JP2011108890A - Radiation detecting element - Google Patents

Abstract

The present invention provides a radiation detection element that protects a cut portion for separating a defective pixel while separating and repairing the defective pixel.
At least one of a scanning wiring 101 and a signal wiring 3 connected to a TFT switch 4 of a defective pixel 7A is cut at a portion outside a detection region S and covered with a protection part 32.
[Selection] Figure 6

Description

  The present invention relates to a radiation detection element, and more particularly to repair of defective pixels of a radiation detection element.

  In recent years, radiation detection elements such as an FPD (flat panel detector) that can arrange an X-ray sensitive layer on a TFT (Thin film transistor) active matrix substrate and convert X-ray information directly into digital data have been put into practical use. Compared with conventional imaging plates, this FPD has the advantage that images can be confirmed instantly and moving images can be confirmed, and is rapidly spreading.

  Various types of radiation detecting elements of this type have been proposed. For example, a direct conversion method in which X-rays are directly converted into electric charges in a semiconductor layer and stored, or X-rays are once converted into CsI: Tl, GOS. There is an indirect conversion method in which a scintillator such as (Gd2O2S: Tb) converts light into light, and the converted light is converted into electric charges in a semiconductor layer and accumulated.

  In this radiation detection element, for example, a plurality of scanning wirings and a plurality of signal wirings are arranged so as to intersect with each other, and a switching element such as a charge storage unit and a TFT switch corresponding to each intersection of the scanning wirings and signal wirings. And a semiconductor layer is provided so as to cover the charge storage portion and the switch element at each intersection.

  In a radiographic image capturing apparatus using such a radiation detection element, when capturing a radiographic image, an X-ray is emitted, an OFF signal is output to each scanning wiring, and each switch element is turned off to turn off the semiconductor. When the charge generated in the layer is stored in each charge storage unit and the image is read out, an ON signal is sequentially output to each scanning wiring line by line, and the charge stored in each charge storage unit is read as an electric signal, A radiographic image is obtained by converting the read electrical signal into digital data.

  By the way, the radiation detection element is formed by depositing various materials on an insulating substrate and performing processes such as resist coating, exposure, development, etching, and resist stripping.

  In this radiation detection element manufacturing process, defective pixels may occur. This defective pixel may cause a leak and normal data cannot be obtained, or the data of other pixels connected to the same signal wiring as the defective pixel may be affected by the leak.

  As a technique for correcting such a defective pixel, Patent Document 1 discloses a technique for electrically irradiating a defective pixel by irradiating a laser beam to the switch element of the defective pixel to cut the wiring of the switch element portion. Are listed.

  Patent Document 2 discloses that defective pixels are separated by irradiating a defective pixel switching element by irradiating a laser beam to a defective pixel. A technique for cutting and electrically separating connected signal wirings is described.

Japanese Patent No. 4311893 JP 2001-15514 A

  However, as in the techniques described in Patent Documents 1 and 2, when the switch element part wiring is cut by irradiating the switch element of the defective pixel with the laser beam and the semiconductor layer is formed on the upper layer, the switch element is cut off. In some cases, a semiconductor is deposited on the side surface of the wiring of the switch element portion, and leakage occurs in the wiring portion of the cut switch element portion.

  Further, when the signal wiring is cut by irradiating the laser beam as in the technique described in Patent Document 2, there is no upper protective layer for protecting the signal wiring at the cut portion, and the signal wiring is leaked or corroded. There is a case.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a radiation detection element that protects a cut portion for separating a defective pixel while separating and repairing the defective pixel.

  In order to achieve the above object, the radiation detection element of the present invention has a matrix of pixels each including a sensor unit that generates charges when irradiated with radiation and a switch element for reading the charges generated in the sensor unit. And a plurality of scanning wirings through which a control signal for switching each switch element provided in each pixel flows, and an electric signal corresponding to the charge accumulated in the pixel flows according to the switching state of each switch element A defective pixel switch, comprising: a substrate provided with a plurality of signal wirings; and a protection portion formed so as to cover the detection region in which the pixels of the substrate are provided in a matrix and protecting the detection region. At least one of the scanning wiring and the signal wiring connected to the element is cut off at a portion outside the detection region and covered with the protection portion.

  The radiation detection element of the present invention is provided with a plurality of pixels in a matrix, each of which includes a sensor unit that generates charges when the substrate is irradiated with radiation and a switch element for reading the charges generated in the sensor unit. In addition, a plurality of scanning wirings through which control signals for switching each switching element provided in each pixel flow, and a plurality of signal wirings through which an electrical signal corresponding to the charge accumulated in the pixel according to the switching state of each switching element flows. Is provided. In addition, a protection portion that protects the detection region is formed so that the pixels of the substrate cover the detection region provided in a matrix.

  In the present invention, at least one of the scanning wiring and the signal wiring connected to the switch element of the defective pixel is cut off at a portion outside the detection region and covered with the protection portion. Here, a defective pixel is a pixel in which an electrostatic breakdown has occurred that breaks the insulating film between two metal layers via an insulating film, or a foreign object is mixed in. For example, a pixel in which a defective portion has occurred, a pixel in which a pinhole has occurred during deposition of an insulating film, and the like. A foreign substance refers to a substance that is different from a constituent substance that constitutes a pixel, and a substance that is mixed in a layer and a position different from the original when the pixel is composed of a plurality of layers.

  As described above, the radiation detection element according to the present invention cuts at least one of the scanning wiring and the signal wiring connected to the switch element of the defective pixel at a portion outside the detection region and covered with the protection portion. While separating and repairing the pixels, it is possible to protect the cut portion for separating the defective pixels.

  In the present invention, the sensor portion may be formed so as to cover the switch element as in the invention described in claim 2.

  Further, according to the present invention, as in the invention described in claim 3, a semiconductor layer that generates an electric charge when irradiated with radiation is individually formed in the sensor portion for each pixel, and is used as a switch element of a defective pixel. It is preferable that the connected scanning wiring is cut at least.

  Further, according to the present invention, as in the invention described in claim 4, a semiconductor layer that generates charges when irradiated with radiation is continuously formed in each pixel in the sensor unit, and the switch element of the defective pixel is formed. It is preferable that the connected signal wiring is disconnected.

  As described above, according to the present invention, there is an excellent effect that the cut portion for separating the defective pixel can be protected while the defective pixel is separated and repaired.

It is a block diagram which shows the whole structure of the radiographic imaging apparatus which concerns on 1st Embodiment. It is a top view which shows the structure of 1 pixel unit of the radiation detection element which concerns on 1st Embodiment. It is a sectional view showing a configuration of one pixel unit of the radiation detection element according to the first exemplary embodiment. It is sectional drawing which shows the whole structure of the radiation detection element which concerns on 1st Embodiment. It is a sectional view showing an example of a pixel mixed with foreign matter according to the first embodiment. It is a top view which shows an example of the cutting location of the radiation detection element which concerns on 1st Embodiment. It is a block diagram which shows the whole structure of the radiographic imaging apparatus which concerns on 2nd Embodiment. It is a top view which shows the structure of the 1 pixel unit of the radiation detection element which concerns on 2nd Embodiment. It is a line sectional view showing the composition of the 1 pixel unit of the radiation detection element concerning a 2nd embodiment. It is sectional drawing which shows the whole structure of the radiation detection element which concerns on 2nd Embodiment. It is a top view which shows an example of the cutting location of the radiation detection element which concerns on 1st Embodiment.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In the following, the case where the present invention is applied to the radiation image capturing apparatus 100 will be described.
[First Embodiment]
FIG. 1 shows an overall configuration of a radiographic image capturing apparatus 100 according to the present embodiment.

  As shown in the figure, the radiographic imaging apparatus 100 according to the present embodiment includes a direct-conversion radiation detection element 10A that directly converts radiation into electric charges.

  The radiation detection element 10 </ b> A receives the irradiated radiation to generate a sensor 103, a charge storage capacitor 5 that stores the charge generated by the sensor unit 103, and a charge stored in the charge storage capacitor 5. A plurality of pixels 7 including the TFT switches 4 are provided in a matrix in a detection region S (see FIG. 4) for detecting radiation. One electrode of the charge storage capacitor 5 is grounded via a storage capacitor wiring 102 described later, and the voltage level is set to the ground level.

  The radiation detection element 10 </ b> A includes a plurality of scanning wirings 101 for turning on / off the TFT switch 4 and a plurality of signal wirings 3 for reading out charges accumulated in the charge storage capacitor 5. It is provided crossing.

  An electric signal corresponding to the amount of charge stored in the charge storage capacitor 5 flows through each signal line 3 when any TFT switch 4 connected to the signal line 3 is turned on. Each signal wiring 3 is connected to a signal detection circuit 105 that detects an electric signal flowing out to each signal wiring 3, and each scanning wiring 101 is used to turn on / off the TFT switch 4 in each scanning wiring 101. A scan signal control device 104 for outputting the control signal is connected.

  The signal detection circuit 105 includes an amplification circuit for amplifying an input electric signal for each signal wiring 3. In the signal detection circuit 105, the electric signal input from each signal wiring 3 is amplified and detected by the amplification circuit, and thereby the amount of charge accumulated in each charge storage capacitor 5 is obtained as information of each pixel constituting the image. To detect.

  The signal detection circuit 105 and the scan signal control device 104 perform predetermined processing on the electrical signal detected by the signal detection circuit 105 and output a control signal indicating signal detection timing to the signal detection circuit 105. The signal processing device 106 is connected to the scan signal control device 104 for outputting a control signal indicating the output timing of the scan signal.

  2 and 3 show an example of the configuration of the radiation detection element 10A according to the present embodiment. 2 is a plan view showing the structure of one pixel 7 of the radiation detection element 10A according to the present embodiment, and FIG. 3 is a sectional view taken along line AA of FIG. ing.

  As shown in FIG. 3, the radiation detection element 10A has a scanning wiring 101, a storage capacitor lower electrode 18, a gate electrode 2 and a storage capacitor wiring 102 (see FIG. 2) on an insulating substrate 1 made of non-alkali glass or the like. ) Is formed. The gate electrode 2 is connected to the scanning wiring 101, and the storage capacitor lower electrode 18 is connected to the storage capacitor wiring 102. The wiring layer in which the scanning wiring 101, the storage capacitor lower electrode 18, the gate electrode 2 and the storage capacitor wiring 102 are formed (hereinafter, this wiring layer is also referred to as “first wiring layer”) is, for example, Al or Cu, Alternatively, it is formed using a laminated film mainly composed of Al or Cu.

An insulating film 15 is formed on one surface on the first wiring layer, and a portion located on the gate electrode 2 functions as a gate insulating film in the TFT switch 4. The insulating film 15 is made of, for example, SiN _X or the like, and is formed by, for example, CVD (Chemical Vapor Deposition) film formation.

  A semiconductor active layer 8 is formed at a position corresponding to the gate electrode 2 on the insulating film 15. The semiconductor active layer 8 is a channel portion of the TFT switch 4 and is made of, for example, an amorphous silicon film.

  A source electrode 9 and a drain electrode 13 are formed on these upper layers. In the wiring layer in which the source electrode 9 and the drain electrode 13 are formed, together with the source electrode 9 and the drain electrode 13, the signal wiring 3 is formed, and at a position corresponding to the storage capacitor lower electrode 18 on the insulating film 15. A storage capacitor upper electrode 16 is formed. The source electrode 9 is connected to the signal wiring 3 (see FIG. 2), and the drain electrode 13 is connected to the storage capacitor upper electrode 16. The wiring layer in which the source electrode 9, the drain electrode 13, the storage capacitor upper electrode 16, and the signal wiring 3 are formed (hereinafter, this wiring layer is also referred to as “second wiring layer”) is, for example, Al or Cu, or Al Alternatively, it is formed using a laminated film mainly composed of Cu.

  In the radiation detection element 10A according to the present exemplary embodiment, the TFT switch 4 is configured by the gate electrode 2, the gate insulating film 15, the source electrode 9, and the drain electrode 13, and the storage capacitor lower electrode 18, the gate insulating film 15, and the storage The charge storage capacitor 5 is configured by the capacitor upper electrode 16.

A TFT protective film layer 11 is formed on the entire surface (substantially the entire region) of the region where the pixel 7 is provided on the substrate 1 so as to cover the second wiring layer. The TFT protective film layer 11 is made of, for example, SiN _X or the like, and is formed by, for example, CVD film formation.

A coating type interlayer insulating film 12 is formed on the TFT protective film layer 11. This interlayer insulating film 12 is made of a photosensitive organic material having a low dielectric constant (relative dielectric constant ε _r = 2 to 4) (for example, a positive photosensitive acrylic resin: a copolymer of methacrylic acid and glycidyl methacrylate). And a base polymer mixed with a naphthoquinonediazide-based positive photosensitive agent). In the radiation detection element 10A according to the present exemplary embodiment, the interlayer insulating film 12 suppresses the capacitance between metals disposed in the upper layer and the lower layer of the interlayer insulating film 12 to be low. In general, such a material also has a function as a flattening film, and has an effect of flattening a lower step. A contact hole 17 is formed in the interlayer insulating film 12 and the TFT protective film layer 11 at a position facing the storage capacitor upper electrode 16.

  A lower electrode 18 is formed on the interlayer insulating film 12 for each pixel 7 so as to cover the pixel region while filling the contact hole 17. The lower electrode 18 is formed of an amorphous transparent conductive oxide film (ITO). And is connected to the storage capacitor upper electrode 16 through the contact hole 17.

  A semiconductor layer 20 made of amorphous a-Se (amorphous selenium) is uniformly formed on almost the entire surface of the detection region S provided with the pixels 7 on the substrate 1 on the lower electrode 18. The semiconductor layer 20 generates charges (electrons-holes) inside when irradiated with radiation such as X-rays.

  An upper electrode 22 is formed on the semiconductor layer 20. In the radiation detection element 10 </ b> A according to the present embodiment, the sensor unit 103 is configured by the upper electrode 22, the semiconductor layer 20, and the lower electrode 18.

  The upper electrode 22 is connected to a bias power source (not shown), and a bias voltage is supplied from the bias power source. The electric charge generated in the semiconductor layer 20 moves to the upper electrode 22 or the lower electrode 18 according to the polarity of the electric charge by an electric field generated by a bias voltage applied from the upper electrode 22.

  A photoelectric conversion material such as amorphous selenium used for the semiconductor layer 20 is likely to be deteriorated due to environmental changes such as heat, humidity, contamination, and so on, and thus needs some cover. Further, since a high voltage of 1 to 10 kV is applied to the upper electrode 22, it is necessary to ensure a sufficient breakdown voltage.

  For this reason, the direct conversion type radiation detection element 10A according to the present exemplary embodiment is provided with a cover glass 30 as an upper substrate covering the upper electrode 22 on the upper part of the device on the upper electrode 22, as shown in FIG. ing. In the present embodiment, non-alkali glass made of the same material as the substrate 1 is employed as the cover glass 30.

  The substrate 1 is provided with a rib member 31 that supports the cover glass 30. The rib material 31 is made of, for example, a resin material such as acrylic resin, and surrounds the detection region S where the semiconductor layer 20 is formed.

  The outer peripheral portion of the cover glass 30 is bonded to the rib material 31 and is supported by the rib material 31.

  A space surrounded by the cover glass 30, the rib material 31, and the substrate 1 is filled with a curable resin 32 as a filling member, and the detection region S is protected. As the curable resin 32, for example, a room temperature curable resin such as epoxy or silicon is used.

  By the way, in the radiation detection element 10 </ b> A, defective pixels 7 </ b> A may occur in the manufacturing process of forming each layer on the substrate 1.

  FIG. 5 shows an example in which foreign matter 40 is mixed into the TFT switch 4 portion. When the foreign matter 40 is mixed in this way, a leak occurs from the TFT switch 4 and becomes a defective pixel 7A.

  Therefore, in the present embodiment, as shown in FIG. 6, at the stage where the formation of each layer on the substrate 1 is finished, at least one of the occurrence of leakage of each pixel 7 and the adhesion of foreign matter is inspected to thereby detect the defective pixel 7A. Perform detection. Then, at least one of the scanning wiring 101 and the signal wiring 3 connected to the TFT switch 4 of the defective pixel 7A is covered with the curable resin 32 outside the detection region S (arrow T portion in FIG. 4). Irradiation and cutting are performed, and the defective pixel 7A is electrically separated to perform repair. When the scanning wiring 101 is cut, the control signal does not flow from the scanning signal control device 104 to the scanning wiring 101, and the charge is not read from the defective pixel 7A, and the scanning wiring direction including the defective pixel 7A The pixel column becomes a line defect. When the signal wiring 3 is cut, the electrical signal read from the defective pixel 7A is not transmitted to the signal detection circuit 105, and the pixel column in the scanning wiring direction including the defective pixel 7A becomes a line defect.

  Note that, when the semiconductor layer 20 is continuous in each pixel 7 as in the radiation detection element 10A according to the present exemplary embodiment, when the scanning wiring 101 connected to the TFT switch 4 of the defective pixel 7A is cut, the defective pixel The charges accumulated in the lower electrode 18 of 7A are accumulated without being released, and the electric field in the semiconductor layer 20 is distorted by the charges accumulated in the lower electrode 18 of the defective pixel 7A. May be affected. In such a case, it is preferable to cut only the signal wiring 3 side.

  After this repair, the rib material 31 is formed on the substrate 1, the cover glass 30 is fixed, and the curable resin 32 is filled.

  As described above, in the radiation detection element 10A according to the present exemplary embodiment, at least one of the scanning wiring 101 and the signal wiring 3 connected to the TFT switch 4 of the defective pixel 7A is outside the detection region S and is curable as a protection unit. By cutting at the portion covered with the resin 32, the cut portion for separating the defective pixel 7A can be protected while separating and repairing the defective pixel 7A.

  Further, in the radiation detection element 10A according to the present exemplary embodiment, since the semiconductor layer 20 is continuous in each pixel 7, for example, when only the defective pixel 7A is electrically separated and repaired as a point defect, The semiconductor layer 20 is also cut, and a leak occurs at the end face of the wiring exposed by repairing the semiconductor layer 20. For this reason, in the radiation detection element 10A in which the semiconductor layer 20 is continuous in each pixel 7 as in the present embodiment, at least one of the scanning wiring 101 and the signal wiring 3 is cut outside the detection region S to thereby detect the defective pixel 7A. It is preferable to perform the repair.

  Moreover, since the radiation detection element 10A according to the present embodiment can also protect the cut portion for separating the defective pixel 7A by the curable resin 32 that protects the detection region S, a protection member for protecting the cut portion is provided. There is no need to provide it separately. Thereby, the manufacturing process at the time of manufacturing 10 A of radiation detection elements does not increase.

Note that in the radiation detection element 10A according to the first embodiment, data of each pixel 7 connected to the cut scanning wiring 101 and the signal wiring 3 cannot be obtained, resulting in a line defect. For example, the signal processing device The position information indicating the position of each pixel 7 that becomes a line defect is stored in advance in 106, the position of each pixel 7 that is a line defect is obtained based on the position information in the signal processing device 106, and each pixel 7 that becomes a line defect is obtained. Can be generated by performing an interpolation process from data of normal pixels 7 adjacent to each pixel 7 that is a line defect.
[Second Embodiment]
Next, as a second embodiment, a case will be described in which the present invention is applied to an indirect conversion type radiation detection element 10B that converts radiation once into light and converts the converted light into electric charge.

  FIG. 7 shows an overall configuration of a radiographic imaging apparatus 100 using the radiation detection element 10B according to the second exemplary embodiment. Note that portions corresponding to those in the first embodiment (FIG. 1) are denoted by the same reference numerals as those in the first embodiment. Also, a scintillator that converts radiation into light is omitted.

  The radiation detection element 10 </ b> B has a pixel 7 configured to include a sensor unit 103 that receives light and accumulates charges and a TFT switch 4 for reading the charges accumulated in the sensor unit 103. Many are provided in the shape.

  Further, in the radiation detection element 10B, a plurality of scanning wirings 101 for turning on / off the TFT switch 4 and a plurality of signal wirings 3 for reading out electric charges accumulated in the sensor unit 103 intersect each other. Is provided.

  A signal detection circuit 105 is connected to each signal line 3, and a scan signal control device 104 is connected to each scan line 101. A signal processing device 106 is connected to the signal detection circuit 105 and the scan signal control device 104.

  FIG. 8 is a plan view showing the structure of one pixel unit of the radiation detection element 10B of the indirect conversion type according to the present embodiment, and FIG. 9 is a sectional view taken along line AA of FIG. Has been.

  As shown in FIG. 9, in the radiation detection element 10B, a scanning wiring 101 and a gate electrode 2 are formed on an insulating substrate 1 made of alkali-free glass or the like, and the scanning wiring 101 and the gate electrode 2 are connected. (See FIG. 8).

  On the scanning wiring 101 and the gate electrode 2, an insulating film 15 is formed on one surface so as to cover the scanning wiring 101 and the gate electrode 2.

  On the gate electrode 2 on the insulating film 15, the semiconductor active layer 8 is formed in an island shape.

  A source electrode 9 and a drain electrode 13 are formed on these upper layers. In the wiring layer in which the source electrode 9 and the drain electrode 13 are formed, the signal wiring 3 is formed together with the source electrode 9 and the drain electrode 13. The source electrode 9 is connected to the signal wiring 3 (see FIG. 8).

  An impurity doped semiconductor layer (not shown) made of doped amorphous silicon or the like is formed between the source electrode 9 and drain electrode 13 and the semiconductor active layer 8. These constitute the TFT switch 4 for switching.

  A TFT protective film layer 11 is formed on almost the whole area (substantially the entire area) of the area on the substrate 1 where the pixels 7 are provided, covering the semiconductor active layer 8, the source electrode 9, the drain electrode 13, and the signal wiring 3. Has been.

  A coating type interlayer insulating film 12 is formed on the TFT protective film layer 11. In the radiation detection element 10B according to this exemplary embodiment, a contact hole 17 is formed at a position facing the drain electrode 13 of the interlayer insulating film 12 and the TFT protective film layer 11.

  A lower electrode 18 of the sensor unit 103 is formed on the interlayer insulating film 12 so as to cover the pixel region while filling the contact hole 17, and this lower electrode 18 is connected to the drain electrode 13 of the TFT switch 4. ing. If the semiconductor layer 21 described later is as thick as about 1 μm, the material of the lower electrode 18 is not limited as long as it has conductivity. Therefore, there is no problem if it is formed using a conductive metal such as Al-based material or ITO.

  On the other hand, when the semiconductor layer 21 is thin (around 0.2 to 0.5 μm), light is not sufficiently absorbed by the semiconductor layer 21, so that an increase in leakage current due to light irradiation to the TFT switch 4 is prevented. An alloy mainly composed of a light-shielding metal or a laminated film is preferable.

A semiconductor layer 21 that functions as a photodiode is formed on the lower electrode 18. In the present embodiment, a PIN structure photodiode in which an n ⁺ layer, an i layer, and a p ⁺ layer (n ⁺ amorphous silicon, amorphous silicon, and p ⁺ amorphous silicon) are stacked is employed as the semiconductor layer 21. To n ⁺ layer 21A, i layer 21B, and p ⁺ layer 21C are sequentially stacked. The i layer 21 </ b> B generates charges (a pair of free electrons and free holes) when irradiated with light. The n ⁺ layer 21A and the p ⁺ layer 21C function as a contact layer, and electrically connect the lower electrode 18 and an upper electrode 22 described later to the i layer 21B.

  In the present embodiment, the lower electrode 18 is made larger than the semiconductor layer 21, and the light irradiation side of the TFT switch 4 is covered with the semiconductor layer 21. As a result, the ratio of the area that can receive light in the pixel region (so-called fill factor) is increased, and light incidence on the TFT switch 4 is suppressed.

  On each semiconductor layer 21, an upper electrode 22 is formed individually. For the upper electrode 22, for example, a material having high light transmittance such as ITO or IZO (zinc oxide indium) is used. In the radiation detection element 10 </ b> B according to the present embodiment, the sensor unit 103 is configured by the upper electrode 22, the semiconductor layer 21, and the lower electrode 18.

  A protective insulating film 23 is formed on the interlayer insulating film 12, the semiconductor layer 21, and the upper electrode 22 so as to have an opening 27 </ b> A in a part corresponding to the upper electrode 22. The protective insulating film 23 is made of, for example, SiNx, like the TFT protective film layer 11, and is formed by, for example, CVD film formation.

  On the protective insulating film 23, the common electrode wiring 25 is formed of Al or Cu, or an alloy or a laminated film mainly composed of Al or Cu. The common electrode wiring 25 has a contact pad 27 formed in the vicinity of the opening 27A, and is electrically connected to the upper electrode 22 through the opening 27A of the protective insulating film 23.

  In the radiation detection element 10B formed in this way, a protective film 24 is formed of an insulating material having a lower light absorption as required. As shown in FIG. A scintillator 29 made of GOS or the like is attached using a low adhesive resin.

  Incidentally, in the radiation detection element 10B, defective pixels 7A may occur in the manufacturing process of forming each layer on the substrate 1.

  Therefore, also in the present embodiment, at the stage where the formation of each layer on the substrate 1 is completed, the defective pixel 7A is detected by inspecting at least one of the occurrence of leakage of each pixel 7 and the adhesion of foreign matter, thereby detecting the defective pixel. At least one of the scanning wiring 101 and the signal wiring 3 connected to the TFT switch 4 of 7A is cut off by irradiating with a laser beam at a portion outside the detection region S and covered by the scintillator 29 to electrically isolate the defective pixel 7A. And repair.

  When the semiconductor layer 20 is separated at each pixel 7 as in the radiation detection element 10B according to the present embodiment, either the scanning wiring 101 or the signal wiring 3 may be cut, or both may be cut. Also good.

  FIG. 11 shows an example in which the signal wiring 3 connected to the TFT switch 4 of the defective pixel 7A is cut.

  In addition, when the scan wiring 101 is cut, a control signal does not flow from the scan signal control device 104 to the scan wiring 101, and no voltage is applied to the defective pixel 7A. Leakage at the pixel 7A can be prevented.

  After this repair, the scintillator 29 is attached to the substrate 1 to protect the detection region S.

  Thus, also in the radiation detection element 10B according to the present exemplary embodiment, at least one of the scanning wiring 101 and the signal wiring 3 connected to the switch element of the defective pixel 7A is outside the detection region S and is a scintillator 29 as a protection unit. By cutting at the portion covered with, the cut portion for separating the defective pixel 7A can be protected while the defective pixel 7A is separated and repaired.

  In addition, the radiation detection element 10B according to the present embodiment can also protect the cut portion for separating the defective pixel 7A by the scintillator 29, so that it is not necessary to separately provide a protective member for protecting the cut portion. Thereby, the manufacturing process at the time of manufacturing the radiation detection element 10B does not increase.

  Further, in the radiation detection element 10B according to the present exemplary embodiment, the semiconductor layer 21 covers the light irradiation side of the TFT switch 4, so that, for example, only the defective pixel 7A is electrically separated and repaired as a point defect. In this case, the semiconductor layer 21 is also cut, and a leak occurs at the end face of the wiring exposed by repairing with the semiconductor layer 21. In order to prevent the occurrence of this leak, for example, when the semiconductor layer 21 and the TFT switch 4 are formed so as not to overlap, the fill factor in the pixel region decreases. Therefore, in the radiation detection element 10B in which the light irradiation side of the TFT switch 4 is covered with the semiconductor layer 21 as in the present embodiment, at least one of the scanning wiring 101 and the signal wiring 3 is cut outside the detection region S. It is preferable to repair the defective pixel 7A.

  Even in the radiation detection element 10B according to the second embodiment, data of each pixel 7 connected to the cut scanning wiring 101 and the signal wiring 3 cannot be obtained, which results in a line defect. The apparatus 106 stores in advance position information indicating the position of each pixel 7 that becomes a line defect, and the signal processing apparatus 106 obtains the position of each pixel 7 that becomes a line defect based on the position information. Data of the pixel 7 can be generated by performing interpolation processing from data of a normal pixel 7 adjacent to each pixel 7 that is a line defect.

  In each of the above-described embodiments, the case where the repaired portion is protected by a protective portion such as the curable resin 32 or the scintillator 29 after the defective pixel 7A is repaired is not limited to this. For example, when the curable resin 32 or the scintillator 29 is thick enough to be cut by the laser beam at the time of repair and the cut portion of the wiring can be protected, after the substrate 1 is protected by the curable resin 32 or the scintillator 29 first, You may make it repair a defective pixel 7A by irradiating a laser beam from the back surface (surface in which the sensor part 103 is not formed) side of the board | substrate 1. FIG.

  In the second embodiment, the case where the sensor unit 103 (semiconductor layer 21) covers the light irradiation side (the upper surface side of the substrate 1) of the TFT switch 4 has been described. However, the present invention is not limited to this. It is not a thing. For example, in the case where the sensor unit 103 is formed so as to cover the TFT switch 4 on the lower layer side than the TFT switch 4, the laser beam is irradiated to electrically isolate only the defective pixel 7A and attempt to repair it as a point defect. In this case, the sensor unit 103 is also cut, and leakage occurs at the end face of the wiring exposed by the sensor unit 103 and repair. That is, when the sensor unit 103 is formed so as to cover the TFT switch 4 and the region of the sensor unit 103 and the TFT switch 4 overlaps, at least one of the scanning wiring 101 and the signal wiring 3 is cut outside the detection region S. It is preferable to repair the defective pixel 7A.

  In each of the above embodiments, the case where non-alkali glass is used as the substrate 1 has been described. However, the present invention is not limited to this. For example, the insulating substrate 1 may be formed using an insulator such as polyimide. The material of the substrate is not limited to this.

  In the first embodiment, the case where the semiconductor layer 20 is continuous in each pixel 7 in the direct-conversion radiation detection element 10A has been described. However, the present invention is not limited to this. For example, the present invention may be applied when the photodiode layer is continuous in each pixel. FIGS. 5 and 6 of JP-T-2008-50596 show an example in which the photodiode layers are continuous in each pixel.

  The radiation detection elements 10A and 10B may be irradiated with radiation from the front side where the sensor unit 103 is provided, or may be irradiated with radiation from the substrate 1 side (back side). Here, in the radiation detection element 10B of the indirect conversion method, when radiation is irradiated from the front side, light is emitted more strongly on the upper surface side (opposite side of the substrate 1) of the scintillator 29, and when radiation is irradiated from the back side, 1 is incident on the scintillator 29, and the substrate 1 side of the scintillator 29 emits light more intensely. Electric charges are generated in the semiconductor layer 21 by the light generated by the scintillator 29. For this reason, the radiation detection element 10B of the indirect conversion method is designed to have higher sensitivity to radiation because radiation does not pass through the substrate 1 when radiation is irradiated from the front side than when radiation is irradiated from the back side. Moreover, since the light emission position of the scintillator 29 with respect to each semiconductor layer 21 is closer when the radiation is irradiated from the back side than when the radiation is irradiated from the front side, the radiation image obtained by imaging High resolution.

  In each of the above embodiments, the case where the present invention is applied to the radiographic imaging apparatus 100 that detects an image by detecting X-rays has been described. However, the present invention is not limited to this, for example, The electromagnetic wave to be detected may be visible light, ultraviolet light, infrared light, or the like.

  In addition, the configuration of the radiographic image capturing apparatus 100 (see FIGS. 1 and 7) and the configuration of the radiation detection elements 10A and 10B (FIGS. 2 to 6 and FIGS. 8 to 11) described in the above embodiments are examples. Needless to say, modifications can be made as appropriate without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Board | substrate 3 Signal wiring 4 TFT switch 7 Pixel 7A Defective pixel 10A, 10B Radiation detection element 20, 21 Semiconductor layer 29 Scintillator 32 Curable resin 40 Foreign material 101 Scanning wiring 103 Sensor part

Claims (4)

A plurality of pixels having a sensor unit that generates charges when irradiated with radiation and a switch element for reading out the charges generated in the sensor unit are provided in a matrix, and each switch element provided in each pixel is switched. A substrate provided with a plurality of scanning wirings through which control signals flow and a plurality of signal wirings through which electrical signals according to the electric charges accumulated in the pixels flow according to the switching state of each switch element;
A protection unit that protects the detection region, the pixel of the substrate being formed so as to cover the detection region provided in a matrix;
A radiation detection element in which at least one of the scanning wiring and the signal wiring connected to a switch element of a defective pixel is cut off at a portion outside the detection region and covered with the protection portion. The radiation detection element according to claim 1, wherein the sensor unit is formed to cover the switch element. In the sensor unit, a semiconductor layer that generates charges when irradiated with radiation is individually formed for each pixel,
The radiation detection element according to claim 1, wherein at least the scanning wiring connected to the switch element of the defective pixel is cut off. In the sensor unit, a semiconductor layer that generates charges when irradiated with radiation is continuously formed in each pixel,
The radiation detection element according to claim 1, wherein the signal wiring connected to the switch element of the defective pixel is cut off.

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