KR20190015159A - Touch sensor in-cell type organic electroluminesence device - Google Patents

Abstract

The present invention relates to a touch sensor in-cell type organic electroluminescent device having reduced thickness due to omission of a separate touch panel. The touch sensor in-cell type organic electroluminescent device according to an embodiment of the present invention includes: at least one OLED-driving Thin-Film Transistor (OLED driving TFT) that is formed on a substrate and drives an organic light emitting device (OLED); the OLED connected to the at least one OLED driving TFT through a first contact hole; at least one touch-sensing thin-film transistor (touch sensing TFT) that is simultaneously formed with the at least one OLED driving TFT on the substrate and senses touch; and a touch electrode that is connected to the at least one touch sensing TFT through a second contact hole and does not overlap with the OLED, wherein the at least one OLED driving TFT and the at least one touch sensing TFT share a gate line.

Description

TOUCH SENSOR IN-CELL TYPE ORGANIC ELECTROLUMINESENCE DEVICE [0002]

Embodiments of the present invention relate to a cell-type organic electroluminescent device which is a touch sensor, and more particularly to a cell-type organic electroluminescent device which is a touch sensor with a reduced thickness by omitting a separate touch panel.

2. Description of the Related Art [0002] As an information-oriented society develops, there have been various demands for display devices for displaying images. Recently, liquid crystal displays (LCDs), plasma display panels (PDPs) Various display devices such as an OLED (Organic Light Emitting Diode Display Device) and the like are being utilized.

An organic light-emitting diode (OLED) display device, which is one of flat panel display devices (FPDs), has a better viewing angle and contrast than a liquid crystal display device because it is self-emitting type, Therefore, it is possible to make a light-weight thin type, and it is also advantageous in terms of power consumption. Also, because it can be driven by DC low voltage, has a fast response speed, and is solid, it is resistant to external impact, has a wide temperature range, and is especially advantageous in terms of manufacturing cost.

On the other hand, a touch-type display device capable of selecting a screen of a video display device as a human hand or an object and inputting a user command is widely used.

To this end, a touch-type display device is provided with a touch panel on a front surface of a video display device, and converts a position directly touching a human hand or an object into an electrical signal. Thus, the instruction content selected at the contact position is supplied as an input signal.

As a method of implementing such a touch panel, a resistive type, a light sensing type, and a capacitive type are known. The dual volumetric capacitive touch panel senses the change in capacitance that a conductive sensing pattern forms with other surrounding sensing patterns when a human hand or object is touched.

Such a touch panel is implemented by an add-on method in which a separate touch panel is formed on an organic light emitting diode display device.

However, such an add-on type touch-type light-emitting diode display device is problematic in that the thickness of the entire display device is increased by the touch panel and the manufacturing cost is increased by a separate substrate required for the touch panel formation process and the touch panel have.

Korean Patent Publication No. 10-2015-0130620, " Touch Screen Panel Integrated Display Device and Manufacturing Method " Korean Patent No. 10-1588450, " Touch Sensor In-Cell Type Organic EL Device " Korean Patent No. 10-1589272, " Touch Sensor In-Cell Type Organic Electroluminescent Device and Manufacturing Method Thereof "

It is an object of embodiments of the present invention to provide a touch sensor which is integrated with a back plane substrate of an organic electroluminescent device and omits a separate touch panel to reduce the thickness and manufacturing cost of the display device, And to manufacture an electroluminescent device.

It is an object of embodiments of the present invention to provide an OLED driving TFT and a touch sensing thin film transistor that share a gate line to drive an organic light emitting device and a touch sensing with a single driver Cell type organic electroluminescent device with reduced manufacturing cost and simplification.

The organic electroluminescent device of the cell type of a touch sensor according to an embodiment of the present invention includes at least one OLED driving TFT (not shown) formed on a substrate and driving an organic light emitting device (OLED) ); The organic light emitting device connected to the at least one OLED driving transistor through a first contact hole; At least one touch sensing thin film transistor (TFT) formed simultaneously with the at least one OLED driving thin film transistor on the substrate and sensing a touch; And a touch electrode connected to the at least one touch sensing thin film transistor through a second contact hole and not overlapped with the organic light emitting element, wherein the at least one OLED driving thin film transistor and the at least one touch sensing thin film transistor Share a gate line.

The touch sensing thin film transistor includes: a gate electrode formed on the substrate; A gate insulating film formed on the gate electrode; A semiconductor layer formed on the gate insulating film; Source / drain electrodes formed on the semiconductor layer and spaced apart from each other; A passivation layer formed on the source / drain electrode; And a though electrode formed on the passivation layer and connected to the drain electrode through a second contact hole, and the touch electrode may be formed on the organic light emitting layer of the organic light emitting device.

The touch sensing thin film transistor includes: a gate electrode formed on the substrate; A gate insulating film formed on the gate electrode; A semiconductor layer formed on the gate insulating film; Source / drain electrodes formed on the semiconductor layer and spaced apart from each other; A passivation layer formed on the source / drain electrode; And a touch electrode formed on the passivation layer and connected to the drain electrode through a second contact hole, and the touch electrode may be formed under the organic light emitting layer of the organic light emitting device.

The in-cell type organic electroluminescent device includes an emission area formed with the organic light emitting device and a touch electrode area formed with the touch electrode, The area may be less than 50% of the display area.

The emission area may be less than 50% of the display area.

The touch capacitance minimum value of the touch electrode may be 0.1 pF to 2 pF.

The minimum size of the touch electrode may be ² X ² mm ² or less.

The organic electroluminescent device of the in-cell type according to an embodiment of the present invention includes at least one display pixel including an organic light emitting device and at least one OLED driving TFT; And at least one touch sensing circuit including at least one touch sensing thin film transistor connected to the touch electrode, wherein the at least one touch sensing circuit comprises a side portion of the at least one display pixel ).

The at least one OLED drive thin film transistor and the at least one touch sensing thin film transistor may share a gate line.

 The touch sensing circuit may include a first touch sensing thin film transistor, a second touch sensing thin film transistor, and a capacitor.

The touch sensing circuit may include a first touch sensing thin film transistor, a second touch sensing thin film transistor, a third touch sensing thin film transistor, a fourth touch sensing thin film transistor, and a capacitor.

The touch sensing circuit may be driven by sharing a gate driver for driving a display pixel.

The touch sensing circuit may be driven by sharing a data driver for driving a display pixel.

A display device according to an embodiment of the present invention includes a touch sensor of a cell type organic electroluminescent device according to an embodiment of the present invention.

According to embodiments of the present invention, the thickness of the display device and the manufacturing cost can be reduced by omitting a separate touch panel by integrating the touch sensor on the back plane substrate of the organic electroluminescent device.

According to embodiments of the present invention, the OLED driving TFT and the touch sensing thin film transistor are formed so as to share a gate line, and an organic light emitting device (display) and touch sensing are driven by a single driver, Can be reduced.

1A to 1C are cross-sectional views illustrating a touch sensor of a cell type organic electroluminescent device according to an embodiment of the present invention.
FIGS. 2A to 2D are plan views illustrating a light emitting region and a touch electrode region of a cell-type organic electroluminescent device according to embodiments of the present invention.
3 is a three-dimensional view illustrating a display pixel and a touch sensing circuit of a cell-type organic electroluminescent device, which is a touch sensor according to embodiments of the present invention.
FIG. 4 is a plan view showing a cell-type organic electroluminescent device as a touch sensor according to embodiments of the present invention.
5A is a circuit diagram illustrating a touch sensing circuit of a 2T1C included in a touch sensor of a cell type organic electroluminescent device according to embodiments of the present invention.
5B is a timing diagram graph showing a change in output voltage of a touch sensing circuit included in a cell type organic electroluminescent device, which is a touch sensor according to embodiments of the present invention, according to a touch / to be.
6 is a circuit diagram illustrating a 4T1C touch sensing circuit included in a touch sensor of a cell type organic electroluminescent device according to embodiments of the present invention.
FIGS. 7A and 7B are views showing an organic electroluminescent device of a-cell type, which is a touch sensor according to embodiments of the present invention, according to the size of the touch sensing circuit.
8 is an image showing a single touch sensing circuit included in a cell-type organic electroluminescent device, which is a touch sensor according to embodiments of the present invention.
9A to 9C are timing diagram graphs illustrating changes in output voltage of a touch sensing circuit included in a cell type organic electroluminescent device according to embodiments of the present invention, to be.
FIGS. 10A to 10C are timing diagrams illustrating changes in output voltage of a touch sensing circuit included in a cell-type organic electroluminescent device, which is a touch sensor according to embodiments of the present invention, Graph.
11 is an image showing a touch sensing circuit and a scan driver of a cell-type organic electroluminescent device, which is a touch sensor according to embodiments of the present invention, 8X8.
FIG. 12 is a timing diagram showing a voltage change of a touch sensing circuit of a cell-type organic electroluminescent device which is a touch sensor according to embodiments of the present invention of 8 × 8 according to a touched point.
FIG. 13 is a graph showing a voltage difference of a touch sensing circuit of a cell-type organic electroluminescent device, which is a touch sensor according to embodiments of the present invention of 8X8 in a touch / untouched state.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings and accompanying drawings, but the present invention is not limited to or limited by the embodiments.

The terminology used herein is for the purpose of illustrating embodiments and is not intended to be limiting of the present invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. It is noted that the terms "comprises" and / or "comprising" used in the specification are intended to be inclusive in a manner similar to the components, steps, operations, and / Or additions.

As used herein, the terms "embodiment," "example," "side," "example," and the like should be construed as advantageous or advantageous over any other aspect or design It does not.

Also, the term 'or' implies an inclusive or 'inclusive' rather than an exclusive or 'exclusive'. That is, unless expressly stated otherwise or clear from the context, the expression 'x uses a or b' means any of the natural inclusive permutations.

Also, the phrase " a " or " an ", as used in the specification and claims, unless the context clearly dictates otherwise, or to the singular form, .

The terms used in the following description are chosen to be generic and universal in the art to which they are related, but other terms may exist depending on the development and / or change in technology, customs, preferences of the technician, and the like. Accordingly, the terminology used in the following description should not be construed as limiting the technical thought, but should be understood in the exemplary language used to describe the embodiments.

Also, in certain cases, there may be a term chosen arbitrarily by the applicant, in which case the detailed description of the meaning will be given in the corresponding description section. Therefore, the term used in the following description should be understood based on the meaning of the term, not the name of a simple term, and the contents throughout the specification.

On the other hand, the terms first, second, etc. may be used to describe various elements, but the elements are not limited by terms. Terms are used only for the purpose of distinguishing one component from another.

It will also be understood that when an element such as a film, layer, region, configuration request, etc. is referred to as being "on" or "on" another element, And the like are included.

Unless defined otherwise, all terms (including technical and scientific terms) used herein may be used in a sense commonly understood by one of ordinary skill in the art to which this invention belongs. Also, commonly used predefined terms are not ideally or excessively interpreted unless explicitly defined otherwise.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. The terminology used herein is a term used for appropriately expressing an embodiment of the present invention, which may vary depending on the user, the intent of the operator, or the practice of the field to which the present invention belongs. Therefore, the definitions of these terms should be based on the contents throughout this specification.

Hereinafter, a touch sensor in-cell type organic electroluminescent device according to embodiments of the present invention will be described with reference to FIGS. 1A to 1C.

1A to 1C are cross-sectional views illustrating a touch sensor of a cell type organic electroluminescent device according to embodiments of the present invention.

The organic electroluminescent device of the cell type of the touch sensor according to the embodiment of the present invention is formed on the substrates 110, 210 and 310 and includes organic light emitting devices (OLEDs) 170, 270 and 270 And OLED driving transistors (101, 201, 301) connected to at least one OLED driving transistor (101, 201, 301) through a first contact hole (H1) and at least one OLED driving TFT And includes light emitting devices 170, 270, and 270.

In addition, at least one touch sensing TFT (102, 202) formed simultaneously with the at least one OLED driving TFT (101, 201, 301) on the substrate (110, 210, 310) And the touch electrode 180 connected to the at least one touch sensing thin film transistor 102 through the first contact hole 302 and the second contact hole H2 and not overlapping the organic light emitting elements 170,

The at least one OLED driving thin film transistor 101 and the at least one touch sensing thin film transistor 102 share a gate line to form a single driver By driving the device (display) and touch sensing, driver process simplification and manufacturing cost can be reduced.

The technique of sharing at least one OLED driving thin film transistor 101, 201, 301 and at least one touch sensing thin film transistor 102, 202, 302 in a gate line is described in more detail in FIG. do.

Further, the touch sensor of the in-cell type organic electroluminescent device according to the embodiment of the present invention integrates the touch sensor on the back plane substrate and omits a separate touch panel, thereby reducing the thickness and manufacturing cost of the display device .

The backplane substrate means that the structure of the driving thin film transistor and the storage capacitor has been completed. The backplane substrate can be used not only for the organic light emitting device but also for the liquid crystal display device and other display devices.

Further, according to the embodiment, at least one OLED driving thin film transistor 101, 201, 301 and at least one touch sensing thin film transistor 102, 202, 302 shown in Figs. 1A to 1C are inverted, Or a co-planar structure.

A thin film transistor having an invert structure has a structure in which a gate electrode is attached to a substrate, and a thin film transistor having a coplanar structure has a structure in which source / drain electrodes, a gate insulating film, and a gate electrode are formed on a semiconductor layer.

In addition, at least one OLED driving thin film transistor 101 and at least one touch sensing thin film transistor 102 of a touch sensor in-cell type organic electroluminescent device according to an embodiment of the present invention are simultaneously formed by the same process.

More specifically, the touch sensor in-cell type organic electroluminescent device according to an embodiment of the present invention includes a first contact hole H1 on at least one OLED drive thin film transistor 101, And the step of forming the touch electrode 180 using the second contact hole H2 on the at least one touch sensing thin film transistor 102 may be performed on the substrate 110 by the same process Can be formed at the same time.

In addition, at least one OLED driving thin film transistor 101 and at least one touch sensing thin film transistor 102 of the in-cell type organic electroluminescent device according to the embodiment of the present invention are simultaneously formed by the same process, The process can be simplified, and the process cost can be reduced.

In addition, a touch sensor of a cell type organic electroluminescent device according to an embodiment of the present invention is used as a display device.

FIGS. 1A to 1C are cross-sectional views illustrating a touch sensor according to an exemplary embodiment of the present invention. Referring to FIG. 1A, I will explain.

1A is a cross-sectional view illustrating an organic electroluminescent device of a touch sensor of a cell type according to a first embodiment of the present invention.

The substrate 110 may be a substrate for supporting at least one OLED driving thin film transistor 101 and at least one touch sensing thin film transistor 102. A flexible substrate may be used, For example, the substrate 110 may be folded in the lateral direction, the longitudinal direction, or the diagonal direction.

Preferably, the substrate 110 is formed of a material selected from the group consisting of silicon, glass, polyester, polyvinyl, polycarbonate, polyethylene, polyacetate, polyimide, And may include at least one of polyethersulphone (PES), polyacrylate (PAR), polyethylene naphthalate (PEN), and polyethylene ether phthalate (PET).

A gate electrode 120 is formed on the substrate 110.

The gate electrode 120 may be formed by depositing a gate conductive film (not shown), forming a photoresist pattern on the gate conductive film, and then selectively etching (patterning) the gate conductive film using the photoresist pattern as a mask have.

The gate electrode 120 may include a metal or a metal oxide, which is an electrically conductive material. Specifically, the gate electrode 120 may be formed of at least one selected from the group consisting of Mo, Al, Cr, Au, Ti, (Cu), a metal oxide such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide) or ITZO (Indium Tin Zinc Oxide), or a combination thereof. Do not.

In addition, the gate electrode 120 may be formed as a single layer or a multi-layer structure including the above-described materials.

A gate insulating layer 130 is formed on the gate electrode 120 to insulate the gate electrode 120 from the semiconductor layer 140.

The gate insulating film 130 may be formed of an inorganic material such as silicon oxide (SiOx), silicon nitride (SiNx), titanium oxide (TiOx), or hafnium oxide (HfOx), or polyvinyl alcohol (PVA), polyvinylpyrrolidone Organic materials such as polymethylmethacrylate (PMMA) may be used, but the present invention is not limited thereto.

The gate insulating layer 130 may be formed of a single layer or a multi-layer structure including the above-described material, and the gate insulating layer 130 may be formed using a deposition method or a coating method.

A semiconductor layer 140 is formed on the gate insulating layer 130.

The semiconductor layer 140 may be formed on the gate insulating layer 130 to form a semiconductor film for forming the semiconductor layer 140 and then form a photoresist pattern and pattern the semiconductor film using the photoresist pattern as a mask. .

In addition, the semiconductor layer 140 may include a channel region in which a channel is formed and a source / drain region connected to the source / drain electrodes 151 and 152, respectively.

The semiconductor layer 140 may include at least one selected from the group consisting of low temperature polycrystalline silicon (LTPS), indium gallium zinc oxide (IGZO), zinc oxide (ZnO), indium zinc oxide (IZO), indium tin oxide (ITO), zinc tin oxide But is not limited to, at least one of zirconium oxide (ZTO), gallium zinc oxide (GZO), hafnium indium zinc oxide (HIZO), zinc indium tin oxide (ZITO) and aluminum zinc oxide (AZTO).

In addition, the semiconductor layer 140 may be formed of amorphous or polycrystal including the above-described materials.

In addition, the semiconductor layer 140 may be formed through chemical vapor deposition (CVD) or physical vapor deposition (PVD) methods.

Source / drain electrodes 151 and 152 are formed on the semiconductor layer 140.

The source electrode 151 and the drain electrode 152 may be spaced apart from each other on the semiconductor layer 140 and may be electrically connected to the semiconductor layer 140.

The source / drain electrodes 151 and 152 are formed by depositing a conductive film (hereinafter, a source / drain conductive film) for forming the source / drain electrodes 151 and 152 and forming a photoresist pattern on the source / drain conductive film And then patterning the source / drain conductive film using the photoresist pattern as a mask.

The source / drain electrodes 151 and 152 may be formed of a metal material such as molybdenum, aluminum, chromium, gold, titanium, ), Neodymium (Nd), and copper (Cu), or a combination thereof. However, the present invention is not limited thereto.

Further, the source / drain electrodes 151 and 152 may be formed as a single layer or a multi-layer structure including the above-described material.

Passivation layers 161, 162, and 163 164 are formed on the source / drain electrodes 151 and 152, respectively.

Preferably, the passivation layer 161, 162, 163 164 includes a first passivation layer 161 protecting at least one OLED drive thin film transistor 101 and at least one touch sensing thin film transistor 102, A second passivation layer 162 for planarizing the surfaces of the OLED driving thin film transistor 101 and the at least one touch sensing thin film transistor 102 and a second passivation layer 162 serving as a bank for exposing the light emitting region including the organic light emitting element 170 3 passivation layer 163 and a fourth passivation layer 164 protecting at least one OLED drive thin film transistor 101 and at least one touch sensing thin film transistor 102.

The first passivation layer 161 may be formed on the source / drain electrodes 151 and 152 and may protect at least one OLED driving thin film transistor 101 and at least one touch sensing thin film transistor 102.

The first passivation layer 161 may be formed of an inorganic or polyvinyl alcohol (PVA) such as silicon oxide (SiOx), silicon nitride (SiNx), titanium oxide (TiOx) or hafnium oxide (HfOx), polyvinylpyrrolidone ) Or polymethyl methacrylate (PMMA) may be used, but the present invention is not limited thereto.

Further, the first passivation layer 161 may be formed of a single layer or a multi-layer structure including the above-described materials.

A second passivation layer 162 is formed on the first passivation layer 161 to planarize at least one OLED driving TFT 101 and at least one touch sensing TFT 102.

The second passivation layer 162 may be formed of an inorganic or polyvinyl alcohol (PVA) such as silicon oxide (SiOx), silicon nitride (SiNx), titanium oxide (TiOx) or hafnium oxide (HfOx), polyvinylpyrrolidone ) Or polymethyl methacrylate (PMMA) may be used, but the present invention is not limited thereto.

In addition, the second passivation layer 162 may be formed as a single layer or a multi-layer structure including the above-described materials.

A first contact hole H1 is formed on the second passivation layer 162 to connect the drain electrode of at least one OLED driving TFT 101 with the OLED 170 formed in the subsequent process.

The first contact hole H1 is formed by etching the first and second passivation layers 161 and 162 and the first contact hole H1 is connected to the organic light emitting layer 172 of the organic light emitting device 170 OLED anode < RTI ID = 0.0 > 171 < / RTI >

The OLED anode 171 may be formed by depositing an electrically conductive material in the first contact hole H1 and then selectively etching (patterning) the electrically conductive material using the photoresist pattern as a mask.

Thus, the OLED anode 171 may be formed in the first contact hole H1 and on the surface of the second passivation layer 162. [

The OLED anode 171 may include a metal or a metal oxide, which is an electrically conductive material. Specifically, a metal such as Mo, Al, Cr, Au, Ti or Ag, Ni, Ne, And a metal oxide such as Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO) or Indium Tin Zinc Oxide (ITZO), or a combination thereof. However, the present invention is not limited thereto.

A third passivation layer 163 serving as a bank for exposing the organic light emitting layer 170 is formed on the second passivation layer 162.

The third passivation layer 163 may be formed to define the organic light emitting device 170 in the light emitting region and the third passivation layer 163 may be formed such that a portion thereof has a relatively protruding portion.

The organic light emitting device 170 includes an OLED anode 171, an OLED cathode 173 opposed to the OLED cathode 171, and an organic light emitting layer 173 disposed between the OLED anode 171 and the OLED cathode 173. [ Lt; / RTI >

1A is a schematic cross-sectional view of an OLED display device according to an exemplary embodiment of the present invention. Referring to FIG. 1A, the OLED anode 171, the organic emission layer 172, and the OLED anode 173 are sequentially formed. Can be sequentially formed.

The OLED anode 171 may further include an electron transporting layer or an electron injection layer between the OLED anode 171 and the organic emission layer 172, 173 may further include a hole injection layer or a hole transporting layer.

The OLED cathode 173 is formed on the third passivation layer 163 and the organic light emitting layer, and the OLED anode 171 may include a metal or a metal oxide which is an electrically conductive material. Specifically, a metal such as Mo, Al, Cr, Au, Ti or Ag, Ni, Ne, And a metal oxide such as Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO) or Indium Tin Zinc Oxide (ITZO), or a combination thereof. However, the present invention is not limited thereto.

The third passivation layer 163 includes a second contact hole H2 for connecting at least one touch sensing thin film transistor 102 to the touch electrode 180. [

The second contact hole H2 may be formed by etching the first to third passivation layers 161 to 163.

After depositing an electrically conductive material in the second contact hole H2, the electrically conductive material may be selectively etched (patterned) using the photoresist pattern as a mask.

An electric conductive material is deposited in the second contact hole H2 and then selectively etched (patterned) using the photoresist pattern as a mask to form the drain electrode 152 of the at least one touch sensing thin film transistor 102 The touch electrode 180 is formed.

Accordingly, the touch electrode 180 may be formed in the second contact hole H2 and on the third passivation layer 163.

The touch electrode 180 may be formed on the third passivation layer 163 by connecting the touch electrode 180 to the at least one touch sensing thin film transistor 102 using the second contact hole H2 .

The touch electrode 180 may be formed of a metal such as molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti) or silver (Ag), nickel (Ni), neodymium Cu, or a metal oxide such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), ITZO (Indium Tin Zinc Oxide), or the like, or a combination thereof. .

Also, according to the embodiment, the touch electrode 180 and the OLED cathode 173 may be formed by the same process after forming the second contact hole H2 to simplify the process.

1A, a touch electrode 180 of a touch sensor in-cell type organic electroluminescent device according to a first embodiment of the present invention may be formed on an organic light emitting layer 172 of an organic light emitting device 170 have.

Therefore, the touch electrode 180 of the in-cell type organic electroluminescent device according to the first embodiment of the present invention can be formed on the same layer as the OLED cathode 173 of the organic light emitting device 170, The touch electrode 180 does not overlap with the organic light emitting element 170.

More specifically, the touch electrode 180 may be formed on the third passivation layer 163 (bank), and the touch electrode 180 may be formed outside the region where the organic light emitting device 170 is formed, It is possible to prevent the device 170 and the touch electrode 180 from interacting with each other to reduce electrical or optical characteristics.

Accordingly, the touch sensor 180 according to the first embodiment of the present invention can improve the transmittance because the touch electrode 180 is not formed on the pixel electrode (not shown).

The touch capacitance minimum value of the touch electrode 180 may be 0.1 pF to 2 pF. If the minimum touch capacitance value is less than 0.1 pF, there is a problem that the sensing signal is small and the noise increases. There is a problem with the yield in expressing the value.

The minimum size of the touch electrode 180 can be equal to or less than 2X2mm ^2, the minimum size of adequate capacitance, the touch electrode 180 in order to preferably make a 0.1pF for sensing a touch is to be made of a less 2X2mm ^2.

Preferably, the minimum size of the touch electrode 180 may be 1.3 x 1.3 mm ² .

A fourth passivation layer 164 is formed on the third passivation layer 163 on which the OLED anode 171 and the touch electrode 180 are formed.

The fourth passivation layer 164 may be formed of an inorganic or polyvinyl alcohol (PVA) such as silicon oxide (SiOx), silicon nitride (SiNx), titanium oxide (TiOx) or hafnium oxide (HfOx), polyvinylpyrrolidone ) Or polymethyl methacrylate (PMMA) may be used, but the present invention is not limited thereto.

In addition, the fourth passivation layer 164 may be formed as a single layer or a multi-layer structure including the above-described materials.

1B is a cross-sectional view illustrating a touch sensor of a cell-type organic electroluminescent device according to a second embodiment of the present invention.

1B includes the same components as those in FIG. 1A except that the position of the touch electrode 280 is formed on the organic light emitting diode 270 and the fourth passivation layer 264, .

The touch electrode 280 is formed on the fourth passivation layer 264 and the touch electrode 280 is electrically connected to the organic light emitting device 270 ).

Therefore, in order to connect the at least one touch sensing thin film transistor 202 and the touch electrode 280, the in-cell type organic electroluminescent device according to the second embodiment of the present invention includes first through fourth passivation The layers 261 to 264 may be etched to form the second contact holes H2.

The second contact hole H2 is formed by etching the first to fourth passivation layers 261 to 264, and after depositing an electroconductive material in the second contact hole H2, using the photoresist pattern as a mask The electrically conductive material can be selectively etched (patterned).

Accordingly, the touch electrode 280 may be formed in the second contact hole H2 and on the fourth passivation layer 264.

The touch electrode 280 may be formed on the fourth passivation layer 264 by connecting the touch electrode 280 to the at least one touch sensing thin film transistor 202 using the second contact hole H2 .

The touch electrode 280 may be formed of a metal such as molybdenum, aluminum, chromium, gold, titanium or silver, nickel, Cu, or a metal oxide such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), ITZO (Indium Tin Zinc Oxide), or the like, or a combination thereof. .

Referring to FIG. 1B, the touch electrode 280 may be formed on the organic light emitting layer 272 of the organic light emitting diode 270.

More specifically, the touch electrode 280 is formed on the fourth passivation layer 264 and outside the region where the organic light emitting device 270 is formed, so that the organic light emitting device 270 and the touch electrode 280 Can be prevented from interacting with each other to reduce the electrical or optical characteristics.

Therefore, in the organic electroluminescent device of the cell type of the touch sensor according to the second embodiment of the present invention, the touch electrode 280 is not formed on the pixel electrode (not shown), so that the transmittance can be improved.

1C is a cross-sectional view illustrating an organic electroluminescent device of a touch sensor of a cell type according to a third embodiment of the present invention.

1C includes the same components as those of FIG. 1A except that the position of the touch electrode 380 is formed below the organic light emitting layer 372 of the organic light emitting device 370. Therefore, do.

Therefore, in order to connect the at least one touch sensing thin film transistor 302 and the touch electrode 380, the in-cell type organic electroluminescent device according to the third embodiment of the present invention includes first and second passivation The second contact holes H2 can be formed by etching the layers 361 and 362.

The second contact hole H2 is formed by etching the first and second passivation layers 361 and 362. After depositing an electrically conductive material in the second contact hole H2, The conductive material can be selectively etched (patterned).

Accordingly, the touch electrode 380 may be formed in the second contact hole H2 and on the second passivation layer 362. [

The touch electrode 380 may be formed on the second passivation layer 362 by connecting the touch electrode 380 to the at least one touch sensing thin film transistor 302 using the second contact hole H2 .

The touch electrode 380 may be formed of a metal such as molybdenum, aluminum, chromium, gold, titanium or silver, nickel, Cu, or a metal oxide such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), ITZO (Indium Tin Zinc Oxide), or the like, or a combination thereof. .

Referring to FIG. 1C, the touch electrode 380 may be formed under the organic light emitting layer 372 of the organic light emitting device 370.

Therefore, the touch electrode 380 of the in-cell type organic electroluminescent device according to the third embodiment of the present invention can be formed in the same layer as the OLED cathode 373 of the organic light emitting device 370, The touch electrode 380 does not overlap with the organic light emitting element 370. [

More specifically, the touch electrode 380 is formed on the second passivation layer 362, and is formed outside the region where the organic light emitting device 370 is formed, so that the organic light emitting device 370 and the touch electrode 380 Can be prevented from interacting with each other to reduce the electrical or optical characteristics.

Accordingly, the touch sensor 380 of the in-cell type organic electroluminescent device according to the third embodiment of the present invention can improve the transmittance by not forming the touch electrode 380 on the pixel electrode (not shown).

In order to simplify the process, the first contact holes H1 and H2 are formed in the same process as the in-cell type organic electroluminescent device according to the third embodiment of the present invention, The OLED cathode 373 and the touch electrode 380 can be formed.

FIGS. 2A to 2D are plan views illustrating a light emitting region and a touch electrode region of a cell-type organic electroluminescent device according to embodiments of the present invention.

Referring to FIG. 2A, a touch sensor of a touch sensor according to embodiments of the present invention includes an emission area 401 in which an organic light emitting diode is formed, a touch electrode area 402, as shown in FIG.

The touch electrode area 402 may include at least one touch electrode having various shapes and sizes, and the touch electrode area 402 may be 50% or less of the display area.

The touch electrodes having various shapes and sizes included in the touch electrode area 402 will be described with reference to FIGS. 2B to 2D.

The emission region 401 includes at least one organic light emitting device as a region through which light is emitted through the organic light emitting device and the emission region 401 includes red (R), green G), blue (B), and white (W).

Emissive area 401 may be less than 50% of the display area.

The touch electrode region 402 may be formed so as not to overlap the emission region 401 and the touch electrode region 402 may be formed so as not to overlap the emission region 401, It is possible to prevent the touch electrodes from interacting with each other to reduce electrical or optical characteristics.

Referring to FIG. 2B, a touch electrode of a touch sensor of a cell-type organic electroluminescent device according to embodiments of the present invention may include only an organic light emitting device of one of RGB.

Accordingly, the touch electrode region 402 may include a plurality of touch electrodes including only organic light emitting elements of one of RGB.

Referring to FIG. 2C, the touch electrode of the in-cell type organic electroluminescent device according to embodiments of the present invention may include all the organic light emitting devices of RGB colors.

Accordingly, the touch electrode region 402 may include a plurality of touch electrodes including all organic light emitting elements of RGB colors.

Referring to FIG. 2D, the touch electrode of the in-cell type organic electroluminescent device according to embodiments of the present invention may include a plurality of RGB organic light emitting devices.

Therefore, the touch electrode region 402 may include a plurality of touch electrodes including all the organic light emitting elements of RGB colors.

Therefore, referring to FIGS. 2A to 2D, the touch sensor of the in-cell type organic electroluminescent device according to the embodiments of the present invention can manufacture touch electrodes having various structures.

3 is a three-dimensional view illustrating a display pixel and a touch sensing circuit of a cell-type organic electroluminescent device, which is a touch sensor according to embodiments of the present invention.

Cell type organic electroluminescent device according to embodiments of the present invention includes at least one display pixel 510 and at least one touch electrode 522 including an organic light emitting device and at least one OLED driving thin film transistor, And at least one touch sensing circuit (520) including at least one touch sensing thin film transistor connected to the sensing circuit (520).

Also, at least one touch sensing circuit 520 may be formed on a side portion of at least one display pixel 510.

At least one OLED driving TFT of at least one display pixel 510 and at least one touch sensing TFT of at least one touch sensing circuit 520 may share a gate line 512 can do.

The display pixel 510 includes a pixel data line 511 and at least one gate line 512 connected to the pixel data line 511 and the gate line 512 within a pixel region defined by intersecting the pixel data line 511 and the gate line 512 on the substrate. OLED driving thin film transistors.

The source electrode or the drain electrode of at least one OLED driving thin film transistor may be connected to the pixel data line 511 and the gate electrode may be connected to the gate line 512.

The touch sensing circuit 520 is formed to intersect the touch sensor data line 521 and the gate line 512 so that the touch sensor data line 521 and the gate line 512 And at least one touch sensing thin film transistor connected thereto.

The source electrode or the drain electrode of at least one touch sensing thin film transistor may be connected to the touch sensor data line 521 and the gate electrode may be connected to the gate line 512.

Accordingly, at least one OLED driving TFT and at least one touch sensing TFT are connected to the same gate line to drive an organic light emitting device (display) and touch sensing with a single driver (driving circuit) Can be reduced.

FIG. 4 is a plan view showing a cell-type organic electroluminescent device as a touch sensor according to embodiments of the present invention.

The display area of the cell-type organic electroluminescent device according to embodiments of the present invention includes a display pixel in which the pixel data line 611 and the connection part 612 between the touch electrodes connected to the gate driver are crossed And a touch electrode 622 may be formed on the display pixel so as to correspond to the display pixel.

In addition, the display area of the in-cell type organic electroluminescent device according to embodiments of the present invention includes the first to fourth surfaces, the gate driver 610 may be formed on the first surface, A data driver (e.g., a data driver & thouche readout) 620 may be formed on the second side perpendicular to the gate driver 610.

The gate driver 610 may also be referred to as a 'scan driver', and may sequentially drive a plurality of gate lines by sequentially supplying scan signals to a plurality of gate lines.

In addition, the gate driver 610 can sequentially supply scan signals of an On voltage or an Off voltage to a plurality of gate lines under the control of a timing controller (not shown).

When a specific gate line is opened by the gate driver 610, the data driver 620 can convert the image data received from the timing controller (not shown) into analog data voltages and supply the data voltages to a plurality of data lines.

Also, the data driver 620 can detect the row data for each touch node by supplying a driving signal to the gate line and using a read-out signal output from the lead-out line of the touch sensing circuit.

To use touch, it can be divided into touch sensing circuit and touch driving.

The touch sensing circuit of the cell-type organic electroluminescent device, which is a touch sensor according to embodiments of the present invention, may be driven by sharing a gate driver for driving a display pixel, or the touch sensing circuit may share a data driver for driving a display pixel .

Furthermore, the touch sensing circuit of the in-cell type organic electroluminescent device according to the embodiments of the present invention can share both the display pixel driving gate driver and the display pixel driving data driver.

Conventionally, in order to drive the touch electrode 622, a special connection state is required for driving the touch driving unit and the touch driving unit.

However, the organic electroluminescent device of the cell type of a touch sensor according to embodiments of the present invention includes a gate driver 610 and a data driver (e.g., data driver & a gate driver 620, a touch electrode 622 and a touch electrode interconnection unit (a touch electrode connection unit 612 connected to the gate driver, which connects the x axis and the y axis, respectively) And may have the same connection structure as the drivers provided for driving the display pixels.

Therefore, the organic electroluminescent device of the in-cell type according to the embodiments of the present invention can connect and drive the touch sensing circuit and the pixel circuit without distinguishing them.

Therefore, since the touch sensing circuit of the cell-type organic electroluminescent device according to the embodiments of the present invention is driven by sharing the gate driver for driving the display pixels or the data driver, the structure of the touch sensing circuit is further simplified, It is possible to drive the organic electroluminescent element of the in-cell type of the touch sensor in a simple driving mode and reduce the process cost for manufacturing the gate driver for a touch and the data driver.

5A is a circuit diagram illustrating a touch sensing circuit of a 2T1C included in a touch sensor of a cell type organic electroluminescent device according to embodiments of the present invention.

The touch sensing circuit has an active touch sensing circuit structure and can be driven by a gate driver corresponding to N and N + 1 and a wiring corresponding to the source voltage (VSS) and the output (Output).

In addition, the touch sensing circuit may have a 2T1C structure including a first touch sensing thin film transistor T ₁ , a second touch sensing thin film transistor T ₂ , and a capacitor C ₁ .

The first touch sensing thin film transistor Tl may be a touch driving thin film transistor (Driving TFT) for adjusting the touch sensing voltage and sensing the touch.

The first touch sensing thin film transistor T1 is turned on according to a gate pulse from the gate line N and N + 1, and the touch switch thin film transistor is turned on by a voltage (gate voltage) The current flowing to the touch sensor output processing section through the lead-out line can be adjusted.

The second touch sensing thin film transistor T2 can turn off the first touch sensing thin film transistor T1 and perform a reset function.

The gate electrode of the second touch sensing thin film transistor T2 is connected to the gate line N, N + 1 so that the second touch sensing thin film transistor T2 can share the gate line N, N + 1 with the OLED driving thin film transistor. N + 1).

The capacitor C ₁ may include an area capacitance due to the area of the touch electrode and a gap capacitance due to the thickness of the passivation layer.

Therefore, when no touch occurs in the organic electroluminescent device of the cell type of the touch sensor according to the embodiments of the present invention, since the areas of the touch electrodes are all the same and the thickness of the passivation layer is constant, Lt; / RTI >

However, in the case of touching a cell-type organic electroluminescent device, which is a touch sensor according to embodiments of the present invention, with a finger, a touch capacitor C _T is naturally generated, It is possible to know whether or not the touch is made because the change in the size of the charge storage capacity (C ₁ + C _T ) is caused and the touch operation is performed.

More specifically, when a touch is not generated in a cell-type organic electroluminescent device according to embodiments of the present invention, a touch sensing circuit formed in the entire display area may include a capacitor C ₁ having the same size, When the touch occurs, the touch capacitor C _T is added at the portion where the touch is generated, so that a change in the size of the total capacitance C ₁ + C _T occurs at the portion where the touch occurs, Can be detected.

FIG. 5B is a timing diagram illustrating a change in output voltage of a touch sensing circuit included in a cell-type organic electroluminescent device, which is a touch sensor according to embodiments of the present invention, according to a state of a touch / (timing diagram) graph.

Referring to FIG. 5B, the touch sensing circuit included in the in-cell type organic electroluminescent device according to the embodiments of the present invention has an output voltage of about 2 V at the time of touch, The output voltage is about 0 V, so that the touch state and the untouched state are distinctly distinguished, and it is possible to detect whether the touch state is high or not.

6 is a circuit diagram illustrating a 4T1C touch sensing circuit included in a touch sensor of a cell type organic electroluminescent device according to embodiments of the present invention.

The touch sensing circuit of 4T1C shown in Fig. 6 may have the same configuration as the touch sensing circuit of 2T1C shown in Fig. 5A.

The touch sensing circuit of a cell-type organic electroluminescent device according to embodiments of the present invention includes a first touch sensing thin film transistor, a second touch sensing thin film transistor, a third touch sensing thin film transistor, a fourth touch sensing thin film transistor, Transistors, and capacitors.

The touch sensing circuit of the 4T1C of the organic electroluminescent device of the cell type which is the touch sensor according to the embodiments of the present invention shares both the gate line and the data line (column line) .

Therefore, although the touch sensing circuit is complicated by including the 4T1C touch sensing circuit, the touch sensing circuit structure is not limited to the XY driving And the data line) are simultaneously used, the structure of the touch sensing circuit is further simplified, and it is possible to drive a touch sensor in-cell type organic electroluminescent device in a simple driving mode, and to manufacture a touch gate driver and a data driver It is possible to reduce the process cost.

In addition, the organic electroluminescent device of the in-cell type according to the embodiments of the present invention includes the 4T1C touch sensing circuit, so that both the gate driver and the touch sensing circuit can be incorporated.

7A and 7B are views illustrating an organic electroluminescent device of a-cell type, which is a touch sensor according to embodiments of the present invention, according to the size of the touch sensing circuit.

Referring to FIG. 7A, the black portion represents a touch sensing circuit of a -cell type organic electroluminescent device which is a touch sensor according to the embodiments of the present invention. The width of the touch sensing circuit may be 20 μm or less, The sensing circuit may have a vertical width of 260 mu m.

7A shows an example of applying a touch sensing circuit for a 40-inch UHD to a pixel. In the case of a pixel size of 230 x 230 μm ² , the touch electrode is ~ 2 x 2 mm ² , the touch sensing circuit is ~ 20 x 230 Mu m < ² &gt;, and the area occupied by the touch sensing circuit per pixel may be &lt; ~ 0.09%.

7B, the black portion represents a touch sensing circuit of a -cell type organic electroluminescent device which is a touch sensor according to embodiments of the present invention, the width of the touch sensing circuit may be 20 μm or less, The sensing circuit may have a vertical width of 138 mu m.

FIG. 7B shows an example of applying a touch sensing circuit for a 24-inch UHD to a pixel. The pixel size is 138 x 138 μm ² , The touch electrode may be ~ 2 x 2 mm ² , the touch sensing circuit may be ~ 20 x 138 m ² , and the area occupied by the touch sensing circuit per pixel may be < ~ 0.06%.

8 is an image showing a single touch sensing circuit included in a cell-type organic electroluminescent device, which is a touch sensor according to embodiments of the present invention.

Referring to FIG. 8, a single touch sensing circuit included in a touch sensor of a cell type organic EL device according to embodiments of the present invention includes two transistors and one capacitor.

9A to 9C are timing diagram graphs illustrating changes in output voltage of a touch sensing circuit included in a cell type organic electroluminescent device according to embodiments of the present invention, to be.

9A to 9C, the touch sensing circuit driving voltage (VDD) is 15 V, the frame rate is 5 kHz, and the touch voltage The size of the electrode is 500 탆 ² .

FIG. 9A shows a change in output voltage of a touch sensing circuit included in a cell-type organic electroluminescent device which is a touch sensor according to embodiments of the present invention in an untouched state, and FIG. Cell type organic electroluminescent device according to embodiments of the present invention in a touch state (slightly thouched), FIG. 9C shows a change in output voltage of the touch sensing circuit included in the strongly touch state Cell type organic electroluminescent device according to embodiments of the present invention in a full-throtched manner.

9A to 9C, the output voltage of the touch sensing circuit included in the cell-type organic electroluminescent device according to the embodiments of the present invention in an untouched state is 1.6V Depending on the touch sensitivity, it is changed to 280 mV in the slightly thouched state and to 0 V in the full touch state (full thouched state).

Therefore, it can be seen that the voltage state of the organic electroluminescent device of the in-cell type of the touch sensor according to the embodiments of the present invention changes according to the degree of touch.

FIGS. 10A to 10C are timing diagrams illustrating changes in output voltage of a touch sensing circuit included in a cell-type organic electroluminescent device, which is a touch sensor according to embodiments of the present invention, Graph.

FIGS. 10A to 10C show the fall time and the rising time of the sensed touch voltage when the touch is performed.

Referring to FIGS. 10A to 10C, the fall time T _fall is 1.5 ms and the rise time T _rise is 3.4 ms. In particular, referring to FIG. 10C, And the voltage in the untapped state is dynamically changed

11 is an image showing a touch sensing circuit and a scan driver of a cell-type organic electroluminescent device, which is a touch sensor according to embodiments of the present invention, 8X8.

In Fig. 11, if the row driver is a gate driver, the column driver may be a data driver, and if the row driver is a data driver, the column driver may be a gate driver.

Referring to FIG. 11, a row driver is formed on a side of a touch sensing circuit of a cell-type organic electroluminescent device, which is a touch sensor according to embodiments of the present invention, And a column driver is formed on a vertical plane.

The row driver and the column driver refer to a gate driver and a column gate driver for touch driving and a row driver and a column driver colum driver) can manufacture the touch panel by creating the same driving environment as the gate driver and the column gate driver for driving the pixels of the AMOLED.

FIG. 12 is a timing diagram showing a voltage change of a touch sensing circuit of a cell-type organic electroluminescent device which is a touch sensor according to embodiments of the present invention of 8 × 8 according to a touched point.

12, when a raw driver and a column driver are referred to as a gate driver and a column gate driver for touch driving, respectively, a touch panel, The properties were measured.

In addition, FIG. 12 shows that a touched position is sensed within one column of touch electrodes during a time corresponding to one frame (one frame).

Referring to FIG. 12, it can be seen that the non-touch state is 700 mV, and the touch state is 10 V, and the voltage difference is considerably large.

Figure 13 shows the result of voltage being sensed per touch electrode.

FIG. 13 is a graph showing a voltage difference of a touch sensing circuit of a cell-type organic electroluminescent device, which is a touch sensor according to embodiments of the present invention of 8X8 in a touch / untouched state.

FIG. 13 shows a touch voltage output sensed according to coordinates (x, y) of the corresponding touch electrode in FIG. 12, and shows a mapping result showing a touch sensing output composed of 8x8.

Referring to FIG. 13, it can be seen that the magnitude of the output voltage (different color) varies depending on the portion to be touched.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. This is possible.

Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the equivalents of the claims, as well as the claims.

H1: first contact hole H2: second contact hole
101, 201, and 301: OLED driving thin film transistor
102, 202, 302: Touch sensing thin film transistor
110, 210, 310: substrate 120, 220, 320: gate electrode
130, 230, 330: gate insulating film 140, 240, 340: semiconductor layer
151, 251, 351: source electrodes 152, 252, 352: drain electrodes
161, 261, 361: a first passivation layer
162, 262, 362: a second passivation layer (planarization layer)
163, 263, and 363: a third passivation layer (bank)
164, 264, 364: Fourth passivation layer 171, 271, 371: OLED anode
172, 272, 273: organic light emitting devices 173, 273, 373: OLED cathode
180, 280, 380: touch electrode 401: emission region
402: touch electrode area 510: display pixel
511: pixel data line 512: gate line
520: touch sensing circuit 521: touch sensor data line
522: touch electrode 610: gate driver
611: pixel data line 620: data driver
612: connection portion between the gate driver and the touch electrode
621: connection between the data driver and the touch electrodes connected thereto

Claims (7)

At least one display pixel including an organic light emitting diode and at least one OLED driving thin film transistor; And
At least one touch sensing circuit including at least one touch sensing thin film transistor connected to the touch electrode,
Lt; / RTI &gt;
Wherein the at least one touch sensing circuit is formed on a side portion of the at least one display pixel.
The method according to claim 1,
Wherein the at least one OLED driving thin film transistor and the at least one touch sensing thin film transistor share a gate line.
The method according to claim 1,
Wherein the touch sensing circuit comprises a first touch sensing thin film transistor, a second touch sensing thin film transistor, and a capacitor.
The method according to claim 1,
Wherein the touch sensing circuit includes a first touch sensing thin film transistor, a second touch sensing thin film transistor, a third touch sensing thin film transistor, a fourth touch sensing thin film transistor, and a capacitor. Light emitting element.
The method according to claim 1,
Wherein the touch sensing circuit is driven by sharing a gate driver for driving a display pixel.
The method according to claim 1,
Wherein the touch sensing circuit is driven by sharing a data driver for driving a display pixel.
A display device comprising a cell-type organic electroluminescent device, which is a touch sensor according to any one of claims 1 to 6.

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