Light emitting display device and method of manufacturing the same

Abstract

Disclosed are a light emitting display device and a method of manufacturing the light emitting display device, the light emitting display device including: a substrate including a first sub-pixel and a second sub-pixel; a light emitting element on the substrate; a first cap layer disposed on the second electrode of the light emitting element; a metal pattern on the first cap layer and corresponding to the first sub-pixel; and a refractive pattern on the first cap layer and corresponding to the second sub-pixel.

Description

[0001] This application claims the benefit of Korean Patent Application No. 10-2023-0095428, filed on Jul. 21, 2023, which is incorporated herein by reference as if fully set forth herein. Technical Field

[0002] The present disclosure relates to a light-emitting display device, and more particularly, to a light-emitting display device capable of reducing a sharp change in brightness depending on a viewing angle and manufacturing the light-emitting display device. Background Art

[0003] With the advent of the information society, displays for visually expressing electrical information signals have been rapidly developed. In response to this, various display devices having excellent performance such as slimness, reduced weight, and reduced power consumption are being studied and developed.

[0004] Among them, the light-emitting display device includes a light-emitting element capable of spontaneously emitting light, and thus does not require a separate light source used in a non-light-emitting element, thereby achieving reduced weight and thickness. Summary of the invention

[0005] The light emitting element includes an intermediate layer between a first electrode and a second electrode, and emits light when an electric field is applied between the first electrode and the second electrode.

[0006] The light emitted from the intermediate layer propagates toward the front surface, the rear surface, and the side surface, and the first electrode is formed of a reflective electrode, thereby finally allowing the light to travel to the front surface and the side surface. Among them, the emitted light traveling to the side surface may not be emitted by a structure such as a dam, and may be captured inside. Such a light-emitting display device may have a problem in which the brightness of the side surface is rapidly reduced compared to the front surface depending on the viewing angle of the viewer.

[0007] Accordingly, the present disclosure is directed to a light emitting display device that substantially obviates one or more problems due to limitations and disadvantages of the related art.

[0008] An object of the present disclosure is to provide a light-emitting display device capable of selectively reducing a microcavity effect of a sub-pixel and reducing a brightness deviation between a front surface and a side surface, thereby reducing a rapid change in brightness depending on a viewing angle.

[0009] Additional advantages, purposes and features of the present disclosure will be set forth in part in the following description, and in part will become apparent to those of ordinary skill in the art upon review of the following, or may be learned from the practice of the present disclosure. The purposes and other advantages of the present disclosure may be realized and obtained through the structures particularly pointed out in the written description and claims of the present disclosure and the accompanying drawings.

[0010] The light emitting display device according to the present disclosure has a refraction pattern on a second electrode of a selected sub-pixel and has a metal pattern on the second electrodes of sub-pixels other than the selected sub-pixel, thereby reducing a microcavity effect of the selected sub-pixel.

[0011] Preferably, the light emitting display device according to the present disclosure further includes a metal pattern on the refraction pattern of the selected sub-pixel, and the metal pattern of the selected sub-pixel is made thinner than metal patterns of other sub-pixels, thereby reducing the microcavity effect of the selected sub-pixel.

[0012] According to an embodiment of the present disclosure, a light-emitting display device includes: a substrate including a first sub-pixel and a second sub-pixel; a light-emitting element on the substrate; a first cover layer arranged on the second electrode of the light-emitting element; a metal pattern, which is (arranged) on the first cover layer and corresponds to the first sub-pixel; and a refraction pattern, which is (arranged) on the first cover layer and corresponds to the second sub-pixel.

[0013] According to an embodiment of the present disclosure, a method for manufacturing a light-emitting display device includes: forming a substrate including a first sub-pixel and a second sub-pixel; forming a light-emitting element on the substrate; forming a first cover layer on the second electrode of the light-emitting element; forming a refraction pattern on the first cover layer of the second sub-pixel; and forming a metal pattern on the first cover layer of the first sub-pixel.

[0014] It is to be understood that both the foregoing general description and the following detailed description of the present disclosure are exemplary and explanatory and are intended to provide further explanation of the disclosure as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings, which are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this application, illustrate embodiments of the present disclosure and together with the description serve to explain the principles of the present disclosure. In the drawings:

[0016] Figure 1 is a cross-sectional view showing a light emitting display device according to a first embodiment of the present disclosure;

[0017] Figure 2 is a graph showing brightness versus viewing angle;

[0018] FIG. 3A to FIG. 3D It shows the manufacturing Figure 1 A cross-sectional view of a process of a light emitting display device; and

[0019] Figure 4 is a cross-sectional view showing a light emitting display device according to a second embodiment of the present disclosure. DETAILED DESCRIPTION

[0020] With reference to the accompanying drawings, the advantages and features of the present disclosure and their implementation methods will be clearly understood according to the following preferred embodiments. However, the present disclosure is not limited to these embodiments and can be implemented in different forms. These embodiments are proposed only to provide a thorough and complete understanding of the disclosed context and to fully inform those skilled in the art of the technical concept of the present disclosure, and the embodiments of the present disclosure are limited only by the scope of the claims.

[0021] The shapes, sizes, ratios, angles, numbers, etc. shown in the drawings for illustrating various embodiments of the present disclosure are provided for illustration only, and the present disclosure is not limited to the contents shown in the drawings. Where possible, the same reference numerals will be used in the drawings to refer to the same or similar parts. In the following description, a detailed description of the technology or configuration related to the present disclosure may be omitted to avoid unnecessarily obscuring the subject matter of the present disclosure.

[0022] When terms such as "including," "having," and "comprising" are used in the disclosure, additional components may be present unless "only" is used. Components described in the singular include plural components unless specifically stated otherwise.

[0023] Even if there is no additional specific description of the components included in the embodiments of the present disclosure, the components included in the embodiments of the present disclosure should be construed to include an error range.

[0024] When describing various embodiments of the present disclosure, when terms describing positional relationships (for example, "on," "above," "below," and "close to") are used, at least one intermediate element may be present between two elements, unless "immediately" or "directly" is also used.

[0025] When describing various embodiments of the present disclosure, when terms related to a time relationship are used (for example, "after," "subsequently," "next," and "before"), discontinuities may be included unless "immediately" or "directly" is also used.

[0026] When describing various embodiments of the present disclosure, terms such as "first" and "second" may be used to describe various components, but these terms are intended only to distinguish identical or similar components from one another and may not define an order or sequence. Therefore, in the disclosure, unless otherwise specifically mentioned, a "first" component may be the same as a "second" component within the technical concept of the present disclosure.

[0027] The terms “first horizontal axis direction”, “second horizontal axis direction”, and “vertical axis direction” should not be interpreted only as a vertical geometric relationship with each other, but have a wider range of directions as long as the configuration of the present disclosure can function functionally.

[0028] The term "at least one" should be understood to include all possible combinations of one or more related items. For example, "at least one of the first, second, and third items" refers to each of the first, second, or third items, and any combination of two or more of the first, second, and third items.

[0029] The features of various embodiments of the present disclosure may be partially or completely coupled or combined with each other, and may interoperate with each other in various ways and be driven technically. The embodiments of the present disclosure may be performed independently of each other, or may be performed together in an interrelated manner.

[0030] When adding reference numerals to components in each figure, the same components may have the same reference numerals as much as possible even if they are shown in different figures. In addition, for ease of explanation, the scales of the components shown in the drawings have a scale different from the actual scale, and therefore are not limited to the scales shown in the drawings.

[0031] Furthermore, all components of each display device or apparatus according to all embodiments of the present disclosure may be operably coupled and configured.

[0032] Hereinafter, preferred examples of a light emitting display device according to an embodiment of the present disclosure will be described in detail with reference to the accompanying drawings.

[0033] Figure 1 is a cross-sectional view showing a light emitting display device according to a first embodiment of the present disclosure.

[0034] Reference Figure 1 , a light-emitting display device according to the present disclosure includes: a substrate 10 including a plurality of sub-pixels PXL1, PXL2, and PXL3; a thin film transistor TFT on the substrate 10; a light-emitting element 110 on the thin film transistor TFT; a capping structure 120 including a first capping layer 121, a second capping layer 123, and a third capping layer 125 on the light-emitting element 110; and a refraction pattern 140 and a metal pattern 130 disposed in the same layer between the first capping layer 121 and the second capping layer 123. Here, the refraction pattern 140 may be disposed in a region corresponding to the second sub-pixel PXL2, and the metal pattern 130 may be disposed in the first sub-pixel PXL1 and the third sub-pixel PXL3 where the refraction pattern 140 is not disposed.

[0035] The substrate 10 is divided into a display area where a picture appears and a peripheral area where the picture does not appear, and the display area may include a plurality of sub-pixels PXL1, PXL2, and PXL3 arranged repeatedly. The sub-pixels PXL1, PXL2, and PXL3 may include a light-emitting portion that actually emits light, and a non-light-emitting region that does not emit light around the light-emitting portion. For example, when the substrate 10 is a plastic substrate, it may include polyimide or polyamide.

[0036] Sub-pixels PXL1, PXL2, and PXL3 may be defined in a display area by gate lines and data lines formed in a matrix on a substrate and intersecting each other at the same time. Sub-pixels PXL1, PXL2, and PXL3 may include first to third sub-pixels PXL1, PXL2, and PXL3 that emit different colors. The first sub-pixel PXL1 may emit red light, the second sub-pixel PXL2 may emit green light, and the third sub-pixel PXL3 may emit blue light. In addition, the plurality of sub-pixels PXL1, PXL2, and PXL3 may also include sub-pixels that emit white light.

[0037] On the substrate 10, various signal lines such as data signal lines and gate signal lines, transistors such as switching thin film transistors and driving thin film transistors, and circuit elements including capacitors may be formed in each sub-pixel PXL1, PXL2, and PXL3. For ease of description, a single thin film transistor TFT that drives one light emitting portion may be provided.

[0038] The thin film transistor TFT includes: an active layer 37 ; a gate electrode 43 overlapping a channel region 35 of the active layer 37 with a gate insulating film 41 therebetween; and a source electrode 51 and a drain electrode 53 connected to both sides of the active layer 37 .

[0039] The active layer 37 of the thin film transistor TFT includes a source region 31 and a drain region 33 on both sides thereof, wherein a channel region 35 is between the source region 31 and the drain region 33. Each of the source region 31 and the drain region 33 is formed of a semiconductor material doped with n-type or p-type impurities. The channel region 35 overlapping the gate electrode 43 may be formed of a semiconductor material not doped with n-type or p-type impurities.

[0040] The gate electrode 43 of the thin film transistor TFT is arranged to overlap with the channel region 35 of the active layer 37, and has the same width as the channel region 35, wherein the gate insulating film 41 is placed between the gate electrode 43 and the channel region 35. The gate insulating film 41 overlaps with the channel region 35 of the active layer 37 in the same pattern as the gate electrode 43. For example, the gate electrode 43 can be a single layer or multiple layers containing one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd) and copper (Cu) or an alloy thereof. At the same time, the gate insulating film 41 can contain an inorganic insulating material, and can include, for example, a silicon oxide film (SiOx), a silicon nitride film (SiNx), a silicon oxynitride film (SiOxNy) or a plurality of films thereof.

[0041] Meanwhile, the light blocking layer 21 on the substrate 10 overlaps at least the channel region 35 of the active layer 37 of the thin film transistor TFT and is disposed below the active layer 37. The light blocking layer 21 prevents external light from penetrating the substrate 10 and being transmitted to the thin film transistor TFT. For example, the light blocking layer 21 may be a single layer containing a metal material such as molybdenum (Mo), titanium (Ti), aluminum neodymium (AlNd), aluminum (Al), chromium (Cr) or an alloy thereof, or a multilayer structure using the same.

[0042] The buffer film 20 on the light blocking layer 21 is disposed to cover the light blocking layer 21. For example, the buffer film 20 may have a single layer or multi-layer structure including silicon oxide (SiOx) or silicon nitride (SiNx).

[0043] The interlayer insulating film 30 on the buffer film 20 includes a source contact hole and a drain contact hole that expose each of the source region 31 and the drain region 33 of the active layer 37, and covers the gate insulating film 41 and the gate electrode 43. For example, the interlayer insulating film 30 may include an inorganic insulating material. For example, the interlayer insulating film 30 may be a single layer or multiple layers of a silicon oxide film (SiOx), a silicon nitride film (SiNx), or a silicon oxynitride film (SiOxNy).

[0044] The source electrode 51 and the drain electrode 53 may be provided in the same layer on the interlayer insulating film 30. Each of the source electrode 51 and the drain electrode 53 is connected to the source region 31 and the drain region 33 of the active layer 37 through the source contact hole and the drain contact hole. For example, the source electrode 51 and the drain electrode 53 may be a single layer containing a metal material such as molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), copper (Cu), or an alloy thereof, or a multilayer structure using the same.

[0045] A passivation layer 40 on the interlayer insulating film 30 may be provided to cover the region of the thin film transistor TFT. Therefore, the region of the thin film transistor TFT may be protected by the passivation layer 40. For example, the passivation layer 40 is an inorganic insulating film and may be provided as a single layer or multiple layers of a silicon oxide film (SiOx), a silicon nitride film (SiNx), or a silicon oxynitride film (SiOxNy).

[0046] A planarization layer 50 may be provided on the passivation layer 40. The planarization layer 50 is formed to a thickness sufficient to planarize the surface step at the top of the thin film transistor TFT, and may be formed of an organic insulating film. In some cases, when the planarization layer 50 also plays a role in protecting the thin film transistor TFT, the passivation layer 40 may be omitted. For example, the planarization layer 50 is an organic insulating film, and may be any one of photo-acrylic, polyimide, benzocyclobutene resin, and acrylate. In some cases, the planarization layer 50 may be formed as a plurality of layers.

[0047] A light emitting element 110 including a stacked structure of a first electrode 111, an intermediate layer 113, and a second electrode 115 may be provided on the planarization layer 50. The first electrode 111 of the light emitting element 110 may be provided in each of the plurality of sub-pixels PXL1, PXL2, and PXL3, and may be connected to the thin film transistor TFT through the contact hole 55. The light emitting element 110 may operate based on a mechanism in which, when current is supplied from a power voltage line to the second electrode 115 and a high voltage current is supplied from the thin film transistor TFT to the first electrode 111, an electric field is formed between the first electrode 111 and the second electrode 115, and the intermediate layer 113 emits light.

[0048] The light emitting element 110 can be formed in a top emission, bottom emission or dual emission manner according to its structure. The light emitting display device according to the present disclosure can be formed in a top emission manner, wherein the first electrode 111 serves as an electrode with high reflection efficiency to emit light in a direction opposite to the substrate 10.

[0049] Therefore, the first electrode 111 may be formed as a multilayer structure including an opaque conductive film and a transparent conductive film having high reflection efficiency. The transparent conductive film of the first electrode 111 includes a material having a relatively high work function value, such as indium tin oxide (ITO) or indium zinc oxide (IZO), and the opaque conductive film may be a single layer containing any one selected from the group consisting of silver (Ag), aluminum (Al), copper (Cu), molybdenum (Mo), titanium (Ti), nickel (Ni), chromium (Cr), tungsten (W) and alloys thereof, or multiple layers. When the first electrode 111 is formed as a transparent conductive film made of a material having a relatively high work function contacting the intermediate layer 113, hole injection from the first electrode 111 to the intermediate layer 113 may be easy. For example, the first electrode 111 may have a structure in which a transparent conductive film, an opaque conductive film, and a transparent conductive film are sequentially stacked, or a structure in which a transparent conductive film and an opaque conductive film are sequentially stacked.

[0050] The second electrode 115 opposite to the first electrode 111 can be formed on the intermediate layer 113 over the entire substrate 10 through a common mask. For example, the second electrode 115 can be made of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO), and can be made of silver (Ag), aluminum (Al), magnesium (Mg) or calcium (Ca) or an alloy thereof having a thickness small enough to transmit light. Here, in order to make the light-emitting display device according to the present disclosure have a microcavity effect, the second electrode 115 can be formed as a semi-transmissive and semi-reflective electrode (transflectiveelectrode) that transmits some light while reflecting other light. The second electrode 115 can be formed as a semi-transmissive and semi-reflective electrode having a higher transmittance than the first electrode 111. In other words, the second electrode 115 of the light-emitting display device according to the present disclosure is made of silver (Ag), aluminum (Al), magnesium (Mg) or calcium (Ca) or an alloy thereof having a thickness sufficient to transmit light.

[0051] The first electrode 111 and the second electrode 115 may reflect the light generated from the intermediate layer 113 multiple times, and cause destructive interference and constructive interference between the reflected light. As a result of destructive interference and constructive interference, a microcavity effect may occur, that is, a phenomenon in which only light of a predetermined wavelength is maintained while the intensity of light of other wavelengths is weakened. When the inherent vibration of the light-emitting layer arranged in each sub-pixel matches the optical length (e.g., the thickness of the intermediate layer 113) between the first electrode 111 and the second electrode 115, the microcavity effect occurs. Here, the optical length may vary not only according to the thickness of the intermediate layer 113, but also according to the components with different refractive indices arranged on the second electrode 115. For example, the optical length may be adjusted by a cover layer structure 120 including a first cover layer 121, a second cover layer 123, and a third cover layer 125 on the second electrode 115, and a refraction pattern 140 or a metal pattern 130. Therefore, the light-emitting display device according to the present disclosure can increase or adjust the microcavity effect by adjusting the optical length, and has the effect of improving light emission efficiency, such as increasing brightness.

[0052] In addition, among the light generated in the intermediate layer 113, the light traveling to the side surface is captured inside by the structure in the light-emitting element 110, such as the embankment 150, so the brightness on the side surface may be lower than that on the front surface. In particular, the brightness of the front surface and the side surface can be increased by the microcavity effect caused by the first electrode 111 and the second electrode 115, respectively. Therefore, the brightness difference between the front surface and the side surface can be maximized, and the brightness can drop sharply toward the side surface. In addition, the change in brightness can also produce a change in color by causing a change in the brightness of the color itself. For example, in a light-emitting display device, due to the structure in the light-emitting element 110, the microcavity effect can affect the brightness viewing angle and the color viewing angle depending on the brightness viewing angle.

[0053] Here, the light-emitting display device according to the present disclosure has a metal pattern 130 and a refraction pattern 140 selectively disposed in each sub-pixel through a first cover layer 121 disposed on the second electrode 115 of the light-emitting element 110 to minimize the brightness and color difference between the front surface and the side surface. The refraction pattern 140 may be disposed in the second sub-pixel PXL2, and the metal pattern 130 may be disposed in the first sub-pixel PXL1 and the third sub-pixel PXL3 without the refraction pattern 140, but the present disclosure is not limited thereto. If the refraction pattern 140 affects the brightness reduction as follows, the refraction pattern 140 may be disposed in the first sub-pixel PXL1 and the third sub-pixel PXL3 instead of the metal pattern 130. In addition, although Figure 1The refraction pattern 140 and the metal pattern 130 are shown to have the same thickness, but their thicknesses may be different as needed. Depending on a predetermined refractive index in each sub-pixel, the refraction pattern 140 and the metal pattern 130 may have different thicknesses.

[0054] For example, the refraction pattern 140 may include an organic material having a higher transmittance than the second electrode 115, and the metal pattern 130 may be made of the same material as the second electrode 115, or may be made of a metal having the same transmittance as the second electrode 115. The metal pattern 130 may reflect light emitted from the intermediate layer 113, thereby providing a microcavity effect for each of the first electrode 111 and the second electrode 115. In other words, when the light-emitting display device according to the present disclosure has the metal pattern 130, it can increase the amount of light that can be vacuumed to provide a microcavity effect, compared to when only the first electrode 111 and the second electrode 115 are provided, thereby improving the microcavity effect. On the other hand, the refraction pattern 140 has a predetermined refractive index and may reflect some of the light emitted from the intermediate layer 113, but transmits more light than it reflects, and reduces the microcavity effect, compared to the metal pattern 130.

[0055] The second sub-pixel PXL2 selected to have the refraction pattern 140 may exist in a relatively high proportion relative to all sub-pixels. For example, the first to third sub-pixels PXL1, PXL2, and PXL3 may emit one of red, green, and blue light, respectively. The second sub-pixel PXL2 selected to have the refraction pattern 140 may emit green light. Among the three primary colors used to emit white light, green may exist in a larger proportion than red and blue. In some cases, green may exist in a proportion of 50% or more, or 60% or more, or 70% or more. In this way, the green sub-pixel existing in a large proportion can be relatively well perceived by the user, and the brightness change depending on the viewing angle can also be well perceived by the user. Therefore, the light-emitting display device according to the present disclosure selectively reduces the microcavity effect of the green sub-pixel, which is easier to be recognized by the user than other sub-pixels, thereby preventing the brightness of the entire sub-pixel from decreasing rapidly depending on the viewing angle. However, examples of various structures in which a light-emitting display device according to the present disclosure includes a refraction pattern 140 in the second subpixel PXL2 and a metal pattern 130 in the first subpixel PXL1 and the third subpixel PXL3 are shown, and in some cases, the second subpixel PXL2 can emit light of different colors and the refraction pattern 140 can be set in two or more subpixels, but the light-emitting display device is not limited thereto.

[0056] In other words, the light-emitting display device according to the present disclosure may have a refraction pattern 140 in the second sub-pixel PXL2, and the refraction pattern 140 has a relatively large effect on the brightness reduction depending on the viewing angle to provide a relatively low microcavity effect. Therefore, the light-emitting display device of the present disclosure can reduce the brightness difference between the front surface and the side surface of the second sub-pixel PXL2 by the refraction pattern 140, thereby minimizing the sudden drop in the overall brightness depending on the viewing angle. For example, the light-emitting display device of the present disclosure can change the brightness relatively consistently according to the change of the observer's position by improving the brightness viewing angle. In addition, the light-emitting display device of the present disclosure can have the effect of improving the color viewing angle and improving the brightness viewing angle.

[0057] In addition, the refraction pattern 140 may be made of an organic material having a low affinity for the material of the metal pattern 130 to serve as a mask for the metal pattern 130. Here, the fact that the refraction pattern 140 serves as a mask for the metal pattern 130 means that the metal pattern 130 can be used without a separate mask when the refraction pattern 140 is provided. For example, the refraction pattern 140 may be formed of an organic material including an organic polymer, and may include a polycyclic aromatic compound including at least one heteroatom of N (nitrogen), S (sulfur), O (oxygen), phosphorus (P), or aluminum (Al). The polycyclic aromatic compound may include an organic molecule including a core portion and at least one terminal portion bonded to the core portion. For example, the material used for the refraction pattern 140 is 3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ), bis(2-methyl-8-quinolyl)-4-phenylphenol aluminum (III) (BA1q), 2-(4-(9,10-di(naphthalene-2-yl)anthracen-2-yl)phenyl)-1-phenyl-1H-benzo-[D]imidazole (LG201), 8-hydroxyquinoline lithium (Liq), and N(diphenyl-4-yl)9,9-dimethyl-N-(4(9-phenyl-9H-carbaso-3-yl)phenyl)-9H-fluorene-2-amine (HT211), etc.

[0058] In this case, the refraction pattern 140 may have a low affinity for the conductive material and may have a surface that inhibits deposition of the metal pattern 130 of the conductive material. The conductive material for the metal pattern 130 may be probabilistically fixed to the surface of the refraction pattern 140 through a nucleation and growth process during a deposition process. As described above, the conductive material may have a very low surface adhesion probability to the surface of the refraction pattern 140. Therefore, due to the low surface adhesion probability to the refraction pattern 140, the conductive material may be separated from the surface of the refraction pattern 140 during the nucleation and growth process, and thus may not be formed.

[0059] Here, in the case of depositing a conductive material, the surface adhesion probability can be measured by depositing the amount of conductive material required to form a closed-pack layer having an average thickness of 1 nm on the surface of the refraction pattern 140. Specifically, the conductive material is deposited on the surface of the refraction pattern 140 at the same time, and when the average thickness of the layer concentrated on the surface of the refraction pattern 140 reaches 1 nm, the average thickness of the conductive material deposited on the substrate is compared to obtain the probability of surface adhesion of the conductive material for the refraction pattern 140. The probability of surface adhesion of the conductive material to the refraction pattern 140 may be at most 0.3 (or 30%) and at most 0.0008 (or 0.08%) or less. The probability of surface adhesion can be adjusted by changing the material of the refraction pattern 140, the material of the metal pattern 130, or the deposition conditions. The light-emitting display device according to the first embodiment does not have the metal pattern 130 on the surface of the refraction pattern 140. Therefore, even if the material for the metal pattern 130 is completely deposited on the substrate 10 provided with the refraction pattern 140 , the light-emitting display device according to the present disclosure may form the metal pattern 130 without a mask.

[0060] A capping layer structure 120 may be provided on the second electrode 115. The capping layer structure 120 may include first to third capping layers 121, 123, and 125 having different refractive indices. To this end, each of the capping layer structures 120 may include different materials, or may have different thicknesses even if they are made of the same material. In addition, the capping layer structure 120 may prevent the light-emitting element 110 from being degraded due to external moisture or oxygen. The light-emitting display device according to the present disclosure includes at least one first capping layer 121, and the metal pattern 130 and the refraction pattern 140 existing as the same layer are formed between the first capping layer 121 and the second capping layer 123, but the light-emitting display device according to the present disclosure is not limited thereto. In some cases, the light-emitting display device may include only a single first capping layer 121, or may include two, four, or more capping layers.

[0061] The first to third cover layers 121, 123, and 125 having different refractive indices may have a microcavity effect at interfaces with other components. Specifically, the first to third cover layers 121, 123, and 125 have a microcavity effect at the interface between the first cover layer 121 and the second electrode 115, the interface between the first cover layer 121 and the metal pattern 130, the interface between the first cover layer 121 and the refraction pattern 140, the interface between the second cover layer 123 and the metal pattern 130, the interface between the second cover layer 123 and the refraction pattern 140, and the interface between the second cover layer 123 and the third cover layer 125. In addition, the light-emitting display device according to the present disclosure can compensate the overall brightness of the first to third sub-pixels PXL1, PXL2, and PXL3 through the cover layer structure 120. In addition, the cover layer structure 120 having different refractive indices can refract light traveling toward the front surface to the side surface, thereby improving the brightness viewing angle and the color viewing angle.

[0062] Here, the first capping layer 121 disposed on the second electrode 115 is disposed between the second electrode 115 and the metal pattern 130, and improves the microcavity effect of the first subpixel PXL1 and the third subpixel PXL3. In addition, the first capping layer 121 may be used as an insulating film for forming the metal pattern 130 and the refraction pattern 140. As described above, the refraction pattern 140 according to the first embodiment has a low affinity for the conductive material, making it difficult to form the refraction pattern 140 directly on the surface of the second electrode 115, and thus the first capping layer 121 is disposed between the second electrode 115 and the refraction pattern 140 as an insulating film. For example, the first capping layer 121 may include an organic material, an inorganic material, or a mixture thereof. Here, the inorganic material may include silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy), etc., and the organic material may include photopropylene, polyimide, benzocyclobutene resin, acrylate, etc., but the present disclosure is not limited thereto. The first cover layer 121 may be a cover material having a predetermined refractive index to provide a microcavity effect and capable of covering the light emitting element 110 .

[0063] Meanwhile, an intermediate layer 113 between the first electrode 111 and the second electrode 115 may be provided on the embankment 150 and the first electrode 111 exposed by the embankment 150 in the entire display area. The intermediate layer 113 may refer to a single stacked organic layer consisting of a plurality of layers including a hole injection layer (HIL), a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL), and an electron injection layer (EIL). In addition, the intermediate layer 113 may include a light-emitting unit having a tandem structure including a plurality of stacks (a first stack and a second stack), each having a light-emitting layer (EML) and a charge generation layer (CGL) between the stacks. The tandem structure may have a plurality of stacks of two stacks or three or more stacks.

[0064] A bank 150 may be provided between the planarization layer 50 and the light emitting element 110. The bank 150 may cover a portion of an edge of the first electrode 111 and may expose a light emitting portion of the first electrode 111. Specifically, the bank 150 may cover a top surface and a side surface of an edge of the first electrode 111. In addition, the bank 150 may be provided over the entire surface of the display region and the non-display region except for the light emitting portion of the first electrode 111. For example, the bank 150 may be made of an organic material such as polyimide, acrylate, or benzocyclobutene-based resin.

[0065] Figure 2 is a graph showing a comparison of brightness and viewing angle between a light-emitting display device (A) including a refraction pattern 140 and a metal pattern 130 selectively provided for each sub-pixel and a light-emitting display device (B) not including the refraction pattern 140 and the metal pattern 130. In the graph, the horizontal axis represents a viewing angle (in degrees) of 0° based on the front surface, and the vertical axis represents brightness of 100% based on the brightness of the front surface.

[0066] In the light-emitting display device B in which the refraction pattern 140 and the metal pattern 130 are not provided, the brightness of the sub-pixels emitting light of different colors may be substantially the same. In this case, the brightness decreases from the front surface to the side surface, especially on the side with a viewing angle of 30°, where the brightness decreases sharply by 28.2% compared to 100% brightness of the front surface. In other words, the sub-pixels whose color gamut is far from white are sensitive to brightness changes depending on the viewing angle, which may cause a significant change in brightness of the entire sub-pixel toward the side surface.

[0067] In a light-emitting display device (A) in which a refraction pattern 140 and a metal pattern 130 are selectively set for each sub-pixel, the brightness of the sub-pixels may be different from each other. For example, the microcavity effects of the sub-pixels may be different. In this case, the sharp change in brightness toward the side surface can be minimized. In particular, when the side viewing angle reaches 30°, the brightness of the light-emitting display device (A) is reduced by 11.4% compared to 100% brightness of the front surface. Compared with the light-emitting display device (B) that does not include the refraction pattern 140 and the metal pattern 130, the light-emitting display device (A) including the refraction pattern 140 and the metal pattern 130 can reduce the brightness change by about 17% based on the side viewing angle of 30°. Therefore, the light-emitting display device according to the present disclosure includes a refraction pattern 140 in the sub-pixel that affects the brightness viewing angle, and includes a metal pattern 130 in other sub-pixels, thereby minimizing the brightness change depending on the viewing angle.

[0068] FIG. 3A to FIG. 3D It shows the manufacturing Figure 1 A cross-sectional view of a process of a light-emitting display device.

[0069] Reference Figure 3A , a planarization layer 50 may be formed on the substrate 10 to cover the thin film transistor TFT. Specifically, a buffer film 20 may be formed on the substrate 10 on which the light blocking layer 21 is formed, and an active layer 37 may be formed on the buffer film 20 by a mask process. Then, a gate insulating film 41 and a gate electrode 43 may be simultaneously formed on the buffer film 20 on which the active layer 37 is formed by a mask process. Then, an interlayer insulating film 30 having a source contact hole and a drain contact hole may be formed on the gate electrode 43 by a mask process. Then, a source electrode 51 / drain electrode 53 may be formed on the substrate 10 on which the interlayer insulating film 30 is formed by a mask process. Then, a passivation layer 40 and a planarization layer 50 having a contact hole 55 may be sequentially formed on the interlayer insulating film 30 on which the source electrode 51 / drain electrode 53 is formed by a mask process.

[0070] The first electrode 111 may be formed on the planarization layer 50 in each sub-pixel by a mask process. Then, the bank 150 may be formed on the planarization layer 50 by a mask process so that the bank 150 covers a portion of an edge of the first electrode 111. Then, the intermediate layer 113 and the second electrode 115 are sequentially formed over the entire surface of the substrate 10 on which the first electrode 111 and the bank 150 are formed to form the light emitting element 110.

[0071] Then, a first capping layer 121 may be formed over the second electrode 115 so that the first capping layer 121 covers the light emitting element 110. Here, the first capping layer 121 may include an organic material, an inorganic material, or a mixture thereof to facilitate subsequent deposition of the metal pattern 130 and the refraction pattern 140.

[0072] Reference Figure 3B , the refraction pattern 140 on the first cover layer 121 may be patterned into an area corresponding to the second sub-pixel PXL2. Preferably, but not necessarily, the refraction pattern 140 according to the first embodiment may be formed of an organic material having a low affinity for the material used for the metal pattern 130, so that the refraction pattern 140 is used as a mask for forming the metal pattern 130. For example, the refraction pattern 140 may include a polycyclic aromatic compound including organic molecules.

[0073] Reference Figure 3C , the metal pattern material 200 may be deposited over the entire surface of the substrate 10 on which the refraction pattern 140 is formed. The metal pattern material 200 reaches both the refraction pattern 140 and the first cap layer 121, but is not formed on the refraction pattern 140 due to a low probability of adhesion to the surface of the refraction pattern 140. That is, the metal pattern material 200 may not adhere to the surface of the refraction pattern 140. For example, in Figure 3C, the metal pattern material 200 that has reached the area corresponding to the first sub-pixel PXL1 and the third sub-pixel PXL3 on the first cover layer 121 is fixed to form the metal pattern 130, and the metal pattern material 200 that has reached the surface of the refraction pattern 140 is not fixed but separated. Even if the metal pattern material 200 is locally formed on the surface of the refraction pattern 140 according to a very low surface adhesion probability, by selecting the material according to the first embodiment to prevent the metal pattern material 200 from being uniformly formed on the surface of the refraction pattern 140, the second sub-pixel PXL2 provided with the refraction pattern 140 has almost no microcavity effect due to the locally formed metal pattern material 200. Therefore, the light-emitting display device according to the present disclosure includes the refraction pattern 140, so that the metal pattern 130 can be formed without a separate mask. Therefore, the metal pattern 130 of the light-emitting display device according to the present disclosure can be patterned at a more accurate position than when a mask is used, and the mask process can be omitted, which provides the effect of shortening the processing time and reducing the production energy.

[0074] Reference Figure 3D , on the substrate 10 on which the metal pattern 130 and the refraction pattern 140 are formed, a second capping layer 123 and a third capping layer 125 having different refractive indices may be sequentially formed on the entire surface.

[0075] Figure 4 is a cross-sectional view showing a light emitting display device according to a second embodiment of the present disclosure. Hereinafter, a description of the same configuration as that of the previous embodiment will be omitted or may be briefly provided.

[0076] Reference Figure 4 The light-emitting display device according to the second embodiment of the present disclosure includes a first cover layer 221, a second cover layer 223, and a third cover layer 225 on the light-emitting element 110, and a refraction pattern 240 and a metal pattern 230 between the first cover layer 221 and the second cover layer 223. Here, the refraction pattern 240 may be provided in a region corresponding to the second sub-pixel PXL2. The metal pattern 230 is provided with the same thickness in the first sub-pixel PXL1 and the third sub-pixel PXL3 without the refraction pattern 240, and may be thinner than the other sub-pixels PXL1 and PXL3 in the second sub-pixel PXL2.

[0077] The metal pattern 230 according to the second embodiment may include a first metal pattern 231 and a second metal pattern 232. The second metal pattern 232 may be disposed in the second sub-pixel PXL2 where the refraction pattern 240 is selectively disposed. In addition, the first metal pattern 231 may be disposed in the first sub-pixel PXL1 and the third sub-pixel PXL3 where the refraction pattern 240 is not disposed. The first metal pattern 231 and the second metal pattern 232 may not overlap each other.

[0078] The first metal pattern 231 may have a first thickness t1, and the second metal pattern 232 may have a second thickness t2 that is thinner than the first thickness t1. For example, the thickness of the metal pattern 230 corresponding to the second sub-pixel PXL2 may be thinner. In addition, the metal pattern 230 may be formed of a metal having a transmittance similar to that of the second electrode 115. Therefore, the second metal pattern 232 that is thinner than the first metal pattern 231 may transmit more light than the light it reflects. Therefore, in the light-emitting display device according to the present disclosure, by making the second metal pattern 232 of the second sub-pixel PXL2 thinner than the metal patterns of other sub-pixels, the microcavity effect may be selectively reduced. For example, the light-emitting display device according to the second embodiment has the effect of improving brightness and viewing angle.

[0079] The method of manufacturing the metal pattern 230 and the refraction pattern 240 according to the second embodiment may be the same as that of the first embodiment. For example, the manufacturing method according to the second embodiment may include forming the refraction pattern 240, and then depositing a material for the metal pattern 230 over the entire surface of the refraction pattern 240. However, the metal pattern 230 and the refraction pattern 240 according to the second embodiment may include a material different from the metal pattern 130 and the refraction pattern 140 according to the first embodiment. In other words, the light-emitting display device according to the second embodiment increases the probability of surface adhesion between the metal pattern 230 and the refraction pattern 240, thereby forming a second metal pattern 232 having a second thickness t2 thinner than the first thickness t1 on the refraction pattern 240. In the second embodiment, the first metal pattern 231 and the second metal pattern 232 of different thicknesses may be formed by the refraction pattern 240 without a separate mask.

[0080] Therefore, the light-emitting display device according to the present disclosure sets a refraction pattern in a sub-pixel that is sensitive to brightness changes depending on the viewing angle, and sets a metal pattern in other sub-pixels, thereby providing different microcavity effects in each sub-pixel. In addition, the light-emitting display device according to the present disclosure also includes a metal pattern on the selected refraction pattern, and the metal pattern on the refraction pattern is made thinner than the metal pattern in other sub-pixels, thereby providing different microcavity effects in each sub-pixel. Therefore, the light-emitting display device according to the present disclosure can cause a gradual change in brightness from the front surface to the side surface by providing a small microcavity effect in a sub-pixel that is sensitive to brightness changes depending on the viewing angle, thereby resulting in an effect of improving the brightness viewing angle. In addition, the light-emitting display device according to the present disclosure has the effect of improving the color viewing angle by improving the brightness viewing angle, because the brightness viewing angle is closely related to the color viewing angle.

[0081] In addition, the light-emitting display device according to the present disclosure may form a metal pattern without a mask by forming a refraction pattern with a specific material, thereby providing effects of shortening a processing time and reducing production energy.

[0082] At the same time, the light-emitting display device according to the present disclosure includes a cap layer with different refractive indexes in the cap layer structure provided on the front surface of the substrate, so that the light emitted from the light-emitting layer can be refracted to the side surface, thereby improving the brightness viewing angle and the color viewing angle. In addition, the light-emitting display device according to the present disclosure can provide a microcavity effect by adjusting the refractive index of the cap layer in the cap layer structure, thereby improving the luminous efficiency and achieving brightness compensation.

[0083] As is apparent from the foregoing, the light-emitting display device according to one or more aspects of the present disclosure has the following effects.

[0084] First, the light-emitting display device according to the present disclosure has a refraction pattern of an organic material in the second sub-pixel and a metal pattern of a metal material in the first sub-pixel and the third sub-pixel, thereby selectively reducing the microcavity effect of the second sub-pixel. Therefore, the light-emitting display device according to the present disclosure has the effect of reducing the rapid change of brightness depending on the viewing angle.

[0085] Second, the light-emitting display device according to the present disclosure may improve the brightness viewing angle through the refraction pattern and the metal pattern, thereby improving the color viewing angle based on the brightness viewing angle.

[0086] Third, the light-emitting display device according to the present disclosure includes a capping layer structure on a light-emitting element to protect the light-emitting element, and has an effect of improving a brightness viewing angle and a color viewing angle by refracting light emitted from the light-emitting element.

[0087] Fourth, the light-emitting display device according to the present disclosure uses a specific material for the refraction pattern to form a metal pattern without a separate mask, thereby providing the effect of shortening the processing time and reducing the production energy. Therefore, the light-emitting display device according to the present disclosure has an ESG (environment / social / governance) effect in terms of eco-friendliness, low power consumption, and process optimization.

[0088] According to one embodiment of the present disclosure, a light-emitting display device may include: a substrate including a first sub-pixel and a second sub-pixel; a light-emitting element on the substrate; a first cover layer on the second electrode of the light-emitting element; a metal pattern, which is arranged on the first cover layer and corresponds to the first sub-pixel; and a refraction pattern, which is arranged on the first cover layer and corresponds to the second sub-pixel.

[0089] In the light emitting display device according to one embodiment of the present disclosure, the refraction pattern may include an organic material.

[0090] In the light emitting display device according to one embodiment of the present disclosure, the refraction pattern may include a polycyclic aromatic compound.

[0091] In the light emitting display device according to one embodiment of the present disclosure, the metal pattern may include at least one of silver, aluminum, magnesium, and calcium.

[0092] In the light emitting display device according to one embodiment of the present disclosure, the second electrode and the metal pattern may include the same material.

[0093] In the light-emitting display device according to one embodiment of the present disclosure, the refraction pattern and the first cover layer may have different refractive indices.

[0094] In the light emitting display device according to one embodiment of the present disclosure, the metal pattern and the refraction pattern may be coplanar on the first cover layer and may be in contact with an upper surface of the first cover layer.

[0095] In the light emitting display device according to one embodiment of the present disclosure, the first cover layer may be an insulating film.

[0096] In the light emitting display device according to one embodiment of the present disclosure, the second sub-pixel may emit green light.

[0097] The light emitting display device according to one embodiment of the present disclosure may further include a second capping layer on the metal pattern and the refraction pattern.

[0098] The light-emitting display device according to one embodiment of the present disclosure may further include a third capping layer on the second capping layer and having a refractive index different from that of the second capping layer.

[0099] In the light emitting display device according to one embodiment of the present disclosure, the metal pattern may be further provided on the refraction pattern of the second sub-pixel.

[0100] In the light emitting display device according to one embodiment of the present disclosure, the metal pattern of the first sub-pixel may have a first thickness, and the metal pattern of the second sub-pixel may have a second thickness. The second thickness may be thinner than the first thickness.

[0101] In the light emitting display device according to one embodiment of the present disclosure, the second electrode may be a semi-transmissive and semi-reflective electrode.

[0102] According to one embodiment of the present disclosure, a method for manufacturing a light-emitting display device includes: forming a substrate including a first sub-pixel and a second sub-pixel; forming a light-emitting element on the substrate; forming a first cover layer on the second electrode of the light-emitting element; forming a refraction pattern on the first cover layer of the second sub-pixel; and forming a metal pattern on the first cover layer of the first sub-pixel.

[0103] In the method of manufacturing a light-emitting display device according to one embodiment of the present disclosure, the refraction pattern may be formed using an organic material having a low affinity for a metal pattern material.

[0104] In the method of manufacturing a light-emitting display device according to one embodiment of the present disclosure, a refraction pattern may be formed using a polycyclic aromatic compound.

[0105] In a method of manufacturing a light-emitting display device according to one embodiment of the present disclosure, forming a metal pattern includes depositing a metal pattern material over the entire surface of a substrate having a refraction pattern formed thereon, thereby forming a metal pattern in a region except for the refraction pattern.

[0106] In the method of manufacturing a light-emitting display device according to one embodiment of the present disclosure, a metal pattern may be formed without a separate mask.

[0107] It will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure is intended to cover such modifications and variations of the present disclosure as long as they fall within the scope of the appended claims and their equivalents.

Claims

1. A light-emitting display device, comprising: a substrate, the substrate comprising a first sub-pixel and a second sub-pixel; a light emitting element on the substrate; a first capping layer on the second electrode of the light-emitting element; a metal pattern, the metal pattern being on the first cover layer and corresponding to the first sub-pixel; as well as A refraction pattern is on the first cover layer and corresponds to the second sub-pixel.

2. The light-emitting display device according to claim 1, wherein: The refraction pattern includes an organic material.

3. The light-emitting display device according to claim 1, wherein: The refractive pattern includes a polycyclic aromatic compound.

4. The light-emitting display device according to claim 1, wherein: The metal pattern includes at least one of silver, aluminum, magnesium, and calcium.

5. The light-emitting display device according to claim 1, wherein: The second electrode and the metal pattern include the same material.

6. The light-emitting display device according to claim 1, wherein: The refraction pattern and the first capping layer have different refractive indices.

7. The light-emitting display device according to claim 1, wherein: The metal pattern and the refraction pattern are coplanar on the first capping layer and contact an upper surface of the first capping layer.

8. The light-emitting display device according to claim 7, wherein: The first cap layer is an insulating film.

9. The light-emitting display device according to claim 1, wherein: The second sub-pixel emits green light.

10. The light-emitting display device according to claim 1, further comprising: A second capping layer is provided on the metal pattern and the refraction pattern.

11. The light-emitting display device according to claim 10, further comprising: A third capping layer is on the second capping layer and has a refractive index different from that of the second capping layer.

12. The light-emitting display device according to claim 1, wherein: The metal pattern is also disposed on the refraction pattern of the second sub-pixel.

13. The light emitting display device according to claim 12, wherein: The metal pattern of the first sub-pixel has a first thickness, The metal pattern of the second sub-pixel has a second thickness, and The second thickness is thinner than the first thickness.

14. The light-emitting display device according to claim 1, wherein: The second electrode is a semi-transmissive and semi-reflective electrode.

15. A method for manufacturing a light-emitting display device, comprising: forming a substrate including a first sub-pixel and a second sub-pixel; forming a light-emitting element on the substrate; forming a first capping layer on the second electrode of the light emitting element; forming a refraction pattern on the first cover layer of the second sub-pixel; as well as A metal pattern is formed on the first capping layer of the first sub-pixel.

16. The method according to claim 15, wherein: The refraction pattern is formed using an organic material having a low affinity to the metal pattern material.

17. The method according to claim 15, wherein: The refraction pattern is formed using a polycyclic aromatic compound.

18. The method according to claim 16 or 17, wherein: Forming the metal pattern comprises: A metal pattern material is deposited over the entire surface of the substrate on which the refraction pattern is formed, thereby forming the metal pattern in a region except for the refraction pattern.

19. The method according to claim 18, wherein: The metal pattern is formed without a separate mask.

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