KR101390400B1 - Display and method of manufacturing the same - Google Patents

Abstract

The present invention relates to a display device with a built-in touch panel function.

In the display device of the present invention, a second substrate and a first substrate facing each other, a driving thin film transistor formed on the first substrate, a source electrode and a drain electrode are formed on the first substrate, and a gate is formed on the second substrate. And a thin film transistor for detecting a touch position on which an electrode is formed.

According to the present invention, it is possible to solve the problem of the conventional resistance method in which the resistance is increased by the alignment layer, the touch sensitivity is lowered, and the sensitivity difference for each position is generated.

Touch Panel, Top Gate, TFT, Conductive Spacer, Touch Position Detection

Description

DISPLAY DEVICE AND MANUFACTURING METHOD THEREOF

The present invention relates to a display device, and more particularly, to a display device with a built-in touch panel function capable of improving touch sensitivity and a method of manufacturing the same.

A touch panel is a device that can detect a location of a human hand or an object by touching a character or a specific location displayed on a screen by a display device without using a keyboard, and can perform a specific process. Since the conventional touch panel is manufactured separately from the display device and bonded to the display device, the thickness of the display device is increased. Therefore, in order to not increase the thickness, a touch panel embedded display device having a built-in touch panel function in manufacturing a display device has been proposed.

The touch panel embedded display device may be classified into a capacitive method and a resistive method. The capacitive method is a method in which a liquid crystal cell is pressurized to sense a signal when the capacitance is changed, and the resistance method is a method of identifying a position where the resistance is changed by pressing. However, the capacitive method is a method in which writing is impossible, and the resistive method is a method in which writing is possible.

In the resistive touch panel embedded display device, a sensing electrode is formed on a lower substrate on which a thin film transistor and a pixel electrode are formed, and a conductive spacer is formed on an upper substrate on which a color filter and a common electrode are formed. Determine where the sensing electrode contacts. However, in the display device, an alignment layer, which is an insulator, is formed on a surface where the lower substrate and the upper substrate face each other, thereby increasing the resistance between the conductive column spacer of the upper substrate and the sensing electrode of the lower substrate, thereby lowering the sensitivity and causing a difference in sensitivity for each position. There is a problem that occurs.

The present invention provides a display device capable of preventing a drop in touch sensitivity even after the alignment film is formed.

The present invention provides a display device in which a source electrode and a drain electrode for position detection are formed on a lower substrate, and the conductive spacer of the upper substrate serves as a gate electrode so that a channel is generated between the source electrode and the drain electrode by the conductive spacer. do.

The present invention provides a display device in which a source electrode for position detection of a lower substrate is supplied with power from a gate line or a data line, and the drain electrode for position detection is connected to a sensing line.

A display device according to an aspect of the present invention includes a second substrate and a first substrate facing each other; A driving thin film transistor formed on the first substrate; And a thin film transistor for detecting touch position, wherein a source electrode and a drain electrode are formed on the first substrate, and a gate electrode is formed on the second substrate.

The first substrate may include a gate line formed in one direction of the first substrate; A first sensing line spaced apart from the gate line and formed in the same direction; A data line insulated from and intersecting the gate line; And a second sensing line spaced apart from the data line and formed in the same direction.

The second sensing line is formed for at least one unit pixel.

The touch position detecting thin film transistor includes at least two thin film transistors having the gate electrode and the source electrode in common and having at least two drain electrodes.

The source electrode is connected to the gate line, and the drain electrode is connected to the first and second sensing lines, respectively.

The display device may further include first and second sensing electrodes formed to be spaced apart from each other in an area where the first and second sensing lines cross each other.

The source electrode extends from the first sensing electrode, and the drain electrode extends from the second sensing line and the second sensing electrode, respectively.

A first connection electrode for connecting the first sensing electrode and the gate line; And a second connection electrode for connecting the second sensing electrode and the first sensing line.

The source electrode is formed to be bent.

The source electrode is connected to the data line, and the drain electrode is connected to the first and second sensing lines, respectively.

The apparatus further includes a power supply line for supplying power to the source electrode.

The source electrode is connected to the power line, and the drain electrode is connected to the first and second sensing lines, respectively.

The gate electrode is a conductive spacer.

The conductive spacer is formed at a position corresponding to the source electrode and the drain electrode.

In accordance with another aspect of the present invention, a display device includes: a first substrate and a second substrate facing each other; A gate line and a first sensing line extending in one direction on the first substrate and spaced apart from each other; A data line and a second sensing line extending in another direction crossing the gate line and spaced apart from each other; A pixel electrode formed at an intersection of the gate line and the data line; A driving thin film transistor connected to the gate line, the data line, and the pixel electrode; And a thin film transistor for touch position detection connected to the power line and the first and second sensing lines and driven by the conductive spacer of the second substrate.

The power line includes the gate line or the data line.

The thin film transistor for detecting touch position may include a first thin film transistor including a source electrode connected to the power line, a drain electrode connected to the first sensing line, and the conductive spacer serving as a gate electrode; And a second thin film transistor including a source electrode connected to the power line, a drain electrode connected to a second sensing line, and the conductive spacer serving as the gate electrode.

According to the present invention, a position detecting source electrode and a drain electrode are formed on a lower substrate, and the conductive spacer of the upper substrate serves as a gate electrode to form a position detecting thin film transistor. In addition, the position detection source electrode is connected to a gate line or a data line of the lower substrate to receive power, and the position detection drain electrode is connected to the first and second sensing lines. In such a configuration, when the conductive spacer of the upper substrate touches the position detection source electrode and the drain electrode by the touch operation, a channel is formed between the position detection source electrode and the drain electrode by the conductive spacer, and the source electrode is drained from the source electrode to the drain electrode. Current will flow. As a result, the touch position is detected.

Therefore, it is possible to solve the problem of the conventional resistance method in which the resistance is increased by the alignment layer, the touch sensitivity is decreased, and the sensitivity difference for each position is generated. That is, the touch sensitivity is not lowered even by the alignment layer, and the positional sensitivity difference does not occur.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be understood, however, that the invention is not limited to the disclosed embodiments, but is capable of other various forms of implementation, and that these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concept of invention to those skilled in the art. It is provided to let you know completely. In the drawings, the thickness is enlarged to clearly illustrate the various layers and regions, and the same reference numerals denote the same elements in the drawings. Also, where a section such as a layer, film, region, plate, or the like is referred to as being "on top" or "on" another section, not only when each section is "directly above" And includes another portion between the other portions.

1 is a schematic block diagram of a touch panel embedded display device according to an exemplary embodiment.

Referring to FIG. 1, a display device according to an exemplary embodiment includes a display panel 100, a panel driver 400, a touch position detector 500, and a position determiner 600.

The display panel 100 includes a lower substrate 200 on which a driving thin film transistor, a pixel electrode, a sensing line, a position detection source electrode, and a drain electrode are formed, and an upper substrate 300 on which a color filter, a common electrode, a conductive spacer, and the like are formed. ) And a liquid crystal layer (not shown) formed between the lower substrate 200 and the lower substrate 300. In the present specification, the upper substrate 300 and the lower substrate 200 may be represented by the second substrate and the first substrate, respectively, or may be represented by the first substrate and the second substrate, respectively.

A plurality of gate lines GL1 to GLn extending in one direction and a plurality of data lines DL1 to DLm extending in the other direction are formed on the lower substrate 200. [ Pixels are formed in each region where a plurality of gate lines GL1 to GLn cross a plurality of data lines DL1 to DLm. In addition, the driving thin film transistor T1 and the pixel electrode 280, which are switching elements, are formed in the pixels, respectively. The driving thin film transistor T1 includes a gate electrode, a source electrode, and a drain electrode, so that the gate electrode is connected to the gate line GL, the source electrode is connected to the data line DL, and the drain electrode is the pixel electrode 280. ) In addition, a plurality of first sensing lines (not shown) and a plurality of second sensing lines (not shown) are formed on the lower substrate 200 to perform a touch panel function. The first sensing line may extend in the same direction as the gate line GL, and the second sensing line may extend in the same direction as the data line DL and electrically insulate and cross each other. Here, the first and second sensing lines are connected to the touch position detector 500. The first and second sensing lines may be formed for each unit pixel including, for example, red (R), green (G), and blue (B) subpixels, and may be formed for each subpixel or at predetermined intervals. have. Also, a position detection source electrode (not shown) connected to the gate line GL or the data line DL and a position detection drain electrode (not shown) connected to the first and second sensing lines are formed. The position detecting source electrode and the drain electrode may be formed for each unit pixel, for example, for each blue (B) subpixel. In addition, an alignment layer (not shown) may be formed on the lower substrate 200 to adjust the alignment of the liquid crystal.

The upper substrate 300 includes a color filter, a common electrode, and the like. The upper substrate 300 is opposed to the lower substrate 200 and is coupled to the lower substrate 200 to receive a liquid crystal layer (not shown). The upper substrate 300 may be formed of a color filter substrate on which color filters corresponding to respective pixels are formed. However, the color filter may be formed on the lower substrate 200. [ In addition, a plurality of conductive spacers (not shown) are formed on the upper substrate 300 to perform a touch panel function. The conductive spacer may be formed per unit pixel and may be formed for each sub pixel. In addition, an alignment layer (not shown) may be formed on the upper substrate 300 to adjust the alignment of the liquid crystal.

Here, the conductive spacer of the upper substrate 300 serves as a position detection gate electrode. Therefore, the conductive spacer of the upper substrate 300 and the source electrode and the drain electrode for position detection of the lower substrate form a thin film transistor for position detection. In this state, when the conductive spacer contacts the position detection source electrode and the drain electrode of the lower substrate 200, a channel is generated between the position detection source electrode and the drain electrode by the conductive spacer, and the position detection is performed from the position detection source electrode. Current flows to the drain electrode. At this time, since the position detection drain electrode is connected to the first and second sensing lines, the position detection thin film transistor detects the turned-on position.

The panel driver 400 includes a timing controller 410, a power supply unit 420, a gradation voltage generator 430, a data driver 440, and a gate driver 450.

The timing controller 410 controls the overall operation of the display device. The timing controller 410 displays an image on the display panel 100 as the R, G, and B raw data signals DATA_O and the first control signal CNTL1 are provided from a host system such as a graphic controller (not shown). The first data signal DATA1, the second control signal CNTL2, the third control signal CNTL3, and the fourth control signal CNTL4 are outputted. Specifically, the first control signal CNTL1 includes a main clock signal MCLK, a horizontal synchronization signal HSYNC, and a vertical synchronization signal VSYNC. The second control signal CNTL2 includes a horizontal start signal STH, an inverted signal REV and a data load signal TP for controlling the data driver 420. The third control signal CNTL3 includes a start signal STV, a clock signal CK, an output enable signal OE, and the like that control the gate driver 430. The fourth control signal CNTL4 includes a clock signal CLK and an inverted signal REV for controlling the power supply 450. Also, the timing controller 410 provides the data driver 440 with the first data signal DATA1 of R ', G', and B 'whose output timings of the primitive data signal DATA_O are controlled.

The power supply unit 420 may perform lower voltages to perform the common voltages Vcom and Vcst and the touch screen function provided to the display panel 100 in response to the fourth control signal CNTL4 output from the timing controller 410. The initial driving voltage Vid provided to the 200, the analog driving voltage AVDD provided to the gray voltage generator 430, and the gate on voltage Von and gate off voltage Voff provided to the gate driver 450. )

The gradation voltage generator 430 generates a gradation voltage by using a plurality of gradation levels corresponding to the number of gradation levels based on a distribution resistance having a resistance ratio to which a gamma curve is applied using the analog driving voltage AVDD provided from the power supply unit 420 as a reference voltage, And outputs the gradation voltage VGMA_R.

The data driver 440 generates the gradation voltage VGMA based on the reference gradation voltage VGMA_R output from the gradation voltage generator 430. [ In addition, the data driver 440 may receive a digital data first data signal DATA1 provided in line units based on the second control signal CNTL2 and the gray voltage VGMA input from the timing controller 410. The output timing of the data signal is controlled and output to the data lines DL1 through DLm.

The gate driver 450 generates a gate signal according to the third control signal CNTL3 output from the timing controller 410 and the gate on / off voltage Von.Voff output from the power supply unit 420, (GL1 to GLn).

The touch position detector 500 detects the position coordinates of the point where the external pressure is applied and outputs the first detection signal DS1 and the second detection signal DS2. That is, the position where the position detection thin film transistor is turned on is detected.

The positioning unit 600 combines the position coordinates of each of the x and y axes determined by the first and second detection signals DS1 and DS2 output from the touch position detector 500 to display an external pressure display panel ( The position applied to 100 is determined.

2 is a schematic plan view of a display panel with a built-in touch panel function according to an exemplary embodiment of the present invention, and FIGS. 3, 4, and 5 are lines II ′, II-II ′, and III- of FIG. 2. It is sectional drawing of the state cut along the III 'line. The case where the conductive spacer, the position detecting source electrode and the drain electrode of the present embodiment are formed for each unit pixel composed of three subpixels will be described as an example. In addition, the unit pixel includes a red (R) subpixel, a green (G) subpixel, and a blue (B) subpixel, and a conductive spacer, a source electrode for position detection, and a drain electrode are disposed in the pixel region of the blue (B) subpixel. The case where it is formed is demonstrated.

2, 3, 4, and 5, in an exemplary embodiment, the touch panel embedded display panel 100 may include a lower substrate 200, an upper substrate 300, and a lower substrate 200 disposed to face each other. It includes a liquid crystal layer (not shown) formed between the substrate 200 and the upper substrate 300.

The lower substrate 200 includes a plurality of gate lines 220 extending in one direction on the first insulating substrate 210, a plurality of data lines 260 extending to cross the gate lines 220, and a gate. The panel driving thin film connected to the pixel electrode 280 formed in the sub pixel area defined by the line 220 and the data line 260, and the gate line 220, the data line 260, and the pixel electrode 280. And a transistor (hereinafter referred to as "first thin film transistor") T1. Here, the first thin film transistor T1 is formed for each sub pixel, and a bottom gate type in which the first gate electrode 222 is formed under the first source electrode 261 and the first drain electrode 262. type) thin film transistor. The apparatus further includes a first sensing line SL1 spaced apart from the gate line 220 and extending in one direction, and a second sensing line SL2 spaced apart from the data line 260 and extended in the other direction. In addition, the first and second sensing electrodes 263 and 264 formed spaced apart from each other in one sub pixel area for each unit pixel, the second source electrode 265 branched from the first sensing electrode 263, and the second sensing line ( And a second drain electrode 266 branched from SL2 and a third drain electrode 267 branched from second sensing electrode 264. The first connection electrode 281 connecting the gate line 220 and the first sensing electrode 263, and the second connection electrode 282 connecting the first sensing line SL1 and the second sensing electrode 264. More).

For example, the gate line 220 extends in the horizontal direction, and a portion of the gate line 220 protrudes to form the gate electrode 222. In addition, the first sensing line SL1 is formed to be spaced apart from the gate line 220 by a predetermined distance in the same direction as the gate line 220. In addition, a storage electrode line (not shown) may be formed to be spaced apart from the gate line 220 and the first sensing line SL1, respectively. The gate line 220, the first sensing line SL1, and the storage electrode line (not shown) are formed on the same layer, and may be formed in the same process.

The gate insulating layer 230 is formed on the entire surface including the gate line 220. The gate insulating layer 230 may be formed as a single layer or a multilayer using silicon oxide (SiO ₂ ), silicon nitride (SiN x), or the like.

A first active layer 241 made of a semiconductor such as amorphous silicon is formed on the gate insulating layer 230 on the gate electrode 222, and silicide or n-type impurities are heavily doped on the first active layer 241. A first ohmic contact layer 251 made of a semiconductor material such as n + hydrogenated amorphous silicon is formed. The first ohmic contact layer 251 may be removed in the first channel portion between the first source electrode 261 and the first drain electrode 262, respectively. In addition, a second active layer 242 is formed in a predetermined region above the gate insulating layer 230 in one subpixel of the unit pixel, for example, a blue (B) subpixel region, and a second portion above the second active layer 242. The ohmic contact layer 252 is formed. The second active layer 242 is formed by the same process as the first active layer 242, and the second ohmic contact layer 252 is formed by the same process as the first ohmic contact layer 251. In addition, the second ohmic contact layer 252 may include a second channel portion between the second source electrode 265 and the second drain electrode 266, the second source electrode 265, and the third drain electrode 266 and 267. It can be removed in the third channel section in between.

The data line 260 extends in a direction crossing the gate line 220 and the first sensing line SL1, that is, in a vertical direction, and is formed on the gate insulating layer 230. An area where the data line 260 crosses the gate line 220 is defined as a subpixel area. The first source electrode 261 is formed by protruding from the data line 260 to an upper portion of the first ohmic contact layer 251, and is spaced apart from the first source electrode 261 and is disposed on the first ohmic contact layer 251. The first drain electrode 262 is formed. In addition, the second sensing line SL2 is formed to be spaced apart from the data line 260 in the same direction as the data line 260. One second sensing line SL2 is formed for each unit pixel, for example, to pass through the blue (B) subpixel region.

When the data electrode 260 and the second sensing line SL2 are formed, the first and second sensing electrodes 263 and 264 are spaced apart from each other in the blue (B) subpixel area. In addition, a second source electrode (hereinafter referred to as a “second source electrode”) 265 for detecting a touch position is formed by branching from the first sensing electrode 263, and branching from the second sensing line SL2 to touch. A second drain electrode (hereinafter referred to as a "second drain electrode") 266 for position detection is formed, and branches from the second sensing electrode 264 to form a third drain electrode (hereinafter, referred to as "third"). 267) is formed. The second source electrode 265 is formed to have a predetermined curvature, for example, a portion extending to the right and a portion extending downward, a portion extending to the left and a portion extending downward, and a portion extending to the right again. It is formed to have a predetermined bend. In addition, the second source electrode 265 has a work space open to the left by a portion extending to the right, a portion extending to the left, and a portion extending downward, and a portion extending to the left and a portion extending to the right. And the other space opened to the right by the part extended downward is formed. Thus, one space and the other space is preferably formed at least one each. The second drain electrode 266 is formed to be spaced apart from the second source electrode 265 in a space opened to the left of the second source electrode 265, and the third drain electrode 267 is formed as the second source electrode ( It is formed to be spaced apart from the second source electrode 265 on the other space opened to the right of the 265. A second channel portion is formed by the second active layer 242 in the region between the second source electrode 265 and the second drain electrode 266, and between the second source electrode 265 and the third drain electrode 267. The third channel portion is formed by the second active layer 242 in the region of.

The passivation layer 270 is formed on the entire surface including the gate line 220 and the data line 260. The protective film 270 may be formed of an inorganic insulating film, an organic insulating film, or the like, and has a thickness of about 1000 GPa. In addition, a predetermined region of the passivation layer 270 is removed to form a plurality of contact holes. That is, a part of the first contact hole 271 exposing a part of the first drain electrode 262 and the part of the second contact hole 272 and the gate line 220 exposing a part of the first sensing electrode 263 are formed. The third contact hole 273 exposing the portion, the fourth contact hole 274 exposing a portion of the second sensing electrode 264 and the fifth contact hole 275 exposing a portion of the first sensing line SL1 are provided. Is formed. The third contact hole 273 and the fifth contact hole 275 are formed by removing the gate insulating film 230 to expose the gate line 220 and the first sensing line SL1.

The pixel electrode 280 is formed on the passivation layer 270. The pixel electrode 280 is formed of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). The pixel electrode 280 is connected to the first drain electrode 262 through the first contact hole 271. In addition, when the pixel electrode 280 is formed, the first connection electrode 281 and the second connection electrode 282 are formed to be spaced apart from the pixel electrode 280. The first connection electrode 281 is formed to connect the first sensing electrode 263 and the gate line 220 through the second and third contact holes 272 and 273. The second sensing electrode 282 is formed to connect the second sensing electrode 264 and the first sensing line SL1 through the fourth and fifth contact holes 274 and 275.

Meanwhile, a first alignment layer 290 for controlling the alignment of the liquid crystal is formed on the entire top including the pixel electrode 280, the first connection electrode 281, and the second connection electrode 282. The first alignment layer 290 is formed to a thickness of about 1000 GPa, and is formed using polyimide.

In addition, the upper substrate 300 includes a black matrix 320 formed on the second insulating substrate 310, a color filter 330, and a common electrode 340. In addition, a conductive spacer 350 is further included.

The black matrix 320 is in a region other than the subpixel, for example, the gate line 221, the data line 260, the first thin film transistor T1, the first and second sensing lines SL1 of the lower substrate 200. And an upper substrate 300 corresponding to SL2, the first and second sensing electrodes 263 and 264, and the second source electrode 265, the second and third drain electrodes 266 and 267. . The black matrix 320 prevents light leakage to areas other than the sub pixel area and optical interference between adjacent sub pixel areas. Further, the black matrix 320 is made of a photosensitive organic material to which a black pigment is added. As black pigment, carbon black, titanium oxide, etc. are used.

The color filter 330 is formed by repeating the red (R), green (G), and blue (B) filters around the black matrix 320. The color filter 330 has a function of irradiating light from a light source and imparting hue to light passing through a liquid crystal layer (not shown), and may be formed of a photosensitive organic material.

One conductive spacer 350 is formed for each unit pixel. For example, a region formed on the blue color filter 330 in the blue subpixel, and including a portion of the second source electrode 265, the second and third drain electrodes 266 and 267 of the lower substrate 200. It is formed in the area corresponding to. In this case, a black matrix 320 is formed under the blue color filter 330 on which the conductive spacer 350 is formed. However, the second source electrode 265 is formed on the upper portion partially overlapping the second active layer 242, and the second and third drain electrodes 266 and 267 are formed to partially overlap the second active layer 242. . Therefore, the conductive spacer 350 is formed in one region of the upper substrate 300 corresponding to the second active layer 242 of the lower substrate 200. In addition, the conductive spacer 350 may be formed in, for example, a rectangular shape to correspond to the shape of the second active layer 242. In addition, the conductive spacer 350 may be formed in various shapes in a region corresponding to the second active layer 242. On the other hand, the conductive spacer 350 is formed by forming the columnar spacer 350a of an insulating material after the color filter 330 is formed and then forming the common electrode 340 on the spacer 350a. In addition, the conductive spacer 350 may be formed by stacking and patterning a plurality of color filters 330 and forming a plurality of common electrodes 340 on the stacked color filters 330.

The common electrode 340 is formed of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO), and is formed on the insulating substrate 310 including the black matrix 320 and the color filter 330. .

Meanwhile, a second alignment layer 360 may be formed on the common electrode 340 to control the alignment of the liquid crystal. The second alignment layer 360 is formed to have a thickness of about 1000 GPa using polyimide.

The touch panel embedded display panel 100 according to the exemplary embodiment of the present invention configured as described above includes a second thin film transistor (hereinafter, referred to as a "second thin film transistor") T2 and a position detection for each pixel. A third thin film transistor (hereinafter referred to as "third thin film transistor") T3 is formed to detect the touch position. The second thin film transistor T2 includes a second source electrode 265 and a second drain electrode 266 formed on the lower substrate 200, and the third thin film transistor T3 is disposed on the lower substrate 200. The formed second source electrode 265 and the third drain electrode 267 are included. That is, the second and third thin film transistors T2 and T3 including the second source electrode 265 as the common source electrode and the second and third drain electrodes 266 and 267 are formed. Here, the conductive spacer 350 formed on the upper substrate 300 serves as a gate electrode of the second and third thin film transistors T2 and T3. Accordingly, the second and third thin film transistors T2 and T3 are formed of a top gate type thin film transistor having a gate electrode formed on the source electrode and the drain electrode.

The second and third thin film transistors T2 and T3 may include the second source electrode 265 and the second and third drain electrodes 266 and 267 when the gate electrode, that is, the conductive spacer 350 is in the normal position. There is no electric field formed between them. However, when the upper substrate 300 and the lower substrate 200 contact by the touch operation, an electric field is applied to the lower substrate 200 by the conductive spacer 350, and thus the second source electrode 265 and the second source electrode 265. A channel is formed between the second and third drain electrodes 266 and 267. In this case, a passivation layer 270, a first alignment layer 290, and a second alignment layer 360 exist between the conductive spacer 350, the second source electrode 265, and the second and third drain electrodes 266 and 267. As a gate insulating film, but the total thickness thereof is about 3000Å, there is no problem in forming the channel. For example, since the first thin film transistor formed in the sub pixel region generates an electric field with a gate insulating film 230 of about 4000 kV interposed therebetween, the thickness of about 3000 kW is sufficient to generate an electric field.

Accordingly, the current supplied from the gate line 220 is supplied to the second sensing line SL2 through the second source electrode 265 and the second drain electrode 266, and the second source electrode 265 and the third source. The drain electrode 267 is supplied to the first sensing line SL1. Accordingly, the touch position detector 500 shown in FIG. 1 connected to the first sensing line SL1 and the second sensing line SL2 detects a position to which pressure is applied, outputs a detection signal, and positions the detection signal. Input from the unit 600 to detect the touch position. In this case, a common voltage of about 0 to 15 V may be applied to the common electrode 340 of the upper substrate 300, and a common voltage of about 13 to 14 V may be applied to the second source electrode 265 of the lower substrate 200. The gate off voltage may be applied to generate a voltage difference. For example, a common voltage of about 6.5 V is applied to the common electrode 340 of the upper substrate 300, and about −7.5 V is applied to the second source electrode 265 connected to the gate line 220 of the lower substrate 200. A gate off voltage of may be applied. Therefore, a voltage difference of about 14 V occurs between the conductive spacer 350 and the second source electrode 265, so that the conductive spacer 350 can sufficiently function as a gate electrode.

Meanwhile, in the above embodiment, the second source electrode 265 is described as being connected through the gate line 220 and the first sensing electrode 263, but the second source electrode 263 is connected to the data line 260. It may be. In this case, the second source electrode 263 may be formed to branch from the data line 260. In addition, a power line separate from the gate line 220 or the data line 260 may be formed, and the second source electrode 263 may be connected to the power line.

In addition, the number of bends of the second source electrode 265 is increased to increase the width of the second and third channel portions between the second source electrode 265 and the second and third drain electrodes 266 and 267. A plurality of second and third drain electrodes 266 and 267 can be formed. That is, as illustrated in FIG. 6, the second source electrode 265 includes a plurality of portions extending to the right and a portion extending downward, a portion extending to the left and a portion extending downward, and a portion extending to the right again. It is formed repeatedly to have a predetermined curvature repeatedly. Accordingly, two or more work spaces opened to the left by a portion extending to the right, a portion extending to the left, and a portion extending downward to the left of the second source electrode 265 are formed, and a portion extending to the left and extending to the right are formed. Two or more other spaces opened to the right are formed by the divided portion and the portion extending downward. The second drain electrode 266 is formed to be spaced apart from the second source electrode 265 on two or more spaces branched from the second sensing line SL2 and opened to the left side of the second source electrode 265. The third drain electrode 267 is formed to be spaced apart from the second source electrode 265 on the other space branched from the second sensing electrode 264 and opened to the right side of the second source electrode 265. However, when the second source electrode 265 is formed in such a way as to form one space and another space as much as possible, the amount of current flowing through the second and third drain electrodes 266 and 267 increases, so that the sensing sensitivity is improved. Although it can make it possible, an aperture ratio can be reduced. Therefore, it is preferable to form the second source electrode 265 to have as many bends as possible without lowering the aperture ratio.

The display device for detecting a sensing position using transistors formed on the upper substrate and the lower substrate may be used for various display devices in addition to the LCD.

1 is a schematic block diagram of a touch panel embedded display device according to an exemplary embodiment.

2 is a plan view illustrating a touch panel built-in display panel according to an exemplary embodiment.

3 is a cross-sectional view taken along line I-I 'of FIG. 2;

4 is a cross-sectional view taken along the line II-II ′ of FIG. 2.

5 is a cross-sectional view taken along the line III-III ′ of FIG. 2.

6 is a top plan view of a touch panel built-in display panel according to another exemplary embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

100: display panel 200: lower substrate

300: upper substrate 400: panel driver

500: touch position detection unit 600: position determination unit

SL1: first sensing line SL2: second sensing line

263: first sensing electrode 264: second sensing electrode

265: second source electrode 266: second drain electrode

267: third drain electrode 350: conductive spacer

Claims (18)

A second substrate and a first substrate facing each other; A pixel driving thin film transistor formed on the first substrate; And And a thin film transistor for touch position detection, wherein a source electrode and a drain electrode are formed on the first substrate, and a gate electrode is formed on the second substrate. The method of claim 1, wherein the first substrate, A gate line formed in one direction of the first substrate; A first sensing line spaced apart from the gate line and formed in the same direction; A data line insulated from and intersecting the gate line; And a second sensing line spaced apart from the data line in the same direction. The display device of claim 2, wherein the second sensing line is formed for at least one unit pixel. The display device of claim 2, wherein the touch position detection thin film transistor includes at least two thin film transistors having the gate electrode and the source electrode in common and having at least two drain electrodes. The display device of claim 4, wherein the source electrode is connected to the gate line, and the drain electrode is connected to the first and second sensing lines, respectively. The display device of claim 5, further comprising: first and second sensing electrodes spaced apart from each other in a region where the first and second sensing lines cross each other. The display device of claim 6, wherein the source electrode extends from the first sensing electrode, and the drain electrode extends from the second sensing line and the second sensing electrode, respectively. The display device of claim 7, further comprising: a first connection electrode for connecting the first sensing electrode and the gate line; And And a second connection electrode for connecting the second sensing electrode and the first sensing line. The display device of claim 7, wherein the source electrode is curved. The display device of claim 4, wherein the source electrode is connected to the data line, and the drain electrode is connected to the first and second sensing lines, respectively. The display device of claim 2, further comprising a power line for supplying power to the source electrode. The display device of claim 11, wherein the source electrode is connected to the power line, and the drain electrode is connected to the first and second sensing lines, respectively. The display device of claim 1, wherein the gate electrode is a conductive spacer. The display device of claim 13, wherein the voltage applied to the conductive spacer is a common voltage of 0 to 15V. The display device of claim 13, wherein the conductive spacer is formed at a position corresponding to the source electrode and the drain electrode. A first substrate and a second substrate facing each other; A gate line and a first sensing line extending in one direction on the first substrate and spaced apart from each other; A data line and a second sensing line extending in another direction crossing the gate line and spaced apart from each other; A pixel electrode formed near the gate line and the data line; A pixel driving thin film transistor connected to the gate line, the data line and the pixel electrode; And a thin film transistor for touch position detection connected to a power line and first and second sensing lines and driven by a conductive spacer of the second substrate. The display device of claim 16, wherein the power line includes the gate line or a data line. The thin film transistor of claim 17, wherein the touch position detecting thin film transistor comprises: a first thin film transistor including a source electrode connected to the power line, a drain electrode connected to the first sensing line, and the conductive spacer serving as a gate electrode; And And a second thin film transistor including a source electrode connected to the power line, a drain electrode connected to a second sensing line, and the conductive spacer serving as the gate electrode.

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