JP2015092518A - Semiconductor device, radiation detector, and manufacturing method of semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor element in which corrosion of a wiring layer is prevented even when moisture proofing of an external connection terminal is insufficient, a radiation detector, and manufacturing method of the semiconductor element.SOLUTION: In a connection section 62, an oxide conductor layer 54 is arranged adjacent (on or beneath) to a second wiring layer 44. An insulation film 60 is formed on the second wiring layer 44 and the oxide conductor layer 54. An external connection terminal 50 arranged in an opening of a protection layer 34 formed on the insulation film 60 and the oxide conductor layer 54 are electrically connected via a contact hole 52. The second wiring layer 44 does not come into direct contact with the contact hole 52 and the external connection terminal 60, but is electrically connected with them via the oxide conductor layer 54.

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.

  In a semiconductor element such as a radiation detector used in a radiographic imaging apparatus, a connection portion for connecting a wiring layer made of metal to an external electronic member is provided. For example, in the case of a radiation detector, a plurality of control wirings for supplying a control signal for turning on / off a switching element provided for reading charges from each pixel, and charges read from each pixel Each of the output signal wirings is electrically connected to an external circuit or the like via an external connection terminal (pad) provided in the connection portion.

  In such a connection portion of a semiconductor element, an oxide conductor such as ITO (Indium Tin Oxide) that is strong against outside air (humidity) such as humidity is generally used from the viewpoint of corrosion resistance (for example, Patent Document 1 and Patent Document). 2).

JP 2004-333642 A JP 2005-175204 A

  In general, a metal such as Al is used for the wiring that contacts the oxide conductor in the connection portion, but there is a problem that corrosion occurs due to a reference potential difference between ITO and Al. In order to avoid this problem, a method of covering the upper layer of Al with a barrier metal such as Mo is generally used. However, a barrier metal such as Mo is vulnerable to humidity, and ITO pinholes and cracks used as external connection terminals are used. There has been a problem in that corrosion occurs due to the humidity of the outside air that has entered through.

  In particular, the contact hole between the ITO and the metal layer has a problem that cracks and pinholes are likely to occur in the ITO due to the taper shape and the surface state of the metal layer, and cannot be sufficiently covered.

  In order to avoid these problems, terminal corrosion countermeasures are generally taken. For example, a technique as shown in FIG. 16 is used. In the connection portion 1062 of the conventional semiconductor element 1000 shown in FIG. 16, an external connection terminal 1050 to which an external electronic member is connected is provided in an opening portion of a protective layer 1034 provided on the insulating layer 1023. The external connection terminal 1050 and the wiring layer 1044 are connected to each other through a metal layer 1070, and the moisture-proof material 1072 prevents external air (humidity) from entering between the external connection terminal 1050 and the protective layer 1034. The cover by is provided.

  However, when pinholes or the like occur in the moisture-proof material 1072, there is a further problem that moisture-proofing becomes insufficient and corrosion occurs. When corrosion occurs, corrosion develops in the metal of the same layer, which may cause quality problems such as disconnection.

  The present invention has been made to solve the above problems, and can suppress corrosion of a wiring layer even when moisture-proofing of external connection terminals is not sufficient, a semiconductor element, a radiation detector, and a semiconductor An object is to provide a method for manufacturing an element.

  In order to achieve the above object, a semiconductor element of the present invention includes a wiring layer formed under an insulating film, and an oxide conductor formed under the insulating film by an oxide conductor and connected to the wiring layer. A contact portion formed in the contact hole penetrating the insulating film by the oxide conductor, and formed on the insulating film by the oxide conductor, and connected to the oxide conductor layer by the contact portion And an external connection terminal for connecting the wiring layer to the outside via the oxide conductor layer.

  The wiring layer of the semiconductor element of the present invention is preferably formed in an area other than the contact area provided with the contact hole.

  In addition, the oxide conductor layer of the semiconductor element of the present invention may be provided on the wiring layer.

  Further, the oxide conductor layer of the semiconductor element of the present invention may be provided under the wiring layer.

  The wiring layer of the semiconductor element of the present invention preferably has an opening in a contact area provided with the contact hole.

  In the semiconductor element of the present invention, it is preferable that the contact hole having a smaller diameter than the opening is provided so as to penetrate the opening of the wiring layer.

  Further, the external connection terminal of the semiconductor element of the present invention may be formed in an opening of a protective film formed on the insulating film.

  The wiring layer of the semiconductor element of the present invention is preferably formed in an area other than the lower layer of the opening of the protective film.

  The radiation detector of the present invention includes at least one of a direct conversion layer that generates charges according to the irradiated radiation and an indirect conversion layer that converts the irradiated radiation into light and generates charges according to the converted light. And a switching element that reads and outputs the charge generated in the conversion layer according to a control signal, and the wiring layer is a signal wiring to which the charge read by the switching element is output, And a semiconductor element of the present invention forming at least one of control wirings for supplying the control signal to the switching element.

  The method for manufacturing a semiconductor device of the present invention includes a step of forming a wiring layer on a substrate, a step of forming an oxide conductor layer so as to be connected to the wiring layer, the wiring layer, and the oxide conductor layer. Forming an insulating film thereon; forming a contact hole penetrating the insulating film to reach the oxide conductor layer; and filling the contact hole with an oxide conductor to form a contact portion; An external connection terminal for connecting the wiring layer to the outside through the oxide conductor layer is connected to the oxide film by the oxide conductor and to the oxide conductor layer by the contact portion. And a step of forming as described above.

  Even when the moisture resistance of the external connection terminal is not sufficient, the effect that the corrosion of the wiring layer can be suppressed is obtained.

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. 3 is a cross-sectional view of an example of a connection unit according to Embodiment 1. FIG. FIG. 5 is a plan view illustrating an example of an external connection terminal according to the first embodiment illustrated in FIG. 4. FIG. 6 is an explanatory diagram illustrating a manufacturing process of a connection portion (external connection terminal) according to the first embodiment. 6 is a cross-sectional view of an example of a connection portion according to Embodiment 2. FIG. It is a top view which shows an example of the external connection terminal which concerns on Example 2 shown in FIG. FIG. 10 is an explanatory diagram illustrating a manufacturing process of a connection portion (external connection terminal) according to a second embodiment. 10 is a cross-sectional view of an example of a connection part according to Embodiment 3. FIG. FIG. 11 is a plan view illustrating an example of an external connection terminal according to the third embodiment illustrated in FIG. 10. FIG. 10 is an explanatory diagram illustrating a manufacturing process of a connection portion (external connection terminal) according to a third embodiment. 10 is a cross-sectional view of an example of a connection unit according to Example 4. FIG. It is a top view which shows an example of the external connection terminal which concerns on Example 4 shown in FIG. FIG. 10 is an explanatory diagram illustrating a manufacturing process of a connection portion (external connection terminal) according to a fourth embodiment. It is sectional drawing of an example of the connection part in the conventional radiation detector.

  Hereinafter, an example of the present embodiment will be described with reference to the drawings. In this embodiment, as an example, a case where the semiconductor element of the present invention is applied to a radiation detector of a radiographic imaging apparatus will be described.

  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. 3), the scanning wiring 101 which is a plurality of control wirings for turning on / off the TFT switch 4 and the charges 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 </ b> A that is an external connection terminal 50. Further, a scan signal control for outputting a control signal for turning on / off the TFT switch 4 to each scan line 101 to each scan line 101 of the radiation detector 10 via a gate pad 50B which is an external connection terminal 50. A circuit 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), ROM and RAM, 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 pixel 20 of the present embodiment 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 shown 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 non-alkali glass or the like. 2 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 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 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 insulating film 15 on the gate electrode 2, 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 wiring layer 44”) is a laminate mainly composed of Al or Cu, or Al or Cu. The film is formed using, but 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, a TFT protective film layer 30 is provided on almost the entire area (substantially the entire area) where the pixels 20 on the substrate 1 are provided so as to cover the second wiring layer 44. Is formed. The TFT protective film layer 30 is made of, for example, SiN _x 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 a p + layer, an i layer, and an n + layer (p + amorphous silicon, amorphous silicon, n + amorphous silicon) are stacked is adopted as the semiconductor layer 21, and the p + layer 21A is formed from the lower layer. , I layer 21B and n + 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 p + layer 21A and the n + 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, an 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. 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 planarizing layer 32 is an insulating layer, and is formed of an organic material with a thickness of 1 to 6 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 external connection terminal 50 of the present embodiment will be described with specific examples. In the radiation detector 10 of the present embodiment, when the external connection terminal 50 is the data pad 50A, the second wiring layer 44 formed on the substrate 1 (the substrate 1 and the insulating film 15) is the data pad 50A. It is connected to the. When the external connection terminal 50 is the gate pad 50B, the first wiring layer 42 formed on the substrate 1 is connected to the second wiring layer 44 through the contact hole, and the first wiring layer 42 is The second wiring layer 44 is connected to the gate pad 50B. That is, in this embodiment, in both the data pad 50A and the gate pad 50B, the second wiring layer 44 is connected to an external electronic member (circuit, device) via the external connection terminal 50 (data pad 50A and gate pad 50B). Etc.). In the following embodiments, the second wiring layer 44 is connected to an external electronic member via the external connection terminal 50 (data pad 50A and gate pad 50B) (connection portion 62, see FIGS. 4 to 15). Will be described in detail.

Example 1
FIG. 4 shows a cross-sectional view of an example of the connecting portion 62 according to the present embodiment. FIG. 5 shows a plan view of an example of the connecting portion 62.

  As shown in FIG. 4, a second wiring layer 44 (a wiring layer including the signal wiring 3, the source electrode 9, and the drain electrode 13) is formed on the substrate 1. An oxide conductor layer 54 made of an oxide conductor is directly formed on the second wiring layer 44. The oxide conductor layer 54 is preferably a transparent conductor, for example, a conductor having high light transmittance such as ITO or IZO (zinc oxide indium) is preferable.

  In this embodiment, as shown in FIG. 5, the oxide conductor layer 54 is formed on the second wiring layer 44 with a size equal to or smaller than the size of the second wiring layer 44 in the connection portion 62.

  A TFT protective layer 30 and an interlayer insulating film 23 are formed on the substrate 1, the second wiring layer 44, and the oxide conductor layer 54. Since the interlayer insulating film 23 and the TFT protective layer 30 are substantially the same as described above, they are collectively referred to as the insulating film 60. Similarly, in the following embodiments, the interlayer insulating film 23 and the TFT protective layer 30 are collectively referred to as an insulating film 60.

  A protective layer 34 is formed on the insulating film 60 so as to have an opening in a region where the external connection terminal 50 is formed. An external connection terminal 50 is formed in the opening of the protective layer 34 on the insulating film 60. The external connection terminal 50 and the oxide conductor layer 54 are electrically connected by a contact hole 52 that penetrates the insulating film 60. Connected.

  Next, a manufacturing process of the external connection terminal 50 of the present example in the radiation detector 10 of the present embodiment will be described with reference to FIG. FIG. 6 shows the connection portion 62.

In the radiation detector 10, since the first wiring layer 42 is not provided in the connection portion 62, it is not illustrated in FIG. 6, but first, the gate electrode 2, the scanning is formed on the substrate 1 as the first wiring layer 42. A wiring 101 is formed. The first wiring layer 42 is composed of a laminated film with a low-resistance metal such as Al, Al alloy, Cu, Cu alloy, or a barrier metal layer made of a refractory metal. Are deposited on the substrate 1. Thereafter, the resist film is patterned by photolithography. Thereafter, the metal film is patterned by a wet etch method using a metal etchant or a dry etch method. Thereafter, the first 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 wiring layer 42. The insulating film 15 is made of SiN _x 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. The contact layer is made of doped amorphous silicon and has a thickness of about 10 to 100 nm. It deposits by CVD (Plasma-Chemical Vapor Deposition) method. Thereafter, similarly to the first wiring layer 42, resist patterning is performed by a photolithography technique. 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.

  Next, as illustrated in FIG. 6A, the signal wiring 3, the source electrode 9, and the drain electrode 13 are formed as the second wiring layer 44. In the connection portion 62, the second wiring layer 44 is formed on the substrate 1 or the insulating film 15 provided on the substrate 1. Similar to the first wiring layer 42, the second wiring layer 44 is a laminated film with a low-resistance metal such as Al, Al alloy, Cu, Cu alloy or a barrier metal layer made of a refractory metal, or Mo. It consists of a refractory metal film single layer, and the film thickness is around 100 to 600 nm. Similar to the first wiring layer 42, patterning is performed by a photolithography technique, and the metal film is patterned by a wet etch method using a metal etchant or a dry etch method.

  Further, in the pixel 20 of the radiation detector 10, a part of the contact layer and the semiconductor active layer 8 is removed by dry etching to form a channel region of the TFT switch 4.

  Next, as illustrated in FIG. 6B, the oxide conductor layer 54 is formed on the second wiring layer 44 of the connection portion 62. An oxide conductor material such as ITO is deposited by a sputtering method and patterned to have the shape shown in FIG. 5 by a photolithography technique, and an oxide is formed by a wet etching method using an etchant or a dry etching method. A conductor layer 54 is formed. The thickness of the oxide conductor layer 54 is preferably 10 μm to 100 μm.

  Next, as shown in FIG. 6C, the TFT protective layer 30 and the interlayer insulating film 23 are formed on the substrate 1 and the second wiring layer 44 and the oxide conductor layer 54 formed as described above. Insulating films 60 are formed in sequence.

  In the radiation detector 10 of the present embodiment, first, the TFT protective layer 30 and the interlayer insulating film 12 are sequentially formed. In addition, in the connection part 62, since the interlayer insulation film 12 is not provided, illustration is abbreviate | omitted in FIG. The interlayer insulating film 12 and the TFT protective layer 30 are formed of a single inorganic material, formed by stacking the TFT protective layer 30 made of an inorganic material and the interlayer insulating film 12 made of an organic material, or a single insulating film made of an organic material. It may be formed by layers. 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.

  Further, since none of the radiation detectors 10 of the present embodiment is provided in the connection portion 62, the lower portion is not formed on the interlayer insulating film 12 and the TFT protective layer 30 although not shown in FIG. The electrode 11, the semiconductor layer 21, and the upper electrode 22 are formed. For the lower electrode, a conductive material such as Al, Mo, or ITO is deposited by a sputtering method so that the film thickness is about 20 to 500 nm, patterned by a photolithography technique, and using a metal etchant or the like. It is formed by patterning using a wet etch method or a dry etch 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 p + layer 21A, the i layer 21B, and the n + 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. Note that the n + layer 21C, the i layer 21B, and the p + layer 21A may be stacked in this order instead of the p + layer 21A, the i layer 21B, and the n + layer 21C, and the NIP diode may be used. 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. Further, it may be a MIS diode.

Next, an interlayer insulating film 23 made of a SiN _x film is deposited on the interlayer insulating film 12 and the semiconductor layer 21. Here, the SiN _x film formed by CVD is described as an example, but any insulating material can be applied and is not limited to SiN _x . In this way, an insulating film 60 is formed as shown in FIG.

  Further, as shown in FIG. 6C, a contact hole 52 that penetrates the insulating film 60 and reaches the oxide conductor layer 54 is formed in the contact area by a wet etching method or a dry etching method for the insulating film. .

  Next, as shown in FIG. 6D, an oxide conductor material such as ITO is deposited on the insulating film 60 while filling the contact holes 52 by sputtering, and patterning is performed by photolithography. The external connection terminals 50 are formed by patterning using a wet etching method using an etchant or the like or a dry etching method.

  Next, as shown in FIG. 6E, the external connection terminal 50 is masked, and the protective layer 34, which is an insulating film, is provided in the region of the connection portion 62 where the external connection terminal 50 is formed. Is formed by, for example, CVD film formation. In the radiation detector 10 of the present embodiment, the external connection terminal 50 is formed in this way.

  As described above, in the connection portion 62 of this embodiment, the oxide conductor layer 54 is formed on the second wiring layer 44, and the oxide conductor layer 54 and the external connection terminal 50 are connected via the contact hole 52. Are electrically connected. As a result, by covering the second wiring layer 44 with the oxide conductor layer 54, the pinholes and the like of the external connection terminals 50 can be covered. Therefore, in the radiation detector 10 to which the semiconductor element provided with the connection portion 62 of the present embodiment is applied, even if the external connection terminal 50 has a pinhole or the like and the moisture resistance is not sufficient, the second wiring layer 44 and the first wiring are provided. Corrosion of the layer 42 can be suppressed.

(Example 2)
FIG. 7 shows a cross-sectional view of an example of the connecting portion 62 according to the present embodiment. FIG. 8 shows a plan view of an example of the connecting portion 62. In addition, since Example 2 is substantially the same as Example 1, detailed description is abbreviate | omitted about the same part.

  As shown in FIG. 7, a second wiring layer 44 (a wiring layer including the signal wiring 3, the source electrode 9, and the drain electrode 13) is formed on the substrate 1. An oxide conductor layer 54 made of an oxide conductor is formed from the second wiring layer 44 to the substrate 1 so as to cover the end portion of the second wiring layer 44.

  An insulating film 60 (TFT protective layer 30 and interlayer insulating film 23) is formed on the substrate 1, the second wiring layer 44, and the oxide conductor layer 54. A protective layer 34 having an opening is formed on the insulating film 60. An external connection terminal 50 is formed in the opening of the protective layer 34, and the external connection terminal 50 and the oxide conductor layer 54 are electrically connected by a contact hole 52 that penetrates the insulating film 60. .

  In this embodiment, as shown in FIG. 8, the second wiring layer 44 is not provided below the external connection terminal 50, and the end portion of the second wiring layer 44 and the end portion of the external connection terminal 50 are provided. Are arranged so that there is a gap between them. In the present embodiment, as shown in FIG. 7, the second wiring layer 44 is provided below the protective layer 34, and is not provided below the opening of the protective layer 34. The oxide conductor layer 54 is provided from the second wiring layer 44 to the lower region of the external connection terminal 50 (contact area in which the contact hole 52 is provided).

  As shown in FIGS. 7 and 8, in this embodiment, the second wiring layer is provided in the contact area provided with the contact hole 52 where the external connection terminal 50 and the oxide conductor layer 54 are electrically connected. 44 is not provided.

  Next, the manufacturing process of the external connection terminal 50 of the present embodiment in the radiation detector 10 will be described with reference to FIG. Note that FIG. 9 shows the connection portion 62.

  In the radiation detector 10, the first wiring layer 42, the insulating film 15, the semiconductor active layer 8, the contact layer, and the semiconductor active region are first formed on the substrate 1 as in the first embodiment.

  Next, as shown in FIG. 9A, the signal wiring 3, the source electrode 9, and the drain electrode 13 are formed as the second wiring layer 44 in the same manner as in the first embodiment (see FIG. 6A). . Next, as illustrated in FIG. 9B, an oxide conductor layer 54 is formed in a region from the second wiring layer 44 of the connection portion 62 to the contact area on the substrate 1.

  Next, as shown in FIG. 9C, the insulating film 60 is formed on the substrate 1 and the second wiring layer 44 and the oxide conductor layer 54 formed as described above in the same manner as in the first embodiment. To do. Further, as shown in FIG. 9C, a contact hole 52 that penetrates the insulating film 60 and reaches the oxide conductor layer 54 is formed in the contact area. Next, as illustrated in FIG. 9D, the external connection terminal 50 is formed over the insulating film 60 while filling the contact hole 52. Next, as shown in FIG. 9E, the external connection terminal 50 is masked to form a protective layer 34 that is an insulating film having an opening.

  In the radiation detector 10 of the present embodiment, the external connection terminal 50 is formed in this way.

  As described above, in the connection portion 62 of the present embodiment, the oxide conductor layer 54 is formed from the second wiring layer 44 to the contact area on the substrate 1 so as to cover the end portion of the second wiring layer 44. The oxide conductor layer 54 and the external connection terminal 50 are electrically connected via the contact hole 52. Since the second wiring layer 44 is not provided in the contact area, even when outside air (humidity / moisture) or the like enters through a pinhole or the like of the external connection terminal 50, the second wiring layer 44 is prevented from reaching the second wiring layer 44. Can do. In the present embodiment, the second wiring layer 44 is provided below the protective layer 34 and is not provided below the opening of the protective layer 34, so that the outside air entering from the opening of the protective layer 34 is provided. Corrosion due to (humidity / moisture) can be suppressed. Therefore, in the radiation detector 10 to which the semiconductor element provided with the connection portion 62 of the present embodiment is applied, even if the external connection terminal 50 has a pinhole or the like and the moisture resistance is not sufficient, the second wiring layer 44 and the first wiring are provided. Corrosion of the layer 42 can be suppressed.

(Example 3)
FIG. 10 shows a cross-sectional view of an example of the connecting portion 62 according to the present embodiment. FIG. 11 shows a plan view of an example of the connecting portion 62. In addition, since Example 3 is substantially the same as Example 1 and Example 2, detailed description is abbreviate | omitted about the same part.

  As shown in FIG. 10, a second wiring layer 44 (a wiring layer including the signal wiring 3, the source electrode 9, and the drain electrode 13) and an oxide conductor layer 54 are formed on the substrate 1. In this embodiment, the oxide conductor layer 54 is provided below the second wiring layer 44 (between the substrate 1 and the second wiring layer 44).

  An insulating film 60 (TFT protective layer 30 and interlayer insulating film 23) is formed on the substrate 1, the second wiring layer 44, and the oxide conductor layer 54. A protective layer 34 having an opening is formed on the insulating film 60. An external connection terminal 50 is formed in the opening of the protective layer 34, and the external connection terminal 50 and the oxide conductor layer 54 are electrically connected by a contact hole 52 that penetrates the insulating film 60. .

  In this embodiment, as shown in FIG. 11, the second wiring layer 44 is not provided below the external connection terminal 50, and the end of the second wiring layer 44 and the end of the external connection terminal 50 are provided. Are arranged so that there is a gap between them. In the present embodiment, as shown in FIG. 10, the second wiring layer 44 is provided below the protective layer 34, and is not provided below the opening of the protective layer 34. The oxide conductor layer 54 is provided on the substrate 1 from below the second wiring layer 44 to a lower region of the external connection terminal 50 (contact area in which the contact hole 52 is provided).

  Thus, in the present embodiment, the second wiring layer 44 is not provided in the contact area where the contact hole 52 in which the external connection terminal 50 and the oxide conductor layer 54 are electrically connected is provided. .

  Next, the manufacturing process of the external connection terminal 50 of the present embodiment in the radiation detector 10 will be described with reference to FIG. In addition, in FIG. 12, it has shown about the connection part 62. FIG.

  In the radiation detector 10, the first wiring layer 42, the insulating film 15, the semiconductor active layer 8, the contact layer, and the semiconductor active region are first formed on the substrate 1 as in the first embodiment.

  Next, as illustrated in FIG. 12A, an oxide conductor layer 54 is formed in a region from the lower portion of the second wiring layer 44 on the substrate 1 to the contact area in the connection portion 62. Next, as shown in FIG. 12B, the signal wiring 3, the source electrode 9, and the drain electrode 13 are formed as the second wiring layer 44.

  Next, as shown in FIG. 12C, the insulating film 60 is formed on the substrate 1 and the second wiring layer 44 and the oxide conductor layer 54 formed as described above in the same manner as in the first embodiment. Form. Further, as shown in FIG. 12C, a contact hole 52 that penetrates the insulating film 60 and reaches the oxide conductor layer 54 is formed in the contact area. Next, as illustrated in FIG. 12D, the external connection terminal 50 is formed over the insulating film 60 while filling the contact hole 52. Next, as shown in FIG. 12E, the external connection terminal 50 is masked to form a protective layer 34 that is an insulating film having an opening.

  In the radiation detector 10 of the present embodiment, the external connection terminal 50 is formed in this way.

  As described above, in the connection portion 62 of this embodiment, the oxide conductor layer 54 is formed from the lower portion of the second wiring layer 44 to the contact area, and the oxide conductor layer 54 and the external connection terminal 50 are connected to the contact hole. It is electrically connected via 52. Since the second wiring layer 44 is not provided in the contact area, even when outside air (humidity / moisture) or the like enters through a pinhole or the like of the external connection terminal 50, the second wiring layer 44 is prevented from reaching the second wiring layer 44. Can do. In the present embodiment, the second wiring layer 44 is provided below the protective layer 34 and is not provided below the opening of the protective layer 34, so that the outside air entering from the opening of the protective layer 34 is provided. Corrosion due to (humidity / moisture) can be suppressed. Therefore, in the radiation detector 10 which is a semiconductor element provided with the connection portion 62 of the present embodiment, even if the external connection terminal 50 has a pinhole or the like and moisture resistance is not sufficient, the second wiring layer 44 and the first wiring layer. 42 corrosion can be suppressed.

Example 4
FIG. 13 shows a cross-sectional view of an example of the connecting portion 62 according to the present embodiment. FIG. 14 shows a plan view of an example of the connecting portion 62. In addition, since Example 4 is substantially the same as Example 1- Example 3, detailed description is abbreviate | omitted about the same part.

  As shown in FIG. 13, a second wiring layer 44 (a wiring layer including the signal wiring 3, the source electrode 9, and the drain electrode 13) and an oxide conductor layer 54 are formed on the substrate 1. In this embodiment, the oxide conductor layer 54 is provided below the second wiring layer 44 (between the substrate 1 and the second wiring layer 44). The second wiring layer 44 is provided so as to cover the oxide conductor layer 54, and has an opening 56 in a contact area where the contact hole 52 is provided.

  An insulating film 60 (TFT protective layer 30 and interlayer insulating film 23) is formed on the substrate 1, the second wiring layer 44, and the oxide conductor layer 54. A protective layer 34 having an opening is formed on the insulating film 60. An external connection terminal 50 is formed in the opening of the protective layer 34, and the external connection terminal 50 and the oxide conductor layer 54 are contacts penetrating the opening 56 of the insulating film 60 and the second wiring layer 44. The holes 52 are electrically connected.

  In this embodiment, as shown in FIG. 14, the opening 56 of the second wiring layer 44 is provided with a diameter larger than that of the contact hole 52 (opening of the insulating film 60). The shape of the opening 56 is not limited to a rectangle as shown in FIG. 14 and may be a circle or other polygons, and is not particularly limited. Moreover, as shown in FIG. 14, the shape of the contact hole 52 (opening of the insulating film 60) may be the same shape, and a different shape may be sufficient. In this embodiment, the opening 56 is provided. However, the opening 56 is not provided, but the second wiring layer 44 provided on the oxide conductor layer 54 is disconnected in the contact area. You may comprise.

  Thus, in the present embodiment, the second wiring layer 44 is not provided in the contact area where the contact hole 52 in which the external connection terminal 50 and the oxide conductor layer 54 are electrically connected is provided. .

  Next, the manufacturing process of the external connection terminal 50 of the present embodiment in the radiation detector 10 will be described with reference to FIG. Note that FIG. 15 shows the connection portion 62.

  In the radiation detector 10, the first wiring layer 42, the insulating film 15, the semiconductor active layer 8, the contact layer, and the semiconductor active region are first formed on the substrate 1 as in the first embodiment.

  Next, as shown in FIG. 15A, as in the third embodiment (see FIG. 12A), in the connection portion 62, a region extending from the lower portion of the second wiring layer 44 on the substrate 1 to the contact area. An oxide conductor layer 54 is formed. Next, as illustrated in FIG. 15B, the signal wiring 3, the source electrode 9, and the drain electrode 13 are formed as the second wiring layer 44. In the present embodiment, the second wiring layer 44 is formed so as to cover the oxide conductor layer 54 and to have the opening 56.

  Next, as shown in FIG. 15C, an insulating film 60 is formed on the substrate 1 and the second wiring layer 44 and the oxide conductor layer 54 formed as described above in the same manner as in the first embodiment. Form. Further, as shown in FIG. 15C, a contact hole 52 that penetrates the opening 56 of the second wiring layer 44 and the insulating film 60 and reaches the oxide conductor layer 54 is formed in the contact area. Next, as illustrated in FIG. 15D, the external connection terminal 50 is formed over the insulating film 60 while filling the contact hole 52. Next, as shown in FIG. 12E, the external connection terminal 50 is masked to form a protective layer 34 that is an insulating film having an opening.

  In the radiation detector 10 of the present embodiment, the external connection terminal 50 is formed in this way.

  As described above, in the connection portion 62 of this example, the second wiring layer 44 having the opening 56 is formed on the oxide conductor layer 54 provided in the contact area. The external connection terminal 50 is electrically connected through the contact hole 52 that penetrates the insulating film 60 and the opening 56 of the second wiring layer 44. The diameter of the opening 56 is larger than the diameter of the contact hole 52, and the second wiring layer 44 is covered with the insulating film 60 and is not in contact with the contact hole 52 and the oxide conductor layer 54. Even when outside air (humidity / moisture) or the like enters through 50 pinholes or the like, it can be prevented from reaching the second wiring layer 44. Therefore, in the radiation detector 10 to which the semiconductor element provided with the connection portion 62 of the present embodiment is applied, even if the external connection terminal 50 has a pinhole or the like and the moisture resistance is not sufficient, the second wiring layer 44 and the first wiring are provided. Corrosion of the layer 42 can be suppressed.

  As described above, in the connection portion 62 of the radiation detector 10 of the present exemplary embodiment, the oxide conductor layer 54 is provided adjacent to (upper or lower) the second wiring layer 44, and the second wiring An insulating film 60 is formed on the layer 44 and the oxide conductor layer 54. The external connection terminal 50 provided in the opening of the protective layer 34 provided on the insulating film 60 and the oxide conductor layer 54 are electrically connected by the contact hole 52, and the second wiring layer 44 is The contact hole 52 and the external connection terminal 50 are not in direct contact with each other but are electrically connected through the oxide conductor layer 54.

  Thereby, since the second wiring layer 44 is not in direct contact with the contact hole 52 and the external connection terminal 50, the pinhole of the external connection terminal 50 can be covered. Therefore, in the radiation detector 10 to which the semiconductor element provided with the connection portion 62 of the present embodiment is applied, even if the external connection terminal 50 has a pinhole or the like and the moisture resistance is not sufficient, the second wiring layer 44 and the first wiring are provided. Corrosion of the layer 42 can be suppressed.

  The configuration, manufacturing method, and the like of the radiographic imaging apparatus 100, the radiation detector 10, the external connection terminals 50 (data pad 50A and gate pad 50B) described in the present embodiment are examples, and the external connection terminals 50 and The oxide conductor layer 54 is electrically connected through the contact hole 52, and the first wiring layer 42 and the second wiring layer 44 are not in direct contact with the contact hole 52 and the external connection terminal 50, and are oxidized. It is electrically connected through the physical conductor layer 54, and the portion in contact with the contact hole 52 is formed of an oxide conductor that is resistant to corrosion. It goes without saying that it is possible.

  In the present embodiment, the radiation detector 10 having the bottom gate structure in which the TFT switch 4 has the gate electrode disposed below the gate insulating film and the active layer formed above the gate insulating film has been described. Not limited to this, it 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 on the upper side of the gate insulating film and an active layer is formed on the lower side of the gate insulating film. Nor.

  Further, in the present embodiment, the wiring layer in which the source electrode 9 and the drain electrode are formed and the signal wiring 3 are formed as the same layer, but the present invention is not limited to this, and another layer may be used.

 In the present embodiment, the first wiring layer 42 is connected to the external connection terminal 50 (oxide conductor layer 54) via the second wiring layer 44. However, the present invention is not limited to this. For example, each of the first wiring layer 42 and the second wiring layer 44 may be configured to be connected to the external connection terminal 50 by applying the present invention, or may be applied to one wiring layer by applying the present invention. You may comprise so that it may connect with the terminal 50. FIG. Further, for example, a separate layer connected to the external connection terminal 50 to which the present invention is applied is provided separately from the first wiring layer 42 and the second wiring layer 44, and the first wiring layer 42 and the second wiring layer 44 are provided via the separate layer. The two wiring layers 44 may be configured to be connected to external connection terminals. Note that a method for connecting the first wiring layer 42 and the second wiring layer 44 to the oxide conductor layer 54 is not particularly limited, but it is preferable to connect (form) them so that they can be handled as the same layer.

  In the present embodiment, the case where the present invention is applied to the radiation detector 10 of the indirect conversion type that converts the converted light into electric charges has been described. However, the present invention is not limited to this. For example, the present invention may be applied to a direct conversion type radiation detector using a material such as amorphous selenium that directly converts radiation into charges as a photoelectric conversion layer that absorbs radiation and converts it into charges.

  In this embodiment, the protective layer 34 is provided and the external connection terminal 50 is provided in the opening of the protective layer 34. However, the present invention is not limited to this. For example, it is preferable to provide the protective layer 34 as in this embodiment, but the protective layer 34 may not be provided.

  Moreover, in the radiographic imaging apparatus 100 (radiation detector 10) of this Embodiment, a radiation is not specifically limited, An X ray, a gamma ray, etc. can be applied.

  In the present embodiment, the case where the radiation detector 10 is applied as the external connection terminal 50 (the data pad 50A and the gate pad 50B) has been described in detail as a specific example. Needless to say, the present invention can be applied to external connection terminals for connecting wirings and electrodes to the outside.

DESCRIPTION OF SYMBOLS 10 Radiation detector 20 Pixel 42 1st wiring layer 44 2nd wiring layer 50 External connection terminal (50A data pad, 50B gate pad)
52 Contact hole 54 Oxide conductor layer 56 Opening 60 Insulating film 62 Connection 100 Radiation imaging apparatus

Claims (10)

A wiring layer formed under the insulating film;
An oxide conductor layer formed under the insulating film by an oxide conductor and connected to the wiring layer;
A contact portion formed in a contact hole penetrating the insulating film by an oxide conductor;
External connection for connecting the wiring layer to the outside through the oxide conductor layer, which is formed on the insulating film by the oxide conductor and connected to the oxide conductor layer by the contact portion A terminal,
A semiconductor device comprising:   The semiconductor element according to claim 1, wherein the wiring layer is formed in an area other than a contact area in which the contact hole is provided.   The semiconductor element according to claim 1, wherein the oxide conductor layer is provided on the wiring layer.   The semiconductor element according to claim 1, wherein the oxide conductor layer is provided under the wiring layer.   The semiconductor element according to claim 4, wherein the wiring layer has an opening in a contact area where the contact hole is provided.   The semiconductor element according to claim 5, wherein the contact hole having a diameter smaller than the opening is provided so as to penetrate the opening of the wiring layer.   The semiconductor device according to claim 1, wherein the external connection terminal is formed in an opening of a protective film formed on the insulating film.   The semiconductor element according to claim 7, wherein the wiring layer is formed in an area other than a lower layer of the opening of the protective film. A conversion layer that includes at least one of a direct conversion layer that generates a charge according to the irradiated radiation, and an indirect conversion layer that converts the irradiated radiation into light and generates a charge according to the converted light;
A switching element that reads out and outputs the charge generated in the conversion layer according to a control signal, and the wiring layer outputs a signal wiring to which the charge read out by the switching element is output; and the switching element The semiconductor element according to any one of claims 1 to 8, wherein at least one of control wirings for supplying a control signal is formed;
Radiation detector equipped with. Forming a wiring layer on the substrate;
Forming an oxide conductor layer to connect with the wiring layer;
Forming an insulating film on the wiring layer and the oxide conductor layer;
Forming a contact hole penetrating the insulating film and reaching the oxide conductor layer;
Filling the contact hole with an oxide conductor to form a contact portion;
An external connection terminal for connecting the wiring layer to the outside through the oxide conductor layer is connected to the oxide film by the oxide conductor and the oxide conductor layer by the contact portion. Forming the step,
A method for manufacturing a semiconductor device comprising:

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