Organic light emitting display device

Abstract

In an organic light emitting display device with reduced color mixing, the organic light emitting display device includes a substrate; a plurality of pixel electrodes disposed on the substrate to be spaced apart from each other; a pixel defining layer disposed on the substrate and covering an edge of each of the plurality of pixel electrodes to expose a central portion of each of the plurality of pixel electrodes; and a plurality of spacers disposed on the pixel defining layer to be spaced apart from each other, wherein a distance between an edge of each of the plurality of spacers in a direction toward the closest pixel electrode and a portion of the closest pixel electrode not covered by the pixel defining layer is about 3 [mu] m or less.

Description

[0001] This application is a divisional application of the invention with the application date of December 9, 2020, application number 202011449241.6 and title "Organic Light-Emitting Display Device".

[0002] Cross-reference to related applications

[0003] This application claims the benefit of Korean Patent Application No. 10-2020-0007382, filed with the Korean Intellectual Property Office on January 20, 2020, the disclosure of which is incorporated herein by reference in its entirety. Technical field

[0004] The present inventive concept relates to an organic light-emitting display device, and more particularly, to an organic light-emitting display device in which color mixing is reduced. Background art

[0005] Generally, an organic light-emitting display device may have a structure in which an intermediate layer including an emission layer is disposed between a pixel electrode and a counter electrode. The intermediate layer may be formed by deposition and may include various layers. Among the layers included in the intermediate layer, a layer to be integrally formed is simultaneously formed in a plurality of pixels by using a mask called an aperture mask. For the emission layer, since a red emission layer is formed only in pixels emitting red light and a green emission layer is formed only in pixels emitting green light, the red emission layer and the green emission layer are formed only in specific pixels by using a fine metal mask. Summary of the invention

[0006] A problem with the above-described organic light-emitting display device is that materials for the emission layer formed in specific pixels in the manufacturing process are disposed adjacent to or at another pixel, and thus, when an image is formed after the display device is completed, color mixing may occur.

[0007] One or more embodiments include an organic light-emitting display device in which color mixing is reduced. However, the embodiments are exemplary and the scope of the present disclosure is not limited thereto.

[0008] Additional aspects will be set forth in part in the following description, and in part will be obvious from the description, or may be learned by practice of the embodiments presented in the present disclosure.

[0009] According to an exemplary embodiment of the present invention, an organic light emitting display device includes: a substrate; a plurality of pixel electrodes disposed on the substrate and spaced apart from each other; a counter electrode disposed on the plurality of pixel electrodes; a pixel defining layer disposed on the substrate and including a plurality of pixel defining holes exposing the plurality of pixel electrodes, each of the plurality of pixel defining holes exposing a central portion of a corresponding pixel electrode of the plurality of pixel electrodes; and a plurality of spacers disposed on the pixel defining layer and spaced apart from each other. Each of the plurality of spacers is disposed between the pixel defining layer and the counter electrode.

[0010] For each of the plurality of spacers, the distance between the edge of the closest pixel electrode and the portion of the closest pixel electrode not covered by the pixel defining layer is at most about 3 μm.

[0011] For each of the plurality of spacers, the distance between the edge of the closest pixel electrode and the portion of the closest pixel electrode not covered by the pixel defining layer is between about 1 μm and about 3 μm.

[0012] For each of the plurality of spacers, the distance between the edge of the closest pixel electrode and the portion of the closest pixel electrode not covered by the pixel defining layer is about 2 μm.

[0013] Each of the plurality of spacers is disposed between a corresponding pixel electrode of the plurality of pixel electrodes and the one of the pixel electrodes closest to the corresponding pixel electrode.

[0014] The plurality of pixel electrodes are disposed at intersections of a plurality of first virtual straight lines parallel to each other and a plurality of second virtual straight lines parallel to each other and intersecting the plurality of first virtual straight lines. The plurality of spacers include a plurality of first spacers disposed on the plurality of first virtual straight lines and a plurality of second spacers disposed on the plurality of second virtual straight lines. Each of the plurality of first spacers is disposed between two adjacent pixel electrodes among the plurality of pixel electrodes disposed on a corresponding first virtual straight line of the plurality of first virtual straight lines. Each of the plurality of second spacers is disposed between two adjacent pixel electrodes among the plurality of pixel electrodes disposed on a corresponding second virtual straight line of the plurality of second virtual straight lines.

[0015] A portion of the upper surface of the pixel defining layer between one pixel electrode among the plurality of pixel electrodes and one of the second closest pixel electrodes to the one pixel electrode contacts a hole injection layer or a hole transport layer.

[0016] Each of the plurality of pixel electrodes is surrounded by four of its closest spacers.

[0017] The organic light emitting display device further includes an auxiliary layer disposed on a side surface of each of the plurality of spacers, the auxiliary layer including the same material as the material of an emission layer disposed on a pixel electrode closest to the auxiliary layer.

[0018] The auxiliary layer is integrally formed with the emission layer.

[0019] The organic light-emitting display device further includes: a plurality of thin film transistors disposed on a substrate; and a planarization layer that covers the plurality of thin film transistors and has a plurality of through holes for exposing any one of a source electrode and a drain electrode of each of the plurality of thin film transistors. A plurality of pixel electrodes are disposed on the planarization layer. The plurality of pixel electrodes are electrically connected to the plurality of thin film transistors through the plurality of through holes, respectively. An emission layer disposed on one of the plurality of pixel electrodes is disposed on a portion of the one pixel electrode that contacts a corresponding one of the plurality of thin film transistors.

[0020] The organic light-emitting display device further includes a focusing lens that is disposed above one of the pixel electrodes and focuses light generated by the emission layer and traveling in a direction away from the pixel electrode.

[0021] The center of the focusing lens may match the center of the portion of one of the pixel electrodes that contacts a corresponding one of the plurality of thin film transistors.

[0022] According to an exemplary embodiment of the inventive concept, an organic light-emitting display device includes: a substrate; a pixel electrode disposed on the substrate; a pixel defining layer disposed on the substrate and including a pixel defining hole exposing the pixel electrode; a counter electrode disposed on the pixel electrode and the pixel defining layer; a pair of first spacers disposed on the pixel defining layer and spaced apart from each other in a first direction, the pixel defining hole being disposed between the pair of first spacers and each of the pair of first spacers being disposed between the pixel defining layer and the counter electrode; and a pair of second spacers disposed on the pixel defining layer and spaced apart from each other in a second direction different from the first direction, the pixel defining hole being disposed between the pair of second spacers and each of the pair of second spacers being disposed between the pixel defining layer and the counter electrode.

[0023] An edge of each of the pair of first spacers is spaced apart from a corresponding edge of the pixel electrode exposed by the pixel defining hole by a first distance. The first distance is measured in the first direction in a top view, and the first distance is between about 1 μm and about 3 μm.

[0024] An edge of each of the pair of second spacers is spaced apart from a corresponding edge of the pixel electrode exposed by the pixel defining hole by a second distance. The second distance is measured in the second direction in a top view, and the second distance is between about 1 μm and about 3 μm.

[0025] There is no spacer in a region adjacent to one of the pair of first spacers in the second direction and adjacent to one of the pair of second spacers in the first direction.

[0026] The organic light emitting display device further includes an emission layer disposed on the pixel electrode, and an auxiliary layer disposed on a side surface of each of the pair of first spacers, the auxiliary layer including the same material as that of the emission layer.

[0027] Other aspects, features, and advantages will become apparent and more readily understood from the following description of the embodiments, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and other aspects, features, and advantages of certain embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0029] Figure 1 A plan view schematically illustrating a part of an organic light emitting display device according to an exemplary embodiment of the inventive concept;

[0030] Figure 2 For an exemplary embodiment of the inventive concept along Figure 1 A schematic cross-sectional view taken along line II-II';

[0031] Figure 3 For an exemplary embodiment of the inventive concept along Figure 1 A schematic cross-sectional view taken along line III-III';

[0032] Figure 4 A schematic cross-sectional view of an operation of a manufacturing process of an organic light emitting display device according to a comparative example;

[0033] Figure 5 For an exemplary embodiment of the inventive concept Figure 1 A schematic cross-sectional view of an operation of a manufacturing process of an organic light emitting display device;

[0034] Figure 6 A schematic cross-sectional view of an organic light emitting display device according to an exemplary embodiment of the inventive concept; and

[0035] Figure 7 A schematic cross-sectional view of an organic light emitting display device according to an exemplary embodiment of the inventive concept. DETAILED DESCRIPTION

[0036] Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, these embodiments may have different forms and should not be construed as limited to the descriptions set forth herein. Accordingly, the embodiments are described only by way of example with reference to the figures to explain aspects of the description. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Throughout this disclosure, the expression "at least one of a, b, and c" indicates only a, only b, only c, both a and b, both a and c, both b and c, all of a, b, and c, or variations thereof.

[0037] Hereinafter, embodiments of the present disclosure will be described in detail by referring to the accompanying drawings. The same reference numerals in the drawings denote the same elements, and redundant explanations thereof are omitted.

[0038] It will be understood that when an element such as a layer, film, region, or plate is referred to as being "on" another element, it can be directly on the other element or intervening elements may be present therebetween. For ease of explanation, the dimensions of the elements in the drawings may be exaggerated. In other words, since the dimensions and thicknesses of the elements in the drawings are arbitrarily illustrated for ease of explanation, the following embodiments are not limited thereto.

[0039] In the following examples, the x-axis, y-axis, and z-axis are not limited to the three axes of a rectangular coordinate system and may be interpreted in a broader sense. For example, the x-axis, y-axis, and z-axis may be perpendicular to each other or may represent different directions that are not perpendicular to each other.

[0040] Figure 1 A plan view schematically illustrating a part of an organic light-emitting display device according to an exemplary embodiment of the inventive concept. Figure 2 For along Figure 1 A schematic cross-sectional view taken along line II-II'. Figure 3 For along Figure 1 A schematic cross-sectional view taken along line III-III'. In Figure 1 , each pixel is one of a red pixel R, a green pixel G, and a blue pixel B. In Figure 2 , a blue organic light-emitting device 310B and a red organic light-emitting device 310R are illustrated, and in Figure 3 , a green organic light-emitting device 310G and a red organic light-emitting device 310R are illustrated. Although Figure 2 illustrates a thin-film transistor 210, for the sake of simplicity of the drawings, Figure 3 the thin-film transistor 210 is not illustrated. Figure 2 The thin-film transistor 210 of Figure 2Only the driving thin film transistor 210 is illustrated, but other thin film transistors or capacitors, or wirings may be provided on the substrate 100. In Figure 3 others, other thin film transistors or capacitors, or wirings may be provided on the substrate 100.

[0041] The organic light emitting display device according to the present embodiment is provided with pixel electrodes 311R, 311G, and 311B, which are arranged on the substrate 100 and spaced apart from each other.

[0042] The substrate 100 may include glass, metal, or polymer resin. When the organic light emitting display device is flexible or bendable at a part, the substrate 100 may be flexible or bendable. In this case, the substrate 100 may include a polymer resin, for example, polyethersulfone, polyacrylate, polyetherimide, polyethylene naphthalate, polyethylene terephthalate, polyphenylene sulfide, polyarylate, polyimide, polycarbonate, or cellulose acetate propionate. The substrate 100 may have a multilayer structure including, for example, two layers, each layer including a polymer resin, and a barrier layer is provided between the two layers. In an exemplary embodiment, the barrier layer may include an inorganic material such as silicon oxide, silicon nitride, or silicon oxynitride. Various modifications may be made to the structure of the substrate 100.

[0043] Various components may be provided between the substrate 100 and the pixel electrodes 311R, 311G, and 311B. For example, as Figure 2 illustrated, the thin film transistor 210 may be provided on the substrate 100.

[0044] The thin film transistor 210 may include a semiconductor layer 211 (including amorphous silicon, polycrystalline silicon, or an organic semiconductor material), a gate electrode 213, a source electrode 215a, and a drain electrode 215b. The gate electrode 213 may include various conductive materials and have various layered structures. In an exemplary embodiment, the gate electrode 213 may include a Mo layer, an Al layer, or a combination thereof. The source electrode 215a and the drain electrode 215b may also include various conductive materials and various layered structures. In an exemplary embodiment, each of the source electrode 215a and the drain electrode 215b may include a Ti layer, an Al layer, or a combination thereof.

[0045] To ensure insulation between the semiconductor layer 211 and the gate electrode 213, a gate insulating film 121 may be disposed between the semiconductor layer 211 and the gate electrode 213. The gate insulating film 121 includes an inorganic material such as silicon oxide, silicon nitride, and / or silicon oxynitride. For convenience of description and simplicity of the drawings, the gate insulating film 121 is shown as not being included in the thin film transistor 210. The inventive concept is not limited thereto. For example, a part of the gate insulating film 121 disposed between the gate electrode 213 and the semiconductor layer 211 may be referred to as a component of the thin film transistor 210. Additionally, an interlayer insulating film 131 may be disposed on the gate electrode 213. The interlayer insulating film 131 includes an inorganic insulating material such as silicon oxide, silicon nitride, and / or silicon oxynitride. Source electrodes 215a and drain electrodes 215b may be disposed on the interlayer insulating film 131. The interlayer insulating film 131 including an inorganic insulating material may be formed by chemical vapor deposition (CVD) or atomic layer deposition (ALD). This applies to the embodiments described below and examples of their modifications.

[0046] A buffer layer 110 may be disposed between the thin film transistor 210 and the substrate 100. The buffer layer 110 includes an inorganic material such as silicon oxide, silicon nitride, and / or silicon oxynitride. The buffer layer 110 may be used to provide a planarized surface for subsequent processes such as forming the thin film transistor or to prevent or reduce the intrusion of impurities from the substrate 100 into the semiconductor layer 211 of the thin film transistor 210. In an exemplary embodiment, the buffer layer 110 may be disposed between the substrate 100 and the semiconductor layer 211 and between the substrate 100 and the gate insulating film 121.

[0047] A planarization layer 140 may be disposed on the thin film transistor 210. For example, as Figure 2 illustrated, before the organic light emitting device is disposed above the thin film transistor 210, the planarization layer 140 may approximately planarize the upper surface of the thin film transistor 210 or the upper surface of a protective film (not shown) covering the thin film transistor 210. For example, the planarization layer 140 may be used to provide a planarized surface for subsequent processes such as forming the organic light emitting device. The planarization layer 140 may include, for example, an organic material such as acrylic acid, benzocyclobutene (BCB), or hexamethyldisiloxane (HMDSO). Although Figure 2 and Figure 3 illustrate the planarization layer 140 as a single layer, various modifications (e.g., multi - layers) may be possible.

[0048] The organic light emitting display device may have an organic light emitting device in each pixel. Each organic light emitting device may include a pixel electrode, a counter electrode 315 (i.e., a common electrode), and an intermediate layer disposed therebetween. In an exemplary embodiment, the intermediate layer may include an emission layer. Figure 1 The pixel inFigure 1 In this case, each pixel may refer to a contact area between the pixel electrode and the intermediate layer. The contact area may be defined by an opening of the pixel defining layer 150, which will be described later.

[0049] The pixel electrodes 311R, 311G, and 311B may be disposed above the planarization layer 140 and may have a single-layer structure or a multi-layer structure. For the multi-layer structure, each pixel electrode may include a conductive layer such as indium tin oxide (ITO), indium zinc oxide (IZO), or indium oxide (In 2 O 3 ) and a conductive layer such as Al or Cu. The pixel electrodes 311R, 311G, and 311B may be in direct or indirect contact with any one of the source electrode 215a and the drain electrode 215b of the corresponding thin film transistor 210 through a through hole formed in the planarization layer 140.

[0050] The pixel defining layer 150 may be disposed on the planarization layer 140. The pixel defining layer 150 has an opening corresponding to each pixel, that is, an opening that at least exposes the central portion of each of the pixel electrodes 311R, 311G, and 311B, thereby defining the pixel. The parts indicated by Figure 1 R, G, and B in this case are respective parts of the pixel electrodes 311R, 311G, and 311B that are exposed and not covered by the pixel defining layer 150.

[0051] In addition, as illustrated in Figure 2 and Figure 3 , the pixel defining layer 150 may prevent arcing from occurring at the edges of the pixel electrodes 311R, 311G, and 311B by increasing the distance between the edge of each of the pixel electrodes 311R, 311G, and 311B and the counter electrode 315 above the pixel electrodes 311R, 311G, and 311B. The pixel defining layer 150 may include an organic material such as polyimide or hexamethyldisiloxane (HMDSO).

[0052] The intermediate layers 313R, 313G, and 313B of the organic light-emitting device may include low molecular weight materials or polymer materials. When the intermediate layers 313R, 313G, and 313B include low molecular weight materials, by using a vacuum deposition method, the intermediate layers 313R, 313G, and 313B may have 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), which are stacked in a single or composite structure. When the intermediate layers 313R, 313G, and 313B include polymer materials, the intermediate layers 313R, 313G, and 313B may have a structure including an HTL and an EML. In this case, the HTL may include PEDOT, and the EML may include polymer materials such as poly(phenylene vinylene) (PPV)-based materials and polyfluorene-based materials. The intermediate layers 313R, 313G, and 313B may be formed by a deposition method using a mask, and the EML may be formed by a deposition method or an inkjet printing method. The intermediate layers 313R, 313G, and 313B are not necessarily limited thereto, and may have various structures. The intermediate layers 313R, 313G, and 313B may include an integral layer over the pixel electrodes 311R, 311G, and 311B. The inventive concept is not limited thereto. In an embodiment, a layer (e.g., the EML) may be patterned such that the EML is separately disposed on the pixel electrodes 311R, 311G, and 311B of corresponding pixels. In the following description, for convenience, the reference numerals 313R, 313G, and 313B are used to refer to the EML.

[0053] The counter electrode 315 may be integrally formed with the red organic light-emitting device 310R, the green organic light-emitting device 310G, and the blue organic light-emitting device 310B to correspond to the pixel electrodes 311R, 311G, and 311B. The counter electrode 315 covers the display area and extends to an outer peripheral area outside the display area.

[0054] Since the organic light-emitting device may be easily damaged by external moisture or oxygen, a encapsulation layer (not shown) may cover and protect the organic light-emitting device. The encapsulation layer may cover the display area and extend to at least a part of the outer peripheral area. The encapsulation layer may include a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer.

[0055] A plurality of spacers 170 are spaced apart from each other on the pixel defining layer 150. In an exemplary embodiment, four spacers 170 are adjacent to each of the pixel electrodes 311R, 311G, and 311B. For example, the pixel electrode 311R is disposed between two pixel electrodes arranged in the y-axis direction and between two pixel electrodes arranged in the x-axis direction. In this state, each of the distances d1, d2, d3, and d4 between the edge of each of the spacers 170 in the direction toward the center of the closest pixel electrode and the portion of the closest pixel electrode not covered by the pixel defining layer 150 is about 3 μm or less. In an exemplary embodiment, the distances d1, d2, d3, and d4 may be, for example, the same distance of at most about 3 μm. The present invention is not limited thereto. The distances d1 and d2 measured along the x-axis direction may be different from the distances d3 and d4 measured along the y-axis direction. The spacer 170 may include an organic material (such as polyimide or hexamethyldisiloxane (HMDSO)) or an inorganic material (such as silicon oxide, silicon nitride, or silicon oxynitride). As described above, the counter electrode 315 formed integrally with the plurality of pixels may be disposed on the spacer 170. A layer of an intermediate layer formed integrally with the plurality of pixels, for example, HIL or HTL, is disposed on the spacer 170.

[0056] The EML may be deposited by using a mask 400 having deposition openings 410, as Figure 4 illustrated, where there is no spacer 170 between the mask 400 and the pixel defining layer 150. Figure 4 Illustrated is a case where the red EML is formed on the pixel electrode 311R in the red pixel. As Figure 4 illustrated, the red EML is deposited by using a mask 400 vertically spaced apart from the pixel defining layer 150. However, in this case, as Figure 4 indicated by the arrow 500 in, there may be a material for the red EML passing through the deposition opening 410 of the mask 400 and then traveling in the direction toward an adjacent pixel (for example, the pixel electrode 311G for green) rather than in the direction toward or around the pixel electrode 311R for red. Therefore, the material for the red EML may be disposed on or adjacent to the pixel electrode 311G for green. This may later result in that, after the organic light emitting display device is completed, the green pixel does not accurately emit only green light but also emits red light even slightly together with the green light.

[0057] As Figure 5 illustrated, in the organic light emitting display device according to the present embodiment, after the spacer 170 is provided between the mask 400 and the pixel defining layer 150, the EML will be deposited. By depositing the EML by using a mask 400 having deposition openings 410, the spacer 170 fills the gap between the mask 400 and the pixel defining layer 150. Figure 5Explain the formation of the red EML 313R on the pixel electrode 311R in the red pixel. As Figure 5 explained, when the mask 400 contacts the spacer 170, the red EML 313R is deposited. In this case, as Figure 5 indicated by the arrow 500 in, the material for the red EML passes through the deposition opening 410 of the mask 400 and then travels in a direction towards an adjacent pixel (e.g., the pixel electrode 311G for green), rather than towards the pixel electrode 311R for red or its surroundings. However, the material for the red EML 313R is blocked by the spacer 170 and is not allowed to travel in the direction towards the pixel electrode 311G for green. Therefore, in the organic light-emitting display device according to the present embodiment, light of precise expected color coordinates can be emitted from each of the red pixel R, the green pixel G, and the blue pixel B.

[0058] In each of the spacers 170, as the distance d1, d2, d3, or d4 between the edge in the direction towards the closest pixel electrode (i.e., the edge in the direction towards the center of the closest pixel electrode) and the portion of the closest pixel electrode not covered by the pixel defining layer 150 decreases as short as possible, when forming a specific EML, the material for the specific EML can be selectively deposited on the corresponding pixel electrode. Since an increase in the distance d1, d2, d3, or d4 means an increase in the area where the material for the specific EML is deposited when forming the specific EML, the material for the EML may even be deposited in an unnecessary area. In an exemplary embodiment, in each of the spacers 170, the distance d1, d2, d3, or d4 between the edge in the direction towards the center of the closest pixel electrode and the portion of the closest pixel electrode not covered by the pixel defining layer 150 is at most about 3 μm.

[0059] In each of the spacers 170, when the distance d1, d2, d3, or d4 between the edge in the direction toward the closest pixel electrode (i.e., the edge in the direction toward the center of the closest pixel electrode) and the portion of the closest pixel electrode not covered by the pixel defining layer 150 is excessively reduced, a part of the counter electrode 315 may be separated from another part of the counter electrode 315 in the process of forming the counter electrode 315. For example, in each of the spacers 170, when the distance d1, d2, d3, or d4 between the edge in the direction toward the center of the closest pixel electrode and the portion of the closest pixel electrode not covered by the pixel defining layer 150 is 0 μm, this means that the counter electrode 315 covers a step having an increased slope. The step has a height that is the sum of the height of the pixel defining layer 150 and the height of the spacer 170. As the slope of the step increases, the possibility that the counter electrode 315 may not be continuously formed to fill the space defined by the opening of the spacer 170 or the pixel defining layer 150 increases sharply when forming the counter electrode 315. For example, in the process of forming the counter electrode 315, when the slope of the step increases, a part of the counter electrode 315 may be separated from another part of the counter electrode 315, so that the focusing lens 190 (see Figure 6 ) may not be properly formed on the counter electrode 315.

[0060] To prevent such a problem, in each of the spacers 170, the distance d1, d2, d3, or d4 between the edge in the direction toward the closest pixel electrode (i.e., the edge in the direction toward the center of the closest pixel electrode) and the portion of the closest pixel electrode not covered by the pixel defining layer 150 is about 1 μm or greater. Therefore, when forming the counter electrode 315, in the process of forming the counter electrode 315, the small step corresponding to the height of the pixel defining layer 150 does not cause a part of the counter electrode 315 to be separated from another part of the counter electrode 315. In addition, in the portion from the pixel defining layer 150 to the spacer 170, in the process of forming the counter electrode 315, the height of the spacer 170 having a smaller step slope does not cause a part of the counter electrode 315 to be separated from another part thereof.

[0061] For this reason, in each of the spacers 170, the distance d1, d2, d3, or d4 between the edge in the direction toward the closest pixel electrode (i.e., the edge in the direction toward the center of the closest pixel electrode) and the portion of the closest pixel electrode not covered by the pixel defining layer 150 is a distance between about 1 μm and about 3 μm. In an exemplary embodiment, the distance d1, d2, d3, or d4 may be a distance of about 2 μm.

[0062] To ensure that in such as Figure 5The shielding effect of the spacer 170 in the EML deposition process illustrated in, each spacer 170 may have a suitable width w as illustrated in Figure 1 For example, as illustrated in Figure 1 The length of the edge (extending in the y-axis direction) of one of the spacers 170 adjacent to the pixel electrode 311B for blue can be defined as the width w of each of the spacers 170. The width w may be greater than or equal to the length of the edge (extending in the y-axis direction) of the pixel electrode 311B for blue closest to the spacer 170. The edge of the pixel electrode 311B for blue is defined by the exposed portion of the pixel electrode 311B for blue not covered by the pixel defining layer 150. For the convenience of description and the simplicity of the drawings, it is assumed that each of the spacers 170 is square. The inventive concept is not limited thereto. In an exemplary embodiment, each of the spacers 170 may be rectangular or any shape that can have a shielding effect in the EML deposition process.

[0063] Referring to Figure 5 , as described above, in the process of depositing the red EML 313R, the mask 400 contacts the spacer 170. However, as the area of the portion of the mask 400 contacting the spacer 170 increases, the possibility of damaging the mask 400 also increases. Therefore, the area of the portion of the mask 400 contacting the spacer 170 can be reduced as much as possible. To this end, as illustrated in Figure 1 the spacers 170 are spaced apart from each other. For example, the spacers 170 are not connected to each other on the pixel defining layer 150.

[0064] As described above, in the red EML 313R deposition process, the conveyance of the material for a specific EML in the direction toward an adjacent pixel electrode can be prevented or reduced by using the spacer 170. Therefore, each of the spacers 170 can be disposed between one pixel electrode and any one of the pixel electrodes closest to the one pixel electrode. For example, in Figure 1 for the green pixel G, the closest pixels can be two red pixels R disposed adjacent to each other in the Y-axis direction and two blue pixels B disposed adjacent to each other in the X-axis direction. Therefore, the spacers 170 are disposed between the pixel electrode 311G of the green pixel G and the pixel electrode 311B of the blue pixel B, and between the pixel electrode 311G of the green pixel G and the pixel electrode 311R of the red pixel R. For example, each of the plurality of pixel electrodes is surrounded by four spacers 170.

[0065] As in Figure 1As explained, multiple pixel electrodes may be disposed at intersections of a plurality of first virtual straight lines VL1 (extending in the X-axis direction) parallel to each other and a plurality of second virtual straight lines VL2 (extending in the Y-axis direction) parallel to each other and intersecting the first virtual straight lines VL1. The spacers 170 are disposed along the plurality of first virtual straight lines VL1 or the plurality of second virtual straight lines VL2 to correspond to positions between the multiple pixel electrodes. For example, the spacers 170 are disposed only on the plurality of first virtual straight lines VL1 or the plurality of second virtual straight lines VL2 to correspond to positions between the multiple pixel electrodes. In other words, the spacers 170 are not disposed between one pixel electrode among the multiple pixel electrodes and a pixel electrode adjacent to the one pixel electrode and closest to the one pixel electrode. In an exemplary embodiment, the multiple spacers 170 include a plurality of first spacers disposed on the plurality of first virtual straight lines VL1 and a plurality of second spacers disposed on the plurality of second virtual straight lines VL2. Each of the plurality of first spacers is disposed between two adjacent pixel electrodes of the multiple pixel electrodes (arranged on a corresponding first virtual straight line VL1 of the plurality of first virtual straight lines VL1). Each of the plurality of second spacers is disposed between two adjacent pixel electrodes of the multiple pixel electrodes (arranged on a corresponding second virtual straight line VL2 of the plurality of second virtual straight lines VL2). In an exemplary embodiment, there are no spacers in a region adjacent to the pair of first spacers along the second virtual straight line and adjacent to the pair of second spacers along the first virtual straight line.

[0066] For example, for a green pixel G, the closest pixels are two blue pixels B in the X-axis direction and two red pixels R in the Y-axis direction. The second-closest pixels to the green pixel G are four green pixels G. Each of the two spacers 170 arranged in the X-axis direction is disposed between the green pixel G and a corresponding one of the two blue pixels B arranged in the X-axis direction, and each of the two spacers 170 arranged in the Y-axis direction is disposed between the green pixel G and a corresponding one of the two red pixels R arranged in the Y-axis direction. No spacer is provided between the green pixel G and each of the four green pixels G. For a red pixel R, the closest pixels are four green pixels G arranged in the X-axis direction and the Y-axis direction, and the second-closest pixels to the red pixel G are four blue pixels B. Each of the two spacers 170 arranged in the X-axis direction is disposed between the red pixel R and a corresponding one of the two green pixels G arranged in the X-axis direction, and each of the two spacers 170 arranged in the Y-axis direction is disposed between the red pixel R and a corresponding one of the two green pixels G arranged in the Y-axis direction. No spacer is provided between the red pixel R and each of the four blue pixels B. For a blue pixel B, the closest pixels are four green pixels G arranged in the X-axis direction and the Y-axis direction, and the second-closest pixels to the blue pixel B are four red pixels R. Each of the two spacers 170 arranged in the X-axis direction is disposed between the blue pixel B and a corresponding one of the two green pixels G arranged in the X-axis direction, and each of the two spacers 170 arranged in the Y-axis direction is disposed between the blue pixel B and a corresponding one of the two green pixels G arranged in the Y-axis direction. No spacer is provided between the blue pixel B and each of the four red pixels R.

[0067] Since the above description applies to the case where the red pixels R, blue pixels B, and green pixels G are arranged as Figure 1 illustrated, when the arrangement method changes, the description of the positions of the spacers 170 may change accordingly. However, in any case, the spacers 170 are only provided on the plurality of first virtual lines VL1 or the plurality of second virtual lines VL2 corresponding to the positions between the plurality of pixel electrodes. Therefore, in the pixel electrodes 311R, 311G, and 311B, a portion of the upper surface of the pixel defining layer 150 between one pixel electrode and the pixel next to the pixel closest to the one pixel electrode contacts the HIL or HTL, and does not contact the spacer 170. This is because the spacer 170 does not exist in this portion. The portion of the spacer 170 on the upper surface of the pixel defining layer 150 may directly contact the spacer 170.

[0068] As Figure 5It is explained in [reference] that in the deposition process of depositing the red EML 313R, a part of the material for the red EML 313R that has passed through the deposition opening 410 of the mask 400 is blocked by the spacer 170 and is disposed on the side surface of the spacer 170. Therefore, in the organic light-emitting display device according to the present embodiment, the auxiliary layer 313R-A including the same material as the material of the red EML 313R provided on the closest pixel electrode (i.e., the pixel electrode 311R for red) can be disposed on the side surface of each of the spacers 170 in the direction towards the closest pixel electrode (i.e., the pixel electrode 311R for red). As Figure 5 It is explained in [reference] that the red EML 313R can be formed on the pixel electrode 311R for red, and thus, the auxiliary layer 313R-A including the same material as the material of the red EML 313R can be formed on the side surface of each of the spacers 170 in the direction towards the pixel electrode 311R for red. In addition, the auxiliary layer 313R-A can be integrally formed with the red EML 313R on the pixel electrode 311R for red. This applies to pixels that emit light of other colors (such as blue light and green light).

[0069] In Figure 1 [reference], each pixel is not square or rectangular, but has a shape with a chamfered corner. This is because, under the part of the pixel defining layer 150 that covers the chamfered corner, as Figure 2 It is explained in [reference] that the pixel electrodes 311B and 311R are in contact with their corresponding thin film transistors 210 through vias. In a higher-resolution display where the number of pixels per unit area increases, the pitch between pixels can be relatively reduced. Therefore, in the process of ensuring the contact area between the pixel electrodes 311B and 311R and their corresponding thin film transistors 210 through vias, as Figure 1 It is explained in [reference] that each pixel is not square or rectangular, but has a shape with a chamfered corner.

[0070] Figure 6 is a schematic cross-sectional view of an organic light-emitting display device according to an embodiment. Although for ease of explanation, Figure 6 the blue organic light-emitting device 310B for blue is illustrated, the present disclosure is not limited thereto. Referring to Figure 6 the description can be applied to the red organic light-emitting device 310R or the green organic light-emitting device 310G.

[0071] The difference between the organic light-emitting display device according to the present embodiment and the above-described organic light-emitting display device is that the portion of the pixel electrode 311B disposed on the planarization layer 140 that contacts either the source electrode 215a or the drain electrode 215b through a via hole is not covered by the pixel defining layer 150. For example, the portion of the pixel electrode 311B disposed on the planarization layer 140 that contacts either the source electrode 215a or the drain electrode 215b does not vertically overlap with the pixel defining layer 150. The EML 313B disposed on the pixel electrode 311B is disposed on the portion of the pixel electrode 311B that contacts the thin-film transistor 210. The EML 313B may be disposed on a portion other than the above-described portion of the pixel electrode 311B.

[0072] As described above, in a higher-resolution display in which the number of pixels per unit area increases, the pitch between pixels relatively decreases. Therefore, it may not be easy to ensure the contact area between the pixel electrode 311B and its corresponding thin-film transistor 210 through the via hole. To solve the above problem, as Figure 6 explained, the EML 313B disposed on the pixel electrode 311B may be disposed on the portion of the pixel electrode 311B that contacts the thin-film transistor 210.

[0073] In this case, since the EML 313B is even disposed on the inclined portion of the pixel electrode 311B. For example, the EML 313B is disposed on the inner surface of the via hole of the planarization layer 140, and the light emitted from this portion tends to travel in an inclined direction rather than in a direction approximately perpendicular to the substrate 100. As a result, since the light emitted from the EML 313B may be excessively diffused, the organic light-emitting display device according to the present embodiment may further include a focusing lens 190, as Figure 6 explained. The focusing lens 190 disposed above the pixel electrode 311B can prevent the excessive diffusion of the light emitted from the EML 313B by focusing the light generated from the EML 313B and traveling in a direction opposite to the direction toward the pixel electrode 311B.

[0074] The center of the focusing lens 190 may match the center of the portion of the pixel electrode 311B that contacts the thin-film transistor 210, for example, the center of the portion of the pixel electrode 311B that contacts the drain electrode 215b.

[0075] Although Figure 6 explains that the focusing lens 190 is disposed on the counter electrode 315, the present disclosure is not limited thereto. Figure 7 is a schematic cross-sectional view of an organic light-emitting display device according to an embodiment. As Figure 7As described, the encapsulation layer 180 may cover the blue organic light-emitting device 310B to protect the organic light-emitting device 310B, and the focusing lens 190 may be disposed on the encapsulation layer 180. The encapsulation layer 180 may cover the display area and extend to at least a part of the peripheral area. The encapsulation layer 180 may include a first inorganic encapsulation layer 181, an organic encapsulation layer 183, and a second inorganic encapsulation layer 185. The focusing lens 190 may be disposed on the second inorganic encapsulation layer 185. In an exemplary embodiment, a touch sensor layer for a touch screen function may be provided between the focusing lens 190 and the encapsulation layer 180.

[0076] According to the above-described embodiments configured as above, an organic light-emitting display device in which color mixing is reduced may be implemented. This effect does not limit the scope of the present invention.

[0077] It should be understood that the embodiments described herein should be considered only in a descriptive sense and not for purposes of limitation. The description of each feature or aspect in each embodiment should generally be considered available for other similar features or aspects in other embodiments. Although one or more embodiments have been described with reference to the accompanying drawings, those of ordinary skill in the art will understand that various changes may be made in form and detail without departing from the spirit and scope defined by the appended claims.

Claims

1. An organic light emitting display device, the organic light emitting display device comprising: a substrate; a plurality of thin film transistors disposed on the substrate; a planarization layer covering the plurality of thin film transistors and having a plurality of through holes for exposing a source electrode or a drain electrode of each of the plurality of thin film transistors; a plurality of pixel electrodes disposed on the planarization layer and spaced apart from each other, each of the plurality of pixel electrodes including a first portion connected to a corresponding one of the plurality of thin film transistors through a corresponding one of the plurality of through holes; a pixel defining layer disposed on the planarization layer and including a plurality of pixel defining holes exposing the plurality of pixel electrodes, wherein each of the plurality of pixel defining holes exposes a central portion and the first portion of a corresponding pixel electrode among the plurality of pixel electrodes; an intermediate layer disposed on a second portion of one of the plurality of pixel electrodes, the second portion including the first portion; and a focusing lens disposed above the one pixel electrode and focusing light generated by the intermediate layer and traveling in a direction away from the pixel electrode.

2. The organic light emitting display device according to claim 1, further comprising: a plurality of spacers disposed on the pixel defining layer and physically spaced apart from each other when viewed in a plan view, wherein a height of each of the plurality of spacers is less than a height of the pixel defining layer; and an auxiliary layer disposed on a side surface of each of the plurality of spacers in a direction toward a center of the closest pixel electrode, the auxiliary layer including a material same as a material of an emission layer disposed on the closest pixel electrode.

3. The organic light emitting display device according to claim 2, wherein a distance between an edge of each of the plurality of spacers adjacent to the closest pixel electrode and a portion of the closest pixel electrode not covered by the pixel defining layer is between 1 μm and 3 μm.

4. The organic light emitting display device as claimed in claim 2, wherein a distance between an edge of each of the plurality of spacers adjacent to the closest pixel electrode and a portion of the closest pixel electrode not covered by the pixel defining layer is 2 μm.

5. The organic light emitting display device as claimed in claim 2, wherein each of the plurality of spacers is disposed between a corresponding pixel electrode among the plurality of pixel electrodes and the one of the plurality of pixel electrodes closest to the corresponding pixel electrode.

6. The organic light emitting display device as claimed in claim 2, wherein the plurality of pixel electrodes are disposed at intersections of a plurality of first virtual straight lines parallel to each other and a plurality of second virtual straight lines parallel to each other and intersecting the plurality of first virtual straight lines, and wherein the plurality of spacers include a plurality of first spacers disposed on the plurality of first virtual straight lines and a plurality of second spacers disposed on the plurality of second virtual straight lines, Each of the plurality of first spacers is disposed between two adjacent pixel electrodes among the plurality of pixel electrodes that are arranged on a corresponding first virtual straight line among the plurality of first virtual straight lines. Each of the plurality of second spacers is disposed between two adjacent pixel electrodes among the plurality of pixel electrodes that are arranged on a corresponding second virtual straight line among the plurality of second virtual straight lines.

7. The organic light emitting display device according to claim 2, wherein each of the plurality of pixel electrodes is surrounded by four spacers closest to it.

8. The organic light emitting display device according to claim 2, wherein the auxiliary layer is integrally formed with the emission layer.

9. The organic light emitting display device according to claim 2, wherein when observed in the plan view, each pixel electrode among the plurality of pixel electrodes is surrounded by a corresponding plurality of the plurality of spacers, and wherein the corresponding plurality of spacers are physically spaced apart from each other.

10. The organic light emitting display device according to claim 2, wherein the plurality of spacers and the pixel defining layer are made of different materials.

11. The organic light emitting display device according to claim 10, wherein the plurality of spacers include an inorganic material.

12. The organic light emitting display device according to claim 1, wherein the center of the focusing lens matches the center of the first part of the one pixel electrode.

13. The organic light emitting display device according to claim 1, further comprising: a common electrode disposed above the intermediate layer corresponding to the plurality of pixel electrodes, wherein the focusing lens is disposed on the common electrode to directly contact the common electrode.

14. The organic light emitting display device according to claim 1, further comprising: a common electrode disposed above the intermediate layer corresponding to the plurality of pixel electrodes; and a encapsulation layer disposed above the common electrode, wherein the focusing lens is disposed on the encapsulation layer to directly contact the encapsulation layer.

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