as a two-dimensional image detector capable of detecting an image of radiation such as X-rays, or light rays such as visible light and infrared light, the charge generated in the photosensitive semiconductor layer is used in a conventional liquid crystal display device. A device that collects, reads, and images each pixel on an active matrix substrate is known. Among them, the pixel electrode is superimposed on the address line (electrode wiring) and TFT element of the active matrix substrate through an insulating layer for the purpose of obtaining the effect of increasing the fill factor (aperture ratio) per pixel. There is an example in which such a structure (roof-type structure) is adopted.

  For example, the literature “W.den Boer, et al.,“ Similarities between TFT Arrays for D-irect-Conversion X-ray Sensors and High-Aperture AMLCDs ”, SID 98 DIGEST, PP.371-374, 1998”, “USP5 780, 871 "and the like describe a specific structure.

  FIG. 9 is a cross-sectional view schematically showing a configuration per pixel of a two-dimensional image detector employing the roof-type active matrix substrate.

  As shown in the figure, a two-dimensional image detection is performed by laminating a photoconductive film 102 on an active matrix substrate 101 having a roof structure and further laminating a common electrode 103 on the photoconductive film 102. The basic structure of the vessel is formed.

  In the active matrix substrate 101 having the roof type structure, a thin film transistor (TFT) 105 and a charge storage capacitor (Cs) 106 as switching elements are formed on a glass substrate 104. The TFT 105 and the charge storage capacitor ( The pixel electrode 107 covers the upper part of the Cs) 106.

The TFT 105 includes a gate electrode 108, a gate insulating film 109, an a-Si film (i layer) 110, an a-Si film (n ⁺ layer) 111, a source electrode 112, and a drain electrode 113. The charge storage capacitor (Cs) 106 is formed by a storage capacitor electrode (Cs electrode) 114, a gate insulating film 109, and a drain electrode 113 that also functions as the other storage capacitor electrode.

  The electrode wiring (the gate electrode 108 and the source electrode 112), the TFT 105, the charge storage capacitor (Cs) 106, and the pixel electrode 107 are electrically insulated by an insulating layer 115 existing therebetween. Further, the pixel electrode 107 and the drain electrode 113 are in a conductive state through a contact hole 116 provided in the insulating layer 115.

  The photoconductive film 102 is made of a semiconductor material that generates charges (electrons-holes) when irradiated with radiation such as X-rays or light rays such as visible light.

  Next, the operation principle of the two-dimensional image detector will be described.

  When a voltage is applied between the common electrode 103 and the storage capacitor electrode (Cs electrode) 114, when the photoconductive film 102 is irradiated with radiation such as X-rays or light such as visible light, the photoconductive Electric charges (electron-holes) are generated inside the film 102. The generated charges move to the positive and negative electrodes according to the direction of the applied voltage, and the charges are stored in the charge storage capacitor (Cs) 106. The charge stored in the charge storage capacitor (Cs) 106 can be taken out from the source electrode 112 by opening the TFT 105 with an input signal to the gate electrode 108.

  Since the electrode wiring (the gate electrode 108 and the source electrode 112), the TFT 105, the charge storage capacitor (Cs) 106, and the like are provided in an XY matrix, the signals input to the gate electrode 108 are scanned line-sequentially. Image information can be obtained two-dimensionally.

In the two-dimensional image detector using the active matrix substrate having the roof type structure as described above, in order to insulate the pixel electrode from the address line (electrode wiring), the insulation shown in FIG. An insulating layer such as the film 115 is provided. Materials that can be used as the insulating layer include SiO _x , SiN _x , Al ₂ O ₃ , polyimide, acrylic resin, and the like, but superiority and inferiority are used as the materials used for the following reasons.

First, the resin can be formed into a film by a technique such as spin coating or film lamination. On the other hand, since SiO _x , SiN _{x and the} like are formed by CVD (Chemical Vapor Deposition) deposition, the manufacturing cost is higher than that of resins. Furthermore, if it is a resin, it is possible to form the film surface portion flat by a method such as spin coating. However, when SiO _x , SiN _x or the like is formed by CVD deposition, a lower layer is formed on the formed film. Since unevenness is reflected, a problem arises in the flatness of the surface of the formed film. In the two-dimensional image detector, the irregularities on the surface of the insulating layer are reflected in the photoconductive layer formed on the active matrix substrate, leading to a decrease in detection performance. Accordingly, it is appropriate to use resins in order to form the surface of the insulating layer flat.

  Next, in the two-dimensional image detector, the parasitic capacitance generated in the portion where the address line (electrode wiring) and the pixel electrode are overlapped is a main cause of signal noise generation. It is necessary to reduce the parasitic capacitance. Therefore, it is desirable that the insulating layer is as thick as possible. However, when the insulating layer is formed by CVD deposition, it is difficult to increase the thickness to 1 μm or more.

  However, if it is resin, since spin coating can be used, it is relatively easy to increase the film thickness. Furthermore, since various types of resins generally have a low dielectric constant, it is possible to reduce parasitic capacitance.

  In addition, it is necessary to form a contact hole for connecting the pixel electrode and the drain electrode in the insulating layer. The contact hole is formed by a photolithographic technique. However, in the case of a material having photosensitivity such as an acrylic resin, a process such as resist coating and etching is not required when forming the contact hole. Compared to the case, it contributes to shortening of the process.

For the reasons described above, the material used for the insulating layer is preferably a resin such as acrylic having a low dielectric constant and photosensitivity, and the method used is preferably film formation by spin coating. Moreover, it is desirable that the material used for the insulating layer has a low dielectric constant in order to reduce parasitic capacitance.
Japanese Patent Laid-Open No. 11-068078 (published on March 9, 1999) JP 10-284710 A (published October 23, 1998) JP 06-029431 A (published February 4, 1994) Japanese Patent Laid-Open No. 06-021413 (published January 28, 1994) Japanese Utility Model Publication No. 63-153557 (released on October 7, 1988) Japanese Utility Model Publication No. 61-027350 (published February 18, 1986) JP-A-64-021975 (released on January 25, 1988) JP-A-11-087683 (published on March 30, 1999)

  However, when a roof-type active matrix substrate using an insulating layer made of a resin such as acrylic as described above is employed for the conventional two-dimensional image detector, the following problems arise.

  That is, in the case of the active matrix substrate having the roof type structure as described above, if the insulating layer made of resin is exposed at the periphery of the pixel region, the material deterioration of the insulating layer is caused as a device. There is a risk that reliability will be greatly affected. Specifically, it is moisture in the air that is particularly concerned as a factor affecting reliability. Resins such as acrylic are generally vulnerable to moisture, so when such resins are used, the insulating layer peels off from the exposed portion of the insulating layer due to moisture in the air, and the like is altered. The phenomenon that the deterioration of the material progresses with time is inevitable. In addition, resins such as acrylic also have a problem that deterioration such as polymerization and decomposition is likely to occur due to radiation such as X-rays.

  The present invention has been made in view of the above problems, and in a two-dimensional image detector in which a photoconductive semiconductor layer is stacked on an active matrix substrate having a roof structure, insulation exposed at the periphery of the pixel region is provided. It is an object of the present invention to provide a two-dimensional image detector having high reliability as a device by preventing degradation of device performance caused by degradation of layers and the like.

  In order to solve the above-described problems, the two-dimensional image detector of the present invention provides electrode wiring arranged in a grid, switching elements provided for each grid point, and the electrode wiring via the switching elements. On the charge storage capacitor to be connected, an active matrix substrate in which a pixel electrode is disposed via an insulating layer, a photoconductive semiconductor layer provided on the active matrix substrate, and the semiconductor layer, An electrode layer further provided in the arrangement region of the insulating layer, and the insulating layer is formed in a region wider than the semiconductor layer, and at least an end portion of the electrode layer and an exposed surface of the semiconductor layer, And a protective film made of a material that transmits X-rays, covering the exposed portion of the insulating layer, and detecting an X-ray image.

  In the above structure, it is desirable that the protective film covers the entire electrode layer, the exposed surface of the semiconductor layer, and the exposed portion of the insulating layer.

  In the above configuration, the protective film is preferably an insulating film that prevents creeping discharge.

  As a result, it is possible to provide a two-dimensional image detector having high reliability as a device by preventing deterioration in device performance caused by deterioration such as decay of the insulating layer exposed in the periphery of the pixel region.

  Furthermore, in the two-dimensional image detector of the present invention, in all the above-described configurations, it is desirable that the insulating layer is made of a resin.

  According to said structure, by using resin with respect to an insulating layer, this insulating layer can be formed by spin coating or film lamination, for example. Therefore, the film surface of the insulating layer can be formed flat, and further, the thickening of the insulating layer can be easily realized. In addition, since various kinds of resins generally have a low dielectric constant, the insulating layer can be formed with a low dielectric constant.

  Accordingly, it is possible to realize a two-dimensional image detector that suppresses a decrease in detection performance, reduces parasitic capacitance, and suppresses the generation of signal noise at a low cost.

  As described above, the two-dimensional image detector of the present invention includes electrode wirings arranged in a grid, switching elements provided for each grid point, and electric charges connected to the electrode wirings through the switching elements. An active matrix substrate in which a pixel electrode is disposed on the storage capacitor via an insulating layer, a photoconductive semiconductor layer provided on the active matrix substrate, and the insulating layer on the semiconductor layer. An electrode layer further provided in the arrangement region, and the insulating layer is formed in a region wider than the semiconductor layer. At least an end of the electrode layer, an exposed surface of the semiconductor layer, and the insulating layer An X-ray image is detected by providing a protective film that covers the exposed portion and is made of a material that transmits X-rays.

  Therefore, there is an effect that it is possible to suppress material deterioration due to exposure of the exposed portion of the insulating layer to the external atmosphere and material deterioration due to radiation exposure when detecting radiation such as X-rays.

[Reference form]
The reference embodiment of the present invention will be described below with reference to FIGS.

  The two-dimensional image detector according to this reference embodiment is an X-ray sensitive two-dimensional image detector.

  FIG. 1 is a cross-sectional view showing a basic configuration of a two-dimensional image detector in the present embodiment. FIG. 2 is a cross-sectional view showing a configuration per pixel of the two-dimensional image detector. FIG. 3 is an explanatory diagram schematically showing the positional relationship between the stacked films described below in the two-dimensional image detector.

  As shown in FIG. 1, the two-dimensional image detector according to this embodiment has a photoconductive film (semiconductor layer) 2 and a common electrode (electrode layer) 3 formed on an active matrix substrate 1. The basic part is configured. The active matrix substrate 1 includes a gate insulating film formed on almost the entire surface of a glass substrate 4 which is a support substrate provided with a gate electrode (electrode wiring) and a storage capacitor electrode (Cs electrode) (not shown) described later. 5, a first insulating protective film 6 formed on the gate insulating film 5, a second insulating protective film (insulating layer) 7 formed on the first insulating protective film 6, and the second A plurality of pixel electrodes 8 are provided as a pixel arrangement layer formed in a matrix on the insulating protective film 7.

  The photoconductive film 2 is formed on almost the entire surface of the active matrix substrate 1, and an end portion of the second insulating protective film 7, that is, a pixel region (display region) in the second insulating protective film 7. The surrounding area is completely covered.

  The common electrode 3 is formed on almost the entire surface of the photoconductive film 2 and in a region narrower than a region where the second insulating protective film 7 is formed. That is, the common electrode 3 is formed in the arrangement region of the second insulating protective film 7.

  In the two-dimensional image detector according to this embodiment, the pixel electrode 8 is a square having a side of 130 μm and a pixel pitch of 150 μm. The entire pixel area (display area) is a square having a side of about 430 mm.

  Below, based on FIG. 2, the structure of the two-dimensional image detector in this reference form is demonstrated in detail.

  An XY matrix electrode wiring (gate electrode 9 and source electrode 10), a thin film transistor (hereinafter referred to as TFT (Thin Film Transistor)) 11, a charge storage capacitor (Cs) 12 and the like are provided on the glass substrate 4. It has been.

  Specifically, an alkali-free glass substrate (for example, # 7059 or # 1737 manufactured by Corning) is used as the glass substrate 4. On the glass substrate 4, a gate electrode 9 and a storage capacitor electrode (Cs electrode) 13 made of a metal film such as Ta (tantalum) or A1 (aluminum) are disposed.

A gate insulating film 5 made of SiN _x or SiO _x is provided on almost the entire surface of the glass substrate 4 so as to cover the gate electrode 9 and the storage capacitor electrode (Cs electrode) 13. The gate insulating film 5 also functions as a component of the charge storage capacitor (Cs) 12. As the gate insulating film 5, not only SiN _x and SiO _x but also an anodized film obtained by anodizing the gate electrode 9 and the charge storage capacitor electrode (Cs electrode) 13 may be used in combination.

An a-Si film for making contact between the a-Si film (i layer) 14 serving as a channel portion of the TFT 11 and the source electrode 10 and the drain electrode 16 via the gate insulating film 5 on the gate electrode 9. (N ⁺ layer) 15 is provided.

On the a-Si film (n ⁺ layer) 15, a source electrode 10 and a drain electrode 16 (also serving as a Cs electrode) made of a metal film such as Ta or Al are provided.

As described above, the first insulating protective film 6 made of SiN _x is provided so as to cover almost the entire surface of the glass substrate 4 on which the TFT 11 and the charge storage capacitor 12 are formed. Further, a second insulating protective film 7 having a thickness of about 3 μm is provided so as to cover almost the entire surface of the first insulating protective film 6. For the second insulating protective film 7, a photosensitive organic insulating film, for example, an acrylic resin is used.

  A pixel electrode 8 made of ITO (Indium Tin Oxide) is provided on the second insulating protective film 7. A contact hole 17 is provided in the second insulating protective film 7, and the pixel electrode 8 and the drain electrode 16 are short-circuited through the contact hole 17.

  Here, as the TFT element, a TFT having an inverted stagger structure using a-Si is used. However, the TFT element is not limited to this, and p-Si may be used, or a staggered structure may be used. .

  Next, a photoconductive film 2 made of a-Se and having a film thickness of about 0.5 to 1 mm is provided on the pixel region of the active matrix substrate 1 manufactured as described above. The photoconductive film 2 formed of a-Se is formed so as to cover the second insulating protective film 7 exposed at the end of the pixel region in addition to the entire pixel region.

  Further, a common electrode 3 made of Au (gold) is disposed on the photoconductive film 2 so as to cover the pixel region 18 (see FIG. 3). The common electrode 3 is formed in a region larger than the pixel region 18 and smaller than a region where the second insulating protective film 7 is formed.

  In the two-dimensional image detector according to the present embodiment configured as described above, the second insulating protective film 7 is provided up to a region outside the pixel region 18 as shown in FIG. In the present embodiment, the second insulating protective film 7 is provided up to a region about 5 mm outside the pixel region 18. In addition, since the photoconductive film 2 is formed to a region further 1 to 10 mm outside the end of the second insulating protective film 7, the exposed portion of the second insulating protective film 7 is the light beam. The conductive film 2 is completely covered.

  Next, the manufacturing method of the two-dimensional image detector will be described in detail.

  The active matrix substrate 1 constituting the two-dimensional image detector according to the present embodiment can be formed by the same process as the active matrix substrate formed in the process of manufacturing the liquid crystal display device.

  In the first step, a metal film such as Ta or Al is formed on the glass substrate 4 which is an alkali-free glass substrate by sputtering deposition to a thickness of about 3000 mm, and then patterned into a desired shape to obtain a gate electrode. 9 is formed. At the same time, a storage capacitor electrode (Cs electrode) 13 is also formed.

In the second step, SiN _x or SiO _x is deposited to a thickness of about 3500 mm by the CVD method to form the gate insulating film 5.

In the third step, an a-Si film (i layer) and an a-Si film (n ⁺ layer) are formed by CVD so that the thicknesses are about 1000 mm and about 400 mm, respectively, and the desired shape is obtained. Then, an a-Si film (i layer) 14 and an a-Si film (n ⁺ layer) 15 are formed on the gate electrode 9.

  In the fourth step, a metal film such as Ta or Al is formed by sputtering deposition to a thickness of about 3000 mm, and then patterned into a desired shape to form the source electrode 10 and the drain electrode 16.

In the fifth step, SiN _x is deposited to a thickness of about 3000 mm by the CVD method, and the SiN _x film is removed only at a predetermined portion above the drain electrode 16 where the contact hole 17 is formed in the subsequent step. A first insulating protective film 6 is formed.

  In the sixth step, an organic insulating film such as a photosensitive acrylic resin is formed to form the second insulating protective film 7, and the second insulating protective film 7 is formed by patterning using a photolithography technique. A contact hole 17 is formed at a predetermined location.

  In the seventh step, ITO is deposited to a thickness of about 2000 mm by sputtering deposition, and then patterned into a desired shape to form the pixel electrode 8. At this time, the pixel electrode 8 and the drain electrode 16 are short-circuited through the contact hole 17 provided in the second insulating protective film 7.

  On the active matrix substrate 1 completed through the above steps, an a-Se film is formed to a thickness of about 0.5 to 1 mm by using a vacuum evaporation method, and the photoconductive film 2 is formed. At this time, the photoconductive film 2 is formed in a region wider than the formation region of the second insulating protective film 7 so as to completely cover the end portion of the second insulating protective film 7. The temperature at this time is room temperature.

  Further, a common electrode 3 is formed on the photoconductive film 2 in a region narrower than the region where the second insulating protective film 7 is formed by depositing Au to a thickness of about 2000 mm using a vacuum deposition method. Form.

  The basic components of the two-dimensional image detector are formed by the processes as described above.

  As described above, in the two-dimensional image detector according to the present embodiment, a portion of the second insulating protective film 7 made of acrylic resin that is exposed in the peripheral part of the pixel region 18 is a photoconductive film made of a-Se. The structure is completely covered with 2. Therefore, since the second insulating protective film 7 exposed in the peripheral portion of the pixel region 18 as described above does not structurally contact with the external atmosphere, the acrylic resin due to the influence of moisture or the like contained in the external atmosphere No film peeling or material deterioration occurs. In addition, since the second insulating protective film 7 exposed in the peripheral portion of the pixel region 18 as described above is not directly exposed to X-rays, deterioration of the resin material due to exposure is suppressed.

  In the two-dimensional image detector according to the present embodiment, a film made of a-Se is formed as the photoconductive film 2 with a thickness of about 0.5 to 1.0 mm, and the common electrode 3 at this time is formed. The voltage applied to is a high voltage of several kV to several tens of kV. Here, by making the formation region of the common electrode 3 smaller than the formation region of the second insulating protective film 7, the common electrode 3 does not exist in the absence region of the second insulating protective film 7. Therefore, a high voltage is not applied to the photoconductive film 2 in the region where the second insulating protective film 7 is absent.

  Therefore, a high voltage is not directly applied to the first insulating protective film 6 provided on the gate electrode 9, the source electrode 10, the charge storage capacitor (Cs) 12, and the like. It is possible to prevent dielectric breakdown, that is, breakdown of the first insulating protective film 6. In addition, it is possible to suppress the generation of parasitic capacitance of the first insulating protective film 6, and it is also possible to obtain the effect of suppressing the generation of signal noise and improving the reliability of the device.

  As a comparative example, FIG. 4 shows a two-dimensional image detector having a configuration in which an end of an acrylic resin as the second insulating protective film 7 is exposed. In this case, there arises a problem that the exposed portion 19 of the second insulating protective film 7 made of acrylic resin is likely to be deteriorated by contact with the outside air.

  In the present embodiment, the acrylic resin having photosensitivity is used for the second insulating protective film 7, but other resins may be used regardless of the photosensitivity. Moreover, you may use insulating materials other than resin.

[Embodiment 1]
The embodiment of the present invention will be described with reference to FIGS. 5 and 6 as follows. For convenience of explanation, the same reference numerals are given to the same components as those described in the reference embodiment, and the description thereof is omitted.

  The basic configuration and manufacturing method of the two-dimensional image detector according to the present embodiment are substantially the same as those of the reference embodiment and the two-dimensional image detector according to the first embodiment. However, the two-dimensional image detector according to the present embodiment does not employ a structure that covers the exposed portion of the second insulating protective film with a photoconductive film.

  FIG. 5 is a cross-sectional view schematically showing a basic configuration of the two-dimensional image detector according to the present embodiment. As shown in the figure, the two-dimensional image detector according to the present embodiment includes a photoconductive film 2 and a common electrode 3 formed on an active matrix substrate 1, thereby constituting a basic part as a device. Yes.

  The second insulating protective film 7 is formed in a region wider than the photoconductive film 2, and an end portion thereof is an exposed portion 31 that is not covered with the photoconductive film 2. A third insulating protective film 32 made of an epoxy resin is provided so as to cover the exposed portion 31. The third insulating protective film 32 may be formed with a margin to the outside of the end portion of the exposed portion 31 of the second insulating protective film 7 in consideration of its own material deterioration. preferable. Therefore, in the present embodiment, the third insulating protective film 32 is disposed so as to cover about 1 cm outside the end of the exposed portion 31 of the second insulating protective film 7.

  As described above, in the two-dimensional image detector according to the present embodiment, the exposed portion 31 of the second insulating protective film 7 made of acrylic resin is completely covered by the third insulating protective film 32 made of epoxy resin. Covered. Accordingly, since the exposed portion 31 of the second insulating protective film 7 is structurally not in contact with the external atmosphere, film peeling of the second insulating protective film 7 due to the influence of moisture or the like contained in the external atmosphere is prevented. The occurrence of material deterioration can be suppressed. For the same reason, since the second insulating protective film 7 made of acrylic resin is not directly exposed to X-rays, it is possible to suppress deterioration of the resin material due to exposure.

  In the present embodiment, an epoxy resin is used as the third insulating protective film 32. However, another material having an insulating property equivalent to that of the epoxy resin, for example, polyimide may be used.

  Further, the third insulating protective film 32 only needs to completely cover the exposed portion 31 of the second insulating protective film 7, and there is no particular limitation on the shape and formation region thereof. For example, as shown in FIG. 6, the third insulating protective film 32 is disposed on the surface of the device so as to cover the entire exposed portion 31 of the common electrode 3, the photoconductive film 2, and the second insulator film 7. It is also possible to do. Thus, by covering the surface of the device with the third insulating protective film 32, in addition to protecting the exposed portion 31 of the second insulating protective film 7, it is also possible to prevent condensation on the surface of the device.

  Further, during the operation of the device, a high voltage of several kV to several tens of kV is applied to the common electrode 3, but creeping discharge can be prevented by covering the surface of the device with the third insulating protective film 32. The effect is also obtained.

  In the case of such a configuration, since the third insulating protective film 32 covers the image detection region, that is, the formation region of the common electrode 3, the third insulating protective film 32 has a property of shielding X-rays. It cannot be formed using the material which has. However, the above-described resins such as epoxy resin, silicon resin, and polyimide can be used because they sufficiently transmit X-rays as the material of the third insulating protective film 32 in the present embodiment.

[Embodiment 2]
The embodiment of the present invention will be described with reference to FIGS. 7 and 8 as follows. For convenience of explanation, the same reference numerals are given to the same components as those described in the first embodiment, and the description thereof is omitted.

  The basic configuration and manufacturing method of the two-dimensional image detector according to the present embodiment are substantially the same as those of the reference embodiment and the two-dimensional image detector according to the first embodiment. However, the two-dimensional image detector according to the present embodiment does not employ a structure that covers the exposed portion of the second insulating protective film with a photoconductive film.

FIG. 7 is a cross-sectional view schematically showing a basic configuration of the two-dimensional image detector according to the present embodiment. As shown in the figure, the basic component of a two-dimensional image detector configured by forming a photoconductive film 2 made of a-Se and a common electrode 3 made of Au on an active matrix substrate 1 is a container ( The shielding member 20 is inserted into the container 20, and the atmosphere inside the container 20 is replaced with N ₂ (nitrogen) gas. The container 20 is made of a material having excellent permeability to X-rays, such as carbon. After the basic component of the two-dimensional image detector is inserted into the container 20, the internal atmosphere of the container 20 is continuously replaced with a certain amount of N ₂ gas, thereby detecting the two-dimensional image according to the present embodiment. A vessel is formed.

  With the configuration as described above, the exposed portion 21 of the second insulating protective film 7 formed of acrylic resin is shielded from the external atmosphere by the container 20 and therefore comes into contact with the external atmosphere containing moisture. There is no. Therefore, it is possible to prevent the acrylic resin film from peeling and the material deterioration due to moisture.

In the present embodiment, the exposed portion 21 of the second insulating protective film 7 is not covered with the photoconductive film 2, but the exposed portion of the second insulating protective film is the same as in the reference embodiment and the first embodiment. 21 may be covered. In addition to N ₂ , an inert gas such as Ar (argon) or a dry gas can be used as the replacement gas.

  Also, the second insulating protective film 7 can be shielded from the external atmosphere by reducing the internal atmosphere of the container 20. Further, the degree of decompression is not uniform and may be set as appropriate in consideration of the load on the apparatus.

  In consideration of the fact that the container 20 is made of a material excellent in X-ray permeability, as shown in FIG. 8, it is located outside the image detection area, that is, above the area where the common electrode 3 does not exist, and It is also possible to provide an X-ray shielding member 22 on the outer surface of the container 20. With such a configuration, the exposed portion 21 of the second insulating protective film 7 is not directly exposed to X-rays, so that material deterioration such as polymerization or decomposition of the organic insulating film in the exposed portion 21 portion is further reduced. It becomes possible to suppress.

  For the X-ray shielding member 22, a material having a high radiation shielding effect such as Ta, Pb (lead), W (tungsten), Ba (barium) is appropriately used.

  Here, the characteristic parts of the two-dimensional image detector according to the present invention are summarized as follows.

  A two-dimensional image detector according to the present invention includes electrode wirings arranged in a grid pattern on a support substrate, a plurality of switching elements provided for each grid point, and connected to the electrode wirings via the switching elements. Active having a pixel array layer comprising a charge storage capacitor, an insulating layer provided on the electrode wiring, the switching element and the charge storage capacitor, and a pixel electrode provided for each lattice on the insulating layer In the two-dimensional image detector, comprising: a matrix substrate; a semiconductor layer having photoconductivity formed on substantially the entire surface of the pixel array layer; and an electrode layer formed on substantially the entire surface of the semiconductor layer. The layer is formed in a region wider than the insulating layer, and an end portion of the insulating layer is covered with the semiconductor layer.

  Furthermore, in the above-described configuration, the two-dimensional image detector according to the present invention may be configured such that the electrode layer is formed in a region equal to or narrower than the insulating layer.

  Further, the two-dimensional image detector according to the present invention has a configuration in which the end of the insulating layer is covered with a protective film such as a resin instead of the configuration in which the end of the insulating layer is covered with the photoconductive layer. Also good.

  Further, the two-dimensional image detector according to the present invention includes an electrode wiring arranged in a grid pattern on a support substrate, a plurality of switching elements provided for each grid point, and the electrode wiring via the switching elements. A pixel array layer comprising: a charge storage capacitor connected to each other; an insulating layer provided on the electrode wiring, the switching element, and the charge storage capacitor; and a pixel electrode provided for each lattice on the insulating layer. In a two-dimensional image detector comprising: an active matrix substrate having: a photoconductive semiconductor layer formed on substantially the entire surface of the pixel array layer; and an electrode layer formed on substantially the entire surface of the semiconductor layer. A configuration part of the two-dimensional image detector including the active matrix substrate, the semiconductor layer, and the electrode layer may be shielded from the external atmosphere.

  Furthermore, in the above-described configuration, the two-dimensional image detector according to the present invention includes a component part of the two-dimensional image detector including the active matrix substrate, the semiconductor layer, and the electrode layer in an inert gas atmosphere and a dry gas atmosphere. It can also be set as the structure shielded from external atmosphere by being maintained in either the bottom or the pressure-reduced atmosphere.

It is sectional drawing of the edge part periphery of this two-dimensional image detector which shows the structure of the two-dimensional image detector which concerns on the reference form of this invention roughly. It is sectional drawing which shows the structure per pixel in the said two-dimensional image detector. In the said two-dimensional image detector, it is explanatory drawing which shows roughly the positional relationship of each laminated | stacked film | membrane. It is sectional drawing which shows roughly the structure of the two-dimensional image detector used as a comparative example with respect to the said two-dimensional image detector. It is sectional drawing of the edge part periphery of this two-dimensional image detector which shows roughly the structure of the two-dimensional image detector which concerns on one embodiment of this invention. It is sectional drawing of the edge part periphery of this two-dimensional image detector which shows roughly the structure of the two-dimensional image detector which is an improvement example of the said two-dimensional image detector. It is sectional drawing of the edge part periphery of this two-dimensional image detector which shows roughly the structure of the two-dimensional image detector which concerns on other embodiment of this invention. It is sectional drawing of the edge part periphery of this two-dimensional image detector which shows roughly the structure of the two-dimensional image detector which is an improvement example of the said two-dimensional image detector. It is sectional drawing which shows schematically the structure of the conventional two-dimensional image detector as which the roof type | mold structure is employ | adopted.

Explanation of symbols

1 Active matrix substrate 2 Photoconductive film (semiconductor layer)
3 Common electrode (electrode layer)
7 Second insulating protective film (insulating layer)
8 Pixel electrode 9 Gate electrode (electrode wiring)
10 Source electrode (electrode wiring)
11 Thin film transistor (TFT) (switching element)
12 Charge storage capacity 20 Container (shielding member)
21 Exposed part (end part)
22 X-ray shielding member 31 Exposed part (end part)
32 3rd insulation protective film (protective film)

Claims (4)

Pixel electrodes are arranged via an insulating layer on electrode wirings arranged in a grid, switching elements provided for each grid point, and charge storage capacitors connected to the electrode wirings via the switching elements. An active matrix substrate,
A photoconductive semiconductor layer provided on the active matrix substrate;
On the semiconductor layer, with an electrode layer further provided in the arrangement region of the insulating layer,
The insulating layer is formed in a wider area than the semiconductor layer,
An X-ray image is detected, comprising a protective film made of a material that transmits X-rays and covering at least an end portion of the electrode layer, an exposed surface of the semiconductor layer, and an exposed portion of the insulating layer. Two-dimensional image detector.   The two-dimensional image detector according to claim 1, wherein the protective film covers all of the electrode layer, an exposed surface of the semiconductor layer, and an exposed portion of the insulating layer.   The two-dimensional image detector according to claim 1, wherein the protective film is an insulating film that prevents creeping discharge.   4. The two-dimensional image detector according to claim 1, wherein the insulating layer is made of a resin.

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