Display device and method of manufacturing the same

Abstract

A display device and a manufacturing method thereof are disclosed. The display device includes a display panel and a flexible circuit board, the display panel includes a first substrate having a thin film transistor, a second substrate facing the first substrate, and a wiring layer arranged on the first substrate, and the flexible circuit board is arranged on a first side of the display panel, wherein the first side of the display panel includes a recessed portion, the wiring layer is exposed in the recessed portion on the first side, the flexible circuit board includes a conductive pad, and the conductive pad contacts the wiring layer in the recessed portion to electrically connect the flexible circuit board to the wiring layer. The recessed portion includes a first recessed portion arranged on the first substrate.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2019-0019063, filed on February 19, 2019, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The inventive concept relates to a display device, and more particularly, to a display device including a conductive pad on a side of the display device and a method of manufacturing the same. Background Art

[0004] Various display devices such as a liquid crystal display (LCD) or an organic light emitting diode display (OLED) include a display panel on which a plurality of pixels for displaying an image are formed and a driving circuit for driving the display panel.

[0005] The display panel includes a display area in which a plurality of pixels are formed. A frame area as a peripheral area where no image is displayed may be arranged near the display area. Various types of driving circuits and wirings may be arranged in the frame area.

[0006] Recently, in order to reduce a bezel area as a non-display area, research and development on a technology of bonding an integrated circuit (IC), other types of printed circuits, and wirings to the side of a display panel is underway.

[0007] The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art. Summary of the invention

[0008] The present inventive concept has been devoted to providing a display device and a manufacturing method thereof that prevents short circuit of wiring and improves defects by forming a recess on a side of a display panel and increasing a contact area between a wiring exposed on the side of the display panel and a conductive pad, and improves efficiency by reducing contact resistance.

[0009] An exemplary embodiment of the present inventive concept provides a display device, which includes a display panel and a flexible circuit board, the display panel including a first substrate having a thin film transistor, a second substrate facing the first substrate, and a wiring layer arranged on the first substrate, and the flexible circuit board is arranged on a first side of the display panel, wherein the first side of the display panel includes a recess, the wiring layer is exposed in the recess on the first side, the flexible circuit board includes a conductive pad, and the conductive pad contacts the wiring layer in the recess to electrically connect the flexible circuit board with the wiring layer, wherein the recess includes a first recess arranged on the first substrate.

[0010] The recessed portion may further include a second recessed portion disposed on the second substrate and a third recessed portion disposed on the wiring layer.

[0011] The first recess, the second recess, and the third recess may be recessed from the first side to a first depth, and the first depth may be 0.5 μm to 10 μm.

[0012] The display device may further include a conductive filler disposed between the conductive pad and the wiring layer to fill the concave portion.

[0013] The recess may include a plurality of recesses, at least two recesses among the plurality of recesses having different widths.

[0014] The wiring layer may include a first wiring layer and a second wiring layer electrically connected to each other, the first wiring layer may include the same material as the gate electrode of the thin film transistor and be formed simultaneously with the gate electrode of the thin film transistor, and the second wiring layer may include the same material as the data line of the thin film transistor and be formed simultaneously with the data line of the thin film transistor.

[0015] The height of the recess may be greater than the thickness of the wiring layer, and the conductive pad may completely fill the recess.

[0016] The display device may further include a dummy pattern and a columnar spacer, the dummy pattern being arranged on the wiring layer to overlap the wiring layer and directly contacting the conductive pad, and the columnar spacer being arranged on the dummy pattern to overlap the dummy pattern and directly contacting the conductive pad.

[0017] Another embodiment of the present inventive concept provides a display device, which includes a display panel and a flexible circuit board, the display panel including a first substrate having a thin film transistor, a second substrate facing the first substrate, and a wiring layer arranged on the first substrate, and the flexible circuit board is arranged on a first side of the display panel, wherein the first side of the display panel includes a recess, the wiring layer is exposed in the recess on the first side, the flexible circuit board includes a conductive pad, and the conductive pad contacts the wiring layer in the recess to electrically connect the flexible circuit board with the wiring layer, wherein the height of the recess is equal to the thickness of the wiring layer.

[0018] The display device may further include a dummy pattern and a columnar spacer, the dummy pattern being arranged on the wiring layer to overlap the wiring layer and directly contacting the conductive pad, and the columnar spacer being arranged on the dummy pattern to overlap the dummy pattern and directly contacting the conductive pad.

[0019] The recess may be recessed from the first side surface to a first depth, and wherein the first depth is 0.5 μm to 10 μm.

[0020] The display device may further include a conductive filler disposed between the conductive pad and the wiring layer to fill the concave portion.

[0021] The recess may include a plurality of recesses, at least two recesses among the plurality of recesses having different widths.

[0022] The wiring layer may include a first wiring layer and a second wiring layer electrically connected to each other, the first wiring layer including the same material as the gate electrode of the thin film transistor and formed simultaneously with the gate electrode of the thin film transistor, and the second wiring layer including the same material as the data line of the thin film transistor and formed simultaneously with the data line of the thin film transistor.

[0023] The conductive pad may completely fill the recess.

[0024] Another embodiment of the present inventive concept provides a method for manufacturing a display device, the method comprising: cleaning a first side of a display panel to which a first display panel and a second display panel facing the first display panel are bonded; heating the first side of the display panel with a first laser; after heating the first side of the display panel with the first laser, coating a conductive adhesive on the first side of the display panel; hardening the conductive adhesive with a second laser; and after curing the conductive adhesive, patterning the conductive adhesive with a laser beam to form a conductive pad, wherein the first display panel includes a wiring layer, and the wiring layer is exposed on the first side of the display panel.

[0025] When heating the first side of the display panel with the first laser, the first laser may generate a pulsed first laser beam having a first energy, and the first laser beam may be repeatedly applied to the first side of the display panel.

[0026] During heating of the first side of the display panel with the first laser beam, organic residues on the first side of the display panel may be removed, and a concave portion may be formed.

[0027] The laser beam used to form the conductive pad may have a second energy greater than the first energy.

[0028] The method may further include, after forming the conductive pad, attaching a flexible circuit board including a data driver to the conductive pad.

[0029] According to exemplary embodiments, short circuits of wirings are prevented and defects are reduced by forming recesses on the sides of the display panel and increasing a contact area between wirings exposed on the sides of the display panel and a conductive pad, and efficiency is improved by reducing contact resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A perspective view showing a display device according to an exemplary embodiment is shown.

[0031] Figure 2 and Figure 3 Shows Figure 1Perspective view of a part of.

[0032] Figure 4 Shown in detail Figure 2 part of.

[0033] Figure 5 , Figure 6 , Figure 7 and Figure 8 According to another exemplary embodiment, Figure 1 A cross-sectional view of the display device taken along line V-V'.

[0034] Fig. 9 A block diagram illustrating a method for manufacturing a display device according to an exemplary embodiment is shown.

[0035] Fig.10 , Fig.11 , Fig.12 and Fig.13 An exemplary embodiment is shown Fig. 9 A perspective view of the display device at the corresponding stage is shown in FIG. DETAILED DESCRIPTION

[0036] Hereinafter, the inventive concept will be described more fully with reference to the accompanying drawings showing exemplary embodiments of the inventive concept. It will be appreciated by those skilled in the art that the described embodiments may be modified in various different ways without departing from the spirit or scope of the inventive concept.

[0037] The drawings and description are to be regarded as illustrative in nature and not restrictive, and like reference numerals refer to like elements throughout the specification.

[0038] For better understanding and ease of description, the size and thickness of each configuration shown in the drawings are arbitrarily shown, and the inventive concept is not limited thereto. For clarity, the thickness of layers, films, panels, regions, etc. are exaggerated. For better understanding and ease of description, the thickness of some layers and regions is magnified.

[0039] It should be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, the element may be directly on the other element, or there may be intervening elements. Conversely, when an element is referred to as being "directly on" another element, there are no intervening elements. The term "on" or "above" means being positioned above or below an object portion, and does not necessarily mean being positioned on the upper side of an object portion based on the direction of gravity.

[0040] Unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising” will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.

[0041] The phrase "on a plane" means observing the object portion from the top, and the phrase "on a cross section" means observing a vertically cut cross section of the object portion from the side.

[0042] Now refer to Figure 1 A display device according to an exemplary embodiment is described. Figure 1 A perspective view showing a display device according to an exemplary embodiment is shown.

[0043] Reference Figure 1 , a display device 1000 according to an exemplary embodiment includes a display panel 10 , a flexible circuit board 500 attached to a first side S1 of the display panel 10 , and a driving circuit substrate 600 .

[0044] The display panel 10 includes a first display panel 100 and a second display panel 200 coupled to each other, and although not shown, it may further include a backlight unit on the bottom of the first display panel 100 of the display panel 10 .

[0045] The display device 1000 may be a device in which a liquid crystal layer 300 is disposed between a first display panel 100 and a second display panel 200 (see Figure 5 The display device 1000 may be a liquid crystal display (LCD) having an organic light emitting element disposed between the first display panel 100 and the second display panel 200 instead of the liquid crystal layer 300 (see Figure 5 ) of an organic light emitting diode display (OLED). In this case, at least one of the first display panel 100 and the second display panel 200 may include a touch electrode for sensing a touch provided from the outside. According to an exemplary embodiment, the display device 1000 may further include a color conversion layer disposed between the first display panel 100 and the second display panel 200. The color conversion layer may include quantum dots and / or color filters CF (see FIG. 1 ) disposed in a liquid crystal display (LCD) and an organic light emitting diode display (OLED). Figures 5 to 8 ). The liquid crystal display (LCD) may further include a backlight unit for emitting blue light. The organic light emitting element in the organic light emitting diode display (OLED) may emit blue light. The display device 1000 is not limited to the above examples.

[0046] In the display panel 10, the first display panel 100 may include a transistor TR to be described (see Figures 5 to 8), and the second display panel 200 may be a color conversion substrate including a color conversion layer (e.g., a color filter CF and / or quantum dots). However, depending on the exemplary embodiment, the transistor TR and the color conversion layer may be provided on the same substrate, which is referred to as a color filter on an array (COA) structure, and the positions of the transistor TR and the color filter CF are not limited to those disclosed in the exemplary embodiment.

[0047] The first display panel 100 and the second display panel 200 of the display panel 10 may respectively have a rectangular shape having a long side extending in a first direction DR1 and a short side extending in a second direction DR2 crossing the first direction DR1. According to an exemplary embodiment, predetermined areas of the first display panel 100 and the second display panel 200 may have a curved line. The display panel 10 may include a first side surface S1 disposed along the long side and a second side surface S2 disposed along the short side. The display panel 10 may include a first side surface S1, a second side surface S2, a third side surface (not shown) facing the first side surface S1, and a fourth side surface (not shown) facing the second side surface S2.

[0048] The first display panel 100 includes a first substrate 110 and a plurality of thin film layers arranged thereon. A wiring layer 180 is provided on the first substrate 110, and the wiring layer 180 includes a first wiring layer 120 and a second wiring layer 170. For the convenience of description, the first wiring layer 120 and the second wiring layer 170 are respectively shown as single layers, and the first wiring layer 120 and the second wiring layer 170 may be etched and arranged with appropriate patterns for configuring various signal lines, transistors TR and light emitting devices. Hereinafter, different portions of the wiring layer 180 arranged on each of the corresponding conductive pads 400 may not be electrically connected to each other.

[0049] For example, the first wiring layer 120 and the second wiring layer 170 may include constituent elements of the transistor TR and a portion in contact with the conductive pad 400. The first wiring layer 120 may include the same material as the gate electrode and the gate line GL for transmitting a gate signal to the pixel PX and may be formed simultaneously therewith. The second wiring layer 170 may include the same material as the data line DL for transmitting a data signal to the pixel PX and may be formed simultaneously therewith. In an exemplary embodiment, the wiring layer 180 includes the first wiring layer 120 and the second wiring layer 170, however, the wiring layer 180 may be a single conductive layer or a wiring layer having more than three wiring layers.

[0050] The flexible circuit board 500 is attached to the first side S1 of the display panel 10. The flexible circuit board 500 includes a conductive pad 400. The flexible circuit board 500 may be connected to a signal line on the display panel 10 through the conductive pad 400. The signal line on the display panel 10 may correspond to the wiring layer 180. The driving circuit substrate 600 may be bent at the bottom side of the first display panel 100 so that the driving circuit substrate 600 may be arranged on the bottom side of the first substrate 110.

[0051] Figure 1 The flexible circuit board 500 in the embodiment is arranged on the first side S1, but it may be arranged on the second side S2, and it may be arranged on both the first side S1 and the second side S2. According to an exemplary embodiment, the flexible circuit board 500 may be respectively arranged on the first side S1 and the third side (not shown) facing the first side S1, and may be respectively arranged on the second side S2 and the fourth side (not shown) facing the second side S2. The position where the flexible circuit board 500 is to be connected to the display panel 10 through the conductive pad 400 is not limited thereto.

[0052] like Figure 1 As shown by the dotted line in FIG. 1 , the flexible circuit board 500 is attached to the first side S1 of the display panel 10, and the conductive pad 400 is disposed between the flexible circuit board 500 and the first side S1 of the display panel 10. Figure 3 A detailed structure in which the conductive pad 400 is attached to the first side surface S1 of the display panel 10 is further described.

[0053] The conductive pads 400 may be provided with a conductive adhesive film 440 (see Figure 5 ) is electrically connected to the flexible circuit board 500. The conductive adhesive film 440 may be omitted, and the conductive pad 400 may be directly formed on the flexible circuit board 500. As described above, the data driver DD including at least one driving chip 510 may be provided on the flexible circuit board 500.

[0054] The driving circuit substrate 600 may be electrically connected to one end of the flexible circuit board 500. In detail, corresponding access lines (not shown) may be electrically connected to each other through pads on each of the flexible circuit board 500 and the driving circuit substrate 600. Accordingly, electrical signals such as gate signals, data signals, and image data output by the driving circuit substrate 600 are transmitted to the flexible circuit board 500, and then may be transmitted to the wiring layer 180 of the display panel 10 through the conductive pads 400.

[0055] Regarding the display device 1000 according to the exemplary embodiment, on the first side surface ( Figure 1 A recess R is provided on the first side surface S1 in Figure 2 and Figure 4), so that the contact area between the wiring layer 180 on the display panel 10 and the conductive pad 400 on the flexible circuit board 500 attached to the first side S1 increases and the contact resistance decreases. Accordingly, the adhesion of the flexible circuit board 500 to the wiring layer 180 of the display panel 10 can be enhanced, and the open circuit of the wiring layers 180 adjacent to each other can be prevented, thereby preventing defects in the display device 1000. Figure 2 This is described in detail.

[0056] The main surfaces of the first and second display panels 100 and 200 are arranged parallel to each other. The main surfaces of the first and second display panels 100 and 200 are shown extending to a plane parallel to a plane formed by the first and second directions DR1 and DR2.

[0057] The first display panel 100 and the second display panel 200 may include glass having rigid properties, or may include a flexible substrate. When the first display panel 100 and the second display panel 200 are flexible, they may include a metal film or very thin glass, or various types of plastics such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), polyarylate (PAR), polyetherimide (PEI), polyethersulfone (PES), or polyimide (PI).

[0058] The display panel 10 includes a display area DA for displaying an image and a peripheral area NDA disposed around the display area DA and not displaying an image. The peripheral area NDA may be disposed to surround the display area DA.

[0059] A plurality of pixels PX and a plurality of signal lines are provided in the display area DA. The pixel PX represents a unit for emitting light of a predetermined color and includes at least one pixel electrode. The pixel PX may emit light having a brightness corresponding to the grayscale of an input image signal. In the present disclosure, the pixel PX may include a transistor TR and a light emitting device configured to emit light. The plurality of pixels PX may be arranged in a matrix form, and it is not limited thereto.

[0060] The plurality of signal lines include m data lines DL (e.g., DL1, ..., DLm) and n gate lines GL (e.g., GL1, ..., GLn). The data lines DL and the gate lines GL may be arranged to be insulated from each other and to cross each other. The gate lines GL may extend in a first direction DR1 and may be electrically connected to a gate driver GD. The data lines DL may extend in a second direction DR2 and may be electrically connected to a data driver DD. In more detail, the data lines DL may extend in a second direction DR2 on the display panel 10, may be bent along one side of the display panel 10 and may extend in a third direction DR3 along one side of the display panel 10, and may be electrically connected to the data driver DD.

[0061] Although the gate driver GD Figure 1 2 is shown as being disposed on the top side of the second display panel 200, but may also be disposed on the top side of the first display panel 100 facing the second display panel 200. The gate driver GD may be disposed along at least one short side of the first display panel 100. However, the position of the gate driver GD is not limited thereto.

[0062] The gate driver GD may include a plurality of driving chips each mounted on a flexible printed circuit board and connected to the first display panel 100 in a tape carrier package (TCP). According to an exemplary embodiment, the gate driver GD may be directly formed on the first substrate 110 simultaneously with the transistor TR for driving the pixel PX, and may include an amorphous silicon TFT gate driver circuit (ASG) or an oxide silicon TFT gate driver circuit (OSG).

[0063] The data driver DD may include at least one driving chip 510. Figure 1 Four driving chips 510 are shown, but the number of driving chips 510 is not limited thereto.

[0064] The driving circuit substrate 600 may include a timing controller (not shown). The timing controller may be an integrated circuit (IC) mounted on the driving circuit substrate 600, and may be electrically connected to the gate driver GD and the data driver DD. The timing controller (not shown) may output a gate control signal, a data control signal, and image data. According to an exemplary embodiment, the timing controller (not shown) and the data driver DD may be embedded in one chip, and the one chip may be arranged on the flexible circuit board 500.

[0065] The gate driver GD may receive a gate control signal from the timing controller. The gate driver GD may generate a gate signal in response to the gate control signal, and may sequentially output the gate signal to a plurality of gate lines GL. The gate signal may be provided to the pixel PX through the gate lines GL sequentially arranged along the first direction DR1. As a result, the pixel PX may be driven row by row.

[0066] The data driver DD may receive image data and a data control signal from the timing controller. The data driver DD may generate an analog data voltage corresponding to the image data in response to the data control signal and may output it to a plurality of data lines DL. The data voltage may be provided to the pixels PX through the plurality of data lines DL.

[0067] The pixel PX may receive a data voltage through the data line DL in response to a gate signal received through the gate line GL. The pixel PX displays a grayscale corresponding to the data voltage, thereby controlling the transmittance of a corresponding region where the corresponding pixel PX is disposed.

[0068] Now refer to Figure 2 and Figure 3 A side configuration of the display device 1000 according to an exemplary embodiment is described. Figure 2 and Figure 3 Shows Figure 1 A perspective view of a portion of the Figure 1 The first side surface S1 of the display panel 10 and the recess R on the conductive pad 400 are shown in FIG.

[0069] Reference Figure 2 , the display panel 10 includes a first display panel 100 and a second display panel 200 , the first display panel 100 includes a first substrate 110 and a wiring layer 180 , and the second display panel 200 faces the first display panel 100 .

[0070] The wiring layer 180 is disposed on the first substrate 110. As described above, the wiring layer 180 includes the first wiring layer 120 and the second wiring layer 170. Regarding the display device 1000 according to the exemplary embodiment, the first wiring layer 120 may include the gate line GL (see Figure 1 ), and the second wiring layer 170 may include a data line DL (see Figure 1 ).

[0071] A portion of the wiring layer 180 disposed between the first display panel 100 and the second display panel 200 on the first side S1 of the display panel 10 is exposed to the outside. As described, the flexible circuit board 500 may be attached to the first side S1 of the display panel 10 on which the wiring layer 180 is exposed. In this case, the flexible circuit board 500 and the driving circuit substrate 600 may be electrically connected to the wiring layer 180 of the display panel 10 through the conductive pads 400 disposed on the flexible circuit board 500.

[0072] A recess R is formed on the first side surface S1 of the display panel 10. The recess R may include a first recess R1 and a second recess R2. The recess R may include a plurality of first recesses R1 and a plurality of second recesses R2. The recess R may include only the first recess R1. The first recess R1 may be similar to the first recess R1. Figure 1 The portion corresponding to the data line DL shown in FIG. 1 may have a horizontal width smaller than a horizontal width of the second recess R2. The portion including at least one first recess R1 and at least one second recess R2 will be referred to as portion A and will be referred to as Figure 4 The recessed portion R will be described.

[0073] Reference Figure 3 , the conductive pad 400 is arranged on the recess R formed on the first side surface S1 of the display panel 10 . Figure 3The structure of the first side S1 of the display panel 10 is shown provided with the first substrate 110 as a part of the first display panel 100 and the first and second wiring layers 120 and 170 provided on the first substrate 110. The recess R may include a first recess R1 and a second recess R2. Figure 3 It is shown that the conductive pad 400 is arranged on a part of the recess R to illustrate the arrangement of the recess R and the conductive pad 400. However, the conductive pad 400 may be arranged on every recess R.

[0074] The conductive pad 400 includes a first pad 410 and a second pad 420. The first pad 410 is arranged on the first recess R1, and the second pad 420 is arranged on the second recess R2. The first pad 410 and the second pad 420 may be arranged to correspond to the shapes of the first recess R1 and the second recess R2. The first pad 410 may be arranged to completely fill the first recess R1, and the second pad 420 may be arranged to completely fill the second recess R2.

[0075] Now refer to Figure 4 A side structure of the display device 1000 according to an exemplary embodiment is described in detail. Figure 4 Shows Figure 2 Included in Figure 2 A portion A of a first recess R1 and a second recess R2.

[0076] Reference Figure 4 , a recess R is formed on the first side S1 of the display panel 10. The recess R includes a first recess R1 and a second recess R2. At least one first recess R1 and at least one second recess R2 may be formed on the first side S1 of the display panel 10. According to an exemplary embodiment, the recess R may be formed on both the first side S1 and the second side S2 disposed adjacent to the first side S1. The first recess R1 may be formed only on the first side S1.

[0077] The first recess R1 includes a first portion R1-1, a second portion R1-2, and a third portion R1-3. The first portion R1-1, the second portion R1-2, and the third portion R1-3 may form a C-shaped first recess R1. In detail, the first portion R1-1 may extend in parallel with the second side surface S2, the second portion R1-2 may extend in parallel with the first side surface S1 and be connected to the first portion R1-1, and the third portion R1-3 may extend in parallel with the second side surface S2 and be connected to the second portion R1-2. The first portion R1-1 and the third portion R1-3 may be formed to face each other.

[0078] Here, the depth of the first recess R1, which is the minimum distance between the second portion R1-2 and the first side surface S1, is referred to as a first depth d1 (see Figure 5). The width of the first recess R1 is defined as the width of the second portion R1-2 and is referred to as the first width w1 (see Figure 4 ).

[0079] The height of the first recess R1 is equal to the height of the second portion R1-2, and the height of the first recess R1 is greater than the first thickness t1 which is the thickness of the wiring layer 180. Therefore, the conductive pad 400 to be described may completely cover the exposed surface of the first recess wiring R1-a and a portion of the first display panel 100 and the second display panel 200 arranged adjacent to the first recess wiring R1-a.

[0080] The first portion R1 - 1 , the second portion R1 - 2 , and the third portion R1 - 3 of the first recess R1 are in contact with the conductive pad 400 .

[0081] The first portion R1-1 includes a first wiring R1-1a, the second portion R1-2 includes a second wiring R1-2a, and the third portion R1-3 includes a third wiring R1-3a. The first wiring R1-1a, the second wiring R1-2a, and the third wiring R1-3a may form a C-shaped first recessed wiring R1-a.

[0082] The second recess R2 includes a fourth portion R2-1, a fifth portion R2-2, and a sixth portion R2-3. The fourth portion R2-1, the fifth portion R2-2, and the sixth portion R2-3 may form a C-shaped second recess R2.

[0083] In detail, the fourth portion R2-1 may extend parallel to the second side S2, the fifth portion R2-2 may extend parallel to the first side S1 and be connected to the fourth portion R2-1, and the sixth portion R2-3 may extend parallel to the second side S2 and be connected to the fifth portion R2-2. The fourth portion R2-1 and the sixth portion R2-3 may be formed to face each other.

[0084] Here, the depth of the second recess R2, which is the minimum distance between the fifth portion R2-2 and the first side surface S1, is referred to as a second depth. The width of the second recess R2 is defined as the width of the fifth portion R2-2 and is referred to as a second width w2.

[0085] The fourth portion R2 - 1 , the fifth portion R2 - 2 , and the sixth portion R2 - 3 of the second recess R2 are in contact with the conductive pad 400 .

[0086] The fourth portion R2-1 includes a fourth wiring R2-1a, the fifth portion R2-2 includes a fifth wiring R2-2a, and the sixth portion R2-3 includes a sixth wiring R2-3a exposed to the outside. The fourth wiring R2-1a, the fifth wiring R2-2a, and the sixth wiring R2-3a extend to form a C-shaped second recessed wiring R2-a.

[0087] The shape of the recess R is not limited to the above-mentioned C-shape. According to an exemplary embodiment, it may have a U-shape, an inverted trapezoidal shape with a bottom side wider than a top side, and it may form a triangular shape including two parts having a predetermined angle between the first direction DR1 and the second direction DR2. The shape of the recess R is not limited thereto.

[0088] When the thickness of the wiring layer 180 is the first thickness t1 , the first thickness t1 may be about 5 μm to 20 μm, and for example, may be about 8.5 μm to 9.5 μm.

[0089] The first width w1 may be equal to or greater than the width of one data line. The first width w1 may be about 30 μm to about 100 μm, and for example, it may be about 70 μm to about 80 μm. The first depth d1 may be about 0.5 μm to about 10 μm, and for example, it may be about 2.5 μm to about 3.5 μm. As described above, the first thickness t1 as the thickness of the wiring layer 180 may be about 8.5 μm to about 9.5 μm.

[0090] Here, in addition to the second portion R1-2 of the first recess R1, the conductive pad 400 is also in direct contact with the first portion R1-1 and the third portion R1-3, and thus the contact area between the conductive pad 400 and the wiring layer 180 is increased in the first side S1 of the display panel 10. In particular, in addition to the second wiring R1-2a of the first recess wiring R1-a, the conductive pad 400 is also in contact with the first wiring R1-1a and the third wiring R1-3a, and thus the contact area of ​​the conductive pad 400 and the wiring layer 180 on the first display panel 100 can be increased, the adhesive force therebetween can be increased, and the adhesive force can be enhanced.

[0091] In addition, during the process of forming the first recess R1, residues such as organic materials on the first side S1 of the display panel 10 may be removed, and thus the conductive pad 400 is more firmly attached to the first side S1 of the display panel 10. Accordingly, when the flexible circuit board 500 is attached to the first side S1 of the display panel 10, an open circuit of the wiring layer 180 generated due to exposure of the wiring layer 180 on the first side S1 may be prevented.

[0092] As described above, since the first recess R1 is provided on the first side S1 of the display panel 10, the contact area between the wiring layer 180 of the display panel 10 and the conductive pad 400 attached to the first side S1 of the display panel 10 increases. Therefore, the adhesive force of the conductive pad 400 increases, and it can be firmly attached to the first side S1 of the display panel 10, so that the open circuit of the wiring layer 180 exposed on the first side S1 of the display panel 10 can be prevented, and thus the defect of the display device 1000 can be prevented.

[0093] For example, when the first width w1 is about 77 μm and the first thickness t1 is about 9 μm, when the first recess R1 is not formed in the first side surface S1, the exposed area of ​​the second wiring R1-2a is about 693 μm. 2 (77 μm×9 μm). That is, the contact area between the conductive pad 400 and the second wiring R1-2a may be about 693 μm 2 .

[0094] For example, when the first depth d1 as the depth of the first recess R1 is about 3 μm and the first thickness t1 is about 9 μm, the areas of the first portion R1-1 and the third portion R1-3 are about 27 μm, respectively. 2 That is, the contact area between the conductive pad 400 and the first portion R1-1 and the contact area between the conductive pad 400 and the third portion R1-3 may be approximately 27 μm, respectively. 2 In other words, the contact area between the conductive pad 400 and the wiring layer 180 is increased by the exposed areas of the first portion R1-1 and the third portion R1-3. Therefore, when the first recess R1 is formed in the first side S1, the total contact area may be about 747 μm 2 (693μm 2 +27×2μm 2 ).

[0095] As described above, regarding the display device 1000 according to the exemplary embodiment, when the first recess R1 is formed in the first side S1 of the display panel 10, the contact area may be increased from about 693 μm to about 10 μm, compared with a case where no recess is formed in the first side S1. 2 Increased to about 747 μm 2 That is, the contact area between the conductive pad 400 and the wiring layer 180 may be increased by about 7.7% by forming the first recess R1 on the first side S1 of the display panel 10. The increase in the contact area may be controlled by changing the first depth d1 of the first recess R1 as needed.

[0096] Now refer to Figure 5 , Figure 6 , Figure 7 and Figure 8 A display device 1000 according to an exemplary embodiment is described. Figure 5 , Figure 6 , Figure 7 and Figure 8 According to another exemplary embodiment, Figure 1 Hereinafter, descriptions that are the same as or similar to those provided in the above exemplary embodiments will be omitted or simplified, and different features will be mainly described.

[0097] Reference Figure 5 , the display device 1000 includes a display panel 10 , a flexible circuit board 500 attached to a first side S1 of the display panel 10 , and a driving circuit substrate 600 connected to the flexible circuit board 500 .

[0098] The display panel 10 includes a first display panel 100 and a second display panel 200 bonded to each other to face each other and a light control layer, for example, a liquid crystal layer 300 or a light emitting layer 300 disposed between the first display panel 100 and the second display panel 200. Figure 1 A case where the liquid crystal layer 300 is disposed between the two display panels 100 and 200 is exemplarily described, however, the display device 1000 according to the exemplary embodiment is not limited thereto.

[0099] The first display panel 100 may include a first substrate 110 , a first wiring layer 120 , a gate insulating layer 123 , a semiconductor layer 130 , and a second wiring layer 170 .

[0100] The first wiring layer 120 is disposed on the first substrate 110, and the first wiring layer 120 may include the same material as the gate electrode 124 of the transistor TR and the portion in contact with the conductive pad 400 and be formed simultaneously therewith. The gate insulating layer 123 is disposed on the first wiring layer 120 except for the portion of the first wiring layer 120 in contact with the conductive pad 400. The semiconductor layer 130 is disposed on the gate insulating layer 123 corresponding to the gate electrode 124 to overlap with the gate electrode 124.

[0101] The second wiring layer 170 is disposed on the semiconductor layer 130. The second wiring layer 170 may include the same material as the data line 171, the first electrode 173, and the second electrode 175 and may be formed simultaneously therewith. The first electrode 173 and the second electrode 175 are arranged on portions corresponding to respective ends of the semiconductor layer 130. When one of the first electrode 173 and the second electrode 175 is a source electrode, the other may be a drain electrode. The data line 171 may correspond to the reference electrode. Figure 1 The data lines DL are described, and the data lines 171 transmit data signals to the pixels PX.

[0102] The first wiring layer 120 and the second wiring layer 170 may include a conductive metal such as Ti or Cu. The first wiring layer 120 and the second wiring layer 170 may be configured as a single layer or a multilayer having at least two layers. For example, the first wiring layer 120 may include a first layer (not shown) made of Ti and a second layer (not shown) made of Cu, and the first layer (not shown) and the second layer (not shown) of the first wiring layer 120 may be approximately Thickness and approx. For example, the second wiring layer 170 may include a first layer (not shown) made of Ti and a second layer (not shown) made of Cu, and the first layer (not shown) and the second layer (not shown) of the second wiring layer 170 may be approximately Thickness and approx. Thickness.

[0103] The wiring layer 180 may include a first wiring layer 120 and a second wiring layer 170. Here, the thickness of the wiring layer 180 is defined as the thickness of a portion of the wiring layer 180 in contact with the conductive pad 400, which is referred to as a first thickness t1'. The portion forming the first thickness t1' may be a portion of the first wiring layer 120 and a portion of the second wiring layer 170. In this case, a portion of the first wiring layer 120 in contact with the conductive pad 400 may be a dummy gate line that is not connected to the gate electrode 124 supplying a gate signal, and a portion of the second wiring layer 170 in contact with the conductive pad 400 may be connected to the data line 171. In an exemplary embodiment, a portion of the second wiring layer 170 in contact with the conductive pad 400 may be a dummy data line that is not connected to the data line 171 supplying a data signal, and a portion of the first wiring layer 120 in contact with the conductive pad 400 may be connected to the gate electrode 124.

[0104] In an exemplary embodiment, the portion where the first thickness t1 ′ is formed may be one of a portion of the first wiring layer 120 and a portion of the second wiring layer 170 .

[0105] The gate electrode 124 , the semiconductor layer 130 , the first electrode 173 , and the second electrode 175 may configure the transistor TR. Figure 5 The transistor TR having a bottom gate structure is shown, however, the transistor TR may be a top gate structure in which the gate electrode 124 is disposed on the semiconductor layer 130 .

[0106] A passivation layer (not shown) and a pixel electrode (not shown) may be disposed on the transistor TR. The pixel electrode (not shown) may include indium tin oxide (ITO), indium zinc oxide (IZO), and indium tin zinc oxide (ITZO) as transparent electrode materials having excellent transmittance, conductivity, and thermal stability.

[0107] A first recess R1 is formed in the first side surface S1 of the display panel 10 .

[0108] The first recess R1 is recessed by a first depth d1 from the first side surface S1 in a direction (ie, second direction DR2) toward the center of the display panel 10. The portion recessed by the first depth d1 from the first side surface S1 is a second portion R1-2 of the first recess R1.

[0109] In the present exemplary embodiment, the height of the first recess R1 in the third direction DR3 (i.e., the height of the second portion R1-2) is greater than the first thickness t1' which is the thickness of the wiring layer 180. Therefore, the conductive pad 400 disposed to fill the first recess R1 may also contact a portion of the first display panel 100 and the second display panel 200 in addition to the wiring layer 180 in the first recess R1. By forming the first recess R1 to be greater than the thickness of the wiring layer 180, the adhesive force between the conductive pad 400 and the first side S1 of the display panel 10 may be increased.

[0110] On the first side S1 of the display panel 10, pads on the flexible circuit board 500 may be connected to the first recess R1. The flexible circuit board 500 is connected to the first recess R1 through the conductive pad 400 and the conductive adhesive film 440 disposed therebetween.

[0111] The flexible circuit board 500 may be a flexible printed circuit board (FPCB). In detail, the flexible circuit board 500 may be configured in a chip on film (COF) form. Accordingly, according to a tape carrier package (TCP) scheme, a data driver (DD) may be connected to the first display panel 100, the second display panel 200, and the drive circuit substrate 600. The flexible circuit board 500 may be bent to the bottom side of the first display panel 100 so that the drive circuit substrate 600 may be arranged on the bottom side of the first substrate 110.

[0112] The conductive pad 400 may be a metal mixed solution. For example, it may include Ag, a hardener, and a resin component. When the metal mixed solution is heat-treated, the hardener hardens the metal mixed solution. The resin is a plastic material, and it can support the solid metal to be liquefied.

[0113] Recently, in order to reduce the peripheral area NDA as a non-display area of ​​the display device, a side bonding method for bonding a circuit board or wiring on the side of the display panel has received attention. In order to implement the side bonding method, the first side of the display panel including the wiring can be ground by using a grinder. In the grinding process, organic residues including carbon C may be precipitated on the first side of the ground display panel. Therefore, the wiring layer 180 may be open due to the precipitated organic residue, which may be carbon C precipitated on the first side of the ground display panel.

[0114] In an exemplary embodiment of the present inventive concept, an open circuit of the wiring layer due to organic residues generated when the first side S1 of the display panel 10 is ground can be prevented by forming the first recess R1 on the first side S1 of the display panel 10, and the contact resistance between the conductive pad 400 and the wiring layer 180 can be reduced by increasing the contact area therebetween.

[0115] In detail, a portion of the conductive pad 400 is disposed to fill the first recess R1. Figure 5 , but since the conductive pad 400 fills the first recess R1, the conductive pad 400 contacts the second portion R1-2 and also contacts the first portion R1-1 and the third portion R1-3 disposed near the corresponding side surfaces of the second portion R1-2. That is, since the display panel 10 includes the first recess R1, the area in which the conductive pad 400 contacts the wiring layer 180 such as the first wiring layer 120 and the second wiring layer 170 increases. For example, the contact area of ​​the conductive pad 400 and the wiring layer 180 may be increased by the first recess R1 by the amount of the first depth d1×the first thickness t1′×2. Accordingly, when the flexible circuit board 500 or the driving circuit substrate 600 is electrically connected to the wiring layer 180 through the conductive pad 400, the contact resistance between the conductive pad 400 and the wiring layer 180 is reduced, and thus the efficiency of the display device 1000 may be improved.

[0116] The second display panel 200 may include a second substrate 210 , and a common electrode (not shown), a color filter CF, and a light blocking member BM disposed thereon.

[0117] The common electrode (not shown) may be disposed on the second substrate 210. The common electrode (not shown) may include indium tin oxide (ITO), indium zinc oxide (IZO), and indium tin zinc oxide (ITZO) as transparent electrode materials having excellent transmittance, conductivity, and thermal stability. The common electrode in the first recess R1 may be removed to prevent a short circuit between the conductive pad 400 and the common electrode.

[0118] A color filter CF and a light blocking member BM may be formed on the common electrode (not shown). The light blocking member BM is arranged between adjacent color filters CF to distinguish corresponding pixels PX (see Figure 1 ), preventing light leakage of the display device 1000 and improving contrast. In addition, the light blocking member BM clearly divides the corresponding areas of the color filter CF, so it can block light input to one area from being input to another area. Accordingly, it can play a role in preventing the mixing of different colors displayed by the display device 1000.

[0119] A liquid crystal layer 300 including liquid crystal molecules may be disposed between the first display panel 100 and the second display panel 200, and may further include a sealant SL, a dummy pattern DP, and a column spacer CS. The layer disposed between the first display panel 100 and the second display panel 200 may not be the liquid crystal layer 300, but may be various organic light emitting elements.

[0120] When the transistor TR is turned on according to the gate signal applied to the gate electrode 124, the data signal is applied to the pixel electrode (not shown) through the transistor TR, and an electric field is generated between the pixel electrode (not shown) and the common electrode (not shown). The liquid crystal molecules of the liquid crystal layer 300 are then rearranged according to the electric field, and the corresponding pixel PX can represent the grayscale corresponding to the data signal.

[0121] The sealant SL may prevent leakage of the liquid crystal layer 300 disposed between the first display panel 100 and the second display panel 200 , and may be disposed around edges of the first display panel 100 and the second display panel 200 to bond the first display panel 100 and the second display panel 200 .

[0122] The dummy pattern DP and the column spacer CS may be disposed near the conductive pad 400 outside the sealant SL. The dummy pattern DP may also be disposed on the transistor TR to protect the transistor TR from foreign particles such as moisture or dust particles. The dummy pattern DP may include an organic insulating material or an inorganic insulating material.

[0123] The dummy pattern DP may be disposed on the first substrate 110 and may contact the second wiring layer 170 of the transistor TR. The dummy pattern DP may be disposed on the first side S1, or may be disposed on four sides to surround the edges of the first display panel 100 and the second display panel 200 between the first display panel 100 and the second display panel 200 of the display panel 10. In another way, the dummy pattern DP may be disposed in an island shape to correspond to a region where the conductive pad 400 is disposed.

[0124] The column spacer CS is arranged on the dummy pattern DP. According to an exemplary embodiment, one of the column spacer CS and the dummy pattern DP may be omitted. In another way, the sealant SL may have an increased width to be arranged adjacent to the conductive pad 400 instead of the dummy pattern DP and the column spacer CS.

[0125] Reference Figure 6 , the first recess R1 is formed in a region corresponding to the first thickness t1'. That is, the height of the first recess R1 is equal to the first thickness t1'. In the case of the present exemplary embodiment, the recess R is formed on the portion where the conductive pad 400 contacts the wiring layer 180, thereby simplifying the process by reducing the process time, energy and cost when forming the recess R. Figure 4 In the illustrated exemplary embodiment, the contact area between the conductive pad 400 and the wiring layer 180 increases by an amount equal to the first depth d1×the first thickness ( t1 ′)×2.

[0126] Reference Figure 5 and Figure 7, the first recess R1 is disposed such that it is not filled with the conductive pad 400 but is filled with the conductive filler 450 . The conductive pad 400 is disposed on the conductive filler 450 .

[0127] The conductive filler 450 includes a material different from the metal included in the conductive pad 400. For example, when the conductive pad 400 is Ag, the conductive filler 450 may be a metal that is cheaper than Ag and different from Ag and has conductivity. For example, the conductive filler 450 may be a metal such as Cu. As described, by filling the first recess R1 with a material different from the conductive pad 400, short circuits of the wiring layers 180 arranged adjacent to each other can be more effectively prevented.

[0128] As mentioned above, refer to Figure 6 and Figure 8 , the first recess R1 is configured such that it may be filled not with the conductive pad 400 but with the conductive filler 450. By filling the first recess R1 with the conductive filler 450 of a different material, a short circuit of the wiring layer 180 may be further effectively prevented.

[0129] Now refer to Fig. 9 , Fig.10 , Fig.11 , Fig.12 and Fig.13 A method for manufacturing the display device 1000 according to an exemplary embodiment is described. Fig. 9 A block diagram of a method for manufacturing a display device 1000 according to an exemplary embodiment is shown, and Fig.10 , Fig.11 , Fig.12 and Fig.13 An exemplary embodiment is shown Fig. 9 1 is a perspective view of a display device 1000 at corresponding stages shown in FIG.

[0130] Reference Fig. 9 and Fig.10 , a first side of the display panel 10 to which the first display panel 100 and the second display panel 200 are bonded can be cleaned by atmospheric pressure plasma using a plasma cleaning device P (S100). The first display panel 100 includes a first wiring layer 120 and a second wiring layer 170. The first side includes at least one of a first side S1 and a second side S2. Contamination materials such as organic materials or Cu oxides remaining on the first side can be first removed by plasma cleaning. Thus, the conductive paste CP (see Fig.12 ) and the adhesion between the first side of the display panel 10.

[0131] Reference Fig.11, the side bonding portion of the first side of the display panel 10 where plasma cleaning is performed is heated with a laser L (S200). In this case, the laser L may generate a pulsed first laser beam having an energy of 1 W. The first side of the display panel 10 may be heated by applying the pulsed first laser beam. The heating may be repeated eight times. When the pulsed first laser beam is applied as described above, the residue of the organic material on the first side of the display panel 10 is first removed. As the number of applications of the pulsed laser beam increases, a recess R is formed on the first side of the display panel 10. In this case, recesses R of various shapes may be formed by controlling the source of the laser L.

[0132] The recess R includes a first recess R1 and a second recess R2. At least one of the first recess R1 and at least one of the second recess R2 may be formed. The horizontal width of the first recess R1 may be smaller than the horizontal width of the second recess R2.

[0133] Reference Fig.12 , a conductive paste CP is coated on the first side surface of the display panel 10 formed with the recess R (S300). The conductive paste CP is printed in a predetermined area on the first side surface S1 of the display panel 10 by a die-casting method using a printing scheme, and can be integrally formed. In another way, the conductive paste CP can be integrally formed in the predetermined area by spraying the conductive paste CP.

[0134] According to an exemplary embodiment, the coating area of ​​the conductive paste CP may be a portion of a first side surface of the display panel 10. However, it may be formed on a plurality of side surfaces.

[0135] The conductive paste CP may include a metal having conductivity. Depending on the exemplary embodiment, the metal may be Ag, Cu, Au, or Al, and for example, it may be Ag. The conductive paste CP is not limited thereto.

[0136] Although not shown, the conductive paste CP coated on the first side of the display panel 10 is heated by the laser L (S400). As described above, the conductive paste CP may be an Ag mixed solution including Ag, a hardener and a resin, so when the conductive paste CP is heated by the laser L, the hardener in the conductive paste CP may be hardened and the conductive paste CP may be fixed to the first side of the display panel 10. In this case, unlike step S200, the applied second laser beam may not be a pulse type beam but a continuous type beam. The hardening laser beam may focus heat on a desired portion of the first side of the display panel 10, thereby preventing heating of portions other than a predetermined area and preventing other portions from being damaged.

[0137] Through the hardening step of S400, the volatile material in the conductive paste CP is vaporized and the conductive material may remain. In addition, the conductive paste CP may be firmly fixed on the first side of the display panel 10, and the surface rigidity may be improved.

[0138] Reference Fig.13 , a conductive pad 400 is formed by patterning the hardened conductive paste CP using a laser L (S500).

[0139] The patterned laser beam may be of a pulse type as described in step S200. However, unlike step S200, the beam may be applied at a greater energy than that applied in step S200 (e.g., at an energy of 3 W). In a manner similar to the recess R forming process (step S200), various shapes of the conductive pad 400 may be etched by controlling the source of the laser beam.

[0140] As described, the conductive pad 400 may be formed on the first side of the display panel 10 by laser patterning corresponding to the shape of the recess R. The conductive pad 400 may include a first pad 410 and a second pad 420. The first pad 410 may be formed on a portion corresponding to the first recess R1, and the second pad 420 may be formed on a portion corresponding to the second recess R2.

[0141] In this case, by forming the recess R, the contact area between the conductive pad 400 and the wiring layer 180 increases, the open circuit of the wiring layer 180 exposed in the recess R can be prevented, and the contact resistance between the conductive pad 400 and the wiring layer 180 can be reduced.

[0142] Reference Figure 1 , circuit elements such as the flexible circuit board 500 and the driving circuit substrate 600 are attached to the conductive pads 400 , and thus electrical signals supplied therethrough may be transmitted to the display panel 10 through the conductive pads 400 .

[0143] While the inventive concept has been described in conjunction with what are presently considered to be practical exemplary embodiments, it is to be understood that the inventive concept is not limited to the disclosed embodiments. Rather, the inventive concept is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A display device, comprising: A display panel, the display panel comprising: a first substrate, the first substrate comprising a thin film transistor; a second substrate facing the first substrate; and a wiring layer arranged on the first substrate; and a flexible circuit board, wherein the flexible circuit board is arranged on a first side of the display panel, wherein the first side of the display panel includes a recessed portion, the wiring layer is exposed in the recessed portion on the first side, the flexible circuit board includes a conductive pad, and the conductive pad contacts the wiring layer in the recessed portion to electrically connect the flexible circuit board to the wiring layer, Among them, the recess includes a first recess arranged on the first substrate, and the recess also includes a second recess arranged on the second substrate and a third recess arranged on the wiring layer, the first recess, the second recess and the third recess are recessed from the first side to a first depth, and the first depth is 0.5μm to 10μm.

2. The display device according to claim 1, further comprising: a conductive filler arranged between the conductive pad and the wiring layer to fill the recess; The recess includes a plurality of recesses, and at least two recesses among the plurality of recesses have different widths.

3. The display device according to claim 1, wherein: The wiring layer includes a first wiring layer and a second wiring layer electrically connected to each other, the first wiring layer includes the same material as a gate electrode of the thin film transistor and is formed simultaneously with the gate electrode of the thin film transistor; and The second wiring layer includes the same material as the data line of the thin film transistor, and is formed simultaneously with the data line of the thin film transistor.

4. The display device according to claim 1, further comprising: a dummy pattern, the dummy pattern being arranged on the wiring layer to overlap the wiring layer, the dummy pattern being in direct contact with the conductive pad; as well as a columnar spacer, the columnar spacer being arranged on the dummy pattern to overlap the dummy pattern, the columnar spacer being in direct contact with the conductive pad, The height of the recess is greater than the thickness of the wiring layer, and the conductive pad completely fills the recess.

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