Display device

Abstract

A display device is provided. The display device may include: a substrate base including at least one curved region and a non-curved region adjacent to the curved region and having a flexible property; a circuit device layer located on the substrate base, the circuit device layer including thin film transistors; a display device layer located on the circuit device layer, the display device layer including organic light emitting diodes connected to the thin film transistors; a packaging layer covering the display device layer and including a first inorganic layer, an organic layer, and a second inorganic layer stacked in sequence; and a groove overlapping with the curved region, the groove penetrating the display device layer and the circuit device layer, and at least one of the first inorganic layer and the second inorganic layer covering the groove.

Description

[0001] This application claims the priority and benefit of Korean Patent Application No. 10-2019-0168973, filed with the Korean Intellectual Property Office on December 17, 2019, the entire contents of which are incorporated herein by reference. Technical Field

[0002] Aspects of embodiments of the present disclosure relate to a display device. Background Art

[0003] In the information society, display devices are becoming increasingly important as media for providing visual information to users. Examples of display devices include liquid crystal display (LCD) devices, plasma display panel (PDP) devices, organic light emitting diode (OLED) devices, field emission display (FED) devices, and electrophoretic display (EPD) devices.

[0004] When an electrical signal is applied to a display device, the display device is activated. The display device includes a display panel for displaying an image and a touch screen for sensing an external touch event.

[0005] Recently, there has been an increasing demand for flexible display devices that can be bent or folded with a specific curvature. Summary of the Invention

[0006] According to an aspect of embodiments of the present disclosure, there is provided a display device having improved reliability. According to another aspect of embodiments of the present disclosure, there is provided a highly reliable display device that can effectively reduce mechanical stress caused by a bending operation.

[0007] According to one or more embodiments, a display device includes: a substrate base including at least one bending region and a non-bending region adjacent to the bending region, and having a flexible property; a circuit device layer disposed on the substrate base, the circuit device layer including thin film transistors; a display device layer disposed on the circuit device layer, the display device layer including organic light emitting diodes connected to the thin film transistors; a encapsulation layer covering the display device layer and including a first inorganic layer, an organic layer, and a second inorganic layer sequentially stacked; and a groove overlapping with the bending region, the groove penetrating the display device layer and the circuit device layer, and at least one of the first inorganic layer and the second inorganic layer covering the groove.

[0008] In an embodiment, the groove may have an undercut structure.

[0009] In an embodiment, the groove may have a structure in which patterns extending in two different directions are alternately arranged therein.

[0010] In an embodiment, the groove may extend to define a bending pattern or a sine wave pattern in one direction.

[0011] In an embodiment, the groove may include a plurality of groove patterns spaced apart from each other in one direction, and the circuit device layer and the display device layer may be located between the groove patterns.

[0012] In an embodiment, the groove may include a plurality of extension patterns and connection patterns, the plurality of extension patterns extending in a first direction and arranged in a direction intersecting the first direction, and the connection patterns being located between the extension patterns.

[0013] In an embodiment, the groove may include a center pattern and branch patterns, the center pattern extending in a first direction, the branch patterns extending from the center pattern in a direction inclined with respect to the first direction, and being spaced apart from each other in the first direction.

[0014] In an embodiment, the display device may further include another groove spaced farther from the non-bending region than the groove and penetrating the display device layer and the circuit device layer. The another groove may be sequentially covered by a first inorganic layer and a second inorganic layer.

[0015] In an embodiment, the display device may further include a planarization layer filling the another groove, the inner surface of the another groove being closed by the second inorganic layer, and the planarization layer providing a flat surface together with the encapsulation layer.

[0016] In an embodiment, the display device may further include an auxiliary groove spaced farther from the non-bending region than the groove and penetrating the display device layer, the circuit device layer, and a part of the substrate. The auxiliary groove may be sequentially covered by a first inorganic layer and a second inorganic layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Embodiments will be understood more clearly by the following description of some example embodiments in conjunction with the accompanying drawings. The drawings represent some non-limiting example embodiments as described herein.

[0018] Figure 1A is a perspective view showing a first operation of a display device according to an embodiment of the inventive concept.

[0019] Figure 1B is a perspective view showing a second operation of a display device according to an embodiment of the inventive concept.

[0020] Figure 1C is a perspective view showing a third operation of a display device according to an embodiment of the inventive concept.

[0021] Figure 2 is a cross-sectional view showing a display device according to an embodiment of the inventive concept.

[0022] Figure 3A and Figure 3Bis a perspective view showing a display device according to an embodiment of the inventive concept.

[0023] Figure 4 is a perspective view showing a display device according to an embodiment of the inventive concept.

[0024] Figure 5A is a plan view showing a display panel of a display device according to an embodiment of the inventive concept.

[0025] Figure 5B is a cross-sectional view showing a display module of a display device according to an embodiment of the inventive concept.

[0026] Figure 6 is an equivalent circuit diagram showing a pixel of a display device according to an embodiment of the inventive concept.

[0027] Figure 7A is a cross-sectional view showing a display device according to an embodiment of the inventive concept.

[0028] Figure 7B is Figure 7A an enlarged cross-sectional view of the region TT'.

[0029] Figures 8A to 8E is a plan view showing a groove according to some embodiments of the inventive concept.

[0030] Figure 9A is a cross-sectional view showing a display device according to an embodiment of the inventive concept.

[0031] Figure 9B is Figure 9A an enlarged cross-sectional view of the region QQ'.

[0032] Figure 10 is a cross-sectional view showing a display device according to an embodiment of the inventive concept.

[0033] Figure 11 is a cross-sectional view showing a display device according to an embodiment of the inventive concept.

[0034] Figure 12 is a cross-sectional view showing a display device according to an embodiment of the inventive concept.

[0035] Figure 13 is a cross-sectional view showing a display device according to an embodiment of the inventive concept.

[0036] Figure 14 is a cross-sectional view showing a display device according to an embodiment of the inventive concept.

[0037] These drawings are intended to illustrate the general characteristics of the methods, structures, and / or materials used in certain example embodiments and are intended to supplement the written description provided below. However, these drawings may not be to scale and may not precisely reflect the exact structural or performance characteristics of any given embodiment, and should not be construed as limiting or restricting the scope of the values or properties included in the example embodiments. For example, for clarity, the relative thicknesses and positions of components, layers, regions, and / or structural elements may be reduced or exaggerated. The use of like or identical reference numerals in the various drawings is intended to indicate the presence of like or identical elements or features. Detailed Description

[0038] Some example embodiments of the inventive concept will now be described more fully with reference to the drawings, in which some example embodiments are shown. However, the embodiments of the inventive concept may be implemented in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will fully convey the concept of the example embodiments to those of ordinary skill in the art. In the drawings, the thicknesses of layers and regions may be exaggerated for clarity. Like reference numerals in the drawings denote like elements, and thus their repeated description may be omitted.

[0039] It will be understood that when an element is referred to as being "connected" or "coupled" to another element, the element may be directly connected or coupled to the other element, or one or more intermediate elements may be present. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, no intermediate elements are present. Like reference numerals always denote like elements. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Other words used to describe the relationship between elements or layers should be interpreted in a similar manner (e.g., "between" and "directly between," "adjacent" and "directly adjacent," "on" and "directly on").

[0040] It will be understood that although the terms "first," "second," etc. may be used herein to describe various elements, components, regions, layers, and / or parts, these elements, components, regions, layers, and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or part from another element, component, region, layer, or part. Thus, a first element, component, region, layer, or part discussed below may be referred to as a second element, component, region, layer, or part without departing from the teachings of the example embodiments.

[0041] For ease of description, spatial relative terms such as "under", "below", "lower", "above", "upper", etc. may be used herein to describe the relationship of one element or feature shown in the figures to another (other) element or feature. It will be understood that the spatial relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is flipped, the element described as "under" or "below" another element or feature will then be positioned "above" the said other element or feature. Thus, the exemplary term "under" can encompass both an upper and a lower orientation. The device may be otherwise positioned (e.g., rotated 90 degrees or at other orientations), and the spatial relative descriptors used herein will be correspondingly interpreted.

[0042] The terms used herein are for the purpose of describing particular embodiments and are not intended to limit the example embodiments. As used herein, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are also intended to include the plural forms. It will also be understood that the terms "comprises", "comprising", and / or their variants when used herein specify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0043] Some example embodiments of the inventive concept may be described herein with reference to cross-sectional illustrations that are schematic illustrations of idealized embodiments (and intermediate structures) of the example embodiments. As such, variations in the shape of the illustrations due to, for example, manufacturing techniques and / or tolerances are to be expected. Thus, example embodiments of the inventive concept should not be construed as being limited to the particular shapes of regions shown herein, but will include deviations in shapes resulting from, for example, manufacturing.

[0044] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the example embodiments of the inventive concept pertain. It will also be understood that terms, such as those defined in a commonly used dictionary, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and should not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0045] Figure 1A is a perspective view showing a first operation of a display device DD according to an embodiment of the inventive concept; Figure 1B is a perspective view showing a second operation of a display device DD according to an embodiment of the inventive concept; Figure 1C is a perspective view showing a third operation of a display device DD according to an embodiment of the inventive concept; Figure 2It is a cross-sectional view of a display device DD showing an embodiment according to the inventive concept.

[0046] As Figure 1A shown, when the display device DD is in the first operation mode, the display surface IS for displaying the image IM may be parallel to the plane defined by the first direction axis DR1 and the second direction axis DR2. Here, the third direction axis DR3 will be used to indicate the thickness direction of the display device DD (i.e., the direction perpendicular to the display surface IS). The front surface or top surface and the rear surface or bottom surface of each component can be distinguished based on the third direction axis DR3. However, the directions indicated by the first direction axis DR1, the second direction axis DR2, and the third direction axis DR3 may be relative concepts, and in some embodiments, they may be changed to indicate other directions. Here, the first to third directions may be the directions indicated by the first direction axis DR1, the second direction axis DR2, and the third direction axis DR3, respectively, and will be identified with the same reference numerals.

[0047] Figures 1A to 1C An example is shown in which the display device DD (hereinafter, also referred to as the flexible display device DD) is a foldable display device (one of the flexible display devices). However, the inventive concept is not limited to this example, and in an embodiment, the display device DD may be a rollable or bendable display device. In addition, although a flexible display device is described here, the inventive concept is not limited to this example. For example, the display device DD may be provided in the form of a flat rigid display device. In an embodiment, the flexible display device DD may be used for large-sized electronic devices (e.g., televisions and monitors) or small- and medium-sized electronic devices (e.g., mobile phones, tablets, car navigation systems, gaming consoles, and smart watches).

[0048] As Figure 1A shown, the display surface IS of the flexible display device DD may include a plurality of regions. For example, the flexible display device DD may include a display region DD-DA for displaying the image IM and a non-display region DD-NDA adjacent to the display region DD-DA. The non-display region DD-NDA may not be used for displaying an image. Figure 1A A clock window is shown as an example of the image IM. In an embodiment, the display region DD-DA may have a rectangular shape. In an embodiment, the non-display region DD-NDA may be provided to surround the display region DD-DA. However, the inventive concept is not limited to this example, and the shapes of the display region DD-DA and the non-display region DD-NDA may be variously changed.

[0049] As Figures 1A to 1CAs shown, the display device DD may include a plurality of regions defined based on an operation mode. The display device DD may include a curved region BA that can be curved along a bending axis BX parallel to a second direction DR2, and a first non-curved region NBA1 and a second non-curved region NBA2 that are not curved. As Figure 1B As shown, the display device DD may be configured to perform an inward bending operation in which the display surface IS of the first non-curved region NBA1 is placed to face the display surface IS of the second non-curved region NBA2. As Figure 1C As shown, the display device DD may also be configured to perform an outward bending operation in which the display surface IS is exposed to the outside.

[0050] Figures 1A to 1C An example is shown in which the display device DD has a single curved region BA, but the inventive concept is not limited to this example. For example, in an embodiment, the display device DD may include a plurality of curved regions BA. In an embodiment, the display device DD may be configured to only repeat Figure 1A and Figure 1B the operation modes shown. However, the inventive concept is not limited to this example, and the curved region BA may be defined based on the shape of the display device DD manipulated by the user. For example, different from Figure 1B and Figure 1C , the curved region BA may be defined to extend in a first direction DR1 or in a diagonal direction not parallel to both the first direction DR1 and the second direction DR2. The area of the curved region BA may not be fixed and may change according to its radius of curvature.

[0051] Figure 2 A cross-section of the display device DD taken parallel to both the first direction DR1 and the third direction DR3 is shown.

[0052] As Figure 2 As shown, the display device DD may include a protective film PM, a display module DM, an optical member LM, a window WM, a first adhesive member AM1, a second adhesive member AM2, and a third adhesive member AM3. The display module DM may be disposed between the protective film PM and the optical member LM. The optical member LM may be disposed between the display module DM and the window WM. The first adhesive member AM1 may be used to bond the display module DM to the protective film PM, the second adhesive member AM2 may be used to bond the display module DM to the optical member LM, and the third adhesive member AM3 may be used to bond the optical member LM to the window WM. In an embodiment, at least one of the first adhesive member AM1, the second adhesive member AM2, and the third adhesive member AM3 may be omitted.

[0053] The protective film PM can protect the display module DM. The protective film PM can have a first outer surface OS-L and an attachment surface, the first outer surface OS-L being exposed to the outside, and the first adhesive member AM1 being attached to the attachment surface. The protective film PM can prevent or substantially prevent external moisture from entering the display module DM, and can absorb external impacts from the outside.

[0054] In an embodiment, the protective film PM can include a plastic film serving as a base layer. The protective film PM can include a plastic film containing one selected from the group consisting of polyethersulfone (PES), polyacrylate (PA), polyetherimide (PEI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polyarylate (PAR), polyimide (PI), polycarbonate (PC), poly(arylene ether sulfone), and combinations thereof.

[0055] However, the material for the protective film PM is not limited to plastic resins, and in an embodiment, an organic / inorganic composite material can be used for the protective film PM. In an embodiment, the protective film PM can include a porous organic layer having pores and an inorganic material filling the pores of the organic layer. The protective film PM can also include a functional layer formed on the plastic film. The functional layer can include a resin layer. In an embodiment, the functional layer can be formed by a coating method. In an embodiment, the protective film PM can be omitted.

[0056] The window WM can protect the display module DM from external impacts, and can provide an input surface to the user. The window WM can have a second outer surface OS-U exposed to the outside and an attachment surface to which the third adhesive member AM3 is attached. In an embodiment, Figure 1A and Figure 1C the display surface IS shown in

[0057] In an embodiment, the window WM can include a plastic film. In an embodiment, the window WM can have a multilayer structure. For example, the window WM can have a multilayer structure including at least one of a glass substrate, a plastic film, and a plastic substrate. The window WM can also include a border pattern. The multilayer structure can be formed by a continuous process or by an adhesive process using an adhesive layer.

[0058] The optical member LM can reduce the optical reflectance of light incident from the outside. In an embodiment, the optical member LM can include at least one polarizing film. In an embodiment, the optical member LM can also include a retardation film. In certain embodiments, the optical member LM can be omitted.

[0059] The display module DM may include a display panel DP and a sensing sensor TS. In an embodiment, the sensing sensor TS may be directly disposed on the display panel DP. In this specification, the expression "directly disposed on" is used to mean that one layer is continuously formed on another layer without an additional adhesive layer therebetween.

[0060] The following description will relate to an example in which an organic light-emitting display panel is used as the display panel DP (hereinafter, also referred to as the organic light-emitting display panel DP), but the inventive concept is not limited to this example. For example, the display panel DP may be one of a liquid crystal display panel, a plasma display panel, an electrophoretic display panel, a microelectromechanical systems (MEMS) display panel, and an electrowetting display panel.

[0061] The organic light-emitting display panel DP may generate an image IM based on image data input thereto (e.g., see Figure 1A ). The organic light-emitting display panel DP may have a first display surface BS1-L and a second display surface BS1-U that face each other in a thickness direction or a third direction DR3.

[0062] The sensing sensor TS may obtain coordinate information input from the outside. The sensing sensor TS may sense an external input (e.g., sense an external input in a capacitive sensing manner). The external input may include any one of various types of input signals provided from the outside of the display device DD. The external input may be provided to the sensing sensor TS in any one of various forms. For example, the sensing sensor TS may be configured to sense a touch-type external input (such as a user's body or hand) and a non-touch-type external input (such as a decrease in the distance from the display device DD or a hovering event near the display device DD). Additionally, the sensing sensor TS may be configured to sense a change in a physical characteristic (e.g., force, pressure, or light intensity) of the external input, but the inventive concept is not limited to specific embodiments.

[0063] Although not shown, in an embodiment, the display module DM may further include an anti-reflection layer. The anti-reflection layer may include a color filter or a stack of a conductive layer / insulating layer / conductive layer. The anti-reflection layer may absorb light incident from the outside, or may use destructive interference or polarization phenomena to reduce the optical reflectance of the incident light. In some embodiments, the anti-reflection layer may replace the optical member LM.

[0064] In an embodiment, each of the first adhesive member AM1, the second adhesive member AM2, and the third adhesive member AM3 may be formed of an organic adhesive layer (e.g., an optically clear adhesive (OCA) film, an optically clear resin (OCR) film, or a pressure-sensitive adhesive (PSA) film), or may include an organic adhesive layer (e.g., an optically clear adhesive (OCA) film, an optically clear resin (OCR) film, or a pressure-sensitive adhesive (PSA) film). The organic adhesive layer may include an adhesive material such as any one of a polyurethane material, a polyacrylate material, a polyester material, a polyepoxy material, and a polyvinyl acetate material).

[0065] Although not shown, the display device DD may further include a frame structure for supporting the functional layers so as to maintain Figures 1A to 1C the operation mode or shape shown in. The frame structure may include a joining structure or a hinge structure.

[0066] Figure 3A and Figure 3B is a perspective view showing a display device DD-1 according to an embodiment of the inventive concept. Figure 3A The display device DD-1 shown in is in an unfolded state; Figure 3B The display device DD-1 shown in is in a bent state.

[0067] The display device DD-1 may include a bent region BA and a non-bent region NBA. In the present embodiment, the non-display region DD-NDA of the display device DD-1 may be bent. However, the inventive concept is not limited to this example, and in an embodiment, the bent region BA of the display device DD-1 may be changed.

[0068] Unlike Figures 1A to 1C the display device DD of, the display device DD-1 according to the present embodiment may operate in a fixed shape. The display device DD-1 may operate in a bent state, as shown in Figure 3B . The display device DD-1 in the bent state may be fastened to the frame, and the frame having the display device DD-1 may be coupled to the housing of the electronic device.

[0069] The display device DD-1 according to the present embodiment may have the same cross-sectional structure as that shown in Figure 2 . However, the non-bent region NBA and the bent region BA may have different stacking structures. The non-bent region NBA may have the same cross-sectional structure as that shown in Figure 2 , and the bent region BA may have a cross-sectional structure different from that shown in Figure 2 .

[0070] Figure 4 is a perspective view showing a display device DD-2 according to an embodiment of the inventive concept.

[0071] The display device DD-2 may include a non-curved or flat area NBA for displaying a main image in the forward direction and a curved or side area BA for displaying an auxiliary image in the lateral direction. Although not shown, the auxiliary image may include, for example, an icon image that provides information about the meaning of a related application to the user. In the present embodiment, the curved area BA and the non-curved area NBA may be defined as two different areas of the display device DD-2 distinguished based on the shape of the display device DD-2.

[0072] In the present embodiment, the display device DD-2 is shown to include one curved area BA that is curved along one of the edge portions in the edge portion of the non-curved area NBA. However, in an embodiment, the display device DD-2 may include a pair of curved areas that are curved along two opposite edge portions of the non-curved area NBA.

[0073] The curved area BA that is curved from the non-curved area NBA may display the auxiliary image in a direction that is not parallel to any of the first direction DR1, the second direction DR2, and the third direction DR3.

[0074] Figure 5A is a plan view of an organic light emitting display panel DP included in a display device DD according to an embodiment of the inventive concept; Figure 5B is a cross-sectional view of a display module DM included in a display device DD according to an embodiment of the inventive concept.

[0075] As Figure 5A shown, when viewed in a plan view, the organic light emitting display panel DP may include a display area DA and a non-display area NDA. The display area DA and the non-display area NDA of the organic light emitting display panel DP may correspond to the display area DD-DA and the non-display area DD-NDA of the display device DD (e.g., see Figure 1A ), respectively. The structures of the display area DA and the non-display area NDA of the organic light emitting display panel DP may not be the same as the structures of the display area DD-DA and the non-display area DD-NDA of the display device DD (e.g., see Figure 1A ), and may be changed according to the structure or design of the organic light emitting display panel DP.

[0076] The organic light emitting display panel DP may include a plurality of pixels PX. The area to which light from the pixels PX is provided may be defined as the display area DA. In the present embodiment, the non-display area NDA may be defined along the boundary of the display area DA.

[0077] The organic light-emitting display panel DP may include gate lines GL, data lines DL, emission lines EL, control signal lines SL-D, an initialization voltage line SL-Vint, a voltage line SL-VDD, and a pad (or "bond pad") portion PD.

[0078] Each of the gate lines GL may be connected to a corresponding pixel PX in the pixels PX, and each of the data lines DL may be connected to a corresponding pixel PX in the pixels PX. Each of the emission lines EL may be arranged parallel to a corresponding one of the gate lines GL in the gate lines GL. The control signal line SL-D may provide a control signal to the gate driving circuit GDC. The initialization voltage line SL-Vint may provide an initialization voltage to the pixels PX. The voltage line SL-VDD may be connected to a plurality of pixels PX to provide a first voltage to the pixels PX. The voltage line SL-VDD may include a plurality of lines extending in a first direction DR1 and a plurality of lines extending in a second direction DR2.

[0079] In an embodiment, some of the gate lines GL, data lines DL, emission lines EL, control signal lines SL-D, initialization voltage line SL-Vint, and voltage line SL-VDD may be disposed on the same layer, and others may be disposed on another layer.

[0080] The pad portion PD may be connected to the ends of each of the data line DL, control signal line SL-D, initialization voltage line SL-Vint, and voltage line SL-VDD.

[0081] As Figure 5B shown, the organic light-emitting display panel DP may include a substrate layer or substrate SUB, a circuit device layer DP-CL disposed on the substrate layer SUB, a display device layer DP-OLED disposed on the circuit device layer DP-CL, and a thin encapsulation layer or thin film encapsulation layer TFE disposed on the display device layer DP-OLED.

[0082] In an embodiment, the substrate layer SUB may include at least one plastic film. The substrate layer SUB may be a flexible substrate and may include at least one of a plastic substrate, a glass substrate, a metal substrate, and a substrate made of an organic / inorganic composite material. In an embodiment, the plastic substrate may include at least one of an acrylic resin, a methacrylic resin, a polyisoprene resin, a vinyl resin, an epoxy resin, a polyurethane resin, a cellulose resin, a silicone resin, a polyimide resin, a polyamide resin, and a perylene resin.

[0083] The circuit device layer DP-CL may include a plurality of insulating layers, a plurality of conductive layers, and at least one semiconductor layer. The conductive layers of the circuit device layer DP-CL may be used to form the signal lines or control circuits of the pixels PX.

[0084] The display device layer DP - OLED may include an organic light - emitting diode OLED connected to at least one of the conductive layers in the circuit device layer DP - CL (see Figure 6 ).

[0085] In an embodiment, the thin film encapsulation layer TFE may hermetically seal or encapsulate the display device layer DP - OLED. In an embodiment, the thin film encapsulation layer TFE may include at least two inorganic layers and at least one organic layer disposed between the at least two inorganic layers. The inorganic layer may protect the display device layer DP - OLED from moisture or oxygen, and the organic layer may protect the display device layer DP - OLED from contaminants (e.g., dust particles).

[0086] In an embodiment, the sensing sensor TS may be directly disposed on the thin film encapsulation layer TFE. The sensing sensor TS may include a conductive pattern and a sensing signal line. The conductive pattern and the sensing signal line may have a single - layer or multi - layer structure.

[0087] In an embodiment, the conductive pattern and the sensing signal line may be formed of at least one of indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO), PEDOT, metal nanowires, and graphene, or may include at least one of indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO), PEDOT, metal nanowires, and graphene. In an embodiment, the conductive pattern and the sensing signal line may include at least one of metal materials (e.g., molybdenum, silver, titanium, copper, aluminum, and their alloys). The conductive pattern and the sensing signal line may have the same layer structure as each other or different layer structures from each other.

[0088] Figure 6 is an equivalent circuit diagram of a pixel PX included in a display device DD according to an embodiment of the inventive concept.

[0089] In Figure 6 , the i - th pixel PXi is shown as an example of the pixel PX. Here, as shown in Figure 6 , the i - th pixel PXi may be connected to the k - th data line DLk which is one of the data lines DL.

[0090] The i - th pixel PXi may include an organic light - emitting diode OLED and a pixel driving circuit for controlling the organic light - emitting diode OLED. In an embodiment, the pixel driving circuit may include a first thin - film transistor T1 to a seventh thin - film transistor T7 (hereinafter, also referred to as a first transistor T1 to a seventh transistor T7) and a storage capacitor Cst. An example in which the first transistor T1 to the seventh transistor T7 are n - type thin - film transistors will be described below, but the inventive concept is not limited to this example.

[0091] The driving transistor can control the driving current supplied to the organic light-emitting diode OLED. In an embodiment, the driving transistor can be the second transistor T2. The output electrode of the second transistor T2 can be electrically connected to the organic light-emitting diode OLED. The output electrode of the second transistor T2 can be in direct contact with the first electrode or anode of the organic light-emitting diode OLED or can be connected to the anode via another transistor.

[0092] The control transistor can be configured to receive a control signal through its control electrode. The control signal applied to the i-th pixel PXi can include the (i - 1)-th gate signal Si-1, the i-th gate signal Si, the (i + 1)-th gate signal Si+1, the data signal Dk, and the i-th light emission control signal Ei. In some embodiments, the control transistor can include the first transistor T1 and the third transistor T3 to the seventh transistor T7.

[0093] The node between the output electrode of the fourth transistor T4 and the control electrode of the second transistor T2 can be defined as the first node N1, and the node between the seventh transistor T7 and the storage capacitor Cst can be defined as the second node N2.

[0094] The second transistor T2 can include an input electrode that receives the first voltage ELVDD through the fifth transistor T5, an output electrode, and a control electrode coupled to the first node N1. The output electrode of the second transistor T2 can supply the first voltage ELVDD to the organic light-emitting diode OLED through the sixth transistor T6. The input electrode of the second transistor T2 can be coupled to the first node N1 through the third transistor T3. The second transistor T2 can control the driving current supplied to the organic light-emitting diode OLED based on the potential of the first node N1.

[0095] The first transistor T1 can include an input electrode coupled to the k-th data line DLk, a control electrode coupled to the i-th gate line GLi, and an output electrode coupled to the output electrode of the second transistor T2. The first transistor T1 can be turned on by the gate signal applied to the i-th gate line GLi (here, the i-th gate signal Si), and in this case, the data signal Dk applied to the k-th data line DLk can be provided to the storage capacitor Cst. The first transistor T1 can be referred to as a switching transistor.

[0096] The third transistor T3 can include an input electrode coupled to the input electrode of the second transistor T2, a control electrode coupled to the i-th gate line GLi, and an output electrode coupled to the first node N1. The third transistor T3 can be turned on in response to the i-th gate signal Si.

[0097] When the first transistor T1 and the third transistor T3 are turned on, the second transistor T2 can be used as a diode-like element between the first transistor T1 and the third transistor T3. In this case, the first transistor T1 can be coupled to the first node N1 through the second transistor T2 and the third transistor T3.

[0098] The storage capacitor Cst can be disposed between the first node N1 and the first electrode of the organic light-emitting diode OLED and coupled to the first node N1 and the first electrode of the organic light-emitting diode OLED. The storage capacitor Cst can be charged to a voltage level corresponding to the voltage applied to the first node N1.

[0099] The fourth transistor T4 can include an input electrode coupled to the voltage line SL-VDD, a control electrode receiving the (i-1)th gate signal Si-1, and an output electrode coupled to the first node N1. The switching operation of the fourth transistor T4 can be controlled in response to the (i-1)th gate signal Si-1. The control electrode of the fourth transistor T4 can be coupled to the (i-1)th gate line GLi-1. The signal line to which the (i-1)th gate signal Si-1 is applied can be changed to a dummy signal line or the like.

[0100] The fifth transistor T5 can include an input electrode coupled to the voltage line SL-VDD, a control electrode coupled to the ith emission line ELi, and an output electrode coupled to the input electrode of the second transistor T2. The switching operation of the fifth transistor T5 can be controlled in response to the ith emission control signal Ei.

[0101] The sixth transistor T6 can include an input electrode coupled to the output electrode of the second transistor T2, a control electrode coupled to the ith emission line ELi, and an output electrode coupled to the first electrode of the organic light-emitting diode OLED. The switching operation of the sixth transistor T6 can be controlled in response to the ith emission control signal Ei provided through the ith emission line ELi.

[0102] The switching operations of the fifth transistor T5 and the sixth transistor T6 can be controlled to selectively establish a current path between the voltage line SL-VDD and the organic light-emitting diode OLED. In some embodiments, one of the fifth transistor T5 and the sixth transistor T6 can be omitted.

[0103] The seventh transistor T7 can include an input electrode coupled to the initialization voltage line SL-Vint, a control electrode receiving the (i + 1)th gate signal Si+1, and an output electrode coupled to the first electrode of the organic light-emitting diode OLED. The control electrode of the seventh transistor T7 can be coupled to the (i + 1)th gate line GLi+1. The signal line to which the (i + 1)th gate signal Si+1 is applied can be changed to a dummy signal line or the like.

[0104] If the fourth transistor T4 is turned on, the first node N1 can be reset through the first voltage ELVDD. If the seventh transistor T7 is turned on, the second node N2 can be initialized through the initialization voltage Vint. When the seventh transistor T7 is turned on, the first electrode of the organic light-emitting diode OLED can be initialized through the initialization voltage Vint. The potential difference between the second voltage ELVSS applied to the second electrode or the cathode of the organic light-emitting diode OLED and the initialization voltage Vint can be lower than the light-emitting threshold voltage of the organic light-emitting diode OLED.

[0105] Figure 7A is a cross-sectional view showing a display device DD according to an embodiment of the inventive concept; Figure 7B is Figure 7A an enlarged cross-sectional view of the region TT'. Figures 8A to 8E is a plan view showing a groove according to some embodiments of the inventive concept. For simplicity of description, the elements previously described with reference to FIGS. 1 to Figure 6 may be identified by the same reference numerals without repeating their repeated description. In an embodiment, Figure 7A the transistor TR may be configured to have a structure substantially the same as that of Figure 6 the sixth transistor T6.

[0106] The substrate base SUB may include a plurality of regions corresponding to the curved region BA and the non-curved region NBA described with reference to Figures 1A to 4 For example, the substrate base SUB may include a curved region BA and a non-curved region NBA. Figure 7A An example is shown in which the emission pattern EML of the pixel PX is disposed on the non-curved region NBA and spaced apart from the curved region BA, but the inventive concept is not limited to this example. For example, the emission pattern EML may be partially disposed on the curved region BA, and in this case, the curved region BA may also be used to display the image IM.

[0107] The substrate base SUB may include a plastic substrate, a glass substrate, a metal substrate, etc. In an embodiment, the plastic substrate may include at least one of an acrylic resin, a methacrylic resin, a polyisoprene resin, a vinyl resin, an epoxy resin, a polyurethane resin, a cellulose resin, a silicone resin, a polyimide resin, a polyamide resin, and a perylene resin.

[0108] The buffer layer BFL may be disposed on the substrate base SUB. The semiconductor pattern OSP may be disposed on the buffer layer BFL. In an embodiment, the buffer layer BFL may be formed of an inorganic material or may include an inorganic material. Accordingly, the buffer layer BFL may prevent or substantially prevent oxygen or moisture that may pass through the substrate base SUB from entering the pixel PX. In addition, the buffer layer BFL may reduce the surface energy of the substrate base SUB, and in this case, the elements of the pixel PX may be stably formed on the substrate base SUB.

[0109] The transistor TR may be placed on the buffer layer BFL. The transistor TR may include a semiconductor pattern OSP, a control electrode GE, an input electrode DE, and an output electrode SE. The semiconductor pattern OSP may be disposed on the buffer layer BFL. The semiconductor pattern OSP may be formed of a semiconductor material or may include a semiconductor material. For example, the semiconductor pattern OSP may be formed of indium tin oxide (ITO), indium gallium zinc oxide (IGZO), zinc oxide (ZnO), or indium zinc oxide (IZnO), or may include indium tin oxide (ITO), indium gallium zinc oxide (IGZO), zinc oxide (ZnO), or indium zinc oxide (IZnO).

[0110] The control electrode GE may be spaced apart from the semiconductor pattern OSP, and the first insulating layer 10 may be disposed therebetween.

[0111] The input electrode DE and the output electrode SE may be disposed to penetrate the first insulating layer 10 and the second insulating layer 20, and may be respectively coupled to two opposite portions of the semiconductor pattern OSP. In an embodiment, the stacked structure of the transistor TR may be variously changed, and the inventive concept is not limited to the specific structure of the transistor TR.

[0112] The third insulating layer 30 may be disposed on the second insulating layer 20 to cover the input electrode DE and the output electrode SE. The third insulating layer 30 may be formed of at least one of organic materials or at least one of inorganic materials, or may include at least one of organic materials or at least one of inorganic materials, and may have a single-layer or stacked structure.

[0113] The first electrode AE may be disposed on the third insulating layer 30. The first electrode AE may be disposed to penetrate the third insulating layer 30 and may be electrically connected to the transistor TR. Figure 7A An example in which the first electrode AE is separated from the transistor TR is shown, but the first electrode AE may be connected to the transistor TR through a contact hole penetrating the third insulating layer 30.

[0114] The pixel defining layer PDL may be disposed on the third insulating layer 30. An opening OP may be defined in the pixel defining layer PDL to penetrate the pixel defining layer PDL. The opening OP may expose at least a portion of the first electrode AE. The pixel defining layer PDL may be formed of an organic material or may include an organic material. The opening OP may correspond to a light emitting region of the pixel PX.

[0115] An emission pattern EML may be disposed on the first electrode AE exposed by the opening OP. The emission pattern EML may include a light emitting material. For example, the emission pattern EML may include at least one of materials capable of emitting red, green, and blue light. In an embodiment, the emission pattern EML may be formed of a fluorescent or phosphorescent material or may include a fluorescent or phosphorescent material. The emission pattern EML may be formed of at least one of organic light emitting materials or at least one of inorganic light emitting materials or may include at least one of organic light emitting materials or at least one of inorganic light emitting materials. The emission pattern EML may emit light in response to a potential difference between two electrodes (e.g., the first electrode AE and the second electrode CE) of the organic light emitting diode OLED.

[0116] The second electrode CE may be disposed on the emission pattern EML. In an embodiment, the second electrode CE may be formed of a transparent conductive material or a semi-transparent and semi-reflective conductive material or may include a transparent conductive material or a semi-transparent and semi-reflective conductive material. Accordingly, light generated by the emission pattern EML may easily pass through the second electrode CE and may propagate in a third direction DR3. In an embodiment, the second electrode CE may be commonly disposed in a plurality of pixels PX.

[0117] However, the inventive concept is not limited to this example, and in an embodiment, the organic light emitting diode OLED may be designed to have a backside emission structure in which the first electrode AE includes a transparent or semi-transparent and semi-reflective material or a double-sided emission structure in which light is emitted through both its front surface and back surface.

[0118] The organic light emitting diode OLED may include at least one of a hole control layer HCL disposed between the first electrode AE and the emission pattern EML and an electron control layer ECL disposed between the emission pattern EML and the second electrode CE, but the inventive concept is not limited to this example or specific embodiments.

[0119] A thin encapsulation layer TFE may cover the organic light emitting diode OLED. In the present embodiment, the thin encapsulation layer TFE may include a first inorganic layer LIL, an organic layer OEL, and a second inorganic layer UIL sequentially stacked in a third direction DR3.

[0120] The first inorganic layer LIL may cover the second electrode CE. The first inorganic layer LIL may prevent or substantially prevent external moisture or oxygen from entering the organic light-emitting diode OLED. In an embodiment, the first inorganic layer LIL may be formed of at least one of, for example, silicon nitride, silicon oxide, and a mixture thereof, or may include at least one of, for example, silicon nitride, silicon oxide, and a mixture thereof. In an embodiment, the first inorganic layer LIL may be formed by a chemical vapor deposition process.

[0121] The organic layer OEL may be disposed on the first inorganic layer LIL to be in contact with the first inorganic layer LIL. The organic layer OEL on the first inorganic layer LIL may be disposed to have a flat surface. The organic layer OEL may cover uneven structures, particles, etc. present on the first inorganic layer LIL, and thus, may be able to prevent or substantially prevent elements formed on the organic layer OEL from being affected by the surface state of the top surface of the first inorganic layer LIL. In addition, the organic layer OEL may relieve stress between layers in contact with each other. In an embodiment, the organic layer OEL may be formed of or include an organic material, and may be formed by a solution process (e.g., a spin coating process, a slot coating process, and an inkjet process).

[0122] The second inorganic layer UIL may be disposed on the organic layer OEL to cover the organic layer OEL. Since the organic layer OEL has a relatively flat top surface, the second inorganic layer UIL may be formed more stably on the organic layer OEL compared to a case where the second inorganic layer UIL is directly formed on the first inorganic layer LIL. The second inorganic layer UIL may encapsulate the organic layer OEL, and may prevent or substantially prevent moisture from leaking from the organic layer OEL to the outside. In an embodiment, the second inorganic layer UIL may be formed of at least one of, for example, silicon nitride, silicon oxide, and a mixture thereof, or may include at least one of, for example, silicon nitride, silicon oxide, and a mixture thereof. In an embodiment, the second inorganic layer UIL may be formed by a chemical vapor deposition process.

[0123] In the present embodiment, the structure from the buffer layer BFL to the third insulating layer 30 may be defined as Figure 5B the circuit device layer DP-CL shown in, and the structure including the pixel defining layer PDL and the organic light-emitting diode OLED may be defined as the display device layer DP-OLED.

[0124] In the present embodiment, the first inorganic layer LIL and the second inorganic layer UIL of the thin encapsulation layer TFE may extend from the non-bending area NBA to the bending area BA. In an embodiment, for example, the first inorganic layer LIL and the second inorganic layer UIL may be disposed to cover the entire top surface of the substrate base SUB.

[0125] In an embodiment, the display device DD may include a groove BR that overlaps with the bending region BA and is configured to penetrate some elements of the display device DD. In an embodiment, for example, the groove BR may be configured to penetrate the display device layer DP-OLED and the circuit device layer DP-CL and expose a part of the substrate base SUB.

[0126] The groove BR may have an inner surface BR-I covered by the first inorganic layer LIL. The groove BR having the first inorganic layer LIL may be filled with the organic layer OEL of the thin encapsulation layer TFE.

[0127] Referring to Figure 7B , the groove BR according to an embodiment may include a first hole GH1 that penetrates the insulating layers BFL, 10, 20, and 30 of the circuit device layer DP-CL. Additionally, the groove BR may further include a second hole GH2 that overlaps with the first hole GH1 and is configured to penetrate the pixel defining layer PDL and the first electrode AE of the display device layer DP-OLED.

[0128] In an embodiment, the first hole GH1 and the second hole GH2 may have different widths from each other in a specific direction. For example, in a specific direction, the minimum width W2 of the second hole GH2 may be smaller than the minimum width W1 of the first hole GH1. In this case, the groove BR may have an undercut structure.

[0129] In an embodiment, the undercut structure may be caused by a difference in the etching rate between the insulating layers BFL, 10, 20, and 30 of the circuit device layer DP-CL and the pixel defining layer PDL and the first electrode AE of the display device layer DP-OLED.

[0130] In the present embodiment, the pixel defining layer PDL and the first electrode AE near the first hole GH1 may be defined as a tip portion TP. According to an embodiment of the inventive concept, since the tip portion TP is covered by one of the inorganic layers LIL and UIL of the thin encapsulation layer TFE, and the inner surface BR-I of the groove BR is covered by the organic layer OEL of the thin encapsulation layer TFE, the structural stability of the groove BR can be improved.

[0131] Figure 7A The groove BR and the grooves to be described below may be configured to have substantially the same features as the grooves described with reference to Figures 8A to 8E . Figures 8A to 8E Each of the grooves may have an inner surface BR-I covered by one of the inorganic layers LIL and UIL of the thin encapsulation layer TFE. Figures 8A to 8E Each of Figure 7A shows the shape of the groove BR when viewed, for example, in a plan view.

[0132] Referring toFigure 8A According to an embodiment, the groove BR-A may include a first pattern B1 and a second pattern B2 that linearly extend in two different directions. In the embodiment, the first pattern B1 and the second pattern B2 may be alternately arranged and may be connected to each other. For example, the groove BR-A may be provided to have a zigzag shape.

[0133] Refer to Figure 8B According to an embodiment, the groove BR-B may extend to form a curved pattern or a sine wave pattern in a specific direction. For example, when viewed based on its side surface, the groove BR-B may include convex portions and concave portions.

[0134] Refer to Figure 8C According to an embodiment, the groove BR-C may include a plurality of groove patterns B3, B4 to Bn that are spaced apart from each other in a specific direction. The circuit device layer DP-CL and the display device layer DP-OLED may be disposed between the groove patterns B3, B4 to Bn. In other words, the circuit device layer DP-CL and the display device layer DP-OLED that are not pierced by the groove patterns B3, B4, and Bn may remain between the groove patterns B3, B4 to Bn.

[0135] Refer to Figure 8D According to an embodiment, the groove BR-D may include a plurality of extension patterns B5 and a plurality of connection patterns B6. The extension patterns B5 may extend in a specific direction and may be arranged to be spaced apart from each other in a direction crossing the specific direction. The connection patterns B6 may be disposed between the extension patterns B5 to connect the extension patterns B5 to each other.

[0136] Refer to Figure 8E According to an embodiment, the groove BR-E may include a center pattern B7 and branch patterns B8. The center pattern B7 may extend in a specific direction. The branch patterns B8 may extend in a direction inclined with respect to the specific direction and may be arranged to be spaced apart from each other in the specific direction. The branch patterns B8 may be connected to the center pattern B7.

[0137] According to some embodiments of the inventive concept, since the groove BR superimposed on the bending region BA is provided to have one of the shapes described with reference to Figures 8A to 8E it is possible to reduce the stress that may be caused when the display device DD is bent. Accordingly, a display device DD having improved bending durability may be provided.

[0138] In an embodiment, a liquid organic material may be supplied to form an organic layer OEL of a thin encapsulation layer TFE, and during this process, a groove BR may define a spreading boundary of the liquid organic material to be spread. For example, the thin encapsulation layer TFE may be formed by coating a first inorganic layer LIL with a liquid organic material using an inkjet method, and in this case, the groove BR may define a boundary of an area to be coated with the liquid organic material and may prevent or substantially prevent the liquid organic material from spilling out of the groove BR.

[0139] Figure 9A is a cross-sectional view showing a display device DD-A according to an embodiment of the inventive concept; Figure 9B is Figure 9A an enlarged cross-sectional view of the area QQ'. Figure 10 is a cross-sectional view showing a display device DD-B according to an embodiment of the inventive concept. Figure 11 is a cross-sectional view showing a display device DD-C according to an embodiment of the inventive concept. For simplicity of description, the elements previously described with reference to FIGS. 1 to Figure 8E may be identified by the same reference numerals without repeating their repeated description.

[0140] In some embodiments, the display device DD-A, DD-B, or DD-C may include a substrate base SUB including a bending area BA and a non-bending area NBA, a circuit device layer DP-CL, a display device layer DP-OLED, a thin encapsulation layer TFE, pixels PX, and at least one groove on the bending area BA.

[0141] The circuit device layer DP-CL may include a plurality of insulating layers BFL, 10, 20, and 30 and transistors TR, and the transistors TR may include a semiconductor pattern OSP, a control electrode GE, an input electrode DE, and an output electrode SE disposed between the insulating layers BFL, 10, 20, and 30. The display device layer DP-OLED may include a pixel defining layer PDL in which an opening OP is defined and an organic light-emitting diode OLED including a first electrode AE, a hole control layer HCL, an emission pattern EML, an electron control layer ECL, and a second electrode CE. The thin encapsulation layer TFE may include a first inorganic layer LIL, an organic layer OEL, and a second inorganic layer UIL stacked in sequence.

[0142] Referring to Figure 9A , the display device DD-A according to an embodiment may include a plurality of grooves BR-1 and BR-2 disposed on the bending area BA.

[0143] The inner surface BR-I1 of the groove BR-1 and the groove BR-1 may be the same as that with reference to Figure 7A and Figure 7BElements corresponding to the described groove BR and the inner surface BR-I of the groove BR. Compared with the groove BR-1, the additional groove BR-2 according to the present embodiment can be spaced farther from the non-bending region NBA. The additional groove BR-2 can be provided to penetrate not only the display device layer DP-OLED but also the circuit device layer DP-CL, and can be provided to expose a part of the substrate base SUB.

[0144] The additional groove BR-2 can have an inner surface BR-I2, and the inner surface BR-I2 is sequentially covered by the first inorganic layer LIL and the second inorganic layer UIL.

[0145] Referring to Figure 9B , the additional groove BR-2 can include a third hole GH3 that penetrates the insulating layers BFL, 10, 20, and 30 of the circuit device layer DP-CL. Additionally, the additional groove BR-2 can further include a fourth hole GH4, which is stacked with the third hole GH3 and is provided to penetrate the pixel defining layer PDL and the first electrode AE of the display device layer DP-OLED.

[0146] In an embodiment, the third hole GH3 and the fourth hole GH4 can have different widths from each other in a specific direction. For example, in a specific direction, the minimum width W4 of the fourth hole GH4 can be smaller than the minimum width W3 of the third hole GH3. In this case, the additional groove BR-2 can have an undercut structure.

[0147] In an embodiment, the undercut structure can be caused by the difference in etching rates between the insulating layers BFL, 10, 20, and 30 of the circuit device layer DP-CL and the pixel defining layer PDL and the first electrode AE of the display device layer DP-OLED.

[0148] In the present embodiment, the pixel defining layer PDL and the first electrode AE near the third hole GH3 can be defined as the tip portion TP. In an embodiment, the tip portion TP can be covered by the inorganic layers LIL and UIL of the thin encapsulation layer TFE.

[0149] Returning to the reference Figure 9A , the display device DD-A according to the present embodiment can further include a planarization layer YOC that covers the additional groove BR-2 and a conformal inorganic layer YIL that covers the planarization layer YOC and the thin encapsulation layer TFE. The inner surface BR-I2 of the additional groove BR-2 can be covered by the planarization layer YOC. Therefore, a robust structure of the additional groove BR-2 can be achieved.

[0150] In addition, when viewed in a plan view, each of the groove BR-1 and the additional groove BR-2 can have the same as Figures 8A to 8Ea shape identical to that of a groove therein. Here, the groove BR-1 and the additional groove BR-2 may have the same shape as each other or may have different shapes from each other, but the inventive concept is not limited to this example or specific embodiment.

[0151] According to one or more embodiments of the inventive concept, since the grooves BR-1 and BR-2 that overlap with the bending region BA are provided, it is possible to reduce the stress that may be caused when the display device DD-A is bent. Accordingly, a display device DD-A having improved bending durability may be provided.

[0152] Referring Figure 10 , the display device DD-B according to an embodiment may include a plurality of grooves BR and BR-O provided in the bending region BA.

[0153] The inner surface BR-I of the groove BR and the groove BR may be an element corresponding to the inner surface BR-I of the groove BR and the groove BR described with reference to Figure 7A and Figure 7B . Compared with the groove BR, the auxiliary groove BR-O according to the present embodiment may be spaced farther from the non-bending region NBA. The auxiliary groove BR-O may be formed by removing not only a display device layer DP-OLED and a circuit device layer DP-CL but also a part of a substrate base SUB.

[0154] The auxiliary groove BR-O may have an inner surface that is sequentially covered with a first inorganic layer LIL and a second inorganic layer UIL. In an embodiment, the auxiliary groove BR-O may also have an undercut structure formed due to a difference in etching rate between the etched elements of the circuit device layer DP-CL and the substrate base SUB in the process of forming the auxiliary groove BR-O.

[0155] The display device DD-B according to the present embodiment may further include a planarization layer YOC covering the auxiliary groove BR-O and a conformal inorganic layer YIL covering the planarization layer YOC and a thin encapsulation layer TFE. The inner surface of the auxiliary groove BR-O may be covered with the planarization layer YOC. Accordingly, a robust structure of the auxiliary groove BR-O may be achieved.

[0156] According to one or more embodiments of the inventive concept, since the grooves BR and BR-O that overlap with the bending region BA are provided, it is possible to reduce the stress that may be caused when the display device DD-B is bent. In addition, it is possible to prevent or substantially prevent moisture and oxygen from entering the organic light-emitting diode OLED through or from the bending region BA, thereby improving the reliability of the organic light-emitting diode OLED.

[0157] Figure 10An example in which a plurality of auxiliary grooves BR-O are provided is shown, but in some embodiments, a single auxiliary groove BR-O or two or more auxiliary grooves BR-O may be provided in the display device DD-B. However, the inventive concept is not limited to these examples.

[0158] Referring to Figure 11 , the display device DD-C according to an embodiment may include a sensing sensor TS directly disposed on the thin encapsulation layer TFE. The sensing sensor TS may be an element corresponding to the sensing sensor TS described with reference to Figure 2 .

[0159] In an embodiment, the sensing sensor TS may include a plurality of conductive patterns TML1 and TML2, a plurality of sensing insulating layers TIL1 and TIL2, and a sensing signal line (not shown). The sensing signal line may be disposed in the bending region BA, may extend to the non-bending region NBA, and may be connected to the conductive patterns TML1 and TML2.

[0160] In an embodiment, a first sensing pattern TML1, which is one of the conductive patterns TML1 and TML2, may be directly disposed on the thin encapsulation layer TFE. In an embodiment, the first sensing pattern TML1 may be an element formed on the thin encapsulation layer TFE in a continuous manner without an additional adhesive layer.

[0161] A first sensing insulating layer TIL1, which is one of the sensing insulating layers TIL1 and TIL2, may cover the first sensing pattern TML1. The first sensing insulating layer TIL1 may be formed of at least one of inorganic materials or at least one of organic materials, or may include at least one of inorganic materials or at least one of organic materials.

[0162] A second sensing pattern TML2, which is one of the conductive patterns TML1 and TML2, may be disposed on the first sensing insulating layer TIL1. Accordingly, the first sensing pattern TML1 and the second sensing pattern TML2 may be disposed on different layers, and the first sensing insulating layer TIL1 may be disposed between the first sensing pattern TML1 and the second sensing pattern TML2. A part of the second sensing pattern TML2 may be disposed to penetrate the first sensing insulating layer TIL1 and may be connected to the first sensing pattern TML1.

[0163] A second sensing insulating layer TIL2, which is one of the sensing insulating layers TIL1 and TIL2, may cover the second sensing pattern TML2. The second sensing insulating layer TIL2 may be formed of at least one of inorganic materials or at least one of organic materials, or may include at least one of inorganic materials or at least one of organic materials.

[0164] The conductive patterns TML1 and TML2 may be portions of the sensing electrodes that are spaced apart from each other and configured to sense an external input in a capacitive sensing manner. The conductive patterns TML1 and TML2 may be disposed to be spaced apart from the opening OP of the pixel defining layer PDL.

[0165] Figure 12 is a cross-sectional view showing a display device DD-D according to an embodiment of the inventive concept. Figure 13 is a cross-sectional view showing a display device DD-E according to an embodiment of the inventive concept. Figure 14 is a cross-sectional view showing a display device DD-F according to an embodiment of the inventive concept. For simplicity of description, the elements described with reference to FIGS. 1 to Figure 8E described may be denoted by the same reference numerals without repeating their repeated description.

[0166] Referring to Figure 12 , a display device DD-D according to an embodiment of the inventive concept may include grooves BR-A and BR-B that overlap with one of additional electrodes CL1 and CL2 extending from a non-bending region NBA to a bending region BA.

[0167] A first additional electrode CL1, which is one of the additional electrodes CL1 and CL2, may be disposed on the first insulating layer 10. A second additional electrode CL2, which is one of the additional electrodes CL1 and CL2, may be disposed on the first additional electrode CL1 and may be in contact with the first additional electrode CL1. Additionally, the second additional electrode CL2 may expose a portion of the first additional electrode CL1. The additional electrodes CL1 and CL2 may be used to transfer a second voltage ELVSS described with reference to Figure 6 described. In addition, although not shown, an end portion of at least one of the additional electrodes CL1 and CL2 may be connected to a storage capacitor Cst.

[0168] In the present embodiment, the grooves BR-A and BR-B may overlap with the first additional electrode CL1 and may be spaced apart from the second additional electrode CL2. For example, each of the grooves BR-A and BR-B may be disposed to penetrate the pixel defining layer PDL, the first electrode AE, the third insulating layer 30, and the second insulating layer 20, and may be disposed to expose a portion of the first additional electrode CL1. In an embodiment, when the grooves BR-A and BR-B are formed, the insulating layers BFL and 10 disposed under the first additional electrode CL1 may not be penetrated by the grooves BR-A and BR-B and may extend from the non-bending region NBA to the bending region BA.

[0169] However, the inventive concept is not limited to this example or specific embodiment. For example, in an embodiment, the second additional electrode CL2 may extend to and overlap with the first groove BR-A or may be omitted.

[0170] The first groove BR-A may be closer to the non-bending area NBA than the second groove BR-B. The first groove BR-A may have an inner surface covered by the first inorganic layer LIL of the thin encapsulation layer TFE. The second groove BR-B may have an inner surface covered by the first inorganic layer LIL and the second inorganic layer UIL of the thin encapsulation layer TFE.

[0171] In the present embodiment, the inner surface of the first groove BR-A may be covered by the organic layer OEL of the thin encapsulation layer TFE, and thus, a robust structure of the groove BR-A may be achieved.

[0172] Referring to Figure 13 , a display device DD-E according to an embodiment of the inventive concept may include grooves BR-C and BR-D stacked with additional electrodes CL1 and CL2-A extending from the non-bending area NBA to the bending area BA.

[0173] The first additional electrode CL1 may be disposed on the first insulating layer 10. The second additional electrode CL2-A may be disposed on the first additional electrode CL1 and may be in contact with the first additional electrode CL1. The additional electrodes CL1 and CL2-A may be used to transfer the second voltage ELVSS described in Figure 6 . In addition, an end portion of at least one of the additional electrodes CL1 and CL2-A may be connected to the storage capacitor Cst.

[0174] In the present embodiment, the grooves BR-C and BR-D may be stacked with the additional electrodes CL1 and CL2-A. For example, the grooves BR-C and BR-D may be formed to penetrate the pixel defining layer PDL, the first electrode AE, the third insulating layer 30, and the second insulating layer 20, and may be formed to expose a part of the second additional electrode CL2-A. In an embodiment, when the grooves BR-C and BR-D are formed, the insulating layers BFL and 10 disposed under the second additional electrode CL2-A may not be penetrated by the grooves BR-C and BR-D and may extend from the non-bending area NBA to the bending area BA.

[0175] The first groove BR-C may be closer to the non-bending area NBA than the second groove BR-D. The first groove BR-C may have an inner surface covered by the first inorganic layer LIL of the thin encapsulation layer TFE. The second groove BR-D may have an inner surface covered by the first inorganic layer LIL and the second inorganic layer UIL of the thin encapsulation layer TFE.

[0176] In the present embodiment, the inner surface of the first groove BR-C may be covered by the organic layer OEL of the thin encapsulation layer TFE, and thus, a robust structure of the groove BR-C may be achieved.

[0177] Referring to Figure 14, a display device DD-F according to an embodiment of the inventive concept may include grooves BR-C and BR-D1 stacked with additional electrodes CL1 and CL2-A extending from a non-bending region NBA to a bending region BA.

[0178] In an embodiment, the display device DD-F may further include a planarization layer YOC covering an inner surface of the second groove BR-D1 and a conformal inorganic layer YIL covering the planarization layer YOC and the thin encapsulation layer TFE. The inner surface of the second groove BR-D1 may be covered by the planarization layer YOC. Accordingly, a robust structure of the second groove BR-D1 may be enabled.

[0179] In the present embodiment, the grooves BR-C and BR-D1 are shown as being stacked with each of the additional electrodes CL1 and CL2-A, but the inventive concept is not limited to this example or specific embodiment. For example, the first additional electrode CL1 may be spaced apart from the second groove BR-D1 and may be stacked only with the first groove BR-C, and in some embodiments, the second additional electrode CL2-A may be omitted.

[0180] According to one or more embodiments of the inventive concept, a display device may include grooves stacked with a bending region, and in such a case, the grooves may relieve stress that may be caused when the display device is bent. Accordingly, a display device having improved bending durability may be provided.

[0181] Although some example embodiments of the inventive concept have been specifically shown and described, those of ordinary skill in the art will understand that changes in form and detail may be made therein without departing from the spirit and scope of the appended claims.

Claims

1. A display device, the display device comprising: a substrate base including at least one curved region and a non-curved region adjacent to the at least one curved region, and having a flexible property; a circuit device layer located on the substrate base, the circuit device layer including thin film transistors; a display device layer located on the circuit device layer, the display device layer including organic light emitting diodes connected to the thin film transistors; a packaging layer covering the display device layer, and including a first inorganic layer, an organic layer, and a second inorganic layer stacked in sequence; and a groove superposed on the at least one curved region, the groove penetrating the display device layer and the circuit device layer, and having an undercut structure, wherein at least one of the first inorganic layer and the second inorganic layer covers the groove.

2. The display device according to claim 1, wherein the groove has a structure in which patterns extending in two different directions are alternately arranged therein.

3. The display device according to claim 1, wherein the groove extends to define a curved pattern or a sine wave pattern in one direction.

4. The display device according to claim 1, wherein the groove includes a plurality of groove patterns spaced apart from each other in one direction, and the circuit device layer and the display device layer are located between the plurality of groove patterns.

5. The display device according to claim 1, wherein the groove includes a plurality of extending patterns and connecting patterns, the plurality of extending patterns extend in a first direction and are arranged in a direction crossing the first direction, and the connecting patterns are located between the plurality of extending patterns.

6. The display device according to claim 1, wherein the groove includes a center pattern and branch patterns, the center pattern extends in a first direction, the branch patterns extend from the center pattern in a direction inclined to the first direction, and are spaced apart from each other in the first direction.

7. The display device according to claim 1, the display device further includes another groove, the another groove is spaced farther from the non-curved region than the groove, and penetrates the display device layer and the circuit device layer, wherein the another groove is sequentially covered by the first inorganic layer and the second inorganic layer.

8. The display device according to claim 7, the display device further includes a planarization layer, the planarization layer fills the another groove, an inner surface of the another groove is closed by the second inorganic layer, and the planarization layer provides a flat surface together with the packaging layer.

9. The display device according to claim 1, the display device further includes an auxiliary groove, the auxiliary groove is spaced farther from the non-curved region than the groove, and penetrates the display device layer, the circuit device layer, and a part of the substrate base, wherein the auxiliary groove is sequentially covered by the first inorganic layer and the second inorganic layer.

Images