Display device

Abstract

A display device includes: a display panel including pad electrodes disposed on a pad region of a substrate; and a panel driving circuit attached to the pad region via an anisotropic conductive film including conductive balls, and the panel driving circuit including bumps connected to the pad electrodes via the conductive balls, wherein pad grooves defined by at least a portion of the pad electrodes are formed in a unit region where the pad electrodes are disposed.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2024-0196876, filed in Korea on December 26, 2024, which is incorporated herein by reference in its entirety for all purposes, as if fully set forth herein. Technical Field

[0003] This invention relates to a display device. Background Technology

[0004] Recently, flat panel display devices with excellent characteristics such as thinness, light weight and low power consumption have been widely developed and applied in various fields.

[0005] In flat panel display devices, light-emitting display devices equipped with light-emitting elements such as light-emitting diodes are display devices that emit light when charge is injected into the light-emitting layer formed between the anode and cathode, and electrons and holes pair up and then quench.

[0006] Recently, the resolution of light-emitting display devices has increased, leading to an increase in the number of pad electrodes and thus a need to reduce the spacing between them. However, the limited area for placing pad electrodes and the requirement for pad electrodes to have a contact surface larger than a certain size make it very difficult to reduce the spacing between them. Summary of the Invention

[0007] The advantage of this invention is that it provides a display device capable of reducing the pitch of the pad electrodes.

[0008] Additional features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practice of the invention. These and other advantages of the invention will be realized and attained by means of the structures specifically pointed out in the written description and its claims, as well as in the accompanying drawings.

[0009] To achieve these and other advantages and for the purposes of the invention, as specifically implemented and broadly described herein, a display device includes: a display panel including pad electrodes disposed on a pad region of a substrate; and a panel driving circuit attached to the pad region via an anisotropic conductive film comprising conductive balls, the panel driving circuit including bumps connected to the pad electrodes respectively via the conductive balls, wherein pad recesses defined by at least a portion of the pad electrodes are formed in a unit region where the pad electrodes are disposed. Furthermore, in another aspect, a display device includes: a display panel including a display area and a non-display area disposed around the display area; and a driving circuit portion for driving the display panel, wherein the non-display area includes the pad region, and a plurality of pad electrodes are disposed on a substrate in the pad region, wherein a pad recess is formed in at least one of the plurality of pad electrodes.

[0010] It should be understood that the foregoing general description and the following detailed description are illustrative and exemplary, and are intended to provide further explanation of the claimed invention. Attached Figure Description

[0011] The accompanying drawings, which are included to provide a further understanding of this disclosure and are incorporated in and constitute a part of this application, illustrate embodiments of the disclosure and, together with the specification, serve to explain the principles of the disclosure. In the drawings:

[0012] Figure 1 This is a schematic plan view illustrating the structure of the display device according to the first embodiment of the present invention;

[0013] Figure 2 This is a schematic side view illustrating the attachment of the display panel and panel driving circuit in a display device according to a first embodiment of the present invention.

[0014] Figure 3 This is a circuit diagram illustrating an example of the structure of a sub-pixel according to a first embodiment of the present invention;

[0015] Figures 4A to 6 These are cross-sectional views illustrating various examples of the structure of a pad recess formed in a pad electrode according to a first embodiment of the present invention;

[0016] Figures 7 to 9 These are cross-sectional views illustrating various examples of the structure of a pad recess formed in a pad electrode of a display device according to a second embodiment of the present invention;

[0017] Figure 10 and Figure 11These are cross-sectional views illustrating various examples of the structure of a pad groove formed in a pad electrode of a display device according to a third embodiment of the present invention;

[0018] Figure 12 and Figure 13 These are cross-sectional views illustrating various examples of the structure of a pad recess formed in a pad electrode of a display device according to a fourth embodiment of the present invention; and

[0019] Figure 14 This is a cross-sectional view illustrating an example of the structure of a pad groove formed in a pad electrode of a display device according to a fifth embodiment of the present invention. Detailed Implementation

[0020] The advantages and features of the present invention, as well as methods for implementing them, will become clear from the following detailed description of the embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various different forms, and only these embodiments complete the invention. The present invention is provided to fully inform those skilled in the art of this disclosure of its scope, and the invention is defined by the scope of the claims and their equivalents.

[0021] The shapes, dimensions, proportions, angles, quantities, etc., disclosed in the accompanying drawings used to illustrate embodiments of the present invention are illustrative, and the present invention is not limited to the content of the illustrations. Throughout the application, the same reference numerals denote the same parts.

[0022] Furthermore, in describing this invention, detailed descriptions of relevant prior art may be omitted if it is determined that such detailed descriptions unnecessarily obscure the subject matter of the invention. When terms such as "comprising," "including," "having," and "constituting" are used in this invention, other parts may be added unless "only" is used. When a component is indicated in the singular, the plural case is also included unless a specific description is provided.

[0023] When interpreting a component, it is interpreted as including a margin range even if there is no separate explicit description.

[0024] When describing positional relationships, for example, when the positional relationship between two parts is described as "above", "over", "below", "side", "under", etc., one or more other parts may be placed between the two parts unless "exactly" or "directly" is used.

[0025] When describing temporal relationships, such as when the time sequence is described as "after", "following", "before", etc., discontinuous situations may be included unless "directly" or "immediately" is used.

[0026] When describing the components of the present invention, terms such as first, second, etc., may be used. These terms are only used to distinguish the components from other components, and the nature, order, or number of the components is not limited by the terms.

[0027] The features of the various embodiments of the present invention may be partially or wholly connected or combined with each other, and may be linked and driven in various technical ways. The embodiments may be implemented independently of each other, or may be implemented together with related relationships.

[0028] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Furthermore, in the following embodiments, the same and similar reference numerals are assigned to the same and similar parts, and their detailed descriptions may be omitted.

[0029] <First Implementation Method>

[0030] Figure 1 This is a schematic plan view illustrating the structure of a display device according to a first embodiment of the present invention. Figure 2 This is a schematic side view illustrating the attachment of the display panel and panel driving circuit in a display device according to a first embodiment of the present invention. Figure 3 This is a circuit diagram illustrating an example of the structure of a sub-pixel according to a first embodiment of the present invention.

[0031] Before describing it in detail, the display device 10 according to the first embodiment of the present invention can be any type of display device equipped with a pad electrode PE connected to the driving circuit.

[0032] In this embodiment, for ease of explanation, a light-emitting display device equipped with a light-emitting diode OD (more specifically, an organic light-emitting display device) can be used as an example of display device 10.

[0033] When the display device 10 is configured as a light-emitting display device, the display device 10 can be a top-emitting display device or a bottom-emitting display device.

[0034] Reference Figures 1 to 3 The display device 10 in this embodiment may include a display panel 100 for displaying images and a driving circuit portion for driving the display panel 100.

[0035] The driving circuit section may include a panel driving circuit PDC and a gate driving circuit 210.

[0036] In the display panel 100, a display area AA that substantially displays an image and a non-display area NA arranged around the display area AA can be defined.

[0037] The display area AA may include multiple sub-pixels SP arranged along multiple row lines (or horizontal lines) and multiple column lines (or vertical lines) on the substrate 101.

[0038] Additionally, multiple gate lines (or scan lines) GL extending in the row direction (or horizontal direction or a first direction) and multiple data lines DL extending in the column direction (or vertical direction or a second direction) can be formed on the substrate 101. Each sub-pixel SP can be connected to the corresponding gate line GL and data line DL.

[0039] Furthermore, power lines for transmitting a high-potential driving voltage (or high-potential power supply voltage) VDD and a low-potential driving voltage (or low-potential power supply voltage) VSS can be formed on the substrate 101. The high-potential driving voltage VDD and the low-potential driving voltage VSS can be applied to the sub-pixel SP.

[0040] The plurality of subpixels SP formed on the substrate 101 may include subpixels SP of different colors that constitute pixels as units for displaying color images. For example, the subpixels SP constituting a pixel may include first, second, and third subpixels SP that display a first color, a second color, and a third color, respectively, such as blue, green, and red subpixels SP that display blue, green, and red, respectively. As another example, the subpixels SP constituting a pixel may further include white subpixels that display white.

[0041] The red, green, and blue subpixels SP can be arranged in various configurations. For example, the subpixels SP can be arranged in a strip pattern where subpixels SP of the same color are arranged along the column direction and subpixels SP of different colors are arranged alternately along the row direction, but this is not limited to this.

[0042] Each sub-pixel SP may include a light-emitting diode OD as a light-emitting element. Furthermore, the sub-pixel SP may include a pixel driving circuit for driving the light-emitting diode OD. The pixel driving circuit may include a plurality of transistors including a driving transistor Td and at least one capacitor. In this configuration, during the light-emitting period, the driving transistor Td may be turned on to generate a light-emitting current, and this light-emitting current may be supplied to the light-emitting diode OD, thereby performing the light-emitting operation.

[0043] For reference Figure 3 The structure of a subpixel SP is described as an example. Figure 3 For ease of explanation, the pixel driving circuit for driving sub-pixels SP is shown as a 3T1C structure with three transistors T1, T2, and Td and a capacitor Cst. Additionally, Figure 3 The structure is an example, and the pixel driving circuit can be configured to have different structures.

[0044] In the following description, the transistor terms “source electrode” and “drain electrode” are used to distinguish the two electrodes connected to the semiconductor layer, and may be referred to as opposite terms in some cases.

[0045] The sub-pixel SP may include a first transistor T1 and a second transistor T2 as switching transistors, a driving transistor Td, a storage capacitor Cst, and a light-emitting diode OD. The first transistor T1 may be a data supply transistor, and the second transistor T2 may be a driving characteristic sensing transistor.

[0046] The first transistor T1 can be connected to the corresponding gate line GL and data line DL. In this respect, the drain electrode (or source electrode) of the first transistor T1 can be connected to the data line DL, and the gate electrode of the first transistor T1 can be connected to the gate line GL.

[0047] The driving transistor Td may have a gate electrode connected to the source electrode of the first transistor T1, a drain electrode (or source electrode) to which a high-potential driving voltage VDD is applied, and a source electrode (or drain electrode) connected to the anode electrode (or first electrode) of the light-emitting diode OD.

[0048] The second transistor T2 can be connected to the corresponding gate line GL and reference line RL. In this respect, the drain electrode (or source electrode) of the second transistor T2 can be connected to the reference line RL, the gate electrode of the second transistor T2 can be connected to the gate line GL, and the source electrode (or drain electrode) of the second transistor T2 can be connected to the node between the driving transistor Td and the light-emitting diode OD. In other words, the source electrode of the second transistor T2 can be connected to the source electrode of the driving transistor Td and the anode electrode of the light-emitting diode OD.

[0049] Thus, in this embodiment, an example is taken where the second transistor T2 and the first transistor T1 within the sub-pixel SP are connected to the same gate line GL and receive the same gate signal. As another example, the second transistor T2 may be configured to be connected to a different gate line GL than the gate line GL to which the first transistor T1 is connected.

[0050] The cathode (or second electrode) of the light-emitting diode OD can receive a low-potential drive voltage VSS. The low-potential drive voltage VSS can be a voltage having a potential lower than the high-potential drive voltage VDD, and may include a ground voltage.

[0051] The storage capacitor Cst can be connected between the gate electrode and the source electrode of the driving transistor Td.

[0052] In the above configuration, during operation in the display mode for displaying an image, when a gate signal with a conduction level is applied through the gate line GL, the first transistor T1 is turned on, and a data signal (or data voltage) can be input to the sub-pixel SP, so that the data signal can be applied to the gate electrode of the driving transistor Td. At this time, the second transistor T2 is turned on, so that a reference voltage can be applied to the source electrode of the driving transistor Td. Therefore, the data signal and the reference voltage can be applied to the two electrodes of the storage capacitor Cst, and as a result, the data signal can be stored in the storage capacitor Cst.

[0053] Then, when a gate signal at a cutoff level is applied through the gate line GL, the first transistor T1 and the second transistor T2 can be turned off, the driving transistor Td can be turned on, and the light-emitting current (or driving current) corresponding to the applied data signal can flow to the light-emitting diode OD through the driving transistor Td. Therefore, during the light-emitting period, light corresponding to the light-emitting current can be generated and output from the light-emitting diode OD.

[0054] Furthermore, during operation in compensation mode for compensating the driving transistor Td, a sensed data signal can be applied to the sub-pixel SP, and a sensed voltage can be provided to the reference line RL via the second transistor T2. Based on the sensed voltage, the data signal used for image display can be compensated, and the compensated data signal can be applied to the sub-pixel SP to compensate the driving transistor Td.

[0055] The display panel 100 configured as described above can be driven using the gate drive circuit 210 and the panel drive circuit PDC that constitute the drive circuit portion.

[0056] A gate drive circuit 210 for applying gate signals to gate lines GL can be formed, for example, in the non-display area NA of the display panel 100.

[0057] In this respect, the gate driving circuit 210 can be formed as a GIP (gate in panel) type. During the process of forming the pixel driving circuit, the GIP type gate driving circuit 210 can be formed directly in the non-display area NA.

[0058] In addition, to ensure stable operation of the display panel 100, the GIP-type gate drive circuit 210 may be formed on opposite sides of the display area AA, for example, in the left non-display area and the right non-display area NA.

[0059] As another example, the gate drive circuit 210 may be configured with at least one IC and mounted on the substrate 101 in a COG type or connected to the substrate 101 in a COF type.

[0060] The panel driver circuit PDC can output various driving signals to drive the display panel 100.

[0061] In this regard, for example, the panel driver circuit PDC can output data signals. Furthermore, the panel driver circuit PDC can output gate control signals to control the operation of the gate driver circuit 210.

[0062] In this way, the drive signal output from the panel drive circuit PDC can be provided to the pad electrode PE formed on the substrate 101 of the display panel 100, and the drive signal applied to the pad electrode PE can be transmitted through the corresponding line connected thereto.

[0063] In this regard, for example, when a data signal is applied to the corresponding pad electrode (or data pad electrode) PE, the data signal can be transmitted to the corresponding sub-pixel SP via the data line DL connected to the pad electrode PE. Furthermore, when a gate control signal is applied to the corresponding pad electrode (or control pad electrode) PE, the gate control signal can be transmitted to the gate drive circuit 210 via the connection to the pad electrode PE.

[0064] The panel driving circuit PDC can be attached (or connected or combined) to one side of the non-display area NA of the display panel 100, such as the upper non-display area NA.

[0065] The panel driver circuit PDC can be configured as, for example, COF type, but is not limited to this. When the panel driver circuit PDC is configured as COF type, the panel driver circuit PDC may include, for example, a driver IC DIC and a circuit film (or flexible circuit film) FPC on which the driver IC DIC is mounted.

[0066] In this respect, the driver IC (DIC) can output, for example, data signals, more specifically, data voltages.

[0067] The circuit film FPC can be attached to the display panel 100 with a driver IC DIC mounted on it. The circuit film FPC may have multiple bumps BP, which are multiple output terminals formed on the bottom surface (or lower surface) of the circuit film FPC for outputting drive signals.

[0068] In addition, multiple pad electrodes PE can be arranged in the pad area PA, which is the non-display area NA of the display panel 100 attached to the circuit film FPC, and the multiple pad electrodes PE can be respectively connected to multiple bumps BP arranged on the circuit film FPC.

[0069] Therefore, the drive signal output from each bump BP of the circuit film FPC can be applied to the pad electrode PE connected to the bump BP and transmitted to the display panel 100.

[0070] For example, multiple pad electrodes PE can be arranged along the extension direction (or length direction) of the pad area PA of the attached circuit film FPC. In this embodiment, the pad electrodes PE can be arranged in two rows along the horizontal direction (or transverse direction) of the pad area PA, but are not limited thereto.

[0071] In addition, when the panel driving circuit PDC is attached to the display panel 100, an anisotropic conductive film ACF can be inserted between the panel driving circuit PDC and the display panel 100 to ensure the electrical connection between the corresponding bump BP and the pad electrode PE.

[0072] In this regard, refer to Figure 2 The anisotropic conductive film ACF, which is inserted between the panel driving circuit PDC and the display panel 100, may include conductive balls CB dispersed therein. For example, the anisotropic conductive film ACF may be configured with conductive balls CB dispersed in a thermoplastic resin or a thermosetting resin.

[0073] When the anisotropic conductive film (ACF) is inserted, pressure can be applied towards the display panel 100, causing the bump BP of the panel driving circuit PDC to press against the pad electrode PE of the display panel 100. Therefore, the conductive ball CB located between the corresponding bump BP and the pad electrode PE can be pressed and deformed by the pressure, thereby bringing the conductive layer of the conductive ball CB into contact with both the bump BP and the pad electrode PE. Thus, the bump BP and the pad electrode PE can be electrically connected to each other through the conductive ball CB inserted between them.

[0074] As described above, the pad electrode PE of the display panel 100 and the bump BP of the panel driving circuit PDC can be connected to each other through the conductive ball CB of the anisotropic conductive film ACF. Therefore, the driving signal output from the panel driving circuit PDC through the bump BP can be applied to the pad electrode PE and transmitted to the interior of the display panel 100.

[0075] Furthermore, in this embodiment, regarding the pad electrode PE arranged in the pad area PA of the display panel 100, a pad recess (or pad hole) PH can be formed within the pad electrode PE. The pad recess (or pad hole) PH is a recess (or hole) that is recessed in a downward direction toward the substrate 101. In other words, the pad electrode PE can be constructed as a bowl shape with the pad recess PH formed therein.

[0076] Therefore, when a pad groove PH is formed in the pad electrode PE, the inner surface (or internal surface) of the pad electrode PE surrounding and defining the pad groove PH can also be used as a connection surface (or contact surface), thus increasing the connection surface of the pad electrode PE.

[0077] In other words, by forming a pad electrode PE in which a pad groove PH is formed, the inner surface extending in the depth direction of the pad groove PH can be added as a connection surface, thereby increasing the connection surface of the pad electrode PE.

[0078] Therefore, the size (or width) of each pad electrode PE can be reduced, that is, the planar area of ​​each pad electrode PE can be reduced, which in turn reduces the spacing between the arranged pad electrodes PE.

[0079] Therefore, even if the resolution of the display device 10 increases, the pad electrodes PE can be arranged with a narrow pitch.

[0080] The structure of the pad electrode PE having a pad groove PH formed therein can be described in more detail below.

[0081] Figures 4A to 6 These are cross-sectional views illustrating various examples of the structure of the pad recess formed in the pad electrode according to a first embodiment of the present invention. For ease of explanation, Figures 4A to 6 The structures of the pad recesses shown are referred to as the structures of the first example to the third example, respectively.

[0082] Reference Figures 4A to 6 The pad electrode PE can be arranged in the pad area PA on the substrate 101 of the display panel 100.

[0083] The substrate 101 can be an insulating substrate such as a glass substrate or a plastic substrate. As another example, the substrate 101 can be a silicon substrate (or silicon wafer) formed from crystalline silicon (e.g., single-crystal silicon) used as a semiconductor, and in this case, it is advantageous to efficiently realize small-sized display devices requiring high resolution. In this embodiment, an insulating substrate is used as an example for ease of illustration.

[0084] The pad electrode PE can be formed of a conductive metal, such as Mo, Al, Cu or Ti, but is not limited to these.

[0085] Additionally, within the pad area PA, the unit area where each pad electrode PE is formed can be referred to as a unit pad area. Each pad electrode PE may have a pad groove PH that is recessed downward therein.

[0086] In this configuration, the pad electrode PE may have an inner surface defining the pad recess PH. In this regard, the pad electrode PE may have an inner surface surrounding the pad recess PH along its outer periphery, and a bottom surface below the pad recess PH. In other words, the pad electrode PE may include a sidewall portion SW surrounding the pad recess PH along its outer periphery, and a bottom portion BO located below the pad recess PH.

[0087] In addition, an insulating layer (ISL) can be inserted between adjacent pad electrodes (PE). In other words, adjacent pad electrodes (PE) can be physically separated (or distinguished) by the insulating layer (ISL).

[0088] In this way, the insulating layer ISL can be used as a partition wall separating the pad electrodes PE. For example, the insulating layer ISL can be configured such that an opening is formed inside the insulating layer ISL and each pad electrode PE is inserted into a corresponding opening.

[0089] The insulating layer ISL can be formed from inorganic insulating materials and / or organic insulating materials.

[0090] Here, the size (or width or planar area) of the pad groove PH of the pad electrode PE can be formed to be equal to or greater than the size (or diameter or planar area) of the conductive ball CB. When the bump BP of the panel drive circuit PDC is pressed against the pad electrode PE of the display panel 100 with a certain pressure, the pad electrode PE can deform while being pressed, so that the conductive ball CB can contact the bump BP and the pad electrode PE.

[0091] As another example, see Figure 4B The depth of the pad recess PH or the height of the sidewall portion SW of the pad recess PH can be less than the size (or diameter) of the conductive ball CB. Therefore, a portion of the upper part of the conductive ball CB can protrude from the end (or top) of the pad recess PH, and when the bump BP of the panel drive circuit PDC presses against the pad electrode PE of the display panel 100, the conductive ball CB can be pressed down by the pressure and can firmly contact the bump BP and the pad electrode PE. Embodiments of the present invention are not limited thereto, and the pad recess PH and the conductive ball CB can be formed in various sizes.

[0092] In this embodiment, for ease of explanation, as an example, it is shown that the pad recess PH is formed such that the conductive ball CB is located within the pad recess PH.

[0093] The pad grooves PH of the pad electrode PE can be formed into various shapes.

[0094] In this regard, Figure 4A and Figure 4B In the first example, when viewed in cross-section, the pad recess PH can have a generally rectangular shape. In other words, the pad recess PH can be formed as a rectangular shape with a constant width in the depth direction of the pad recess PH.

[0095] In addition, Figure 5In the second example, when viewed in cross-section, the pad recess PH can have a generally trapezoidal shape with a narrower width at the bottom. In other words, in the depth direction of the pad recess PH, the pad recess PH can be formed as a trapezoidal shape that becomes narrower towards the bottom.

[0096] In addition, Figure 6 In the third example, when viewed in cross-section, the pad recess PH can be formed such that the bottom surface (or the upper surface of the bottom portion BO) has a rounded shape. That is, in the depth direction of the pad recess PH, the pad recess PH is formed with a rectangular upper part of constant width and a rounded lower part that becomes narrower towards the bottom.

[0097] As described above, in this embodiment, the pad electrode PE may be formed with a pad groove PH recessed therein.

[0098] Therefore, the inner surface extending in the depth direction of the pad groove PH can be added to the pad electrode PE as a connection surface, thereby increasing the connection surface.

[0099] Therefore, the area occupied by the pad electrode PE can be reduced, and thus the spacing of the pad electrode PE can be reduced.

[0100] Therefore, even if the resolution of the display device 10 increases, the pad electrodes PE can be arranged with a narrow pitch, so that the pad electrodes PE can be effectively formed even at high resolution.

[0101] <Second Implementation Method>

[0102] Figures 7 to 9 This is a cross-sectional view illustrating various examples of the structure of the pad recess formed in the pad electrode of the display device according to a second embodiment of the present invention. For ease of explanation, Figures 7 to 9 The structures of the pad recesses shown are referred to as the structures of the first example to the third example, respectively.

[0103] In the following description, detailed descriptions of components that are the same as or similar to those in the first embodiment may be omitted.

[0104] Similar to the first embodiment, the pad electrode PE of the display device according to the second embodiment of the present invention may have pad recesses PH formed therein to increase the bonding surface. This allows for a reduction in the size of the pad electrode PE, thereby reducing the spacing between the pad electrodes PE.

[0105] In addition, the pad groove PH of the pad electrode PE in the second embodiment can be formed to have a concave-convex structure.

[0106] In this regard, refer to Figures 7 to 9The inner surface of the pad electrode PE surrounding the pad groove PH and the bottom surface of the pad electrode PE below the pad groove PH can be formed with an uneven shape, such that protrusions PP protruding inward toward the pad groove PH and recesses inward from the pad groove PH are repeatedly arranged.

[0107] In other words, in the pad electrode PE, protrusions PP can be provided on the inner surface of the pad electrode PE at specified intervals and protrude toward the pad groove PH, and a recessed space can be defined between adjacent protrusions PP.

[0108] In this way, when the pad groove PH is formed using a concave-convex structure, the area of ​​the inner surface of the pad electrode PE can be further increased, thereby further increasing the connection surface of the pad electrode PE.

[0109] Alternatively, an insulating layer (ISL) can be inserted between adjacent pad electrodes (PE), allowing adjacent pad electrodes (PE) to be physically separated through the insulating layer (ISL).

[0110] The uneven structure of the pad groove (PH) can be formed into various shapes.

[0111] In this regard, Figure 7 In the first example, the protrusions PP of the pad electrode PE can be arranged at predetermined intervals. For example, the protrusions PP can be formed to have a generally constant width, and the recessed space between adjacent protrusions PP can be formed to be a rectangular shape with a generally constant width. In other words, when the end of the protrusion PP facing the pad recess PH is referred to as the first end and the other end of the protrusion PP opposite the first end is referred to as the second end, the first ends of adjacent protrusions PP can be spaced apart from each other by a constant distance, and the second ends of adjacent protrusions PP can also be spaced apart from each other by a constant distance.

[0112] In addition, Figure 8 In the second example, the protrusions PP of the pad electrode PE can be formed with a shape whose width increases outward from the pad recess PH. Furthermore, the second ends of adjacent protrusions PP can be formed to contact each other. In the second example, the separation region between adjacent protrusions PP can be formed with a generally triangular shape.

[0113] In addition, Figure 9 In the third example, similar to Figure 8 In a second example, the protrusions PP of the pad electrode PE can be formed with a shape whose width increases outward from the pad recess PH. Furthermore, the second ends of adjacent protrusions PP can be formed to contact each other. In a third example, the separation region between adjacent protrusions PP can be formed with a generally rounded shape.

[0114] <Third Implementation Method>

[0115] Figure 10 and Figure 11 This is a cross-sectional view illustrating various examples of the structure of a pad recess formed in a pad electrode of a display device according to a third embodiment of the present invention. For ease of explanation, in Figure 10 and Figure 11 The structures of the pad recesses shown are referred to as the first example and the second example, respectively.

[0116] In the following description, detailed descriptions of components that are the same as or similar to those in the first and / or second embodiments may be omitted.

[0117] Similar to the first and / or second embodiments, the pad electrodes PE of the display device according to the third embodiment of the present invention may have pad recesses PH formed therein to increase the connection surface. Therefore, the size of the pad electrodes PE can be reduced, thereby reducing the spacing between the pad electrodes PE.

[0118] Furthermore, similar to the second embodiment, the pad groove PH of the pad electrode PE in the third embodiment can be formed with an uneven structure, further increasing the connection surface.

[0119] In addition, in the third embodiment, the pad recess PH can be defined by being surrounded by the inner surface of the pad electrode PE and the inner surface of the insulating layer ISL.

[0120] Furthermore, a conductive film CL can be deposited along the inner surface of the pad electrode PE that defines the pad recess PH and the inner surface of the insulating layer ISL, so that the conductive film CL can substantially define the pad recess PH. Here, the conductive film CL can be formed of a metal with conductive properties, such as, but not limited to, Mo, Al, Cu, or Ti.

[0121] The conductive film CL is in contact with the pad electrode PE, so that the combination of the conductive film CL and the pad electrode PE can be used as a unit pad electrode including the pad groove PH.

[0122] In this regard, refer to Figure 10 In a first example, the pad electrode PE can be formed, for example, such that the sidewall portion SW has a first groove (or a first hole) Hs. In this respect, at least one first groove Hs can be formed in the sidewall portion SW, and the insulating layer ISL in contact with the outer side of the sidewall portion SW can be configured to be exposed to the pad groove PH through the first groove Hs. In this case, the sidewall portion SW can be configured to include patterned portions that are vertically spaced apart with the first groove Hs interposed between them.

[0123] In addition, the bottom portion BO of the pad electrode PE may not have a groove formed therein, but may be formed continuously throughout.

[0124] In this case, since the side surface of the pad recess PH can be defined approximately by the inner surface of the pad electrode PE and the inner surface of the insulating layer ISL (i.e., the side surface of the insulating layer ISL exposed through the first recess Hs), the side surface of the pad recess PH can be configured to be concave-convex.

[0125] Furthermore, since the bottom surface of the pad recess PH can be roughly defined by the bottom surface of the pad electrode PE, the bottom surface of the pad recess PH can be configured to be a flat shape.

[0126] In this case, the conductive film CL can cover the inner surface of the pad electrode PE that defines the pad groove PH and the inner surface of the insulating layer ISL.

[0127] The conductive film CL can be formed along the side and bottom surfaces of the pad recess PH in a shape that is substantially the same as the side and bottom surfaces of the pad recess PH. Therefore, the conductive film CL can substantially surround and define the pad recess PH.

[0128] The conductive thin film CL can be formed to have a thickness smaller than that of the pad electrode PE.

[0129] Reference Figure 11 The second example is similar to Figure 10 In a first example, the pad electrode PE can be formed such that the sidewall portion SW has a first groove Hs. Alternatively, the sidewall portion SW can be formed without a groove.

[0130] Furthermore, the bottom portion BO of the pad electrode PE can, for example, be formed as a second groove (or second hole) Hb similar to the sidewall portion SW. In this respect, at least one second groove Hb can be formed in the bottom portion BO, and a portion of the substrate 101 below the bottom portion BO can be configured to be exposed to the pad groove PH through the second groove Hb. In this case, the bottom portion BO can be configured to include a patterned portion disposed between the second grooves Hb.

[0131] In this case, since the side surface of the pad recess PH can be defined approximately by the inner surface of the pad electrode PE and the inner surface of the insulating layer ISL, the side surface of the pad recess PH can be configured as an uneven shape.

[0132] Furthermore, since the bottom surface of the pad recess PH can be defined approximately by the bottom surface of the pad electrode PE and the bottom surface of the substrate 101 (i.e., the surface of the substrate 101 exposed by the second recess Hb), the bottom surface of the pad recess PH can be configured to have an uneven shape.

[0133] In this case, the conductive film CL can cover the inner surface of the pad electrode PE that defines the pad groove PH, the inner surface of the insulating layer ISL, and the surface of the substrate 101.

[0134] The conductive film CL can be formed along the side and bottom surfaces of the pad recess PH in a shape that is substantially the same as the side and bottom surfaces of the pad recess PH. Therefore, the conductive film CL can substantially surround and define the pad recess PH.

[0135] The conductive thin film CL can be formed to have a thickness smaller than that of the pad electrode PE.

[0136] As described above, in this embodiment, the combination of the pad electrode PE and the conductive film CL, which is in contact with the inner surface of the pad electrode PE and formed along the pad groove PH, can be generally used as a unit pad electrode. Therefore, the pad electrode PE can be used as a first electrode, the conductive film CL, which is in direct contact with the conductive ball CB, can be used as a second electrode, and the combination of the first electrode and the second electrode can be considered to constitute a pad electrode.

[0137] <Fourth Implementation Method>

[0138] Figure 12 and Figure 13 This is a cross-sectional view illustrating various examples of the structure of the pad recess formed in the pad electrode of the display device according to a fourth embodiment of the present invention. For ease of explanation, Figure 12 and Figure 13 The structures of the pad recesses shown are referred to as the first example and the second example, respectively.

[0139] In the following description, detailed descriptions of components that are the same as or similar to those in the first, second, and / or third embodiments may be omitted.

[0140] In the display device according to the fourth embodiment of the present invention, the pad recess PH can be defined by being surrounded by the inner surface of the pad electrode PE and the inner surface of the insulating layer ISL, and the pad recess PH can be formed in a shape similar to that of the first embodiment.

[0141] Furthermore, similar to the third embodiment, the conductive film CL can be deposited along the side and bottom surfaces of the pad recess PH, thereby allowing the conductive film CL to substantially define the pad recess PH.

[0142] Therefore, in this embodiment, a pad groove PH can be formed in the combination of the pad electrode PE constituting the unit pad electrode and the conductive film CL, thereby increasing the connection surface. Thus, the size of the pad electrode PE can be reduced, thereby reducing the spacing between the pad electrodes PE.

[0143] In this regard, refer to Figure 12 In a first example, the pad electrode PE may be configured with a bottom portion BO but without a sidewall portion. In other words, the pad electrode PE may be formed as a conductive film of a certain thickness laminated onto the substrate 101.

[0144] In this case, the pad recess PH can be defined in a combination of a pad electrode PE formed as the bottom portion BO and an insulating layer ISL arranged along the outer periphery of the pad electrode PE and serving as a partition wall.

[0145] In this case, the pad recess PH can be surrounded by the insulating layer ISL, such that the side surface of the pad recess PH can be defined by the inner surface of the insulating layer ISL.

[0146] In addition, the pad electrode PE can be positioned below the pad recess PH, so that the bottom surface of the pad recess PH can be defined by the upper surface of the pad electrode PE.

[0147] In this case, the conductive film CL can cover the inner surface of the pad electrode PE that defines the pad groove PH and the insulating layer ISL.

[0148] The conductive film CL can be formed along the side and bottom surfaces of the pad recess PH in a shape that is substantially the same as the side and bottom surfaces of the pad recess PH. Therefore, the conductive film CL can substantially surround and define the pad recess PH.

[0149] The conductive thin film CL can be formed to have a thickness smaller than that of the pad electrode PE.

[0150] Reference Figure 13 In a second example, the pad electrode PE may, for instance, be configured with a bottom portion BO without a sidewall portion. The pad electrode PE of the second example may be formed having a... Figure 12 The first example has a narrow PE pad electrode.

[0151] In this case, the pad recess PH can be defined in a combination of a pad electrode PE configured as a narrow bottom portion BO and an insulating layer ISL arranged along the outer periphery of the pad electrode PE.

[0152] In this case, the insulating layer ISL can be configured to have, for example, a first portion ISL1 serving as a partition wall and a second portion ISL2 serving as a bottom.

[0153] The first part, ISL1, can roughly correspond to... Figure 12 The first example is an insulating layer ISL, which may surround the pad recess PH. Therefore, the side surface of the pad recess PH may be defined by the inner surface of the first portion ISL1 of the insulating layer ISL.

[0154] The second part ISL2 and the pad electrode PE, which is formed as a narrow bottom portion BO, can be disposed below, for example, the pad recess PH. Therefore, the bottom surface of the pad recess PH can be defined by the upper surface of the second part ISL2 of the insulating layer ISL and the upper surface of the pad electrode PE.

[0155] Additionally, the second portion ISL2 of the insulating layer ISL may include, for example, a groove (or a third groove) Hi in which a pad electrode PE is disposed (or inserted). Therefore, the combination of the second portion ISL2 of the insulating layer ISL and the pad electrode PE disposed in the groove Hi can be disposed below the pad groove PH.

[0156] In this case, the conductive film CL can cover the inner surface of the pad electrode PE that defines the pad groove PH and the insulating layer ISL.

[0157] The conductive film CL can be formed along the side and bottom surfaces of the pad recess PH in a shape that is substantially the same as the side and bottom surfaces of the pad recess PH. Therefore, the conductive film CL can substantially surround and define the pad recess PH.

[0158] The conductive thin film CL can be formed to have a thickness smaller than that of the pad electrode PE.

[0159] As described above, in this embodiment, the combination of the conductive film CL, which is in contact with the inner surface of the pad electrode PE and the insulating layer ISL and is formed along the pad groove PH, and the pad electrode PE can be used as a unit pad electrode. Therefore, the pad electrode PE can be used as a first electrode, the conductive film CL, which is in direct contact with the conductive ball CB, can be used as a second electrode, and the combination of the first electrode and the second electrode can be considered to constitute a pad electrode.

[0160] As described above, in this embodiment, the sidewall portion of the pad electrode PE can be omitted. Therefore, the size of the pad electrode PE can be further reduced, and thus the spacing of the pad electrode PE can be further reduced.

[0161] <Fifth Implementation Method>

[0162] Figure 14 This is a cross-sectional view illustrating an example of the structure of a pad groove formed in a pad electrode of a display device according to a fifth embodiment of the present invention.

[0163] In the following description, detailed descriptions of components that are the same as or similar to those in the first, second, third, and / or fourth embodiments may be omitted.

[0164] In the display device according to the fifth embodiment of the present invention, a pad recess PH can be formed in the unit pad region where the pad electrode PE is formed, similar to the first to fourth embodiments. For example, the pad recess PH can be configured to be defined by being surrounded by the sidewall portion SW of the pad electrode PE, the insulating layer ISL disposed outside the sidewall portion SW, and the upper surface of the insulating layer IL3 disposed below the sidewall portion SW. A pad recess PH similar to the first example of the third embodiment (see...) Figure 10The side surface of the pad groove PH can be configured as a concave-convex shape.

[0165] Similar to the third and fourth embodiments, the conductive film CL can be deposited along the side and bottom surfaces of the pad recess PH, thereby allowing the conductive film CL to substantially define the pad recess PH.

[0166] Furthermore, unlike the previously described embodiments, the pad electrode PE in this embodiment may be configured to include a base portion BA covered by an insulating layer formed below the pad recess PH, without a bottom portion directly below the pad recess PH. Figures 4A to 13 (BO). The substrate portion BA can contact the conductive film CL through contact holes CH formed in the insulating layer covering the substrate portion BA.

[0167] The structure of the pad recess PH and pad electrode PE configured in this way is described below.

[0168] In this embodiment, the pad electrodes PE disposed in the pad area PA may include pad electrodes PE with base portions BA of different heights. For ease of illustration, the pad electrodes PE disposed in the pad area PA are illustrated as three pad electrodes, namely, first pad electrodes PE1 to third pad electrodes PE3 with corresponding base portions BA of different heights. The first pad electrodes PE1 to third pad electrodes PE3 may be arranged adjacent to each other and may be arranged alternately and repeatedly in the pad area PA.

[0169] The first pad electrode PE1 may have a base portion BA formed on the substrate 101. A first interlayer insulating layer (or first insulating layer) IL1 may be formed on the base portion BA of the first pad electrode PE1. The base portion BA of the second pad electrode PE2 may be formed on the first interlayer insulating layer IL1. A second interlayer insulating layer (or second insulating layer) IL2 may be formed on the base portion BA of the second pad electrode PE2. The base portion BA of the third pad electrode PE3 may be formed on the second interlayer insulating layer IL2. A third interlayer insulating layer (or third insulating layer) IL3 may be formed on the base portion BA of the third pad electrode PE3.

[0170] As described above, the base portions BA of adjacent pad electrodes PE can be formed at different layers separated by an insulating layer. In this way, the base portions BA of adjacent pad electrodes PE can be separated by the insulating layer, thereby preventing or suppressing short circuits between them. In this case, the pad electrodes PE can be arranged closer together, thereby substantially reducing the spacing between the pad electrodes PE.

[0171] Additionally, a first contact hole CH1, serving as a contact hole CH exposing the base portion BA of the first pad electrode PE1, can be formed in the first to third interlayer insulating layers IL1 to IL3 provided on the base portion BA of the first pad electrode PE1. A second contact hole CH2, serving as a contact hole CH exposing the base portion BA of the second pad electrode PE2, can be formed in the second interlayer insulating layers IL2 and IL3 provided on the base portion BA of the second pad electrode PE2. A third contact hole CH3, serving as a contact hole CH exposing the base portion BA of the third pad electrode PE3, can be formed in the third interlayer insulating layer IL3 provided on the base portion BA of the third pad electrode PE3.

[0172] In this way, a contact hole CH can be formed on the base portion BA of each pad electrode PE to expose the base portion BA of each pad electrode PE.

[0173] Within the contact hole CH, a conductive film CL can be formed along the inner surface of the pad recess PH corresponding to each pad electrode PE. For example, the conductive film CL can be formed along the inner surface (i.e., the side surface and the bottom surface) of the corresponding contact hole CH. Therefore, the conductive film CL formed in the pad recess PH can extend along the contact hole CH and connect to the substrate portion BA of each pad electrode PE.

[0174] In this respect, the conductive film CL formed in the pad recess PH corresponding to the first pad electrode PE1 can extend along the inner surface of the first contact hole CH1 and contact the base portion BA of the first pad electrode PE1. The conductive film CL formed in the pad recess PH corresponding to the second pad electrode PE2 can extend along the inner surface of the second contact hole CH2 and contact the base portion BA of the second pad electrode PE2. The conductive film CL formed in the pad recess PH corresponding to the third pad electrode PE3 can extend along the inner surface of the third contact hole CH3 and contact the base portion BA of the third pad electrode PE3.

[0175] As described above, in this embodiment, the combination of the conductive film CL, which is in contact with the inner surfaces of the pad electrode PE and the insulating layers ISL and IL3 and is formed along the pad groove PH, and the pad electrode PE can be generally used as a unit pad electrode. Therefore, the pad electrode PE can be used as a first electrode, the conductive film CL, which is in direct contact with the conductive ball CB, can be used as a second electrode, and the combination of the first electrode and the second electrode can be considered to constitute a pad electrode.

[0176] As described above, according to embodiments of the present invention, a pad recess defined by at least a portion of the pad electrodes can be formed in a unit region where pad electrodes are disposed. In some cases, the pad recess may have an uneven structure, and / or a conductive film may be formed along the pad recess.

[0177] By forming pad recesses corresponding to the pad electrodes as described above, the connection surface of the pad electrodes can be increased. Therefore, the area occupied by the pad electrodes can be reduced, thereby reducing the spacing between the pad electrodes.

[0178] In this case, even if the resolution of the display device increases, the pad electrodes can be arranged with a narrow pitch, so that the pad electrodes can be effectively formed even at high resolution.

[0179] It will be apparent to those skilled in the art that various modifications and variations can be made to the invention without departing from its spirit or scope. Therefore, this invention is intended to cover such modifications and variations, provided they fall within the scope of the appended claims and their equivalents.

Claims

1. A display device, comprising: The display panel includes a plurality of pad electrodes disposed on a pad area of ​​a substrate; as well as A panel driving circuit is attached to the pad area via an anisotropic conductive film containing conductive balls, and the panel driving circuit includes bumps connected to the pad electrodes via a plurality of conductive balls. A pad groove is formed in the unit region where the pad electrodes are provided, defined by at least a portion of the pad electrodes among the plurality of pad electrodes.

2. The display device according to claim 1, further comprising an insulating layer inserted between adjacent pad electrodes among the plurality of pad electrodes.

3. The display device according to claim 1, wherein the pad recess has a shape in which the width of the pad recess is constant in the direction toward the substrate, or the pad recess has a shape in which the width of the pad recess narrows at least at the lower part of the pad recess in the direction toward the substrate.

4. The display device according to claim 1, wherein at least one of the side surface and bottom surface of the pad groove has an uneven shape.

5. The display device of claim 4, wherein the pad electrode includes a protrusion forming the uneven shape of the pad groove, and The protrusion has a shape in which the width of the protrusion is constant or increases from a first end facing the pad groove to a second end opposite to the first end.

6. The display device of claim 1, wherein the pad electrode includes a sidewall portion surrounding the pad recess and a bottom portion below the pad recess.

7. The display device according to claim 6, wherein the height of the sidewall portion is less than the diameter of the conductive ball.

8. The display device according to claim 2, further comprising a conductive film formed along the side and bottom surfaces of the pad groove and in contact with the pad electrode.

9. The display device of claim 8, wherein the pad electrode includes a sidewall portion surrounding the pad recess and a bottom portion below the pad recess. At least one of the sidewall portion and the bottom portion has a groove, and The pad grooves have an uneven shape due to the grooves.

10. The display device of claim 8, wherein the pad electrode includes a bottom portion below the pad recess, and The conductive film is formed along the inner surface of the insulating layer and the upper surface of the bottom portion.

11. The display device of claim 10, wherein the insulating layer includes a bottom located below the pad recess, and The bottom of the insulating layer includes a groove, and the bottom portion of the pad electrode is disposed in the groove.

12. The display device of claim 8, further comprising an interlayer insulating layer located between the substrate and the pad recess and having contact holes formed therein. The pad electrode includes a sidewall portion surrounding the pad recess and a base portion located between the interlayer insulating layer and the substrate, and the pad electrode contacts the conductive film extending along the contact hole.

13. The display device of claim 12, wherein the plurality of pad electrodes arranged in the pad region include a first pad electrode and a second pad electrode. A first interlayer insulating layer is formed on the substrate portion of the first pad electrode. The substrate portion on which the second pad electrode is formed is located on the first interlayer insulating layer. A second interlayer insulating layer is formed on the substrate portion of the second pad electrode. The substrate portion of the first pad electrode contacts the conductive film extending along the first contact hole formed in the first and second interlayer insulating layers, and The substrate portion of the second pad electrode contacts the conductive film extending along the second contact hole formed in the second interlayer insulating layer.

14. The display device of claim 13, wherein the plurality of pad electrodes disposed in the pad region further comprises a third pad electrode. The substrate portion on which the third pad electrode is formed is located on the second interlayer insulating layer. A third interlayer insulating layer is formed on the substrate portion of the third pad electrode. The substrate portion of the first pad electrode contacts the conductive film extending along the first contact hole formed in the first interlayer insulating layer to the third interlayer insulating layer. The substrate portion of the second pad electrode contacts the conductive film extending along the second contact hole formed in the second and third interlayer insulating layers, and The substrate portion of the third pad electrode contacts the conductive film extending along the third contact hole formed in the third interlayer insulating layer.

15. The display device according to claim 8, wherein the conductive film has a thickness less than that of the pad electrode.

16. The display device of claim 9, wherein the sidewall portion of the pad electrode has a first groove, and The insulating layer is exposed to the pad recess through the first recess.

17. The display device of claim 16, wherein the bottom portion of the pad electrode has a second groove, and The substrate is exposed to the pad recess through the second recess.

18. The display device of claim 10, wherein the width of the bottom portion of the pad electrode is less than the width of the pad recess.

19. A display device, comprising: A display panel, the display panel including a display area and a non-display area arranged around the display area; as well as The driving circuit section is used to drive the display panel. The non-display area includes a pad area, and multiple pad electrodes are arranged on the substrate within the pad area. A pad groove is formed in at least one of the plurality of pad electrodes.

20. The display device of claim 19, further comprising a conductive film formed along the side and bottom surfaces of the pad recess and in contact with the pad electrode. An insulating layer is inserted between adjacent pad electrodes, and The pad electrode is located in the bottom portion below the pad recess.

21. The display device of claim 20, wherein the conductive film covers the surface of the substrate and the bottom portion of the pad electrode.

22. The display device of claim 20, wherein the insulating layer includes a bottom located below the pad recess, and The conductive film covers the bottom of the insulating layer and the bottom portion of the pad electrode.

23. The display device of claim 20, wherein the pad electrode further includes a sidewall portion surrounding the pad recess, and The conductive film covers the sidewall portion of the pad recess and the inner surface of the insulating layer.

24. The display device of claim 20, further comprising an interlayer insulating layer located between the substrate and the pad recess. The pad electrode includes a substrate portion disposed in the interlayer insulating layer, and The conductive film contacts the substrate portion of the pad electrode.

Images