JP2013077788A - Semiconductor element, radiation detector, and manufacturing method of semiconductor element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor element which inhibits corrosion of a lower electrode which is caused by moisture, a radiation detector, and a manufacturing method of the semiconductor element.SOLUTION: A gate pad 40 and a data pad 50 are formed while contact holes formed by etching an interlayer dielectric film 23 and a TFT protection layer 30 are buried. Thus, the data pad 50 and a second signal wiring layer 52 are connected with each other without a lower electrode 11 interposed therebetween. Further, the gate pad 40 and a first signal wiring layer 42 are connected with each other. Thus, the lower electrode 11 is not provided at an opening of a protection layer 34, corrosion is less likely to occur even when moisture intrudes, and corrosion of the lower electrode 11 is inhibited.

Description

  The present invention relates to a semiconductor element, a radiation detector, and a method for manufacturing a semiconductor element, and more particularly to a semiconductor element having an external connection terminal, a radiation detector, and a method for manufacturing the semiconductor element.

  2. Description of the Related Art Conventionally, a radiographic imaging apparatus that performs radiography for medical diagnosis and the like is known. The radiation image capturing apparatus captures a radiation image by detecting radiation that has been irradiated from the radiation irradiating apparatus and transmitted through the subject with a radiation detector. The radiographic image capturing apparatus captures a radiographic image by collecting and reading out charges generated according to the irradiated radiation.

  Such a radiographic imaging apparatus includes a radiation detector that detects radiation. The radiation detector includes a wavelength conversion layer that converts irradiated radiation into light, and a photoelectric conversion layer that generates charges when irradiated with light converted by the wavelength conversion layer. The charges generated in are collected by the lower electrode provided at the lower part of the photoelectric conversion layer. The charge collected by the lower electrode is read by the switching element, and an electric signal corresponding to the charge is output.

  In such a radiation detector, a plurality of control wirings for supplying a control signal for turning on / off a switching element in order to read out charges from each pixel, and charges read out from each pixel are output. A plurality of signal wirings are provided. Each of the control wiring and the signal wiring is electrically connected to an external circuit or the like via an external connection terminal (pad).

  For example, in Patent Document 1, in a stacked radiation detection panel in which a photoelectric conversion element is formed on a switch element, a gate drive driving circuit connection means corresponding to an external connection terminal is connected to a gate line. The structure is described.

JP 2009-133837 A

  Generally, in a conventional radiation detector, a switching element is formed on a substrate. Control wiring is formed on the substrate, and signal wiring is further formed thereon. A lower electrode is formed on these upper layers, and a photoelectric conversion layer is formed on the lower electrodes. An upper electrode is formed on the photoelectric conversion layer, and a bias wiring for applying a bias voltage to the upper electrode is formed on the upper electrode. Furthermore, a protective layer is formed on these upper layers so as to cover the radiation detector.

  In general, in such a conventional radiation detector, the uppermost protective layer is opened at the end of the radiation detector, and an external connection terminal is formed in the opening. The external connection terminal is connected to the signal wiring via the lower electrode or further to the control wiring via the signal wiring by using the lower electrode as a relay electrode (see FIGS. 9 and 11).

  When forming the photoelectric conversion layer, the photoelectric conversion layer is patterned and etched by dry etching or wet etching, but the lower electrode used as a relay electrode may be damaged during this etching. is there.

  As described above, since the external connection terminal is provided in the opening of the protective layer, the external connection terminal is not covered with the protective layer, and moisture or other moisture easily enters. When the invaded moisture reaches the damaged lower electrode, there is a concern that a so-called electric contact that is electrochemical corrosion (corrosion) occurs.

  The present invention has been made to solve the above-described problems, and provides a semiconductor element, a radiation detector, and a method of manufacturing a semiconductor element that can suppress corrosion of the lower electrode due to moisture. Objective.

  In order to achieve the above object, a semiconductor device according to claim 1 includes a photoelectric conversion layer that generates charges according to received light, a lower electrode that collects charges generated in the photoelectric conversion layer, and the lower portion. A switching element that reads and outputs charges collected by the electrodes according to a control signal, a signal wiring that outputs the charges read by the switching element, and a control wiring that supplies the control signal to the switching element A wiring layer that forms at least one of the wiring layer, and an external connection terminal that is connected to the wiring layer without the lower electrode and connects the wiring layer to the outside.

  According to another aspect of the present invention, there is provided a bias wiring for applying a bias voltage to the photoelectric conversion layer on the photoelectric conversion layer formed on the wiring layer, as in the semiconductor element according to claim 2, The connection terminal is preferably in the same layer as the bias wiring.

  Moreover, the radiation detector of Claim 3 is a said wavelength conversion layer which converts the irradiated radiation into light, and the light converted by the said wavelength conversion layer is irradiated to the said Claim 1 or the said Claim 2 And the semiconductor element described.

  The method for manufacturing a semiconductor device according to claim 4 includes a step of forming a wiring layer on a substrate, a step of forming a first insulating film on the wiring layer, and a photoelectric conversion on the first insulating film. Forming a layer; forming a second insulating film on the photoelectric conversion layer; etching the first insulating film and the second insulating film to form the first insulating film and the second insulating film; Forming a contact hole penetrating therethrough and forming an external connection terminal on the second insulating film to fill the contact hole and connect the wiring layer to the outside.

  In a general semiconductor device manufacturing method, a wiring layer is formed on a substrate, a first insulating film is formed on the wiring layer, a contact hole penetrating the first insulating film is formed, and the first insulating film is formed on the first insulating film. Form a photoelectric conversion layer, form a second insulating film on the photoelectric conversion layer, form a contact hole that penetrates the second insulating film, fill the contact hole, and connect the wiring layer to the outside through the lower electrode An external connection terminal is formed for this purpose.

  Generally, the photoelectric conversion layer is formed by a process including a process of patterning and etching a photoelectric conversion film formed on the first insulating film. During the etching, the wiring layer in the contact hole that penetrates the first insulating film may be damaged.

  Therefore, in the present invention, after the second insulating film is formed on the photoelectric conversion layer, the first insulating film and the second insulating film are etched to collectively form contact holes that penetrate the first insulating film and the second insulating film. Then, an external connection terminal for filling the contact hole and connecting the wiring layer to the outside is formed on the second insulating film. Thereby, the damage by the etching in the formation process of a photoelectric converting layer can be suppressed, As a result, the corrosion by a water | moisture content can be suppressed.

  As described above, there is an effect that corrosion of the lower electrode due to moisture can be suppressed.

It is a block diagram which shows an example of the whole structure of the radiographic imaging apparatus which concerns on this Embodiment. It is a top view which shows an example of a structure of the radiation detector concerning this Embodiment. It is sectional drawing of an example of the pixel of the radiation detector which concerns on this Embodiment shown in FIG. It is a top view which shows an example of a structure of the data pad which concerns on this Embodiment. FIG. 5 is a cross-sectional view of an example of a data pad according to the present embodiment shown in FIG. 4. It is explanatory drawing explaining the manufacturing process of the data pad which concerns on this Embodiment. It is a top view which shows an example of a structure of the gate pad which concerns on this Embodiment. It is sectional drawing of an example of the gate pad which concerns on this Embodiment shown in FIG. It is sectional drawing of an example of the gate pad in the conventional radiation detector. It is explanatory drawing explaining the manufacturing process of the conventional gate pad. It is sectional drawing of an example of the gate pad in the conventional radiation detector.

  Hereinafter, an example of the present embodiment will be described with reference to the drawings.

  First, a schematic configuration of the radiographic image capturing apparatus 100 of the present embodiment will be described. In FIG. 1, an example of the whole structure of the radiographic imaging apparatus of this Embodiment is shown. In the present embodiment, a case will be described in which the present invention is applied to an indirect conversion radiation detector 10 that once converts radiation such as X-rays into light and converts the converted light into electric charges. In the present embodiment, the radiographic image capturing apparatus 100 includes an indirect conversion type radiation detector 10. In FIG. 1, a scintillator that converts radiation into light is omitted.

  The radiation detector 10 includes a sensor unit 103 that receives light to generate electric charge, accumulates the generated electric charge, and a TFT switch 4 that is a switching element for reading out the electric charge accumulated in the sensor unit 103. A plurality of pixels 20 are arranged in a matrix. In this embodiment mode, charges are generated in the sensor unit 103 by irradiation with light converted by the scintillator.

  A plurality of pixels 20 are arranged in a matrix in one direction (the horizontal direction in FIG. 1, hereinafter also referred to as “row direction”) and the direction intersecting the row direction (the vertical direction in FIG. 1, hereinafter also referred to as “column direction”). ing. In FIG. 1, the arrangement of the pixels 20 is shown in a simplified manner. For example, 1024 × 1024 pixels 20 are arranged in the row direction and the column direction.

  Further, the radiation detector 10 receives, on the substrate 1 (see FIG. 2), the scanning wiring 101 which is a plurality of control wirings for turning on / off the TFT switch 4 and the electric charge accumulated in the sensor unit 103. A plurality of signal wirings 3 for reading are provided so as to cross each other. In the present embodiment, one signal wiring 3 is provided for each pixel column in one direction, and one scanning wiring 101 is provided for each pixel column in the intersecting direction. When 1024 × 1024 are arranged in the column direction, 1024 signal wirings 3 and scanning wirings 101 are provided.

  Further, the radiation detector 10 is provided with a bias wiring 25 in parallel with each signal wiring 3. One end and the other end of the bias wiring 25 are connected in parallel, and one end is connected to a bias power supply 110 that supplies a predetermined bias voltage. The sensor unit 103 is connected to the bias wiring 25, and a bias voltage is applied via the bias wiring 25.

  A scanning signal for switching each TFT switch 4 flows through the scanning wiring 101. In this way, each TFT switch 4 is switched (ON / OFF) by the scan signal flowing through each scan line 101.

  An electric signal corresponding to the electric charge accumulated in each pixel 20 flows through the signal wiring 3 in accordance with the switching state of the TFT switch 4 of each pixel 20. More specifically, an electrical signal corresponding to the amount of charge accumulated by turning on any TFT switch 4 of the pixel 20 connected to the signal wiring 3 flows to each signal wiring 3.

  Each signal wiring 3 of the radiation detector 10 is connected to a signal detection circuit 105 that detects an electric signal flowing out to each signal wiring 3 via a data pad 50 that is an external connection terminal. In addition, a scanning signal control circuit that outputs a control signal for turning on / off the TFT switch 4 to each scanning wiring 101 to each scanning wiring 101 of the radiation detector 10 via a gate pad 40 that is an external connection terminal. 104 is connected. In FIG. 2, the signal detection circuit 105 and the scan signal control circuit 104 are shown in a simplified form. However, for example, a plurality of signal detection circuits 105 and a plurality of scan signal control circuits 104 are provided (for example, 256). The signal wiring 3 or the scanning wiring 101 is connected every time. For example, when 1024 signal wires 3 and 1024 scan wires 101 are provided, four scan signal control circuits 104 are provided, 256 scan wires 101 are connected, and four signal detection circuits 105 are provided 256. The signal wiring 3 is connected one by one.

  The signal detection circuit 105 incorporates an amplification circuit (not shown) for amplifying an input electric signal for each signal wiring 3. In the signal detection circuit 105, an electric signal input from each signal wiring 3 is amplified by an amplifier circuit and converted into a digital signal by an ADC (analog / digital converter).

  The signal detection circuit 105 and the scan signal control circuit 104 are subjected to predetermined processing such as noise removal on the digital signal converted by the signal detection circuit 105, and the signal detection circuit 105 is provided with a signal detection timing. A control unit 106 that outputs a control signal indicating the timing of outputting the scan signal is connected to the scan signal control circuit 104.

  The control unit 106 according to the present embodiment is configured by a microcomputer, and includes a nonvolatile storage unit including a CPU (Central Processing Unit), a ROM and a RAM, a flash memory, and the like. The control unit 106 generates and outputs an image indicated by the irradiated radiation based on the electrical signal indicating the charge information input from the signal detection circuit 105.

  Next, the configuration of the pixel 20, the gate pad 40, and the data pad 50 of this embodiment will be described with a specific example. First, the pixel 20 will be described. FIG. 2 is a plan view showing a structure of 2 pixels × 2 pixels of the indirect conversion type radiation detector 10 according to the present embodiment. FIG. 3 is a cross-sectional view taken along line AA of the pixel 20 in FIG.

  As shown in FIG. 3, the pixel 20 includes a scanning wiring 101 (see FIG. 2) and a gate electrode 2 formed on an insulating substrate 1 made of alkali-free glass or the like. Are connected (see FIG. 2). The wiring layer in which the scanning wiring 101 and the gate electrode 2 are formed (hereinafter, this wiring layer is also referred to as “first signal wiring layer 42”) uses Al or Cu, or a laminated film mainly composed of Al or Cu. However, the present invention is not limited to these.

An insulating film 15 is formed on one surface on the first signal wiring layer 42, 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.

  On the gate electrode 2 on the insulating film 15, the semiconductor active layer 8 is formed in an island shape. 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, 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. 2). The wiring layer in which the source electrode 9, the drain electrode 13, and the signal wiring 3 are formed (hereinafter, this wiring layer is also referred to as “second signal wiring layer 52”) is mainly Al or Cu, or Al or Cu. Although a laminated film is used, it is not limited to these. Between the source electrode 9 and the drain electrode 13 and the semiconductor active layer 8, an impurity-added semiconductor layer (not shown) made of impurity-added amorphous silicon or the like is formed. These constitute the TFT switch 4 for switching. In the TFT switch 4, the source electrode 9 and the drain electrode 13 are reversed depending on the polarity of charges collected and accumulated by the lower electrode 11 described later.

In order to protect the TFT switch 4 and the signal wiring 3 over almost the entire area (substantially the entire area) where the pixels 20 are provided on the substrate 1 so as to cover the second signal wiring layer 52, the TFT protective film layer 30. Is formed. The TFT protective film layer 30 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 30. The interlayer insulating film 12 is a photosensitive organic material having a low dielectric constant (relative dielectric constant εr = 2 to 4) (for example, a positive photosensitive acrylic resin: a base made of a copolymer of methacrylic acid and glycidyl methacrylate). And a film obtained by mixing a naphthoquinonediazide-based positive photosensitive agent with a polymer).

  In the radiation detector 10 according to the present exemplary embodiment, the interlayer insulating film 12 suppresses the capacitance between metals disposed in the upper and lower layers 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. In the radiation detector 10 according to the present 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 30.

  A lower electrode 11 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 the lower electrode 11 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 lower electrode 11 is formed of a conductive metal such as an Al-based material, for example, as long as it has conductivity.

  A semiconductor layer 21 that functions as a photodiode is formed on the lower electrode 11. 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, p + amorphous silicon) are stacked is employed as the semiconductor layer 21, and the n + layer 21A is formed from the lower layer. , 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 contact layers, and electrically connect the lower electrode 11 and an upper electrode 22 (described later) and the i layer 21B.

  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 detector 10 according to the present exemplary embodiment, the sensor unit 103 includes the upper electrode 22, the semiconductor layer 21, and the lower electrode 11.

On the interlayer insulating film 12, the semiconductor layer 21, and the upper electrode 22, a coating type interlayer insulating film 23 is formed so as to have a part of the opening 27 </ b> A corresponding to the upper electrode 22 and cover each semiconductor layer 21. Yes. The interlayer insulating film 23 is made of SiN _X or the like, and is formed by CVD film formation with a film thickness of 0.2 to 0.6 μm, for example.

  A bias wiring 25 is formed on the interlayer insulating film 23. The bias wiring 25 is preferably a transparent conductor, Al or Cu, an alloy mainly composed of Al or Cu, or a laminated film, and particularly preferably a transparent conductor. As the transparent conductor, for example, a highly light-transmitting conductor such as ITO or IZO (zinc indium oxide) is preferable. The bias wiring 25 has a contact pad 27 formed in the vicinity of the opening 27 </ b> A and is electrically connected to the upper electrode 22 through the opening 27 </ b> A of the interlayer insulating film 23.

  Further, a planarizing layer 32 for planarizing the surface is formed on the interlayer insulating film 23 and the bias wiring 25 (contact pad 27). The planarization layer 32 is an insulating layer, and is formed of an organic material with a thickness of 1 to 4 μm, for example, like the interlayer insulating film 12. A protective layer 34 for protecting the surface of the radiation detector 10 is formed on the planarization layer 32.

  On the pixel 20 formed in this manner, a protective film is formed of an insulating material having a low light absorption as necessary, and an adhesive resin having a low light absorption is used on the surface thereof, or directly. A scintillator made of GOS, CsI or the like is attached by vapor deposition.

  Next, the data pad 50 of the present embodiment will be described. FIG. 4 is a plan view showing an example of the structure of the end portion of the radiation detector 10 in which the data pad 50 according to the present embodiment is arranged. FIG. 5 shows a cross-sectional view of an example of an end portion of the radiation detector 10 on which the data pad 50 is arranged.

As shown in FIG. 5, an insulating film 15 is formed on the substrate 1. A second signal wiring layer 52 (a wiring layer including the signal wiring 3, the source electrode 9, and the drain electrode 13) is formed on the insulating film 15, and the insulating film 15 and the second signal wiring layer 52 are formed. A TFT protective layer 30 is formed on the TFT protective layer 30. An interlayer insulating film 23 is formed on the TFT protective layer 30 at the end of the radiation detector 10 where the data pad 50 is provided. . A protective layer 34 having an opening in the region where the data pad 50 is formed is formed on the interlayer insulating film 23. A data pad 50 is formed in the opening of the protective layer 34 on the interlayer insulating film 23, and the data pad 50 and the second signal wiring layer 52 penetrate the interlayer insulating film 23 and the TFT protective layer 30. The contact hole 36 is electrically connected directly.

  A manufacturing process of the data pad 50 of the present embodiment will be described with reference to FIG.

  First, in the radiation detector 10, the gate electrode 2 and the scanning wiring 101 are formed on the substrate 1 as the second signal wiring layer 52 line layer. The first signal wiring layer 42 is a laminated film with a barrier metal layer made of a low resistance metal such as Al or Al alloy or a refractory metal, and has a film thickness of about 100 to 600 nm on the substrate 1 by sputtering. It is deposited on. Thereafter, the resist film is patterned by photolithography. Thereafter, the metal film is patterned by a wet etch method using an etchant for Al or a dry etch method. Thereafter, the first signal wiring layer 42 is completed by removing the resist. Next, the insulating film 15, the semiconductor active layer 8, and the contact layer are sequentially deposited on the first signal wiring layer 42. The insulating film 15 is made of SiNx and has a thickness of 200 to 600 nm, the semiconductor active layer 8 is made of amorphous silicon and has a thickness of about 20 to 200 nm, and the contact layer is made of impurity-doped amorphous silicon and has a thickness of about 10 to 100 nm. Deposited by (Plasma-Chemical Vapor Deposition) method. Thereafter, similarly to the first signal wiring layer 42, resist patterning is performed by photolithography. Thereafter, the semiconductor active region is formed by selectively dry-etching the semiconductor active layer 8 and the contact layer made of the doped semiconductor with respect to the insulating film 15. Since the insulating film 15 and the first signal wiring layer 42 are not laminated at the end of the radiation detector 10 provided with the data pad 50, the manufacturing process of the data pad 50 shown in FIG. Not shown.

  Next, as shown in FIG. 6A, the signal wiring 3 is formed as a second signal wiring layer 52 on the substrate 1 at the upper layer of the insulating film 15 and the semiconductor active layer 8 and at the end of the radiation detector 10. Then, the source electrode 9 and the drain electrode 13 are formed. Similar to the first signal wiring layer 42, the second signal wiring layer 52 is a laminated film with a low-resistance metal such as Al or Al alloy or a barrier metal layer made of a refractory metal, or a refractory metal such as Mo. It consists of a single film layer, and the film thickness is around 100 to 600 nm. Similarly to the first signal wiring layer 42, patterning is performed by a photolithography technique, and the metal film is patterned by a wet etching method using an etchant for Al or a dry etching method. The contact layer and part of the semiconductor active layer 8 are removed by dry etching to form a channel region of the TFT switch 4.

  Next, as shown in FIG. 6A, the TFT protective layer 30 and the interlayer insulating film 12 are sequentially formed on the substrate 1 and the second signal wiring layer 52 formed as described above. Note that the interlayer insulating film 12 is not shown in FIG. 6A because it is not laminated at the end of the radiation detector 10 provided with the data pad 50. The TFT protective layer 30 and the interlayer insulating film 12 are formed of a single inorganic material, formed by stacking a protective insulating film made of an inorganic material and an interlayer insulating film made of an organic material, or a single interlayer insulating film made of an organic material. May form. In the present embodiment, for example, a TFT protective film layer 30 is formed by CVD film formation, a photosensitive interlayer insulating film 12 material that is a coating system material is applied, prebaked, passed through exposure and development steps, and then baked. To form each layer. Next, the TFT protective film layer 30 is patterned by photolithography.

  Further, in the radiation detector 10, the lower electrode 11, the semiconductor layer 21, and the upper electrode 22 are formed on the interlayer insulating film 12 and the TFT protective layer 30. These layers are not shown in FIG. 6 because they are not stacked on the end of the radiation detector 10 provided with the data pad 50. For the lower electrode, an Al-based metal material is deposited by sputtering to have a film thickness of about 20 to 500 nm, patterned by photolithography, and wet etching using a metal etchant or the like. It is formed by patterning using an etching method. When the semiconductor layer 21 that is a photoelectric conversion layer is an organic photoelectric conversion material, it may be formed by, for example, a CVD method. The film thickness is preferably 30 nm or more and 300 nm or less, more preferably 50 nm or more and 250 nm or less, and particularly preferably 80 nm or more and 200 nm or less. In the case of an inorganic photoelectric conversion material, the semiconductor layer 21 is formed by depositing the n + layer 21A, the i layer 21B, and the p + layer 21C in order from the lower layer by the CVD method. The film thicknesses are, for example, n + layer 10 to 500 nm, i layer 0.2 to 2 μm, and p + layer 10 to 500 nm, respectively. The semiconductor layer 21 is completed by sequentially laminating each layer, patterning the semiconductor layer 21 by photolithography, and selectively etching with the lower interlayer insulating film 12 by dry etching or wet etching. The n + layer 21A, the i layer 21B, and the p + layer 21C are not stacked in this order, but the p + layer 21C, the i layer 21B, and the n + layer 21A may be stacked in this order to form a PIN diode. The upper electrode 22 is formed by depositing a transparent electrode material such as ITO so as to have a film thickness of about 20 to 200 nm by a sputtering method, patterning by a photolithography technique, a wet etching method using an etchant for ITO, or the like. It is formed by patterning using a dry etch method.

  Next, as shown in FIG. 6B, an interlayer insulating film 23 made of a SiNx film is deposited. Here, SiNx formed by CVD is described as an example, but any insulating material can be applied and is not limited to SiNx.

  Further, in order to form the data pad 50, as shown in FIG. 6C, a contact hole 36 penetrating the interlayer insulating film 23 and the TFT protective layer 30 is formed by a wet etching method for an insulating film or a dry etching method. Batch formation.

  Further, as shown in FIG. 6D, a metal material such as an Al-based material or ITO is deposited on the interlayer insulating film 23 by a sputtering method, and patterning is performed by a photolithography technique, and a metal etchant or the like. The data pad 50 is formed by patterning using a wet etching method or a dry etching method.

  Further, as shown in FIG. 6E, the data pad 50 is masked, and the protective layer 34, which is an insulating film, is formed by, for example, CVD film formation so as to have an opening in a region where the data pad 50 is formed. Form. In the radiation detector 10 of the present embodiment, the data pad 50 is formed in this way.

  Meanwhile, a data pad in a conventional radiation detector will be described here. FIG. 9 shows a cross-sectional view of an end portion of a radiation detector 1000 provided with a conventional data pad 500.

As shown in FIG. 9, in the conventional radiation detector 1000, an insulating film 15 is formed on the substrate 1. A second signal wiring layer 52 (a wiring layer including the signal wiring 3, the source electrode 9, and the drain electrode 13) is formed on the insulating film 15, and the insulating film 15 and the second signal wiring layer 52 are formed. A TFT protective layer 30 is formed on the top. Further, an opening is formed in an upper layer near the end of the second signal wiring layer 52, and the TFT protective layer is covered so as to cover the opening. A lower electrode 11 serving as a relay electrode is formed on 30. Further, an interlayer insulating film 23 is formed on the TFT protective layer 30 and the lower electrode 11. Further, a protective layer 34 having an opening in a region where the data pad 500 is formed is formed on the interlayer insulating film 23. A data pad 500 is formed in the opening of the protective layer 34 on the interlayer insulating film 23, and the data pad 500 and the lower electrode 11 are electrically connected to each other through a contact hole 501 that penetrates the interlayer insulating film 23. Connected directly. Thus, in the conventional radiation detector 1000, the data pad 500 and the second signal wiring layer 52 are connected via the lower electrode 11.

  A manufacturing process of the data pad 500 of the conventional radiation detector 1000 will be described with reference to FIG. In addition, about the affirmation similar to the manufacturing process of the data pad 50 of the radiation detector 10 of this Embodiment shown in FIG. 6 mentioned above, that effect is described and detailed description is abbreviate | omitted.

  First, FIG. 10A1 corresponds to the above-described FIG. 6A, and the second signal wiring layer 52 and the TFT protective layer 30 are formed on the substrate 1. Further, as shown in FIG. 10A2, the TFT protective layer 30 is etched to form a contact hole. In FIG. 10A3, the lower electrode 11 serving as a relay electrode is formed while filling the contact hole. To do.

  Further, FIG. 10B corresponds to FIG. 6B described above. Here, an interlayer insulating film 23 is formed on the TFT protective layer 30 and the lower electrode 11. Further, FIG. 10C corresponds to the above-described FIG. 6C, but here, only the interlayer insulating film 23 is etched to reach the lower electrode 11 to form a contact hole. Next, FIG. 10D corresponds to FIG. 6D described above, and the data pad 500 is formed on the interlayer insulating film 23 while filling the contact holes formed in the interlayer insulating film 23. Further, FIG. 10E corresponds to the above-described FIG. 6E, and the data pad 500 is formed in the conventional radiation detector 1000 by forming the protective layer 34.

  As described above, in the data pad 50 of this embodiment, the interlayer insulating film 23 and the TFT protective layer 30 are collectively etched to form the contact hole 36, and the data pad 50 is formed while filling the contact hole 36. Thus, the second signal wiring layer 52 is directly connected. That is, the data pad 50 and the second signal wiring layer 52 are connected without passing through the lower electrode 11.

  On the other hand, in the conventional data pad 500, the data pad 50 and the second signal wiring layer 52 are connected via the lower electrode 11.

  When forming the semiconductor layer 21 described above, the lower electrode 11 is difficult to control the etching conditions because the film thickness of the semiconductor layer 21 is thick, and may be damaged when the semiconductor layer 21 is etched. On the other hand, the data pad 500 (in this embodiment, the data pad 50) is formed in the opening of the protective layer 34, and its surface is not covered with the protective layer 34, so that moisture or other moisture can easily enter. It has become. When the lower electrode 11 is provided in the opening as in the conventional data pad 500, the invaded moisture reaches the damaged lower electrode 11 and is electrochemical corrosion (corrosion). Touch may occur. However, in the data pad 50 of the present embodiment, the data pad 50 and the second signal wiring layer 52 are connected without the lower electrode 11, and the lower electrode 11 is not provided in the opening of the protective layer 34. Therefore, the lower electrode 11 is not damaged during the etching, and even when moisture enters, there is little possibility that the above-described corrosion occurs. Therefore, in the present embodiment, corrosion of the lower electrode 11 can be suppressed.

  Next, the gate pad 40 of the present embodiment will be described. FIG. 7 is a plan view showing an example of the structure of the end of the radiation detector 10 in which the gate pad 40 according to the present embodiment is arranged. FIG. 8 shows a cross-sectional view of an example of an end portion of the radiation detector 10 on which the gate pad 40 is arranged.

  As shown in FIG. 8, the first signal wiring layer 42 (wiring layer including the gate electrode 2 and the scanning wiring 101) and the insulating film 15 are formed on the substrate 1. Further, a second signal wiring layer 52 (a wiring layer including the signal wiring 3, the source electrode 9, and the drain electrode 13) is formed on the insulating film 15, and the first signal wiring layer 42 and the second signal are formed. The wiring layer 52 is electrically connected through the contact hole 37. Further, the TFT protective layer 30 is formed on the second signal wiring layer 52 and the insulating film 15.

  In addition, an interlayer insulating film 23 is formed on the TFT protective layer 30 at the end of the radiation detector 10 where the gate pad 40 is provided. Further, a protective layer 34 having an opening in the region where the gate pad 40 is formed is formed on the interlayer insulating film 23. A gate pad 40 is formed in the opening of the protective layer 34 on the interlayer insulating film 23, and the gate pad 40 and the second signal wiring layer 52 penetrate the interlayer insulating film 23 and the TFT protective layer 30. The contact hole 38 is electrically connected directly.

  Since the manufacturing process of the gate pad 40 is substantially the same as the manufacturing process of the data pad 50 of the above-described embodiment, description thereof is omitted here. Even when the gate pad 40 is manufactured, the TFT protective layer 30 and the interlayer insulating film 23 are collectively etched to form a contact hole, and the gate pad 40 is formed while filling the contact hole. The first signal wiring layer 42 and the gate pad 40 are electrically connected via the second signal wiring layer 52 without passing through the electrode 11.

  On the other hand, the gate pad in the conventional radiation detector will be described here. FIG. 11 shows a cross-sectional view of the end of the radiation detector 1000 provided with the data pad 500.

As shown in FIG. 11, in the conventional radiation detector 1000, the first signal wiring layer 42 is formed on the substrate 1. An insulating film 15 is formed on the first signal wiring layer 42 and the substrate 1. A second signal contact hole is formed in the insulating film 15, and a wiring layer 52 (a wiring layer including the signal wiring 3, the source electrode 9, and the drain electrode 13) is formed on the insulating film 15. Has been. A TFT protective layer 30 is formed on the insulating film 15 and the second signal wiring layer 52. An opening is formed in the TFT protective layer 30 up to the second signal wiring layer 52. A lower electrode 11 serving as a relay electrode is formed on the TFT protective layer 30 so as to cover the opening. Further, an interlayer insulating film 23 is formed on the lower electrode 11 and the TFT protective layer 30. Further, a protective layer 34 having an opening in a region where the gate pad 400 is formed is formed on the interlayer insulating film 23. A gate pad 400 is formed in the opening of the protective layer 34 on the interlayer insulating film 23, and the gate pad 400 and the lower electrode 11 are electrically connected to each other through a contact hole 401 that penetrates the interlayer insulating film 23. Connected directly. Thus, in the conventional radiation detector 1000, the gate pad 400 and the second signal wiring layer 52 are connected via the lower electrode 11.

  As described above, in the gate pad 40 of the present embodiment, the interlayer insulating film 23 and the TFT protective layer 30 are collectively etched to form the contact hole 38, and the gate pad 40 is formed while filling the contact hole 38. Thus, the second signal wiring layer 52 is connected to the first signal wiring layer 42. That is, the gate pad 40 and the first signal wiring layer 42 are connected without passing through the lower electrode 11.

  On the other hand, in the conventional gate pad 400, the gate pad 400 and the second signal wiring layer 52 are connected via the lower electrode 11. Therefore, since the lower electrode 11 is provided in the opening of the protective layer 34 in the data pad 50 as described above, the lower electrode 11 may be corroded. On the other hand, in the gate pad 40 of the present embodiment, since the lower electrode 11 is not provided in the opening of the protective layer 34, the lower electrode 11 is not damaged during the etching, and even when moisture enters, the lower electrode 11 is not damaged. Is less likely to cause corrosion. Therefore, in the present embodiment, corrosion of the lower electrode 11 can be suppressed.

  As described above, in the radiographic imaging device 100 of the present embodiment, the gate pad 40 and the data pad 50 are formed while filling the contact hole in which the interlayer insulating film 23 and the TFT protective layer 30 are collectively etched. Therefore, the data pad 50 and the second signal wiring layer 52 are connected without passing through the lower electrode 11, and the gate pad 40 and the first signal wiring layer 42 are connected. Therefore, the lower electrode 11 is not provided in the opening of the protective layer 34, and even when moisture enters, there is little possibility of corrosion, and the corrosion of the lower electrode 11 can be suppressed.

  The configurations and operations of the radiographic imaging device 100, the radiation detector 10, the gate pad 40, the data pad 50, and the like described in the present embodiment are examples, and the lower electrode is provided below the opening of the protective layer 34. 11, the data pad 50 and the second signal wiring layer 52 are connected to each other without intervening 11, and the gate pad 40 and the first signal wiring layer 42 are connected to each other without departing from the gist of the present invention. Needless to say, it can be changed accordingly.

  In the present embodiment, the TFT switch 4 is described as having a bottom gate structure in which a gate electrode is disposed below the gate insulating film and an active layer is formed above the gate insulating film. However, the present invention is not limited thereto. Needless to say, the present invention can be applied to an external connection terminal having another TFT structure such as a top gate structure in which a gate electrode is disposed above the gate insulating film and an active layer is formed below the gate insulating film.

  Moreover, in this Embodiment, the radiation of this invention is not specifically limited, X-ray, a gamma ray, etc. can be applied.

  In the present embodiment, the gate pad 40 and the data pad 50 which are external connection terminals of the radiation detector 10 have been described. However, the present invention is not limited to this, and external connection for connecting signal wirings of other semiconductor elements to the outside. Needless to say, the present invention can be applied to terminals.

4 TFT switch 10 Radiation detector 20 Pixel 40 Gate pad 42 First signal wiring layer 50 Data pad 52 Second signal wiring layer 100 Radiation imaging apparatus

Claims (4)

A photoelectric conversion layer that generates charges according to the received light;
A lower electrode for collecting charges generated in the photoelectric conversion layer;
A switching element that reads and outputs the charge collected by the lower electrode in accordance with a control signal;
A wiring layer for forming at least one of a signal wiring for outputting the electric charge read by the switching element and a control wiring for supplying the control signal to the switching element;
An external connection terminal for connecting the wiring layer to the outside without being connected via the lower electrode;
A semiconductor device comprising: A bias wiring for applying a bias voltage to the photoelectric conversion layer on the photoelectric conversion layer formed on the wiring layer;
The semiconductor device according to claim 1, wherein the external connection terminal is in the same layer as the bias wiring. A wavelength conversion layer that converts irradiated radiation into light;
The semiconductor element according to claim 1 or 2, wherein the light converted by the wavelength conversion layer is irradiated;
Radiation detector equipped with. Forming a wiring layer on the substrate;
Forming a first insulating film on the wiring layer;
Forming a photoelectric conversion layer on the first insulating film;
Forming a second insulating film on the photoelectric conversion layer;
Etching the first insulating film and the second insulating film to collectively form contact holes penetrating the first insulating film and the second insulating film;
Forming an external connection terminal on the second insulating film to fill the contact hole and connect the wiring layer to the outside;
The manufacturing method of the semiconductor element of the said Claim 1 or the said Claim 2 provided with these.

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