Display device

Abstract

A display device includes: a substrate including a display area in which a plurality of pixels are defined, and a non-display area that does not overlap with the display area; a plurality of light emitting elements each including a first electrode, an emission layer, and a second electrode sequentially laminated on the substrate and in the display area; and a bank disposed on the substrate and covering an end point of the first electrode. At least a portion of the bank includes: a first bank layer in contact with an end point of the first electrode; a second bank layer disposed in contact with an outer portion of the first bank layer; and a third bank layer disposed on the second bank layer. The second bank layer is surrounded by at least one of the first bank layer and the third bank layer.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10 - 2023 - 0197551, filed with the Korean Intellectual Property Office on December 29, 2023, the disclosure of which is incorporated herein by reference. Technical field

[0003] The present disclosure relates to a display device, and in particular, to a display device capable of enhancing the reliability of a light - emitting element. Background art

[0004] As the information age has arrived, the field of display devices that visually express electrical information signals has developed rapidly. In addition, research has continued to improve the performance of various display devices, such as reduced thickness, weight reduction, and low power consumption.

[0005] Examples of such display devices may include a liquid crystal display (LCD), a field emission display (FED), an electro - wetting display (EWD), and an organic light - emitting display (OLED).

[0006] Among various light - emitting display devices, an electroluminescent display device is a self - emitting display device, so that, unlike an LCD, it does not require a separate light source. Therefore, an electroluminescent display device can be manufactured to have a light weight and a reduced thickness.

[0007] Since an electroluminescent display device is driven at a low voltage, it is not only advantageous in terms of power consumption, but also in terms of color realization, response speed, viewing angle, and contrast ratio (CR). Therefore, it is desirable to use electroluminescent display devices in various fields. Summary of the invention

[0008] An object to be achieved by the present disclosure is to provide a display device that improves the reliability of a light - emitting element by suppressing oxidation and contamination of the surface of an electrode in the light - emitting element.

[0009] Another object to be achieved by the present disclosure is to provide a light - emitting display device having a low - reflection structure for a light - emitting element.

[0010] The objects of the present disclosure are not limited to the above - mentioned objects, and other objects not mentioned above will be clearly understood by those skilled in the art from the following description.

[0011] The objects of the exemplary embodiments of the present disclosure are not limited to the above - mentioned objects, and other objects not mentioned above will be clearly understood by those skilled in the art from the following description.

[0012] A display device according to an exemplary embodiment of the present disclosure includes: a substrate including a display area in which a plurality of pixels are defined and a non-display area that does not overlap with the display area; a plurality of light-emitting elements, each of the plurality of light-emitting elements including a first electrode, an emission layer, and a second electrode that are sequentially stacked on the substrate and in the display area; and a bank disposed on the substrate and covering an end point of the first electrode. At least a part of the bank includes: a first bank layer that contacts the end point of the first electrode and includes an inner part and an outer part in a direction toward the first electrode based on a vertical line passing through a maximum height part of the first bank layer; a second bank layer disposed to contact the outer part of the first bank layer; and a third bank layer disposed on the second bank layer. The second bank layer is surrounded by at least one of the first bank layer and the third bank layer.

[0013] A display device according to another exemplary embodiment of the present disclosure includes: a substrate including a display area in which a plurality of pixels are defined; a plurality of light-emitting elements, each of the plurality of light-emitting elements including a first electrode, an emission layer, and a second electrode that are sequentially stacked on the substrate and in the display area; and a bank disposed on the substrate and partially overlapping with the first electrode, wherein at least a part of the bank includes: a first bank layer that partially overlaps with the first electrode; a second bank layer disposed to partially overlap with the first bank layer and not overlap with the first electrode; and a third bank layer disposed on the second bank layer, and wherein the second bank layer is surrounded by at least one of the first bank layer and the third bank layer.

[0014] Other detailed matters of the exemplary embodiments are included in the detailed description and the drawings.

[0015] The display device according to the exemplary embodiment of the present disclosure can improve reliability by suppressing oxidation and contamination of the surface of the electrode in the light-emitting element.

[0016] According to the exemplary embodiment of the present disclosure, the slope of the bank adjacent to the emission area of the sub-pixel can be selectively adjusted. Accordingly, a low-reflection structure of the light-emitting element can be ensured, and excessive light leakage current flowing to the boundary between the light-emitting elements can also be suppressed.

[0017] As described above, according to the exemplary embodiment of the present disclosure, the potential probability of defects, such as contamination or oxidation, of the display device can be minimized. Accordingly, the lifespan of the display device can be improved, and thus production energy can be reduced, thereby achieving low-power driving.

[0018] The effects of the present disclosure are not limited to the above effects, and it is apparent that those of ordinary skill in the art will understand other effects not mentioned above from the following description.

[0019] The objects to be achieved by the present disclosure, the means for achieving the objects, and the effects of the present disclosure described above do not specify the essential features of the claims, and thus, the scope of the claims is not limited to the disclosure of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and other aspects, features, and other advantages of the present disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0021] Figure 1 is a block diagram of a display device according to an exemplary embodiment of the present disclosure;

[0022] Figure 2 is a plan view of a display device according to an exemplary embodiment of the present disclosure;

[0023] Figure 3 is a cross-sectional view taken along line I-I' of Figure 2 and shows a sub-pixel provided in a display area of a display device according to an exemplary embodiment of the present disclosure;

[0024] Figures 4A to 4G is a cross-sectional view for explaining a process of forming a bank according to an exemplary embodiment of the present disclosure;

[0025] Figure 5A and Figure 5B are cross-sectional views for explaining an example of a process of removing some layers of a bank according to an exemplary embodiment of the present disclosure;

[0026] Figure 6A and Figure 6B are cross-sectional views for explaining another example of a process of removing some layers of a bank according to an exemplary embodiment of the present disclosure;

[0027] Figure 7 is a cross-sectional view showing an example of the shape of a bank according to an exemplary embodiment of the present disclosure;

[0028] Figure 8 is a cross-sectional view showing another example of the shape of a bank according to an exemplary embodiment of the present disclosure;

[0029] Figure 9 is a cross-sectional view showing still another example of the shape of a bank according to an exemplary embodiment of the present disclosure;

[0030] Figure 10 is a cross-sectional view showing still another example of the shape of a bank according to an exemplary embodiment of the present disclosure;

[0031] Figure 11It is a cross-sectional view showing another example of the shape of a dike according to an exemplary embodiment of the present disclosure;

[0032] Figure 12 It is a cross-sectional view showing another example of the shape of a dike according to an exemplary embodiment of the present disclosure;

[0033] Figure 13 It is a cross-sectional view showing an example of the shape of a dike according to another exemplary embodiment of the present disclosure;

[0034] Figure 14 It is a cross-sectional view showing another example of the shape of a dike according to another exemplary embodiment of the present disclosure;

[0035] Figure 15 It is a cross-sectional view showing another example of the shape of a dike according to another exemplary embodiment of the present disclosure;

[0036] Figure 16 It is a cross-sectional view showing another example of the shape of a dike according to another exemplary embodiment of the present disclosure; and

[0037] Figure 17 It is a cross-sectional view showing another example of the shape of a dike according to another exemplary embodiment of the present disclosure. Detailed Description

[0038] Advantages and features of the present disclosure and methods for achieving these advantages and features will be clear by referring to the exemplary embodiments described in detail below in conjunction with the accompanying drawings. However, the present disclosure is not limited to the exemplary embodiments disclosed herein, but will be implemented in various forms. The exemplary embodiments are provided only as examples so that those skilled in the art can fully understand the disclosure content of the present disclosure and the scope of the present disclosure.

[0039] The shapes, sizes, ratios, angles, numbers, etc. shown in the drawings for describing the exemplary embodiments of the present disclosure are only examples, and the present disclosure is not limited thereto. Throughout the specification, the same reference numerals generally denote the same elements. In addition, in the following description of the present disclosure, detailed descriptions of known related technologies may be omitted to avoid unnecessarily obscuring the subject matter of the present disclosure. Terms such as "comprising", "having", and "consisting of" used herein generally intend to allow the addition of other components, unless these terms are used together with the term "only". Any reference to the singular may include the plural unless otherwise clearly stated.

[0040] Even if not explicitly stated, components are understood to include a normal error range.

[0041] When terms such as "above", "upper", "lower", and "next to" are used to describe the positional relationship between two parts, one or more parts may be located between the two parts unless these terms are used together with the terms "immediately" or "directly".

[0042] When an element or layer is referred to as being "on" another element or layer, it may be directly on the other element or layer, or there may be intervening elements or layers therebetween.

[0043] Although terms such as "first", "second", etc. are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from other components. Thus, in the technical concept of the present disclosure, the first component to be mentioned below may be the second component. Throughout the specification, like reference numerals generally denote like elements.

[0044] Throughout the specification, like reference numerals generally denote like elements.

[0045] The size and thickness of each component shown in the drawings are shown for convenience of illustration and are not limited to the size and thickness of the components shown in the embodiments of the present disclosure.

[0046] The features of the various embodiments of the present disclosure may be partially or wholly coupled or combined with each other, and may be interlocked and operated in various ways technically, and the various embodiments may be performed independently of each other or in association with each other.

[0047] Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the drawings.

[0048] Figure 1 is a block diagram of a display device according to an exemplary embodiment of the present disclosure.

[0049] Referring to Figure 1 , a display device 100 according to an exemplary embodiment of the present disclosure may include an image processor 151, a timing controller 152, a data driver 153, a gate driver 154, and a display panel DP.

[0050] The image processor 151 outputs a data signal DATA and a data enable signal DE supplied from the outside. In addition to the data enable signal DE, the image processor 151 may also output a driving signal including one or more of a vertical synchronization signal, a horizontal synchronization signal, and a clock signal.

[0051] The timing controller 152 receives a driving signal including a data enable signal DE and a data signal DATA from the image processor 151. The timing controller 152 outputs a gate timing control signal GDC for controlling the operation timing of the gate driver 154 and a data timing control signal DDC for controlling the operation timing of the data driver 153 based on the driving signal.

[0052] In response to the data timing control signal DDC supplied from the timing controller 152, the data driver 153 samples and latches the data signal DATA supplied from the timing controller 152. Then, the data driver 153 converts the sampled and latched data signal into a gamma reference voltage and outputs the gamma reference voltage. In addition, the data driver 153 outputs the data signal through data lines DL1 to DLn.

[0053] The gate driver 154 outputs a gate signal while shifting the level of the gate voltage in response to the gate timing control signal GDC supplied from the timing controller 152. In addition, the gate driver 154 outputs the gate signal through gate lines GL1 to GLm.

[0054] The display panel DP includes a plurality of pixels PX. Each of the plurality of pixels PX emits light and displays an image in response to the data signal and the gate signal supplied from the data driver 153 and the gate driver 154, respectively. The detailed structure of the pixel PX will be described in detail in Figure 2 and Figure 3 The detailed structure of the pixel PX will be described in detail in

[0055] Figure 2 is a plan view of a display device according to an exemplary embodiment of the present disclosure.

[0056] As Figure 2 shown, the display device 100 according to an exemplary embodiment of the present disclosure includes a substrate 110 provided with a plurality of pixels PX. Here, each pixel PX may be composed of a plurality of sub-pixels SP. Figure 2 An example of a pixel PX including three sub-pixels SP that emit light of different colors from each other is shown. For example, in the display device 100 according to an exemplary embodiment of the present disclosure, each pixel PX may include sub-pixels SP that emit red light (R), green light (G), and blue light (B), respectively. However, the number of sub-pixels SP included in the pixel PX is not limited thereto. For example, in addition to the sub-pixels SP that emit red light (R), green light (G), and blue light (B), respectively, each pixel PX may further include a sub-pixel SP that emits white light.

[0057] The substrate 110 is configured to support various components included in the display device 100. The substrate 110 may be made of an insulating material. In addition, the substrate 110 may be made of a flexible material to be bendable. In addition, the substrate 110 may be made of a transparent material. For example, the substrate 110 may be made of a plastic material such as polyimide (PI).

[0058] On the substrate 110, a plurality of gate lines GL extending in a first direction may cross a plurality of data lines DL extending in a second direction different from the first direction. Here, pixels PX are defined at respective intersections of the plurality of gate lines GL and the plurality of data lines DL on the substrate 110.

[0059] A region where a plurality of pixels PX for implementing an image on the substrate 110 are provided may be referred to as a display region AA. A region provided outside the display region AA and where no plurality of pixels PX are provided may be referred to as a non-display region NA.

[0060] A display unit for displaying an image and a circuit unit for driving the display unit may be provided in the display region AA. For example, if the display device 100 is an organic light-emitting display device, the display unit may include an organic light-emitting element. That is, the display unit may include an anode, an emission layer on the anode, and a cathode on the emission layer. Here, the emission layer may be an organic emission layer and may be composed of, for example, a hole transport layer, a hole injection layer, an organic emission layer, an electron injection layer, and an electron transport layer. However, if the display device 100 is a liquid crystal display device, the display unit may be configured to include a liquid crystal layer. Hereinafter, for ease of description, a description will be made under the assumption that the display device 100 is an organic light-emitting display device. However, the present disclosure is not limited thereto.

[0061] The circuit unit may include various transistors, capacitors, and lines for driving the light-emitting element. Specifically, the circuit unit may be composed of various components such as a driving transistor, a switching transistor, a storage capacitor, a gate line, and a data line, but is not limited thereto.

[0062] For example, each sub-pixel SP of the display device 100 according to an exemplary embodiment of the present disclosure may include a switching transistor, a driving transistor, a capacitor, and a light-emitting element.

[0063] The light-emitting element may operate to emit light in response to a driving current generated by the driving transistor.

[0064] The switching transistor may be turned on / off such that a data signal supplied through the data line DL in response to a gate signal supplied through the gate line GL is stored in the capacitor as a data voltage.

[0065] The driving transistor can operate in response to the data voltage stored in the capacitor, such that a constant driving current flows between the high-potential power line and the low-potential power line.

[0066] An example has been described in which each sub-pixel SP of the display device 100 according to an exemplary embodiment of the present disclosure has a 2T (transistor) 1C (capacitor) structure including a switching transistor, a driving transistor, and a capacitor. However, when a compensation circuit is added, the sub-pixel SP can have various structures, such as 3T1C, 4T2C, 5T2C, 6T1C, 6T2C, 7T1C, 7T2C, etc.

[0067] The compensation circuit is configured to compensate for the threshold voltage of the driving transistor. The compensation circuit can include at least one compensation thin-film transistor and at least one compensation capacitor. The configuration and structure of the compensation thin-film transistor and the compensation capacitor can vary according to the compensation method.

[0068] The non-display area NA is an area where an image is not displayed and various lines, circuits, etc. for driving the display units provided in the display area AA are provided.

[0069] The non-display area NA can be defined as Figure 2 the area surrounding the display area AA as shown, but is not limited thereto. The non-display area NA can be defined as an area extending from the display area AA. In addition, the non-display area NA can be defined as an area extending from multiple sides of the display area AA.

[0070] In addition, the non-display area NA can include a pad area provided for receiving external power, data driving signals, etc. or transmitting and receiving touch signals. In the pad area, external modules, such as driver ICs such as a data driver integrated circuit (IC) or a gate driver IC, can be provided.

[0071] The driver IC provided in the pad area can be connected to a plurality of lines and can be connected to a plurality of data lines DL or a plurality of gate lines GL provided in the display area AA through the plurality of lines. That is, the driver IC provided in the pad area can be electrically connected to each of the plurality of pixels PX.

[0072] In the non-display region NA, a bent region, which is a bendable part of the non-display region NA in one direction, may be located between the display region AA and the pad region. Since the non-display region NA is a region where an image is not displayed, there is no need to see this region on the upper surface of the substrate 110. Therefore, a part of the non-display region NA of the substrate 110 may be bent. For example, an edge on one side of the substrate 110 may be bent in the back surface direction to have a predetermined curvature. Here, the pad region may be positioned to overlap the display region AA in the back surface direction of the display region AA. Therefore, the non-display region NA may be reduced while ensuring a region for lines and drive circuits.

[0073] Figure 3 is a cross-sectional view taken along line I-I’ of Figure 2 and shows a sub-pixel provided in the display region of a display device according to an exemplary embodiment of the present disclosure.

[0074] Referring to Figure 3 FIG. 1, a display device 100 according to an exemplary embodiment of the present disclosure may include a substrate 110, a buffer layer 111, thin film transistors 200, and a gate insulating layer 112. In addition, the display device 100 may include a first interlayer insulating layer 113, a second interlayer insulating layer 114, connection electrodes 250, a planarization layer 115, light emitting elements 300, dams 400, and a packaging layer 120. In addition, the display device 100 may include a touch buffer layer 131, a touch insulating layer 132, an organic protection layer 133, touch sensors 500, a touch electrode protection layer 134, a light shielding layer 610, color filters 620, and a coating layer 135. Here, the packaging layer 120 is composed of multiple layers and includes a first inorganic packaging layer 121, an organic packaging layer 122, and a second inorganic packaging layer 123. In addition, the thin film transistors 200 include a semiconductor layer 210, gate electrodes 220, source electrodes 230, and drain electrodes 240. In addition, the light emitting elements 300 include a first electrode 310 serving as an anode, an emission layer 320, and a second electrode 330 serving as a cathode. In addition, the dams 400 are composed of multiple layers and include a first dam layer 410, a second dam layer 420, and a third dam layer 430.

[0075] The substrate 110 is for supporting and protecting components provided thereon. The substrate 110 may be a rigid substrate or a flexible substrate capable of being bent, folded, and curled.

[0076] When the substrate 110 is made of a flexible plastic material, it may be made of, for example, polyimide (PI). When the substrate 110 is made of polyimide (PI), the manufacturing process of the display device 100 is performed in a state where a support substrate made of glass is disposed below the substrate 110. After the manufacturing process of the display device 100 is completed, the support substrate may be released.

[0077] In addition, after releasing the support substrate, a backplane for supporting the substrate 110 may be disposed under the substrate 110. For example, when the backplane is further disposed under the substrate 110, the backplane may not be disposed in a portion overlapping with the bending region of the substrate 110, but is not limited thereto.

[0078] When the substrate 110 is made of polyimide (PI), moisture may penetrate through the substrate 110 made of polyimide (PI) to the thin film transistor 200 or the light emitting element 300. Therefore, the performance of the display device 100 may deteriorate. Accordingly, the substrate 110 of the display device 100 according to an exemplary embodiment of the present disclosure may be made of double polyimide (PI) to inhibit the deterioration of the performance of the display device 100 caused by moisture penetration.

[0079] In addition, the display device 100 according to an exemplary embodiment of the present disclosure may further include an inorganic film disposed between the double polyimides (PI) of the substrate 110. Accordingly, product reliability may be improved by blocking charges implanted in the lower polyimide (PI). In addition, a process of forming a metal layer to block charges implanted in the polyimide (PI) may be omitted. Accordingly, the entire process may be simplified and production costs may be reduced. For example, the inorganic film between the double polyimides (PI) may be an inorganic insulating film formed of a single layer of silicon nitride (SiNx) or silicon oxide (SiOx) or a multi-layer configuration thereof.

[0080] The buffer layer 111 may be disposed on the substrate 110. Here, the buffer layer 111 may be a multi-buffer layer including a plurality of inorganic films.

[0081] The semiconductor layer 210 of the thin film transistor 200 is disposed on the buffer layer 111. The buffer layer 111 may be configured to protect the semiconductor layer 210 and enhance the interfacial adhesion of the semiconductor layer 210.

[0082] The display device 100 according to an exemplary embodiment of the present disclosure may further include a metal layer disposed under one of the plurality of films of the buffer layer 111. The metal layer may be used as a light-shielding portion.

[0083] The thin film transistor 200 may be disposed on the buffer layer 111. The thin film transistor 200 includes a semiconductor layer 210, a gate electrode 220, a source electrode 230, and a drain electrode 240. According to the design of the pixel circuit, the source electrode 230 may be used as the drain electrode, and the drain electrode 240 may be used as the source electrode.

[0084] The semiconductor layer 210 may include a channel region overlapping with the gate electrode 220, and a first region and a second region respectively located on both sides of the channel region and connected to the source electrode 230 and the drain electrode 240.

[0085] The gate insulating layer 112 is disposed on the semiconductor layer 210 and is used to insulate the semiconductor layer 210 from the gate electrode 220. The gate insulating layer 112 may cover the semiconductor layer 210 and may be disposed on the front surface of the display area AA. The gate insulating layer 112 may be made of an inorganic insulating material, such as silicon oxide (SiO2), silicon nitride (SiNx), or silicon oxynitride (SiON), or a multi-layer thereof, but is not limited thereto.

[0086] The gate electrode 220 is disposed on the gate insulating layer 112 and overlaps the semiconductor layer 210, wherein the gate insulating layer 112 is disposed between the gate electrode 220 and the semiconductor layer 210. The gate electrode 220 may be configured by a single layer or a multi-layer of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof, but is not limited thereto.

[0087] The first interlayer insulating layer 113 is disposed on the gate electrode 220. The first interlayer insulating layer 113 may cover the gate electrode 220 and may be formed on the front surface of the display area AA. The first interlayer insulating layer 113 may be made of the same inorganic insulating material as the gate insulating layer 112, such as silicon oxide (SiO2), silicon nitride (SiNx), or silicon oxynitride (SiON), or a multi-layer thereof, but is not limited thereto.

[0088] The source electrode 230 and the drain electrode 240 are disposed to be spaced apart from each other on the first interlayer insulating layer 113. The source electrode 230 and the drain electrode 240 are electrically connected to the semiconductor layer 210 through contact holes penetrating the first interlayer insulating layer 113 and the gate insulating layer 112.

[0089] Figure 3 It is shown that the thin film transistor 200 is a top-gate type in which the gate electrode 220 is located on the semiconductor layer 210, but the present disclosure is not limited thereto. That is, the thin film transistor 200 may be a bottom-gate type in which the gate electrode 220 is located below the semiconductor layer 210, or a double-gate type in which the gate electrode 220 is located above and below the semiconductor layer 210.

[0090] In addition, Figure 3 It is shown that one thin film transistor 200 corresponds to one sub-pixel SP. However, the number and type of thin film transistors 200 corresponding to one sub-pixel SP are not limited thereto. For example, Figure 3 Only the driving transistor for driving the light-emitting element 300 is shown as the thin film transistor 200. However, each sub-pixel SP may further include a switching transistor corresponding to the light-emitting element.

[0091] The connection electrode 250 may be disposed on the thin film transistor 200. The second interlayer insulating layer 114 may be disposed on the front surface of the display area AA and between the thin film transistor 200 and the connection electrode 250.

[0092] The connection electrode 250 is connected to the drain electrode 240 of the thin film transistor 200 through a contact hole penetrating the second interlayer insulating layer 114.

[0093] The planarization layer 115 is disposed on the front surface of the display area AA and on the connection electrode 250. The planarization layer 115 is configured to planarize the first electrode 310 of the light emitting element 300 divided by the bank 400. For example, the planarization layer 115 may be made of a resin such as acrylate and polyimide (PI).

[0094] The light emitting element 300 is disposed on the planarization layer 115. The light emitting element 300 may include a first electrode 310, an emission layer 320, and a second electrode 330 stacked in sequence. The first electrode 310 disposed on the planarization layer 115 is connected to the connection electrode 250 through a contact hole penetrating the planarization layer 115. Accordingly, the first electrode 310 is electrically connected to the thin film transistor 200.

[0095] Hereinafter, an example of a top emission type in which light is emitted above the substrate 110 on which the light emitting element 300 is disposed in the display device 100 according to an exemplary embodiment of the present disclosure will be described. Here, the first electrode (i.e., anode) 310 of the light emitting element 300 may further include a transparent conductive layer and a reflective layer on the transparent conductive layer. The transparent conductive layer may be made of a transparent conductive material such as ITO or IZO. The reflective layer may be made of, for example, silver (Ag), aluminum (Al), gold (Au), molybdenum (Mo), tungsten (W), chromium (Cr), or an alloy thereof.

[0096] In addition, the bank 400 that divides the plurality of sub-pixels SP is disposed on the planarization layer 115. That is, the bank 400 is disposed on the planarization layer 115 and includes an opening in a portion overlapping with the light emitting element 300 of each sub-pixel SP to expose a part of the first electrode 310 of the light emitting element 300.

[0097] The bank 400 of the display device 100 according to an exemplary embodiment of the present disclosure is composed of a plurality of layers. The bank 400 includes a first bank layer 410 that is in direct contact with the first electrode 310 of the light emitting element 300 and a second bank layer 420 that is in contact with a part of the first bank layer 410. In addition, the bank 400 includes a third bank layer 430 that covers all of the second bank layer 420 and at least a part of the first bank layer 410.

[0098] For example, each of the first bank layer 410, the second bank layer 420, and the third bank layer 430 may be made of an organic material. According to an exemplary embodiment of the present disclosure, each of the first bank layer 410, the second bank layer 420, and the third bank layer 430 is made of an organic material. Therefore, these bank layers have a higher degree of freedom in shape than banks made of inorganic materials. In addition, it is easy to adjust the height, width, and slope of each bank layer. For example, damage to the first electrode 310 during the manufacturing process can be minimized. However, the present disclosure is not limited thereto.

[0099] For example, the first bank layer 410 may be made of an organic insulating material and may be made of a transparent material. During the process of preparing the bank 400, when a part of the photoresist PR coated on the metal pattern of the first electrode 310 for forming the light-emitting element 300 remains, the first bank layer 410 may be formed.

[0100] The first bank layer 410 may be made of a positive photosensitive material, such as a polyimide-based polymer.

[0101] The first bank layer 410 may be in contact with the end point of the first electrode 310 of the light-emitting element 300. Here, the first bank layer 410 includes an inner portion in the direction toward the first electrode 310 based on a vertical line passing through the maximum height portion and an outer portion opposite to the inner portion.

[0102] The second bank layer 420 may be a black bank containing a light-shielding black material such as a black pigment. The second bank layer 420 may cover all regions (i.e., non-emitting regions) that do not overlap with the first electrode 310 of the light-emitting element 300. In addition, the second bank layer 420 may suppress optical interference between adjacent sub-pixels SP.

[0103] The second bank layer 420 may be made of a material having different optical properties from the first bank layer 410 (i.e., a negative photosensitive material, such as an epoxy-based polymer).

[0104] The second bank layer 420 is disposed on the planarization layer 115 to be in contact with the outer portion of the first bank layer 410.

[0105] The third bank layer 430 is disposed on the second bank layer 420 to cover the second bank layer 420. In addition, the third bank layer 430 is disposed to be in contact with the outer portion of the first bank layer 410.

[0106] The third bank layer 430 may be made of the same material as the first bank layer 410, but is not limited thereto. The third bank layer 430 and the first bank layer 410 may be made of a material suitable for patterning the electrode (i.e., metal) of the light-emitting element, selected from materials that release a small amount of exhaust gas and have high reliability.

[0107] That is, as Figure 3 shown, the second bank layer 420 can be surrounded by at least one of the first bank layer 410 and the third bank layer 430. Thus, during the process of preparing the second bank layer 420, the first electrode 310 of the light-emitting element 300 is not exposed at all. Therefore, processes and materials that may cause oxidation or contamination of the first electrode 310 do not affect the first electrode 310.

[0108] Reference will be made to Figures 4A to 6B describe in detail the process of preparing the bank 400 including multiple layers according to an exemplary embodiment of the present disclosure. In addition, reference will be made to Figures 7 to 17 describe in detail the structure of the bank 400 including multiple layers.

[0109] The encapsulation layer 120 is disposed on the light-emitting element 300 and the bank 400.

[0110] Figure 3 An example is shown in which the emission layer 320 and the second electrode 330 of the light-emitting element 300 are sequentially stacked on the first electrode 310 and are provided to cover the upper portion of the bank 400. Here, the encapsulation layer 120 covers the light-emitting element 300 and is disposed on the front surface of the display area AA. However, the emission layer 320 and the second electrode 330 of the light-emitting element 300 may be located inside the opening of the bank 400 and may be disposed outside the opening of the bank 400 so as to overlap a part of the bank 400. In this case, the encapsulation layer 120 may be provided to be in direct contact with the bank 400 and the light-emitting element 300.

[0111] The encapsulation layer 120 may have a single-layer structure or a multi-layer structure. For example, as Figure 3 shown, the encapsulation layer 120 may have a structure in which a first inorganic encapsulation layer 121, an organic encapsulation layer 122, and a second inorganic encapsulation layer 123 are sequentially stacked. In this case, the organic encapsulation layer 122 may have the largest thickness and serve as a planarization layer.

[0112] The first inorganic encapsulation layer 121 may be disposed on the second electrode 330 to be closest to the light-emitting element 300. The first inorganic encapsulation layer 121 may be made of an inorganic insulating material suitable for low-temperature deposition. For example, the first inorganic encapsulation layer 121 may be made of silicon nitride (SiNx), silicon oxide (SiOx), silicon oxynitride (SiON), or aluminum oxide (Al2O3). Since the first inorganic encapsulation layer 121 is deposited in a low-temperature atmosphere, damage to the emission layer 320 including organic materials susceptible to high temperatures during the deposition process can be suppressed.

[0113] The organic encapsulation layer 122 may be disposed on the first inorganic encapsulation layer 121 to cover the front surface of the display area AA. In addition, the organic encapsulation layer 122 may be used to buffer the stress generated between the layers during the bending of the display device (such as a flexible display device) 100 and enhance the planarization performance. The organic encapsulation layer 122 has a smaller area than the first inorganic encapsulation layer 121. In this case, the organic encapsulation layer 122 may be disposed to expose both end points of the first inorganic encapsulation layer 121. For example, the organic encapsulation layer 122 may be made of an organic insulating material, such as acrylic resin, epoxy resin, polyimide, polyethylene, or silicon oxycarbide (SiOC). In addition, the organic encapsulation layer 122 may be prepared by an inkjet method, but is not limited thereto.

[0114] The second inorganic encapsulation layer 123 is disposed on the organic encapsulation layer 122. Here, the second inorganic encapsulation layer 123 may minimize or prevent the penetration of external moisture or oxygen into the first inorganic encapsulation layer 121 and the organic encapsulation layer 122. To this end, the second inorganic encapsulation layer 123 may be disposed to cover the upper surface and the side surfaces of the organic encapsulation layer 122 and the first inorganic encapsulation layer 121. For example, the second inorganic encapsulation layer 123 may be made of an inorganic insulating material, such as silicon nitride (SiNx), silicon oxide (SiOx), silicon oxynitride (SiON), or aluminum oxide (Al2O3).

[0115] Among them, in the non-display area NA of the display device 100 according to an exemplary embodiment of the present disclosure, one or more shielding structures may be provided to block the flow of the organic encapsulation layer 122 constituting the encapsulation layer 120. For example, each of the shielding structures may be formed as a dam having a predetermined height capable of blocking the flow of the organic encapsulation layer 122. In addition, each of the shielding structures is disposed in the non-display area NA to have a closed curved shape surrounding the display area AA. Here, the first inorganic encapsulation layer 121 and the second inorganic encapsulation layer 123 are disposed on the shielding structure, and the flow of the organic encapsulation layer 122 may be blocked by the shielding structure. The shielding structure needs to have a predetermined height or a higher height to block the flow of the organic encapsulation layer 122. Each of the shielding structures may be composed of at least one layer made of an organic material. For example, each of the shielding structures may include a lower layer made of the same material as the planarization layer 115 and an upper layer made of the same material as at least one of the first to third dam layers 410, 420, and 430 of the dam 400, but is not limited thereto.

[0116] In the display device 100 according to an exemplary embodiment of the present disclosure, at least one of the touch sensor layer and the color filter layer may be disposed on the encapsulation layer 120.

[0117] The touch sensor layer may include a touch buffer layer 131, a touch insulating layer 132, an organic protective layer 133, a touch sensor 500, and a touch electrode protective layer 134. The touch sensor 500 may include a plurality of touch electrodes 510 and a plurality of bridging electrodes 520.

[0118] Specifically, the touch buffer layer 131 may be disposed on the second inorganic encapsulation layer 123 of the encapsulation layer 120, and the touch sensor 500 may be disposed on the touch buffer layer 131.

[0119] The touch buffer layer 131 covers the encapsulation layer 120, so it can protect the encapsulation layer 120 and inhibit moisture penetration. In addition, the touch buffer layer 131 can be used to reduce the parasitic capacitance between the second electrode 330 of the light-emitting element 300 and the touch electrodes included in the touch sensor 500.

[0120] The touch buffer layer 131 may be made of an organic insulating material, which can be formed at a low temperature of, for example, 100 °C or lower and has a low dielectric constant of 1 to 3 to inhibit damage to the emission layer 320 containing organic materials vulnerable to high temperatures. For example, the touch buffer layer 131 may be made of an acrylic-based material, an epoxy-based material, or a siloxane-based material. In addition, when the flexible display device 100 is bent, the electrodes (i.e., metals) of the touch sensor 500 located on the touch buffer layer 131 have a risk of being damaged. However, the touch buffer layer 131 made of an organic material can inhibit damage to the encapsulation layer 120 and the metals constituting the touch sensor 500.

[0121] The touch sensor 500 may include touch electrodes 510 and bridging electrodes 520 disposed on different layers from each other. The touch insulating layer 132 may be disposed between the touch electrodes 510 and the bridging electrodes 520. That is, the bridging electrodes 520 may be disposed on the touch buffer layer 131, the touch insulating layer 132 may be disposed on the bridging electrodes 520, and the touch electrodes 510 may be disposed on the touch insulating layer 132. The touch insulating layer 132 may be configured by an organic layer or an inorganic layer made of, for example, metal oxides, metal nitrides, silicon oxides, silicon nitrides, and silicon oxynitrides, but is not limited thereto.

[0122] The organic protective layer 133 may be further disposed on the touch insulating layer 132 between the touch electrodes 510 and the bridging electrodes 520.

[0123] Figure 3 A plurality of first touch electrodes 510 disposed adjacent to each other in the first direction and first bridging electrodes 520 electrically connecting the adjacent first touch electrodes 510 among the plurality of first touch electrodes 510 are shown. Figure 3The portion where the touch electrode 510 and the bridging electrode 520 are electrically connected to each other is not shown. However, Figure 3 It is a cross-sectional view of only the portion on the plane of the substrate 110. For example, two adjacent touch electrodes 510 can be connected to one bridging electrode 520 through contact holes penetrating the touch insulating layer 132.

[0124] The display device 100 according to an exemplary embodiment of the present disclosure may further include: a plurality of second touch electrodes disposed adjacent to each other in a second direction different from the first direction, and a second bridging electrode that electrically connects the adjacent second touch electrodes among the plurality of second touch electrodes. For example, one of the first touch electrode and the second touch electrode may be used as a sensing input electrode, and the other touch electrode may be used as a sensing output electrode. In addition, the first touch electrode and the second touch electrode may be electrically insulated from each other and may be dispersed in a mesh form so as not to overlap each other.

[0125] Each of the touch electrodes 510 of the touch sensor 500 may be arranged to overlap with the bank 400.

[0126] A touch electrode protection layer 134 may be provided on the touch sensor 500, and the touch electrode protection layer 134 covers the plurality of touch electrodes 510 such that the plurality of touch electrodes 510 are not exposed to the outside. For example, the touch electrode protection layer 134 may include an inorganic material such as silicon nitride (SiNx) or silicon oxide (SiO2), or an organic material such as polyacrylate resin, polyimide resin, and acrylic-based materials, but is not limited thereto.

[0127] The color filter layer may include a light-shielding layer 610 and a color filter 620.

[0128] The light-shielding layer 610 overlaps with the bank 400 and includes a plurality of openings, and each of the plurality of openings overlaps with the opening of the bank 400. For example, the light-shielding layer 610 may have a width smaller than that of the bank 400, and each opening of the light-shielding layer 610 may have a width larger than the corresponding opening of the bank 400.

[0129] The light-shielding layer 610 suppresses the recognition of external light incident from the outside and reflected by the lines of the display device 100. The light-shielding layer 610 may be positioned to overlap with the edge of the region where the light-emitting elements are provided (i.e., the emission region). Therefore, the light-shielding layer 610 can reduce the amount of external light incident on the emission region by absorbing the external light. For example, the light-shielding layer 610 may be a black matrix containing a black material.

[0130] The color filter 620 is located on the light-shielding layer 610. Most of the color filter 620 may overlap with the openings of the light-shielding layer 610, and a part of the color filter 620 may overlap with the light-shielding layer 610. For example, as Figure 3As shown, the color filter 620 may be formed to fill the openings in the light-shielding layer 610.

[0131] The color filter 620 suppresses the reflection and recognition of external light incident from the outside into the bank 400. Since the color filter 620 cannot completely block light, it can suppress the recognition of reflected light of external light while not reducing the efficiency of the light emitted from the emission layer 320 of the light-emitting element 300.

[0132] In addition, the emission layer 320 of the light-emitting element 300 included in the plurality of sub-pixels SP in the display device 100 according to an exemplary embodiment of the present disclosure may output white light. In this case, the color filters 620 corresponding to the plurality of sub-pixels SP included in one pixel PX as shown in Figure 3 may include: a red color filter that converts white light into red light, a blue color filter that converts white light into blue light, and a green color filter that converts white light into green light.

[0133] A coating layer 135 may be provided on the color filter layer.

[0134] The coating layer 135 may cover the light-shielding layer 610 and the color filter 620, thereby providing a flat surface for the upper portion. In addition, the coating layer 135 may prevent the upper portion from being contaminated by various pigments that may be contained in the color filter 620. For example, the coating layer 135 may be made of an acrylic-based resin or an epoxy-based resin. Alternatively, the coating layer 135 may be made of the same material as the planarization layer 115.

[0135] Furthermore, the display device 100 according to an exemplary embodiment of the present disclosure may further include a cover glass provided on the coating layer 135. The cover glass may be bonded to the coating layer 135 through an adhesive layer. The adhesive layer for bonding various components of the display device 100 to each other and the adhesive layer for bonding the cover glass to the coating layer 135 may be made of an optically transparent display adhesive. The optically transparent display adhesive may include, for example, a pressure-sensitive adhesive, an optically clear adhesive (OCR), or an optically transparent resin, but is not limited thereto.

[0136] The cover glass may protect the components of the display device 100 from external impacts and suppress damage such as scratches.

[0137] Hereinafter, a process of preparing the bank 400 of the display device 100 according to an exemplary embodiment of the present disclosure will be described in more detail with reference to Figures 4A to 6B is a cross-sectional view for explaining a process of forming a bank according to an exemplary embodiment of the present disclosure.

[0138] Figures 4A to 4G First, with reference to

[0139] First, refer toFigure 4A , a metal layer is provided on the planarization layer 115 to form the first electrode 310 (i.e., the anode) of the light-emitting element 300.

[0140] Figures 4B to 6B And Figure 4A shows Figure 3 the structure in which a buffer layer 111, a gate insulating layer 112, a first interlayer insulating layer 113, a second interlayer insulating layer 114, and a planarization layer 115 are sequentially stacked on the substrate 110 of the display device 100. In a state where the planarization layer 115 is stacked on the substrate 110, the first electrode 310 and the bank 400 are provided on the planarization layer 115.

[0141] For ease of explanation, Figures 4A to 6B other components except for the plurality of layers stacked on the substrate 110 are not shown. However, components substantially the same as the thin-film transistor 200 and the connection electrode 250 shown may also be provided between the substrate 110 and the planarization layer 115. In this case, as Figure 3 shown, the first electrode 310 is connected to the connection electrode 250 through a contact hole penetrating the planarization layer 115. Figure 3 shown, the first electrode 310 is connected to the connection electrode 250 through a contact hole penetrating the planarization layer 115.

[0142] Then, referring to Figure 4B , a photoresist PR is coated on the upper surface of the metal layer for forming the first electrode 310 of the light-emitting element 300. Then, the photoresist PR is exposed and developed by using a mask having a shape corresponding to the electrode pattern to be formed.

[0143] A part of the photoresist PR coated on the upper surface of the metal layer for forming the first electrode 310 remains in contact with the first electrode 310 even after the process of preparing the bank described later is completed. The remaining part of the photoresist PR is the first bank layer 410.

[0144] The photoresist PR coated on the upper surface of the metal layer for forming the first electrode 310 may be made of a positive photosensitive material that remains where it is not exposed to light.

[0145] Then, referring to Figure 4C , the metal layer outside the photoresist PR remaining after development is etched to pattern the first electrode 310 of the light-emitting element 300. For example, the metal layer can be etched by wet etching.

[0146] After that, referring to Figure 4D , the photoresist PR coated on the pattern of the first electrode 310 is cured. The curing process is performed at a predetermined temperature. Thus, as Figure 4DAs shown, a reflow process is performed on the photoresist PR coated on the pattern of the first electrode 310. Accordingly, the photoresist PR is stably bonded and covers not only the upper surface but also the side surface of the pattern of the first electrode 310.

[0147] Then, with reference to Figure 4E , in a state where the photoresist PR covering the pattern of the first electrode 310 is not peeled off but maintained, a material layer for forming the second bank layer 420 (e.g., a black bank) is coated on the planarization layer 115 and the first electrode 310. Then, the material layer is etched such that the second bank layer 420 contacts a part of the photoresist PR, and most of the upper surface of the photoresist PR (i.e., the upper surface of the first electrode 310) is exposed. For example, the material layer for forming the second bank layer 420 can be etched by plasma ashing.

[0148] Accordingly, the photoresist PR on the pattern of the first electrode 310 serves as a shielding layer. Accordingly, direct contamination of the surface of the first electrode 310 caused by the material layer for forming the second bank layer 420 can be suppressed. In addition, damage to the first electrode 310 that may occur during the process of etching the material layer for forming the second bank layer 420 can be suppressed. Accordingly, the reliability of the device can be improved.

[0149] The material layer for forming the second bank layer 420 can be made of a material that has different optical characteristics from the photoresist PR coated on the upper surface of the metal layer for forming the first electrode 310. The material layer can be made of, for example, a negative photosensitive material that remains where exposed to light. In addition, the material layer for forming the second bank layer 420 can include a black material.

[0150] After that, with reference to Figure 4F , a material layer for forming the third bank layer 430 is coated on the second bank layer 420 and the photoresist PR. Here, the material layer for forming the third bank layer 430 can be made of the same material as the photoresist PR, but is not limited thereto. For example, each of the first bank layer 410 and the third bank layer 430 can be made of a transparent material.

[0151] Then, with reference to Figure 4G , the photoresist PR on the pattern of the first electrode 310 and the material layer PR corresponding to the third bank layer 430 are removed. Accordingly, the bank 400 is formed. The bank 400 includes: the first bank layer 410 in contact with the end point of the first electrode 310, the second bank layer 420 in contact with the outer portion of the first bank layer 410, and the third bank layer 430 covering all of the second bank layer 420 and in contact with at least a part of the first bank layer 410.

[0152] By performing the processes of removing the photoresist PR on the pattern of the first electrode 310 and the material layer PR corresponding to the third bank layer 430 as shown in Figure 4F and Figure 4G All contaminants are removed together with the photoresist PR on the pattern of the first electrode 310. Therefore, the reliability of the device can be greatly improved.

[0153] For example, the processes of removing the photoresist PR on the pattern of the first electrode 310 and the material layer PR corresponding to the third bank layer 430 can be exposure and development processes using a halftone mask. Therefore, the slope of the portion adjacent to the first electrode 310 in the bank 400 can be selectively adjusted. Therefore, a low-reflection structure for the light-emitting element can be ensured, and the flow of excessive light leakage current between the light-emitting elements can also be suppressed.

[0154] Figure 5A and Figure 5B are cross-sectional views for illustrating an example of the process of removing some layers of the bank according to an exemplary embodiment of the present disclosure.

[0155] First, referring to Figure 5A , in a state where a material layer for forming the third bank layer 430 is coated on the second bank layer 420 and the photoresist PR as shown in Figure 4F , exposure is performed using a halftone mask M that exposes the pattern of the first electrode 310.

[0156] Then, referring to Figure 5B , development and ashing processes are performed on the photoresist PR on the exposed pattern of the first electrode 310 and the material layer PR corresponding to the third bank layer 430.

[0157] Each of the photoresist PR on the pattern of the first electrode 310 and the material layer PR corresponding to the third bank layer 430 can be made of a positive photosensitive material. Therefore, the portions corresponding to the non-transmissive region and the semi-transmissive region of the halftone mask M are retained, and the portions corresponding to the transmissive region of the halftone mask M and overlapping with the first electrode 310 are removed. Here, the photoresist PR and the material layer PR in the semi-transmissive region can be stacked to a smaller height compared to the photoresist PR and the material layer PR in the non-transmissive region of the halftone mask M. By the halftone mask process, the height and slope of the first bank layer 410 and the third bank layer 430 adjacent to the first electrode 310 can be adjusted. For example, the first bank layer 410 can be conical, and its slope can be selectively adjusted.

[0158] Among them, the second dam layer 420 can be made of a material having optical characteristics different from those of the photoresist PR on the pattern of the first electrode 310 and the material layer PR corresponding to the third dam layer 430, that is, a negative photosensitive material. However, as Figure 5A shown, the second dam layer 420 is completely covered by the material layer PR corresponding to the third dam layer 430 and is thus not affected by the exposure. In addition, the second dam layer 420 can be made of a material that is not damaged by a developer (e.g., an alkaline developer). The developer develops the photoresist PR on the pattern of the first electrode 310 and the material layer PR corresponding to the third dam layer 430.

[0159] Figure 6A and Figure 6B are cross-sectional views for explaining another example of a process of removing some layers of the dam according to an exemplary embodiment of the present disclosure.

[0160] First, referring to Figure 6A , in a state where a material layer PR for forming the third dam layer 430 is coated on the second dam layer 420 and the photoresist PR as shown in Figure 4F , a strip process is performed. Therefore, the photoresist PR and the material layer PR corresponding to the third dam layer 430 are stripped by a PR stripper, thereby exposing the pattern of the first electrode 310.

[0161] Then, referring to Figure 6B , a rinsing process is performed on the exposed photoresist PR and the material layer PR corresponding to the third dam layer 430 of the first electrode 310.

[0162] The photoresist PR on the pattern of the first electrode 310 and the material layer PR corresponding to the third dam layer 430 are made of the same type of photosensitive material. Therefore, the photoresist PR and the material layer PR can be removed together by a PR stripper. Among them, the second dam layer 420 can be made of a material having stronger chemical properties with respect to the PR stripper than the photoresist PR on the pattern of the first electrode 310 and the material layer PR corresponding to the third dam layer 430. Therefore, the second dam layer 420 is not affected by the stripping process.

[0163] Regarding the display device 100 according to an exemplary embodiment of the present disclosure, the following process can be applied as described above with reference to Figure 5A and Figure 5B : using a mask to remove the photoresist corresponding to the first dam layer 410 and the material layer corresponding to the third dam layer 430. Alternatively, it can be as described above with reference to Figure 6A and Figure 6BApply the process of chemically removing the photoresist and the material layer as described above. Additionally, a combination of two processes can be applied. In this document, the order of applying the two removal processes is not limited.

[0164] Hereinafter, with reference to Figures 7 to 12 Describe various examples of the shape of the bank according to exemplary embodiments of the present disclosure.

[0165] For ease of explanation, Figures 7 to 12 Configurations that are substantially the same as those of the display device 100 described above with reference to Figure 3 are not shown.

[0166] Figure 7 is a cross-sectional view showing an example of the shape of the bank according to an exemplary embodiment of the present disclosure.

[0167] As Figure 7 shown, the first bank layer 410 of the bank 400 contacts the end point of the first electrode 310 and also covers a part of the upper surface and the side surface of the first electrode 310.

[0168] Here, the second bank layer 420 contacts an outer portion of the first bank layer 410, and this outer portion is provided in a direction opposite to the direction toward the first electrode 310 based on a vertical line passing through the maximum height portion. Additionally, each of the end points of the second bank layer 420 and the third bank layer 430 can contact a part of the upper surface of the first bank layer 410. Accordingly, the second bank layer 420 can be surrounded by the first bank layer 410 and the third bank layer 430.

[0169] In addition, the heights of the second bank layer 420 and the third bank layer 430 can gradually decrease as they approach the first bank layer 410.

[0170] The shapes of the first bank layer 410 to the third bank layer 430 described above can be formed by the process of preparing the bank with reference to Figure 4A and Figure 6B described above.

[0171] Figure 8 is a cross-sectional view showing another example of the shape of the bank according to an exemplary embodiment of the present disclosure.

[0172] As Figure 8 shown, the first bank layer 410 of the bank 400 contacts the end point of the first electrode 310 and also covers a part of the upper surface and the side surface of the first electrode 310.

[0173] In this text, the endpoints of the second dam layer 420 can be in contact with the outer portion of the first dam layer 410, and the endpoints of the third dam layer 430 can be in contact with the outer portion of the first dam layer 410. Therefore, the second dam layer 420 can be surrounded by the first dam layer 410 and the third dam layer 430.

[0174] In addition, the first dam layer 410 has a shape that is asymmetric with respect to the center line in the vertical direction and has a shape in which the inner portion has a steeper slope than the outer portion.

[0175] Compared with Figure 7 the first dam layer 410 shown, Figure 8 the first dam layer 410 shown can have a similar height and a greater width. In this text, the height of each of the first dam layer 410, the second dam layer 420, and the third dam layer 430 refers to the distance in the vertical direction from the upper surface of the corresponding dam layer to the layer on which the first electrode 310 is provided (for example, the planarization layer 115).

[0176] The shapes of the first dam layer 410 to the third dam layer 430 described above can be achieved by applying different widths of the photoresist PR coated on the metal layer of the first electrode 310 and different shapes of the mask in the process of preparing the dam layer referred to above with reference to Figure 4A and Figure 6B description.

[0177] Figure 9 is a cross-sectional view showing another example of the shape of the dam layer according to an exemplary embodiment of the present disclosure.

[0178] As Figure 9 shown, the first dam layer 410 of the dam 400 is in contact with the endpoints of the first electrode 310 and also covers a part of the upper surface and the side surface of the first electrode 310.

[0179] Each of the endpoints of the second dam layer 420 and the third dam layer 430 can be in contact with the upper surface of the first dam layer 410.

[0180] In this text, the maximum height of the portion where the second dam layer 420 overlaps with the first dam layer 410 in the vertical direction can be set to be greater than the maximum height of the portion where the second dam layer 420 does not overlap with the first dam layer 410 in the vertical direction.

[0181] In addition, the third dam layer 430 completely covers the second dam layer 420. In addition, the maximum height of the portion where the third dam layer 430 overlaps with the first dam layer 410 in the vertical direction can be set to be greater than the maximum height of the portion where the third dam layer 430 does not overlap with the first dam layer 410 in the vertical direction. Therefore, the second dam layer 420 can be surrounded by the first dam layer 410 and the third dam layer 430.

[0182] Compared with Figure 7 the first dam layer 410 shown, Figure 9 the first dam layer 410 shown may have a similar width and a greater maximum height.

[0183] The shapes of the above-mentioned first dam layer 410 to third dam layer 430 can be achieved by: in the process of preparing the dam referred to above with reference to Figure 4A and Figure 6B described, applying different heights of the photoresist PR coated on the metal layer of the first electrode 310 and different shapes of the mask.

[0184] Figure 10 is a cross-sectional view showing another example of the shape of the dam according to an exemplary embodiment of the present disclosure.

[0185] As Figure 10 shown, the first dam layer 410 of the dam 400 contacts the end point of the first electrode 310, and also covers a part of the upper surface and the side surface of the first electrode 310.

[0186] Herein, the end point of the second dam layer 420 may contact the outer part of the first dam layer 410, and the end point of the third dam layer 430 may contact the outer part of the first dam layer 410. Therefore, the second dam layer 420 may be surrounded by the first dam layer 410 and the third dam layer 430.

[0187] In addition, the height of the second dam layer 420 in the contact part between the first dam layer 410 and the second dam layer 420 may be set to be less than the maximum height of the first dam layer 410. In addition, the height of the third dam layer 430 in the contact part between the first dam layer 410 and the third dam layer 430 may be set to be less than the maximum height of the first dam layer 410.

[0188] Compared with Figure 7 the first dam layer 410 shown, Figure 10 the first dam layer 410 shown may have a similar width and a greater maximum height.

[0189] The shapes of the above-mentioned first dam layer 410 to third dam layer 430 can be achieved by: in the process of preparing the dam referred to above with reference to Figure 4A and Figure 6B described, applying different heights of the photoresist PR coated on the metal layer of the first electrode 310 and different shapes of the mask.

[0190] Figure 11 is a cross-sectional view showing another example of the shape of the dam according to an exemplary embodiment of the present disclosure.

[0191] As Figure 11As shown, the first embankment layer 410 of the embankment 400 contacts the end point of the first electrode 310, and also covers a part of the upper surface and the side surface of the first electrode 310.

[0192] In this document, the end point of the second embankment layer 420 can contact an external part of the first embankment layer 410, and the third embankment layer 430 can cover at least a part of the upper surface of the first embankment layer 410. Therefore, the second embankment layer 420 can be surrounded by the first embankment layer 410 and the third embankment layer 430.

[0193] In addition, the height of the third embankment layer 430 in the part where the first embankment layer 410 and the third embankment layer 430 overlap in the vertical direction can be set to be greater than the height of the third embankment layer 430 in the part where the first embankment layer 410 does not overlap with the third embankment layer 430 in the vertical direction.

[0194] Compared with Figure 7 the first embankment layer 410 shown, Figure 11 the first embankment layer 410 shown can have a similar width and a greater maximum height.

[0195] The shapes of the above-mentioned first embankment layer 410 to third embankment layer 430 can be achieved by: in the process of preparing the embankment referred to above with reference to Figure 4A and Figure 6B described, applying different heights of the photoresist PR coated on the metal layer of the first electrode 310 and different shapes of the mask.

[0196] Figure 12 FIG. is a cross-sectional view showing another example of the shape of the embankment according to an exemplary embodiment of the present disclosure.

[0197] As Figure 12 shown, the first embankment layer 410 of the embankment 400 contacts the end point of the first electrode 310, and also covers a part of the upper surface and the side surface of the first electrode 310.

[0198] In this document, the first embankment layer 410 can have an asymmetric shape with respect to the center line in the vertical direction. In addition, the first embankment layer 410 can have the following shape: wherein the maximum height part is located in a region opposite to the region where the first electrode 310 is provided based on the center line of the first embankment layer 410.

[0199] Specifically, as Figure 12As shown, one of the vertical lines passing through the first bank layer 410 can be set as the center line m. In this document, the distance d1 from the center line m to the end point of the inner part of the first bank layer 410 is equal to the distance d2 from the center line m to the end point of the outer part of the first bank layer 410. In this document, the maximum height point hp of the first bank layer 410 can be located in a region opposite to the region where the first electrode 310 in contact with the first bank layer 410 is provided, based on the center line m.

[0200] In addition, each of the second bank layer 420 and the third bank layer 430 can cover the entire outer part and a part of the inner part of the first bank layer 410. In this document, the third bank layer 430 completely covers each of the second bank layer 420 and the first bank layer 410. In addition, the contact portion between the end point of the third bank layer 430 and the first bank layer 410 can be positioned closer to the region where the first electrode 310 is provided, compared with the contact portion between the end point of the second bank layer 420 and the first bank layer 410. Therefore, the second bank layer 420 can be surrounded by the first bank layer 410 and the third bank layer 430.

[0201] Compared with Figures 7 to 11 the first bank layer 410 shown in each of Figure 12 the first bank layer 410 shown can have a greater width and a greater maximum height.

[0202] The shapes of the above-mentioned first bank layer 410 to third bank layer 430 can be achieved by: in the process of preparing the bank referred to above with reference to Figure 4A and Figure 6B describing, applying different heights and widths of the photoresist PR coated on the metal layer of the first electrode 310 and different shapes of the mask.

[0203] The display device 100 according to another exemplary embodiment of the present disclosure may further include a spacer. The spacer is provided together with the first bank layer 410 described above with reference to Figures 7 to 11 and is configured to maintain a uniform gap with the stacked structure provided thereon.

[0204] The spacer according to another exemplary embodiment of the present disclosure may have the same shape as the Figure 12 first bank layer 410 shown and may be included as a part of the bank 400. Hereinafter, various examples of the shape of the bank according to another exemplary embodiment of the present disclosure will be described with reference to Figures 13 to 17 description.

[0205] Figures 13 to 17 The configuration of the display device 100 described above with reference to Figure 3 is not shown, and the above-mentioned reference to Figures 7 to 12Portions of the described dams that are substantially the same in shape.

[0206] Figure 13 It is a cross-sectional view showing an example of the shape of a dam according to another exemplary embodiment of the present disclosure.

[0207] A portion of the dam 400 disposed on the planarization layer 115 may have any one of the shapes of the first dam layer 410 described above with reference to Figures 7 to 11 In addition, another portion of the dam 400 may include: a first dam layer 410-1 having any one of the shapes of the first dam layer 410 described above with reference to Figures 7 to 11 In addition, a fourth dam layer 410-2 having the same shape as the first dam layer 410 described above with reference to Figure 12 described first dam layer 410.

[0208] As Figure 13 shown, the shape of the first dam layer 410-1 included in the dam 400 may be the same as or similar to the shape of the first dam layer 410 described above with reference to Figure 7 In addition, the shape of the fourth dam layer 410-2 included in the dam 400 may be the same as or similar to the shape of the first dam layer 410 described above with reference to Figure 12 described first dam layer 410.

[0209] In the dam 400, the second dam layer 420 covers an outer portion and a part of an inner portion of the fourth dam layer 410-2. The third dam layer 430 completely covers the second dam layer 420 and the fourth dam layer 410-2.

[0210] In addition, the fourth dam layer 410-2 may have an asymmetric shape. In addition, the maximum height portion of the fourth dam layer 410-2 may be located in a region opposite to the region where the first electrode 310 is provided based on the center line of the fourth dam layer 410-2 in the vertical direction.

[0211] The fourth dam layer 410-2 may be made of the same material as the first dam layer 410-1 and is provided on the same layer as the first dam layer 410-1.

[0212] Herein, the fourth dam layer 410-2 included in the dam 400 may be in contact with the end point of the first electrode 310 and may have a height greater than that of the first dam layer 410-1. In addition, the fourth dam layer 410-2 may have a width greater than that of the first dam layer 410-1.

[0213] As Figure 13 shown, the difference between the maximum height portion of the first dam layer 410-1 and the maximum height portion of the fourth dam layer 410-2 may be a first height hd1.

[0214] For example, the first height hd1 may be equal to or greater than that described above with reference toFigure 7 The height of the described first embankment layer 410. This can be achieved by: in the process of preparing the embankment referred to above Figure 4A and Figure 6B In the process of preparing the embankment, the photoresist PR is coated two or more times on the metal layer for forming the first electrode 310.

[0215] The width of the fourth embankment layer 410-2 can be achieved by: applying different shapes of masks in the process of preparing the embankment referred to above Figure 4A and Figure 6B The mask is used to expose the photoresist PR coated on the metal layer for forming the first electrode 310.

[0216] Figure 14 FIG. is a cross-sectional view showing another example of the shape of the embankment according to another exemplary embodiment of the present disclosure.

[0217] As Figure 14 shown, the shape of the first embankment layer 410-1 included in the embankment 400 can be the same as or similar to the shape of the first embankment layer 410 referred to above Figure 8 described. In addition, the shape of the fourth embankment layer 410-2 included in the embankment 400 can be the same as or similar to the shape of the fourth embankment layer 410-2 referred to above Figure 13 described.

[0218] Herein, as Figure 14 shown, the difference between the maximum height portion of the first embankment layer 410-1 and the maximum height portion of the fourth embankment layer 410-2 can be the second height hd2.

[0219] For example, the second height hd2 can be equal to or greater than the height of the first embankment layer 410 referred to above Figure 8 described. The second height hd2 can be similar to or the same as the first height hd1 referred to above Figure 13 described.

[0220] In addition, the fourth embankment layer 410-2 can have the same or similar width as the first embankment layer 410-1.

[0221] Figure 15 FIG. is a cross-sectional view showing yet another example of the shape of the embankment according to another exemplary embodiment of the present disclosure.

[0222] As Figure 15 shown, the shape of the first embankment layer 410-1 included in the embankment 400 can be the same as or similar to the shape of the first embankment layer 410 referred to above Figure 9 described. In addition, the shape of the fourth embankment layer 410-2 included in the embankment 400 can be the same as or similar to the shape of the fourth embankment layer 410-2 referred to above Figure 13The shapes of the described fourth embankment layer 410-2 are the same or similar.

[0223] In this document, as Figure 15 shown, the difference between the maximum height portion of the first embankment layer 410-1 and the maximum height portion of the fourth embankment layer 410-2 can be the third height hd3.

[0224] For example, the third height hd3 can be less than the height of the first embankment layer 410 described above with reference to Figure 9 The third height hd3 can be less than the first height hd1 and the second height hd2 respectively described above with reference to Figure 13 and Figure 14 described.

[0225] In addition, the fourth embankment layer 410-2 can have a width larger than that of the first embankment layer 410-1.

[0226] Figure 16 is a cross-sectional view showing another example of the shape of the embankment according to another exemplary embodiment of the present disclosure.

[0227] As Figure 16 shown, the shape of the first embankment layer 410-1 included in the embankment 400 can be the same as or similar to the shape of the first embankment layer 410 described above with reference to Figure 10 In addition, the shape of the fourth embankment layer 410-2 included in the embankment 400 can be the same as or similar to the shape of the fourth embankment layer 410-2 described above with reference to Figure 13 described.

[0228] In this document, as Figure 16 shown, the difference between the maximum height portion of the first embankment layer 410-1 and the maximum height portion of the fourth embankment layer 410-2 can be the fourth height hd4.

[0229] For example, the fourth height hd4 can be less than the height of the first embankment layer 410 described above with reference to Figure 10 The fourth height hd4 can be less than the first height hd1 and the second height hd2 respectively described above with reference to Figure 13 and Figure 14 described.

[0230] In addition, the fourth embankment layer 410-2 can have a width larger than that of the first embankment layer 410-1.

[0231] Figure 17 is a cross-sectional view showing another example of the shape of the embankment according to another exemplary embodiment of the present disclosure.

[0232] As Figure 17 shown, the shape of the first embankment layer 410-1 included in the embankment 400 can be the same as or similar to the shape of the first embankment layer 410 described above with reference to Figure 11The shape of the described first bank layer 410 is the same or similar. Additionally, the shape of the fourth bank layer 410-2 included in the bank 400 may be the same or similar to the shape of the fourth bank layer 410-2 described above with reference to Figure 13 The shape of the described fourth bank layer 410-2 is the same or similar.

[0233] In this document, as Figure 17 shown, the difference between the maximum height portion of the first bank layer 410-1 and the maximum height portion of the fourth bank layer 410-2 may be the fifth height hd5.

[0234] For example, the fifth height hd5 may be less than the height of the first bank layer 410 described above with reference to Figure 11 The fifth height hd5 may be less than the first height hd1 and the second height hd2 described above with reference to Figure 13 and Figure 14 respectively.

[0235] Additionally, the fourth bank layer 410-2 may have a greater width than the first bank layer 410-1.

[0236] Using the bank 400 having various shapes described above with reference to Figures 7 to 17 the reliability of the display device 100 can be improved by suppressing oxidation and contamination of the surface of the first electrode 310 in the light-emitting element 300. In addition, the slope of the bank adjacent to the emission region of the sub-pixel can be selectively adjusted. Accordingly, a low-reflection structure of the light-emitting element can be ensured, and an excessive light leakage current (LLC) flowing to the boundary between the light-emitting elements can also be suppressed. As described above, the potential probability of defects, such as contamination or oxidation, of the display device can be minimized. Accordingly, the lifespan of the display device can be improved, and thus the production energy can be reduced, thereby achieving low-power driving.

[0237] Exemplary embodiments of the present disclosure may also be described as follows:

[0238] According to an aspect of the present disclosure, a display device is provided. The display device includes a substrate including a display region in which a plurality of pixels are defined and a non-display region that does not overlap with the display region. The display device also includes a plurality of light-emitting elements, each of the plurality of light-emitting elements including a first electrode, an emission layer, and a second electrode that are sequentially stacked on the substrate and in the display region. The display device also includes a bank disposed on the substrate and covering an end point of the first electrode. At least a portion of the bank includes: a first bank layer that contacts the end point of the first electrode and includes an inner portion in a direction toward the first electrode and an outer portion opposite to the inner portion based on a vertical line passing through the maximum height portion; a second bank layer disposed to contact the outer portion of the first bank layer; and a third bank layer disposed on the second bank layer. The second bank layer is surrounded by at least one of the first bank layer and the third bank layer.

[0239] The endpoints of the second embankment layer can be in contact with the outer portion of the first embankment layer, and the endpoints of the third embankment layer can be in contact with the outer portion of the first embankment layer.

[0240] The height of the second embankment layer in the contact portion between the first embankment layer and the second embankment layer can be less than the maximum height of the first embankment layer, and the height of the third embankment layer in the contact portion between the first embankment layer and the third embankment layer can be less than the maximum height of the first embankment layer.

[0241] The first embankment layer can have an asymmetric shape, and the inner portion of the first embankment layer can have a steeper slope than the outer portion.

[0242] The endpoints of the second embankment layer can be in contact with the outer portion of the first embankment layer, and the third embankment layer can cover at least a portion of the upper surface of the first embankment layer.

[0243] The endpoints of the second embankment layer and the endpoints of the third embankment layer can be in contact with the upper surface of the first embankment layer.

[0244] The heights of the second embankment layer and the third embankment layer can gradually decrease as they approach the first embankment layer.

[0245] The maximum height of the portion where the second embankment layer overlaps with the first embankment layer can be set to be greater than the maximum height of the portion where the second embankment layer does not overlap with the first embankment layer. The maximum height of the portion where the third embankment layer overlaps with the first embankment layer can be set to be greater than the maximum height of the portion where the third embankment layer does not overlap with the first embankment layer.

[0246] The first embankment layer can have an asymmetric shape. The maximum height portion of the first embankment layer can be located in a region opposite to the region where the first electrode is provided, based on the center line of the first embankment layer in the vertical direction.

[0247] The second embankment layer and the third embankment layer can cover all of the outer portion of the first embankment layer and a part of the inner portion.

[0248] The third embankment layer can completely cover the first embankment layer.

[0249] Another portion of the embankment can further include a fourth embankment layer that is in contact with the endpoints of the first electrode and has a height greater than that of the first embankment layer. The fourth embankment layer can include an inner portion in the direction towards the first electrode and an outer portion opposite to the inner portion, based on a vertical line passing through the maximum height portion of the fourth embankment layer. In another portion of the embankment, the second embankment layer can cover a part of the inner portion and the outer portion of the fourth embankment layer. The third embankment layer can completely cover the second embankment layer and the fourth embankment layer.

[0250] The fourth embankment layer can be made of the same material as the first embankment layer and be provided on the same layer as the first embankment layer.

[0251] The fourth bank layer may have a width greater than that of the first bank layer.

[0252] The first bank layer and the third bank layer may be made of the same material.

[0253] Each of the first bank layer and the third bank layer may be made of a transparent material, and the second bank layer may contain a black material.

[0254] The display device may further include: a thin film transistor disposed on a substrate and electrically connected to the light-emitting element; an insulating layer disposed on the thin film transistor; a planarization layer disposed on the insulating layer; and a encapsulation layer covering the light-emitting element and the bank. The first electrode, the first bank layer, and the second bank layer are disposed on the planarization layer.

[0255] The display device may further include: a touch buffer layer disposed on the encapsulation layer; a plurality of touch electrodes disposed on the touch buffer layer; and a touch electrode protection layer disposed on the plurality of touch electrodes. The touch electrodes overlap the bank.

[0256] The display device may further include: a light-shielding layer disposed on the encapsulation layer and including an opening overlapping the light-emitting element; a color filter disposed on the light-shielding layer and filling the opening of the light-shielding layer; and a coating layer covering the color filter. The light-shielding layer overlaps the bank.

[0257] Each of the first bank layer, the second bank layer, and the third bank layer may be made of an organic material.

[0258] Although the exemplary embodiments of the present disclosure have been described in detail with reference to the accompanying drawings, the present disclosure is not limited thereto and can be embodied in many different forms without departing from the technical concept of the present disclosure. Therefore, the exemplary embodiments of the present disclosure are provided for illustrative purposes only and are not intended to limit the technical concept of the present disclosure. The scope of the technical concept of the present disclosure is not limited thereto. Therefore, it should be understood that the above exemplary embodiments are illustrative in all respects and do not limit the present disclosure. The protection scope of the present disclosure should be construed based on the appended claims, and all technical concepts within the equivalent scope thereof should be construed as falling within the scope of the present disclosure.

Claims

1. A display device, comprising: a substrate including a display area in which a plurality of pixels are defined and a non-display area that does not overlap with the display area; A plurality of light-emitting elements, each of which includes a first electrode, an emission layer, and a second electrode sequentially stacked on the substrate and in the display area; as well as a bank, the bank being disposed on the substrate and covering an end point of the first electrode, Wherein, at least a portion of the embankment comprises: a first bank layer contacting an end point of the first electrode and including: an inner portion in a direction toward the first electrode based on a vertical line passing through a maximum height portion of the first bank layer, and an outer portion opposite to the inner portion; a second bank layer disposed in contact with the outer portion of the first bank layer; and a third bank layer, the third bank layer being disposed on the second bank layer, and The second bank layer is surrounded by at least one of the first bank layer and the third bank layer.

2. The display device according to claim 1, wherein: An end point of the second bank layer contacts the outer portion of the first bank layer, and An end point of the third bank layer contacts the outer portion of the first bank layer.

3. The display device according to claim 2, wherein: A height of the second bank layer in a contact portion between the first bank layer and the second bank layer is smaller than a maximum height of the first bank layer, and A height of the third bank layer in a contact portion between the first bank layer and the third bank layer is smaller than a maximum height of the first bank layer.

4. The display device according to claim 2, wherein: The first bank layer has an asymmetric shape, and The inner portion of the first bank has a steeper slope than the outer portion.

5. The display device according to claim 1, wherein: An end point of the second bank layer contacts the outer portion of the first bank layer, and The third bank layer covers at least a portion of an upper surface of the first bank layer.

6. The display device according to claim 1, wherein: An end point of the second bank layer and an end point of the third bank layer contact an upper surface of the first bank layer.

7. The display device according to claim 6, wherein: The heights of the second bank layer and the third bank layer gradually decrease as they approach the first bank layer.

8. The display device according to claim 6, wherein: A maximum height of a portion of the second bank layer overlapping the first bank layer is set to be greater than a maximum height of a portion of the second bank layer not overlapping the first bank layer, and A maximum height of a portion of the third bank layer overlapping the first bank layer is set to be greater than a maximum height of a portion of the third bank layer not overlapping the first bank layer.

9. The display device according to claim 1, wherein: The first bank layer has an asymmetric shape, and A maximum height portion of the first bank layer is located in a region opposite to a region where the first electrode is disposed based on a center line of the first bank layer in a vertical direction.

10. The display device according to claim 9, wherein: The second bank layer and the third bank layer cover the entirety of the outer portion and a portion of the inner portion of the first bank layer.

11. The display device according to claim 9, wherein: The third bank layer completely covers the first bank layer.

12. The display device according to claim 1, wherein: The other part of the bank further includes a fourth bank layer, the fourth bank layer contacts an end point of the first electrode and has a height greater than that of the first bank layer, The fourth bank layer includes an inner portion in a direction toward the first electrode based on a vertical line passing through a maximum height portion of the fourth bank layer, and an outer portion opposite to the inner portion, and In another part of the dike, The second bank layer covers a portion of the inner portion and the outer portion of the fourth bank layer, and The third bank layer completely covers the second bank layer and the fourth bank layer.

13. The display device according to claim 12, wherein: The fourth bank layer is made of the same material as the first bank layer and is disposed on the same layer as the first bank layer.

14. The display device according to claim 12, wherein: The fourth bank layer has a width greater than that of the first bank layer.

15. The display device according to claim 1, wherein: The first bank layer and the third bank layer are made of the same material.

16. The display device according to claim 1, wherein: Each of the first bank layer and the third bank layer is made of a transparent material, and The second bank layer includes a black material.

17. The display device according to claim 1, further comprising: a thin film transistor disposed on the substrate and electrically connected to the light emitting element; an insulating layer disposed on the thin film transistor; a planarization layer disposed on the insulating layer; as well as an encapsulation layer covering the light emitting element and the bank, Wherein, the first electrode, the first bank layer and the second bank layer are arranged on the planarization layer.

18. The display device according to claim 17, further comprising: a touch buffer layer disposed on the encapsulation layer; A plurality of touch electrodes disposed on the touch buffer layer; as well as a touch electrode protection layer provided on the plurality of touch electrodes, Wherein, the touch electrode overlaps with the dam.

19. The display device according to claim 17, further comprising: a light shielding layer, the light shielding layer being disposed on the encapsulation layer and comprising an opening overlapping the light emitting element; a color filter, the color filter being disposed on the light shielding layer and filling the opening of the light shielding layer; as well as a coating layer, the coating layer covering the color filter, Wherein, the light shielding layer overlaps with the dam.

20. The display device according to claim 1, wherein: Each of the first bank layer, the second bank layer, and the third bank layer is made of an organic material.

21. A display device, comprising: a substrate including a display area having a plurality of pixels defined therein; A plurality of light-emitting elements, each of which includes a first electrode, an emission layer, and a second electrode sequentially stacked on the substrate and in the display area; as well as a bank disposed on the substrate and partially overlapping the first electrode, Wherein, at least a portion of the embankment comprises: a first bank layer, the first bank layer partially overlapping the first electrode; a second bank layer, the second bank layer being disposed to partially overlap with the first bank layer and not overlap with the first electrode; and a third bank layer, the third bank layer being disposed on the second bank layer, and The second bank layer is surrounded by at least one of the first bank layer and the third bank layer.

22. The display device according to claim 21, wherein: The second bank layer includes a black material.

Images