Organic light-emitting display devices

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 arranged on the substrate to be spaced apart from each other; a pixel defining layer arranged 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 arranged 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 a nearest pixel electrode and a portion of the nearest pixel electrode not covered by the pixel defining layer is approximately 3 μm or less.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Korean Patent Application No. 10-2020-0007382 filed on January 20, 2020, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The 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

[0004] In general, 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 formed integrally is formed simultaneously in a plurality of pixels by using a mask called an opening mask. For the emission layer, since a red emission layer is formed only in a pixel emitting red light, and a green emission layer is formed only in a pixel emitting green light, a red emission layer and a green emission layer are formed only in a specific pixel by using a fine metal mask. Summary of the invention

[0005] The above-mentioned organic light emitting display device has a problem in that a material for an emission layer formed in a specific pixel in a manufacturing process is disposed adjacent to or at another pixel, and therefore, color mixing may occur when an image is formed after the display device is completed.

[0006] 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.

[0007] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the embodiments presented in the disclosure.

[0008] 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 to be 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 to be spaced apart from each other. Each of the plurality of spacers is disposed between the pixel defining layer and the counter electrode.

[0009] 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 at most about 3 μm.

[0010] 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 about 1 μm and about 3 μm.

[0011] 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 about 2 μm.

[0012] Each of the plurality of spacers is disposed between a corresponding pixel electrode of the plurality of pixel electrodes and one of the pixel electrodes that is closest to the corresponding pixel electrode.

[0013] A plurality of pixel electrodes are arranged at the intersection 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. A plurality of spacers include a plurality of first spacers arranged on the plurality of first virtual straight lines and a plurality of second spacers arranged on the plurality of second virtual straight lines. Each of the plurality of first spacers is arranged between two adjacent pixel electrodes arranged on a corresponding first virtual straight line of the plurality of first virtual straight lines among the plurality of pixel electrodes. Each of the plurality of second spacers is arranged between two adjacent pixel electrodes arranged on a corresponding second virtual straight line of the plurality of second virtual straight lines among the plurality of pixel electrodes.

[0014] A portion of the upper surface of the pixel defining layer between one of the plurality of pixel electrodes and one of the pixel electrodes that is second closest to the one pixel electrode contacts the hole injection layer or the hole transport layer.

[0015] Each of the plurality of pixel electrodes is surrounded by four spacers that are closest thereto.

[0016] 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 a same material as a material of an emission layer disposed on a pixel electrode closest to the auxiliary layer.

[0017] The auxiliary layer is formed integrally with the emission layer.

[0018] The organic light-emitting display device further includes: a plurality of thin film transistors arranged on the substrate; and a planarization layer, the planarization layer covering the plurality of thin film transistors and having a plurality of through holes for exposing any one of the source electrode and the drain electrode of each of the plurality of thin film transistors. A plurality of pixel electrodes are arranged 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. The emission layer arranged on one of the plurality of pixel electrodes is arranged on a portion of the pixel electrode that contacts a corresponding one of the plurality of thin film transistors.

[0019] The organic light emitting display device further includes a focusing lens that is disposed above one pixel electrode and focuses light that is generated by the emission layer and travels in a direction away from the pixel electrode.

[0020] The center of the focusing lens may match the center of the portion of one pixel electrode, the portion contacting a corresponding one of the plurality of thin film transistors.

[0021] According to an exemplary embodiment of the present invention, an organic light-emitting display device includes: a substrate; a pixel electrode disposed on the substrate; a pixel defining layer, the pixel defining layer being 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.

[0022] 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 a first direction in a top view and is between about 1 μm and about 3 μm.

[0023] 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 a second direction in a top view and is between about 1 μm and about 3 μm.

[0024] There is no spacer on 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.

[0025] 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 a material identical to that of the emission layer.

[0026] Other aspects, features and advantages will become apparent and more readily understood from the following description of the embodiments, the claims and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] 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:

[0028] Figure 1 A plan view schematically illustrating a portion of an organic light emitting display device according to an exemplary embodiment of the present inventive concept;

[0029] Figure 2 According to an exemplary embodiment of the present invention, Figure 1 A schematic cross-sectional view taken along line II-II';

[0030] Figure 3 According to an exemplary embodiment of the present invention, Figure 1 A schematic cross-sectional view taken along line III-III';

[0031] Figure 4 is a schematic cross-sectional view of an operation of a manufacturing process of an organic light emitting display device according to a comparative example;

[0032] Figure 5 According to an exemplary embodiment of the present invention Figure 1 A schematic cross-sectional view of an operation of a manufacturing process of an organic light emitting display device;

[0033] Figure 6 is a schematic cross-sectional view of an organic light emitting display device according to an exemplary embodiment of the present inventive concept; and

[0034] Figure 7 is a schematic cross-sectional view of an organic light emitting display device according to an exemplary embodiment of the inventive concept. DETAILED DESCRIPTION

[0035] Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein the same reference numerals refer to the same elements throughout. In this regard, the present embodiments may have different forms and should not be construed as being limited to the description set forth herein. Therefore, the embodiments are described below with reference to the figures only to explain aspects of the present description. As used herein, the term "and / or" includes any and all combinations of one or more related enumerated 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 a, b, and c, or variations thereof.

[0036] Hereinafter, the present disclosure will be described in detail by explaining embodiments of the present disclosure with reference to the accompanying drawings. The same reference numerals in the drawings represent the same elements, and redundant explanations thereof are omitted.

[0037] It will be understood that when a component, such as a layer, film, region, or plate, is referred to as being "on" another component, the component may be directly on the other component or there may be intervening components therebetween. For ease of explanation, the sizes of components in the drawings may be exaggerated. In other words, since the sizes and thicknesses of components in the drawings are arbitrarily illustrated for ease of explanation, the following embodiments are not limited thereto.

[0038] In the following examples, the x-axis, y-axis, and z-axis are not limited to the three axes of the rectangular coordinate system and can 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.

[0039] Figure 1 is a plan view schematically illustrating a portion of an organic light emitting display device according to an exemplary embodiment of the inventive concept. Figure 2 For along Figure 1 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'. Figure 1 In , each pixel is one of a red pixel R, a green pixel G, and a blue pixel B. Figure 2 In the embodiment, a blue organic light emitting device 310B and a red organic light emitting device 310R are explained, and in Figure 3 , a green organic light emitting device 310G and a red organic light emitting device 310R are explained. Figure 2 The thin film transistor 210 is illustrated, but 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 is a driving thin film transistor. Other thin film transistors or capacitors, or various wirings may be in each pixel. Although for the sake of convenience of explanation, 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. Figure 3 In the embodiment, other thin film transistors or capacitors, or wirings may be disposed on the substrate 100.

[0040] The organic light emitting display device according to the present embodiment is provided with pixel electrodes 311R, 311G, and 311B, which are arranged on a substrate 100 and spaced apart from each other.

[0041] The substrate 100 may include glass, metal or polymer resin. When the organic light emitting display device is flexible or bendable at a portion, 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, for example, a multilayer structure including two layers, each layer including a polymer resin, and a barrier layer disposed 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.

[0042] Various constituent elements may be provided between the substrate 100 and the pixel electrodes 311R, 311G, and 311B. Figure 2 As explained in FIG. 1 , the thin film transistor 210 may be disposed on the substrate 100 .

[0043] 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.

[0044] In order 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, and the gate insulating film 121 includes an inorganic material, such as silicon oxide, silicon nitride and / or silicon oxynitride. For the convenience of description and the simplicity of the drawings, the gate insulating film 121 is shown as not included in the thin film transistor 210. The inventive concept is not limited thereto. For example, a portion of the gate insulating film 121 disposed between the gate electrode 213 and the semiconductor layer 211 may be referred to as a constituent element of the thin film transistor 210. In addition, an interlayer insulating film 131 may be disposed on the gate electrode 213, and the interlayer insulating film 131 includes an inorganic insulating material, such as silicon oxide, silicon nitride and / or silicon oxynitride. The source electrode 215a and the drain electrode 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 their modified examples.

[0045] The buffer layer 110 may be disposed between the thin film transistor 210 and the substrate 100, and 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, for example, a subsequent process of forming a thin film transistor or to prevent or reduce impurities from invading the semiconductor layer 211 of the thin film transistor 210 from the substrate 100. 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.

[0046] The planarization layer 140 may be disposed on the thin film transistor 210. Figure 2 , 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 an 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 The planarization layer 140 is illustrated as a single layer, but various modifications (eg, multiple layers) may be possible.

[0047] 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 (ie, 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 in does not mean a pixel electrode, but a pixel means a region where the pixel electrode and the intermediate layer are in contact with each other. Figure 1 In the embodiment of the present invention, each pixel may refer to a contact region between a pixel electrode and an intermediate layer. The contact region may be defined by an opening of a pixel defining layer 150 to be described later.

[0048] 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, for example, 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 directly or indirectly contact any one of the source electrode 215a and the drain electrode 215b of the corresponding thin film transistor 210 through the through hole formed in the planarization layer 140.

[0049] 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 exposing at least a central portion of each of the pixel electrodes 311R, 311G, and 311B, thereby defining the pixel. Figure 1 The portions indicated by R, G, and B in are respective portions of the pixel electrodes 311R, 311G, and 311B, which are exposed and not covered by the pixel defining layer 150 .

[0050] In addition, if Figure 2 and Figure 3 , the pixel defining layer 150 can prevent arcing 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).

[0051] The intermediate layers 313R, 313G, and 313B of the organic light-emitting device may include a low molecular weight material or a polymer material. When the intermediate layers 313R, 313G, and 313B include a low molecular weight material, 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 structures stacked in a single or composite structure. When the intermediate layers 313R, 313G, and 313B include a polymer material, the intermediate layers 313R, 313G, and 313B may have a structure including HTL and EML. In this case, the HTL may include PEDOT, and the EML may include a polymer material, such as a polyphenylene vinylene (PPV)-based material and a polyfluorene-based material. The intermediate layer 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 layer 313R, 313G and 313B are not necessarily limited thereto, and may have various structures. The intermediate layer 313R, 313G and 313B may include an integral layer on the pixel electrodes 311R, 311G and 311B. The inventive concept is not limited thereto. In an embodiment, a layer (such as an EML) may be patterned so that the EML is separately disposed on the pixel electrodes 311R, 311G and 311B of the corresponding pixel. In the following description, for convenience, reference numerals 313R, 313G and 313B are used to refer to the EML.

[0052] The counter electrode 315 may be integrally formed with the red, green, and blue organic light emitting devices 310R, 310G, and 310B to correspond to the pixel electrodes 311R, 311G, and 311B. The counter electrode 315 covers the display area and extends to a peripheral area outside the display area.

[0053] Since the organic light-emitting device can be easily damaged by external moisture or oxygen, an encapsulation layer (not shown) can cover and protect the organic light-emitting device. The encapsulation layer can cover the display area and extend to at least a portion of the peripheral area. The encapsulation layer can include a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer.

[0054] 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 the same distance of, for example, up to 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 integrally formed with respect to a plurality of pixels may be disposed on the spacer 170. A layer of an intermediate layer integrally formed with a plurality of pixels, for example, a HIL or a HTL, is disposed on the spacer 170.

[0055] The EML may be deposited by using a mask 400 having a deposition opening 410, such as Figure 4 It is illustrated in FIG. 4 , in which no spacer 170 exists between the mask 400 and the pixel defining layer 150 . Figure 4 The case where the red EML is formed on the pixel electrode 311R in the red pixel is explained. Figure 4 , the red EML is deposited using a mask 400 vertically spaced apart from the pixel defining layer 150. However, in this case, Figure 4 5 indicates that there may be material for the red EML passing through the deposition opening 410 of the mask 400 and then traveling in a direction toward an adjacent pixel (e.g., the pixel electrode 311G for green) rather than toward the pixel electrode 311R for red or its surroundings. 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 emit exactly only green light, but emits red light together with green light even slightly.

[0056] like Figure 5 4, in the organic light emitting display device according to the present embodiment, after providing the spacer 170 between the mask 400 and the pixel defining layer 150, the EML is deposited. By depositing the EML using the mask 400 having the deposition opening 410, the spacer 170 fills the gap between the mask 400 and the pixel defining layer 150. Figure 5A case where a red EML 313R is formed on a pixel electrode 311R in a red pixel is explained. Figure 5 As explained in FIG. 4 , when the mask 400 contacts the spacer 170, the red EML 313R is deposited. Figure 5 500 in the figure indicates that the material for the red EML passes through the deposition opening 410 of the mask 400 and then moves in a direction toward an adjacent pixel (e.g., the pixel electrode 311G for green), rather than toward 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 move in a direction toward the pixel electrode 311G for green. Therefore, in the organic light emitting display device according to the present embodiment, light of precisely intended color coordinates can be emitted from each of the red pixel R, the green pixel G, and the blue pixel B.

[0057] In each of the spacers 170, as 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 reduced 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 the increase in the distance d1, d2, d3, or d4 means that the area where the material for the specific EML is deposited increases when forming the specific EML, the material for the EML can be deposited even 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 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 of at most about 3 μm.

[0058] 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 portion of the counter electrode 315 may be separated from another portion 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 with an increasing 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, when the counter electrode 315 is formed, the possibility that the counter electrode 315 may be discontinuously formed to fill the space defined by the opening of the spacer 170 or the pixel defining layer 150 increases sharply. For example, in the process of forming the counter electrode 315, when the slope of the step increases, a portion of the counter electrode 315 may be separated from another portion of the counter electrode 315, so that the focusing lens 190 (see Figure 6 ) may not be properly formed on the counter electrode 315.

[0059] In order 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 more. Therefore, when the counter electrode 315 is formed, in the process of forming the counter electrode 315, a small step corresponding to the height of the pixel defining layer 150 does not cause a portion of the counter electrode 315 to be separated from another portion 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 portion of the counter electrode 315 to be separated from another portion thereof.

[0060] As such, in each of the spacers 170, a distance d1, d2, d3, or d4 between an edge in a direction toward the closest pixel electrode (i.e., an edge in a direction toward the center of the closest pixel electrode) and a portion of the closest pixel electrode not covered by the pixel defining layer 150 is 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.

[0061] In order to ensure that Figure 5The shielding effect of the spacer 170 in the EML deposition process explained in Figure 1 The appropriate width w is explained in . For example, 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 that is not covered by the pixel defining layer 150. For the convenience of description and the simplicity of the accompanying drawings, it is assumed that each of the spacers 170 is a square. The inventive concept is not limited thereto. In an exemplary embodiment, each of the spacers 170 may be a rectangle or any shape that may have a shielding effect in the EML deposition process.

[0062] refer 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 may be reduced as much as possible. To this end, as shown in FIG. Figure 1 As explained in FIG. 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 .

[0063] As described above, in the red EML 313R deposition process, the material for a specific EML may be prevented from being transported in a direction toward an adjacent pixel electrode, or may be reduced by using the spacers 170. Therefore, each of the spacers 170 may be disposed between one pixel electrode and any one of the pixel electrodes closest to the one pixel electrode. Figure 1 , for the green pixel G, the closest pixels may 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 spacer 170 is 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.

[0064] like Figure 1, a plurality of pixel electrodes may be arranged at the intersection 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 line VL1. The spacer 170 is arranged along the plurality of first virtual straight lines VL1 or the plurality of second virtual straight lines VL2 to correspond to the position between the plurality of pixel electrodes. For example, the spacer 170 is arranged only on the plurality of first virtual straight lines VL1 or the plurality of second virtual straight lines VL2 to correspond to the position between the plurality of pixel electrodes. In other words, the spacer 170 is not arranged between one pixel electrode among the plurality of pixel electrodes and the pixel electrode next to the pixel electrode closest to the one pixel electrode. In an exemplary embodiment, the plurality of spacers 170 includes a plurality of first spacers arranged on the plurality of first virtual straight lines VL1 and a plurality of second spacers arranged on the plurality of second virtual straight lines VL2. Each of the plurality of first spacers is arranged between two adjacent pixel electrodes (arranged on the corresponding first virtual straight line VL1 of the plurality of first virtual straight lines VL1) of the plurality of pixel electrodes. Each of the plurality of second spacers is disposed between two adjacent pixel electrodes of the plurality of pixel electrodes (arranged on a corresponding second virtual straight line VL2 of the plurality of second virtual straight lines VL2). In an exemplary embodiment, no spacer exists on an area 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.

[0065] 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 pixels that are second closest 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 disposed 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 disposed in the X-axis direction and the Y-axis direction, and the pixels that are second closest to the red pixel G are four blue pixels G. 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 disposed between the red pixel R and each of the four blue pixels B. For the blue pixel B, the closest pixels are four green pixels G arranged in the X-axis direction and the Y-axis direction, and the pixels second closest to the blue pixel B are four red pixels R. Each of the two spacers 170 arranged in the X-axis direction is arranged 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 arranged 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.

[0066] Since the above description applies to Figure 1 The illustrated arrangement of red pixels R, blue pixels B, and green pixels G is described, so when the arrangement method changes, the description of the position of the spacer 170 may be changed accordingly. However, in any case, the spacer 170 is only arranged on a plurality of first virtual straight lines VL1 or a plurality of second virtual straight lines VL2 to correspond to the position between a plurality of pixel electrodes. Therefore, in the pixel electrodes 311R, 311G, and 311B, the portion of the upper surface of the pixel defining layer 150 between a pixel electrode and the pixel next to the pixel electrode closest to the pixel electrode contacts the HIL or HTL without contacting 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.

[0067] like Figure 5, in the deposition process of depositing the red EML 313R, a portion 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 to be 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 disposed on the closest pixel electrode (i.e., the pixel electrode 311R for red) may be disposed on the side surface of each of the spacers 170 in a direction toward the closest pixel electrode (i.e., the pixel electrode 311R for red). Figure 5 , the red EML 313R may be formed on the pixel electrode 311R for red, and therefore, an auxiliary layer 313R-A including the same material as that of the red EML 313R may be formed on the side surface of each of the spacers 170 in a direction toward the pixel electrode 311R for red. In addition, the auxiliary layer 313R-A may be formed integrally with the red EML 313R on the pixel electrode 311R for red. This is applicable to pixels emitting other color lights such as blue light and green light.

[0068] exist Figure 1 In the embodiment, each pixel is not a square or a rectangle, but has a shape with a chamfered corner. This is because, under the portion of the pixel defining layer 150 covering the chamfered corner, as shown in FIG. Figure 2 As explained in FIG. 1 , the pixel electrodes 311B and 311R contact the thin film transistors 210 corresponding thereto through the through holes. In a higher-resolution display in which 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 of ​​the pixel electrodes 311B and 311R contacting the thin film transistors 210 corresponding thereto through the through holes, as shown in FIG. Figure 1 As explained in , each pixel is not a square or rectangle, but has a shape with one chamfered corner.

[0069] 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 explained, but the present disclosure is not limited thereto. Figure 6 The description may be applied to the red organic light-emitting device 310R or the green organic light-emitting device 310G.

[0070] 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 a portion of the pixel electrode 311B disposed on the planarization layer 140 that contacts any one of the source electrode 215a and the drain electrode 215b through the through hole is not covered by the pixel defining layer 150. For example, a portion of the pixel electrode 311B disposed on the planarization layer 140 that contacts any one of the source electrode 215a and the drain electrode 215b does not vertically overlap the pixel defining layer 150. The EML 313B disposed on the pixel electrode 311B is disposed on a 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.

[0071] As described above, in a higher-resolution display in which the number of pixels per unit area increases, the pitch between pixels is relatively reduced. Therefore, it is not easy to ensure the contact area of ​​the pixel electrode 311B contacting the thin film transistor 210 corresponding thereto through the through hole. In order to solve the above problem, as Figure 6 As explained in FIG. 2 , the EML 313B disposed on the pixel electrode 311B may be disposed on a portion of the pixel electrode 311B contacting the thin film transistor 210 .

[0072] In this case, since the EML 313B is disposed even on the inclined portion of the pixel electrode 311B. For example, the EML 313B is disposed on the inner surface of the through hole of the planarization layer 140, 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 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, such as Figure 6 The focusing lens 190 disposed above the pixel electrode 311B may prevent excessive diffusion of light emitted from the EML 313B by focusing the light generated from the EML 313B and traveling in a direction opposite to a direction toward the pixel electrode 311B.

[0073] The center of the focusing lens 190 may match the center of a portion of the pixel electrode 311B contacting the thin film transistor 210 , for example, the center of a portion of the pixel electrode 311B contacting the drain electrode 215 b .

[0074] although Figure 6 It is illustrated that the focusing lens 190 is disposed on the opposing electrode 315 , but 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. Figure 7, 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 portion 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.

[0075] According to the above-described embodiment configured as above, an organic light emitting display device in which color mixing is reduced can be realized. This effect does not limit the scope of the present invention.

[0076] It should be understood that the embodiments described herein should be considered in a descriptive sense only and not for the purpose of limitation. The description of the features or aspects in each embodiment should generally be considered to be applicable to other similar features or aspects in other embodiments. Although one or more embodiments have been described with reference to the accompanying drawings, it will be understood by those of ordinary skill in the art that various changes can 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, comprising: 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 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 of a corresponding pixel electrode of the plurality of pixel electrodes; and a plurality of spacers disposed on the pixel defining layer to be physically spaced apart from each other when viewed in a plan view, wherein a height of each of the plurality of spacers is smaller than a height of the pixel defining layer, wherein the 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 at most 3 μm, and An auxiliary layer is 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 same material as a material of an emission layer disposed on the closest pixel electrode.

2. The organic light emitting display device according to claim 1, The distance between the 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.

3. The organic light emitting display device according to claim 1, The distance between the 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.

4. The organic light emitting display device according to claim 1, Each of the plurality of spacers is disposed between a corresponding pixel electrode of the plurality of pixel electrodes and one of the pixel electrodes that is closest to the corresponding pixel electrode.

5. The organic light emitting display device according to claim 1, wherein the plurality of pixel electrodes are arranged at intersections of a plurality of first virtual straight lines parallel to one another and a plurality of second virtual straight lines parallel to one another 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, wherein 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 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 that are arranged on a corresponding second virtual straight line of the plurality of second virtual straight lines.

6. The organic light emitting display device according to claim 1, A portion of the upper surface of the pixel defining layer between one pixel electrode among the plurality of pixel electrodes and a second pixel electrode closest to the one pixel electrode contacts the hole injection layer or the hole transport layer.

7. The organic light emitting display device according to claim 1, Each of the plurality of pixel electrodes is surrounded by four spacers that are closest thereto.

8. The organic light emitting display device according to claim 1, The auxiliary layer is formed integrally with the emission layer.

9. The organic light emitting display device according to claim 1, further comprising: A plurality of thin film transistors are disposed on the substrate; and a planarization layer covering the plurality of thin film transistors and having 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, wherein the plurality of pixel electrodes are arranged on the planarization layer, wherein the plurality of pixel electrodes are electrically connected to the plurality of thin film transistors through the plurality of through holes, and The emission layer provided in one pixel electrode among the plurality of pixel electrodes is provided on a portion of the pixel electrode contacting a corresponding one of the plurality of thin film transistors.

10. The organic light emitting display device according to claim 9, further comprising: A focusing lens is disposed above the one pixel electrode and focuses light generated by the emission layer and traveling in a direction away from the pixel electrode.

11. The organic light emitting display device according to claim 10, wherein the center of the focusing lens matches the center of the portion of the one pixel electrode, The portion contacts a corresponding one of the plurality of thin film transistors.

12. The organic light emitting display device according to claim 1, The plurality of spacers include an inorganic material.

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