JP6477910B2 - Display device and display device substrate - Google Patents

Description

  The present invention relates to a display device and a display device substrate including a light emitting layer including organic electroluminescence or LED, and more particularly to a display device having a touch sensing function and a display device substrate used for the display device.

  In recent years, the resolution of a liquid crystal display device or a display device in which light emitting elements are arranged in a matrix (an organic electroluminescence display device or an LED matrix display device) has been improved, and the thickness has been reduced. In addition, mobile devices such as smartphones and tablets that are equipped with a display device having a screen size of 5 inches or 8 inches and capable of realizing high image quality are commercially available. In particular, an organic electroluminescence display device (hereinafter referred to as organic EL) can contribute to the thinning of such a mobile device.

  In an organic EL display device, an organic EL substrate provided with a white organic EL and a counter substrate provided with a color filter for realizing color display and disposed opposite to the organic EL substrate may be used. In order to obtain higher image quality, for example, a red light emitting LED chip, a green light emitting LED chip, and a blue light emitting LED chip are mounted on a small light emitting unit, and a plurality of light emitting units are arranged in a matrix on an array substrate. LED matrix display devices are also being developed. As the LED, a blue light emitting diode with high luminous efficiency is known, and a white LED in which a green phosphor and a red phosphor are arranged on a blue LED chip may be used.

  In a display device having a light emitting layer including an organic EL (Organic Electroluminescence) or LED (Light Emitting Diode), it is formed of aluminum or silver in order to improve the brightness when the display device is viewed from the observer side. A lower electrode (light-reflective pixel electrode) is essential. When the display device is viewed from the viewer side, the lower electrode is an electrode at a far position, and the upper electrode is an electrode at a position closer to the viewer relative to the lower electrode. .

  Patent Document 1 describes a touch-sensitive display including a thinned encapsulation layer between an organic light emitting diode, a capacitive touch sensor electrode, and a control line that carries a touch sensor signal. Claim 2 of Patent Document 1 discloses a conductive grid covered with a black matrix. The control line is formed on the common substrate as shown in claim 9 of Patent Document 1. In Patent Document 1, a control line for carrying a touch sensor signal is provided on a substrate on which a pixel array is formed, as shown in FIGS. 10 and 39, paragraphs [0031] and [0032]. As described in paragraphs [0064] to [0066] of Patent Document 1, the line 640 carries a display control signal and a sensor drive signal. In order to perform pixel driving, time division multiplexing has been proposed. Details of the time division multiplex are not disclosed in Patent Document 1, but not only the time division drive technology but also the wiring structure in which the line 640 serves as both the display control and the sensor drive is complicated. Control using the wiring structure is complicated. The need to prevent interference with pixel drive during capacitive touch sensor capacitance operation is described in paragraph [0066] of US Pat.

  The line 640 is estimated as the control line, but is not clearly described in Patent Document 1. Further, it is not clearly described in the specification that the “common substrate” described in claim 9 in Patent Document 1 is specified as “common substrate”. Further, paragraph [0036] of Patent Document 1 describes that the touch sensor line is formed of a metal such as copper or gold. However, copper group elements such as copper, silver, and gold do not have practical adhesion to glass substrates and plastic films, and Patent Document 1 discloses adhesion to a metal substrate such as copper, silver, and gold. No practical technology has been proposed to improve the performance.

Patent Document 2 relates to a liquid crystal display device in which a touch sensor and a display device are integrated. Patent Document 2 discloses a technique for creating a touch screen on an array substrate using a bypass tunnel or the like.
In Patent Document 3, not only signal lines (gate lines and source lines) and pixel electrodes connected to polysilicon transistors, but also a sense area related to touch sensing, a drive-sense ground area, a bypass tunnel, and the like are arranged on the same array substrate. It is necessary to arrange on top. For this reason, in Patent Document 3, the array structure is extremely complicated, the parasitic capacitance is likely to increase, and the load in the manufacturing process of the array substrate is large. Patent Document 3 discloses a technique for forming an electrode used in a display device such as an organic EL device. Paragraph [0008] of Patent Document 3 describes that the adhesiveness of a pure Ag film or an Ag alloy film is insufficient and lacks practicality.

Patent Document 4 discloses that an aluminum-containing metal layer is used as a lower electrode of an organic EL element.
In patent document 5, the black substrate provided with the touch sensing wiring which has the structure by which the copper containing layer was pinched | interposed by the indium containing layer on the black layer, and the manufacturing method of a black substrate are disclosed. However, Patent Document 5 does not consider a display device including a light emitting layer such as an organic EL or LED, and does not disclose a technical problem in a display device to which an array substrate including the light emitting layer is applied. Moreover, the structure which performs touch sensing with two sets of black wiring in the black board | substrate is not disclosed.

  Patent Document 6 discloses a touch panel in which a black layer and a metal layer are stacked as a wiring structure. However, a display device including a light emitting layer and an active element made of an oxide semiconductor is not disclosed. Furthermore, a configuration in which a copper alloy or a silver alloy is sandwiched between conductive metal oxides is not disclosed.

Japanese Patent No. 58644741 Japanese Patent No. 5,746,736 Japanese Unexamined Patent Publication No. 2014-120487 Japanese Unexamined Patent Publication No. 2006-76418 Japanese Patent No. 5807726 Japanese Unexamined Patent Publication No. 2013-129183

In a display device including a light emitting layer including an organic EL or LED, aluminum or an aluminum alloy is often used as a material for a reflective electrode (hereinafter sometimes referred to as a lower electrode). Similarly, it is common to use aluminum or an aluminum alloy as a material for an electrode or a wiring constituting a thin film transistor for driving a light emitting layer such as a light emitting diode or a material for a touch sensing wiring. However, aluminum and aluminum alloys are inferior in electrical conductivity compared to silver and silver alloys, and copper and copper alloys.
As a material for the pixel electrode (hereinafter sometimes referred to as a reflective electrode), silver or an alloy is excellent in terms of light reflectivity.
In addition, as described above, silver and silver alloys, and copper and copper alloys have poor adhesion to substrates and the like. Further, silver has a drawback that the electrical properties are adversely affected with respect to the constituent material located around the member made of silver by migration or diffusion.

  This invention is made | formed in view of said subject, Comprising: Silver, a silver alloy, copper, and a copper alloy are utilized for the electrode and wiring which comprise the display apparatus using organic EL or a light emitting diode, and further Provided are a display device and a display device substrate that realize a good touch sensing function and high image quality.

The display device according to the first aspect of the present invention is a display device, a light-reflective pixel electrode having a configuration in which a silver alloy layer in which calcium is added to silver is sandwiched between conductive metal oxide layers; An array substrate comprising: a light emitting layer that emits light at a driving voltage applied from the pixel electrode; and an active element that has a channel layer that is in contact with the gate insulating layer and is made of an oxide semiconductor and drives the light emitting layer. A transparent substrate having a first surface facing the array substrate and a second surface opposite to the first surface; and a first black layer in an observation direction from the second surface toward the first surface; A plurality of first touch sensing wires extending in parallel with each other so as to be aligned in the first direction on the second surface, and a second in the observation direction; The black layer and the second conductive layer Are arranged between the plurality of first touch sensing wires and the array substrate, and extend parallel to each other so as to be aligned in a second direction orthogonal to the first direction in plan view. A display device substrate comprising: a plurality of second touch sensing wirings; and a plurality of pixels defined by the plurality of first touch sensing wirings and the plurality of second touch sensing wirings in plan view; look including a control unit for performing touch sensing by detecting a change in capacitance between the touch sensing line and the second touch sensing lines, wherein the oxide semiconductor contains a metal oxide containing zinc A metal oxide containing at least one selected from the group consisting of gallium, indium, tin, aluminum, germanium, and cerium; Both include antimony, a metal oxide containing one of bismuth, wherein the gate insulating layer is formed of a composite oxide containing cerium oxide, the active element is a thin film transistor having a top gate structure .

  In the display device according to the first aspect of the present invention, the first touch sensing wiring and the second touch sensing wiring are formed on the second surface, and the first touch sensing wiring and the second touch sensing are formed. An insulating layer may be provided between the wiring and the first touch sensing wiring and the second touch sensing wiring may be electrically insulated from each other.

  In the display device according to the first aspect of the present invention, the first touch sensing wiring may be formed on the second surface, and the second touch sensing wiring may be formed on the first surface. Good.

  In the display device according to the first aspect of the present invention, the first touch sensing wiring and the second touch sensing wiring are sequentially formed on the first surface in the observation direction, and the first touch sensing is performed. An insulating layer may be provided between the wiring and the second touch sensing wiring, and the first touch sensing wiring and the second touch sensing wiring may be electrically insulated from each other.

  In the display device according to the first aspect of the present invention, at least the gate wiring among the plurality of wirings electrically linked to the active element is composed of a silver layer, a silver alloy layer, a copper layer, and a copper alloy layer. A layer selected from the group may have a three-layer structure sandwiched by conductive metal oxide layers.

  In the display device according to the first aspect of the present invention, the light emitting layer may include a light emitting diode layer.

  In the display device according to the first aspect of the present invention, the light emitting layer may include an organic electroluminescent layer.

  A display device substrate according to a second aspect of the present invention is a display device substrate used in the display device according to the first aspect of the present invention, wherein the first conductive layer and the second conductive layer are a silver layer, a silver layer, and a silver layer. A layer selected from the group consisting of an alloy layer, a copper layer, and a copper alloy layer has a three-layer structure sandwiched by conductive metal oxide layers.

  In the display device substrate according to the second aspect of the present invention, the conductive metal oxide layer is selected from the group consisting of indium oxide, zinc oxide, antimony oxide, tin oxide, gallium oxide, and bismuth oxide. You may form with the complex oxide containing 2 or more types of metal oxides.

  In the display device substrate according to the second aspect of the present invention, the conductive metal oxide layer is formed of a composite oxide containing indium oxide, zinc oxide, and tin oxide, and indium contained in the composite oxide ( The atomic ratio represented by In / (In + Zn + Sn) of In), zinc (Zn), and tin (Sn) may be greater than 0.8, and the atomic ratio of Zn / Sn may be greater than 1.

  In the display device substrate according to the second aspect of the present invention, the plurality of pixels may include a color filter.

  According to the display device and the display device substrate according to the aspect of the present invention, silver or a silver alloy having high conductivity, or copper or a copper alloy is used as an electrode or wiring constituting a display device using an organic EL or a light emitting diode. This makes it possible to realize a better touch sensing function and higher image quality.

It is a block diagram which shows the control part (a video signal control part, a system control part, and a touch sensing control part) and a display part which comprise the display apparatus which concerns on 1st Embodiment of this invention. FIG. 4 is a view partially showing the display device according to the first embodiment of the present invention, and is a cross-sectional view taken along line A-A ′ of FIG. 3. It is a figure which shows the opposing board | substrate with which the display apparatus which concerns on 1st Embodiment of this invention is provided, Comprising: It is the top view which looked at the display apparatus from the observer side. It is a top view showing the pattern of the 1st conductive layer which constitutes the 1st touch sensing wiring provided in the counter substrate concerning a 1st embodiment of the present invention. It is a top view which shows the pattern of the 2nd conductive layer which comprises the 2nd touch sensing wiring provided in the counter substrate which concerns on 1st Embodiment of this invention. It is a figure which shows the 1st touch sensing wiring, insulating layer, and 2nd touch sensing wiring which were provided in the opposing board | substrate which concerns on 1st Embodiment of this invention, Comprising: The expansion shown which shows the part shown by the code | symbol W1 in FIG. It is sectional drawing. FIG. 4 is an enlarged view partially showing the display device according to the first embodiment of the present invention, and is a cross-sectional view taken along line B-B ′ of FIG. 3. FIG. 8 is a view partially showing a lower electrode (pixel electrode) constituting the display device according to the first embodiment of the present invention, and is an enlarged cross-sectional view showing a portion indicated by reference sign W <b> 2 in FIG. 7. It is an enlarged view which shows partially the gate electrode which comprises the display apparatus which concerns on 1st Embodiment of this invention. It is sectional drawing which shows partially the display apparatus which concerns on 2nd Embodiment of this invention. It is sectional drawing which shows partially the display apparatus which concerns on 3rd Embodiment of this invention. It is a figure which shows the 2nd touch sensing wiring which comprises the display apparatus which concerns on 3rd Embodiment of this invention, Comprising: It is an expanded sectional view which shows the part shown by the code | symbol W3 in FIG. It is sectional drawing which shows partially the display apparatus which concerns on 4th Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the following description, the same or substantially the same functions and components are denoted by the same reference numerals, and the description thereof is omitted or simplified, or only when necessary. In each of the drawings, the dimensions and ratios of the respective components are appropriately changed from the actual ones in order to make the respective components large enough to be recognized on the drawings. In addition, if necessary, illustrations of elements that are difficult to illustrate, for example, a configuration of a plurality of layers that form a semiconductor channel layer, a configuration of a plurality of layers that form a conductive layer, and a part of the configurations are omitted. .

In each of the embodiments described below, characteristic parts will be described. For example, description of parts having no difference between components used in a normal display device and the display device according to the present embodiment will be omitted. .
In the following description, wirings, electrodes, and signals related to touch sensing may be simply referred to as touch drive wirings, touch detection wirings, touch wirings, touch electrodes, and touch signals. In addition, the first touch sensing wiring and the second touch sensing wiring may be simply referred to as touch sensing wiring. A voltage applied to the touch sensing wiring for performing the touch sensing drive is referred to as a touch drive voltage.
The first black layer and the second black layer may be simply referred to as a black layer, and the first conductive layer and the second conductive layer may be simply referred to as a conductive layer.
A voltage applied between the upper electrode and the lower electrode (hereinafter, the lower electrode may be referred to as a pixel electrode or a reflective electrode) in order to drive the light emitting layer (organic EL or LED) is referred to as a pixel driving voltage. The driving of the light emitting layer is sometimes simply referred to as pixel driving.

(First embodiment)
(Functional configuration of display device DSP1)
Hereinafter, a display device DSP1 according to a first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a block diagram showing a control unit and a display unit constituting the display device DSP1 according to the first embodiment of the present invention.
The control unit 120 has a known configuration, and includes a video signal control unit 121 (first control unit), a touch sensing control unit 122 (second control unit), and a system control unit 123 (third control unit). I have.

  The video signal control unit 121 controls image display on the display unit 110. Specifically, the video signal controller 121 is sandwiched between the upper electrode and the lower electrode by controlling the voltage (pixel driving voltage) supplied between the upper electrode and the lower electrode provided on the array substrate 200. The light emission (pixel drive) of the light emitting layer 92 is controlled. Such pixel driving is performed in each of the plurality of light emitting layers 92 provided in an array on the array substrate 200, and an image is displayed on the display unit 110.

  For example, the touch sensing control unit 122 applies a touch sensing driving voltage to the second touch sensing wiring 2 and changes the capacitance generated between the first touch sensing wiring 1 and the second touch sensing wiring 2 described later. Detect and perform touch sensing.

  The system control unit 123 controls the video signal control unit 121 and the touch sensing control unit 122 to alternately perform pixel driving and detection of a change in capacitance due to touch driving. That is, the system control unit 123 can perform image display (pixel drive) and touch sensing drive on the display unit 110 by time-division drive. The system control unit 123 may have a function of performing the above-described driving by making the frequencies of pixel driving and touch sensing driving different from each other, or by making the driving voltages of the pixel driving and touch sensing driving different from each other. It may have a function to perform. In the system control unit 123 having such a function, for example, a frequency of noise from the external environment picked up by the display device DSP1 is detected, and a touch sensing driving frequency different from the noise frequency is selected. Thereby, the influence of noise can be reduced. Further, in such a system control unit 123, a touch sensing driving frequency can be selected in accordance with the scanning speed of a pointer such as a finger or a pen.

  The display device DSP1 including the control unit 120 is a touch sensing function-integrated display device that has both a touch sensing function and an image display function. The display device DSP1 uses a capacitive touch sensing technology using two wiring groups arranged via an insulating layer, that is, a plurality of first touch sensing wirings 1 and a plurality of second touch sensing wirings 2. We are using. For example, when a pointer such as a finger contacts or approaches a counter substrate (described later), a change in capacitance that occurs at the intersection of the first touch sensing wiring 1 and the second touch sensing wiring 2 is detected. The position of the pointer is detected.

(Structure of display device DSP1)
FIG. 2 is a view partially showing the display device DSP1 according to the first embodiment of the present invention, and is a cross-sectional view taken along the line AA ′ of FIG.
The display device DSP1 according to the present embodiment includes a display device substrate according to an embodiment described later. The “plan view” described below means a plane viewed from the direction in which the observer observes the display surface (the plane of the display device substrate) of the display device DSP1. The shape of the display unit of the display device according to the embodiment of the present invention, the shape of the pixel opening defining the pixel, and the number of pixels constituting the display device are not limited.

In the embodiment described in detail below, the direction along the short side of the display unit is defined as the X direction (first direction), the direction along the long side of the display unit is defined as the Y direction (second direction), and The display device will be described with the thickness direction of the transparent substrate defined as the Z direction.
In the following embodiments, the X direction and the Y direction defined as described above are switched, that is, the X direction is defined as the second direction and the Y direction is defined as the first direction, and the display device is configured. May be.

  As shown in FIG. 2, the display device DSP <b> 1 includes a counter substrate 100 (display device substrate) and an array substrate 200 that is bonded to face the counter substrate 100. In the display device DSP1 shown in FIG. 2, an optical film having various optical functions, a cover glass for protecting the counter substrate 100, and the like are omitted.

(Structure of counter substrate 100)
As shown in FIG. 2, the counter substrate 100 includes a transparent substrate 40 having a first surface F and a second surface S opposite to the first surface F. The first surface F is a surface facing the array substrate 200. The second surface S is a surface facing the observer.
The substrate that can be used as the transparent substrate 40 may be a substrate that is transparent in the visible range, and a glass substrate, a ceramic substrate, a quartz substrate, a sapphire substrate, a plastic substrate, or the like can be used.
A plurality of first touch sensing wires 1 and a plurality of second touch sensing wires 2 are provided above the second surface S of the transparent substrate 40. An insulating layer I (touch wiring insulating layer) is provided between the plurality of first touch sensing wires 1 and the plurality of second touch sensing wires 2, and the first touch sensing wire 1 and the second touch sensing wire are provided. 2 are electrically insulated from each other by an insulating layer I.

FIG. 3 is a diagram showing the counter substrate 100 included in the display device DSP1 according to the first embodiment of the present invention, and is a plan view of the display device DSP1 viewed from the observer side P. FIG.
FIG. 4 is a plan view showing a pattern of the first conductive layer constituting the first touch sensing wiring 1 provided on the counter substrate 100 according to the first embodiment of the present invention.
FIG. 5 is a plan view showing a pattern of the second conductive layer constituting the second touch sensing wiring 2 provided on the counter substrate 100 according to the first embodiment of the present invention.

(Touch sensing wiring)
The plurality of first touch sensing wires 1 are positioned above the second surface S, are arranged in the X direction, and extend in the Y direction in parallel with each other. A first terminal TM1 is provided at an end of the first touch sensing wiring 1 in the Y direction. The plurality of first touch sensing wirings 1 form a first wiring pattern.
The plurality of second touch sensing wirings 2 (second wiring patterns) are located between the plurality of first touch sensing wirings 1 and the array substrate 200, and are located above the second surface S in the present embodiment. ing. The second touch sensing wiring 2 has a sense wiring 2A and a lead wiring 2B. The sense wirings 2A are arranged in the Y direction and extend in the X direction in parallel with each other. The sense wiring 2 </ b> A is connected to the lead-out wiring 2 </ b> B outside the display unit 110. The lead wires 2B are arranged in the X direction and extend in the Y direction in parallel with each other. A second terminal TM2 is provided at the end of the lead-out wiring 2B in the Y direction. The plurality of second touch sensing wirings 2 form a second wiring pattern.
Each of the plurality of first touch sensing wires 1 and each of the plurality of second touch sensing wires 2 are electrically independent. The first touch sensing wiring 1 and the sense wiring 2A are orthogonal to each other when viewed from the observer side P. A region defined by the plurality of first touch sensing wires 1 and the plurality of sense wires 2A is a pixel PX. The plurality of pixels PX are arranged in a matrix in the display unit 110. The shape of the opening in the pixel PX may be a square pattern, a rectangular pattern, a parallelogram pattern, or the like. Furthermore, the arrangement of the openings in the pixel PX may be an arrangement with moire countermeasures or a zigzag arrangement.

The plurality of first terminals TM1 and the plurality of second terminals TM2 are connected to the touch sensing control unit 122. Accordingly, the touch sensing control unit 122 is electrically connected to the first touch sensing wiring 1 and the second touch sensing wiring 2 through the first terminal TM1 and the second terminal TM2.
For example, the first touch sensing wiring 1 can be used as a touch detection electrode, and the second touch sensing wiring 2 can be used as a touch drive electrode. The touch sensing control unit 122 detects a change in the capacitance C1 that occurs between the first touch sensing wiring 1 and the second touch sensing wiring 2 as a touch signal.
Further, the role of the first touch sensing wiring 1 and the role of the second touch sensing wiring 2 may be interchanged. Specifically, the first touch sensing wiring 1 may be used as a touch drive electrode, and the second touch sensing wiring 2 may be used as a touch detection electrode.

  Note that all of the first touch sensing wiring 1 and the second touch sensing wiring 2 may not be used for touch sensing. Of the plurality of first touch sensing wires 1 and the plurality of second touch sensing wires 2, wires that are not used for touch sensing may be thinned out except for wires used for touch sensing. That is, thinning driving may be performed.

  Next, a case where the first touch sensing wiring 1 is thinned out will be described. First, all the first touch sensing wires 1 are divided into a plurality of groups. The number of groups is less than the number of all first touch sensing wires 1. Assume that the number of wires constituting one group is, for example, six. Here, out of all the wirings (the number of wirings is six), for example, two wirings are selected (the number smaller than the number of all the wirings, two <6). In one group, touch sensing is performed using two selected wirings, and the potentials of the remaining four wirings are set to floating potentials. Since the display device DSP1 has a plurality of groups, touch sensing can be performed for each group in which the wiring function is defined as described above. Similarly, thinning driving may be performed also in the second touch sensing wiring 2.

  A pointer used for touching is a finger and a pen is different in the area and capacity of a pointer that is in contact with or close to the pointer. The number of wires to be thinned out can be adjusted by such a large pointer. A pointer with a thin tip such as a pen or a needle tip can reduce the number of thinned wires and use a high-density touch sensing wiring matrix. Even during fingerprint authentication, a high-density touch sensing wiring matrix can be used.

  By performing touch sensing drive for each group in this way, the number of wires used for scanning or detection is reduced, so that the touch sensing speed can be increased. Further, in the above example, the number of wirings constituting one group is six. However, for example, one group is formed by the number of wirings of 10 or more, and two wirings selected in one group are connected. It may be used for touch sensing. That is, the number of thinned-out wirings (the number of wirings having a floating potential) is increased, thereby reducing the density of selected wirings used for touch sensing (the density of selected wirings with respect to the total number of wirings). By performing detection, it contributes to reduction of power consumption and improvement of touch detection accuracy. Conversely, by reducing the number of thinned lines, increasing the density of selected lines used for touch sensing, and performing scanning or detection using the selected lines, it can be used for, for example, fingerprint authentication or touch pen input.

  For example, the thinned wiring (wiring not used for touch sensing) is in an electrically floating state, that is, the potential is in a floating state. In order to obtain the proximity distance between the surface of the display device DSP1 (the surface facing the observer) and a pointer such as a finger, the potential of the first touch sensing wiring 1 or the second touch sensing wiring 2 can be set in a floating state. . After detecting the position of a pointer such as a finger, either the first touch sensing wiring 1 or the second touch sensing wiring 2 may be grounded and reset in order to improve the accuracy of the next detection signal (potential) To 0V). Further, in order to improve the accuracy of the detection signal, a voltage that alternately inverts the phase of the touch drive voltage may be employed. Such means for improving the accuracy of the touch detection signal is also effective when the pointer is an active pointer (for example, a pointer that generates a detection instruction signal from a pen-shaped pointer).

Regarding the floating pattern in the thinning driving described above, the first touch sensing wiring 1 and the second touch sensing wiring 2 may perform high-definition touch sensing by switching the detection electrode and the driving electrode by driving the switching element. .
Further, the above-described floating pattern in the thinning drive can be switched so as to be electrically connected to the ground (grounded to the housing). In order to improve the S / N ratio of touch sensing, when a touch sensing signal is detected, a signal wiring of an active element such as a TFT (thin film transistor) may be temporarily grounded to a ground (a housing or the like).

  Also, touch wiring that requires a relatively long time to reset the capacitance detected by touch sensing control, that is, touch wiring with a large time constant (product of capacitance and resistance) in touch sensing may be used. is there. In this case, for example, in the arrangement of touch wirings, odd-numbered wirings and even-numbered wirings may be alternately used for touch sensing to perform driving with the time constant adjusted.

  Further, driving and detection may be performed by grouping a plurality of touch wires. In the drive of grouping a plurality of touch wirings, the line sequential drive may not be adopted, and a collective detection drive method called a self-detection method may be adopted for each group. Moreover, you may perform a parallel drive per group. Further, in order to cancel noise such as parasitic capacitance, a difference detection method that takes a difference between detection signals of adjacent or adjacent touch wirings may be employed. Touch sensing wiring located in a region close to the frame portion (a region outside the display unit 110 and a region where image display is not performed) tends to be less sensitive to touch sensing than a touch sensing wiring located in the center of the display unit 110. There is. For this reason, the sensitivity difference may be reduced by adjusting the width and shape of the touch sensing wiring.

  In the touch sensing control unit 122 and the video signal control unit 121, touch driving and pixel driving can be controlled by time-division driving. The frequency of touch driving may be adjusted according to the required speed of touch input. The touch drive frequency can be higher than the pixel drive frequency. Since the touch timing with a pointer such as a finger is irregular and short, it is desirable that the touch drive frequency be high.

  Several means are known for making the frequency of each of the touch drive and the pixel drive different. For example, on the display screen, a black display is inserted between a plurality of continuous white displays (when a video signal is output) for displaying the video, and touch sensing is performed during this black display period, thereby displaying the video. Touch sensing that is not affected by the noise involved is possible. In the black display period, various touch driving frequencies can be selected arbitrarily.

(Laminated structure of touch sensing wiring)
FIG. 6 is a diagram illustrating the first touch sensing wiring 1, the insulating layer I, and the second touch sensing wiring 2 provided on the counter substrate 100 according to the first embodiment of the present invention. It is an expanded sectional view which shows the part shown by.
In the present embodiment, the direction in which the observer P observes the display device DSP1, that is, the direction from the second surface S to the first surface F of the transparent substrate 40 is the observation direction OB (the Z direction shown in FIG. 2 is (Opposite direction).
The plurality of first touch sensing wires 1 have a configuration in which the first black layer 16 and the first conductive layer 15 are sequentially stacked in the observation direction OB. The plurality of second touch sensing wires 2 have a configuration in which the second black layer 26 and the second conductive layer 25 are sequentially stacked in the observation direction OB. The second black layer 26 has the same configuration as the first black layer 16. The second conductive layer 25 has the same configuration as the first conductive layer 15. That is, the first touch sensing wiring 1 and the second touch sensing wiring 2 have the same layer structure.
The insulating layer I is provided above the second surface S and is disposed between the first touch sensing wiring 1 and the second touch sensing wiring 2.

Since each of the first touch sensing wiring 1 and the second touch sensing wiring 2 includes a black layer, the first touch sensing wiring 1 and the second touch sensing wiring 2 orthogonal to the lattice function function as a black matrix, Improve display contrast.
In FIG. 6, each of the first touch sensing wiring 1 and the second touch sensing wiring 2 has a two-layer laminated structure composed of a black layer and a conductive layer, but the present invention limits this structure. do not do. Each of the first touch sensing wiring 1 and the second touch sensing wiring 2 may be formed in a stacked structure having more layers than two layers. Further, a three-layer laminated structure in which a conductive layer is sandwiched between two black layers may be employed.

The first conductive layer 15 may have, for example, a three-layer structure in which a copper alloy layer that is the metal layer 20 is sandwiched between a first conductive metal oxide layer 21 and a second conductive metal oxide layer 22.
In a cross-sectional view, the line widths of the black layer and the conductive layer constituting each of the first touch sensing wiring 1 and the second touch sensing wiring 2 can be made substantially the same. Specifically, after forming a conductive layer using a known photolithography technique, the dry etching using the patterned conductive layer as a mask is performed, so that the line width in a cross-sectional view of the black layer and the conductive layer is obtained. Can be formed so that they are substantially the same. For example, the technique described in JP-A-2015-004710 can be applied.

(Conductive metal oxide layer)
The metal layer 20 constituting at least part of the first conductive layer 15 and the second conductive layer 25 can be sandwiched between the conductive metal oxide layers 21 and 22. In other words, as a structure of the first conductive layer 15 and the second conductive layer 25, a three-layer structure including the first conductive metal oxide layer 21, the metal layer 20, and the second conductive metal oxide layer 22 is used. Can be adopted. At the interface between the first conductive metal oxide layer 21 and the metal layer 20 or the interface between the second conductive metal oxide layer 22 and the metal layer 20, nickel, zinc, indium, titanium, molybdenum, tungsten, etc. A metal different from copper or an alloy layer of these metals may be further inserted.
Specifically, the first conductive metal oxide layer 21 and the second conductive metal oxide layer 22 are made of, for example, indium oxide, zinc oxide, antimony oxide, tin oxide, gallium oxide, and bismuth oxide. A composite oxide containing two or more metal oxides selected from the group described above can be employed. By adjusting the composition of these metal oxides, the value of the work function can be adjusted, and the carrier emission property when an organic EL is employed as the light emitting layer can be adjusted.

The amount of indium (In) contained in the first conductive metal oxide layer 21 and the second conductive metal oxide layer 22 needs to be greater than 80 at%.
That is, the conductive metal oxide layer is formed of a composite oxide containing indium oxide, zinc oxide, and tin oxide, and indium (In), zinc (Zn), and tin (Sn) contained in the composite oxide. The atomic ratio represented by / (In + Zn + Sn) is larger than 0.8, and the atomic ratio of Zn / Sn is larger than 1.
The amount of indium (In) is preferably greater than 80 at%. More preferably, the amount of indium (In) is greater than 90 at%. When the amount of indium (In) is less than 80 at%, the specific resistance of the conductive metal oxide layer to be formed increases, which is not preferable. If the amount of zinc (Zn) exceeds 20 at%, the alkali resistance of the conductive metal oxide (mixed oxide) decreases, which is not preferable. In the first conductive metal oxide layer 21 and the second conductive metal oxide layer 22 described above, both atomic percentages of metal elements in the mixed oxide (counting only metal elements not counting oxygen elements) It is. Antimony oxide and bismuth oxide can be added to the conductive metal oxide layer because metal antimony and metal bismuth hardly form a solid solution region with copper and suppress diffusion of copper in the laminated structure.

  When the first conductive metal oxide layer 21 and the second conductive metal oxide layer 22 contain tin oxide and zinc oxide, the amount of zinc (Zn) needs to be larger than the amount of tin (Sn). . If the tin content exceeds the zinc content, there will be problems with wet etching in the subsequent process. In other words, the metal layer made of copper or copper alloy is more easily etched than the conductive metal oxide layer, and the first conductive metal oxide layer 21, the metal layer 20, the second conductive metal oxide layer 22, A difference in width with the metal layer 20 is likely to occur.

When the first conductive metal oxide layer 21 and the second conductive metal oxide layer 22 contain tin oxide and zinc oxide, the first conductive metal oxide layer 21 and the second conductive metal oxide layer 22 The amount of tin (Sn) contained is preferably in the range of 0.5 at% to 6 at%. In comparison with indium element, by adding tin of 0.5 at% or more and 6 at% or less to the conductive metal oxide layer, a ternary mixed oxide film of indium, zinc, and tin (conductive composite) The specific resistance of the oxide layer can be reduced. If the amount of tin exceeds 6 at%, zinc is also added to the conductive metal oxide layer, so that the specific resistance of the ternary mixed oxide film (conductive composite oxide layer) becomes too large. By adjusting the amount of zinc and tin within the above range (0.5 at% or more and 6 at% or less), the specific resistance is approximately 3 × 10 ⁻⁴ Ωcm or more as the specific resistance of the single layer film of the mixed oxide film. It can be contained within a small range of 5 × 10 ⁻⁴ Ωcm or less. A small amount of other elements such as titanium, zirconium, magnesium, aluminum, and germanium can be added to the mixed oxide. However, in this embodiment, the specific resistance of the mixed oxide is not limited to the above range.

(Conductive layer)
The first conductive layer 15 and the second conductive layer 25 can be formed of a conductive material such as the metal layer 20. Examples of the metal layer 20 include a copper layer, a copper alloy layer, a silver layer, a silver alloy layer, an aluminum alloy layer containing aluminum (aluminum-containing layer), gold, titanium, molybdenum, or an alloy thereof. Can be adopted. Since nickel is a ferromagnetic material, it can be formed by vacuum film formation such as sputtering although the film formation rate is lowered. Chromium has the disadvantage of environmental pollution and a large resistance value, but can be used as a material for the metal layer according to the present embodiment. In order to obtain adhesion of the conductive layer to the transparent substrate 40 and the transparent resin layer, it is composed of copper, silver, or aluminum, magnesium, calcium, titanium, molybdenum, indium, tin, zinc, neodymium, nickel, aluminum, antimony. It is preferable to employ an alloy to which one or more metal elements selected from the group are added.

  As a metal layer used for the first conductive layer 15 and the second conductive layer 25 constituting each of the first touch sensing wiring 1 and the second touch sensing wiring 2, 1.5 at% calcium is added to silver. A silver alloy can be used. In each of the first conductive layer 15 and the second conductive layer 25, a three-layer structure in which the silver alloy layer is sandwiched by a composite oxide layer containing indium oxide, zinc oxide, and tin oxide can be used.

  In a three-layer structure sandwiched between conductive metal oxide layers, for example, magnesium or calcium added to copper or silver is selectively oxidized during heat treatment, and is formed at the interface between the conductive metal oxide and the metal layer. Easy to precipitate. Alternatively, magnesium oxide or calcium oxide tends to precipitate on the surface or cross section of a copper alloy or silver alloy by oxidation. Such selective oxidation or precipitation suppresses migration of copper and silver, and as a result, the reliability of the three-layer laminated structure can be improved. The amount of the metal element added to the metal layer 20 is preferably 4 at% or less because the resistance value of the copper alloy or the silver alloy is not increased greatly. As a film formation method for the copper alloy or silver alloy, for example, a vacuum film formation method such as sputtering can be used.

  When a copper alloy thin film, a silver alloy thin film, or an aluminum alloy thin film is employed as the metal layer 20, when the film thickness is 100 nm or more or 150 nm or more, visible light is hardly transmitted. Therefore, if the metal layer 20 which concerns on this embodiment has a film thickness of 100 nm-300 nm, for example, sufficient light-shielding property can be obtained. The film thickness of the metal layer 20 may exceed 300 nm. As will be described later, the material of the conductive layer can also be applied to wirings and electrodes provided on an array substrate described later. In the present embodiment, as a wiring structure that is electrically linked to the active element, for example, a stacked structure in which a metal layer is sandwiched between conductive metal oxide layers is employed as a structure of a gate electrode or a gate wiring. be able to.

  When the metal layer 20 is a copper layer, a copper alloy layer, or a silver layer or a silver alloy, the conductive metal oxide layer described above is selected from indium oxide, zinc oxide, antimony oxide, gallium oxide, bismuth oxide, and tin oxide. It is desirable that the composite oxide contains two or more metal oxides. A copper layer, a copper alloy layer, or a silver layer or a silver alloy has low adhesion to a transparent resin layer or a glass substrate (transparent substrate) constituting the color filter. For this reason, when a copper layer, a copper alloy layer, or a silver layer or a silver alloy copper layer is applied to a display device substrate as it is, it is difficult to realize a practical display device substrate. However, the composite oxide described above has sufficient adhesion to a color filter (colored patterns of a plurality of colors), a black matrix BM (black layer), a glass substrate (transparent substrate), and the like, and a copper layer. Adhesiveness to the copper alloy layer is also sufficient. For this reason, when a copper alloy layer or a silver alloy layer is applied to a display device substrate using a composite oxide, a practical display device substrate can be realized.

  In addition, as the metal layer 20 used for the gate electrode and the gate wiring constituting the thin film transistor, a silver alloy in which 1.5 at% calcium is added to silver can be used. A three-layer structure in which the silver alloy layer is sandwiched between composite oxide layers containing indium oxide, zinc oxide, and tin oxide can be used.

  Copper, copper alloys, silver, silver alloys, or oxides and nitrides thereof generally do not have sufficient adhesion to a transparent substrate such as glass, a black matrix, or the like. Therefore, when the conductive metal oxide layer is not provided, peeling may occur at the interface between the touch sensing wiring and a transparent substrate such as glass, or at the interface between the touch sensing wiring and the black layer. When copper or copper alloy is used as the first touch sensing wiring 1 and the second touch sensing wiring 2 having a thin wiring pattern, a conductive metal oxide layer is not formed as a base layer of a metal layer (copper or copper alloy). In the display device substrate (counter substrate), in addition to defects due to peeling, defects due to electrostatic breakdown may occur in the touch sensing wiring during the manufacturing process of the display device substrate, which is not practical. Such electrostatic breakdown in the first touch sensing wiring 1 and the second touch sensing wiring 2 is a post process in which a color filter, a black matrix or the like is laminated on a transparent substrate, and a process in which the display device substrate and the array substrate are bonded together. Alternatively, static electricity is accumulated in the wiring pattern by a cleaning process or the like, and the pattern is broken or disconnected due to electrostatic breakdown.

  Copper, copper alloy, silver or silver alloy has high electrical conductivity and is preferable as a wiring material. However, non-conductive copper oxide is formed over time on the surface of the copper alloy, and electrical contact may be difficult. Silver and silver alloys easily form sulfides and oxides. On the other hand, a stable ohmic contact can be realized by covering a copper alloy layer or a silver alloy layer with a composite oxide layer such as indium oxide, zinc oxide, antimony oxide, and tin oxide. In the case of using layers, electrical mounting such as transfer can be easily performed in a third embodiment described later.

  Examples of the layer structure composed of the first conductive metal oxide layer 21, the metal layer 20, and the second conductive metal oxide layer 22 applicable to the embodiment of the present invention include the following modifications. It is done. For example, ITO (Indium Tin Oxide) or IZTO (Indium Zinc Tin Oxide, where Z is zinc oxide) containing indium oxide as a central base material is electrically conductive on a metal layer such as a copper alloy layer. Layer structure obtained by forming a conductive metal oxide layer, or molybdenum oxide, tungsten oxide, mixed oxide of nickel oxide and copper oxide, titanium oxide, etc. on a metal layer such as aluminum alloy or copper alloy Examples thereof include a layer structure obtained by laminating these metal oxides. The three-layer structure in which the metal layer is sandwiched between the conductive metal oxide layers has an advantage that the film can be continuously formed by a vacuum film forming apparatus such as a sputtering apparatus.

  For example, from the viewpoint of collectively etching the silver alloy layer and the conductive metal oxide layer, a composite oxide containing zinc oxide or gallium oxide can be used for the conductive metal oxide layer sandwiching the silver alloy. Such a laminated structure of the silver alloy layer and the conductive metal oxide layer can be patterned by a single etching with one etchant by a known photolithography technique. For example, a composite oxide of indium oxide, gallium oxide, and antimony oxide can be used as a conductive metal oxide layer as a later-described organic EL light-reflective pixel electrode. A composite oxide of indium oxide, gallium oxide, and antimony oxide has a high work function. As an anode of an organic EL display device, a stacked structure of a composite oxide of indium oxide, gallium oxide, and antimony oxide and a silver alloy layer is suitable for a pixel electrode.

  The first conductive metal oxide layer 21 and the second conductive metal oxide layer 22 have a barrier property against copper and silver. In a structure in which a copper wiring or silver wiring is sandwiched between conductive metal oxides, deterioration of the active element due to migration of copper or silver can be suppressed, which is preferable as a highly conductive wiring for the active element.

(Black layer)
The first black layer 16 and the second black layer 26 function as a black matrix of the display device DSP1. The black layer is made of, for example, a colored resin in which a black color material is dispersed. Copper oxides and copper alloy oxides are difficult to obtain sufficient black color and low reflectance. For example, when the black layer is formed of a metal oxide, it has a light reflectance in the visible range of approximately 10% to 30%, and it appears to be colored with difficulty in obtaining a flat reflectance in the visible range. The visible light reflectance at the interface between the black layer and the substrate such as glass or the transparent resin layer according to the present embodiment is suppressed to about 3% or less, and high visibility is obtained. The transparent resin includes an adhesive layer for attaching a protective glass to the display device.

  As the black color material, carbon, carbon nanotube, carbon nanohorn, carbon nanobrush, or a mixture of a plurality of organic pigments can be applied. For example, carbon is used as a main color material at a ratio of 51% by mass or more with respect to the total amount of the black color material. In order to adjust the reflection color, an organic pigment such as blue or red can be added to the black color material. For example, the reproducibility of the black layer in the photolithography process can be improved by adjusting the concentration of carbon contained in the photosensitive black coating liquid that is the starting material (lowering the carbon concentration).

  Even when a large exposure apparatus which is a manufacturing apparatus of the display apparatus DSP1 is used, for example, a black layer having a pattern having a width (thin line) of 1 to 9 μm can be formed (patterning). In addition, the range of the carbon concentration in this embodiment is set in the range of 4 to 50% by mass with respect to the total solid content including the resin, the curing agent, and the pigment. Here, as the amount of carbon, the carbon concentration may exceed 50% by mass. However, when the carbon concentration exceeds 50% by mass with respect to the entire solid content, the suitability of the coating film tends to decrease. In addition, when the carbon concentration is set to less than 4% by mass, sufficient black color cannot be obtained, and reflected light generated in the underlying metal layer located under the black layer is greatly recognized, thereby reducing visibility. is there.

When exposure processing is performed in photolithography, which is a subsequent process, alignment between the substrate to be exposed and the mask is performed. At this time, priority is given to alignment, and for example, the optical density of the black layer by transmission measurement can be made 2 or less. In addition to carbon, a black layer may be formed using a mixture of a plurality of organic pigments as a black color adjustment. Considering the refractive index (about 1.5) of the base material such as glass or transparent resin, the reflectance of the black layer is such that the reflectance at the interface between the black layer and the base material is 3% or less. Is set. In this case, it is desirable to adjust the content and type of the black color material, the resin used for the color material, and the film thickness. By optimizing these conditions, the reflectance at the interface between the black layer having a refractive index of approximately 1.5 and the black layer is set to 3% or less in the visible wavelength range. And low reflectivity can be realized. For example, it is possible to prevent the reflected light caused by the light emitted from the light emitting layer from entering the active element and malfunctioning. When the active element included in the array substrate has sensitivity in the visible light region, reflected light from the back surface of the conductive layer may enter the active element and cause the active element to malfunction. By disposing the black layer together with the opposite side (back surface of the conductive layer) close to the display function layer, it is possible to prevent malfunction of the active element due to incidence of reflected light.
In consideration of improving the visibility of the observer, the reflectance of the black layer is desirably 3% or less. In general, the refractive index of the acrylic resin used for the color filter and the liquid crystal material is approximately in the range of 1.5 to 1.7. Note that a color filter including a plurality of colored pixels of red, green, and blue may be provided on the counter substrate.

(Structure of array substrate 200)
Next, the structure of the array substrate 200 constituting the display device DSP1 will be described.
The substrate 45 of the array substrate 200 need not be a transparent substrate. For example, as a substrate applicable to the array substrate 200, a glass substrate, a ceramic substrate, a quartz substrate, a sapphire substrate, silicon, silicon carbide, silicon germanium, or the like can be used. A semiconductor substrate, a plastic substrate, etc. are mentioned.
In the array substrate 200, the fourth insulating layer 14, the active element 68 formed on the fourth insulating layer 14, the third insulating layer 13 formed so as to cover the fourth insulating layer 14 and the active element 68, the active element 68, the gate electrode 95 formed on the third insulating layer 13 so as to face the channel layer 58, the second insulating layer 12 formed so as to cover the third insulating layer 13 and the gate electrode 95, and the second insulating layer. A planarizing layer 96 formed on the layer 12 is sequentially stacked on the substrate 45.

A contact hole 93 is formed in the planarizing layer 96 at a position corresponding to the drain electrode 56 of the active element 68. A bank 94 is formed on the planarization layer 96 at a position corresponding to the channel layer 58. In a region between the banks 94 adjacent to each other in a cross-sectional view, that is, in a region surrounded by the banks 94 in a plan view, the upper surface of the planarization layer 96, the inside of the contact hole 93, and the drain electrode 56 are covered. A lower electrode 88 (pixel electrode) is formed on the substrate. Note that the lower electrode 88 may not be formed on the upper surface of the bank 94.
Further, a hole injection layer 91 is formed so as to cover the lower electrode 88, the bank 94, and the planarization layer 96. On the hole injection layer 91, a light emitting layer 92, an upper electrode 87, and a sealing layer 109 are sequentially stacked.
As will be described later, the lower electrode 88 has a configuration in which a silver or silver alloy layer is sandwiched between conductive metal oxide layers.
In FIG. 2, reference numeral 29 indicates a light emitting region constituted by the lower electrode 88, the hole injection layer 91, the light emitting layer 92, and the upper electrode 87.

The upper electrode 87 is, for example, a transparent conductive film in which a silver alloy layer having a thickness of 11 nm is sandwiched between complex oxides having a thickness of 40 nm. The lower electrode 88 has a structure in which a silver alloy layer having a thickness of 250 nm is sandwiched between complex oxides having a thickness of 30 nm. The composite oxide layer is applied to the conductive metal oxide layer, and the film thickness of the silver alloy layer is set, for example, in the range of 9 nm to 15 nm, and the silver alloy layer is sandwiched between the conductive metal oxide layers. It is preferable to use a three-layer structure. In this case, a transparent conductive film having a high transmittance can be realized.
In addition, the composite oxide layer is applied to the conductive metal oxide layer, and the film thickness of the silver alloy layer is set within a range of, for example, 100 nm to 250 nm, or 300 nm or more. A three-layer structure in which a silver alloy layer is sandwiched between physical layers may be adopted. In this case, a reflective electrode having a high reflectance with respect to visible light can be realized.

As a material of the bank 94, an organic resin such as an acrylic resin, a polyimide resin, or a novolac phenol resin can be used. The bank 94 may be further laminated with an inorganic material such as silicon oxide or silicon oxynitride.
As a material for the planarization layer 96, an acrylic resin, a polyimide resin, a benzocyclobutene resin, a polyamide resin, or the like may be used. A low dielectric constant material (low-k material) can also be used.
In order to improve visibility, any of the planarization layer 96, the sealing layer 109, or the substrate 45 may have a light scattering function. Alternatively, a light scattering layer may be formed above the substrate 45.

(Active element 68)
FIG. 7 is an enlarged view partially showing the display device DSP1 according to the first embodiment of the present invention, and is a cross-sectional view taken along the line BB ′ of FIG. FIG. 7 shows an example of a structure of a thin film transistor (TFT) having a top gate structure used as the active element 68 connected to the pixel electrode. In FIG. 7, the counter substrate 100 and the sealing layer 109 are omitted.

  The active element 68 includes a channel layer 58, a drain electrode 56 connected to one end of the channel layer 58 (first end, the left end of the channel layer 58 in FIG. 7), and the other end (second end, FIG. 7 on the right end of the channel layer 58 in FIG. 7 and a gate electrode 95 disposed opposite to the channel layer 58 with the third insulating layer 13 interposed therebetween. As will be described later, the channel layer 58 is in contact with the gate insulating layer and is made of an oxide semiconductor. The active element 68 drives the light emitting layer.

  FIG. 7 shows a structure in which the channel layer 58, the drain electrode 56, and the source electrode 54 constituting the active element 68 are formed on the fourth insulating layer 14, but the present invention limits such a structure. do not do. The active element 68 may be formed directly on the substrate 45 without providing the fourth insulating layer 14. A bottom-gate thin film transistor may be used.

  The source electrode 54 and the drain electrode 56 shown in FIG. 7 are formed simultaneously in the same process. The source electrode 54 and the drain electrode 56 include conductive layers having the same configuration. In the first embodiment, a three-layer structure such as titanium / aluminum alloy / titanium and molybdenum / aluminum alloy / molybdenum can be adopted as the structure of the source electrode 54 and the drain electrode 56. Here, the aluminum alloy is an aluminum-neodymium alloy.

  The third insulating layer 13 located below the gate electrode 95 may be an insulating layer having the same width as the gate electrode 95. In this case, for example, dry etching using the gate electrode 95 as a mask is performed, and the third insulating layer 13 around the gate electrode 95 is removed. Thus, an insulating layer having the same width as the gate electrode 95 can be formed. A technique for processing an insulating layer by dry etching using the gate electrode 95 as a mask is generally called self-alignment.

Driving an organic EL or LED using a thin film transistor including a channel layer formed of an oxide semiconductor is preferable to driving using a thin film transistor including a channel layer formed of a polysilicon semiconductor.
For example, oxide semiconductors called IGZO are collectively formed by vacuum film formation such as sputtering. After the oxide semiconductor is formed, heat treatment after forming a pattern such as a TFT is also performed in a lump. For this reason, variation in electrical characteristics (for example, Vth) related to the channel layer is extremely small. In order to suppress variations in luminance when driving an organic EL or LED, it is necessary to suppress variations in Vth of the thin film transistor within a small range.

  On the other hand, in a thin film transistor having a channel layer formed of a polysilicon semiconductor, it is necessary to perform laser annealing of amorphous silicon, which is a precursor of the thin film transistor, to each of the transistors. Will be invited. From this viewpoint, the thin film transistor used in the display device including the organic EL or LED is preferably a thin film transistor including a channel layer formed of an oxide semiconductor.

  In addition, a thin film transistor including a channel layer formed using an oxide semiconductor has extremely low leakage current, and thus has high stability after a scan signal or a video signal is input. A thin film transistor including a channel layer formed of a polysilicon semiconductor has a leakage current larger by two digits or more than an oxide semiconductor transistor. It is preferable that this leakage current is small because it leads to highly accurate touch sensing.

  As a material of the channel layer 58, for example, an oxide semiconductor called IGZO can be used. The oxide semiconductor material constituting the channel layer 58 includes a metal oxide containing at least one selected from the group consisting of gallium, indium, zinc, tin, aluminum, germanium, and cerium, and at least antimony and A material containing any one of bismuth and a metal oxide can be used.

  In this embodiment, an oxide semiconductor containing indium oxide, gallium oxide, and zinc oxide is used. The material of the channel layer 58 formed using an oxide semiconductor may be any of single crystal, polycrystal, microcrystal, a mixture of microcrystal and amorphous, or amorphous. The film thickness of the oxide semiconductor can be a film thickness in the range of 2 nm to 50 nm. The channel layer 58 may be formed of a polysilicon semiconductor.

  Furthermore, a structure in which two thin film transistors are stacked may be employed. In this case, a thin film transistor including a channel layer formed of a polysilicon semiconductor is used as a thin film transistor located in a lower layer. A thin film transistor including a channel layer formed using an oxide semiconductor is used as a thin film transistor positioned in an upper layer. In such a structure in which two thin film transistors are stacked, the thin film transistors are arranged in a matrix in a plan view. In this structure, high mobility is obtained by the polysilicon semiconductor, and low leakage current can be realized by the oxide semiconductor. That is, both the merit of the polysilicon semiconductor and the merit of the oxide semiconductor can be utilized together.

An oxide semiconductor or a polysilicon semiconductor can be used, for example, in the configuration of a complementary transistor having a p / n junction, or can be used in the configuration of a single channel transistor having only an n-type junction. As the stacked structure of oxide semiconductors, for example, a stacked structure in which an n-type oxide semiconductor and an n-type oxide semiconductor having different electrical characteristics from the n-type oxide semiconductor may be used. The n-type oxide semiconductor to be stacked may include a plurality of layers. In the stacked n-type oxide semiconductor, the band gap of the underlying n-type semiconductor can be different from the band gap of the n-type semiconductor located in the upper layer.
For example, a configuration in which the upper surface of the channel layer is covered with a different oxide semiconductor may be employed.
Alternatively, for example, a stacked structure in which a microcrystalline (close to amorphous) oxide semiconductor is stacked over a crystalline n-type oxide semiconductor may be employed. Here, the microcrystal refers to a microcrystalline oxide semiconductor film obtained by heat-treating an amorphous oxide semiconductor formed with a sputtering apparatus in a range of 180 ° C. to 450 ° C., for example. Alternatively, it refers to a microcrystalline oxide semiconductor film formed with the substrate temperature at the time of film formation set to around 200 ° C. The microcrystalline oxide semiconductor film is an oxide semiconductor film in which crystal grains of at least about 1 nm to about 3 nm or larger than 3 nm can be observed by an observation method such as TEM.
An oxide semiconductor can be improved in carrier mobility and reliability by being changed from amorphous to crystalline. The melting point as an oxide of indium oxide or gallium oxide is high. Antimony oxide and bismuth oxide have melting points of 1000 ° C. or lower, and oxides have low melting points. For example, when a ternary composite oxide of indium oxide, gallium oxide, and antimony oxide is employed, the crystallization temperature of the composite oxide can be lowered due to the effect of antimony oxide having a low melting point. In other words, an oxide semiconductor that can be easily crystallized from an amorphous state to a microcrystalline state can be provided. An oxide semiconductor can improve carrier mobility and reliability by increasing crystallinity thereof.

As an oxide semiconductor, zinc oxide, gallium oxide, or antimony oxide-rich composite oxide can be used because it is required to be easily soluble in wet etching in a later step. For example, the atomic ratio of the metal element of the target used for sputtering is In: Ga: Zn = 1: 2: 2, In: Ga: Zn = 1: 3: 3, In: Ga: Zn = 2: 1: 1. Or, In: Ga: Zn = 1: 1: 1 can be exemplified. Here, Zn can be replaced with, for example, Sb (antimony) or Bi (bismuth).
For example, a binary composite oxide of indium oxide and antimony oxide may be used at an atomic ratio of In: Sb = 1: 1. For example, a binary composite oxide of indium oxide and bismuth oxide may be used at an atomic ratio of In: Bi = 1: 1.
Further, in the atomic ratio, the In content may be further increased.
Note that the composition of the composite oxide is not limited to the above composition.

For example, Sn may be added to the above complex oxide. In this case, a composite oxide including a quaternary composition including In ₂ O ₃ , Ga ₂ O ₃ , Sb ₂ O ₃ , and SnO ₂ is obtained, or In ₂ O ₃ , Sb ₂ O ₃ , and A composite oxide containing a ternary composition containing SnO ₂ is obtained, and the carrier concentration can be adjusted. SnO ₂ having a different valence from In ₂ O ₃ , Ga ₂ O ₃ , Sb ₂ O ₃ , and Bi ₂ O ₃ serves as a carrier dopant.
For example, sputtering film formation is performed using a target obtained by adding tin oxide to a ternary metal oxide containing indium oxide, gallium oxide, and antimony oxide. Thereby, a composite oxide with an improved carrier concentration can be formed. Similarly, for example, by performing sputtering film formation using a target obtained by adding tin oxide to a ternary metal oxide of indium oxide, gallium oxide, and bismuth oxide, a composite oxide with improved carrier concentration is obtained. A film can be formed.

However, if the carrier concentration becomes too high, the threshold value Vth of a transistor having a channel layer formed of a complex oxide tends to be negative (it is likely to be normally on). For this reason, it is desirable to adjust the amount of tin oxide added so that the carrier concentration is less than 1 × 10 ¹⁸ cm ⁻³ . Regarding the carrier concentration and carrier mobility, the film formation conditions of the composite oxide (oxygen gas used for the introduced gas, substrate temperature, film formation rate, etc.), the annealing conditions after film formation, and the composition of the composite oxide By adjusting the above, a desired carrier concentration and carrier mobility can be obtained. For example, increasing the composition ratio of indium oxide tends to improve carrier mobility. For example, crystallization of the composite oxide can be promoted by an annealing process in which heat treatment is performed at a temperature of 250 ° C. to 700 ° C., and carrier mobility of the composite oxide can be improved.

  Furthermore, a thin film transistor (active element) having a channel layer formed of an n-type oxide semiconductor and a thin film transistor (active element) having a channel layer formed of an n-type silicon semiconductor are disposed one by one in the same pixel, A light emitting layer such as an LED or an organic EL (OLED) can be driven so as to make use of the characteristics of each channel layer of the thin film transistor. When an LED or an organic EL (OLED) is used as the light emitting layer, an n-type polysilicon thin film transistor is adopted as a driving transistor for applying a voltage (current) to the light emitting layer, and an n type is used as a switching transistor for sending a signal to the polysilin thin film transistor. An oxide semiconductor thin film transistor can be employed.

  The drain electrode 56 and the source electrode 54 can adopt the same structure. For example, multiple conductive layers can be used for the drain electrode 56 and the source electrode 54. For example, an electrode structure in which aluminum, copper, or an alloy layer thereof is sandwiched between molybdenum, titanium, tantalum, tungsten, a conductive metal oxide layer, or the like can be employed. On the fourth insulating layer 14, the drain electrode 56 and the source electrode 54 may be formed first, and the channel layer 58 may be formed so as to be stacked on these two electrodes. The structure of the transistor may be a multi-gate structure such as a double gate structure.

  The semiconductor layer or the channel layer may be adjusted in mobility and electron concentration in the thickness direction. The semiconductor layer or the channel layer may have a stacked structure in which different oxide semiconductors are stacked. The channel length of the transistor determined by the minimum distance between the source electrode and the drain electrode can be 10 nm to 10 μm, for example, 20 nm to 0.5 μm.

  The third insulating layer 13 functions as a gate insulating layer. Such insulating layer materials include hafnium silicate (HfSiOx), silicon oxide, aluminum oxide, silicon nitride, silicon oxynitride, aluminum oxynitride, zirconium oxide, gallium oxide, zinc oxide, hafnium oxide, cerium oxide, lanthanum oxide, Or the insulating layer etc. which were obtained by mixing these materials are employ | adopted. Cerium oxide has a high dielectric constant and a strong bond between cerium and oxygen atoms. For this reason, it is preferable that the gate insulating layer be a composite oxide containing cerium oxide. Even when cerium oxide is employed as one of the oxides constituting the composite oxide, it is easy to maintain a high dielectric constant even in an amorphous state. Cerium oxide has an oxidizing power. Cerium oxide is capable of storing and releasing oxygen. Therefore, a structure in which an oxide semiconductor and cerium oxide are in contact with each other can supply oxygen from the cerium oxide to the oxide semiconductor, avoid oxygen vacancies in the oxide semiconductor, and provide a stable oxide semiconductor (channel layer). Can be realized. The structure using nitride for the gate insulating layer does not exhibit the above-described action. The material of the gate insulating layer may include a lanthanoid metal silicate represented by cerium silicate (CeSiOx). Alternatively, lanthanum cerium composite oxide, and further lanthanum cerium silicate may be included.

  The structure of the third insulating layer 13 may be a single layer film, a mixed film, or a multilayer film. In the case of a mixed film or multilayer film, the mixed film or multilayer film can be formed of a material selected from the above insulating layer materials. The film thickness of the third insulating layer 13 is a film thickness that can be selected from a range of 2 nm to 300 nm, for example. In the case where the channel layer 58 is formed using an oxide semiconductor, the interface of the third insulating layer 13 in contact with the channel layer 58 can be formed in a state containing a large amount of oxygen (film formation atmosphere).

  In a thin film transistor manufacturing process, in a thin film transistor having a top gate structure, a gate insulating layer containing cerium oxide can be formed in an introduced gas containing oxygen after an oxide semiconductor is formed. At this time, the surface of the oxide semiconductor located under the gate insulating layer can be oxidized, and the degree of oxidation of the surface can be adjusted. In a thin film transistor having a bottom gate structure, it is difficult to adjust the degree of oxidation of the surface of the oxide semiconductor because the formation process of the gate insulating layer is performed before the oxide semiconductor process. In a thin film transistor having a top gate structure, oxidation of the surface of the oxide semiconductor can be promoted more than in the bottom gate structure, and oxygen vacancies in the oxide semiconductor are less likely to occur.

  The plurality of insulating layers including the planarization layer 96, the second insulating layer 12, the third insulating layer 13, and the insulating layer (fourth insulating layer 14) underlying the oxide semiconductor are formed using an inorganic insulating material or an organic insulating material. Can be formed. As a material of the insulating layer, silicon oxide, silicon oxynitride, and aluminum oxide can be used. As a structure of the insulating layer, a single layer or a plurality of layers including the above materials can be used. A configuration in which a plurality of layers formed of different insulating materials are stacked may be employed. In order to obtain the effect of planarizing the upper surface of the insulating layer, an acrylic resin, a polyimide resin, a benzocyclobutene resin, a polyamide resin, or the like may be used for some of the insulating layers. A low dielectric constant material (low-k material) can also be used.

  A gate electrode 95 is disposed on the channel layer 58 via the third insulating layer 13. Further, the gate electrode 95 may be formed using the same material as the drain electrode 56 and the source electrode 54 described above so as to have the same layer structure. As the structure of the gate electrode 95, a structure in which a copper layer or a copper alloy layer is sandwiched between conductive metal oxides, or a structure in which silver or a silver alloy is sandwiched between conductive metal oxides can be employed.

FIG. 9 is an enlarged view partially showing an example of the gate electrode 95 constituting the display device DSP1 according to the first embodiment of the present invention.
In the structure shown in FIG. 9, the metal layer 20 constituting the gate electrode 95 is formed of a copper layer or a copper alloy layer, or silver or a silver alloy. In the gate electrode 95, the metal layer 20 is sandwiched between conductive metal oxide layers 97 and 98. As a material of the conductive metal oxide layers 97 and 98, the conductive metal oxide constituting the conductive metal oxide layers 21 and 22 described in the first embodiment can be used.

  The surface of the metal layer 20 exposed at the end of the gate electrode 95 can be covered with a complex oxide containing indium. Alternatively, the entire gate electrode 95 may be covered with a nitride such as silicon nitride or molybdenum nitride so as to include the end portion (cross section) of the gate electrode 95. Alternatively, an insulating film having the same composition as the gate insulating layer described above may be stacked with a thickness greater than 50 nm.

As a method for forming the gate electrode 95, prior to the formation of the gate electrode 95, only the third insulating layer 13 positioned immediately above the channel layer 58 of the active element 68 is subjected to dry etching or the like, so that the thickness of the third insulating layer 13 is increased. Can also be made thinner.
Oxide semiconductors having different electrical properties may be further inserted at the interface of the gate electrode 95 that is in contact with the third insulating layer 13. Alternatively, the third insulating layer 13 may be formed of an insulating metal oxide layer containing cerium oxide or gallium oxide.

In the case where a copper alloy is used for part of the structure of the gate electrode 95, a metal element or a metalloid element in a range of 0.1 at% or more and 4 at% or less can be added to copper. Thus, the effect that copper migration can be suppressed is obtained by adding an element to copper. In particular, elements that can be placed at the lattice position of copper by substituting a part of copper atoms in the crystal of the copper layer (grains), and the movement of copper atoms in the vicinity of the copper grains precipitated at the grain boundaries of the copper layer It is preferable to add to the copper together with an element that suppresses the above. Alternatively, in order to suppress the movement of the copper atom, it is preferable to add an element heavier than the copper atom (having a larger atomic weight) to the copper. In addition, it is preferable to select an additive element in which the conductivity of copper is less likely to decrease with an addition amount within a range of 0.1 at% to 4 at% with respect to copper. Furthermore, in consideration of vacuum film formation such as sputtering, an element having a film formation rate such as sputtering close to copper is preferable. As described above, the technique of adding an element to copper can also be applied when copper is replaced with silver or aluminum. In other words, a silver alloy or an aluminum alloy may be used instead of the copper alloy.
Adding an element that can be placed in the copper lattice position to replace a part of the copper atoms in the crystal (grain) of the copper layer means that, in other words, a metal or metalloid that forms a solid solution with copper near room temperature. It is to be added to copper. Examples of the metal that easily forms a solid solution with copper include manganese, nickel, zinc, palladium, gallium, and gold (Au). Adding an element to copper that precipitates at the grain boundary of the copper layer and suppresses the movement of copper atoms in the vicinity of the copper grain is, in other words, adding a metal or metalloid that does not form a solid solution with copper near room temperature. That is. There are various materials for metals and metalloids that do not form a solid solution with copper or that do not easily form a solid solution with copper. For example, refractory metals such as titanium, zirconium, molybdenum, and tungsten, and elements called semimetals such as silicon, germanium, antimony, and bismuth can be used. The alloy element can be used as an additive element added to the silver alloy.

  Copper and silver have a problem in reliability from the viewpoint of migration. Reliability can be supplemented by adding the above metals and metalloids to copper. The effect of suppressing migration can be obtained by adding 0.1 at% or more of the above metal or metalloid to copper or silver. However, when the above metal or metalloid is added at a content exceeding 4 at% with respect to copper or silver, the conductivity of copper or silver is significantly deteriorated, and the merit of selecting a copper alloy or silver alloy is obtained. Absent.

(Light emitting layer 92)
As shown in FIG. 7, the array substrate 200 includes a light emitting layer 92 (organic EL layer) that is a display function layer. In the light emitting layer 92, when an electric field is applied between a pair of electrodes, holes injected from an anode (for example, an upper electrode) and electrons injected from a cathode (for example, a lower electrode, a pixel electrode) are recombined. It is a display functional layer that is excited and emits light.
The light emitting layer 92 contains at least a material having a light emitting property (light emitting material), and preferably contains a material having an electron transporting property. The light emitting layer 92 is a layer formed between the anode and the cathode. When the hole injection layer 91 is formed on the lower electrode 88 (anode), the hole injection layer 91 and the upper electrode 87 (cathode) are formed. The light emitting layer 92 is formed between the two. When a hole transport layer is formed on the anode, the light emitting layer 92 is formed between the hole transport layer and the cathode. The roles of the upper electrode 87 and the lower electrode 88 can be interchanged.

  The film thickness of the light emitting layer 92 is arbitrary as long as the effects of the present invention are not significantly impaired. However, it is preferable that the film thickness is large from the viewpoint that defects are unlikely to occur in the film. On the other hand, when the film thickness is small, the drive voltage is low, which is preferable. For this reason, the film thickness of the light emitting layer 92 is preferably 3 nm or more, more preferably 5 nm or more, and on the other hand, it is usually preferably 200 nm or less, and more preferably 100 nm or less.

The material of the light emitting layer 92 is not particularly limited as long as it emits light at a desired light emission wavelength and does not impair the effects of the present invention, and a known light emitting material can be applied. The light emitting material may be a fluorescent light emitting material or a phosphorescent light emitting material, but a material having good light emission efficiency is preferred, and a phosphorescent light emitting material is preferred from the viewpoint of internal quantum efficiency.
Examples of the light emitting material that gives blue light emission include naphthalene, perylene, pyrene, anthracene, coumarin, chrysene, p-bis (2-phenylethenyl) benzene, and derivatives thereof. Examples of the light emitting material that gives green light emission include quinacridone derivatives, coumarin derivatives, aluminum complexes such as Al (C ₉ H ₆ NO) _{3, and the} like.
Examples of the light-emitting material that gives red light emission include DCM (4- (dicyanomethylene) -2-methyl-6- (p-dimethylaminostyryl) -4H-pyran) compounds, benzopyran derivatives, rhodamine derivatives, benzothioxanthene derivatives, aza Examples include benzothioxanthene.
The configuration of the organic EL layer constituting the light emitting layer 92 and the light emitting material are not limited to the above materials.

As shown in FIG. 7, the light emitting layer 92 is formed on the hole injection layer 91 and is driven by a driving voltage applied between the upper electrode 87 and the lower electrode 88.
The lower electrode 88 has a structure in which a reflective layer 89 and conductive metal oxide layers 97 and 98 are laminated. In addition to the light emitting layer 92, an electron injection layer, an electron transport layer, a hole transport layer, or the like may be inserted between the upper electrode 87 and the lower electrode 88.
For the hole injection layer 91, a refractory metal oxide such as tungsten oxide or molybdenum oxide can be used. For the reflective layer 89, a silver alloy, an aluminum alloy, or the like having a high light reflectance can be used. Note that conductive metal oxides such as ITO do not have good adhesion to aluminum. For example, when the interface such as the electrode or the contact hole is made of ITO and an aluminum alloy, poor electrical connection is likely to occur. Silver or a silver alloy has good adhesion to a conductive metal oxide such as ITO, and a conductive metal oxide such as ITO easily obtains an ohmic contact.

FIG. 8 is a view partially showing a lower electrode 88 (pixel electrode) constituting the display device DSP1 according to the first embodiment of the present invention, and is an enlarged cross section showing a portion indicated by reference numeral W2 in FIG. FIG.
As shown in FIG. 8, in this embodiment, in order to suppress silver migration, the lower electrode 88 has a silver or silver alloy layer (reflective layer 89) sandwiched between conductive metal oxide layers 97 and 98 3. It has a layer structure. As a material of the conductive metal oxide layers 97 and 98, the conductive metal oxide constituting the conductive metal oxide layers 21 and 22 described in the first embodiment can be used.

When applying a silver alloy layer to a light-reflective pixel electrode (lower electrode), the film thickness of a silver alloy layer can be selected from the range of 100 nm to 500 nm, for example. If necessary, the film thickness may be greater than 500 nm. Further, when the film thickness of the silver alloy layer is, for example, 9 nm to 15 nm, the silver alloy layer can be used for the light transmissive upper electrode or the counter electrode.
Further, regarding the display function layer, when a liquid crystal layer is used instead of the light emitting layer 92 (organic EL layer), the silver alloy layer is changed to a pixel electrode (lower electrode) by changing the film thickness of the silver alloy layer from 100 nm to 500 nm. And a reflective liquid crystal display device can be realized.

In this embodiment, a composite oxide of indium oxide, gallium oxide, and antimony oxide is used as the conductive metal oxide. As a material of the silver alloy layer, a silver alloy that functions as a conductive layer can be applied. As the additive element added to silver, one or more metal elements selected from the group consisting of magnesium, calcium, titanium, molybdenum, indium, tin, zinc , neodymium, nickel, antimony, bismuth, copper, and the like are used. be able to. The silver alloy layer of this embodiment was a silver alloy in which 1.5 at% calcium was added to silver. Calcium is selectively oxidized by heat treatment or the like in a subsequent process in a configuration in which a silver alloy is sandwiched between the conductive metal oxides. By forming such an oxide, the reliability of the structure in which the silver alloy layer is sandwiched between the conductive metal oxide layers can be improved. Furthermore, the reliability can be further improved by covering the structure in which the silver alloy layer is sandwiched by the conductive metal oxide layer with a nitride such as silicon nitride or molybdenum nitride.

The counter substrate 100 and the array substrate 200 described above are bonded together via the first transparent resin layer 108 as shown in FIG.
It should be noted that in a seal portion (not shown) where the counter substrate 100 and the array substrate 200 are bonded together, it is also possible to perform conduction transfer (transfer) from the counter substrate 100 to the array substrate 200 in the thickness direction of the seal portion. is there. By disposing a conductor selected from an anisotropic conductive film, a minute metal sphere, or a resin sphere covered with a metal film in the seal portion, the counter substrate 100 and the array substrate 200 can be electrically connected.

(Modification of the first embodiment)
In the above embodiment, the structure in which the organic electroluminescence layer (organic EL) is employed as the light emitting layer 92 has been described. The light emitting layer 92 may be an inorganic light emitting diode layer. The light emitting layer 92 may have a structure in which inorganic LED chips are arranged in a matrix. In this case, a small LED chip for each of red light emission, green light emission, and blue light emission may be mounted on the array substrate 200. As a method of mounting the LED chip on the array substrate 200, mounting by face-down may be performed.

  When the light emitting layer 92 is composed of an inorganic LED, a blue light emitting diode or a blue-violet light emitting diode is disposed on the array substrate 200 (substrate 45) as the light emitting layer 92. After forming the nitride semiconductor layer and the upper electrode, a green phosphor is laminated on the green pixel, and a red phosphor is laminated on the red light emitting pixel. Thereby, inorganic LED can be simply formed in the array board | substrate 200. FIG. When such a phosphor is used, green light emission and red light emission can be obtained from each of the green phosphor and the red phosphor by excitation with blue light generated from the blue-violet light emitting diode.

  Alternatively, an ultraviolet light emitting diode may be disposed on the array substrate 200 (substrate 45) as the light emitting layer 92. In this case, after forming the nitride semiconductor layer and the upper electrode, a blue phosphor is laminated on the blue pixel, a green phosphor is laminated on the green pixel, and a red phosphor is laminated on the red pixel. Thereby, inorganic LED can be simply formed in the array board | substrate 200. FIG. When such a phosphor is used, for example, a green pixel, a red pixel, or a blue pixel can be formed by a simple method such as a printing method. For these pixels, it is desirable to adjust the size of the pixels from the viewpoint of the light emission efficiency and color balance of each color.

  In the embodiment described above, the first touch sensing wiring 1 and the second touch sensing wiring 2 are disposed above the second surface S. The present invention does not limit this structure. For example, one of the first touch sensing wiring 1 and the second touch sensing wiring 2 may be disposed on the second surface S, and the other wiring may be disposed on the first surface F. Further, the first touch sensing wiring 1 and the second touch sensing wiring 2 may be disposed on the first surface F. Such a structure will be described below.

(Second Embodiment)
The second embodiment of the present invention will be described below with reference to the drawings.
In the second embodiment, the same members as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted or simplified.
FIG. 10 is a sectional view partially showing a display device DSP2 according to the second embodiment of the present invention. In the display device DSP2, an organic EL is used as a display function layer (light emitting layer).

  The counter substrate 300 constituting the display device DSP2 of the second embodiment includes a transparent substrate 42 having a first surface F and a second surface S opposite to the first surface F. A plurality of first touch sensing wires 1 are provided on the second surface S. A plurality of second touch sensing wires 2 are provided on the first surface F. That is, the second touch sensing wiring 2 is located between the first touch sensing wiring 1 and the array substrate 400. The plurality of second touch sensing wires 2 and the first surface F are covered with a second transparent resin layer 105. In the structure shown in FIG. 10, the first transparent resin layer 108 and the second transparent resin layer 105 are bonded together.

In the touch sensing drive, a change in the capacitance C2 is detected at the intersection where the first touch sensing wiring 1 and the second touch sensing wiring 2 are orthogonal. Each of the plurality of first touch sensing wires 1 and the plurality of second touch sensing wires 2 is electrically independent. The first touch sensing wiring 1 and the second touch sensing wiring 2 are orthogonal to each other in plan view. For example, the first touch sensing wiring 1 can be used as a touch detection electrode, and the second touch sensing wiring 2 can be used as a touch drive electrode. The touch sensing control unit 122 detects a change in the capacitance C2 that occurs between the first touch sensing wiring 1 and the second touch sensing wiring 2 as a touch signal.
Further, the role of the first touch sensing wiring 1 and the role of the second touch sensing wiring 2 may be interchanged. Specifically, the first touch sensing wiring 1 may be used as a touch drive electrode, and the second touch sensing wiring 2 may be used as a touch detection electrode.

  As each structure of the 1st touch sensing wiring 1 and the 2nd touch sensing wiring 2, the same structure as the cross-sectional structure shown in FIG. 6 demonstrated in 1st Embodiment is employable. The first touch sensing wiring 1 has a configuration in which a first black layer 16 and a first conductive layer 15 are sequentially stacked. As the structure of the first conductive layer 15, for example, three layers in which a copper alloy layer or a silver alloy layer that is the metal layer 20 is sandwiched between the first conductive metal oxide layer 21 and the second conductive metal oxide layer 22. It can be a structure. The first touch sensing wiring 1 and the second touch sensing wiring 2 orthogonal to the grid also serve as a black matrix for improving display contrast.

  In the second embodiment, the active element 68 has the same top gate structure as that of the first embodiment. The channel layer of the second embodiment is also formed of an oxide semiconductor, as in the first embodiment. Furthermore, from the viewpoint of electron mobility of the transistor, the first layer is formed of an active matrix including a channel layer formed of a polysilicon semiconductor, and the active matrix is provided of a channel layer formed of an oxide semiconductor. It is preferable to adopt a structure in which the second layer is laminated. In the structure in which the first layer and the second layer are stacked in this way, for example, an active element (first layer) including a channel layer formed of a polysilicon semiconductor has a carrier ( It is used as a driving element for injecting electrons or holes. An active element (second layer) including a channel layer formed of an oxide semiconductor is used as a switching element that selects an active element including a channel layer formed of a polysilicon semiconductor. A silver alloy layer or a copper alloy layer sandwiched between conductive metal oxide layers can be used as a power line for emitting light from the organic EL layer that is electrically linked to the drive element. As such a structure, for example, a wiring structure shown in FIG. 9 is used. It is preferable to apply a silver alloy or a copper alloy having good conductivity to the wiring linked to the active element such as a power supply line.

  In the second embodiment, the metal layer 20 made of a copper alloy is used for the gate electrode 95. As shown in FIG. 9, the metal layer 20 constituting the gate electrode 95 is sandwiched between a first conductive metal oxide layer 97 and a second conductive metal oxide layer 98. The material used for the gate insulating layer, which is the third insulating layer 13, is the same as in the first embodiment.

(Third embodiment)
Hereinafter, a third embodiment of the present invention will be described with reference to the drawings.
In 3rd Embodiment, the same code | symbol is attached | subjected to the same member as 1st Embodiment and 2nd Embodiment, and the description is abbreviate | omitted or simplified.
FIG. 11 is a sectional view partially showing a display device DSP3 according to the third embodiment of the present invention.

The counter substrate 500 constituting the display device DSP3 of the third embodiment includes a transparent substrate 44 having a first surface F and a second surface S opposite to the first surface F. On the second surface S, no touch sensing wiring is provided. In the first surface F, a plurality of first touch sensing wires 1 and a plurality of second touch sensing wires 2 are formed in this order in the observation direction OB (see FIG. 6, the direction opposite to the Z direction). . That is, the second touch sensing wiring 2 is located between the first touch sensing wiring 1 and the array substrate 600. The plurality of second touch sensing wires 2 and the first surface F are covered with a second transparent resin layer 105.
An insulating layer I (touch wiring insulating layer) is provided between the plurality of first touch sensing wires 1 and the plurality of second touch sensing wires 2, and the first touch sensing wire 1 and the second touch sensing wire are provided. 2 are electrically insulated from each other by an insulating layer I.
In the structure shown in FIG. 11, the first transparent resin layer 108 and the second transparent resin layer 105 are bonded together.

FIG. 12 is a diagram showing the second touch sensing wiring 2 constituting the display device DSP3 according to the third embodiment of the present invention, and is an enlarged cross-sectional view showing a portion indicated by a symbol W3 in FIG.
As shown in FIG. 12, the second touch sensing wiring 2 has a configuration in which a second black layer 76 and a second conductive layer 75 are sequentially stacked in the observation direction OB. The second black layer 76 has the same configuration as the second black layer 26 of the first embodiment. The second conductive layer 75 has the same configuration as the second conductive layer 25 of the first embodiment.

In the touch sensing drive, a change in the capacitance C3 is detected at an intersection where the first touch sensing wiring 1 and the second touch sensing wiring 2 are orthogonal to each other. Each of the plurality of first touch sensing wires 1 and the plurality of second touch sensing wires 2 is electrically independent. The first touch sensing wiring 1 and the second touch sensing wiring 2 are orthogonal to each other in plan view. For example, the first touch sensing wiring 1 can be used as a touch detection electrode, and the second touch sensing wiring 2 can be used as a touch drive electrode. The touch sensing control unit 122 detects a change in the capacitance C3 that occurs between the first touch sensing wiring 1 and the second touch sensing wiring 2 as a touch signal.
Further, the role of the first touch sensing wiring 1 and the role of the second touch sensing wiring 2 may be interchanged. Specifically, the first touch sensing wiring 1 may be used as a touch drive electrode, and the second touch sensing wiring 2 may be used as a touch detection electrode.

  As in the first and second embodiments, the active element 68 of the third embodiment includes an oxide semiconductor channel layer, and the gate insulating layer of the active element 68 is formed of a complex oxide containing cerium oxide. Has been.

(Fourth embodiment)
Hereinafter, a fourth embodiment of the present invention will be described with reference to the drawings.
In the fourth embodiment, the same members as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted or simplified.
FIG. 13 is a sectional view partially showing a display device DSP4 according to the fourth embodiment of the present invention.

  As shown in FIG. 13, a color filter CF is provided on the first surface F of the transparent substrate 40. The red colored layer R, the green colored layer G, and the blue colored layer B constituting the color filter CF are opposed to the light emitting layer 92. For this reason, each of the plurality of pixels PX includes a color filter. The boundary between the red colored layer R and the green colored layer G, the boundary between the green colored layer G and the blue colored layer B, and the boundary between the blue colored layer B and the red colored layer R are the first touch in plan view. It overlaps with the sensing wiring 1 and the second touch sensing wiring 2. Since the first black layer 16 and the second black layer 26 constituting the first touch sensing wiring 1 and the second touch sensing wiring 2 function as a black matrix, the boundary portion overlaps with the black matrix. For this reason, generation of color mixing of the red colored layer R, the green colored layer G, and the blue colored layer B is prevented from the viewpoint of the observer.

The first transparent resin layer 108 is disposed so as to cover the color filter CF. The counter substrate 700 and the array substrate 200 are bonded together via the first transparent resin layer 108.
According to the fourth embodiment, full color display can be realized as the light emitting layer 92 emits light.

  For example, the display device according to the above-described embodiment can be variously applied. Electronic devices to which the display device according to the above-described embodiments can be applied include mobile phones, portable game devices, portable information terminals, personal computers, electronic books, video cameras, digital still cameras, head mounted displays, navigation systems, sound Examples include playback devices (car audio, digital audio player, etc.), copiers, facsimiles, printers, printer multifunction devices, vending machines, automatic teller machines (ATMs), personal authentication devices, optical communication devices, and the like. Each of the above embodiments can be used in any combination.

  While preferred embodiments of the present invention have been described and described above, it should be understood that these are exemplary of the invention and are not to be considered as limiting. Additions, omissions, substitutions, and other changes can be made without departing from the scope of the invention. Accordingly, the invention is not to be seen as limited by the foregoing description, but is limited by the scope of the claims.

DESCRIPTION OF SYMBOLS 1 ... 1st touch sensing wiring 2 ... 2nd touch sensing wiring 2A ... sense wiring (2nd touch sensing wiring 2)
2B: Lead-out wiring (second touch sensing wiring 2)
15 ... 1st conductive layer 16 ... 1st black layer 12 ... 2nd insulating layer 13 ... 3rd insulating layer 14 ... 4th insulating layer 20 ... Metal layers 21, 97 .... First conductive metal oxide layers 22, 98 ... second conductive metal oxide layers 25, 75 ... second conductive layers 26, 76 ... second black layer 40 ... transparent substrate 42 ... Transparent substrate 44 ... Transparent substrate 45 ... Substrate 54 ... Source electrode 56 ... Drain electrode 58 ... Channel layer 68 ... Active element 87 ... Upper electrode 88 ...・ Lower electrode (pixel electrode)
89 ... reflective layer 91 ... hole injection layer 92 ... light emitting layer 93 ... contact hole 94 ... bank 95 ... gate electrode 96 ... flattening layer 100, 300, 500, 700 ... Counter substrate (display device substrate)
105 ... 2nd transparent resin layer 108 ... 1st transparent resin layer 109 ... Sealing layer 110 ... Display part 120 ... Control part 121 ... Video signal control part 122 ... Touch Sensing control unit 123 ... system control unit 200, 400, 600 ... array substrate F ... first surface S ... second surface I ... insulating layer P ... observer R ... Red colored layer (color filter)
G ... Green colored layer (color filter)
B ... Blue colored layer (color filter)
OB ... Observation direction BM ... Black matrix PX ... Pixel TFT ... Thin film transistor TM1 ... First terminal TM2 ... Second terminals C1, C2, C3 ... Capacitance CF ... -Color filters DSP1, DSP2, DSP3, DSP4 ... display devices

Claims (11)

A display device,
A light-reflective pixel electrode having a structure in which a silver alloy layer in which calcium is added to silver is sandwiched between conductive metal oxide layers, a light- emitting layer that emits light at a driving voltage applied from the pixel electrode, and gate insulation An array substrate comprising: an active element in contact with the layer and having a channel layer made of an oxide semiconductor and driving the light emitting layer;
A transparent substrate having a first surface facing the array substrate and a second surface opposite to the first surface; and a first black layer and a first layer in an observation direction from the second surface toward the first surface A plurality of first touch sensing wires extending in parallel with each other so as to be arranged in the first direction on the second surface, and a second black color in the observation direction. A second direction having a configuration in which a layer and a second conductive layer are sequentially stacked and positioned between the plurality of first touch sensing wires and the array substrate and orthogonal to the first direction in plan view A plurality of second touch sensing wires extending in parallel with each other so as to be lined with each other, and a plurality of pixels partitioned by the plurality of first touch sensing wires and the plurality of second touch sensing wires in a plan view. Display device substrate provided ,
A control unit that performs touch sensing by detecting a change in capacitance between the first touch sensing wiring and the second touch sensing wiring;
Only including,
The oxide semiconductor is
Does not contain zinc-containing metal oxides,
A metal oxide containing one or more selected from the group consisting of gallium, indium, tin, aluminum, germanium, and cerium;
A metal oxide containing at least one of antimony and bismuth;
Including
The gate insulating layer is formed of a complex oxide containing cerium oxide,
The active element is a thin film transistor having a top gate structure.
Display device. The first touch sensing wiring and the second touch sensing wiring are formed on the second surface,
An insulating layer is provided between the first touch sensing wiring and the second touch sensing wiring,
The display device according to claim 1, wherein the first touch sensing wiring and the second touch sensing wiring are electrically insulated from each other. The first touch sensing wiring is formed on the second surface,
The display device according to claim 1, wherein the second touch sensing wiring is formed on the first surface. On the first surface, the first touch sensing wiring and the second touch sensing wiring are sequentially formed in the observation direction,
An insulating layer is provided between the first touch sensing wiring and the second touch sensing wiring,
The display device according to claim 1, wherein the first touch sensing wiring and the second touch sensing wiring are electrically insulated from each other.   Among the plurality of wirings electrically linked to the active element, at least the gate wiring is a conductive metal oxide layer selected from the group consisting of a silver layer, a silver alloy layer, a copper layer, and a copper alloy layer. The display device according to claim 1, wherein the display device has a three-layer structure sandwiched between physical layers.   The display device according to claim 1, wherein the light emitting layer includes a light emitting diode layer.   The display device according to claim 1, wherein the light emitting layer includes an organic electroluminescent layer. A display device substrate used in the display device according to claim 1,
The first conductive layer and the second conductive layer are three layers in which a layer selected from the group consisting of a silver layer, a silver alloy layer, a copper layer, and a copper alloy layer is sandwiched between conductive metal oxide layers A display device substrate having a structure. The conductive metal oxide layer is
9. The composite oxide according to claim 8 , wherein the composite oxide comprises two or more metal oxides selected from the group consisting of indium oxide, zinc oxide, antimony oxide, tin oxide, gallium oxide, and bismuth oxide. Display device substrate. The conductive metal oxide layer is formed of a composite oxide containing indium oxide, zinc oxide, and tin oxide,
The atomic ratio of In / (In + Zn + Sn) of indium (In), zinc (Zn), and tin (Sn) contained in the composite oxide is greater than 0.8, and the atomic ratio of Zn / Sn is 1. 9. The display device substrate of claim 8, which is larger. The display device substrate according to claim 8 , wherein each of the plurality of pixels includes a color filter.

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