Display device including light emitting device

Abstract

To provide a display apparatus for improving light extraction efficiency without reducing light emitting efficiency.SOLUTION: A light-emitting device may include a first electrode, a light-emitting layer, and a second electrode stacked in order on a planarization film of a light-emitting area. The planarization film may include at least one flat groove or at least one planarization protruding portion overlapping with the light-emitting area. The first electrode, the light-emitting layer, and the second electrode of the light-emitting device may extend over a side surface of the flat groove or a side surface of the planarization protruding portion. Between the first electrode and the light-emitting layer positioned over the side surface of the flat groove or the side surface of the planarization protruding portion, an insulation pattern may be positioned. Thereby, a display apparatus may improve light extraction efficiency without reducing light emitting efficiency.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to display devices in which light emitting elements are located within each pixel area. [Background technology]

[0002] Generally, a display device provides an image to a user. For example, the display device may include a plurality of pixel regions. Each pixel region may embody a particular color. For example, a light emitting element may be located within each pixel region. The light emitting element may emit light representing a particular color. For example, the light emitting element may include a light emitting layer located between a first electrode and a second electrode.

[0003] In a display device, the light emitting element in each pixel region may be located on the flat plane of the planarization film. As a result, the brightness of the display device may decrease rapidly as the viewing angle increases. In addition, the light extraction efficiency of the display device may decrease due to total reflection occurring between the first and second electrodes. Summary of the Invention [Problem to be solved by the invention]

[0004] SUMMARY OF THE PRESENTLY PREFERRED EMBODIMENTS An object of the present invention is to provide a display device capable of improving light extraction efficiency.

[0005] Another object of the present invention is to provide a display device capable of reducing a decrease in luminance caused by an increase in the viewing angle.

[0006] The problems to be solved by the present invention are not limited to the problems mentioned above. Problems not mentioned here will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0007] A display device according to the technical idea of ​​the present invention for achieving the problem to be solved includes an element substrate. A bank insulating film is positioned on the element substrate. The bank insulating film defines an emission region within a pixel region. A planarization film is positioned between the element substrate and the bank insulating film. The planarization film includes a flat protrusion overlapping the emission region. A side surface of the flat protrusion has a concave shape. An insulating pattern is positioned on a side surface of the flat protrusion. The insulating pattern is spaced apart from an upper surface of the flat protrusion. A light emitting element is positioned on the planarization film in the emission region. The light emitting element includes a first electrode, an emission layer and a second electrode stacked in sequence. The insulating pattern is positioned between the first electrode and the emission layer of the light emitting element.

[0008] The planar shape of the flat protrusion may be polygonal.

[0009] The insulating pattern may include the same material as the bank insulating film.

[0010] The bank insulating layer may be a linear layer having a constant thickness, and the thickness of the insulating pattern may be less than the thickness of the bank insulating layer.

[0011] The second electrode may have a greater reflectivity than the first electrode.

[0012] A color filter may be located between the device substrate and the planarization film. The color filter may overlap the light-emitting region.

[0013] The planarizing film may include a planar groove surrounding the planar protrusion.

[0014] The width of the flat groove may be less than the width of the flat protrusion.

[0015] In order to achieve another object of the present invention, a display device according to the technical concept of the present invention includes an element substrate. A planarization film is positioned on the element substrate. The planarization film includes a flat groove. A first electrode and a bank insulating film are positioned on the planarization film. The first electrode covers the side and bottom of the flat groove. An insulating pattern is positioned on a portion of the first electrode covering the side of the flat groove. The bank insulating film is positioned outside the flat groove. The bank insulating film covers an end of the first electrode. An emission layer is positioned on a portion of the first electrode exposed by the bank insulating film. A second electrode is positioned on the emission layer. The second electrode extends onto the bank insulating film.

[0016] The sides of the flat groove may have a convex shape.

[0017] The insulating pattern may be spaced from the bottom surface of the planar groove.

[0018] The planar shape of the flat groove may be polygonal.

[0019] The transmittance of the second electrode may be greater than the transmittance of the first electrode.

[0020] A sealing unit may be disposed on the second electrode. The sealing unit may have a laminated structure of an inorganic insulating film made of an inorganic insulating material and an organic insulating film made of an organic insulating material.

[0021] The planarization film may include a flat protrusion that overlaps the light-emitting region. The width of the flat protrusion may be smaller than the width of the flat groove. Effect of the Invention

[0022] The display device according to the technical concept of the present invention includes a planarization film including a flat groove or a flat protrusion and a light emitting element located on the planarization film, and a first electrode, a light emitting layer, and a second electrode of the light emitting element may extend onto a side surface of the flat groove or a side surface of the flat protrusion, and the first electrode and the light emitting layer may be separated by an insulating pattern on the side surface of the flat groove or the side surface of the flat protrusion. As a result, the display device according to the technical concept of the present invention may improve light extraction efficiency without reducing light emission efficiency. Therefore, the display device according to the technical concept of the present invention may reduce power required for the operation of each pixel region. That is, the display device according to the technical concept of the present invention may reduce power consumption by low power driving. In addition, the display device according to the technical concept of the present invention may mitigate brightness reduction due to an increase in viewing angle. [Brief description of the drawings]

[0023] [Figure 1] 1 is a schematic diagram illustrating a display device according to an embodiment of the present invention. [Diagram 2] 2 is a diagram showing a circuit of a unit pixel area in a display device according to an embodiment of the present invention; [Diagram 3] 2 is a plan view showing a light emitting region in a display device according to an embodiment of the present invention; [Figure 4] FIG. 4 is a cross-sectional view taken along line II' in FIG. [Diagram 5] FIG. 5 is an enlarged view of the K1 region in FIG. [Figure 6] 1A to 1C are diagrams sequentially illustrating a method of forming a display device according to an embodiment of the present invention. [Figure 7] 1A to 1C are diagrams sequentially illustrating a method of forming a display device according to an embodiment of the present invention. [Figure 8] 1A to 1C are diagrams sequentially illustrating a method of forming a display device according to an embodiment of the present invention. [Figure 9] 1A to 1C are diagrams sequentially illustrating a method of forming a display device according to an embodiment of the present invention. [Figure 10]1A to 1C are diagrams sequentially illustrating a method of forming a display device according to an embodiment of the present invention. [Figure 11] 1A to 1C are diagrams sequentially illustrating a method of forming a display device according to an embodiment of the present invention. [Figure 12A] 13 is a plan view showing a light emitting region in a display device according to another embodiment of the present invention; FIG. [Figure 12B] 13 is a plan view showing a light emitting region in a display device according to another embodiment of the present invention; FIG. [Figure 12C] 13 is a plan view showing a light emitting region in a display device according to another embodiment of the present invention; FIG. [Figure 12D] 13 is a plan view showing a light emitting region in a display device according to another embodiment of the present invention; FIG. [Figure 12E] 13 is a plan view showing a light emitting region in a display device according to another embodiment of the present invention; FIG. [Figure 13] 11 is a cross-sectional view showing a pixel region in a display device according to another embodiment of the present invention. [Figure 14] FIG. 14 is an enlarged view of the K2 region in FIG. [Figure 15] 10A to 10C are diagrams sequentially illustrating a method of forming a display device according to another embodiment of the present invention. [Figure 16] 10A to 10C are diagrams sequentially illustrating a method of forming a display device according to another embodiment of the present invention. [Figure 17] 10A to 10C are diagrams sequentially illustrating a method of forming a display device according to another embodiment of the present invention. [Figure 18] 10A to 10C are diagrams sequentially illustrating a method of forming a display device according to another embodiment of the present invention. [Figure 19] 10A to 10C are diagrams sequentially illustrating a method of forming a display device according to another embodiment of the present invention. [Figure 20] 1 is a diagram illustrating a display device according to another embodiment of the present invention. [Figure 21] 1 is a diagram illustrating a display device according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] The purpose, technical configuration, and effects of the present invention will be more clearly understood from the following detailed description taken in conjunction with the drawings illustrating the embodiments of the present invention. The embodiments of the present invention are provided to fully convey the technical idea of ​​the present invention to those skilled in the art, and therefore the present invention is not limited to the embodiments described below and may be embodied in other forms.

[0025] In addition, parts denoted by the same reference numerals throughout the specification refer to the same components, and in the drawings, the length and thickness of layers or regions may be exaggerated for convenience. Note that when a first component is described as being "on" a second component, this includes not only the first component being directly in contact with the second component, but also the case where a third component is located between the first and second components.

[0026] Here, the terms "first" and "second" are used to describe various components and to distinguish one component from another, provided that the first component and the second component may be arbitrarily named according to the convenience of those skilled in the art without departing from the technical spirit of the present invention.

[0027] The terms used in the present specification are merely used to describe specific embodiments and are not intended to limit the present invention. For example, a component expressed in the singular includes a plurality of components unless the context clearly indicates the singular component alone. In addition, in the present specification, the terms "include" or "have" are intended to specify the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, and should be understood not to preclude the presence or additional possibility of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0028] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the present invention belongs. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning they have in the context of the relevant art, and should not be interpreted in an ideal or overly formal sense unless expressly defined in the specification of the present invention.

[0029] (Example) 1 is a schematic diagram of a display device according to an embodiment of the present invention, and FIG 2 is a diagram showing a circuit of a unit pixel area in the display device according to an embodiment of the present invention.

[0030] 1 and 2, a display device according to an embodiment of the present invention may include a display panel DP. The display panel DP may generate an image to be provided to a user. For example, the display panel DP may include a plurality of pixel areas PA.

[0031] Various signals may be provided to each pixel area PA through signal wirings GL, DL, PL, and RL. For example, the signal wirings GL, DL, PL, and RL may include a gate line GL for sequentially applying gate signals to each pixel area PA, a data line DL for applying data signals to each pixel area PA, a power supply voltage supply line PL for supplying a power supply voltage to each pixel area PA, and a reference voltage supply line RL for supplying a reference voltage to each pixel area PA. The gate line GL may be electrically connected to a gate driver GD. The data line DL may be electrically connected to a data driver DD. The gate driver GD and the data driver DD may be controlled by a timing controller TC. For example, the gate driver GD may receive a clock signal, a reset signal, and a start signal from the timing controller TC, and the data driver DD may receive digital video data and a source timing signal from the timing controller TC. The power supply voltage supply line PL and the reference voltage supply line RL may be electrically connected to a power supply unit PU.

[0032] The display panel DP may include a display area AA in which the pixel area PA is located, and a bezel area BZ located outside the display area AA. At least one of the gate driver GD, the data driver DD, the timing controller TC, and the power supply unit PU may be located on the bezel area BZ of the display panel DP. For example, a display device according to an embodiment of the present invention may be a GIP (Gate In Panel) type display device in which the gate driver GD is formed on the bezel area BZ of the display panel DP.

[0033] Each pixel area PA may embody a specific color. For example, a light emitting element 300 electrically connected to a pixel driving circuit DC may be located within each pixel area PA. The pixel driving circuit DC and the light emitting element 300 of each pixel area PA may be located on a device substrate 100. The device substrate 100 may include an insulating material. The device substrate 100 may include a transparent material. For example, the device substrate 100 may include glass or plastic.

[0034] The pixel driving circuit DC of each pixel area PA may supply a driving current corresponding to a data signal to the light emitting element 300 of the corresponding pixel area PA for one frame in response to a gate signal. For example, the pixel driving circuit DC of each pixel area PA may include a first thin film transistor T1, a second thin film transistor T2, a third thin film transistor T3 and a storage capacitor Cst.

[0035] Fig. 3 is a plan view of a light emitting region in a display device according to an embodiment of the present invention, Fig. 4 is a cross-sectional view taken along line II' in Fig. 3, and Fig. 5 is an enlarged view of region K1 in Fig. 4.

[0036] 2 to 5, the first thin film transistor T1 of each pixel area PA may include a first semiconductor pattern, a first gate insulating film, a first gate electrode, a first drain electrode, and a first source electrode. The first thin film transistor T1 of each pixel area PA may transmit a data signal to the second thin film transistor T2 of the corresponding pixel area PA according to a gate signal. For example, the first thin film transistor T1 of each pixel area PA may be a switching thin film transistor. The first gate electrode may be electrically connected to one of the gate lines GL. The first drain electrode may be electrically connected to one of the data lines DL.

[0037] The second thin film transistor T2 of each pixel area PA may include a second semiconductor pattern 210, a second gate insulating film 220, a second gate electrode 230, a second drain electrode 240, and a second source electrode 250. The second thin film transistor T2 of each pixel area PA may generate a driving current corresponding to a data signal. For example, the second thin film transistor T2 of each pixel area PA may be a driving thin film transistor. The second gate electrode 230 may be electrically connected to the first source electrode. The second drain electrode 240 may be electrically connected to one of the power supply lines PL.

[0038] The second semiconductor pattern 210 may be located on the device substrate 100. The second semiconductor pattern 210 may include a drain region 210d, a channel region 210c, and a source region 210s. The channel region 210c may be located between the drain region 210d and the source region 210s. The drain region 210d and the source region 210s may have a smaller resistance than the channel region 210c. The drain region 210d and the source region 210s may have a multi-layer structure. The source region 210s may have the same layer structure as the drain region 210d. For example, the drain region 210d may have a layer structure of a first drain layer 211d and a second drain layer 212d, and the source region 210s may have a layer structure of a first source layer 211s and a second source layer 212s.

[0039] The first drain layer 211d and the first source layer 211s may be located on the same layer as the channel region 210c. The channel region 210c, the first drain layer 211d, and the first source layer 211s may include a semiconductor material. For example, the channel region 210c, the first drain layer 211d, and the first source layer 211s may include an oxide semiconductor such as IGZO. The first drain layer 211d and the first source layer 211s may include the same material as the channel region 210c. The first drain layer 211d and the first source layer 211s may have the same resistance as the channel region 210c. For example, the channel region 210c, the first drain layer 211d, and the first source layer 211s may be a non-conductive region of an oxide semiconductor. The first drain layer 211d and the first source layer 211s may be formed simultaneously with the channel region 210c.

[0040] The channel region 210c may be in direct contact with the first drain layer 211d and the first source layer 211s. The channel region 210c may be physically connected to the first drain layer 211d and the first source layer 211s. For example, an interface between the first drain layer 211d and the channel region 210c and an interface between the channel region 210c and the first source layer 211s may not be recognized. Thus, in the display device according to the embodiment of the present invention, the internal resistance of the second semiconductor pattern 210 may be minimized.

[0041] The second drain layer 212d may be located on the first drain layer 211d. For example, the first drain layer 211d may be located between the element substrate 100 and the second drain layer 212d. The second drain layer 212d may be in direct contact with the first drain layer 211d. For example, the lower surface of the second drain layer 212d facing the element substrate 100 may be in direct contact with the upper surface of the first drain layer 211d facing the element substrate 100. The second source layer 212s may be located on the first source layer 211s. For example, the first source layer 211s may be located between the element substrate 100 and the second source layer 212s. The second source layer 212s may be in direct contact with the first source layer 211s. For example, the lower surface of the second source layer 212s facing the element substrate 100 may be in direct contact with the upper surface of the first source layer 211s facing the element substrate 100. Therefore, in the display device according to the embodiment of the present invention, the resistance of the drain region 210d and the resistance of the source region 210s may be minimized.

[0042] The second drain layer 212d and the second source layer 212s may include a different material from the channel region 210c, the first drain layer 211d, and the first source layer 211s. The second drain layer 212d and the second source layer 212s may have a smaller resistance than the channel region 210c, the first drain layer 211d, and the first source layer 211s. For example, the second drain layer 212d and the second source layer 212s may include a conductive oxide or metal, such as ITO and IZO. Thus, in the display device according to the embodiment of the present invention, the resistance of the second drain region 210d and the resistance of the second source region 210s may be minimized. The second source layer 212s may include the same material as the second drain layer 212d. For example, the second source layer 212s may be formed simultaneously with the second drain layer 212d. The second drain layer 212d and the second source layer 212s may be located outside the channel region 210c. For example, the process of forming the second semiconductor pattern 210 may include the steps of forming a semiconductor material layer on the device substrate 100, forming a low-resistance material layer on the semiconductor material layer, patterning the semiconductor material layer and the low-resistance material layer, and removing a portion of the low-resistance material layer overlapping the channel region 210c. Therefore, in the display device according to the embodiment of the present invention, the efficiency of the process of forming the second semiconductor pattern 210 may be improved.

[0043] The first semiconductor pattern may have the same structure as the second semiconductor pattern 210. For example, the first semiconductor pattern may include a channel region located between a drain region and a source region, and the drain region and the source region may have a stacked structure of a first layer containing the same material as the channel region and a second layer having a lower resistance than the first layer. The first semiconductor pattern may be formed simultaneously with the second semiconductor pattern 210. For example, the channel region 210c of the second semiconductor pattern 210 may have the same resistance as the channel region of the first semiconductor pattern. As a result, the process efficiency of the display device according to the technical idea of ​​the present invention may be effectively improved.

[0044] The second gate insulating layer 220 may be located on the channel region 210c of the second semiconductor pattern 210. The drain region 210d and the source region 210s of the second semiconductor pattern 210 may be located outside the second gate insulating layer 220. For example, the second gate insulating layer 220 may be located between the second drain layer 212d and the second source layer 212s. The second gate insulating layer 220 may include an insulating material. For example, the second gate insulating layer 220 may be an inorganic insulating layer made of an inorganic insulating material such as silicon oxide (SiOx) and silicon nitride (SiNx).

[0045] The first gate insulating layer may include the same material as the second gate insulating layer 220. For example, the second gate insulating layer 220 may be formed simultaneously with the first gate insulating layer. The thickness of the first gate insulating layer may be the same as the thickness of the second gate insulating layer 220.

[0046] The second gate electrode 230 may be located on the second gate insulating layer 220. For example, the second gate electrode 230 may overlap the channel region 210c of the second semiconductor pattern 210. The second gate electrode 230 may be insulated from the second semiconductor pattern 210 by the second gate insulating layer 220. For example, a side surface of the second gate electrode 230 may be continuous with a side surface of the second gate insulating layer 220. The second gate electrode 230 may include a conductive material. For example, the second gate electrode 230 may include a metal such as aluminum (Al), chromium (Cr), copper (Cu), molybdenum (Mo), titanium (Ti), and tungsten (W). The channel region 210c of the second semiconductor pattern 210 may have an electrical conductivity corresponding to a voltage applied to the second gate electrode 230.

[0047] The first gate electrode may include the same material as the second gate electrode 230. For example, the second gate electrode 230 may be formed simultaneously with the first gate electrode. A side surface of the first gate electrode may be continuous with a side surface of the first gate insulating film. For example, a source region of the first semiconductor pattern may be electrically connected to a drain region of the first semiconductor pattern by a voltage applied to the first gate electrode.

[0048] The second drain electrode 240 may include a conductive material. For example, the second drain electrode 240 may include a metal such as aluminum (Al), chromium (Cr), copper (Cu), molybdenum (Mo), titanium (Ti), and tungsten (W). The second drain electrode 240 may include the same material as the second gate electrode 230. For example, the second drain electrode 240 may be formed simultaneously with the second gate electrode 230. The second drain electrode 240 may be located on the same layer as the second gate electrode 230. The second drain electrode 240 may be separated from the second gate electrode 230. The second drain electrode 240 may be insulated from the second gate electrode 230. The second drain electrode 240 may be electrically connected to the drain region 210d of the second semiconductor pattern 210. For example, the second drain electrode 240 may be in direct contact with the second drain layer 212d of the second semiconductor pattern 210.

[0049] The second source electrode 250 may include a conductive material. For example, the second source electrode 250 may include a metal such as aluminum (Al), chromium (Cr), copper (Cu), molybdenum (Mo), titanium (Ti), and tungsten (W). The second source electrode 250 may include the same material as the second drain electrode 240. For example, the second source electrode 250 may be formed simultaneously with the second drain electrode 240. The second source electrode 250 may be located on the same layer as the second drain electrode 240. The second source electrode 250 may be separated from the second gate electrode 230 and the second drain electrode 240. The second source electrode 250 may be insulated from the second gate electrode 230. The second source electrode 250 may be electrically connected to the source region 210s of the second semiconductor pattern 210. For example, the second source electrode 250 may be in direct contact with the second source layer 212s of the second semiconductor pattern 210.

[0050] The first drain electrode and the first source electrode may comprise the same material as the second drain electrode 240 and the second source electrode 250. The first drain electrode and the first source electrode may be located on the same layer as the second drain electrode 240 and the second source electrode 250. For example, the second drain electrode 240 and the second source electrode 250 may be formed simultaneously with the first drain electrode and the first source electrode. The first drain electrode and the first source electrode may comprise the same material as the first gate electrode.

[0051] The third thin film transistor T3 of each pixel area PA may include a third semiconductor pattern, a third gate insulating film, a third gate electrode, a third drain electrode, and a third source electrode. The third thin film transistor T3 of each pixel area PA may initialize the storage capacitor Cst of the corresponding pixel area PA according to a gate signal. For example, the third thin film transistor T3 of each pixel area PA may be located between the storage capacitor Cst of the corresponding pixel area PA and one of the reference voltage supply lines RL. The storage capacitor Cst of each pixel area PA may be supplied with a reference voltage according to the gate signal. For example, the third thin film transistor T3 of each pixel area PA may be a switching thin film transistor. The third gate electrode may be electrically connected to one of the gate lines GL. The third drain electrode may be electrically connected to one of the reference voltage supply lines RL. The first gate electrode and the third gate electrode of each pixel area PA may be electrically connected to the same gate line GL. For example, the third thin film transistor T3 of each pixel area PA may be turned on / off simultaneously with the first thin film transistor T1 of the corresponding pixel area PA.

[0052] The third thin film transistor T3 of each pixel region PA may be formed simultaneously with the first thin film transistor T1 of the corresponding pixel region PA. For example, the third semiconductor pattern may be formed to have the same structure as the first semiconductor pattern. The third gate insulating film may include the same material as the first gate insulating film. The third gate electrode, the third drain electrode, and the third source electrode may be formed simultaneously with the first gate electrode, the first drain electrode, and the first source electrode. As a result, the process efficiency of the display device according to the embodiment of the present invention may be improved.

[0053] The storage capacitor Cst of each pixel area PA may maintain a signal applied to the second gate electrode 230 of the second thin film transistor T2 located in the corresponding pixel area PA for one frame. For example, the storage capacitor Cst of each pixel area PA may be electrically connected between the second gate electrode 230 and the second source electrode 250 of the second thin film transistor T2 located in the corresponding pixel area PA. The storage capacitor Cst of each pixel area PA may have a stacked structure of capacitor electrodes. For example, the storage capacitor Cst of each pixel area PA may include a first capacitor electrode electrically connected to the second gate electrode 230 of the corresponding pixel area PA and a second capacitor electrode electrically connected to the second source electrode 250 of the corresponding pixel area PA. The third source electrode of the third thin film transistor T3 located in each pixel area PA may be connected to the same capacitor electrode as the second source electrode 250 of the corresponding pixel area PA. For example, the third source electrode of the third thin film transistor T3 located in each pixel area PA may be electrically connected to the second capacitor electrode of the storage capacitor Cst located in the corresponding pixel area PA.

[0054] A plurality of insulating layers 110, 120, 130, 140, and 150 for preventing unnecessary electrical connection within each pixel region PA may be disposed on the device substrate 100. For example, a device buffer layer 110, an interlayer insulating layer 120, a device protection layer 130, a planarization layer 140, and a bank insulating layer 150 may be disposed on the device substrate 100.

[0055] The device buffer film 110 may be located close to the device substrate 100. The device buffer film 110 may prevent contamination by the device substrate 100 during the process of forming the pixel driving circuit DC located in each pixel region PA. For example, the upper surface of the device substrate 100 facing the pixel driving circuit DC of each pixel region PA may be completely covered by the device buffer film 110. The pixel driving circuit DC of each pixel region PA may be located on the device buffer film 110. The device buffer film 110 may include an insulating material. For example, the device buffer film 110 may include an inorganic insulating material such as silicon oxide (SiOx) and silicon nitride (SiNx). The device buffer film 110 may have a multi-layer structure. For example, the device buffer film 110 may have a stacked structure of an inorganic insulating film made of silicon oxide (SiOx) and an inorganic insulating film made of silicon nitride (SiNx).

[0056] A light blocking pattern 105 may be located between the device substrate 100 and the pixel driving circuit DC of each pixel region PA. For example, the light blocking pattern 105 of each pixel region PA may be located between the device substrate 100 and the device buffer film 110. The second semiconductor pattern 210 of each pixel region PA may overlap with the light blocking pattern 105 of the corresponding pixel region PA. The light blocking pattern 105 may include a material capable of blocking light. For example, the light blocking pattern 105 may include a metal. Thus, in the display device according to the embodiment of the present invention, the external light traveling toward the second semiconductor pattern 210 of each thin film transistor T1, T2, T3 through the device substrate 100 may be blocked by the light blocking pattern 105. Therefore, in the display device according to the embodiment of the present invention, the characteristics of each thin film transistor T1, T2, T3 may be prevented from being changed due to the external light.

[0057] The light blocking pattern 105 may include a conductive material. A specific voltage may be applied to the light blocking pattern 105. For example, the light blocking pattern 105 of each pixel area PA may be electrically connected to the second source electrode 250 of the corresponding pixel area PA. As a result, in the display device according to the embodiment of the present invention, external light traveling toward the second semiconductor pattern 210 of each thin film transistor T1, T2, and T3 may be effectively blocked.

[0058] The interlayer insulating film 120 may be located on the device buffer film 110. The interlayer insulating film 120 may include an insulating material. For example, the interlayer insulating film 120 may be an inorganic insulating film made of an inorganic insulating material such as silicon oxide (SiOx) and silicon nitride (SiNx). The interlayer insulating film 120 may include the same material as the second gate insulating film 220 of each pixel region PA. The second gate insulating film 220 of each pixel region PA may be formed on the same layer as the interlayer insulating film 120. For example, the second drain electrode 240 and the second source electrode 250 of each pixel region PA may include a region located on the interlayer insulating film 120. The second source electrode 250 of each pixel region PA may directly contact the light blocking pattern 105 of the corresponding pixel region PA by penetrating the device buffer film 110 and the interlayer insulating film 120.

[0059] The device protection layer 130 may be disposed on the interlayer insulating layer 120. The device protection layer 130 may prevent damage to the pixel driving circuit DC disposed in each pixel region PA due to external moisture and impact. For example, the first drain electrode, the first source electrode, the second drain electrode 240, the second source electrode 250, the third drain electrode and the third source electrode of each pixel region PA may be covered by the device protection layer 130. The device protection layer 130 may include an insulating material. For example, the device protection layer 130 may be an inorganic insulating layer made of an inorganic insulating material such as silicon oxide (SiOx) and silicon nitride (SiNx).

[0060] The planarization film 140 may be located on the element protection film 130. The planarization film 140 may include an insulating material. The planarization film 140 may include the element protection film 130 and other materials. For example, the planarization film 140 may be an organic insulating film made of an organic insulating material. Steps due to the pixel driving circuits DC of each pixel area PA may be removed by the planarization film 140.

[0061] The planarization film 140 of each pixel region PA may include a plurality of flat protrusions 140p. Each flat protrusion 140p may be separated from an adjacent flat protrusion 140p. The plurality of flat protrusions 140p may be located side by side in the corresponding pixel region PA. Each flat protrusion 140p may be arranged alternately with an adjacent flat protrusion 140p. For example, the planar shape of each flat protrusion 140p may be a hexagon. The planarization film 140 of each pixel region PA may include a flat groove 140g located outside the flat protrusion 140p. The flat groove 140g may extend between the flat protrusions 140p. For example, the side surface 140s of each flat protrusion 140p may be a side surface of the flat groove 140g. The side surface 140s of each flat protrusion 140p may have a shape recessed toward the inside of the corresponding flat protrusion 140p. The planar groove 140g may have a side 140s that is convex toward an outer side of the planar groove 140g. A width of the planar groove 140g between adjacent planar protrusions 140p may be less than a width of each planar protrusion 140p.

[0062] The bank insulating film 150 may be located on the planarization film 140. The bank insulating film 150 may define a light emitting area EA in each pixel region PA. The planar protrusion 140p located on each pixel region PA may overlap the light emitting area EA defined in the corresponding pixel region PA by the bank insulating film 150. For example, the planar protrusion 140p and the planar groove 140g of each pixel region PA may be located in the light emitting area EA of the corresponding pixel region PA. The bank insulating film 150 may include an insulating material. For example, the bank insulating film 150 may be an inorganic insulating film made of an inorganic insulating material such as silicon oxide (SiOx) and silicon nitride (SiNx). The bank insulating film 150 may be a liner film (linear layer) having a certain thickness. For example, the bank insulating film 150 may extend along a side surface 140s of the planar protrusion 140p located near an edge of the light emitting area EA defined in each pixel region PA.

[0063] The light emitting element 300 of each pixel area PA may be located on the planarization film 140 of the light emitting area EA defined in the corresponding pixel area PA. The light emitting element 300 of each pixel area PA may emit light representing a specific color. For example, the light emitting element 300 of each pixel area PA may include a first electrode 310, a light emitting layer 320, and a second electrode 330 sequentially stacked on the planarization film 140 of the light emitting area EA defined in the corresponding pixel area PA.

[0064] The first electrode 310 may include a conductive material. The first electrode 310 may have a relatively high transmittance. For example, the first electrode 310 may be a transparent electrode made of a transparent conductive material such as ITO or IZO.

[0065] The light emitting layer 320 may generate light having a brightness corresponding to a voltage difference between the first electrode 310 and the second electrode 330. For example, the light emitting layer 320 may include an emission material layer (EML) including a light emitting material. The light emitting material may include an organic material, an inorganic material, or a hybrid material. For example, a display device according to an embodiment of the present invention may be an organic light emitting display device including an organic light emitting material.

[0066] The light emitting layer 320 may have a multi-layer structure. For example, the light emitting layer 320 may include at least one of a hole injection layer (HIL), a hole transport layer (HTL), an electron transport layer (ETL), and an electron injection layer (Electron Injection Layer (EIL)). This can improve the light emitting efficiency of the display device according to the embodiment of the present invention.

[0067] The second electrode 330 may include a conductive material. The second electrode 330 may include a material other than the first electrode 310. The reflectance of the second electrode 330 may be greater than the reflectance of the first electrode 310. For example, the second electrode 330 may include a metal such as aluminum (Al) or silver (Ag). Thus, in the display device according to the embodiment of the present invention, light generated by the light emitting layer 320 may be emitted through the first electrode 310.

[0068] The pixel driving circuit DC of each pixel area PA may be located outside the light emitting area EA defined in the corresponding pixel area PA. For example, the first thin film transistor T1, the second thin film transistor T2, the third thin film transistor T3 and the storage capacitor Cst of each pixel area PA may not overlap with the light emitting area EA of the corresponding pixel area PA. As a result, in the display device according to the embodiment of the present invention, the light emitted from the light emitting element 300 of each pixel area PA may not be blocked by the pixel driving circuit DC of the corresponding pixel area PA. Therefore, in the display device according to the embodiment of the present invention, it is possible to prevent a decrease in light extraction efficiency due to the pixel driving circuit DC of each pixel area PA.

[0069] The light emitting element 300 of each pixel area PA may be electrically connected to the second thin film transistor T2 of the pixel driving circuit DC located in the corresponding pixel area PA. For example, the second source electrode 250 of each pixel area PA may be electrically connected to the first electrode 310 of the corresponding pixel area PA. The element protective film 130 and the planarization film 140 may include an electrode contact hole that partially exposes the second source electrode 250 of each pixel area PA. For example, the first electrode 310 of each pixel area PA may directly contact the second source electrode 250 of the corresponding pixel area PA through one of the electrode contact holes. The electrode contact hole may be located outside the light emitting area EA defined in each pixel area PA. For example, the electrode contact hole may overlap the bank insulating film 150. An end of the first electrode 310 located in each pixel area PA may be covered by the bank insulating film 150. The light emitting layer 320 and the second electrode 330 of each pixel area PA may be sequentially stacked on a portion of the corresponding first electrode 310 exposed by the bank insulating film 150. The first electrodes 310 in each pixel region PA may be insulated from the first electrodes 310 in the adjacent pixel regions PA by the bank insulating film 150.

[0070] The first electrode 310, the light emitting layer 320, and the second electrode 330 of each pixel area PA may be stacked on the top surface of each flat protrusion 140p and the bottom surface of the flat groove 140g located in the corresponding pixel area PA. For example, in the display device according to the embodiment of the present invention, the light emitted from each pixel area PA may include light L1 generated by a part of the light emitting layer 320 located on the bottom surface of the flat groove 140g of the corresponding pixel area PA and light L2 generated by a part of the light emitting layer 320 located on each top surface of the flat protrusion 140p of the corresponding pixel area PA. The first electrode 310, the light emitting layer 320, and the second electrode 330 of each pixel area PA may extend on the side surface 140s of each flat protrusion 140p located in the corresponding pixel area PA. For example, the side surface 140s of each flat protrusion 140p located in each pixel area PA may directly contact the first electrode 310 of the corresponding pixel area PA. That is, in the display device according to the embodiment of the present invention, the bend formed by the flat protrusion 140p of each pixel region PA may be covered by the second electrode 330 of the corresponding pixel region PA. Thus, in the display device according to the embodiment of the present invention, the light totally reflected between the first electrode 310 and the second electrode 330 of each pixel region PA may be emitted to the outside by the second electrode 330 covering the side surface 140s of each flat protrusion 140p in the corresponding pixel region PA. Also, in the display device according to the embodiment of the present invention, the light L3 and L4 emitted in the side direction from a part of the light emitting layer 320 located on the upper surface of each flat protrusion 140p of each pixel region PA may be reflected toward the element substrate 100 by the second electrode 330 of the corresponding pixel region PA. Therefore, the light extraction efficiency may be improved in the display device according to the embodiment of the present invention.

[0071] In the display device according to the embodiment of the present invention, the light L3 and L4 emitted in the lateral direction from a portion of the light emitting layer 320 located on the upper surface of each flat protrusion 140p of each pixel region PA can be reflected in various directions. For example, in the display device according to the embodiment of the present invention, the light L3 reflected by a portion of the second electrode 330 located near the upper surface of each flat protrusion 140p can be reflected again toward the device substrate 100 by a portion of the second electrode 330 located on the upper surface of the corresponding flat protrusion 140p. In addition, in the display device according to the embodiment of the present invention, the light L4 emitted toward a portion of the second electrode 330 located far from the upper surface of each flat protrusion 140p can be reflected toward the device substrate 100 by the corresponding portion of the second electrode 330. As a result, in the display device according to the embodiment of the present invention, the light generated by each light emitting element 300 can be emitted at various angles by the second electrode 330 covering each flat protrusion 140p. Therefore, in the display device according to the embodiment of the present invention, the decrease in brightness due to an increase in the viewing angle can be mitigated.

[0072] An insulating pattern 150p may be located within the light emitting area EA of each pixel area PA. The insulating pattern 150p may be located on a side surface 140s of each flat protrusion 140p. For example, the insulating pattern 150p may be located between a portion of the first electrode 310 and a portion of the light emitting layer 320 stacked on the side surface 140s of each flat protrusion 140p. Thus, in the display device according to the embodiment of the present invention, a portion of the light emitting layer 320 located on the side surface 140s of each flat protrusion 140p may be separated from a corresponding portion of the first electrode 310 by the insulating pattern 150p. The insulating pattern 150p may include an insulating material. For example, the insulating pattern 150p may be an inorganic insulating material such as silicon oxide (SiOx) and silicon nitride (SiNx). The insulating pattern 150p may include the same material as the bank insulating film 150. Therefore, in the display device according to the embodiment of the present invention, light may not be emitted from some regions of the light-emitting layer 320 located on the side surfaces 140s of each flat protrusion 140p.

[0073] In general, the light emitting layer 320 of each pixel area PA may be formed by a deposition process with poor step coverage. For example, in the display device according to the embodiment of the present invention, a portion of the light emitting layer 320 located on the side surface 140s of each flat protrusion 140p may be formed with a relatively small thickness. The light emitting layer 320 may have a resistance proportional to its thickness. Thus, in the display device according to the embodiment of the present invention, a portion of the light emitting layer 320 formed on the side surface 140s of each flat protrusion 140p may have a relatively small resistance. An electric field may be concentrated in a portion of the light emitting layer 320 having a relatively small resistance. That is, when a portion of the light emitting layer 320 having a relatively small resistance emits light, other portions of the light emitting layer 320 having a relatively high resistance may not emit light. Therefore, in the display device according to an embodiment of the present invention, a portion of the light-emitting layer 320 formed with a relatively small thickness on the side 140s of each flat protrusion 140p does not emit light, thereby preventing a reduction in the light-emitting area due to a difference in resistance of the light-emitting layer 320.

[0074] Light emitted from the light emitting element 300 of each pixel region PA may embody the same color as light emitted from the light emitting element 300 of the adjacent pixel region PA. For example, the light emitting element 300 of each pixel region PA may emit white light. The light emitting layer 320 of each pixel region PA may include the same material as the light emitting layer 320 of the adjacent pixel region PA. The light emitting layer 320 of each pixel region PA may have the same structure as the light emitting layer 320 of the adjacent pixel region PA. For example, the light emitting layer 320 of each pixel region PA may be formed simultaneously with the light emitting layer 320 of the adjacent pixel region PA. The light emitting layer 320 of each pixel region PA may be in direct contact with the light emitting layer 320 of the adjacent pixel region PA. For example, the light emitting layer 320 of each pixel region PA may extend onto the bank insulating film 150.

[0075] Each pixel area PA may embody a different color from the adjacent pixel area PA. For example, a color filter 600 may be located between the element substrate 100 and the first electrode 310 of each pixel area PA. The color filter 600 of each pixel area PA may be located on a path of light emitted from the light emitting element 300 of the corresponding pixel area PA. For example, the color filter 600 of each pixel area PA may overlap with the light emitting area EA of the corresponding pixel area PA. The color filter 600 of each pixel area PA may be located between the element protection layer 130 and the planarization layer 140. A step due to the color filter 600 of each pixel area PA may be removed by the planarization layer 140. The color filter 600 of each pixel area PA may have a size larger than the light emitting area EA of the corresponding pixel area PA. As a result, in the display device according to the embodiment of the present invention, a light leakage phenomenon due to light that does not pass through the color filter 600 of each pixel area PA may be prevented.

[0076] The voltage applied to the second electrode 330 of each pixel area PA may be the same as the voltage applied to the second electrode 330 of the adjacent pixel area PA. For example, the second electrode 330 of each pixel area PA may be electrically connected to the second electrode 330 of the adjacent pixel area PA. The second electrode 330 of each pixel area PA may be formed simultaneously with the second electrode 330 of the adjacent pixel area PA. For example, the second electrode 330 of each pixel area PA may include the same material as the second electrode 330 of the adjacent pixel area PA. The second electrode 330 of each pixel area PA may be in direct contact with the second electrode 330 of the adjacent pixel area PA. Thus, in the display device according to an embodiment of the present invention, a process of forming the second electrode 330 in each pixel area PA can be simplified. In addition, in the display device according to the embodiment of the present invention, the brightness of light emitted from the light emitting element 300 of the corresponding pixel area PA can be adjusted according to a data signal applied to the pixel driving circuit DC of each pixel area PA.

[0077] A sealing unit 400 may be positioned on the light emitting element 300 of each pixel region PA. The sealing unit 400 can prevent damage to the light emitting element 300 due to external moisture or impact. For example, the light emitting element 300 of each pixel region PA may be completely covered by the sealing unit 400. The flat groove 140g of each pixel region PA may be filled with the sealing unit 400. The sealing unit 400 may include an insulating material. For example, the sealing unit 400 may include an olefin-based material. The sealing unit 400 may include a moisture-absorbing material.

[0078] An encapsulation substrate 500 may be disposed on the encapsulation unit 400. The encapsulation substrate 500 may be coupled to the element substrate 100 on which the light emitting element 300 is formed by the encapsulation unit 400. For example, the encapsulation unit 400 may include an adhesive material. The encapsulation substrate 500 may prevent the light emitting element 300 from being damaged by external moisture or impact. The encapsulation substrate 500 may include a material having a relatively high thermal conductivity. For example, the encapsulation substrate 500 may include metals such as aluminum (Al), iron (Fe) and nickel (Ni). Thus, in the display device according to an embodiment of the present invention, heat generated by the pixel driving circuit DC and the light emitting element 300 of each pixel area PA can be released through the encapsulation substrate 500. Thus, in the display device according to an embodiment of the present invention, deterioration of each light emitting element 300 due to heat can be prevented.

[0079] 6 to 11 are views sequentially illustrating a method of forming a display device according to an embodiment of the present invention.

[0080] A method for forming a display device according to an embodiment of the present invention will be described with reference to Figs. 4 and 6 to 11. First, as shown in Fig. 6, the method for forming a display device according to an embodiment of the present invention may include the steps of forming a light blocking pattern 105 on each pixel region PA of an element substrate 100, forming a device buffer layer 110 covering the light blocking pattern 105, forming a pixel driving circuit including the device buffer layer 110, forming an interlayer insulating film 120 on the device buffer layer 110, forming a color filter 600 on a device protection layer 130 covering the pixel driving circuit, forming a planarization layer 140 covering the color filter 600, and forming a first mask pattern MR1 on the planarization layer 140.

[0081] The pixel driving circuit may be formed outside the light emitting area EA defined in each pixel area PA by a subsequent process. The color filter 600 may be formed to overlap the light emitting area EA of each pixel area PA. The planarization film 140 may be formed of a negative material. For example, the first mask pattern MR1 may overlap an area in which the flat protrusion 140p will be formed by a subsequent process. The flat protrusion 140p may be formed within the light emitting area EA of each pixel area PA. For example, the first mask pattern MR1 may be formed to overlap the color filter 600 of each pixel area PA.

[0082] As shown in FIG. 7, a method of forming a display device according to an embodiment of the present invention may include forming a planar protrusion 140p on a planarization layer 140 using a first mask pattern MR1.

[0083] The step of forming the flat protrusions 140p may include etching a portion of the planarization layer 140 exposed by the first mask pattern MR1. For example, a flat groove 140g may be formed on the outer side of each flat protrusion 140p. The step of forming the flat protrusions 140p may include a dry-etch process. Thus, in the method of forming a display device according to an embodiment of the present invention, a side surface 140s of each flat protrusion 140p may be formed in a concave shape toward the inner side of the corresponding flat protrusion 140p.

[0084] As shown in FIG. 8, a method for forming a display device according to an embodiment of the present invention may include the steps of removing a first mask pattern MR1, forming electrode contact holes in a planarization film 140 to partially expose a pixel driving circuit of each pixel area PA, and forming a first electrode 310 electrically connected to a corresponding pixel driving circuit through one of the electrode contact holes on the planarization film 140 of each pixel area PA.

[0085] The first electrode 310 of each pixel area PA may extend along the surfaces of each flat protrusion 140p and flat groove 140g located on the corresponding pixel area PA. For example, the side surface 140s and the top surface of each flat protrusion 140p located on each pixel area PA and the bottom surface of the flat groove 140g may be covered by the first electrode 310 of the corresponding pixel area PA.

[0086] As shown in FIG. 9, a method for forming a display device according to an embodiment of the present invention may include a step of forming a bank insulating film 150 covering a first electrode 310 of each pixel area PA, and a step of forming a photoresist pattern (PR) having openings overlapping with the light emitting areas EA of each pixel area PA on the bank insulating film 150.

[0087] The bank insulating film 150 may be formed of an inorganic insulating material such as silicon oxide (SiOx) and silicon nitride (SiNx). The bank insulating film 150 may be formed of a liner film (linear layer). For example, the bank insulating film 150 located on each pixel region PA may have a uniform thickness. The bank insulating film 150 may extend parallel to the first electrode 310 of the corresponding pixel region PA along the surfaces of each flat protrusion 140p and flat groove 140g located on each pixel region PA. As shown in FIG. 10, a method of forming a display device according to an embodiment of the present invention may include patterning a bank insulating layer 150 using a photoresist pattern PR.

[0088] The step of patterning the bank insulating film 150 may include a step of removing a portion of the bank insulating film 150 that overlaps with the light emitting area EA of each pixel area PA. For example, a portion of the bank insulating film 150 located on the top surface of each flat protrusion 140p and the bottom surface of the flat groove 140g located on each pixel area PA may be removed by a patterning process using a photoresist pattern PR.

[0089] The step of patterning the bank insulating film 150 may include a dry etching process. Thus, in the method of forming a display device according to an embodiment of the present invention, a portion of the bank insulating film 150 covering the concave side surface 140s of each flat protrusion 140p may not be removed by the patterning process using the photoresist pattern PR. For example, an insulating pattern 150p may be formed on the concave side surface 140s of each flat protrusion 140p by the patterning process using the photoresist pattern PR. The insulating pattern 150p formed on the concave side surface 140s of each flat protrusion 140p may have a smaller thickness than the bank insulating film 150 located outside the light emitting area EA defined in each pixel area PA.

[0090] As shown in FIG. 11, a method of forming a display device according to an embodiment of the present invention may include forming a light emitting layer 320 on each pixel area PA of a device substrate 100 on which an insulating pattern 150p is formed.

[0091] The step of forming the light emitting layer 320 may include a deposition process. Thus, in the method of forming a display device according to an embodiment of the present invention, a portion of the light emitting layer 320 formed on the side surface 140s of each flat protrusion 140p may have a smaller thickness than the other portion of the light emitting layer 320. For example, a portion of the light emitting layer 320 formed on the insulating pattern 150p may have a smaller thickness than the other portion of the light emitting layer 320 formed on the bank insulating film 150. A portion of the light emitting layer 320 formed on the side surface 140s of each flat protrusion 140p may be separated from the corresponding first electrode 310 by the insulating pattern 150p. That is, in the method of forming a display device according to an embodiment of the present invention, a portion of the light emitting layer 320 formed with a relatively small thickness may be insulated from the corresponding first electrode 310 by the insulating pattern 150p.

[0092] As shown in FIG. 4, a method for forming a display device according to an embodiment of the present invention may include forming a second electrode 330 on an emission layer 320 of each pixel area PA, and attaching an encapsulation substrate 500 to the element substrate 100 on which the second electrode 330 is formed using a encapsulation unit 400.

[0093] The second electrode 330 formed on each pixel region PA may extend along the light emitting layer 320 of the corresponding pixel region PA. For example, the second electrode 330 of each pixel region PA may extend along the top surface and side surface 140s of each flat protrusion 140p located on the corresponding pixel region PA. The light emitting layer 320 may be located between the insulating pattern 150p and the second electrode 330 on the side surface 140s of each flat protrusion 140p. As a result, in the method of forming the display device according to the embodiment of the present invention, an electric field may not be concentrated in a portion of the light emitting layer 320 located on the side surface 140s of each flat protrusion 140p. Therefore, in the method of forming the display device according to the embodiment of the present invention, a portion of the light emitting layer 320 located on the side surface 140s of each flat protrusion 140p may not emit light. That is, in the method of forming the display device according to the embodiment of the present invention, light may be emitted only from a portion of the light emitting layer 320 located on the top surface of each flat protrusion 140p and the bottom surface of the flat groove 140g.

[0094] As a result, in the display device according to the embodiment of the present invention, the planarization film 140 of each pixel region PA includes the flat protrusion 140p overlapping the light emitting region EA of the corresponding pixel region PA, and a portion of the first electrode 310 and a portion of the light emitting layer 320 located on the side surface 140s of each flat protrusion 140p may be separated from each other by the insulating pattern 150p. As a result, in the display device according to the embodiment of the present invention, a reduction in the light emitting area due to a portion of the light emitting layer 320 formed with a relatively small thickness on the side surface 140s of each flat protrusion 140p is prevented, and light totally reflected between the first electrode 310 and the second electrode 330 of each light emitting element 300 due to bending by each flat protrusion 140p may be emitted to the outside. Therefore, in the display device according to the embodiment of the present invention, the light extraction efficiency can be improved without reducing the light emitting efficiency.

[0095] In addition, in the display device according to the embodiment of the present invention, light generated by the light emitting element 300 of each pixel area PA may be emitted at various angles by the second electrode 330 of the corresponding pixel area PA covering the flat protrusion 140p. Therefore, in the display device according to the embodiment of the present invention, a decrease in brightness due to an increase in the viewing angle may be mitigated.

[0096] In addition, in the display device according to the embodiment of the present invention, the side surface 140s of each flat protrusion 140p may have a concave shape toward the inside of the corresponding flat protrusion 140p. Thus, in the display device according to the embodiment of the present invention, the insulating pattern 150p located on the side surface 140s of each flat protrusion 140p may be formed by a process of forming a bank insulating film 150 that covers the edge of the first electrode 310 located on each pixel region PA. Therefore, in the display device according to the embodiment of the present invention, it is possible to effectively improve the light extraction efficiency without reducing the process efficiency.

[0097] In the display device according to the embodiment of the present invention, the pixel driving circuit DC of each pixel area PA is described as being composed of a first thin film transistor T1, a second thin film transistor T2, a third thin film transistor T3, and a storage capacitor Cst. However, in the display device according to the other embodiment of the present invention, the pixel driving circuit DC of each pixel area PA may include at least one thin film transistor. For example, in the display device according to the other embodiment of the present invention, the pixel driving circuit DC of each pixel area PA may include only the first thin film transistor T1, the second thin film transistor T2, and a storage capacitor Cst. In addition, in the display device according to the other embodiment of the present invention, the pixel driving circuit DC of each pixel area PA may include four or more thin film transistors. As a result, in the display device according to the other embodiment of the present invention, the degree of freedom in the configuration of the pixel driving circuit DC located in each pixel area PA can be improved.

[0098] In the display device according to the embodiment of the present invention, the position and electrical connection of the second drain electrode 240 and the second source electrode 250 located in each pixel area PA may vary depending on the configuration of the pixel driving circuit DC located in the corresponding pixel area PA and / or the type of the corresponding thin film transistors T1, T2, T3. For example, in the display device according to the other embodiment of the present invention, the second gate electrode 230 of the second thin film transistor T2 located in each pixel area PA may be electrically connected to the first drain electrode of the first thin film transistor T1 located in the corresponding pixel area PA, and the first electrode 310 of each pixel area PA may be electrically connected to the second drain electrode 240 of the corresponding pixel area PA. Therefore, in the display device according to the other embodiment of the present invention, the degree of freedom in the configuration of the pixel driving circuit DC located in each pixel area PA and the type of the thin film transistors T1, T2, T3 included in each pixel driving circuit DC can be improved.

[0099] In the display device according to the embodiment of the present invention, the planar shape of each flat protrusion 140p is described as a hexagon. However, in the display device according to the other embodiment of the present invention, each flat protrusion 140p may have various planar shapes. For example, as shown in FIG. 12a, in the display device according to the other embodiment of the present invention, the planar shape of each flat protrusion 140p in each light-emitting area EA may be a bar shape extending in one direction, and the flat groove 140g located on each light-emitting area EA may have a shape extending parallel to the corresponding flat protrusion 140p. As a result, in the display device according to the other embodiment of the present invention, the process of forming the flat protrusion 140p and the flat groove 140g in the light-emitting area EA of each pixel area PA can be simplified. Therefore, in the display device according to the embodiment of the present invention, the process efficiency and light extraction efficiency can be improved, and the decrease in brightness due to an increase in the viewing angle can be reduced.

[0100] In the display device according to another embodiment of the present invention, the planar shape of each flat protrusion 140p may be a polygon. For example, as shown in Fig. 12b, in the display device according to another embodiment of the present invention, the planar shape of each flat protrusion 140p may be a triangle. Also, as shown in Fig. 12c, in the display device according to another embodiment of the present invention, the planar shape of each flat protrusion 140p may be a rectangle. This allows for greater freedom in the planar shape of each flat protrusion 140p in the display device according to another embodiment of the present invention.

[0101] As shown in Fig. 12d, in the display device according to another embodiment of the present invention, the planar shape of each flat protrusion 140p may be circular. As a result, in the display device according to another embodiment of the present invention, the light reflected by the second electrode covering each flat protrusion 140p may have a uniform brightness regardless of the azimuth angle. Therefore, in the display device according to another embodiment of the present invention, the brightness deviation due to the azimuth angle and the viewing angle can be prevented.

[0102] In the display device according to the embodiment of the present invention, the flat grooves 140g are described as being located only between the flat protrusions 140p. However, as shown in Fig. 12e, in the display device according to the other embodiment of the present invention, the flat grooves 140g may extend along the edge of each flat protrusion 140p. For example, in the display device according to the other embodiment of the present invention, the planar shape of each flat protrusion 140p may be defined by the flat groove 140g. This allows for increased freedom in the relative positions of each flat protrusion 140p and the flat groove 140g in the display device according to the other embodiment of the present invention.

[0103] In the display device according to the embodiment of the present invention, a plurality of flat protrusions 140p are positioned within the light emitting area EA of each pixel area PA. However, in the display device according to another embodiment of the present invention, one flat protrusion 140p and a flat groove 140g surrounding the flat protrusion 140p may be positioned within the light emitting area EA of each pixel area PA. As a result, in the display device according to the other embodiment of the present invention, the degree of freedom regarding the number of flat protrusions 140p and the number of flat grooves 140g positioned within the light emitting area EA of each pixel area PA can be improved.

[0104] In the display device according to the embodiment of the present invention, each flat protrusion 140p is described as having a size larger than the flat grooves 140g located between the flat protrusions 140p. However, as shown in Fig. 13, in the display device according to another embodiment of the present invention, a part of the planarization film 140 overlapping with the light emitting area EA of each pixel area PA may include a plurality of flat grooves 140g and the flat protrusions 140p located between the flat grooves 140g, and the flat protrusions 140p may have a width smaller than each flat groove 140g. As a result, in the display device according to the other embodiment of the present invention, the degree of freedom regarding the relative sizes of the flat protrusions 140p and the flat grooves 140g located on the light emitting area EA of each pixel area PA may be improved.

[0105] In a display device according to another embodiment of the present invention, light generated by the light emitting layer 320 of each light emitting element 300 may be emitted to the outside through the second electrode 330 of the corresponding light emitting element 300. For example, in a display device according to another embodiment of the present invention, the first electrode 310 of each light emitting element 300 may include metals such as aluminum (Al) and silver (Ag). The first electrode 310 may have a multi-layer structure. For example, the first electrode 310 may have a structure in which a reflective electrode made of a metal is located between transparent electrodes made of transparent conductive materials such as ITO and IZO. The second electrode 330 of each light emitting element 300 may have a higher transmittance than the first electrode 310 of the corresponding light emitting element 300. For example, the second electrode 330 of each light emitting element 300 may be a transparent electrode made of transparent conductive materials such as ITO and IZO, or a semi-transparent electrode in which metals such as Ag and Mg are thinly formed. As a result, in the display device according to another embodiment of the present invention, as shown in FIG. 14, a portion of the light emitting layer 320 located at the bottom of each flat groove 140g may generate light L5 emitted in a direction perpendicular to the upper surface of the device substrate 100 and light L6, L7 emitted obliquely to the upper surface of the device substrate 100. The light L6, L7 emitted obliquely to the upper surface of the device substrate 100 from a portion of the light emitting layer 320 located at the bottom of each flat groove 140g may be reflected to the outside by the first electrode 310 covering the side surface 140s of the corresponding flat groove 140g. The light L6, L7 reflected by the first electrode 310 covering the side surface 140s of each flat groove 140g may be reflected at various angles depending on the position of incidence. Therefore, in the display device according to another embodiment of the present invention, the light extraction efficiency is improved and a decrease in brightness due to an increase in the viewing angle may be mitigated. The light L8 generated in a portion of the light emitting layer 320 located at the upper surface of the flat protrusion 140p may be emitted to the outside without being reflected by the first electrode 310.

[0106] 15 to 19 are diagrams sequentially illustrating a method of forming a display device according to another embodiment of the present invention.

[0107] A method of forming a display device according to another embodiment of the present invention will be described with reference to Figures 13 and 15 to 19. First, as shown in Figure 15, the method of forming a display device according to another embodiment of the present invention may include forming an element protection layer 130 and a planarization layer 140 on an element substrate 100 on which pixel driving circuits of each pixel area PA are formed, and forming a plurality of planarization grooves in a portion of the planarization layer 140 overlapping with an emission area EA of each pixel area PA using a second mask pattern MR2.

[0108] The step of forming the plurality of flat grooves 140g may include etching a portion of the planarization film 140 exposed by the second mask pattern MR2. For example, a flat protrusion 140p may be formed between the flat grooves 140g. The step of forming the plurality of flat grooves 140g may include a dry etching process. Thus, in the method of forming a display device according to another embodiment of the present invention, a side surface 140s of each flat groove 140g may be formed to be convex toward an outer side of the corresponding flat groove 140g.

[0109] As shown in FIG. 16, a method of forming a display device according to another embodiment of the present invention may include the steps of removing the second mask pattern MR2, forming electrode contact holes in the planarization film 140 to partially expose the pixel driving circuit of each pixel area PA, and forming a first electrode 310 electrically connected to a corresponding pixel driving circuit through one of the electrode contact holes on the planarization film 140 of each pixel area PA.

[0110] The first electrode 310 of each pixel area PA may extend along the surface of each flat groove 140g and flat protrusion 140p located on the corresponding pixel area PA. For example, the side surface 140s and the bottom surface of each flat groove 140g located on each pixel area PA and the top surface of the flat protrusion 140p may be covered by the first electrode 310 of the corresponding pixel area PA.

[0111] As shown in FIG. 17, a method of forming a display device according to another embodiment of the present invention may include forming a bank insulating layer 150 covering a first electrode 310 of each pixel area PA.

[0112] The bank insulating film 150 may be formed of an inorganic insulating material such as silicon oxide (SiOx) and silicon nitride (SiNx). The bank insulating film 150 may be formed of a liner film (linear layer). For example, the bank insulating film 150 located on each pixel region PA may have a uniform thickness. The bank insulating film 150 may extend parallel to the first electrode 310 of the corresponding pixel region PA along the surfaces of each planar groove 140g and planar protrusion 140p located on each pixel region PA. As shown in FIG. 18, a method of forming a display device according to another embodiment of the present invention may include patterning a bank insulating film 150 to partially expose a first electrode 310 in each pixel area PA.

[0113] A portion of the first electrode 310 located within each pixel region PA exposed by the bank insulating film 150 may overlap with the light emitting region EA of the corresponding pixel region PA. For example, the process of patterning the bank insulating film 150 may include a process of defining the light emitting region EA within each pixel region PA. The process of patterning the bank insulating film 150 may include a dry etching process. Therefore, in the method of forming the display device according to an embodiment of the present invention, a portion of the bank insulating film 150 covering the convex side surface 140s of each flat groove 140g may not be completely removed. For example, an insulating pattern 150p may be formed on the convex side surface 140s of each flat groove 140g. The insulating pattern 150p formed on the convex side surface 140s of each flat groove 140g may have a smaller thickness than the bank insulating film 150 defining the light emitting region EA of each pixel region PA.

[0114] As shown in FIG. 19, a method for forming a display device according to another embodiment of the present invention may include a step of forming an emission layer 320 on each pixel area PA of an element substrate 100 on which an insulating pattern 150p is formed, and a step of forming a second electrode 330 on the emission layer 320 of each pixel area PA.

[0115] The process of forming the light-emitting layer 320 may include a deposition process. For example, a portion of the light-emitting layer 320 formed on the side 140s of each flat groove 140g may have a relatively small thickness. The second electrode 330 formed on each pixel region PA may extend along the light-emitting layer 320 of the corresponding pixel region PA. For example, a portion of the first electrode 310, an insulating pattern 150p, a portion of the light-emitting layer 320, and a portion of the second electrode 330 may be stacked in sequence on the side 140s of each flat groove 140g. That is, in the method of forming a display device according to another embodiment of the present invention, a portion of the light-emitting layer 320 formed on the side 140s of each flat groove 140g may be insulated from the corresponding first electrode 310 by the insulating pattern 150p. Therefore, in the method of forming a display device according to another embodiment of the present invention, light may not be emitted from a portion of the light-emitting layer 320 located on the side 140s of each flat groove 140g.

[0116] As shown in FIG. 13, the display device according to another embodiment of the present invention may include a step of forming a sealing unit 400 on the second electrode 330 of each pixel area PA.

[0117] The encapsulation unit 400 may be formed in a multi-layer structure. For example, the encapsulation unit 400 may include a first encapsulation layer 410, a second encapsulation layer 420, and a third encapsulation layer 430 sequentially stacked on the second electrode 330 of each pixel region PA. The first encapsulation layer 410, the second encapsulation layer 420, and the third encapsulation layer 430 may include an insulating material. The second encapsulation layer 420 may include a material different from the first encapsulation layer 410 and the third encapsulation layer 430. The encapsulation unit 400 may be formed in a laminated structure of an inorganic insulating film and an organic insulating film. For example, the first encapsulation layer 410 and the third encapsulation layer 430 may be inorganic insulating films made of silicon nitride (SiNx) or silicon oxide (SiOx), and the second encapsulation layer 420 may be an organic insulating film made of an organic insulating material. As a result, in the method of forming a display device according to another embodiment of the present invention, damage to the light emitting element 300 due to external moisture or impact can be effectively prevented, and light extraction efficiency can be improved. In addition, in the method for forming a display device according to another embodiment of the present invention, it is possible to effectively reduce the decrease in luminance caused by an increase in the viewing angle without reducing process efficiency and light emission efficiency.

[0118] In the display device according to an embodiment of the present invention, the width of the flat groove 140g located between the adjacent flat protrusions 140p is described as being smaller than the width of each flat protrusion 140p. However, as shown in FIG. 20 and FIG. 21, in the display device according to another embodiment of the present invention, the distance d between the adjacent flat protrusions 140p may be equal to the width w of each flat protrusion 140p. That is, in the display device according to another embodiment of the present invention, the flat groove 140g may have the same width as each flat protrusion 140p. As a result, in the display device according to the other embodiment of the present invention, the light extraction efficiency can be effectively improved without reducing the light emission efficiency. Therefore, in the display device according to the technical idea of ​​the present invention, the power required for the operation of each pixel region PA can be effectively reduced. In addition, in the display device according to the other embodiment of the present invention, the decrease in luminance due to an increase in the viewing angle can be effectively alleviated. [Explanation of symbols]

[0119] 100 Element substrate 140 Planarization film 140g flat groove 140s flat side 140p flat protrusion 150 Bank insulating film 150p insulation pattern 300 Light emitting element 400 Sealing Unit

Claims

1. A bank insulating film that is located on the element substrate and defines a light-emitting region within a pixel region; a planarization film located between the element substrate and the bank insulating film, the planarization film including a flat protrusion overlapping the light emitting region; an insulating pattern located on a side surface of the flat protrusion and spaced apart from a top surface of the flat protrusion; and a light emitting element located on the planarization film of the light emitting region and having a stacked structure of a first electrode, a light emitting layer, and a second electrode; The side surface of the flat protrusion has a shape recessed toward the inside of the flat protrusion, The insulating pattern is located between the first electrode and the light-emitting layer of the light-emitting element.

2. The display device of claim 1 , wherein the planar shape of the flat protrusion is a polygon.

3. The display device of claim 1 , wherein the insulating pattern comprises the same material as the bank insulating film.

4. The bank insulating film is a liner layer having a certain thickness, The display device of claim 3 , wherein the thickness of the insulating pattern is less than the thickness of the bank insulating film.

5. 10. The display device of claim 1, wherein the second electrode has a greater reflectivity than the first electrode.

6. The display device of claim 5 , further comprising a color filter located between the element substrate and the planarization film and overlapping the light-emitting region.

7. The display device of claim 1 , wherein the planarization film further comprises a planar groove surrounding the planar protrusion.

8. The display device of claim 7 , wherein a width of the planar groove is smaller than a width of the planar protrusion.

9. a planarization film overlying the device substrate, the planarization film including a planarization groove; a first electrode located on the planarization film and covering a side surface and a bottom surface of the planarized groove; an insulating pattern located on a partial region of the first electrode covering a side surface of the flat groove; a bank insulating film located on the planarization film and covering an edge of the first electrode; a light emitting layer located on a portion of the first electrode exposed by the bank insulating film; and a second electrode located on the light emitting layer and extending onto the bank insulating film; The bank insulating film is located outside the flat groove.

10. The display device according to claim 9 , wherein the side surface of the flat groove has a convex shape toward an outside of the flat groove.

11. The display device of claim 9 , wherein the insulating pattern is spaced apart from the bottom surface of the flat groove.

12. The display device according to claim 9 , wherein the planar shape of the flat groove is polygonal.

13. The display device of claim 9 , wherein the second electrode has a transmittance greater than the first electrode.

14. a sealing unit located on the second electrode, The display device according to claim 13 , wherein the sealing unit has a laminated structure of an inorganic insulating film made of an inorganic insulating material and an organic insulating film made of an organic insulating material.

15. the planarization film further includes a planar protrusion overlapping the light emitting region; 14. The display device of claim 13, wherein a width of the planar protrusion is less than a width of the planar groove.

16. The display device of claim 9 , wherein the insulating pattern is disposed between the first electrode and the light-emitting layer.

17. The display device of claim 9 , wherein the insulating pattern comprises the same material as the bank insulating film.

18. The bank insulating film is a liner layer having a certain thickness, The display device of claim 17, wherein the thickness of the insulating pattern is less than the thickness of the bank insulating film.

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