KR20110020049A - Touch sensor in-cell type organic electroluminescent device and methode of fabricating the same - Google Patents

Abstract

PURPOSE: A touch sensor in-cell type organic electroluminescent device and a method for manufacturing the same are provided to use the second electrode of an organic electroluminescent diode as the first electrode of a touch sensor, thereby reducing manufacturing costs by minimizing the number of components for the touch sensor. CONSTITUTION: The first electrode(147) contacts a drain electrode of a driving thin film transistor(DTr). A buzzer pattern(150) covers the frame of the first electrode. An organic electroluminescent layer(155) is formed on the first electrode. The second electrode(158) is formed on a display area of the organic electroluminescent layer. The first material layer is formed on a display area of the second electrode. A touch electrode corresponds to a specific pixel area.

Description

Touch sensor in-cell type organic electroluminescent device and manufacturing method thereof {Touch sensor in-cell type organic electroluminescent device and methode of fabricating the same}

The present invention relates to an organic electroluminescent device, and more particularly, to an organic electroluminescent device having a touch sensor built in an in-cell type and a method of manufacturing the same.

The organic light emitting diode, which is one of the flat panel displays (FPDs), has high luminance and low operating voltage characteristics. In addition, the self-luminous self-illuminating type provides high contrast ratio, enables ultra-thin display, easy response time with several microsecond response time, no restriction on viewing angle, and stable at low temperatures. Since it is driven at a low voltage of 5V to 15V of DC, it is easy to manufacture and design a driving circuit.

The organic light emitting device having such characteristics is largely divided into a passive matrix type and an active matrix type. In the passive matrix method, since the scan line and the signal line cross each other and constitute the device in a matrix form, Since the scanning lines are sequentially driven in time to drive the pixels, in order to represent the required average luminance, the instantaneous luminance must be equal to the average luminance multiplied by the number of lines.

However, in the active matrix method, a thin film transistor, which is a switching element for turning on / off a pixel, is positioned for each pixel, and the first electrode connected to the thin film transistor is turned on per pixel. The second electrode which is turned on / off and opposes the first electrode is formed on the entire surface to become a common electrode.

In the active matrix method, a voltage applied to a pixel is charged in a storage capacitor (C _ST ), and the power is applied until the next frame signal is applied, thereby relating to the number of scan lines. Run continuously for one screen without Therefore, since low luminance, high definition, and large size can be obtained even when a low current is applied, an active matrix type organic light emitting diode is mainly used in recent years.

Hereinafter, the basic structure and operation characteristics of the active matrix organic light emitting diode will be described in detail with reference to the accompanying drawings.

1 is a circuit diagram of one pixel of a typical active matrix organic electroluminescent device.

As illustrated, one pixel of the active matrix organic light emitting diode is a switching thin film transistor STr, a driving thin film transistor DTr, a storage capacitor StgC, and an organic light emitting diode E. Is made of.

That is, the gate line GL is formed in the first direction, is formed in the second direction crossing the first direction to define the pixel region P, and the data line DL is formed. A power supply line PL is formed to be spaced apart from the DL and to apply a power supply voltage.

In addition, a switching thin film transistor STr is formed at a portion where the data line DL and the gate wiring GL cross, and a driving thin film transistor DTr electrically connected to the switching thin film transistor STr is formed. have.

In this case, the driving thin film transistor DTr is electrically connected to the organic light emitting diode E. That is, the first electrode, which is one terminal of the organic light emitting diode E, is connected to the drain electrode of the driving thin film transistor DTr, and the second electrode, which is the other terminal, is connected to the power line PL. In this case, the power line PL transfers a power supply voltage to the organic light emitting diode E. In addition, a storage capacitor StgC is formed between the gate electrode and the source electrode of the driving thin film transistor DTr.

Therefore, when a signal is applied through the gate line GL, the switching thin film transistor STr is turned on, and the signal of the data line DL is transferred to the gate electrode of the driving thin film transistor DTr to drive the driving signal. Since the thin film transistor DTr is turned on, light is output through the organic electroluminescent diode E. At this time, when the driving thin film transistor DTr is in an on state, the level of the current flowing from the power supply line PL to the organic light emitting diode E is determined, and thus the organic light emitting diode E is The gray scale may be implemented, and the storage capacitor StgC maintains the gate voltage of the driving thin film transistor DTr constant when the switching thin film transistor STr is turned off. As a result, even when the switching thin film transistor STr is turned off, the level of the current flowing through the organic light emitting diode E may be maintained until the next frame.

2 is a schematic cross-sectional view of a conventional organic EL device.

As illustrated, the first and second substrates 10 and 70 are disposed to face each other, and the edge portions of the first and second substrates 10 and 70 are sealed by a seal pattern 80. In addition, a driving thin film transistor DTr is formed in each pixel region P on the first substrate 10, and a first electrode 47 is formed by being connected to each of the driving thin film transistors DTr. In addition, an organic light emitting layer 55 including a light emitting material corresponding to red, green, and blue colors is formed on the first electrode 47, and on the organic light emitting layer 55. The second electrode 58 is formed on the front surface. In this case, the first and second electrodes 47 and 58 serve to apply an electric field to the organic light emitting layer 55.

The second electrode 47 and the second substrate 58 formed on the first substrate 10 are spaced apart by a predetermined interval by the seal pattern 80 described above.

3 is a cross-sectional view of one pixel area including a driving thin film transistor of a conventional organic EL device.

As shown, on the first substrate 10, the semiconductor layer 13, the gate insulating film 16, and the gate electrode composed of the first region 13a of pure polysilicon and the second region 13b doped with impurities 20), an interlayer insulating film 23 having a semiconductor layer contact hole 25 exposing the second region 13b, and source and drain electrodes 33 and 36 are sequentially stacked to form a driving thin film transistor DTr. The source and drain electrodes 33 and 36 are connected to a power supply wiring (not shown) and an organic light emitting diode E, respectively.

In addition, the organic light emitting diode E includes a first electrode 47 and a second electrode 58 facing each other with the organic light emitting layer 55 interposed therebetween. In this case, the first electrode 47 is formed in contact with one electrode of the driving thin film transistor DTr for each pixel region P, and the second electrode 58 is formed on the entire surface of the organic light emitting layer 55. It is becoming.

In addition, the second substrate 70 is configured to face the first substrate 10 having the above-described structure for encapsulation.

On the other hand, the first electrode 47 is an indium-tin-oxide (ITO) or indium, which is a transparent conductive material having a high work function value to serve as an anode electrode, especially when the driving thin film transistor DTr is p type. It is made of zinc oxide (IZO), and the second electrode 58 is made of a metal material having a low work function value, for example, aluminum (Al) to serve as a cathode electrode.

On the other hand, in recent years, a product with a touch sensor is introduced in mobile phones, PDAs, and laptops that can be personally carried, and attracts a lot of users' attention, and organic light emitting diodes are also used as display devices in these products. In line with this, products with a touch sensor have recently been released.

4 is a schematic cross-sectional view of an organic light emitting diode with a conventional touch sensor.

The organic light emitting device 2 including the conventional touch sensor includes an encapsulation facing the first substrate 10 having a switching and driving thin film transistor (DTr) and an organic light emitting diode (E) formed thereon. The first panel PA1 configured as the second substrate 70 for the touch panel, and the touch first electrode 82 at the bottom and the top thereof, respectively, through the first adhesive layer 72 to the outside of the first panel PA1. Protection formed on the outer surface of the third substrate 80 via the third substrate 80 and the second adhesive layer 92 having the touch second electrode 86 having a plurality of bar shapes spaced apart from the second adhesive layer 92. It consists of 2nd panel PA2 comprised including the sheet | seat 90.

Therefore, it can be seen that the organic light emitting diode 2 including the conventional touch sensor is made of a total of three substrates 10, 70, and 90 even though the protective sheet 90 is excluded.

In this case, the substrates 10, 70, and 90 used in the organic light emitting diode 2 are mainly glass substrates having transparent characteristics, and the organic substrate having a touch sensor TS using three such glass substrates is used. In the case of configuring the EL device 2, the thickness thereof becomes very thick, and the weight thereof becomes relatively heavy, thereby causing a problem of reversing the trend of lighter and thinner display devices.

In addition, since a separate process for forming the touch sensor TS needs to be performed, a problem of complicated process occurs.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an organic light emitting device having a light and thin touch sensor by minimizing the use of a substrate.

In addition, another object is to reduce manufacturing costs by simplifying the manufacturing process by minimizing a device for implementing a touch sensor.

In the touch sensor in-cell type organic light emitting device according to the present invention for achieving the above object, a plurality of pixel regions of a display area are defined, and gate and data lines, power lines, and power lines are connected to each other. A touch sensor in-cell type organic light emitting device comprising a switching thin film transistor, a first substrate including a driving thin film transistor connected to the switching thin film transistor, an organic light emitting diode, and a transparent second substrate facing the pixel; A first electrode formed in contact with the drain electrode of the driving thin film transistor in the region; A buffer pattern formed around the pixel area and covering an edge of the first electrode; An organic emission layer formed on the first electrode in the pixel region; A second electrode formed over the organic light emitting layer on the entire display area; A first material layer formed over the second electrode and over the display area; And a touch electrode formed on the first material layer to correspond to a plurality of specific pixel areas of the plurality of pixel areas, wherein the second electrode, the first layer, and the touch electrode form a touch sensor.

In this case, the organic light emitting layer is formed of red, green, and blue organic light emitting materials, and red, green, and blue organic light emitting layers are sequentially formed in each pixel area to emit red, green, and blue light, respectively. Is a pixel area that emits any one color among the pixel areas emitting red, green, and blue, or a pixel area having a spacing interval of 1 to 10 pixel areas in the display area. .

The specific pixel area may be a pixel area in which a white organic light emitting layer is formed to emit white light when the organic light emitting layer is formed of an organic light emitting material emitting red, green, blue, and white sequentially in each pixel area. It is characteristic.

The polarizing plate may be configured on the outer surface of the second substrate.

In addition, a reflecting plate made of aluminum (Al) or silver (Ag) having excellent reflection efficiency is formed below the first electrode, and the first electrode has a relatively large work function value to serve as an anode electrode. It is made of indium tin oxide (ITO) or indium zinc oxide (IZO), and the second electrode is aluminum (Al), which is a metal material having a relatively low work function value to serve as a cathode electrode, It is made of one of aluminum alloy (AlNd), silver (Ag), magnesium (Mg), gold (Au), aluminum magnesium alloy (AlMg), the touch electrode is a transparent conductive material indium-tin-oxide (ITO) or indium -Zinc-oxide (IZO), wherein a hole injection layer and a hole transporting layer are formed between the first electrode and the organic light emitting layer, and the organic light emitting layer and the second light emitting layer Between the electrodes An electron transporting layer and an electron injection layer may be formed.

A method of manufacturing a touch sensor in-cell type organic light emitting device according to the present invention includes a gate and data wiring, a power wiring, and a gate and data wiring crossing each other on a first substrate having a plurality of pixel regions defined in a display area. Forming a switching thin film transistor connected to the switching thin film transistor and a driving thin film transistor connected to the switching thin film transistor; Forming a first protective layer having a drain contact hole exposing the drain electrode of the driving thin film transistor; Forming a first electrode on the first passivation layer in contact with the drain electrode of the driving thin film transistor through the drain contact hole in each pixel area; Forming a buffer pattern surrounding each pixel area and covering an edge of the first electrode; Forming organic light emitting layers on the first electrodes in the pixel areas, respectively; Forming a second electrode over the display area on the organic light emitting layer; Forming a second passivation layer over the second electrode, over the display area; Forming a touch electrode on the second passivation layer corresponding to a specific pixel area of each pixel area; Bonding the first substrate and the transparent second substrate to face the touch electrode.

In this case, the organic light emitting layer is made of an organic light emitting material that emits red, green, and blue, and the pixel region is sequentially formed red, green, and blue organic light emitting layer to emit red, green, and blue, respectively. The specific pixel region may be a pixel region that emits any one of the red, green, and blue pixel regions, or may be a pixel region arranged to have a spacing interval of 1 to 10 pixel regions. The organic light emitting layer includes an organic light emitting material that emits white in addition to red, green, and blue, and the pixel region sequentially forms red, green, blue, and white organic light emitting layers to emit red, green, blue, and white, respectively. In this case, the specific pixel area is characterized in that the pixel area for emitting the white light.

The method may further include attaching a polarizing plate to an outer surface of the second substrate.

The touch sensor in-cell type organic light emitting device according to the present invention includes a sensor capable of detecting a touch between a first substrate on which an organic light emitting diode is formed and a second substrate for encapsulation. By reducing the use of one substrate compared to the one has the effect of implementing a thin thin.

In addition, by using the second electrode of the organic light emitting diode as the touch first electrode of the touch sensor, it minimizes the components for implementing the touch sensor to simplify the process and further reduce the manufacturing cost.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

5 is a cross-sectional view of a touch sensor in-cell type organic light emitting device according to an exemplary embodiment of the present invention. In this case, for convenience of description, a region in which the switching thin film transistor is to be formed is defined as a switching region and a region in which the driving thin film transistor is to be formed as a driving region.

As illustrated, the touch sensor in-cell type organic light emitting diode 101 according to the present invention includes a driving and switching thin film transistor DTr (not shown), an organic light emitting diode E, and a first substrate 110 on which a touch sensor is formed. ) And a second substrate 170 for encapsulation.

First, the configuration of the first substrate 110 will be described.

The upper portion of the first substrate 110 is made of pure polysilicon in each pixel region P, and a central portion of the first substrate 110 is doped with a high concentration of impurities on both sides of the first region 113a and the first region 113a. The semiconductor layer 113 composed of the second region 113b is formed. In this case, a buffer layer (not shown) made of an inorganic insulating material, for example, silicon oxide (SiO ₂ ) or silicon nitride (SiNx) may be further formed between the semiconductor layer 113 and the first substrate 110. have. The buffer layer (not shown) is for preventing the deterioration of the characteristics of the semiconductor layer 113 due to the release of alkali ions from the inside of the first substrate 110, which is a glass material during crystallization of the semiconductor layer 113. .

In addition, a gate insulating layer 116 is formed on the entire surface of the semiconductor layer 113, and the gate electrode 116 is formed on the gate insulating layer 116 to correspond to the first region 113a of the semiconductor layer 113. 120 is formed. In addition, the gate insulating layer 116 is connected to a gate electrode (not shown) to form a switching thin film transistor (not shown), extends in one direction, and a gate wiring (not shown) is formed.

In addition, an interlayer insulating layer 123 is formed over the gate electrode 120 and the gate wiring (not shown). In this case, the interlayer insulating layer 123 and the gate insulating layer 116 thereunder are formed with a semiconductor layer contact hole 125 exposing each of the second regions 113b located on both sides of the first region 113a. .

Next, a data line (not shown) intersecting the gate line (not shown) and defining a pixel area (P) on the interlayer insulating layer 123 including the semiconductor layer contact hole 125 and a power source spaced apart from the power line. Wiring (not shown) is formed. In addition, the driving area DA and the switching area (not shown) are spaced apart from each other on the interlayer insulating layer 123 and contact the second area 113b exposed through the semiconductor layer contact hole 125, respectively. Drain electrodes 133 and 136 are formed. In this case, the semiconductor layer 113 including the source and drain electrodes 133 and 136, the second region 113b in contact with the electrodes 133 and 136, and a gate formed on the semiconductor layer 113. The insulating layer 116 and the gate electrode 120 form a driving thin film transistor DTr and a switching thin film transistor (not shown), respectively. In this case, the switching thin film transistor (not shown) is electrically connected to the driving thin film transistor DTr, the gate line (not shown), and the data line (not shown). The data line (not shown) is connected to a source electrode (not shown) of the switching thin film transistor (not shown).

In this case, the driving and switching thin film transistor DTr (not shown) forms a p-type or n-type thin film transistor according to an impurity doped in the second region 113b. In the case of the p-type thin film transistor, the second region 113b is formed by doping element 3, for example, boron (B), and holes are used as carriers.

Therefore, the first electrode 147 connected to the drain electrode 136 of the driving thin film transistor DTr serves as an anode or a cathode according to the type of the driving thin film transistor DTr. In the exemplary embodiment of the present invention, the first electrode 147 connected to the driving thin film transistor DTr serves as an anode electrode.

In addition, a first passivation layer 140 is formed on an entire surface of the driving and switching thin film transistor DTr (not shown). In this case, a drain contact hole 143 exposing the drain electrode 136 of the driving thin film transistor DTr is formed in the first passivation layer 140.

Although not shown in the drawings, a gate electrode (not shown) of the switching thin film transistor (not shown) is connected to the gate wiring (not shown), and a source electrode (not shown) of the switching thin film transistor (not shown) is It is connected to the data line (not shown).

In addition, the drain electrode 136 of the driving thin film transistor DTr is in contact with the drain contact hole 143 on the first passivation layer 140 including the drain contact hole 143. The first electrode 147 is formed for each pixel region P. FIG. At this time, although not shown in the drawing, it is preferable that the first electrode 147 has a double layer structure or a reflecting plate (not shown) is provided below the first electrode 147 in terms of maximizing light efficiency. That is, when the first electrode 147 forms a double layer structure, an upper layer (not shown) serves as an anode electrode, and a lower layer (not shown) is preferably formed of a conductive material that can serve as a reflector. Do.

In more detail, the upper layer (not shown) of the first electrode 147 has a relatively large work function value to serve as an anode electrode, and is a transparent conductive material such as indium tin oxide (ITO) or indium zinc. -Made of oxide (IZO), and the lower layer (not shown) of the first electrode 147 is made of a metal material having excellent reflection efficiency, for example, aluminum (Al) or silver (Ag), thereby providing the first electrode 147. By reflecting the light emitted from the organic light emitting layer 155 formed on the upper part to improve the luminous efficiency. Meanwhile, when the first electrode 147 is formed as shown in a single layer structure, a reflector (not shown) may be further formed below the first electrode 147 as a metal material having excellent reflection efficiency described above. have.

Next, a buffer pattern 150 is formed on the boundary of each pixel region P on the first electrode 147 so as to overlap the edge of the first electrode 147 in a form surrounding the pixel region P. have.

In addition, in each pixel area P surrounded by the buffer pattern 150, an organic emission layer 155 is formed on the first electrode 147, and an organic emission layer 155 is formed on the entire display area above the organic emission layer 155. 2 electrodes 158 are formed. In this case, the first and second electrodes 147 and 158 and the organic light emitting layer 155 formed therebetween form an organic light emitting diode (E).

Although not shown in the figure, a multilayer structure is formed between the first electrode 147 and the organic light emitting layer 155 and between the organic light emitting layer 155 and the second electrode 158 to improve the luminous efficiency of the organic light emitting layer 155, respectively. The first light emitting compensation layer (not shown) and the second light emitting compensation layer (not shown) may be further formed. In this case, the multilayer first emission compensation layer (not shown) is sequentially stacked from the first electrode 147 and includes a hole injection layer and a hole transporting layer. The light emitting compensation layer (not shown) includes an electron transporting layer and an electron injection layer from the organic light emitting layer 155. The first emission compensation layer (not shown) and the second emission compensation layer (not shown) of the multilayer structure may be formed in a plate shape on the entire surface of the display area, or may be separately formed for each pixel area (P). have.

On the other hand, the second electrode 158 formed on the organic light emitting layer 155 is a metal material having a relatively low work function value, such as aluminum (Al), aluminum so that the first electrode 147 serves as a cathode electrode One of the alloys (AlNd), silver (Ag), magnesium (Mg), gold (Au), aluminum magnesium alloy (AlMg) is characterized in that it is formed to have a thickness of about 10 ~ 200 Å to transmit light.

Next, the light efficiency of the organic light emitting layer 155 may be improved over the second electrode 158 formed on the entire display area, and the protection of the second electrode 158 and prevention of moisture penetration into the organic light emitting layer 155 may be prevented. The second protective layer 160 is formed of an inorganic insulating material or an organic insulating material.

Next, as the most characteristic configuration of the present invention, a touch-type second electrode 165 having a bar shape spaced apart from each other on the second protective layer 160 is formed. In this case, the spaced apart touch second electrode 165 is a touch sensor TS together with the second protective layer 160 disposed below the second protective layer 160 and the second electrode 158 (the touch first electrode) formed in front of the display area. ) Is a feature.

Accordingly, the second electrode 165 may be one component of the organic light emitting diode E and also may be one component of the touch sensor TS.

Next, the second substrate 170 for encapsulation of a transparent glass material or a transparent plastic material through an inert gas, an organic insulating material, or a face seal inside the touch second electrode 165 therein. By providing the touch sensor in-cell type organic light emitting device 101 according to the present invention.

In this case, a polarizer 175 may be further provided on the outer surface of the second substrate 170 to increase the efficiency of light emitted from the organic light emitting layer 155. Since the polarizer 175 is a mobile phone, a PDA, and a laptop, which are usually used mainly for personal use, the luminance characteristic at the front of the image is the most important, and thus selectively passes only light that is incident at a characteristic angle. After returning back to the lower part is reflected by a reflector (not shown) and serves to enter again at a specific angle to transmit. The polarizer 175 is not necessarily configured and may be omitted.

Meanwhile, in the touch sensor in-cell type organic light emitting device 101 according to the present invention having the above-described configuration, the touch sensor TS includes the second electrode 158, the second protective layer 160, and the touch. A capacitor formed of the second electrode 165 may be formed, and when a finger or the like comes into contact, the capacitor may recognize a change in capacitance caused by a change in the fringe field of the capacitor to act as a touch sensor TS.

6A to 6B are simplified cross-sectional views illustrating the operation of the touch sensor in the touch sensor in-cell type organic light emitting device according to the present invention. For convenience of description, the driving and switching thin film transistors and the organic light emitting diode are omitted, and only the touch sensor provided in the first substrate and the second substrate for encapsulation are briefly shown.

As shown in FIG. 6A, in the touch sensor in-cell type organic light emitting device 101 according to the present invention, when the user's finger 195 or the like is not touched on the surface of the second substrate 170, Since the fringe field formed between the second electrode 158 and the touch second electrode 165 is kept constant, there is no change in capacitance of the capacitor, and thus, the operation is not performed. As shown in FIG. 6B, the second substrate ( When a touch of the user's finger 195 or the like occurs on the surface of the 170, the second electrode 158 (the touch first electrode), the touch second electrode 165, and the fringe field are touched 195. The change occurs under the influence of the touch sensor, so that the touch sensor detects that the touch has been touched.

Meanwhile, referring to FIG. 5, the touch sensor in-cell type organic light emitting device 101 according to the present invention having the above-described configuration includes a second electrode 158 which is one component constituting the organic light emitting diode E. Referring to FIG. The second protective layer 160, which is used as a touch first electrode of the touch sensor TS and is formed on the upper portion thereof to prevent moisture permeation of the organic light emitting layer 155, is used as a dielectric layer, and the second protective layer is separately provided. After forming the touch second electrode 165 having a bar shape spaced apart on the layer 160, the second substrate 170 for encapsulation is bonded to each other.

Therefore, since the protective sheet and one substrate, the touch first electrode and the dielectric layer can be omitted, compared to the organic light emitting device having a touch sensor, the protective sheet, one substrate, and two material layers are omitted. The weight is reduced, and the process simplification is realized by omitting two material layers.

In this case, in the drawing, the touch second electrode 165 is illustrated as being formed in one pixel area in the display area. However, this is illustrated for convenience of description, and in reality, the touch second electrode ( 165) One pixel area P is characterized by being formed in a bar shape.

Meanwhile, the bar-shaped touch second electrode 165 does not necessarily need to be formed every one pixel region P, and mainly includes pixel regions in which red, green, and blue light emitting material layers 155 are formed, respectively. It is preferable to form only the pixel region P in which the light emitting material layer 155 of any of (P) is formed. Alternatively, in the case where the touch second electrode 165 is formed in one pixel area P, the touch second electrode 165 is not formed in one to ten pixel areas adjacent thereto. Ten pixel areas may be formed at a spaced interval.

The reason why the touch second electrode 165 is formed to have a predetermined beat interval is because the touch second electrode 165 and the lower second electrode 158 (the touch first electrode) must form a fringe field. This is because a touch is required on the panel surface, and a finger is used, and since the area of the touched finger corresponds to several to several tens of pixel areas, the touch second electrode 165 is a pixel area P unit. Even if the gaps are formed to be spaced apart from each other, the touch second electrode 165 is not formed in the touched area, so that a problem such as not detecting a touch does not occur.

7A and 7B illustrate a part of a plan view of a touch sensor in-cell type organic light emitting diode according to a modified example of the present invention.

As shown, the touch sensor in-cell type organic light emitting device according to the modification of the present invention has a white light emitting layer (not shown) in which the organic light emitting layer emits white in addition to the pixel areas R, G, and B that emit red, green, and blue light. Is configured to include the pixel region W provided with the eye.

As such, in the case of the touch sensor in-cell type organic light emitting device including four red, green, blue, and white pixel areas R, G, B, and W representing one color, the touch second electrode ( 165 is formed in the pixel region W in which an organic emission layer (not shown) emitting white light is formed.

The reason for forming the touch second electrode 165 corresponding to the pixel area W in which the white organic emission layer (not shown) is formed may be generated by forming the touch second electrode 165 configured to drive the touch sensor. This is to minimize the problem of luminance deterioration.

Even if the touch second electrode 165 is formed of a transparent conductive material, it does not transmit 100% of light emitted from the organic light emitting layer (not shown), and a decrease in transmittance occurs therein. Since the pixel region W emitting white light has the best luminance characteristic compared to the pixel regions R, G, and B emitting light, the touch second electrode 165 is formed in the pixel region W emitting white light. This is because the problem of luminance deterioration can be minimized.

Hereinafter, a method of manufacturing the touch sensor in-cell type organic light emitting device according to the present invention having the above-described configuration will be briefly described with reference to FIG. 5. In this case, since the method of forming the switching and driving thin film transistor is the same as the method of manufacturing a general array substrate, a method of forming an organic light emitting diode and a touch sensor will be described.

First, gate lines (not shown), data lines (not shown), and power lines (not shown) that cross each other are formed in the display area on the transparent glass or plastic insulating substrate 110, and each pixel area P is formed. A thin film transistor (not shown) connected to the gate and data lines (not shown) and a driving thin film transistor (DTr) connected to the switching thin film transistor (not shown) are formed on the substrate.

Next, a first passivation layer 140 having a drain contact hole 143 exposing the drain electrode 136 of the driving thin film transistor DTr is formed on the switching and driving thin film transistor DTr. .

Next, a first metal layer (not shown) is entirely formed by depositing a metal material having excellent reflection efficiency, for example, aluminum (Al) or silver (Ag), on the first protective layer having the drain contact hole. A transparent conductive material having a relatively large work function value, for example, indium tin oxide (ITO) or indium zinc oxide (IZO), is deposited over the metal layer (not shown) to form a transparent conductive material layer (not shown).

Subsequently, the transparent conductive material layer (not shown) and the first metal layer (not shown) include a photoresist, a mask including a series of unit processes such as exposure using an exposure mask, development of an exposed photoresist, etching and stripping, and the like. The patterning process is performed to form the reflective plate and the first electrode 147 in contact with the drain electrode 136 of the driving thin film transistor DTr through the drain contact hole 143 in each pixel region P. Referring to FIG.

Next, an inorganic insulating material, such as silicon oxide (SiO ₂ ) or silicon nitride (SiNx), is deposited on the first electrode 147 to form an inorganic insulating layer (not shown), and then patterned by performing a mask process. A buffer pattern 150 is formed to cover the end portion of the first electrode 147 in a form surrounding the pixel region P. Referring to FIG.

Next, a shadow mask having an open portion (OA) and a blocking portion (BA) is an organic light emitting material emitting red, green, and blue or an organic light emitting material emitting red, green, blue, and white on the buffer pattern 150. By sequentially depositing using 193, organic light of red, green, blue or red, green, blue, and white is formed on the first electrode 147 exposed to the outside of the buffer pattern 150 in each pixel region P. The light emitting layer 155 is formed.

In this case, although not shown in the drawing, before forming the red, green, and blue or red, green, blue, and white organic light emitting layers 155, the first electrode 147 in front of the display area or for each pixel area P is formed. A first light emitting compensation layer (not shown) of a hole injection layer and a hole transporting layer may also be formed. In this case, the organic emission layer 155 is formed on the first emission compensation layer (not shown).

Although not shown in the drawings, a second light emitting compensation layer including an electron transporting layer and an electron injection layer on the entire display area or each pixel area P is disposed on the organic light emitting layer 155. May be further formed).

 Next, a metal material having a relatively low work function value over the organic light emitting layer 155 or the second light emitting compensation layer (not shown), for example, aluminum (Al), aluminum alloy (AlNd), or silver (Ag). , By depositing one of magnesium (Mg), gold (Au), and aluminum magnesium alloy (AlMg) to have a thickness of about 10 μs to about 200 μs so that light emitted from the organic light emitting layer 155 may pass through. ). In this case, the organic light emitting layer 155 and the first electrode 147 disposed below the second electrode 158 formed on the entire display area form an organic light emitting diode (E). In addition, although the second electrode 158 may also be a component of the organic light emitting diode E, the second electrode 158 serves as a touch first electrode of the touch sensor TS.

Next, in order to maximize luminous efficiency by preventing the moisture permeation to the organic light emitting layer 155 and adjusting the light path, the second electrode 158 is deposited with an inorganic insulating material or by applying an organic insulating material to the entire surface of the display area. The second protective layer 160 is formed on the substrate. In this case, the second protective layer 160 serves as a dielectric layer of the touch sensor TS.

Next, a pixel region emitting red, green, and blue light by depositing and patterning a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO) on the second protective layer 160. When one of the pixel areas P or the pixel areas emitting white light is provided, the corresponding pixel areas P may be spaced apart from the white pixel areas or 1 to 10 pixel areas. A bar-shaped touch second electrode 165 is formed.

In this case, the second electrode 158 (the touch first electrode), the second protective layer 160, and the touch second electrode 165 formed on the entire display area form a touch sensor TS having a fringe field capacitance.

Next, a seal pattern (not shown) is formed along the outer edge of the display area with respect to the first substrate 110 including the organic light emitting diode E and the touch sensor TS, and is formed of a transparent glass material or a plastic material. By bonding the second substrate 170 in a vacuum or inert gas atmosphere, the touch sensor in-cell type organic light emitting device 101 according to the present invention may be completed.

At this time, between the second substrate 170 and the first substrate 110, in addition to the atmosphere of the inert gas or vacuum, a transparent face seal may be applied to the entire surface to form an adhesive layer.

In addition, the polarizing plate 175 is further configured on the outer surface of the second substrate 170 to selectively transmit only the light incident at a specific angle, and the remaining light toward the reflecting plate (not shown) on the first substrate 110. In order to reflect the light, the light may be continuously reflected to be incident on the polarizer 175 at a specific angle between the first substrate 110 and the second substrate 170 to maximize the luminous efficiency. .

1 is a circuit diagram of one pixel of a typical active matrix organic electroluminescent device.

2 is a schematic cross-sectional view of a conventional organic EL device.

3 is a cross-sectional view of one pixel area including a driving thin film transistor of a conventional top emission type organic light emitting device.

4 is a schematic cross-sectional view of an organic light emitting diode with a conventional touch sensor.

5 is a cross-sectional view of a touch sensor in-cell type organic light emitting device according to an exemplary embodiment of the present invention.

Figure 6a to 6b is a simplified cross-sectional view illustrating the operation of the touch sensor in the touch sensor in-cell type organic light emitting device according to the present invention.

7A and 7B are views respectively showing a plan view of a touch sensor in-cell type organic light emitting device according to a modification of the present invention;

<Explanation of symbols for main parts of the drawings>

101: touch sensor in-cell type organic light emitting device

110: first substrate 113: semiconductor layer

113a: first region 113b: second region

116: gate insulating film 120: gate electrode (of driving thin film transistor)

123: interlayer insulating film 125: semiconductor layer contact hole

133: source electrode (of the driving thin film transistor)

136: drain electrode (of driving thin film transistor)

140: first protective layer 143: drain contact hole

147: first electrode 150: buffer pattern

155: organic light emitting layer 158: second electrode (touch first electrode)

160: second protective layer 165: touch second electrode

170: second substrate 175: polarizing plate

DA: driving region E: organic light emitting diode

P: Pixel Area TS: Touch Sensor

Claims (10)

Display area A plurality of pixel areas are defined, and gate and data lines crossing each other, power lines, a switching thin film transistor connected to the gate and data lines, a driving thin film transistor connected to the switching thin film transistor, and an organic light emitting diode In the touch sensor in-cell type organic light emitting device comprising a first substrate comprising a transparent second substrate facing the same, A first electrode formed in each pixel area in contact with the drain electrode of the driving thin film transistor; A buffer pattern surrounding each pixel area and covering an edge of the first electrode; An organic emission layer formed on the first electrode in the pixel region; A second electrode formed over the organic light emitting layer on the entire display area; A first material layer formed over the second electrode and over the display area; And a touch electrode formed on the first layer to correspond to a plurality of specific pixel areas of the plurality of pixel areas, wherein the second electrode, the first material layer, and the touch electrode form a touch sensor. Sensor in-cell type organic light emitting device. The method of claim 1, The organic light emitting layer is composed of red, green, and blue organic light emitting materials, and the red, green, and blue organic light emitting layers are sequentially formed in each pixel area to emit red, green, and blue light, respectively. device. The method of claim 2, The specific pixel area may be a pixel area that emits any color among the pixel areas emitting red, green, and blue, or a pixel area disposed at a spacing interval of 1 to 10 pixel areas in the display area. Touch sensor in-cell type organic light emitting device characterized in that the. The method of claim 1, The specific pixel region may be a pixel region in which a white organic light emitting layer is formed to emit white light when the organic light emitting layer is formed of an organic light emitting material that sequentially emits red, green, blue, and white light in each pixel area. Touch sensor in-cell type organic light emitting device. The method of claim 1, Touch sensor in-cell type organic light emitting device, characterized in that the polarizing plate is configured on the outer surface of the second substrate. The method of claim 1, A reflector plate made of aluminum (Al) or silver (Ag) having excellent reflection efficiency is formed under the first electrode. The first electrode is made of indium tin oxide (ITO) or indium zinc oxide (IZO), which is a transparent conductive material having a large work function value to serve as an anode electrode. The second electrode is aluminum (Al), aluminum alloy (AlNd), silver (Ag), magnesium (Mg), gold (Au), aluminum magnesium, a metal material having a relatively low work function value to act as a cathode electrode Made of one of the alloys (AlMg), The touch electrode is a touch sensor in-cell type organic light emitting device, characterized in that made of indium tin oxide (ITO) or indium zinc oxide (IZO) transparent conductive material. The method of claim 6, A hole injection layer and a hole transporting layer are formed between the first electrode and the organic light emitting layer. And an electron transporting layer and an electron injection layer between the organic light emitting layer and the second electrode. A gate and data wiring crossing each other on a first substrate having a plurality of pixel regions defined in the display area, a power supply wiring, a switching thin film transistor connected to the gate and data wiring, and a driving thin film transistor connected to the switching thin film transistor. Forming; Forming a first protective layer having a drain contact hole exposing the drain electrode of the driving thin film transistor; Forming a first electrode on the first passivation layer in contact with the drain electrode of the driving thin film transistor through the drain contact hole in each pixel area; Forming a buffer pattern surrounding each pixel area and covering an edge of the first electrode; Forming organic light emitting layers on the first electrodes in the pixel areas, respectively; Forming a second electrode over the display area on the organic light emitting layer; Forming a second passivation layer over the second electrode, over the display area; Forming a touch electrode on the second passivation layer corresponding to a specific pixel area of each pixel area; Bonding the first substrate and the transparent second substrate to face the touch electrode; Method of manufacturing a touch sensor in-cell type organic light emitting device comprising a. The method of claim 8, The organic light emitting layer is formed of an organic light emitting material emitting red, green, and blue, and the pixel region is formed when the red, green, and blue organic light emitting layers are sequentially formed to emit red, green, and blue, respectively. The specific pixel region may be a pixel region emitting one of the red, green, and blue pixel regions, or may be a pixel region arranged to have a spacing interval of 1 to 10 pixel regions. Alternatively, the organic light emitting layer includes an organic light emitting material that emits white in addition to red, green, and blue, and the pixel region is formed by sequentially forming red, green, blue, and white organic light emitting layers, respectively, red, green, blue, and white. In the case of emitting light, the specific pixel area is a manufacturing method of the touch sensor in-cell type organic light emitting device, characterized in that the pixel area for emitting the white light. The method of claim 8, Method of manufacturing a touch sensor in-cell type organic light emitting device comprising attaching a polarizing plate on the outer surface of the second substrate.

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