Patent Publication Number: US-2023146494-A1

Title: Flexible display device including touch sensor

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a Continuation of U.S. patent application Ser. No. 17/850,938, filed on Jun. 27, 2022, which is a Division of U.S. patent application Ser. No. 16/816,740, filed Mar. 12, 2020, now issued as U.S. Pat. No. 11,372,450, which is a Division of U.S. patent application Ser. No. 15/647,267, filed Jul. 12, 2017, now issued as U.S. Pat. No. 10,671,122, which is a continuation of U.S. patent application Ser. No. 14/482,879, filed on Sep. 10, 2014, now issued as U.S. Pat. No. 9,720,449, which claims priority to and the benefit of Korean Patent Application No. 10-2013-0148436 filed in the Korean Intellectual Property Office on Dec. 2, 2013, the entire contents of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     1. Field 
     The described technology generally relates to a flexible display device including a touch sensor. 
     2. Description of the Related Technology 
     Display devices, such as liquid crystal displays (LCDs), organic light-emitting diode (OLED) displays, and electrophoretic displays (EPDs), include a field generating electrode and an electro-optical active layer. For example, OLED displays include an organic emission layer which functions as the electro-optical active layer. The field generating electrode is connected to a switching element, such as a thin film transistor (TFT), to receive a data signal. The electro-optical active layer displays an image by converting the data signal to an optical signal. 
     When a heavy and fragile glass substrate is used in a display panel of the display device, there is a limit to the portability and screen size thereof. Recently, flexible display devices using light plastic substrates as the substrate of a display panel have been developed since these substrates can be light, strong, and flexible. 
     SUMMARY OF CERTAIN INVENTIVE ASPECTS 
     One inventive aspect is a simplified manufacturing process of a flexible display device including a touch sensor which can reduce the associated costs. 
     Another aspect is a flexible display device including a touch sensor having a decreased thickness and improved optical characteristics, and reduced defects in the touch sensor, and improved durability when the flexible display device is bent so as to prevent impurities, such as moisture, from permeating into the touch sensor. 
     Another aspect is a display device including a flexible substrate, an emission member positioned on the flexible substrate, an encapsulation layer positioned on the emission member and including a plurality of encapsulating thin films, and a touch detecting layer included inside the encapsulation layer and including a touch sensor, in which the encapsulating thin films include at least one inorganic film and at least one organic film, and the touch detecting layer is positioned between the inorganic film and the organic film which are adjacent to each other. 
     Another aspect is a display device including a flexible substrate including a first film, an emission member positioned on the flexible substrate, an encapsulation layer positioned on the emission member, and a touch detecting layer formed on an upper surface or a lower surface of the first film and including a touch sensor. 
     At least one first encapsulating thin film positioned on the touch detecting layer among the plurality of encapsulating thin films may expose a pad portion of the touch detecting layer. 
     The touch sensor may include a plurality of touch electrodes positioned at a same layer. 
     The display device may further include touch wires connected to the touch electrodes and end portions of the touch wires may form the pad portion. 
     The touch electrodes may include a plurality of first touch electrodes and a plurality of second touch electrodes, which are separated from each other, do not overlap each other, and are alternately arranged, the first touch electrodes arranged in a first direction may be connected to each other by a plurality of first connection parts, and the second touch electrodes arranged in a second direction different from the first direction may be connected to each other by a plurality of second connection parts. 
     The display device may further include an insulating layer positioned between the first connection part and the second connection part and configured to insulate the first connection part from the second connection part. 
     The first connection part may be positioned at a same layer as that of the first touch electrode and integrated with the first touch electrode and the second connection part may be positioned on a different layer from that of the second touch electrode. 
     The second connection part may be positioned on the insulating layer. 
     The touch electrode may include at least one of a dummy pattern, a protruding pattern, or a static electricity inducing pattern for protection from static electricity. 
     At least one inorganic film and at least one organic film, which are alternately stacked, may be positioned on the touch detecting layer. 
     The second connection part may include a low resistance opaque conductive material. 
     The display device may further include a second film positioned between the first film and the emission member, in which the second film may include polyimide (PI). 
     Another aspect is flexible display device including a flexible substrate, a light emission layer formed over the flexible substrate, and an encapsulation layer formed over the light emission layer and including a plurality of encapsulating thin films and a touch detecting layer configured to detect a touch input, wherein the encapsulating thin films include at least one inorganic film and at least one organic film that are alternately stacked and wherein the touch detecting layer is interposed between a selected one of the at least one inorganic film and a selected one of the at least one organic film that are adjacent to each other. 
     The touch detecting layer includes a pad portion and wherein at least one of the encapsulating thin films formed over the touch detecting layer exposes the pad portion. The touch detecting layer includes a plurality of touch electrodes formed in the same layer. The display device further includes a plurality of touch wires electrically connected to the touch electrodes, wherein the pad portion includes end portions of the touch wires. The touch electrodes include a plurality of first touch electrodes and a plurality of second touch electrodes that are spaced apart from each other, do not overlap each other, and are alternately arranged, wherein the first touch electrodes are arranged in a first direction and connected to each other via a plurality of first connection portions and wherein the second touch electrodes are arranged in a second direction crossing the first direction and connected to each other via a plurality of second connection portions. 
     The display device further includes an insulating layer interposed between the first and second connection portions. The first connection portions are formed in the same layer as the first touch electrodes and are integrated with the first touch electrodes, wherein the second connection portions are formed in a different layer from the second touch electrodes. The second connection portions are formed over the insulating layer. Each of the touch electrodes includes at least one of a dummy pattern, a protruding pattern, or a charge collection pattern. One or more of the at least one inorganic film and one of more of the at least one organic film are formed over the touch detecting layer. The touch electrodes include a plurality of first touch electrodes and a plurality of second touch electrodes that are spaced apart from each other, do not overlap each other, and are alternately arranged, wherein the first touch electrodes are arranged in a first direction and connected to each other via a plurality of first connection portions and wherein the second touch electrodes are arranged in a second direction crossing the first direction and connected to each other via a plurality of second connection portions. 
     Another aspect is a flexible display device including a flexible substrate including a first film, a light emission layer formed over the flexible substrate, an encapsulation layer formed over the light emission layer, and a touch detecting layer formed on an upper surface or a lower surface of the first film. 
     The touch detecting layer includes a plurality of touch electrodes formed in the same layer. The touch electrodes include a plurality of first touch electrodes and a plurality of second touch electrodes that are spaced apart from each other, do not overlap each other, and are alternately arranged, wherein the first touch electrodes are arranged in a first direction and connected to each other via a plurality of first connection portions and wherein the second touch electrodes are arranged in a second direction crossing from the first direction and connected to each other via a plurality of second connection portions. The display device further includes an insulating layer interposed between the first connection portions and the second connection portions. The first connection portions are formed in the same layer as the first touch electrodes and are integrated with the first touch electrodes and the second connection portions are formed in a different layer from the second touch electrodes. The second connection portions are formed over the insulating layer. The second connection portions are formed at least partially of a low resistance opaque conductive material. The touch electrodes include at least one of a dummy pattern, a protruding pattern, or a charge collection pattern. The display device further includes a second film interposed between the first film and the light emission layer, wherein the second film is formed at least partially of polyimide (PI). 
     Another aspect is a display device including a flexible substrate, a plurality of pixels formed over the substrate, an encapsulation layer formed over the pixels and including a plurality of alternately arranged organic and inorganic layers, and a touch detecting layer configured to detect a touch input, wherein at least one of the organic or inorganic layers are interposed between the touch detecting layer and the pixels. 
     The touch detecting layer includes a plurality of first touch electrodes and a plurality of second touch electrodes that are spaced apart from each other, wherein the first touch electrodes are arranged in a first direction and electrically connect to each other via a plurality of first connection portions and wherein the second touch electrodes are arranged in a second direction crossing the first direction and electrically connected to each other via a plurality of second connection portions. The touch detecting layer further includes a plurality of charge collection patterns formed between neighboring ones of the first and second touch electrodes and each of the charge collection patterns is electrically connected to one of the neighboring first and second touch electrodes and electrically insulated from the other touch electrode 
     According to at least one embodiment, it is possible to simplify the manufacturing process of the flexible display device including the touch sensor and decrease the cost thereof. 
     According to at least one embodiment, it is possible to decrease the thickness of the flexible display device including the touch sensor and improve the optical characteristics. 
     According to at least one embodiment, it is possible to decrease defects of the touch sensor and improve durability when the flexible display device is bent by preventing impurities, such as moisture, from penetrating to the touch sensor. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a block diagram of a flexible display device according to an exemplary embodiment. 
         FIG.  2    is a top plan view illustrating a touch sensor of the flexible display device according to an exemplary embodiment. 
         FIG.  3    is an enlarged view of a part of the touch sensor illustrated in  FIG.  2   . 
         FIG.  4    is a cross-sectional view illustrating the touch sensor illustrated in  FIG.  3    taken along line IV-IV. 
         FIG.  5    is a cross-sectional view of one pixel of the flexible display device according to an exemplary embodiment. 
         FIG.  6    is a cross-sectional view of an encapsulation layer of the flexible display device according to an exemplary embodiment. 
         FIG.  7    is a cross-sectional view of a base film and a touch detecting layer of the flexible display device according to an exemplary embodiment. 
         FIGS.  8  to  12 B  are drawings sequentially illustrating a manufacturing process of forming the touch sensor on or under the base film of the flexible display device according to an exemplary embodiment. 
         FIG.  13    is a top plan view of the touch sensor included in the flexible display device according to an exemplary embodiment. 
         FIG.  14    is a cross-sectional view illustrating the touch sensor illustrated in  FIG.  13    taken along line XIV-XIV. 
         FIG.  15    is a cross-sectional view illustrating the touch sensor illustrated in  FIG.  13    taken along line XV-XV. 
         FIGS.  16  and  17    are top plan views of the touch sensor included in the flexible display device according to exemplary embodiments. 
         FIG.  18    is a top plan view illustrating a touch sensor and a ground wire of a flexible display device according to an exemplary embodiment. 
         FIG.  19    is an enlarged view of a part of the flexible display device illustrated in  FIG.  18   . 
     
    
    
     DETAILED DESCRIPTION OF CERTAIN INVENTIVE EMBODIMENTS 
     Display devices providing for touch input are in wide use today across a range of portable electronic devices. The touch input is translated into touch information, such as whether an object approaches or touches the screen and the position of the touch input, by measuring changes in the physical properties of touch sensors near the screen. The touch sensors can measure changes in pressure applied to the screen, stored charge, received light, or the like when a user approaches or touches a screen with a finger or touch pen. The display device can receive different image signals based on the touch information and display images based on the received image signals. 
     Touch input can be implemented by using a touch sensor. Touch sensors can be classified based on the physical properties measured, such as resistance, capacitance, or electro-magnetic (EM) radiation. 
     For example, resistive touch sensors include two electrodes which face each other and are spaced apart from each other and can be brought into contact with each other by pressure. When the two electrodes contact each other, the touch sensor recognizes a touch position, by measuring a change in voltage based on change in resistance at the position of the contact. 
     Capacitive touch sensors include detection capacitors formed of a plurality of detecting electrodes capable of transmitting a detection signal. These sensors measure whether a touch input is generated and the position by measuring a change in the capacitance or stored change in the detection capacitor generated when a conductor, such as a finger, approaches the touch sensor. These sensors includes a plurality of touch electrodes formed in a touch detecting region and signal transmitting wires connected to the touch electrodes. The signal transmitting wires transmit a touch input signal to the touch electrodes. They also receive a detection output signal from the touch electrode generated based on the touch input and transmit the output signal to a detection signal controller. 
     Touch sensors included in flexible display devices are typically formed on a separate touch panel and attached to the flexible display device (i.e. add-on cell type sensors). The additional steps for adding a touch sensor decreases the manufacturing yield and increases the manufacturing costs. Further, an adhesive layer is formed between the touch panel and the display device, or on the touch panel, and as a result, the thickness of the display device increases. This can also decrease transmittance and increase reflectance of the display device. The wires connected to the touch sensor are vulnerable to corrosion when formed on an external side of the display. When the flexible display is bent the durability of the touch sensor and connecting electronics can be negatively impacted from the stress, resulting in the above described defects. 
     The described technology will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments are shown. As those skilled in the art would realize, the embodiments may be modified in various different ways, all without departing from the spirit or scope of the described technology. 
     In the drawings, the thicknesses of layers, films, panels, regions, etc., may be exaggerated for the sake of clarity. Like reference numerals designate like elements throughout the specification. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being “on” another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present. 
     Hereinafter, a display device and a driving method thereof according to an exemplary embodiment will be described in detail with reference to the accompanying drawings. 
     First, a flexible display device including a touch sensor will be described with reference to  FIGS.  1  to  4   . 
     Referring to  FIG.  1   , the flexible display device includes a display panel  300 , and a display controller  600  and a touch controller  700  connected to the display panel  300 . 
     The display panel  300  displays images and detects touch input. The display panel  300  includes a display area DA displaying an image and a peripheral area PA surrounding the display area DA when viewed in a plane view. 
     A portion of or the entire area of the display panel  300  is a touch active area TA capable of detecting touch input. The touch active area TA is an area capable of detecting touch input when an object approaches or touches the display panel  300 . Here, the touch input includes when an external object approaches the display panel  300  or hovers over the display panel  300 , in addition to when an external object, such as a finger of a user, is in direct contact with the display panel  300 . 
       FIG.  2    illustrates an example in which substantially the entire display area DA is the touch active area TA, but the described technology is not limited thereto. A portion of the peripheral area PA can be included in the touch active area TA or only a portion of the display area DA may serve as the touch active area TA. 
     Referring to  FIG.  1   , a plurality of pixels PX and a plurality of display signal lines (not illustrated) connected to the pixels PX are formed in the display area DA. The display signal lines apply driving signals to the pixels PX. 
     The display signal lines include a plurality of scan lines (not illustrated) applying scan signals and a plurality of data lines (not illustrated) applying data signals. The scan lines and the data lines extended in different directions which cross each other. The display signal lines extend to the peripheral area PA to form a pad portion (not illustrated). 
     In the  FIG.  1    embodiment, the pixels PX are arranged in a matrix, but the described technology is not limited thereto. Each pixel PX includes a switching element (not illustrated) connected with to gate line and the data line and a pixel electrode (not illustrated) connected to the switching element. The switching element may be a three-terminal element, such as a thin film transistor (TFT), integrated on the display panel  300 . The switching element is turned on or turned off according to the gate signal received from the gate line to selectively transmit the data signal received from the data line to the pixel electrode. The pixel PX further includes an opposite electrode (not illustrated) opposing the pixel electrode. When the display device is an organic light-emitting diode (OLED) display, an emission layer is formed between the pixel electrode and the opposite electrode to form am OLED. The opposite electrode receives a common voltage. 
     In order to implement a color display, each pixel PX displays one of the primary colors and a desired color is recognized by a sum of the primary colors. Examples of the primary color may include three primary colors, such as red, green, and blue, or four primary colors. Each pixel PX may further include a color filter positioned corresponding to each pixel electrode and filtering light to emit one of the primary colors. The emission layer included in the OLED may also emit colored light. 
     A touch sensor is formed in the touch active area TA. Touch sensors can detects touch input by various methods. For example, the touch sensors can be classified based on the physical property measured, such as resistance, capacitance, electro-magnetic (EM) radiation, and optical measurements. 
     In the embodiment of  FIG.  2   , a capacitive touch sensor will be described as an embodiment. 
     Referring to  FIG.  2   , the touch sensor includes a plurality of touch electrodes and the touch electrodes include a plurality of first touch electrodes  410  and a plurality of second touch electrodes  420 . The first and second touch electrodes  410  and  420  are separated from each other. 
     Referring to  FIG.  2   , the first and second touch electrodes  410  and  420  are alternately arranged and are formed in the touch active area TA so as not to overlap each other. The first and second touch electrodes  410  and  420  are formed in a plurality of rows and columns. 
     The first and second touch electrodes  410  and  420  are formed in the same layer. 
     Each of the first and second touch electrodes  410  and  420  can have a substantially quadrangular shape, but the described technology is not limited thereto, and the electrodes may have various forms. In some embodiments, the first and second electrodes  410  and  420  have a protrusion in order to improve sensitivity of the touch sensor. 
     The first touch electrodes  410  arranged in the same row or column are connected to or separated from each other inside or outside the touch active area TA. Similarly, the second touch electrodes  420  arranged in the same column or row are connected to or separated from each other inside or outside the touch active area TA. According to some embodiments, the first touch electrodes  410  arranged in the same row are electrically connected to each other inside the touch active area TA as illustrated in  FIG.  2    and the second touch electrodes  420  arranged in the same column are electrically connected with each other inside the touch active area TA. 
     More particularly, the first touch electrodes  410  positioned in each row are electrically connected to each other through first connection parts or first connection portions  412  and the second touch electrodes  420  positioned in each column are electrically connected to each other through second connection parts or second connection portions  422 . 
     Referring to  FIGS.  3  and  4   , the first connection parts  412  connecting adjacent first touch electrodes  410  is formed in the same layer as the first touch electrodes  410  and formed of the same material as the first touch electrodes  410 . That is, in some embodiments, the first touch electrodes  410  and the first connection parts  412  are integrated with each other and are simultaneously patterned. 
     The second connection parts  422  connecting adjacent second touch electrodes  420  are formed on a different layer from the second touch electrodes  420 . That is, the second touch electrodes  420  and the first connection parts  412  are separated from each other and can be separately patterned. The second touch electrodes  420  and the second connection parts  422  are electrically connected to each other through direct contact. 
     An insulating layer  430  is interposed between the first and second connection parts  412  and  422  to insulate the first and second connection parts  412  and  422  from each other. The insulating layers  430  are formed as a plurality of separated island-shaped insulators each formed at the intersections between the first and second connection parts  412  and  422  as illustrated in  FIGS.  3  and  4   . The insulating layer  430  exposes at least a portion of the second touch electrode  420  so that the second connection part  422  can be connected to the second touch electrode  420 . 
     The edge of the insulating layer  430  may have a round shape or may have a polygonal shape. 
     According to other embodiments, the insulating layer  430  formed over substantially the entire touch active area TA and portions of the insulating layer  430  over the second touch electrodes  420  are removed for connection between the second touch electrodes  420  adjacent in a column direction and the second connection parts  422 . 
     In contrast to the embodiments of  FIGS.  3  and  4   , a second connection part  422  connecting adjacent second touch electrodes  420  can be formed in the same layer as the first touch electrodes  410  and integrated with the first touch electrodes  410  and the first connection parts  412  connecting adjacent first touch electrodes  410  can be formed on a different layer from the first touch electrodes  410 . 
     Referring to  FIG.  2   , the first touch electrodes  410  connected to each other in each row are connected to the touch controller  700  through first touch wires  411  and the second touch electrodes  420  connected to each other in each column are connected to the touch controller  700  through second touch wires  421 . The first and second touch wires  411  and  421  are formed in the peripheral area PA of the display panel  300  as illustrated in  FIG.  2   . According to other embodiments, the first and second touch wires are formed in the touch active area TA. 
     End portions of the first and second touch wires  411  and  421  form a pad portion  450  in the peripheral area PA of the display panel  300 . 
     The first and second touch electrodes  410  and  420  have a predetermined transmittance or greater such that light can pass through the display panel  300 . For example, the first and second touch electrodes  410  and  420  may be formed of a transparent conductive material, such as a thin metal layer including indium tin oxide (ITO), indium zinc oxide (IZO), silver nano wire (AgNw), metal mesh, or carbon nano tube (CNT), but they not limited thereto. 
     The first and second touch wires  411  and  421  may include the transparent conductive material included in the first and second touch electrodes  410  and  420 , or a low resistance material, such as molybdenum (Mo), silver (Ag), titanium (Ti), copper (Cu), aluminum (Al), or molybdenum/aluminum/molybdenum (Mo/Al/Mo). 
     The first and second touch electrodes  410  and  420 , which are adjacent to each other, form a mutual sensing capacitor serving as the touch sensor. The mutual sensing capacitor receives a detection input signal through one of the first and second touch electrodes  410  and  420  and outputs a change in stored charge as a detection output signal from the other of the first and second touch electrodes  410  and  420 . The charge stored in the mutual sensing capacitor is changed due to the touch input of an external object. 
     In contrast to the embodiments of  FIGS.  2  to  4   , the first and second touch electrodes  410  and  420  may be separated from each other and electrically connected to the touch controller  700  through touch wires (not illustrated). In these embodiments, each touch electrode forms a self-sensing capacitor as the touch sensor. The self-sensing capacitor receives the detection input signal and is charged to a predetermined charge amount. When an external object, such as a finger, touches the touch sensor the predetermined charged charge is changed and the self-sensing capacitor outputs a detection output signal different from the detection input signal. 
     Referring back to  FIG.  1   , the display controller  600  controls the image display operation of the display panel  300 . 
     More particularly, the signal controller  600  receives an input image signal containing luminance information for each pixel PX and an input control signal controlling the display of the input image signal from an external source. The signal controller  600  processes the input image signal based on the input control signal to convert the processed input image signal to an output image signal. The signal controller then generates a control signal, such as a gate control signal and a data control signal. The signal controller  600  transmits the gate control signal to a gate driver (not illustrated) and transmits the data control signal and the output image signal to a data driver (not illustrated). 
     Although not illustrated, the data driver receives the output image signals for the pixels PX of one row according to the data control signal, selects a grayscale voltage corresponding to each of the output image signal, converts the output image signals to data voltages, and then applies the converted data voltages to corresponding data lines. The gate driver turns on the switching element connected to the gate line by applying a gate-on voltage to the gate line according to the gate control signal. Then, the data voltage applied to the data line is applied to the corresponding pixel PX through the turned-on switching element. When the data voltage is applied to the pixel PX, the pixel PX emits light with a luminance corresponding to the data voltage through various optical conversion devices, such as an OLED. 
     The touch controller  700  is connected to the touch sensor formed in the touch active area and controls the operation of the touch sensor. The touch controller  700  transmits the detection input signal to the touch sensor and receives and process the detection output signal. The touch controller  700  generates touch information, such as whether touch input has occurred and the corresponding touch position, by processing the detection output signal. 
     The driving devices, such as the data driver, the gate driver, and the display controller  600 , may be directly mounted on the display panel  300  in the form of at least one integrated circuit chip, may be mounted on a flexible printed circuit film (not illustrated) to be attached onto the display panel  300  in the form of a tape carrier package (TCP), or may be mounted on a separate printed circuit board (PCB) (not illustrated). Alternatively, the driving device may be integrated with the display panel  300  together with the display signal lines, the switching element, and the like. 
     The touch controller  700  may also be directly mounted onto the display panel  300  in the form of at least one integrated circuit chip, may be mounted on a flexible printed circuit film to be attached onto the display panel  300  in the form of a TCP, or may be mounted on a separate PCB. The touch controller  700  may be connected to the first touch wire  411  and the second touch wire  421  through the pad portion  450  of the display panel  300 . 
     Next, the structure of the flexible display device will be described with reference to  FIGS.  5  and  6    together with the aforementioned  FIGS.  1  to  4   . 
       FIG.  5    is a cross-sectional view of one pixel of the flexible display device according to an exemplary embodiment.  FIG.  6    is a cross-sectional view of an encapsulation layer of the flexible display device according to an exemplary embodiment. 
     Referring to  FIG.  5   , the flexible display device includes a flexible substrate, and the flexible substrate may include various plastics, a metal thin film, ultrathin glass, or the like. According to some embodiments, the flexible substrate includes at least one plastic film. The plastic film may include, for example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), polyarylate (PAR), polyetherimide (PEI), polyethersulfone (PES), or polyimide (PI). 
       FIG.  5    illustrates an example in which the flexible substrate includes a first film  112  and a second film  113 . For example, the first film  112  may include polyimide (PI) having excellent moisture proofing performance and the second film  113  may include polyethylene terephthalate (PET) as a base film. The first film  112  is formed on the second film  113 . In some embodiment, the second film  113  is omitted. 
     A barrier layer  111  is formed on the first film  112 . The barrier layer  111  prevents impurities from penetrating through the flexible substrate and permeating to an upper side of the barrier layer  111 . The top surface of the barrier layer can be flat. The barrier layer  111  can include at least one of an inorganic layer or an organic layer. For example, the barrier layer  111  can include silicon nitride (SiNx), silicon oxide (SiOx), or silicon oxynitride (SiOxNy). The barrier layer  111  may be omitted in some embodiments. 
     A display device including a plurality of thin films is formed on the barrier layer  111 . The display device includes the aforementioned various signal lines and wires and the pixels PX. The signal lines include the scan lines applying scan signals and the data lines applying data signals. 
     An embodiment of the display device will be described with reference to  FIG.  5   . A plurality of active layers  154   b  are formed on the barrier layer  111 . The active layer  154   b  includes a channel region  152   b , and a source region  153   b  and a drain region  155   b  formed at both sides of the channel region  152   b . The source and drain regions  153   b  and  155   b  are formed by doping the active layer  154   b . The active layer  154   b  may be formed of amorphous silicon, polysilicon, or an oxide semiconductor. 
     A gate insulating layer  140  formed of silicon nitride (SiNx), silicon oxide (SiOx) or the like is formed on the active layer  154 . 
     The scan lines (not illustrated) and a plurality of gate conductors including a control electrode or gate electrode  124   b  are formed on the gate insulating layer  140 . The gate electrode  124   b  substantially overlaps a portion of the active layer  154   b , particularly, the channel region  152   b.    
     A first passivation layer  180   a  is formed on the gate insulating layer  140  and the gate conductor. The first passivation layer  180   a  and the gate insulating layer  140  include a contact hole  183   b  through which the source region  153   b  of the active layer  154   b  is exposed and a contact hole  185   b  through which the drain region  155   b  is exposed. 
     A plurality of data conductors including the data lines  171 , a plurality of input electrodes  173   b , and a plurality of output electrodes  175   b  are formed on the first passivation layer  180   a . The data line  171  transmits a data signal and crosses the scan line. The input electrode  173   b  is connected to the data line  171 . The output electrode  175   b  may have an island shape and is separated from the data line  171 . The input electrode  173   b  and the output electrode  175   b  face each other on opposing sides of the active layer  154   b.    
     The input electrode  173   b  and the output electrode  175   b  are respectively electrically connected to the source region  153   b  and the drain region  155   b  of the active layer  154   b  through the contact holes  183   b  and  185   b.    
     The control electrode  124   b , the input electrode  173   b , and the output electrode  175   b  form a driving thin film transistor Qd together with the active layer  154   b . However, the structure of the driving thin film transistor Qd is not limited thereto and may be variously changed. 
     A second passivation layer  180   b  formed of an inorganic insulating material, such as silicon nitride or silicon oxide, is formed on the data conductor. The second passivation layer  180   b  has a substantially flat surface without any steps in order to improve the light emitting efficiency of a light emitting member to be formed thereon. The second passivation layer  180   b  has a contact hole  185   c  through which the output electrode  175   b  is exposed. 
     A plurality of pixel electrodes  191  are formed on the second passivation layer  180   b.    
     The pixel electrode  191  of each pixel PX is physically and electrically connected to the output electrode  175   b  through the contact hole  185   c  in the second passivation layer  180   b . The pixel electrode  191  may be formed of a transflective conductive material or a reflective conductive material. 
     A pixel defining layer (also referred to as a partition wall)  360  having a plurality of openings through which the pixel electrodes  191  are exposed is formed on the second passivation layer  180   b . The openings in the pixel defining layer  360  through which the pixel electrodes  191  are exposed define each of the pixel regions. The pixel defining layer  360  may be omitted in some embodiments. 
     An emission member or light emission layer  370  is formed on the pixel defining layer  360  and the pixel electrode  191 . The emission member  370  includes a first organic common layer  371 , a plurality of emission layers  373 , and a second organic common layer  375  which are sequentially stacked. 
     The first organic common layer  371  may include, for example, at least one of a hole injecting layer and a hole transport layer which are sequentially stacked. The first organic common layer  371  may be formed over substantially the entire surface of the display area in which the pixels PX are formed or may be formed only in the area of each pixel PX. 
     The emission layers  373  are formed on the pixel electrodes  191  of the corresponding pixels PX. The emission layer  373  may be formed of an organic material uniquely emitting light of one of the primary colors, such as red, green, or blue, or may have a structure in which a plurality of organic material layers emitting light of different colors are stacked. 
     The second organic common layer  375  may include, for example, at least one of an electron transport layer and an electron injecting layer which are sequentially stacked. The second organic common layer  375  may be formed over substantially the entire surface of the display area in which the pixels PX are arranged or may be formed only in the area of each pixel PX. 
     The first and second organic common layers  371  and  375  improve the light emission efficiency of the emission layer  373  and any one of the first and second organic common layers  371  and  375  may be omitted. 
     An opposite electrode  270  applying the common voltage is formed on the emission member  370 . The opposite electrode  270  may include a transparent conductive material. For example, the opposite electrode  270  may be formed of a transparent conductive material, or may be formed by thinly stacking a metal, such as calcium (Ca), barium (Ba), magnesium (Mg), aluminum (Al), or silver (Ag), thereby having light transmission properties. 
     The pixel electrode  191 , the emission member  370 , and the opposite electrode  270  of each pixel PX form an OLED and one of the pixel electrode  191  and the opposite electrode  270  serves as a cathode and the other serves as an anode. 
     According to some embodiments, the flexible display device is a top emission type display which emits internal light from the emission member  370  in an upward direction to display an image. 
     An encapsulation layer  280  is formed on the opposite electrode  270 . The encapsulation layer  280  prevents moisture and/or oxygen from penetrating from the environment by encapsulating the emission member  370  and the opposite electrode  270 . 
     The encapsulation layer  280  includes a plurality of encapsulating thin films. 
     Referring to  FIG.  6   , the plurality of encapsulating thin films of the encapsulation layer  280  include at least one inorganic film  280 _ 1  and at least one organic film  280 _ 2 , and the at least one inorganic film  280 _ 1  and the at least one organic film  280 _ 2  may be alternately stacked. The inorganic film  280 _ 1  includes an inorganic material, such as aluminum oxide (AlOx), silicon oxide (SiOx), or silicon nitride (SiNx).  FIG.  6    illustrates an embodiment in which the inorganic film  280 _ 1  is formed at the lowermost side and the uppermost side of the encapsulation layer  280 , but the described technology is not limited thereto. The organic film  280 _ 2  may be formed on the lowermost side or the uppermost side of the encapsulation layer  280 . 
     The touch sensor and a touch detecting layer  400  including the touch wires  411  and  412  connected to the touch sensor are formed inside the encapsulation layer  280  according to the embodiment of  FIG.  6   . That is, the touch detecting layer  400  is interposed between the encapsulating thin films of the encapsulation layer  280 . More particularly, the touch detecting layer  400  is interposed between the organic film  280 _ 2  and the inorganic film  280 _ 1  of the encapsulation layer  280  which are adjacent to each other. 
       FIG.  6    illustrates an embodiment in which the touch detecting layer  400  is formed directly above the inorganic film  280 _ 1  near the upper side of the encapsulating thin films of the encapsulation layer  280 , but the described technology is not limited thereto. The touch detecting layer  400  may be formed directly above the organic film  280 _ 2  and the touch detecting layer  400  may be formed directly above another inorganic film  280 _ 1 . 
     When the touch detecting layer  400  is interposed between the encapsulating thin films near a lower side of the encapsulation layer  280 , interference may be generated due to parasitic capacitance between the touch detecting layer  400  and the display device formed at the lower side. Accordingly, in some embodiments, the dielectric constant of the encapsulating thin films of the encapsulation layer  280 , particularly, the encapsulating thin films formed under the touch detecting layer  400  are selected to be relatively low. 
     As described above, at least one encapsulating thin film is formed in each of an upper portion and a lower portion of the touch detecting layer  400  included in the encapsulation layer  280  so that it is possible to block moisture and/or oxygen from penetrating to the touch detecting layer  400  from the environment. 
     In order to protect the touch detecting layer  400 , at least one inorganic film  280 _ 1  and at least one organic film  280 _ 2 , which are alternately stacked, are formed above the touch detecting layer  400 . 
     A portion of the encapsulating thin film formed at an upper portion of the pad portion  450  of the touch wire included in the touch detecting layer  400  is removed, so that the pad portion  450  is exposed. The touch controller  700  is electrically connected to the pad portion  450 . 
     The touch detecting layer  400  is formed by sequentially stacking the encapsulating thin films and forming the touch electrodes and the touch wires by stacking a conductive material for the touch electrodes and the touch wires on the encapsulating thin films by a method, such as sputtering, and patterning and printing the conductive material. Next, the remaining encapsulating thin films are stacked on the touch detecting layer  400  and the encapsulating thin films on the touch detecting layer  400  are patterned, so that a region of the upper portion of the pad portion  450 , in which the encapsulating thin film is removed, can be formed. Alternatively, the encapsulating thin film can be stacked only on a region excluding the pad portion  450  by using a mask when the remaining encapsulating thin films are stacked on the touch detecting layer  400 . 
     A detailed structure of the touch sensor included in the touch detecting layer  400  is the same as described above, and thus, a detailed description thereof will be omitted. 
     As described above, the touch detecting layer  400  including the touch sensor is formed together during the process of forming the encapsulation layer  280 , so that it is not necessary to separately manufacture and attach the touch panel. Accordingly, it is possible to simplify the manufacturing process of the flexible display device including the touch sensor and thereby decrease the manufacturing cost. Further, it is not necessary to attach a separate touch panel onto the display panel on which an image is displayed, so that it is possible to decrease the thickness of the flexible display device including the touch sensor and improve the optical characteristics, such as transmittance. 
     Since the touch sensor is included in the encapsulation layer  280 , it is possible to prevent moisture and/or oxygen from penetrating to the touch sensor, and thus, improve the moisture-proofing of the display device. Further, defects in the touch sensor due to corrosion of the metal can be decreased and the bending durability of the flexible display device can be improved. 
     The touch electrodes included in the touch sensor are formed in the same layer, so that it is possible to decrease deformation of the touch sensor and prevent defects of the touch sensor when the display panel  300  is bent. It is also possible to decrease the thickness of the touch detecting layer  400  and decrease the bending curvature radius of the display device. 
     A reflection prevention layer  390  capable of decreasing reflection of ambient light may be further formed on the encapsulation layer  280 . 
     Next, the flexible display device according to an exemplary embodiment will be described with reference to  FIG.  7    together with the aforementioned  FIGS.  1  to  6   . 
       FIG.  7    is a cross-sectional view of a base film and a touch detecting layer of the flexible display device according to an exemplary embodiment. 
     Referring to  FIG.  7   , the flexible display device is substantially the same as the aforementioned flexible display device illustrated in  FIGS.  1  to  6    except for the position of the touch detecting layer  400 . The touch detecting layer  400  according to the  FIG.  7    embodiment is formed on an upper surface of a second film  113  that is a flexible substrate as illustrated in  FIG.  7 A  or is formed on a lower surface of the second film  113  as illustrated in  FIG.  7 B . That is, a plurality of touch electrodes  410  and  420  forming a touch sensor and touch wires  411  and  421  connected to the touch electrodes  410  and  420  are formed on or under the second film  113 . 
     According to some embodiments, the flexible display device is a bottom emission type which emits light from an emission member  370  in a downward direction and displays an image. In these embodiments, a first film  112  and a barrier layer  111  have high transparency. 
     The effects of the embodiment of  FIG.  7    are substantially the same as those of the aforementioned exemplary embodiment. 
     Next, a method of manufacturing the touch detecting layer  400  of the flexible display device according to an exemplary embodiment will be described with reference to  FIGS.  8  to  12 B  together with the aforementioned drawings. 
     First, referring to  FIG.  8   , a conductive material is stacked on the second film  113 , such as PET, by a method, such as sputtering, to form a conductive layer. The conductive layer includes a first conductive layer  401  and a second conductive layer  403  which are sequentially stacked. The first conductive layer  401  includes a transparent conductive material, such as ITO or IZO, and the second conductive layer  403  includes a metal material, such as aluminum (Al). 
     Next, referring to  FIGS.  9 A and  9 B , a first intermediate pattern  410 P, a second intermediate pattern  420 P, a second connection pattern  422 P, and touch wires including the first and second touch wires  411  and  421  respectively connected to the first and second intermediate patterns  410 P and  420 P are formed by patterning the first conductive layer  401  and the second conductive layer  403 . The shape of each of the first and second intermediate patterns  410 P and  420 P may be the same as the aforementioned first and second touch electrodes  410  and  420 . 
     The second intermediate patterns  420 P formed in the same column are connected to each other through the second connection patterns  422 P formed in the same layer as the second intermediate patterns  420 P and patterned together with the second intermediate patterns  420 P. In contrast, the first intermediate patterns  410 P formed in the same row are connected to each other through separate first connection patterns (not illustrated). 
     Next, referring to  FIGS.  10 A and  10 B , a plurality of transparent touch electrodes  410 , a plurality of transparent second touch electrodes  420 , and a plurality of second connection parts  422  are formed by removing the second conductive layer  403 , which is an upper layer of the first intermediate pattern  410 P, the second intermediate pattern  420 P, and the second connection pattern  422 P by an etching method, or the like. In contrast, when the first touch electrodes  410  arranged in the same row are connected through the first connection parts  412  formed the same layer, the first connection parts  412  are formed instead of the second connection parts  422  in this step. 
     The first touch wire  411  and the second touch wire  421  may still include all of the first conductive layer  401  and the second conductive layer  403  to form low resistance wires. 
     Next, referring to  FIGS.  11 A and  11 B , an insulating layer  430  formed on the second connection part  422  and covering the second connection part  422  and an insulating layer  432  formed on the touch wire and covering the touch wire are formed by stacking an insulating material on the first touch electrode  410 , the second touch electrode  420 , the second connection part  422 , and the touch wire and patterning the insulating material. 
     Referring to  FIGS.  12 A and  12 B , the first connection part  412  insulated from and crossing the second connection part  422  and connecting the first touch electrodes  410 , which are adjacent to each other in one row, is then formed by stacking a conductive material on the insulating layer  430  and patterning the conductive material. 
     Accordingly, the touch detecting layer  400  including the touch sensor is completed. The manufacturing method of the touch detecting layer  400  according to the embodiment of  FIGS.  8  to  12 B  can be applied to an exemplary embodiment in which the touch sensor is formed on or under the second film  113  like the aforementioned exemplary embodiment illustrated in  FIGS.  1  to  5   , and  FIG.  7   . 
     The manufacturing method of the touch detecting layer  400  according to the embodiment of  FIGS.  8  to  12 B  can also be applied to an embodiment in which the touch detecting layer  400  is formed inside the encapsulation layer  280  like the aforementioned exemplary embodiment illustrated in  FIGS.  1  to  6   . In these embodiments, the second film  113  illustrated in  FIGS.  8  to  12 B  is replaced with any one inorganic film  280 _ 1  of the encapsulation layer  280 . 
     Now, various structures of the touch sensor included in the flexible display device according to exemplary embodiments will be described with reference to  FIGS.  13  to  17   . 
     Referring to  FIG.  13   , the touch sensor is substantially the same as that of the aforementioned exemplary embodiment, except it further includes a structure for protection from static electricity. The features different from those of the aforementioned exemplary embodiment illustrated in  FIGS.  2  to  4    will be mainly described. 
     Adjacent first touch electrodes  410  formed in the same row are connected to each other by first connection parts  412  which are formed in the same layer as the first touch electrodes  410 . The first connection parts  412  may be integrated with the first touch electrodes  410 . 
     First, referring to  FIGS.  13  and  14   , adjacent second touch electrodes  420  formed in the same column are connected to each other by second connection parts  422  which are formed on a different layer from that of the second touch electrodes  420 . The second touch electrodes  420  and the second connection parts  422  are connected to each other through direct contact. There are a plurality of second connection parts  422  connecting each pair of second touch electrodes  420 .  FIG.  13    illustrates an example in which one pair of second connection parts  422  connects the adjacent second touch electrodes  420 . 
     An insulating layer  430  is formed between the first and second connection parts  412  and  422  to insulate the first and second connection parts  412  and  422  from each other. The insulating layers  430  include a plurality of separate island-shaped insulators formed near the intersections between the first and second connection parts  412  and  422  as illustrated in  FIG.  13   . In some embodiments, the insulating layer  430  is formed over substantially the entire touch active area TA and portions of the insulating layer  430  are removed so as to expose portions of the second touch electrode  420  so that the second connection parts  422  can be connected to one pair of connected second touch electrodes  420 . 
     The second connection parts  422  are formed of a transparent conductive material or a low resistance opaque conductive material such as metal. When the second connection parts  422  are formed of a low resistance opaque metal material, the second connection part  422  may be formed in the same layer as the touch wires  411  and  421  of the peripheral area PA and in the same manufacturing process. In order to prevent the second connection parts  422  formed of the low resistance opaque metal material from being observed, the widths of the second connection parts  422  are less than a predetermined width. Alternatively, the second connection part  422  may be designed to be inclined in an oblique direction with respect to horizontal. As described above, when the second connection parts  422  are designed to be narrow in consideration of their visibility, defects may be generated in the second connection parts  422  due to static electricity or charge build up at the intersection between the first and second connection parts  412  and  422 . 
     In order to prevent static electricity build up, dummy patterns  418 ,  419 ,  428 , and  429 , each having an island shape, are electrically insulated from the touch electrodes  410  and  420  to which the dummy patterns  418 ,  419 ,  428 , and  429  belong. The dummy patterns  418 ,  419 ,  428 , and  429  are formed to be adjacent to the intersections between the first and second touch electrodes  410  and  420  and are formed in partial regions of at least one of the first and second touch electrodes  410  and  420 . As illustrated in  FIG.  13   , the first dummy pattern  418  is spaced apart from an edge of the first touch electrode  410  and the second dummy pattern  419  contacts the edge of the first touch electrode  410  and is formed in a partial region of the first touch electrode  410 . Similarly, the first dummy pattern  428  is spaced apart from an edge of the second touch electrode  420  and the second dummy pattern  429  contacts the edge of the second touch electrode  420  and is formed in a partial region of the second touch electrode  420 . 
     The dummy patterns  418 ,  419 ,  428 ,  429  form blocking regions (insulating regions) in the current flow path of the first touch electrode  410  or the second touch electrode  420  to decrease the width of the current flow path and increase the length of the path. Thus, it is possible to prevent static electricity from rapidly flowing into a high resistance region, i.e. the crossing region between the first and second touch electrodes  410  and  420 , by increasing the electrical resistance on the current flow path. 
     Referring to  FIG.  13   , the dummy patterns  418  and  428  are spaced apart from the edges of the touch electrodes  410  and  420  to which the dummy patterns  418  and  428  belong. The dummy patterns  419  and  429  contact the edges of the touch electrodes  410  and  420  to which the dummy patterns  419  and  429  belong. When positively charged static electricity collects in the dummy patterns  418  and  428 , negative charge collects on surfaces of the dummy patterns  418  and  428  to pull the positive charges of the static electricity. Thus, the effects of the static electricity flowing into the second connection part  422  can be relieved. The dummy patterns  419  and  429  extend the current flow path and make the lengthens the flow of current so as to prevent the inflow current from rapidly flowing into the crossing region of the first and second touch electrodes  410  and  420 . 
     The dummy patterns  418 ,  419 ,  428 ,  429  are formed in the same layers as the first and second touch electrodes  410  and  420  and are formed of the same material as the first and second touch electrodes  410  and  420 . 
     The dummy patterns  418 ,  419 ,  428 ,  429  may be formed with the same size and shape, which are symmetrical to each other with respect to the row and column directions of the first and second touch electrodes  410  and  420 . For example, the first and second dummy patterns  418  and  419  of the first touch electrode  410  are formed with the same size and are symmetrical to each other based on the first connection part  412 . The first and second dummy patterns  428  and  429  of the second touch electrode  420  are formed with the same size and are symmetrical to each other based on the second connection part  422 . 
     The dummy patterns  418 ,  419 ,  428 , and  429  may have a bent shape so as to form a current flow path within the touch electrodes  410  and  420 . For example, in the second touch electrode  420 , the second dummy patterns  429  may be positioned at edges of both sides of the second touch electrode  420  and the first dummy pattern  428  having a substantially L or reverse L-shape may be positioned between the second dummy patterns  429 . 
     The shapes and positions of the dummy patterns  418 ,  419 ,  428 ,  429  are not limited to those illustrated in the figures and may be variously changed. 
     The second touch electrode  420  has a protruding pattern  420  protruding toward the adjacent first touch electrode  410  and connected to the second connection part  422 . The protruding pattern  427  prevents static electricity from rapidly flowing into the second connection part  422  which has a relatively very small width and has a shape limiting the current flow paths of the touch electrodes  410  and  420  together with the dummy patterns  418 ,  419 ,  428 , and  429 . A plurality of protruding patterns  427  are formed in one second touch electrode  420  and extend in parallel in opposite directions from the second touch electrodes  420  the protruding patterns  427  are connected to. 
       FIG.  13    illustrates an example in which the protruding patterns  427  protrude from the second touch electrodes  420 , which are separated from each other and are connected to the second connection parts  422 . In other embodiments, the adjacent first touch electrodes  410  are connected to each other through the first connection part  412  formed in a different layer from the first touch electrodes  410 , and in these embodiments, the first touch electrodes  410  have a protruding pattern (not illustrated) connected to the first connection parts  412 . 
     Referring to  FIGS.  13  and  15   , the touch sensor further includes a plurality of static electricity inducing patterns or charge collection patterns  490 . The static electricity inducing patterns  490  are electrically connected to any one of the first and second touch electrodes  410  and  420  and extend in a direction toward the touch electrode  410  or  420  adjacent to the one touch electrode  410  or  420  to which the static electricity inducing pattern  490  is connected. Thus, a partial region of the static electricity inducing patterns  490  substantially overlaps the adjacent touch electrode  410  or  420 . The static electricity inducing patterns  490  are connected to any one of the touch electrodes  410  and  420  through direct contact. In other embodiments, the static electricity inducing patterns  490  are electrically connected to the touch electrode  410  or  420  through a contact hole (not illustrated) formed in an insulating layer  434  and are formed on an upper or lower layer of the touch electrode  410  or  420  connected to the static electricity inducing patterns  490 . 
     Here, the insulating layer  434  is interposed between the touch electrode  410  or  420  not electrically connected to the static electricity inducing patterns  490  and overlap the static electricity inducing patterns  490 . 
     The static electricity inducing patterns  490  are formed of the same material and in the same layer as the second connection parts  422  for simplification of manufacturing. In some embodiments, the static electricity inducing pattern  490  is formed of a low resistance opaque metal material like the touch wires  411  and  421 . 
     When static electricity is induced in the static electricity inducing pattern  490 , it is possible to secure stability for the first and second connection parts  412  and  422 , and even when the static electricity inducing patterns  490  incur damage, the damage to the patterns does not exert an influence on the driving of the touch sensor. 
     Next, referring to  FIG.  16   , a touch sensor according to another embodiment includes only first dummy patterns  418  and  428  and protruding patterns  427  without the aforementioned second dummy patterns  419  and  429  and static electricity inducing pattern  490  of the touch sensor illustrated in  FIGS.  13  to  15   . 
     The first touch electrodes  410  include the first dummy patterns  418  and the second touch electrodes  420  include the first dummy patterns  428  and the protruding patterns  427 . The first dummy patterns  428  and the protruding patterns  427  have a substantially L or reverse L-shape. 
     The bent protruding pattern  427  increases the length of the current flow path between the second touch electrodes  420 . 
     Referring to  FIG.  17   , a touch sensor according to another embodiment includes only first dummy patterns  418  and  428  and second dummy patterns  429  without the aforementioned protruding patterns  427  and static electricity inducing pattern  490  of the touch sensor illustrated in  FIGS.  13  to  15   . 
     The first touch electrodes  410  include the first dummy patterns  418  and the second touch electrodes  420  are electrically connected by a single second connection part  422  without a protruding pattern and include the first dummy patterns  428  and the second dummy patterns  429 . The first and second connection parts  412  and  422  are oblique in a diagonal direction. 
     The number, shapes, and positions of the various dummy patterns, the protruding patterns, and the static electricity inducing patterns may be various combined, and variously modified if necessary. 
     Next, a flexible display device according to an exemplary embodiment will be described with reference to  FIGS.  18  and  19   . 
       FIG.  18    is a top plan view illustrating a touch sensor and a ground wire of the flexible display device according to an exemplary embodiment.  FIG.  19    is an enlarged view of a portion of the flexible display device illustrated in  FIG.  18   . 
     The flexible display device is the same as that of the aforementioned exemplary embodiment, expect it further includes a ground wire  60  formed in a peripheral area PA. 
     The ground wire  60  is formed in outer peripheral areas of touch wires  411  and  421 . The ground wire  60  is formed along the border of the display panel  300  surrounding the touch wires  411  and  421 . For example, the ground wire  60  may have a substantially quadrangular shape. 
     The ground wire  60  is electrically connected to a ground power source in order to remove static electricity flowing-in to the touch active area TA from the environment. To this end, the ground wire  60  is electrically connected to the ground power source through a pad included in a pad portion  450 . 
     Referring to  FIG.  19   , the ground wire  60  includes at least one static electricity inducing part  70 . The static electricity inducing part  70  may be more densely formed in corner areas than non-corner areas of the ground wire  60 . 
     The static electricity inducing part  70  includes a plurality of static electricity inducing patterns  71 ,  72 ,  73 ,  74 , and  75 . The static electricity inducing patterns  71 ,  72 ,  73 ,  74 , and  75  have shapes protruding from the ground wire  60  and extend toward the outside from the ground wire  60  in order to induce static electricity flowing-in from the environment. 
     The static electricity inducing patterns  71 ,  72 ,  73 ,  74 , and  75  have a lightning rod shape in order to induce external static electricity. Further, in order to improve the static electricity inducing effect, concave-convex portions  77  can be formed in at least one of the static electricity inducing patterns  71 ,  72 ,  73 ,  74 , and  75 . In some embodiments, the concave-convex portions  77  having concave-convex shapes are formed in the static electricity inducing patterns  71  and  75 . The number of static electricity inducing patterns  71 ,  72 ,  73 ,  74 , and  75  illustrated in  FIG.  19    can be variously changed. Further, lengths of the static electricity inducing patterns  71 ,  72 ,  73 ,  74 , and  75  may be different from or the same as each other. 
     The static electricity inducing patterns  71 ,  72 ,  73 ,  74 , and  75  are integrally formed with the ground wire  60 . 
     While the described technology has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the described technology is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.