Display Devices

Abstract

A display device includes a substrate; a plurality of pixels located on the substrate; a first electrode arranged on the substrate for each of the plurality of pixels; a pixel defining layer located on the substrate along a boundary of each pixel and including an opening exposing the first electrode of each pixel; an organic layer located on the first electrode in the opening of the pixel defining layer; and a second electrode located on the organic layer, the pixel defining layer including a first pixel defining layer and a second pixel defining layer stacked on a surface of the first pixel defining layer, the surface of the first pixel defining layer including an upper surface and a side surface, and the surface roughness of the upper surface of the first pixel defining layer is greater than the surface roughness of the first electrode.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2019-0013976, filed on February 1, 2019, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0003] Aspects of embodiments of the present disclosure relate to a display device and a method of manufacturing the same. Background Art

[0004] With the development of multimedia, display devices have gradually become important. In response to this, various display devices have been developed, such as liquid crystal display devices and organic light emitting display devices, etc.

[0005] For example, an organic light emitting display device includes an organic light emitting element including two electrodes and an organic light emitting layer interposed between the two electrodes to emit light. Since the organic light emitting display device includes an organic light emitting element controlled for each pixel, it can be implemented as a thin and lightweight display device with low power consumption, and has characteristics such as a wide viewing angle, high brightness and high contrast, and a fast response speed. Therefore, it has attracted attention as a next-generation display device.

[0006] An organic light emitting display device includes a plurality of pixels and may further include a pixel defining layer for defining the boundaries of each pixel. The pixel defining layer may be formed by laminating two or more layers of different types. If the bonding force between the different types of layers is weak, the layers may be peeled off during processing. The components of the peeled layers may adversely affect the formation of the organic layer, which may reduce the display quality and reliability of the entire display device. Summary of the invention

[0007] According to an aspect of an embodiment of the present disclosure, there is provided a display device having improved adhesion between a first pixel defining layer and a second pixel defining layer.

[0008] According to another aspect of an embodiment of the present disclosure, there is provided a method of manufacturing a display device capable of improving adhesion between a first pixel defining layer and a second pixel defining layer.

[0009] However, aspects of the present disclosure are not limited to those described herein. The above and other aspects of the present disclosure will become more apparent to those skilled in the art to which the present disclosure belongs by referring to the further detailed description of the present disclosure described below.

[0010] According to one or more embodiments of the present disclosure, a display device includes: a substrate; a plurality of pixels located on the substrate; a first electrode arranged on the substrate for each of the plurality of pixels; a pixel defining layer located on the substrate along a boundary of each pixel and including an opening exposing the first electrode of each pixel; an organic layer located on the first electrode in the opening of the pixel defining layer; and a second electrode located on the organic layer, wherein the pixel defining layer includes a first pixel defining layer and a second pixel defining layer stacked on a surface of the first pixel defining layer, wherein the surface of the first pixel defining layer includes an upper surface and a side surface, and wherein a surface roughness of the upper surface of the first pixel defining layer is greater than a surface roughness of the first electrode.

[0011] According to aspects of the embodiments of the present disclosure, the adhesion between the first pixel defining layer and the second pixel defining layer is improved, and the display quality and reliability of the display device are improved.

[0012] The aspects and effects of the present invention are not limited to the aspects and effects described above, and other aspects and effects not described herein will become apparent to those skilled in the art from the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The above and other aspects and features of the present disclosure will become more apparent by describing in more detail some example embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0014] Figure 1 is a plan view schematically showing a display device according to an embodiment;

[0015] Figure 2 is along Figure 1 A cross-sectional view taken along line II-II';

[0016] Figure 3 yes Figure 2 an enlarged cross-sectional view of area "A";

[0017] Figure 4A is a graph showing the brightness of a display device according to a comparative example;

[0018] Figure 4B is a diagram showing brightness of a display device according to an embodiment;

[0019] Figure 5 is a cross-sectional view of a display device according to another embodiment;

[0020] Figure 6 is a cross-sectional view of a display device according to another embodiment;

[0021] Figure 7 is a cross-sectional view of a display device according to another embodiment;

[0022] Figure 8 is a cross-sectional view of a display device according to another embodiment;

[0023] Fig. 9 is a cross-sectional view of a display device according to another embodiment;

[0024] FIG. 10A to FIG. 10D is a plan view of a display device according to various embodiments;

[0025] Figures 11 to 17 is a cross-sectional view illustrating tasks of a method of manufacturing a display device according to an embodiment; and

[0026] Fig.18 and Fig.19 is a cross-sectional view illustrating tasks of a method of manufacturing a display device according to another embodiment. DETAILED DESCRIPTION

[0027] By referring to the following detailed description of some example embodiments and the accompanying drawings, the features of the inventive concept and its implementation method can be more easily understood. However, the inventive concept can be embodied in a variety of different forms and should not be understood as being limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make this disclosure comprehensive and complete, and to fully convey the concept of the inventive concept to those skilled in the art, and the inventive concept will be defined by the appended claims. The same reference numerals refer to the same elements throughout the specification.

[0028] It will be understood that when an element or layer is referred to as being "located on" or "connected to" or "coupled to" another element or layer, the element or layer may be directly located on or directly connected to or coupled to the other element, or one or more intervening elements or layers may be present. Conversely, when an element is referred to as being "directly located on" or "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers. As used herein, the term "and / or" includes any and all combinations of one or more of the listed associated items.

[0029] For ease of description, spatially relative terms such as "below", "below", "down", "above", and "on" may be used herein to describe the relationship between an element or feature and another element or feature (or other elements or features) as shown in the figure. It is understood that spatially relative terms are intended to include different orientations of devices in use or operation in addition to the orientations depicted in the figure. For example, if the device in the figure is turned over, the elements described as being "below" or "below" other elements or features will then be oriented to be located "above" other elements or features. Therefore, the example term "below" can include both above and below orientations. For example, the device can be oriented in other ways (e.g., rotated 90 degrees or in other orientations), and the spatially relative descriptive language used herein can be interpreted accordingly.

[0030] It is understood that although the terms "first", "second", etc. may be used herein to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited to these terms. These terms are used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, the "first" element, component, region, layer or part discussed below may be referred to as a "second" element, component, region, layer or part without exceeding the teachings of the present inventive concept.

[0031] The meaning of “include” or “comprising” may specify attributes, fixed numbers, steps, operations, elements, parts or a combination thereof, but does not exclude other attributes, fixed numbers, steps, operations, elements, parts or a combination thereof.

[0032] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art to which the exemplary embodiments of the present invention are conceived. It is further understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and should not be interpreted in an idealized or overly formal sense, unless such a definition is explicitly made herein.

[0033] Some example embodiments of the present disclosure will be described herein with reference to the accompanying drawings.

[0034] Figure 1 2 is a plan view schematically showing a display device according to an embodiment. Figure 1 , in a plan view, the display device 1 according to the embodiment may include a plurality of pixels 70 disposed on a substrate 10 .

[0035] Although Figure 1It is shown that each pixel 70 has a rectangular shape, but the shape of the pixel 70 is not limited thereto and may be a circular shape, an elliptical shape, or a polygonal shape.

[0036] In an embodiment, the pixel 70 may include a first pixel 70a, a second pixel 70b, and a third pixel 70c. In an embodiment, the first pixel 70a, the second pixel 70b, and the third pixel 70c may have the same shape, but the present disclosure is not limited thereto. For example, at least one of the first pixel 70a, the second pixel 70b, and the third pixel 70c may have a shape different from the remaining pixels, and the first pixel 70a, the second pixel 70b, and the third pixel 70c may have different shapes.

[0037] The first pixel 70a, the second pixel 70b and the third pixel 70c may display different colors. For example, the first pixel 70a may be a red pixel for displaying red, the second pixel 70b may be a green pixel for displaying green, and the third pixel 70c may be a blue pixel for displaying blue.

[0038] The pixels 70 may be arranged in a matrix form. A plurality of pixels 70 may be arranged so that the display color has a stripe pattern. For example, a plurality of first pixels 70a may be arranged continuously in a first pixel column, a plurality of second pixels 70b may be arranged continuously in a second pixel column, and a plurality of third pixels 70c may be arranged continuously in a third pixel column. This arrangement rule may be repeated along the row direction. However, the arrangement of the pixels 70 is not limited to the arrangement described above. For example, the pixels 70 have the same arrangement, and the pixels 70 showing different colors may be alternately arranged along the column direction. As another example, a plurality of pixels 70 may be arranged in a honeycomb pattern.

[0039] The pixel defining layer 30 is disposed at the boundary of each pixel 70. The pixel defining layer 30 may be disposed along the column boundary and / or the row boundary of the pixel 70. The overall planar shape of the pixel defining layer 30 may be a lattice shape.

[0040] The pixel defining layer 30 includes an opening that exposes a portion of each pixel 70. A light emitting region may be disposed in the opening of the pixel defining layer 30. The light emitting region is a region where light is emitted from the organic light emitting element, which may overlap with the opening of the pixel defining layer 30. The region where the pixel defining layer 30 is located may be a non-emitting region that does not emit light.

[0041] The organic layer 40 may be disposed in the opening of the pixel defining layer 30. The organic layer 40a of the first pixel 70a, the organic layer 40b of the second pixel 70b, and the organic layer 40c of the third pixel 70c may emit light of the color of the corresponding pixel. However, the present disclosure is not limited thereto, and in an embodiment, all of the organic layers 40a, 40b, and 40c may emit light of the same color, and a wavelength conversion member or a color filter may be disposed on the light emitting path to display different colors for each pixel 70.

[0042] The pixel defining layer 30 may include a first pixel defining layer 31 and a second pixel defining layer 32. The second pixel defining layer 32 is disposed on the first pixel defining layer 31. The width of the second pixel defining layer 32 may be less than the width of the first pixel defining layer 31. In an embodiment, the second pixel defining layer 32 may completely overlap an inner portion of the first pixel defining layer 31 in a plan view. The second pixel defining layer 32 may expose a portion of the first pixel defining layer 31.

[0043] Although it is shown in the drawings that both the first pixel defining layer 31 and the second pixel defining layer 32 are arranged along pixel row boundaries and pixel column boundaries, various other modifications are possible.

[0044] In an embodiment, the second pixel defining layer 32 may be used to distinguish the arrangement of the organic layer for each pixel 70. For example, when the arrangement of the pixels 70 adopts a stripe-type method in which pixels of the same color are arranged along the column direction, since different organic layers are arranged for each pixel column, the second pixel defining layer 32 is arranged at the pixel column boundary to distinguish the organic layer. In an embodiment, regarding the pixel row boundary, since the adjacent pixels 70 in the column direction display the same color, the same material is applied to the organic layer, and it is not necessary to distinguish the organic layer for each row of the pixel 70. Therefore, at the pixel row boundary, the arrangement of the second pixel defining layer 32 may be omitted. That is, the second pixel defining layer 32 may have a shape of multiple stripes as a whole instead of a lattice shape. In an embodiment, even when the second pixel defining layer 32 is arranged in a stripe pattern, the first pixel defining layer 31 may still be arranged in a lattice shape. In this case, the organic layer or the second electrode may be directly disposed on the first pixel defining layer 31 on the pixel row boundary without the second pixel defining layer 32. In another embodiment, the first pixel defining layer 31 may also be provided in a stripe pattern by being omitted at the pixel row boundary in the same manner as the second pixel defining layer 32 .

[0045] Herein, the cross-sectional structure of the above-mentioned display device 1 will be described in more detail.

[0046] Figure 2 is along Figure 1 A cross-sectional view taken along line II-II'. Figure 3 yes Figure 2 An enlarged cross-sectional view of area "A" of FIG.

[0047] refer to Figures 1 to 3 According to the embodiment, the display device 1 may include a substrate 10, a buffer layer 11 disposed on the substrate 10, a plurality of thin film transistors located on the buffer layer 11, a through layer VIA located on the thin film transistors, a first electrode 20 located on the through layer VIA, a pixel defining layer 30 located on the through layer VIA to expose at least a portion of the first electrode 20, an organic layer 40 located on the first electrode 20, and a second electrode 50 located on the organic layer 40.

[0048] The substrate 10 may include an insulating substrate. The substrate 10 may include any one of glass, quartz, plastic, and metal foil, etc. The substrate 10 may be a rigid substrate or a flexible substrate that can be bent, folded, or rolled.

[0049] The buffer layer 11 may be disposed on the substrate 10. The buffer layer 11 serves to smooth the surface of the substrate 10 and prevent or substantially prevent penetration of moisture or external air.

[0050] A plurality of thin film transistors may be arranged for each pixel on the buffer layer 11. The thin film transistor may include a semiconductor layer CH, a gate electrode GE, a source electrode SE, and a drain electrode DE.

[0051] The semiconductor layer CH may be disposed on the buffer layer 11 , and the gate insulating film IL1 may be disposed on the semiconductor layer CH.

[0052] The gate electrode GE may be disposed on the gate insulating film IL1. The gate electrode GE may be formed of a conductive metal material. For example, the gate electrode GE may include any one of molybdenum (Mo), aluminum (Al), copper (Cu), and titanium (Ti). The gate electrode GE may be a single film or a multi-layer film.

[0053] The interlayer insulating film IL2 is provided on the gate electrode GE. The interlayer insulating film IL2 may be an inorganic film.

[0054] The source electrode SE and the drain electrode DE are provided on the interlayer insulating film IL2. The source electrode SE and the drain electrode DE are formed of a conductive metal material.

[0055] The through layer VIA is disposed on the source electrode SE, the drain electrode DE and the interlayer insulating film IL2. Here, the through layer VIA is disposed to cover the thin film transistor. The through layer VIA may be a planarization film. The through layer VIA may include an organic material, such as acrylic or polyimide. In some embodiments, the SiO x or SiN xA passivation film (not shown) made of MgO or the like may be further provided between the through layer VIA and the thin film transistor.

[0056] A plurality of first electrodes 20 are disposed on the through-layer VIA. The first electrode 20 may be electrically connected to the drain electrode DE (or the source electrode SE) of the thin film transistor through a through hole penetrating the through-layer VIA.

[0057] The first electrode 20 may be a pixel electrode provided for each pixel 70. The first electrode 20 may be an anode electrode or a cathode electrode. When the first electrode 20 is an anode electrode, the second electrode 50 becomes a cathode electrode, and such an embodiment will be described herein. However, in other embodiments, the first electrode 20 may be a cathode electrode, and the second electrode 50 may be an anode electrode.

[0058] The first electrode 20 may include a conductive material having a high work function. The first electrode 20 may be made of a conductive material such as ITO, IZO, ZnO, or In 2 O 3 When the display device 1 is a front-emission organic light-emitting display device, the first electrode 20 may further include a reflective film formed of Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, etc., located below the conductive film having a high work function.

[0059] The pixel defining layer 30 is disposed on the through layer VIA and the first electrode 20. An opening of the pixel defining layer 30 exposes at least a portion of the first electrode 20.

[0060] As described above, the pixel defining layer 30 includes the first pixel defining layer 31 and the second pixel defining layer 32 , and the second pixel defining layer 32 is stacked on the first pixel defining layer 31 .

[0061] In an embodiment, the first pixel defining layer 31 and the second pixel defining layer 32 may be formed of different materials. For example, the first pixel defining layer 31 may be an inorganic layer including an inorganic material, and the second pixel defining layer 32 may be an organic layer including an organic material. In some embodiments, the first pixel defining layer 31 may include a silicon oxide (SiO x ), silicon nitride (SiN x ) and silicon oxynitride (SiON). In some embodiments, the second pixel defining layer 32 may include at least one organic material selected from the group consisting of polyimide resin, epoxy resin, acrylic resin, and the like.

[0062] The first pixel defining layer 31 may be formed to cover the edge of the first electrode 20 and to form an opening partially exposing the first electrode 20. When the width of the first pixel defining layer 31 is greater than the width of the second pixel defining layer 32 and the first pixel defining layer 31 protrudes outward beyond the second pixel defining layer 32, the opening of the pixel defining layer 30 may be substantially defined by the first pixel defining layer 31. The first electrode 20 may contact the organic layer 40 disposed on the first electrode 20 through the opening of the first pixel defining layer 31.

[0063] The first pixel defining layer 31 has an upper surface 31a and a side surface 31b. The side surface 31b of the first pixel defining layer 31 has an inclination angle (e.g., a predetermined inclination angle) and may be formed between the upper surface of the first electrode 20 and the upper surface 31a of the first pixel defining layer 31. In addition, the upper surface 31a of the first pixel defining layer 31 may have an overlapping portion 31a_1 overlapping with the second pixel defining layer 32 and an edge portion 31a_2 exposed by the second pixel defining layer 32.

[0064] The first pixel defining layer 31 and the second pixel defining layer 32 may be in direct contact with each other, and the surface of the first pixel defining layer 31 in contact with the second pixel defining layer 32 may have a surface roughness (e.g., a predetermined surface roughness). The surface roughness of the surface of the first pixel defining layer 31 may be greater than the surface roughness of the upper surface of the first electrode 20. In an embodiment, the surface roughness of the surface of the first pixel defining layer 31 may be formed by plasma treatment. A further detailed description thereof will be given later.

[0065] When the surface of the first pixel defining layer 31 has surface roughness (eg, predetermined surface roughness), the contact area between the first pixel defining layer 31 and the second pixel defining layer 32 can be increased. Therefore, the adhesion between the first pixel defining layer 31 and the second pixel defining layer 32 can be improved.

[0066] In an embodiment, the surface roughness of the first pixel defining layer 31 may be uneven across the surface of the first pixel defining layer 31. In an embodiment, for example, the surface roughness of both the upper surface 31a and the side surface 31b of the first pixel defining layer 31 is greater than the surface roughness of the upper surface of the first electrode 20, and the surface roughness of the upper surface 31a of the first pixel defining layer 31 may be greater than the surface roughness of the side surface 31b of the first pixel defining layer 31.

[0067] In an embodiment, the surface roughness of the upper surface 31a of the first pixel defining layer 31 may also be different in each region. For example, the surface roughness of the overlapping portion 31a_1 of the upper surface 31a of the first pixel defining layer 31 that overlaps with the second pixel defining layer 32 may be different from the surface roughness of the edge portion 31a_2 of the upper surface 31a of the first pixel defining layer 31 that does not overlap with the second pixel defining layer 32 and is exposed from the second pixel defining layer 32. In an embodiment, the surface roughness of the overlapping portion 31a_1 of the upper surface 31a of the first pixel defining layer 31 may be less than the surface roughness of the edge portion 31a_2 of the upper surface 31a of the first pixel defining layer 31.

[0068] The surface roughness may be represented by a contact angle with water. In an embodiment, the water contact angle due to the surface roughness of the surface of the first pixel defining layer 31 may be in the range of 20° to 55°, and in an embodiment, in the range of 40° to 50°.

[0069] As described above, when the surface of the first pixel defining layer 31 has surface roughness (e.g., predetermined surface roughness), the contact area between the first pixel defining layer 31 and the second pixel defining layer 32 increases, and the adhesion between the pixel defining layers 30 can be improved. Therefore, the second pixel defining layer 32 can be prevented or substantially prevented from being peeled off from the first pixel defining layer 31, and the organic layer 40 can be stably formed in a subsequent process, thereby ensuring processability and improving the display quality of the display device.

[0070] In addition, as described later herein, the organic layer 40 may be formed to cover at least a portion of the first electrode 20 and the pixel defining layer 30, and the organic layer 40 may overlap the first electrode 20 and the first pixel defining layer 31 having a surface roughness (e.g., a predetermined surface roughness). In this case, the contact area between the organic layer 40 and the first pixel defining layer 31 increases, and the adhesion between the organic layer 40 and the first pixel defining layer 31 may be further improved.

[0071] The second pixel defining layer 32 may be stacked on the surface of the first pixel defining layer 31 to cover at least a portion of the first pixel defining layer 31. That is, the second pixel defining layer 32 overlaps the first pixel defining layer 31 and may expose at least a portion of the first pixel defining layer 31. The second pixel defining layer 32 may expose the side surface 31b of the first pixel defining layer 31 or expose both the side surface 31b and the edge portion 31a_2 of the upper surface 31a.

[0072] In an embodiment, the thickness of the second pixel defining layer 32 may be greater than the thickness of the first pixel defining layer 31. Since the thickness of the second pixel defining layer 32 is relatively large, when the organic layer 40 corresponding to each pixel 70 is formed, the organic layer forming material may be prevented or substantially prevented from overflowing into adjacent pixels.

[0073] The organic layer 40 may be disposed on the first electrode 20. In an embodiment, the organic layer 40 may include an electron intermediating layer 41, an organic light emitting layer 42, and a hole intermediating layer 43, which are organic material layers included in the display device 1. The embodiments are described herein through such examples.

[0074] The electron intermediary layer 41, the organic light emitting layer 42, and the hole intermediary layer 43 may be arranged in a structure in which three layers are stacked. The hole intermediary layer 43 may be disposed on the first electrode 20, the organic light emitting layer 42 may be disposed on the hole intermediary layer 43, and the electron intermediary layer 41 may be disposed on the organic light emitting layer 42. The electron intermediary layer 41, the organic light emitting layer 42, and the hole intermediary layer 43 may be separately disposed for each pixel, but the present disclosure is not limited thereto.

[0075] The electron intermediating layer 41 may include an electron injection layer EIL and / or an electron transport layer ETL.

[0076] The hole intermediating layer 43 may include a hole injection layer HIL and / or a hole transport layer HTL.

[0077] The hole interposing layer 43 of the organic layer 40 may contact the first electrode 20 and the side surface 31b having the surface roughness (e.g., the predetermined surface roughness) of the first pixel defining layer 31. In addition, the edge of the hole interposing layer 43 may be formed to cover the upper surface 31a of the first pixel defining layer 31, and the hole interposing layer 43 may also contact the edge portion 31a_2 of the upper surface 31a of the first pixel defining layer 31.

[0078] When the hole interposing layer 43 contacts the first pixel defining layer 31 having a surface roughness (e.g., a predetermined surface roughness), the contact area between the first pixel defining layer 31 and the hole interposing layer 43 can be further increased. Therefore, the adhesion between the hole interposing layer 43 and the first pixel defining layer 31 can be further improved.

[0079] Light emission may be performed in the organic light emitting layer 42. When holes and electrons generated by the first and second electrodes 20 and 50 are combined in the organic light emitting layer 42 and excitons formed at this time change their energy levels from an excited state to a ground state, light having a color corresponding to the changed energy level may be emitted.

[0080] The light emitting region as a region where light is emitted may be substantially equal to or smaller than a region where the first electrode 20 and the organic layer 40 overlap each other. That is, the width of the light emitting region may be equal to or smaller than a width where the first electrode 20 and the organic layer 40 overlap each other.

[0081] The organic layer 40 may have a central portion c1 and an edge portion e1. Figure 3 , the central portion c1 is a region where the organic layer 40 is in direct contact with the first electrode 20 , and the edge portion e1 may be defined as a region where the organic layer 40 overlaps the adjacent pixel defining layer 30 .

[0082] The thickness of the edge portion e1 and the thickness of the central portion c1 of the organic layer 40 may be different from each other. The thickness of the edge portion e1 of the organic layer 40 may be partially greater than the thickness of the central portion c1.

[0083] The edge portion e1 of the organic layer 40 may be formed to cover at least a portion of the surface of the first pixel defining layer 31 and / or the second pixel defining layer 32. For example, the edge portion e1 of the organic layer 40 may be formed to cover the side surface 31b of the first pixel defining layer 31 and / or the edge portion 31a_2 of the upper surface 31a of the first pixel defining layer 31. In addition, the edge portion e1 of the organic layer 40 may be in contact with the side surface of the second pixel defining layer 32. Although Figure 3 A case in which the organic layer 40 is formed to partially cover the surfaces of the first pixel defining layer 31 and the second pixel defining layer 32 is shown, but the shape of the organic layer 40 is not limited thereto.

[0084] The central portion c1 of the organic layer 40 may contact the first electrode 20 through the opening defined by the first pixel defining layer 31, and the edge portion e1 of the organic layer 40 may not contact the first electrode 20. In other words, the first pixel defining layer 31 may separate and / or electrically isolate the edge portion e1 of the organic layer 40 from the first electrode 20. If the edge portion e1 of the organic layer 40 is separated from the first electrode 20 by the first pixel defining layer 31, holes may not be injected from the first electrode 20 to the edge portion e1 of the organic layer 40. Therefore, the current from the first electrode 20 may flow only into the central portion c1, and the holes may be uniformly transmitted, so that only the central portion c1 of the organic layer 40 may emit light and the amount of light emitted by the organic layer 40 may be constant, which in turn improves the display quality of the entire display device.

[0085] Figure 4A is a graph showing brightness of a display device according to a comparative example; and Figure 4B is a diagram showing brightness of a display device according to an embodiment.

[0086] exist Figure 4A and Figure 4BIn the figure, the X-axis represents Figure 3 The Y axis represents positions corresponding to the central portion c1 and the edge portion e1 of the organic layer 40 , and the Y axis represents brightness (nit) measured according to the positions of the organic layer 40 . Figure 4A A case is shown in which the pixel defining layer has a single-layer structure and at least a portion of an edge portion of the organic layer overlaps with the first electrode.

[0087] refer to Figure 4A In the display device according to the comparative example, the brightness is concentrated at the boundary between the central portion c1 and the edge portion e1, and thus the brightness of the central portion c1 is presented unevenly. The current is concentrated at the boundary between the central portion c1 and the edge portion e1 and the brightness is highest, and the brightness decreases toward the center. Therefore, the uniformity of light emission is reduced, and the current is concentrated at the boundary between the central portion c1 and the edge portion e1. As a result, the life of the device may be shortened due to the deterioration of the device.

[0088] On the other hand, in the display device 1 according to the embodiment of the present disclosure, since the first pixel defining layer 31 is formed at the edge portion e1 where the current is concentrated, the light emission amount can be kept constant across the central portion c1 as the light emitting area. Therefore, the brightness in the central portion c1 is uniform, and the brightness in the central portion c1 can be much higher than the brightness of the central portion of the comparative example. In addition, the current can be prevented or substantially prevented from being concentrated at the boundary between the central portion c1 and the edge portion e1, thereby preventing or substantially preventing the degradation of the device and improving the display quality of the entire display device.

[0089] Reference again Figures 1 to 3 , the second electrode 50 is disposed on the organic layer 40. When the second electrode 50 is used as a cathode electrode, the second electrode 50 may include a conductive material having a low work function. For example, the second electrode 50 may include Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, or Ca, etc. When the display device 1 is a front-emitting organic light-emitting display device, the second electrode 50 may ensure transparency by forming a conductive film having a low work function as a thin film. In this case, the second electrode 50 may further include an auxiliary electrode, or may further include a conductive film composed of ITO, IZO, ZnO, or In on the conductive film having a low work function. 2 O 3 Transparent conductive film made.

[0090] In an embodiment, the second electrode 50 may be a common electrode formed integrally without distinguishing pixels. In an embodiment, the second electrode 50 may completely cover structures located below the second electrode 50, such as the organic layer 40, the first pixel defining layer 31, and the second pixel defining layer 32. For example, the second electrode 50 located on the organic layer 40 and the second electrode 50 located on the first pixel defining layer 31 and the second pixel defining layer 32 may be connected to each other.

[0091] Some other embodiments of the present disclosure will be described herein. In the following embodiments, components identical to those of the embodiments described above are denoted by identical reference numerals, and further description thereof will be omitted or simplified.

[0092] Figure 5 is a cross-sectional view of a display device according to another embodiment.

[0093] refer to Figure 5 According to the embodiment, the display device 2 and Figure 3 The embodiment of the present invention is similar in that the upper surface 31a of the first pixel defining layer 31 has a surface roughness (eg, a predetermined surface roughness), and Figure 3 The embodiment of FIG. 1 is different in that the side surface 31 b of the first pixel defining layer 31 has a relatively smooth surface.

[0094] That is, the surface roughness of the side surface 31b of the first pixel defining layer 31 is less than the surface roughness of the upper surface 31a of the first pixel defining layer 31, and may be similar to or substantially the same as the surface roughness of the first electrode 20. In an embodiment, the upper surface 31a of the first pixel defining layer 31 is a plasma-treated surface, while the side surface 31b of the first pixel defining layer 31 may not be a plasma-treated surface.

[0095] In the present embodiment, although the side surface 31b of the first pixel defining layer 31 does not have a rough surface, since the upper surface 31a of the first pixel defining layer 31 still has surface roughness (e.g., predetermined surface roughness), the contact area with the second pixel defining layer 32 disposed thereon can be increased. Therefore, the adhesion between the first pixel defining layer 31 and the second pixel defining layer 32 can be improved.

[0096] Figure 6 is a cross-sectional view of a display device according to another embodiment of the present disclosure.

[0097] exist Figure 6 In the display device 3 shown in FIG. 1 , the hole intermediating layer 43 of the organic layer 40 may be formed as a common layer without distinguishing pixels.

[0098] In an embodiment, the hole interposing layer 43 may be continuously disposed on the substrate 10 without distinguishing pixels. Although the hole interposing layer 43 is formed as a common layer, light emission of the organic light emitting element may be performed only in a light emitting region overlapping the organic light emitting layer 42. The hole interposing layer 43 may completely cover structures located below the hole interposing layer 43, such as the first electrode 20, the first pixel defining layer 31, and the second pixel defining layer 32.

[0099] The hole interposing layer 43 may contact the surface of the second pixel defining layer 32 and the surface of the first pixel defining layer 31 exposed by the second pixel defining layer 32. Since the surface of the first pixel defining layer 31 has a surface roughness (e.g., a predetermined surface roughness), the contact area between the first pixel defining layer 31 and the second pixel defining layer 32 and between the first pixel defining layer 31 and the hole interposing layer 43 may be increased, and the adhesion may be improved as described above.

[0100] Figure 7 is a cross-sectional view of a display device according to another embodiment.

[0101] exist Figure 7 In the display device 4 shown in FIG. 1 , the electron intermediating layer 41 of the organic layer 40 may be formed as a common layer without distinguishing pixels.

[0102] In an embodiment, the electron intermediary layer 41 may be continuously disposed on the substrate 10 without distinguishing pixels. Although the electron intermediary layer 41 is formed as a common layer, light emission of the organic light emitting element may be performed only in a light emitting region overlapping the organic light emitting layer 42. The electron intermediary layer 41 may completely cover structures located below the electron intermediary layer 41, such as the first electrode 20, the hole intermediary layer 43, the organic light emitting layer 42, the first pixel defining layer 31, and the second pixel defining layer 32.

[0103] Although not shown in the drawings, according to an embodiment, both the hole intermediating layer 43 and the electron intermediating layer 41 may be formed as a common layer.

[0104] Figure 8 is a cross-sectional view of a display device according to another embodiment.

[0105] refer to Figure 8 According to the display device 5 of this embodiment, Figure 3 The embodiment of FIG. 4 is different in that a metal layer 60 is further disposed on the first pixel defining layer 31 .

[0106] The metal layer 60 is disposed between the first pixel defining layer 31 and the second pixel defining layer 32 ′ and contacts a surface of the first pixel defining layer 31 and a surface of the second pixel defining layer 32 ′.

[0107] The width of the metal layer 60 may be smaller than the width of the pixel defining layer 30. The width of the metal layer 60 may be smaller than the width of the upper surface 31a of the first pixel defining layer 31 and the width of the lower surface of the second pixel defining layer 32'. In an embodiment, the metal layer 60 may be sandwiched between the first pixel defining layer 31 and the second pixel defining layer 32' so that one surface and the other surface of the metal layer 60 may be completely covered by the pixel defining layer 30. The thickness of the metal layer 60 may be smaller than the thickness of the first pixel defining layer 31, but the present disclosure is not limited thereto.

[0108] The metal layer 60 may be in contact with the first pixel defining layer 31 having a surface roughness (e.g., a predetermined surface roughness). For example, the metal layer 60 may be in contact with the upper surface 31a of the first pixel defining layer 31 having a surface roughness (e.g., a predetermined surface roughness). When the surface where the metal layer 60 contacts the first pixel defining layer 31 has a surface roughness (e.g., a predetermined surface roughness), the contact area between the metal layer 60 and the first pixel defining layer 31 may be increased to improve the adhesion between the metal layer 60 and the first pixel defining layer 31.

[0109] The second pixel defining layer 32' may be disposed on the metal layer 60. When the second pixel defining layer 32' is an organic layer, the metal layer 60 and the second pixel defining layer 32' may contact each other, so that the second pixel defining layer 32' may be more firmly attached. That is, the metal layer 60 having strong adhesion to the second pixel defining layer 32' is interposed between the first pixel defining layer 31 and the second pixel defining layer 32', so that the adhesion between the first pixel defining layer 31 and the second pixel defining layer 32' may be further improved. In other words, since the metal layer 60 is further disposed between the pixel defining layers 30, and one surface of the first pixel defining layer 31 has a surface roughness (e.g., a predetermined surface roughness), the adhesion between the pixel defining layers 30 may be further improved. Therefore, as described above, the peeling failure of the second pixel defining layer 32' may be prevented or substantially prevented, and the display quality of the display device may be improved.

[0110] The metal layer 60 may be formed of a conductive material. For example, the metal layer 60 may be formed of the same material as the gate electrode or the source / drain electrode of the thin film transistor or the first electrode 20 .

[0111] In an embodiment, the second pixel defining layer 32' may include a contact hole CT exposing a portion of the metal layer 60. The second electrode 50 may be connected to the metal layer 60 through the contact hole CT. When the metal layer 60 is connected to the second electrode 50, the metal layer 60 may be used as an auxiliary electrode of the second electrode 50. Since the metal layer 60 is electrically connected to the second electrode 50, the resistance of the second electrode 50 may be reduced.

[0112] Fig. 9 is a cross-sectional view of a display device according to another embodiment.

[0113] refer to Fig. 9 , the display device 6 according to the embodiment and Figure 3 The embodiment of FIG. 4 is different in that the first pixel defining layer 31 ′ includes a hole H.

[0114] The first pixel defining layer 31' may include at least one hole H passing through the first pixel defining layer 31' in the thickness direction. The inside of the hole H of the first pixel defining layer 31' may be filled with the second pixel defining layer 32. The second pixel defining layer 32 may be in contact with the inner wall of the hole H, and thus, the contact area between the first pixel defining layer 31' and the second pixel defining layer 32 may be increased. In addition, a portion of the second pixel defining layer 32 is inserted into the hole H, so that the second pixel defining layer 32 is more firmly coupled to the first pixel defining layer 31', thereby preventing or substantially preventing the second pixel defining layer 32 from being peeled off.

[0115] In an embodiment, similar to the surface of the first pixel defining layer 31', the inner wall of the hole H of the first pixel defining layer 31' may have a surface roughness (e.g., a predetermined surface roughness). Therefore, the contact area between the first pixel defining layer 31' and the second pixel defining layer 32 may be further increased. In an embodiment, the surface roughness of the inner wall of the hole H may be greater than the surface roughness of the first electrode 20.

[0116] The hole H may completely penetrate the first pixel defining layer 31' to expose, for example, a layer of the through layer VIA disposed under the first pixel defining layer 31'. The second pixel defining layer 32 filling the hole H may contact a surface of the through layer VIA exposed by the hole H. In an embodiment, when the through layer VIA and the second pixel defining layer 32 are organic layers and the first pixel defining layer 31' is an inorganic layer, by ensuring a contact area between organic layers having relatively strong bonding force through the hole H, adhesion therebetween may be improved.

[0117] The surface of the through layer VIA exposed by the hole H may have surface roughness (eg, predetermined surface roughness). That is, because the surface of the through layer VIA has surface roughness (eg, predetermined surface roughness), adhesion with the second pixel defining layer 32 contacting the through layer VIA may be improved.

[0118] In an embodiment, the surface roughness of the first pixel defining layer 31 ′ may be greater than the surface roughness of the through-layer VIA, and the surface roughness of the through-layer VIA may be greater than the surface roughness of the first electrode 20 .

[0119] FIG. 10A to FIG. 10D2 is a plan view of a display device according to various embodiments, which shows various shapes of a hole H formed in the first pixel defining layer 31 ′.

[0120] refer to Fig. 10A In the embodiment, the hole H is provided between the pixels 70 and may be formed into a linear shape extending in one direction. The planar shape of the hole H may be as follows: Fig. 10A The rectangular shape shown in FIG. 1 is not limited thereto and may be circular or polygonal. Fig. 10A It is shown that the hole H is intermittently formed for each pixel, but the hole H may be continuously formed along the pixel column boundary.

[0121] refer to Fig. 10B In an embodiment, the holes H may be formed in a lattice structure along the boundaries of the pixels 70. The frame of the holes H may be as follows: Fig. 10B , but may also have a shape that includes irregularities in plan view. Fig. 10C As shown in FIG. 1 , the frame of the hole H may include a sawtooth shape. When the frame of the hole H has a sawtooth shape, the surface area of ​​the hole H increases, and the adhesion between the first pixel defining layer 31 ′ and the second pixel defining layer 32 may be further improved.

[0122] refer to Fig. 10D In an embodiment, the hole H is formed along the boundary of each pixel, and a plurality of holes H may be formed to be spaced apart from each other. When a plurality of holes H are formed, the surface area of ​​the hole H may be further increased, and the adhesion between the pixel defining layers 30 may be further improved.

[0123] When the first pixel defining layer 31' includes at least one hole H as described above, the second pixel defining layer 32 may contact the inside of the first pixel defining layer 31' and / or the through layer VIA through the hole H. Therefore, compared with the case where the second pixel defining layer 32 contacts only the upper surface 31a of the first pixel defining layer 31, the contact area between adjacent layers increases, so that the adhesion may be further enhanced. Therefore, the second pixel defining layer 32 may be prevented or substantially prevented from being peeled off from the first pixel defining layer 31', thereby further improving the display quality of the display device.

[0124] A method of manufacturing a display device according to an embodiment will be described herein.

[0125] Figures 11 to 17 is a cross-sectional view showing a task or step of a method for manufacturing a display device according to an embodiment, and more specifically, a cross-sectional view showing a task or step along the Figure 1 A cross-sectional view taken along line II-II'.

[0126] refer to Figures 11 to 17, the tasks or steps of the method for manufacturing a display device according to an embodiment may include: forming a first electrode 20 for each pixel on a substrate 10 including a plurality of pixels; forming a first pixel defining layer 31 disposed on the substrate 10 along a boundary of each pixel to include an opening exposing the first electrode 20; performing plasma treatment 100 on a surface of the first pixel defining layer 31; forming a second pixel defining layer 32 on the surface of the first pixel defining layer 31; forming an organic layer 40 disposed on the first electrode 20 in the opening of the pixel defining layer 30; and forming a second electrode 50 on the organic layer 40.

[0127] First, refer to Fig.11 , the first electrode 20 is formed on the substrate 10 including a plurality of pixels. The first electrode 20 is formed for each pixel. For ease of description, although the first electrode 20 is shown in the drawings as being directly formed on the substrate 10, the buffer layer 11, the thin film transistor, the through layer VIA, etc. may be provided between the substrate 10 and the first electrode 20.

[0128] Then, refer to Fig.12 The first pixel defining layer 31 is formed on the substrate 10 on which the first electrode 20 is formed. The first pixel defining layer 31 is completed by forming an inorganic layer on the substrate 10 and then etching the inorganic layer. The inorganic layer includes, for example, silicon oxide (SiO x ) layer, silicon nitride (SiN x The patterned first pixel defining layer 31 is disposed along the boundary of the pixel and includes an opening partially exposing the first electrode 20.

[0129] Then, refer to Fig.13 , a plasma treatment 100 is performed on the surface of the first pixel defining layer 31. Through the plasma treatment 100, a surface roughness (e.g., a predetermined surface roughness) is imparted to the surface of the first pixel defining layer 31. The plasma treatment 100 may be performed under the condition that the surface of the first pixel defining layer 31 has a surface roughness greater than that of the first electrode 20 while minimizing or reducing surface damage of the first electrode 20.

[0130] In an embodiment, the plasma process 100 may use a plasma containing O 2 and N 2 The surface roughness of the first pixel defining layer 31 and the degree of surface damage of the first electrode 20 can be determined according to the plasma generation gas. 2 and N 2 For example, if the plasma generation gas contains N 2 The proportion of gas is greater than that of O in the plasma generation gas. 2If the ratio of the gas is less than 1%, the damage of the first electrode 20 can be prevented or substantially prevented when the surface roughness (eg, predetermined surface roughness) is imparted to the surface of the first pixel defining layer 31. 2 Gas and O 2 The composition ratio of the gas can be adjusted within the range of 9:1 to 99:1. 2 Gas and O 2 O in gas mixture 2 If the ratio of the gas is adjusted to 10% or less, the first electrode 20 can be prevented or substantially prevented from being damaged by preventing or substantially preventing the etching selectivity for the first electrode 20 made of an oxide such as ITO from increasing. 2 Gas and O 2 O in gas mixture 2 When the ratio of the gas is 1% or more, it is advantageous to reduce the processing time of the plasma processing 100 for ensuring the surface roughness.

[0131] Then, refer to Fig.14 , the second pixel defining layer 32 is formed on the surface of the first pixel defining layer 31. In an embodiment, the second pixel defining layer 32 may be formed by forming an organic layer on the substrate 10 and then patterning the organic layer through an exposure and development process, the organic layer comprising at least one organic material selected from the group consisting of benzocyclobutene (BCB), polyimide (PI), polyamide (PA), acrylic resin, and phenolic resin. Since the second pixel defining layer 32 is formed on the surface of the first pixel defining layer 31 roughened by the plasma treatment 100, as described above, the adhesion with the first pixel defining layer 31 may be improved.

[0132] Then, the organic layer 40 is formed on the first electrode 20 exposed by the opening of the pixel defining layer 30. In an embodiment, the organic layer 40 may be formed by inkjet printing. Fig.15 and Fig.16 A method of forming the organic layer 40 by inkjet printing is described in further detail.

[0133] refer to Fig.15, the task or step of forming the organic layer 40 by inkjet printing may include preparing an organic layer forming ink 40' including a solvent and an organic material dispersed in the solvent, and applying the organic layer forming ink 40' to each pixel 70 using the inkjet printing device 200. In an embodiment, the organic layer forming ink 40' is prepared by dissolving the organic material of the organic layer 40 in a solvent, and the organic layer forming ink 40' is discharged from the inkjet printing device 200 and applied to each area defined by the pixel defining layer 30. For example, the organic layer forming ink 40' may be applied to contact the surface of the first electrode 20 through the opening of the pixel defining layer 30. The organic layer forming ink 40' may be discharged from the inkjet printing device 200 and applied to contact the surface of the first electrode 20, the side surface of the second pixel defining layer 32, the side surface 31b of the first pixel defining layer 31, and the edge portion 31a_2 of the upper surface 31a of the first pixel defining layer 31 exposed by the second pixel defining layer 32.

[0134] Then, refer to Fig.16 , the solvent of the organic layer forming ink 40' is dried to form the organic layer 40 for each pixel 70. In some embodiments, the thickness of the organic layer 40 after drying may be different for each region. The thickness of the organic layer 40 may be defined as the shortest distance among the vertical distances from the lower surface to the upper surface of the organic layer 40. For example, the thickness of the central portion c1 of the organic layer 40 may be different from the thickness of the edge portion e1 of the organic layer 40, and the thickness of the edge portion e1 may be partially greater than the thickness of the central portion c1.

[0135] Then, refer to Fig.17 , the second electrode 50 is formed on the organic layer 40. In an embodiment, the second electrode 50 is formed by a deposition process, and for example, vacuum deposition or sputtering may be used, but the present disclosure is not limited thereto. By forming the second electrode 50, the following can be accomplished: Figure 3 The display device 1 shown in FIG.

[0136] Hereinafter, a method of manufacturing a display device according to another embodiment of the present disclosure will be described. Redundant descriptions may be omitted, and differences will be mainly described.

[0137] Fig.18 and Fig.19 is a cross-sectional view illustrating tasks or steps of a method of manufacturing a display device according to another embodiment.

[0138] Fig.18 and Fig.19 Show manufacturing basis Figure 5 Some tasks or steps of the method of the display device of the embodiment. Figures 11 to 17 The embodiment differs in that the execution forms Fig.11The first electrode 20 is formed by performing a plasma treatment 100 on the surface of the inorganic layer 31_1 and then etching the inorganic layer 31_1 to form the first pixel defining layer 31 .

[0139] refer to Fig.18 , until the task or step of forming the first electrode 20 on the substrate 10 and forming the inorganic layer 31_1 thereon is the same as the task or step of Fig.11 and Fig.12 Afterwards, before patterning the inorganic layer 31_1 , a plasma treatment 100 is performed on the surface of the inorganic layer 31_1 .

[0140] The plasma process 100 may be performed in the same manner as in reference Fig.13 The plasma treatment 100 is performed in the same manner as described above, but may be performed under other conditions that can increase the plasma treatment rate. That is, in this task or step, since the plasma treatment 100 is performed while the first electrode 20 is covered and protected by the inorganic layer 31_1, the first electrode 20 is less likely to be damaged by the plasma. Therefore, since the reference ions may not be considered in this task or step, Fig.13 The damage prevention conditions of the first electrode 20 described above can be used to design the process conditions more freely. For example, it is possible to select the O 2 A method of reducing the time required to ensure surface roughness by increasing the content by 10% or more.

[0141] Then, refer to Fig.19 , the inorganic layer 31_1 having a surface roughness (e.g., a predetermined surface roughness) is etched. As a result, the first pixel defining layer 31 including an opening exposing the first electrode 20 is completed. Since the etching process is performed after the plasma treatment 100, the upper surface 31a of the first pixel defining layer 31 has a surface roughness (e.g., a predetermined surface roughness). However, since the side surface 31b of the first pixel defining layer 31 is a surface that is not subjected to the plasma treatment 100, it can have a smoother surface.

[0142] Afterwards, if Figure 5 The display device 2 shown in FIG. 1 can be connected to the display device 2 by performing the following Figures 14 to 17 The manufacturing process is performed by performing the essentially same tasks or steps in the manufacturing process.

[0143] However, the aspects and effects of the embodiments of the present disclosure are not limited to those set forth herein. The above and other aspects and effects of the embodiments will become more apparent to those skilled in the art to which the embodiments belong by referring to the claims.

Claims

1. A display device, include: substrate; a plurality of pixels disposed on the substrate; a first electrode disposed on the substrate for each pixel in the plurality of pixels; a pixel defining layer, located on the substrate along a boundary of each pixel, and comprising an opening exposing the first electrode of each pixel; an organic layer located on the first electrode in the opening of the pixel defining layer; as well as a second electrode located on the organic layer, The pixel defining layer includes a first pixel defining layer and a second pixel defining layer stacked on a surface of the first pixel defining layer. wherein the surface of the first pixel defining layer includes an upper surface and a side surface, wherein the upper surface of the first pixel defining layer includes an overlapping portion and an edge portion, the overlapping portion is a region overlapping with the second pixel defining layer, and the edge portion is a region outside the overlapping portion, and The surface roughness of the overlapping portion of the upper surface of the first pixel defining layer is greater than the surface roughness of the first electrode. 2 . The display device according to claim 1 , wherein the surface roughness of the upper surface of the first pixel defining layer is greater than the surface roughness of the side surface of the first pixel defining layer.

3. The display device according to claim 1, wherein the organic layer includes a central portion and an edge portion, wherein the central portion of the organic layer contacts the first electrode in the opening of the pixel defining layer, wherein the edge portion of the organic layer contacts the side surface of the first pixel defining layer and the edge portion of the upper surface of the first pixel defining layer, and The surface roughness of the side surface of the first pixel defining layer and the edge portion of the upper surface of the first pixel defining layer is greater than the surface roughness of the first electrode. The display device according to claim 3 , wherein the upper surface of the first pixel defining layer is plasma treated.

5. The display device according to claim 1, further comprising a through layer between the first electrode and the substrate, The first pixel defining layer is in direct contact with an upper surface of the through layer.

6. A display device, include: substrate; a plurality of pixels disposed on the substrate; a first electrode disposed on the substrate for each pixel in the plurality of pixels; a pixel defining layer, located on the substrate along a boundary of each pixel, and comprising an opening exposing the first electrode of each pixel; an organic layer located on the first electrode in the opening of the pixel defining layer; as well as a second electrode disposed on the organic layer, The pixel defining layer includes a first pixel defining layer and a second pixel defining layer stacked on a surface of the first pixel defining layer. wherein the surface of the first pixel defining layer includes an upper surface and a side surface, wherein the upper surface of the first pixel defining layer includes an overlapping portion and an edge portion, the overlapping portion is a region overlapping with the second pixel defining layer, and the edge portion is a region outside the overlapping portion, and The water contact angle of the overlapping portion of the upper surface of the first pixel defining layer is greater than the water contact angle of the first electrode.

7. The display device according to claim 6, in, A water contact angle of the overlapping portion of the upper surface of the first pixel defining layer is smaller than a water contact angle of the edge portion of the upper surface of the first pixel defining layer.

8. The display device according to claim 6, wherein the organic layer includes a central portion and an edge portion, wherein the central portion of the organic layer contacts the first electrode in the opening of the pixel defining layer, wherein the edge portion of the organic layer contacts the side surface of the first pixel defining layer and the edge portion of the upper surface of the first pixel defining layer, and The water contact angles of the side surface of the first pixel defining layer and the edge portion of the upper surface of the first pixel defining layer are greater than the water contact angle of the first electrode. 9 . The display device of claim 6 , wherein a water contact angle of the first pixel defining layer is from 20° to 55°.

10. The display device according to claim 6, further comprising a through layer between the first electrode and the substrate, The first pixel defining layer is in direct contact with an upper surface of the through layer.

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