Display device including a touch sensor and method of manufacturing the same

Abstract

According to various embodiments of the present invention, there are provided a display device including a touch sensor and a method of manufacturing the same. The display device includes: a substrate having a display area and a pad area; a packaging layer disposed on the substrate and including a first inorganic film and a first organic film; a touch buffer layer disposed on the packaging layer; a touch sensing unit disposed on the touch buffer layer, including a bridging portion disposed on the touch buffer layer, a touch insulating film disposed on the bridging portion, and a first touch electrode and a second touch electrode disposed on the touch insulating film; a touch driving line disposed on the touch insulating film and connected to one of the first touch electrode and the second touch electrode; a touch sensing line disposed on the touch insulating film and connected to the other of the first touch electrode and the second touch electrode; and a touch pad disposed in the pad area, including an upper pad electrode and a lower pad electrode.

Description

[0001] This application is a divisional application of the invention patent application with the application number 201811242040.1.

[0002] This application claims priority to Korean Patent Application No. 10-2017-0144326, filed with the Korean Intellectual Property Office on October 31, 2017. Technical Field

[0003] The present invention relates to a display device including a touch sensor and a method of manufacturing the display device. Background Art

[0004] With the development of an information-oriented society, the demand for various display devices for displaying images has been gradually increasing. Recently, various display devices such as liquid crystal display (LCD) devices, plasma display panel (PDP) devices, and organic light emitting display (OLED) devices have been developed and applied.

[0005] Among these display devices, organic light emitting display devices have recently received considerable attention due to their self-emitting characteristics, high response speed, wide viewing angle, high contrast ratio, improved color gamut, and thinner form factor.

[0006] In addition, these display devices are operated by user instructions input via various input devices such as a keyboard, a mouse, etc. And, as one of the input devices, a touch panel display device has been developed so that a user can intuitively and conveniently input instructions by touching the screen of the display device with a dedicated stylus or one or more fingers. The touch panel is disposed on the screen of the display device, and then the user can input an instruction to the display device by touching a certain point on the screen of the display device. Since the touch panel detects touch coordinates, it may be referred to as a touch sensing unit.

[0007] In addition, the display device includes a display area for displaying an image and a border area corresponding to an edge area of the display area. Recently, due to reasons such as design, an attempt has been made to reduce the width of the border area. However, in the case of mounting the touch panel on the display device, there are some limitations in reducing the width of the border area because the number of signal lines for transmitting touch signals and thus outputting the touch signals to the outside is further increased. Summary of the Invention

[0008] An object of some embodiments of the present invention is to provide a display device including a touch sensor and a method of manufacturing the display device, which can simplify a process.

[0009] Another object of some embodiments of the present invention is to provide a display device including a touch sensor and a method of manufacturing the display device, which can reduce a border area by reducing process variations.

[0010] According to an aspect consistent with embodiments of the present invention, a display device is provided, including: a substrate having a display area and a pad area; an encapsulation layer disposed on the substrate and including a first inorganic film and a first organic film; a touch buffer layer disposed on the encapsulation layer; a touch sensing unit disposed on the touch buffer layer, the touch sensing unit including a bridging portion disposed on the touch buffer layer, a touch insulating film disposed on the bridging portion, and a first touch electrode and a second touch electrode disposed on the touch insulating film; a touch driving line disposed on the touch insulating film and connected to one of the first touch electrode and the second touch electrode; a touch sensing line disposed on the touch insulating film and connected to the other of the first touch electrode and the second touch electrode; and a touch pad disposed in the pad area, the touch pad including an upper pad electrode and a lower pad electrode.

[0011] According to another aspect consistent with embodiments of the present invention, a display device is provided, including: a substrate having a display area and a pad area for applying signals to the display area; an encapsulation layer disposed in the display area and including a first inorganic film, a second inorganic film disposed on the first inorganic film, and a first organic film disposed between the first inorganic film and the second inorganic film; a touch buffer layer disposed on the encapsulation layer; and a touch sensing unit disposed on the touch buffer layer and including a touch sensor, wherein at least one of the first inorganic film and the second inorganic film is disposed in a part of the pad area and the touch buffer layer is disposed on the at least one inorganic film.

[0012] According to still another aspect consistent with embodiments of the present invention, a method of manufacturing a display device is provided, including: disposing a first inorganic film on a substrate; disposing a first organic film on the first inorganic film; disposing a second inorganic film on the first organic film; and forming a touch buffer layer on the second inorganic film. Further, a touch electrode is patterned on the touch buffer layer, and when patterning the touch electrode, at least one of the first inorganic film and the second inorganic film and the touch buffer layer are patterned.

[0013] According to some embodiments of the present invention, a display device including a touch sensing unit and a method of manufacturing the display device, which can simplify the process and reduce the manufacturing cost, are provided.

[0014] According to some embodiments of the present invention, a display device including a touch sensing unit and a method of manufacturing the display device, which can reduce the size of a non-display area by reducing the process margin deviation, are provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a view illustrating a display device according to some embodiments of the present invention;

[0016] Figure 2 is a circuit diagram of a pixel according to some embodiments of the present invention;

[0017] Figure 3 is a plan view of a touch sensing unit according to some embodiments of the present invention;

[0018] Figure 4 is a plan view of a touch sensing unit according to some embodiments of the present invention;

[0019] Figures 5 to 9 is a cross-sectional view of a manufacturing process according to some embodiments of the present invention;

[0020] Figures 10 to 14 is a cross-sectional view of a manufacturing process of a pad region and a display region adjacent to the pad region in a display device according to some embodiments of the present invention;

[0021] Figure 15 is a flowchart of a method of manufacturing a display device according to some embodiments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. When referring to the elements of the drawings by reference numerals, the same reference numerals refer to the same elements even though they are shown in different drawings. In the following description of the present invention, when a detailed description of known functions and configurations related thereto would obscure the subject matter of the present invention, the detailed description thereof will be omitted.

[0023] Here, terms such as "first", "second", "A", "B", "(a)", or "(b)" may be used to describe elements of the present invention. Each of these terms is not used to define the essence, rank, order, or number of the elements, but is only used to distinguish the corresponding elements from other elements. When an element is referred to as being "connected to" or "coupled to" another element, it should be construed that, in addition to one element being directly connected to or coupled to another element, other elements may be "interposed" between these elements or these elements may be "connected" or "coupled" to each other via other elements.

[0024] Figure 1 is a view illustrating a display device according to some embodiments of the present invention.

[0025] Refer to Figure 1, the display device 1 may include a display panel 11, a touch sensing unit 12, a display driver 14a, a touch driver 14b, and a controller 15.

[0026] The display panel 11 may include a plurality of pixels P arranged in a matrix form. Each pixel P may include an organic light emitting diode (OLED) and a pixel circuit that supplies a driving current to the OLED. The pixel circuit may receive a data signal corresponding to a gate signal, generate a driving current, and supply the generated driving current to the OLED. In addition, the display panel 11 may be driven by a range of voltages. The range of voltages applied to the display panel 11 may include a first voltage EVDD and a second voltage EVSS having a level lower than the first voltage EVDD. The display panel 11 may be driven by the first voltage EVDD and the second voltage EVSS. The first voltage EVDD may be provided for each pixel column, and the second voltage EVSS may be a common voltage commonly provided to the plurality of pixels P.

[0027] The touch sensing unit 12 may be disposed above the display panel 11 and may detect a touch from a finger or a stylus. In this case, the touch includes not only a direct touch but also an approach at a specific interval.

[0028] The display driver 14a may transmit a gate signal and a data signal to the display panel 11. The display driver 14a may receive an image signal and then generate a data signal. In this case, a single display driver 14a is shown, but the present invention is not limited thereto. The number of display drivers may be determined according to the size or resolution of the display panel 11. The display driver 14a may be implemented as an integrated circuit.

[0029] The touch driver 14b may transmit a touch driving signal to the touch sensing unit 12 and may receive a touch sensing signal in response to the touch driving signal. The touch driver 14b may be implemented as an integrated circuit.

[0030] The controller 15 may separately control the display driver 14a and the touch driver 14b. In addition, the controller 15 may provide an image signal to the display driver 14a.

[0031] Figure 2 is a circuit diagram of a pixel according to some embodiments of the present invention.

[0032] Referring to Figure 2 , the pixel P may include a pixel circuit including an organic light emitting diode OLED, first to third transistors T1 to T3, and a capacitor C1. In this case, the first transistor T1 may be a driving transistor that supplies a driving current to the organic light emitting diode OLED.

[0033] The first transistor T1 may have: a first electrode connected to a first voltage line VL1 to which a first voltage EVDD is applied, a second electrode connected to a second node N2, and a gate electrode connected to a first node N1. The second transistor T2 may have: a first electrode connected to a data line DL to which a data voltage Vdata is applied, a second electrode connected to the first node N1, and a gate electrode connected to a gate line GL to which a gate signal gate is applied. The third transistor T3 may have a first electrode connected to the second node N2, a second electrode connected to a second voltage line VL2, and a third electrode connected to a sense control signal line SEL to which a sense control signal Sense is applied. In this case, the sense control signal line SEL may be the gate line GL. The organic light emitting diode OLED may have an anode electrode connected to the second node N2 and a cathode electrode to which a second voltage EVSS is applied. The cathode electrode may be connected to the second voltage line. Accordingly, a driving current provided by the first transistor T1 may flow through the organic light emitting diode OLED. In addition, a capacitor C1 may be connected between the first node N1 and the second node N2, and thus the voltage applied to the first node N1 may be maintained. The first voltage EVDD may be applied to the first voltage line VL1, and a first reference voltage Vref may be applied to the second voltage line VL2.

[0034] Figure 3 is a plan view illustrating a touch sensing unit according to some embodiments of the present invention.

[0035] Referring to Figure 3 , the touch sensing unit is disposed on the display panel 11, and the touch sensing unit may include a plurality of first touch electrodes TEa and a plurality of second touch electrodes TEb. The plurality of first touch electrodes TEa may correspond to one or more touch driving electrodes TEa, and the plurality of second touch electrodes TEb may correspond to one or more touch sensing electrodes TEb. The plurality of first touch electrodes TEa may be connected to each other through a bridging part 322 in a row direction and form a plurality of electrode rows. The plurality of second touch electrodes TEb may be connected to each other through the bridging part 322 in a column direction and form a plurality of electrode columns. In this case, the plurality of first touch electrodes TEa and the plurality of second touch electrodes TEb may be arranged in a 4×3 matrix, but the present invention is not limited thereto. As Figure 9 shown, the touch insulating film 122 may include touch contact holes, and the second touch electrodes 123 may contact the bridging part 322 on the touch buffer layer 119 through the touch contact holes. The touch buffer layer 119 and the touch insulating film 122 may extend to the pad area 200.

[0036] One or more touch driving signals may be applied to the first touch electrode TEa, and one or more touch sensing signals corresponding to the touch driving signals may be applied to the second touch electrode TEb. The first touch electrode TEa and the second touch electrode TEb may be disposed in the same layer above the display panel 11, but the present invention is not limited thereto.

[0037] The bridging portion 322 may connect the first touch electrode TEa to one or more other first touch electrodes. The bridging portion 322 may also connect the second touch electrode TEb to one or more other second touch electrodes. To prevent a direct connection between the first touch electrode TEa and the second touch electrode TEb due to the bridging portions crossing each other, the bridging portion 322 connecting the first touch electrode TEa may be disposed in a layer different from the first touch electrode TEa and the second touch electrode TEb, and the bridging portion 322 may be connected to the first touch electrode TEa through one or more vias. The bridging portion 322 connecting the second touch electrode TEb may be disposed in the same layer as the one or more first touch electrodes TEa and the one or more second touch electrodes TEb, and may be connected to the second touch electrode TEb in the same layer. Accordingly, an insulating film may be disposed between the bridging portion 322 connecting the first touch electrode TEa and the bridging portion 322 connecting the second touch electrode TEb.

[0038] In addition, the first touch electrode TEa and the second touch electrode TEb may be formed by patterning a conductive metal layer. In addition, the first touch electrode TEa and the second touch electrode TEb may be formed of a transparent material such as indium tin oxide (ITO). In addition, the patterned first touch electrode TEa and second touch electrode TEb and the bridging portion 322 may have an electrode pattern formed in a mesh shape, and the first touch electrode TEa and the second touch electrode TEb may have a plurality of openings. Since the first touch electrode TEa and the second touch electrode TEb are formed of ITO electrodes or have openings, light emitted from the display device may be transmitted through the first touch electrode TEa and the second touch electrode TEb or emitted to the outside through the plurality of openings.

[0039] The patterns of the first touch electrode TEa and the second touch electrode TEb and the bridging portion 322 formed in a mesh shape may be referred to as touch electrode wirings. The first touch electrode TEa and the second touch electrode TEb may be connected to touch driving lines 321a, 321b and a touch sensing line 321c. The touch driving lines 321a, 321b can apply driving signals to the touch electrodes, and the touch sensing line 321c transmits sensing signals generated in response to touch events detected through the touch electrodes. One or both of the touch driving lines 321a, 321b and the touch sensing line 321c may be disposed on a side surface of the encapsulation layer. One or both of the touch driving lines 321a, 321b and the touch sensing line 321c may be disposed on a side surface of the touch buffer layer 119 or the touch insulating film 122.

[0040] Figure 4 It is a plan view illustrating a touch sensing unit according to some embodiments of the present invention.

[0041] Referring to Figure 4 , the touch sensing unit is disposed on the display panel, and a plurality of touch electrodes TE having a predetermined area may be arranged in a matrix form on the display panel 11. In addition, a plurality of touch lines 420 may be connected to each touch electrode TE to receive a touch sensing signal therefrom. The touch lines 420 may be disposed in the lower portion of the touch electrodes and may contact the areas of the touch electrodes TE. Since the touch electrodes TE and the touch lines 420 may be arranged inside the display panel 11, the display device may be provided in such a way that a separate touch panel is not included on the display panel 11, and thus a thinner display panel 11 may be provided.

[0042] Figures 5 to 9 It is a cross-sectional view illustrating a manufacturing process according to some embodiments of the present invention.

[0043] Referring to Figure 5 , the substrate 110 has a display area 100 and a pad area 200, and a thin film transistor, a gate line for applying a gate signal to the thin film transistor, and a data line for applying a data signal to the thin film transistor may be formed above the display area 100. The substrate 110 may include polyimide, but the present invention is not limited thereto. In addition, when the data line is formed on the substrate 110, the source electrode and the drain electrode 111b of the thin film transistor and the signal line 111a extending from the pad area 200 toward the display area 100 may be formed simultaneously. The signal line 111a may extend from the display area 100 to the pad area 200. The pad area 200 includes a touch pad 101. The signal line 111a is exposed in the pad area 200 and thus may serve as a pad for connection to an external device. However, the present invention is not limited thereto. In addition, the external device connected to the touch pad 101 may be a data driver, a gate driver, etc. In addition, the external device may be a printed circuit board PCB on which a data driver and a gate driver may be mounted. However, the present invention is not limited thereto.

[0044] A planarization film 112 may be provided on the drain electrode 111b. Then, the planarization film 112 is patterned, and the anode electrode 113 and the drain electrode 111b may be formed to be connected to each other. A bank portion 114b may be formed on the anode electrode 113, and an organic light-emitting film 114a may be formed in a cavity formed in the bank portion 114b. A cathode electrode 115 may be formed on the bank portion 114b in which the organic light-emitting film 114a is formed. The bank portion 114b in which the organic light-emitting film 114a is formed may be referred to as a light-emitting layer. The cathode electrode 115 may be a common electrode. A first inorganic film 116 may be formed on the cathode electrode 115. When forming the first inorganic film 116, a dam 112a may be formed above a portion where the pad region 200 and the display region 100 are adjacent to each other. The dam 112a may be formed when forming the planarization film 112. The dam 112a may have a dual structure such as being composed of two layers or two peaks. In addition, when forming the first inorganic film 116, the first inorganic film 116 may not be formed to cover the pad region 200, and the film may be formed by any patterning technique using a mask. The first inorganic film 116 may cover the upper portion of the dam 112a. However, the present invention is not limited thereto. In addition, the display region 100 and the pad region 200 may be defined on the substrate 110 with respect to the dam 112a. However, the present invention is not limited thereto, and the pad region 200 may be an area where the signal line 111a provided on the substrate is exposed or an area where a conductor provided on the signal line 111a is exposed. The conductor provided on the signal line 111a may be Figure 9 the second touch electrode 123 shown in

[0045] Refer to Figure 6 , and a first organic film 117 is formed on the first inorganic film 116. In order to protect the organic light-emitting film 114a, a thicker layer may be provided on the organic light-emitting film 114a to prevent foreign substances such as moisture from penetrating into the organic light-emitting film 114a. However, there are some limitations to increasing the thickness of the first inorganic film 116. Therefore, in order to protect the organic light-emitting film 114a, a first organic film 117 with an increased thickness may be provided on the first inorganic film 116. The dam 112a is used to prevent the first organic film 117 from penetrating into the pad region 200.

[0046] Refer to Figure 7 , and a second inorganic film 118 may be formed on the first organic film 117. The second inorganic film 118 may cover the upper portion of the dam 112a formed through the first inorganic film 116. When forming the first inorganic film 116, it is patterned using a mask, but the second inorganic film 118 may be formed without using a mask. The deposited first inorganic film 116, the first organic film 117, and the second inorganic film 118 may be referred to as an encapsulation layer.

[0047] Refer to Figure 8, a touch buffer layer 119 can be formed on the second inorganic film 118. The touch sensing unit can be mounted on the encapsulation layer through patterning of the touch electrodes, and the encapsulation layer may be damaged when the touch electrodes are formed. To solve this problem, the touch buffer layer 119 can be formed on the encapsulation layer. The touch buffer layer 119 can be formed without using a mask. The touch buffer layer 119 can be formed using an inorganic film. The touch buffer layer 119 is used to prevent the substrate from being damaged, but is not limited to preventing the formation of defects when forming the touch electrodes.

[0048] Referring to Figure 9 , the first touch electrode 121 and the second touch electrode 123 can be formed on the touch buffer layer 119. The first touch electrode 121 can be the bridging portion 322, as Figure 3 shown; and the second touch electrode 123 can be a plurality of first touch electrodes TEa and / or a plurality of second touch electrodes TEb, as Figure 3 shown. The bridging portion 322 can be disposed on a layer different from the plurality of first touch electrodes TEa and the plurality of second touch electrodes TEb. A touch insulating film 122 can be disposed between the first touch electrode 121 and the second touch electrode 123. A protective layer 124 can be formed on the second touch electrode 123. The first touch electrode 121 can be the Figure 4 touch electrode TE shown, and the second touch electrode 123 can be the Figure 4 touch line 420 shown.

[0049] First, a first touch electrode 121 may be formed on the touch buffer layer 119. When forming the first touch electrode 121, the first touch electrode 121 may be patterned using a mask, or when forming the first touch electrode 121, the touch buffer layer 119 and the second inorganic film 118 disposed under the first touch electrode 121 may be patterned. Accordingly, when forming the first touch electrode 121, the touch buffer layer 119 and the second inorganic film 118 are patterned; since a separate patterning is not required, one mask may be used. At this time, in a case where the first inorganic film 116 was not patterned in a previous process, the first inorganic film 116 may also be patterned when forming the first touch electrode 121. Accordingly, the manufacturing process of the display device 1 may be simplified and the cost may be reduced. At this time, the second inorganic film 118 and the touch buffer layer 119 formed in the pad region 200 are removed, and as a result, signal lines may be exposed. In addition, since the second inorganic film 118 and the touch buffer layer 119 may be patterned using a single mask, a margin in the mask process may be set to be smaller. That is, when performing two mask processes, a margin for each mask process needs to be set, but when performing a single mask process, only a margin for the single mask process needs to be set, whereby a margin smaller than that when performing the two mask processes may be set. As a result, the area of the display region on the substrate 110 may be increased and the area of the pad region may be reduced. Accordingly, the bezel region may be designed to be smaller.

[0050] After patterning the first touch electrode 121, a touch insulating film 122 is deposited, and after depositing the touch insulating film 122, a second touch electrode 123 may be formed on the touch insulating film 122 by patterning. At this time, the second touch electrode 123 may be formed on the signal line 111a exposed in the pad region. In addition, the signal line 111a may be in contact with the second touch electrode 123. As a result, a signal may be transmitted to the second touch electrode 123 through the signal line 111a. Since a protective layer 124 is provided on the second touch electrode 123, the second touch electrode 123 may be protected. The protective layer 124 may be an organic film or an inorganic film. One or both of the touch driving lines 321a, 321b and the touch sensing line 321c may be disposed on a side surface of the encapsulation layer. One or both of the touch driving lines 321a, 321b and the touch sensing line 321c may be disposed on a side surface of the touch buffer layer 199 or the touch insulating film 122. The touch pad 101 may include an upper pad electrode and a lower pad electrode. The signal line 111a may be the lower pad electrode. The second touch electrode 123 may be the upper pad electrode. The lower pad electrode / signal line 111a may be the same material as the source electrode and the drain electrode 111b. The upper pad electrode may be made of the same material as the touch driving line 321a or the touch sensing line 321c.

[0051] Figures 10 to 14It is a cross-sectional view illustrating a manufacturing process of a pad region and a display region adjacent to the pad region in a display device according to some embodiments of the present invention.

[0052] Referring to Figure 10 , a first inorganic film 116 may be formed on a substrate having a display region 100 and a pad region 200. A first organic film 117 may be disposed on the first inorganic film 116. The first organic film 117 may be disposed only on the display region 100. A second inorganic film 118 may be formed on the first organic film 117. At this time, since no mask is used, the second inorganic film 118 is not patterned, and thus the second inorganic film 118 may be formed on both the display region 100 and the pad region 200. A touch buffer layer 119 may be formed on the second inorganic film 118.

[0053] Referring to Figure 11 , after forming the touch buffer layer 119, a first touch electrode 121 may be formed on the touch buffer layer 119. The first touch electrode 121 may be formed using a mask.

[0054] Referring to Figure 12 , after forming the first touch electrode 121, a touch insulating film 122 may be formed on the first touch electrode 121. The touch insulating film 122 located on the pad region 200 may be etched. The touch insulating film 122 may be an inorganic film; when etching the touch insulating film 122, since the first inorganic film 116 and the second inorganic film 118 located under the touch insulating film 122 may be etched together, the pad region 200 may be exposed. The exposure of the pad region 200 may expose the signal lines located in the pad region 200.

[0055] However, even when etching the touch insulating film 122, at least a part of the first inorganic film 116 and / or the second inorganic film 118 may remain in the pad region 200, as shown in Figure 13 . Therefore, as shown in Figure 14 , when performing patterning to form a second touch electrode 123 on the touch insulating film 122, the first inorganic film 116 and / or the second inorganic film 118 remaining in the pad region 200 may be removed. Thus, the signal lines may be exposed in the pad region 200. A protective layer 124 may be further formed on the second touch electrode 123. The first inorganic film 116, the second inorganic film 118, and the touch buffer layer 119 may be sequentially deposited above the outer edge of the region in the pad region 200 having the exposed signal lines.

[0056] Figure 15 It is a flowchart illustrating a method of manufacturing a display device according to some embodiments of the present invention.

[0057] Referring to Figure 15, according to the method of manufacturing a display device, a display area and a pad area can be formed on a substrate. A thin film transistor can be formed on the substrate; a light emitting layer including an organic light emitting film, the organic light emitting film contacting at least a part of the thin film transistor; and a cathode electrode formed on the light emitting layer (step S1500). One or more pixels including the thin film transistor and one or more signal lines can be formed in the display area and the pad area respectively. In addition, a dam portion can be formed in the display area adjacent to the pad area. The dam portion can have a dual structure such as being composed of two layers or two peaks. The dam portion can be formed using a planarization film provided under the light emitting layer. However, the present invention is not limited thereto.

[0058] A first inorganic film can be provided on the cathode electrode and then patterned (step S1510). The first inorganic film can be deposited on the dam portion.

[0059] A first organic film can be provided on the first inorganic film (step S1520). The thickness of the first organic film can be above a predetermined value, thereby preventing foreign substances from infiltrating into the light emitting layer. In addition, the dam portion is used to prevent the first organic film from infiltrating into the pad area. The dam portion serves as a reference for defining the display area and the pad area. However, the present invention is not limited thereto, and the pad area 200 can be an area where the signal line 111a provided on the substrate is exposed or an area where a conductor provided on the signal line 111a is exposed. The conductor provided on the signal line 111a can be the second touch electrode 123 described below.

[0060] A second inorganic film can be provided on the first organic film (step S1530). Since the second inorganic film is not patterned, it can be provided on the first organic film without using a mask. Therefore, the process for patterning the second inorganic film can be omitted. The first inorganic film, the first organic film, and the second inorganic film can be referred to as an encapsulation layer.

[0061] A touch buffer layer can be formed on the second inorganic film (step S1540). The first inorganic film, the first organic film, and the second inorganic film can be damaged by heat; in the case where a touch sensing unit including a touch electrode is provided on the second inorganic film, a process for patterning the touch electrode etc. may be required. The first inorganic film, the first organic film, and the second inorganic film can be damaged by the process for patterning the touch electrode. To solve this problem, the formation of the touch buffer layer can be used to prevent the first inorganic film, the first organic film, and the second inorganic film formed in the early process from being damaged.

[0062] Touch electrodes on the patternable touch buffer layer (step S1550). The touch buffer layer and the second inorganic film can be patterned when forming the touch electrodes. Thus, when removing the touch buffer layer and the second inorganic film in the pad area by etching the touch buffer layer and the second inorganic film using a single mask, the number of mask processes required can be reduced. If the number of mask processes is reduced to one, the process margin can be set smaller when performing one mask process compared to when performing two mask processes, and thus the size of the pad area on the substrate can be reduced. In the case where the first inorganic film is disposed in the pad area without being patterned, in step S1550, the first inorganic film can be etched together with the touch buffer layer and the second inorganic film when etching the touch buffer layer and the second inorganic film.

[0063] In addition, when patterning the first touch electrode among at least two touch electrodes, the patterning of the touch electrodes can pattern and remove the touch buffer layer and the second inorganic film in the pad area. In addition, when removing the touch insulating film in the pad area by etching, the patterning of the touch electrodes can pattern and remove the touch buffer layer and the second inorganic film. In addition, when patterning the second touch electrode on the touch insulating film, the patterning of the touch electrodes can pattern and remove the touch buffer layer and the second inorganic film in the pad area.

[0064] The features, structures, configurations, and effects described in the present invention are included in at least one embodiment, but are not necessarily limited to the specific embodiments. Those skilled in the art can apply the features, structures, configurations, and effects shown in the specific embodiments to another or more other embodiments by combining or modifying these features, structures, configurations, and effects. It should be understood that all such combinations and modifications are included within the scope of the present invention. Although the exemplary embodiments have been described for illustrative purposes, those skilled in the art will understand that various modifications and applications are possible without departing from the essential characteristics of the present invention. For example, the specific components of the exemplary embodiments can be variously modified. The above-described embodiments can be combined to provide further embodiments. These and other variations can be made to the embodiments in accordance with the above detailed description. Generally speaking, in the following claims, the terms used should not be construed as limiting the claims to the specific embodiments disclosed in the specification and the claims, but should be construed as including all possible embodiments consistent with the entire equivalent scope claimed by these claims. Therefore, the claims are not limited by the specific embodiments.

[0065] According to one or more exemplary embodiments of the present invention, a display device is provided, including: a substrate having a display area and a pad area for applying signals to the display area; an encapsulation layer disposed in the display area and including a first inorganic film, a second inorganic film disposed on the first inorganic film, and a first organic film disposed between the first inorganic film and the second inorganic film; a touch buffer layer disposed on the encapsulation layer; and a touch sensing unit disposed on the touch buffer layer, wherein at least one of the first inorganic film and the second inorganic film is disposed in a part of the pad area and the touch buffer layer is disposed on the at least one inorganic film.

[0066] According to one or more exemplary embodiments of the present invention, the display device further includes a dam portion disposed between the display area and the pad area, wherein at least one of the first inorganic film and the second inorganic film is disposed on the dam portion.

[0067] According to one or more exemplary embodiments of the present invention, the display device further includes a first touch electrode disposed on the touch buffer layer and patterned, a touch insulating film disposed on the first touch electrode, and a second touch electrode disposed on the touch insulating film and patterned.

[0068] According to one or more exemplary embodiments of the present invention, the display device further includes a protective layer disposed on the second touch electrode, wherein the second touch electrode extends to the pad area and is exposed in the pad area.

[0069] According to one or more exemplary embodiments of the present invention, a method of manufacturing a display device is provided, including: disposing a first inorganic film on a substrate; disposing a first organic film on the first inorganic film; disposing a second inorganic film on the first organic film; forming a touch buffer layer on the second inorganic film; and patterning a touch electrode on the touch buffer layer, wherein when patterning the touch electrode, at least one of the first inorganic film and the second inorganic film and the touch buffer layer are patterned.

[0070] According to one or more exemplary embodiments of the present invention, the patterning of the touch electrode includes: patterning of the first touch electrode, patterning of the touch insulating film on the first touch electrode, and patterning of the second touch electrode on the touch insulating film.

[0071] According to one or more exemplary embodiments of the present invention, when patterning the touch insulating film, at least one of the first inorganic film and the second inorganic film and the touch buffer layer are patterned.

[0072] According to one or more exemplary embodiments of the present invention, the substrate has a display area and a pad area, and further includes depositing in the display area: a thin film transistor disposed on the substrate; a light emitting layer including an organic light emitting film, the organic light emitting film contacting at least a part of the thin film transistor; and a cathode electrode disposed on the light emitting layer.

[0073] According to one or more exemplary embodiments of the present invention, the method further includes forming a signal line and a pad contacting the touch electrode in the pad area.

Claims

1. A display device, comprising: a substrate having a display area and a pad area; a thin film transistor on the substrate, including a source electrode and a drain electrode; a light-emitting film layer, including an anode electrode connected to the drain electrode, an organic light-emitting film on the anode electrode, and a cathode electrode on the organic light-emitting film; a packaging layer, including a first inorganic film, a first organic film on the first inorganic film, and a second inorganic film on the first organic film; a touch buffer layer on the second inorganic film of the packaging layer; a first touch electrode and a second touch electrode on the touch buffer layer; a touch insulating film disposed between the first touch electrode and the second touch electrode; a touch pad in the pad area; a touch line electrically connecting the second touch electrode to the touch pad, the touch line being disposed on a side surface of the packaging layer; and a dam portion disposed between the display area and the pad area, wherein the touch insulating film extends to the pad area such that the touch insulating film extends along an inclined side surface of the packaging layer, extends over a side surface and an upper surface of the dam portion while being located between the touch line and the touch buffer layer, and contacts the touch pad.

2. The display device according to claim 1, wherein the second touch electrode includes a touch driving electrode and a touch sensing electrode.

3. The display device according to claim 2, wherein the touch line includes a touch sensing line connected to the touch sensing electrode.

4. The display device according to claim 2, wherein the touch line includes a touch driving line connected to the touch driving electrode.

5. The display device according to claim 1, wherein the touch pad includes a lower pad electrode and an upper pad electrode disposed on the lower pad electrode, wherein the touch line is integrally formed with the upper pad electrode of the touch pad.

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