Organic Light-Emitting Display Device and Method of Manufacturing the Same

Abstract

An organic light-emitting display device and a manufacturing method thereof are provided. The OLED device may include the following elements: a common electrode; a first pixel electrode stacked with the common electrode; a first emission layer disposed between the first pixel electrode and the common electrode; a second pixel electrode; a second emission layer disposed between the second pixel electrode and the common electrode; and a pixel defining layer including a first opening, a second opening, a first flat surface, and an uneven surface, wherein the first opening partially exposes the first pixel electrode, wherein the second opening partially exposes the second pixel electrode, wherein the first flat surface may be opposite to the uneven surface and may be disposed between the first pixel electrode and the second pixel electrode, and wherein the uneven surface may be disposed between the first opening and the second opening.

Description

[0001] The technical field relates to an organic light emitting display device and a method of manufacturing an organic light emitting display device. Background Art

[0002] An organic light emitting display (OLED) device is a self-emitting display device that uses an organic light emitting diode to emit light to display an image. The OLED device does not require a separate light source; thus, the thickness and weight of the OLED device can be minimized.

[0003] The OLED device may include a plurality of pixels. If charge undesirably flows from one pixel (of a certain color) to another pixel (of another color) during the operation of the OLED device, the image quality displayed by the OLED device may be unsatisfactory. Summary of the Invention

[0004] Embodiments may relate to an organic light emitting display (OLED) device in which lateral leakage current between pixels can be minimized.

[0005] Embodiments may relate to a method of manufacturing an OLED device.

[0006] The OLED device according to an embodiment may include the following elements: a substrate including a first pixel region, a second pixel region, a third pixel region, and a peripheral region surrounding the first pixel region to the third pixel region; a first pixel electrode, a second pixel electrode, and a third pixel electrode disposed on the substrate, the first pixel electrode, the second pixel electrode, and the third pixel electrode being respectively stacked with the first pixel region, the second pixel region, and the third pixel region; a pixel defining layer disposed on the substrate, the pixel defining layer being stacked with the peripheral region and having an upper surface with an uneven structure formed therebetween between the first pixel region and the second pixel region; a hole injection layer disposed on the first pixel electrode to the third pixel electrode and the pixel defining layer, the hole injection layer being formed along the contour of the upper surface of the pixel defining layer; a first emission layer, a second emission layer, and a third emission layer disposed on the hole injection layer, the first emission layer, the second emission layer, and the third emission layer being respectively stacked with the first pixel region, the second pixel region, and the third pixel region; and a common electrode disposed on the first emission layer to the third emission layer and the hole injection layer.

[0007] In an embodiment, the uneven structure may be formed only between the first pixel region and the second pixel region.

[0008] In an embodiment, the upper surface of the pixel defining layer between the first pixel region and the third pixel region may be flat.

[0009] In an embodiment, the distance between the first pixel region and the second pixel region may be less than the distance between the first pixel region and the third pixel region.

[0010] In an embodiment, the uneven structure may also be formed at an upper surface of the pixel defining layer between the first pixel region and the third pixel region.

[0011] In an embodiment, a portion of the upper surface of the pixel defining layer where the uneven structure is not formed may be flat.

[0012] In an embodiment, the second pixel region may be spaced apart from the first pixel region in a first direction, and the uneven structure may include recesses and protrusions alternately arranged along the first direction.

[0013] In an embodiment, each recess may extend in a second direction perpendicular to the first direction and parallel to the substrate.

[0014] In an embodiment, the lengths of the recesses may be consistent.

[0015] In an embodiment, the lengths of the recesses may increase as they are farther away from the first pixel region or the second pixel region.

[0016] In an embodiment, the OLED device may further include a spacer disposed between the pixel defining layer and the hole injection layer. The spacer overlaps with the peripheral region and does not overlap with the uneven structure.

[0017] In an embodiment, the first emission layer, the second emission layer, and the third emission layer may emit red light, green light, and blue light, respectively.

[0018] In an embodiment, the OLED device may further include a hole transport layer disposed between the hole injection layer and each of the first to third emission layers. The hole transport layer is formed along the contour of the upper surface of the pixel defining layer.

[0019] In an embodiment, the OLED device may further include an electron transport layer disposed between each of the first to third emission layers and the common electrode. The electron transport layer is formed along the contour of the upper surface of the pixel defining layer.

[0020] The OLED device according to an embodiment may include the following elements: a plurality of pixels, each including a pixel electrode, a hole injection layer, an emission layer, and a common electrode sequentially stacked; and a pixel defining layer that divides the plurality of pixels. The pixel defining layer has an upper surface at which an uneven structure is formed between the plurality of pixels. The hole injection layer may be commonly formed above the plurality of pixels and is formed along the contour of the upper surface of the pixel defining layer.

[0021] In an embodiment, a portion of the upper surface of the pixel defining layer where the uneven structure is not formed may be flat.

[0022] In an embodiment, the uneven structure may include recesses and protrusions alternately arranged between the plurality of pixels.

[0023] A method of manufacturing an OLED device according to an embodiment may include the steps of: forming a first pixel electrode, a second pixel electrode, and a third pixel electrode on a substrate, the first pixel electrode, the second pixel electrode, and the third pixel electrode being respectively superimposed on a first pixel region, a second pixel region, and a third pixel region; forming a pixel defining layer on the substrate, the pixel defining layer being superimposed on a peripheral region surrounding the first pixel region to the third pixel region and having an upper surface on which an uneven structure is formed between the first pixel region and the second pixel region; forming a hole injection layer on the first pixel electrode, the second pixel electrode, the third pixel electrode, and the pixel defining layer, the hole injection layer being formed along the contour of the upper surface of the pixel defining layer; forming a first emission layer, a second emission layer, and a third emission layer on the hole injection layer, the first emission layer, the second emission layer, and the third emission layer being respectively superimposed on the first pixel region, the second pixel region, and the third pixel region; and forming a common electrode on the first emission layer to the third emission layer and the hole injection layer.

[0024] In an embodiment, the second pixel region may be spaced apart from the first pixel region in a first direction, and the uneven structure may include recesses and protrusions alternately arranged along the first direction.

[0025] In an embodiment, the step of forming the pixel defining layer may include: forming an initial pixel defining layer on the substrate on which the first pixel electrode to the third pixel electrode are formed; disposing a halftone mask above the initial pixel defining layer; and exposing and developing the initial pixel defining layer using the halftone mask.

[0026] In an embodiment, the halftone mask may include a light-transmitting portion, a light-blocking portion, and a semi-transmissive portion. The light-transmitting portion may correspond to an opening portion of the pixel defining layer that partially exposes the first pixel electrode, the second pixel electrode, and the third pixel electrode, the light-blocking portion may correspond to the protrusion of the uneven structure, and the semi-transmissive portion may correspond to the recess of the uneven structure.

[0027] An embodiment may relate to an organic light emitting display (OLED) device. The OLED device may include the following elements: a substrate; a first pixel electrode, a second pixel electrode, and a third pixel electrode, all stacked on the substrate; a pixel defining layer including a first opening, a second opening, and a third opening that respectively expose portions of the first pixel electrode, the second pixel electrode, and the third pixel electrode, wherein the pixel defining layer may include a first uneven surface and a first flat surface, wherein the first uneven surface may be opposite to the first flat surface and may be disposed between the first opening and the second opening, and wherein the first flat surface may be disposed between the first pixel electrode and the second pixel electrode and may be disposed between the first uneven surface and the substrate; a first emission layer, a second emission layer, and a third emission layer corresponding to the first opening, the second opening, and the third opening respectively; and a common electrode stacked on each of the first emission layer, the second emission layer, and the third emission layer.

[0028] The first uneven surface may be disposed only between the first emission layer and the second emission layer.

[0029] The first uneven surface may be disposed between two relatively parallel surfaces of the first emission layer.

[0030] One surface of the pixel defining layer may be disposed not farther from the common electrode than any other surface of the pixel defining layer, the one surface of the pixel defining layer may be disposed between the first opening and the third opening, and may be flat.

[0031] The minimum distance between the first emission layer and the second emission layer may be less than the minimum distance between the first emission layer and the third emission layer.

[0032] The pixel defining layer may include a second uneven surface and a second flat surface. The second uneven surface may be disposed between the first opening and the third opening and may be opposite to the second flat surface. The second flat surface may be disposed between the first pixel electrode and the third pixel electrode and may be disposed between the second uneven surface and the substrate.

[0033] One surface of the pixel defining layer may be disposed not farther from the common electrode than any other surface of the pixel defining layer, the one surface of the pixel defining layer may be disposed between the second opening and the third opening, and may be flat.

[0034] The first uneven surface may include cavities and protrusions alternately arranged between the first opening and the second opening.

[0035] The length direction of each cavity may be parallel to the edge of the first opening and may be parallel to the substrate.

[0036] The lengths of the cavities may be equal.

[0037] The cavity may include a first cavity and a second cavity. The first cavity may be arranged closer to the first opening than the second cavity and may be shorter than the second cavity.

[0038] The OLED device may include the following elements: a hole injection layer that directly contacts each of the first pixel electrode, the second pixel electrode, the third pixel electrode, and the pixel defining layer; and a spacer disposed between the pixel defining layer and the hole injection layer and directly contacting the second flat surface of the pixel defining layer. The hole injection layer may include a cavity. The cavity may be disposed between the first opening and the second opening. The second flat surface of the pixel defining layer may extend from the edge of the second opening to the edge of the third opening and may be spaced apart from the first uneven surface.

[0039] The first emission layer, the second emission layer, and the third emission layer may be configured to emit red light, green light, and blue light, respectively. The first emission layer and the second emission layer may be adjacent to each other with no intermediate emission layer therebetween.

[0040] The OLED device may include the following elements: a hole injection layer that directly contacts each of the first pixel electrode, the second pixel electrode, the third pixel electrode, and the pixel defining layer; and a hole transport layer disposed between each of the first emission layer, the second emission layer, and the third emission layer and the hole injection layer. The hole transport layer may be stacked with the pixel defining layer and may include a cavity. The cavity may be disposed between the first opening and the second opening.

[0041] The OLED device may further include an electron transport layer disposed between each of the first emission layer, the second emission layer, and the third emission layer and the common electrode, and the electron transport layer is stacked with the pixel defining layer.

[0042] An embodiment may relate to an OLED device. The OLED device may include the following elements: a common electrode; a first pixel electrode stacked with the common electrode; a first emission layer disposed between the first pixel electrode and the common electrode; a second pixel electrode; a second emission layer disposed between the second pixel electrode and the common electrode; and a pixel defining layer including a first opening, a second opening, a first flat surface, and an uneven surface, wherein the first opening partially exposes the first pixel electrode, wherein the second opening partially exposes the second pixel electrode, wherein the first flat surface may be opposite to the uneven surface, may be disposed between the first pixel electrode and the second pixel electrode, and may extend from the first pixel electrode to the second pixel electrode, and wherein the uneven surface may be disposed between the first opening and the second opening.

[0043] The OLED device may further include the following elements: a third pixel electrode; and a third emission layer disposed between the third pixel electrode and the common electrode. The pixel defining layer may include a third opening, a second flat surface, and a third flat surface. The third opening may partially expose the third pixel electrode. The second flat surface may be opposite to the third flat surface, may be disposed between the second pixel electrode and the third pixel electrode, and may extend from the second pixel electrode to the third pixel electrode. The third flat surface may be disposed between the second opening and the third opening and may extend from the second opening to the third opening.

[0044] The uneven surface may include cavities and protrusions alternately arranged between the first opening and the second opening.

[0045] An embodiment may relate to a method of manufacturing an OLED device. The method may include the following steps: forming a first pixel electrode, a second pixel electrode, and a third pixel electrode on a substrate; forming a pixel defining layer on the substrate, wherein the pixel defining layer may include a first opening, a second opening, and a third opening that respectively partially expose the first pixel electrode, the second pixel electrode, and the third pixel electrode, wherein the pixel defining layer may include an uneven surface and a first flat surface, wherein the uneven surface may be opposite to the first flat surface and may be disposed between the first opening and the second opening, and wherein the first flat surface may be disposed between the first pixel electrode and the second pixel electrode and may be disposed between the uneven surface and the substrate; forming a first emission layer, a second emission layer, and a third emission layer, the first emission layer, the second emission layer, and the third emission layer corresponding to the first opening, the second opening, and the third opening respectively; and forming a common electrode that overlaps each of the first emission layer, the second emission layer, and the third emission layer.

[0046] The uneven surface may include cavities and protrusions alternately arranged between the first opening and the second opening.

[0047] Forming the pixel defining layer may include the following steps: forming a material layer on the substrate, the first pixel electrode, the second pixel electrode, and the third pixel electrode; disposing a halftone mask above the material layer; and using the halftone mask to expose and develop the material layer.

[0048] The halftone mask may include a light-transmitting portion, a light-blocking portion, and a semi-transmissive portion. The light-transmitting portion may correspond to the first opening, the second opening, and the third opening. The light-blocking portion may correspond to the protrusions of the uneven surface. The semi-transmissive portion may correspond to the cavities of the uneven surface.

[0049] The OLED device according to an embodiment may include a pixel defining layer having an uneven structure on an upper surface between pixels, and a hole injection layer may be formed on the pixel defining layer. Accordingly, a circuit path of the hole injection layer between pixels may be extended, and a lateral leakage current between pixels through the hole injection layer may be reduced.

[0050] In a method of manufacturing an OLED device according to an embodiment, a halftone mask may be used to form the pixel defining layer such that the pixel defining layer having an opening portion and an uneven upper surface may be formed through a single lithography process. Accordingly, a manufacturing time and / or cost of the OLED device may be minimized. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 is a plan view showing an organic light emitting display (OLED) device according to an embodiment.

[0052] Figure 2 is a cross-sectional view taken along line II-II' in Figure 1 according to an embodiment.

[0053] Figure 3 is a cross-sectional view showing the pixel defining layer and the hole injection layer in Figure 2 according to an embodiment.

[0054] Figure 4 is a plan view showing an OLED device according to an embodiment.

[0055] Figure 5 is a plan view showing an OLED device according to an embodiment.

[0056] Figure 6 is a cross-sectional view taken along line VI-VI' in Figure 5 according to an embodiment.

[0057] Figure 7 、 Figure 8 、 Figure 9 、 Figure 10 and Figure 11 are cross-sectional views showing structures formed in a method of manufacturing an OLED device according to an embodiment. DETAILED DESCRIPTION

[0058] Example embodiments will be described with reference to the accompanying drawings.

[0059] Although terms such as "first", "second", etc. may be used to describe various elements, these elements should not be limited by these terms. These terms can be used to distinguish one element from another. Without departing from the teachings of one or more embodiments, the first element may be named the second element. Describing an element as the "first" element does not require or imply the existence of a second element or other elements. Terms such as "first", "second", etc. can be used to distinguish different types or groups of elements. For the sake of brevity, terms such as "first", "second", etc. can respectively represent "first type (or first group)", "second type (or second group)", etc.

[0060] Figure 1 is a plan view showing an OLED device according to an embodiment. Figure 2 is according to an embodiment along Figure 1 a cross-sectional view taken along line II-II' in Figure 3 is a view showing according to an embodiment Figure 2 a cross-sectional view of the pixel defining layer and the hole injection layer in

[0061] Referring to Figure 1 、 Figure 2 and Figure 3 ,the OLED device may include a substrate 100, a plurality of pixel electrodes 201, 202, and 203, a pixel defining layer 300, a spacer 400, a hole injection layer 510, a hole transport layer 520, a plurality of emission layers 531, 532, and 533, an electron transport layer 540, and a common electrode 600. The OLED device may include a plurality of pixels PX1, PX2, and PX3 defined by the plurality of pixel electrodes 201, 202, and 203, the hole injection layer 510, the hole transport layer 520, the plurality of emission layers 531, 532, and 533, the electron transport layer 540, and the common electrode 600. The boundary of the pixel and / or the boundary of the pixel region associated with the pixel may correspond to the edge of the opening of the pixel defining layer 300.

[0062] The substrate 100 may be substantially formed of transparent glass containing SiO x The substrate 100 may be formed of a plastic material. Although not shown in the drawings, the substrate 100 may include at least one thin film transistor and / or capacitor for driving each pixel; the circuit for driving the pixel may use the thin film transistor, the capacitor, etc.

[0063] The substrate 100 may include a plurality of pixel regions PXA1, PXA2, and PXA3, and a peripheral region PPA. The pixel regions PXA1, PXA2, and PXA3 may include a plurality of first pixel regions PXA1, a plurality of second pixel regions PXA2, and a plurality of third pixel regions PXA3. The first pixel regions PXA1, the second pixel regions PXA2, and the third pixel regions PXA3 may be spaced apart from each other. For example, when the first pixel region PXA1 is spaced apart from the second pixel region PXA2 in a first direction DR1, the third pixel region PXA3 may be spaced apart from the second pixel region PXA2 in a second direction DR2 perpendicular to the first direction DR1. For example, when the first pixel region PXA1 is spaced apart from the second pixel region PXA2 in the second direction DR2, the third pixel region PXA3 may be spaced apart from the second pixel region PXA2 in the first direction DR1. In addition, the third pixel region PXA3 may be spaced apart from the first pixel region PXA1 in a third direction DR3 or in a fourth direction DR4 perpendicular to the third direction DR3. For example, the third direction DR3 may be inclined by approximately 45 degrees from the first direction DR1 in a clockwise direction, and the fourth direction DR4 may be inclined by approximately 45 degrees from the second direction DR2 in a clockwise direction. The boundaries of the pixel regions PXA1, PXA2, and PXA3 may respectively correspond to the (bottom) boundaries of the openings OP1, OP2, and OP3 of the pixel defining layer 300.

[0064] In an embodiment, the distance between the first pixel region PXA1 and the second pixel region PXA2 is less than the distance between the first pixel region PXA1 and the third pixel region PXA3. For example, the distance D12 between the first pixel region PXA1 and the second pixel region PXA2 may be approximately 19.2 μm, and the distance D13 between the first pixel region PXA1 and the third pixel region PXA3 may be approximately 25.9 μm. The peripheral region PPA may surround the pixel regions PXA1, PXA2, and PXA3.

[0065] The pixel electrodes 201, 202, and 203 may be disposed on the substrate 100. The pixel electrodes 201, 202, and 203 may include a first pixel electrode 201, a second pixel electrode 202, and a third pixel electrode 203. The first pixel electrode 201, the second pixel electrode 202, and the third pixel electrode 203 may respectively overlap with the first pixel region PXA1, the second pixel region PXA2, and the third pixel region PXA3. The first pixel electrode 201, the second pixel electrode 202, and the third pixel electrode 203 may include at least one of a reflective conductive material, a transparent conductive material, a translucent conductive material, etc.

[0066] The pixel defining layer 300 may be disposed on the substrate 100. The pixel defining layer 300 may include a plurality of opening portions OP1, OP2, and OP3 (or openings OP1, OP2, and OP3). The opening portions OP1, OP2, and OP3 may include a first opening portion OP1, a second opening portion OP2, and a third opening portion OP3. The first opening portion OP1, the second opening portion OP2, and the third opening portion OP3 may partially expose the first pixel electrode 201, the second pixel electrode 202, and the third pixel electrode 203, respectively. For example, the first opening portion OP1, the second opening portion OP2, and the third opening portion OP3 may cover the edge portions of the first pixel electrode 201, the second pixel electrode 202, and the third pixel electrode 203, respectively, and may expose the central portions of the first pixel electrode 201, the second pixel electrode 202, and the third pixel electrode 203, respectively. The pixel defining layer 300 may be superimposed on the peripheral region PPA. The opening portions OP1, OP2, and OP3 may define pixels PX1, PX2, and PX3, respectively. In other words, the pixel defining layer 300 may separate the pixels PX1, PX2, and PX3 from each other. The pixel defining layer 300 may include a photosensitive organic insulating material.

[0067] The pixels PX1, PX2, and PX3 may include a first pixel PX1, a second pixel PX2, and a third pixel PX3 that emit lights of different colors. In an embodiment, the first pixel PX1, the second pixel PX2, and the third pixel PX3 may be a red pixel that emits red light, a green pixel that emits green light, and a blue pixel that emits blue light, respectively. Each of the pixels PX1, PX2, and PX3 may include one of the pixel electrodes 201, 202, and 203, a part of the hole injection layer 510, a part of the hole transport layer 520, one of the emission layers 531, 532, and 533, a part of the electron transport layer 540, and a part of the common electrode 600.

[0068] The uneven structure 310 may be formed at the upper surface of the pixel defining layer 300. The uneven structure 310 may be formed between the pixels PX1, PX2, and PX3. In an embodiment, one or more uneven structures 310 may be formed between the first pixel region PXA1 and the other pixel regions PXA2 and PXA3. In other words, one or more uneven structures 310 may be formed between the first pixel region PXA1 and the second pixel region PXA2 and / or between the first pixel region PXA1 and the third pixel region PXA3. In another embodiment, the uneven structure 310 may also be formed between the second pixel region PXA2 and the third pixel region PXA3. The upper surface of the pixel defining layer 300 where the uneven structure 310 is not formed may be substantially flat (or planarized). The upper surface of the pixel defining layer 300 where the uneven structure 310 is not formed may be arranged not to be farther from the common electrode 600 than any other surface of the pixel defining layer 300.

[0069] In an embodiment, the uneven structure 310 may be formed only between the first pixel region PXA1 and the second pixel region PXA2, and no uneven structure 310 may be formed between the first pixel region PXA1 and the third pixel region PXA3. In such an embodiment, the upper surface of the pixel defining layer 300 located between the first pixel region PXA1 and the third pixel region PXA3 may be substantially flat (or planarized).

[0070] The uneven structure 310 may include a plurality of recesses 311 (or cavities 311) and a plurality of protrusions 312 (or projections 312). The recesses 311 may be recessed from the upper surface of the pixel defining layer 300 toward the substrate 100, and the protrusions 312 may protrude toward the common electrode 600. The recesses 311 and the protrusions 312 may be alternately arranged along the first direction DR1 or the second direction DR2 along which the second pixel region PXA2 and the first pixel region PXA1 are separated.

[0071] The uneven structure 310 may have a predetermined thickness TH. For example, the thickness TH of the uneven structure 310 may be about 1.4 μm. For example, the thickness TH of the uneven structure 310 may correspond to the depth of the recess 311 of the uneven structure 310. The uneven structure 310 may include uneven units periodically formed by alternately arranged recesses 311 and protrusions 312, and the uneven units may have a predetermined width WD. For example, the width WD of the uneven unit may be about 2.9 μm. For example, the width WD of the uneven unit may correspond to the sum of the widths of the recess 311 and the protrusion 312. Since the uneven structure 310 is formed at the upper surface of the pixel defining layer 300, the circuit path length of the pixel defining layer 300 along the upper surface defined by the recesses 311 and protrusions 312 of the uneven structure 310 can be increased.

[0072] Each recess 311 may extend along a direction perpendicular to the direction in which the recesses 311 and protrusions 312 are alternately arranged and parallel to the substrate 100. For example, when the recesses 311 and protrusions 312 are alternately arranged along the first direction DR1, each recess 311 may extend in the second direction DR2 and may be parallel to the nearest edge of the opening of the pixel defining layer 300; the length direction of the recess 311 may be the second direction DR2. In addition, when the recesses 311 and protrusions 312 are alternately arranged along the second direction DR2, each recess 311 may extend along the first direction DR1; the length direction of the recess 311 may be the first direction DR1.

[0073] In an embodiment, the lengths L1 of the recesses 311 may be substantially equal to each other. For example, the length L1 of the recess 311 may be the length in the length direction of the recess 311. The recesses 311 may have substantially the same length L1.

[0074] The spacer 400 may be disposed on the pixel defining layer 300. The spacer 400 may overlap with the peripheral area PPA. The spacer 400 may not overlap with the uneven structure 310. No spacer 400 may be formed between the first pixel region PXA1 and the other pixel regions PXA2 and PXA3. The spacer 400 may support the encapsulation substrate, the encapsulation layer, etc. formed above the pixels PX1, PX2, and PX3, and may separate the encapsulation substrate, the encapsulation layer, etc. from the pixels PX1, PX2, and PX3 to protect the pixels PX1, PX2, and PX3. The spacer 400 may include a photosensitive organic insulating material. In an embodiment, the spacer 400 may include a material substantially the same as the material of the pixel defining layer 300, and may be significantly wider than each recess 311, each protrusion 312, a plurality of recesses 311, and / or a plurality of protrusions 312 in the width direction of each recess 311 or each protrusion 312.

[0075] The hole injection layer 510 may be disposed on the first pixel electrode 201, the second pixel electrode 202, the third pixel electrode 203, the pixel defining layer 300, and the spacer 400. The hole injection layer 510 may be commonly formed above the first pixel PX1, the second pixel PX2, and the third pixel PX3. The hole injection layer 510 may be located above the entire upper surface of the substrate 100.

[0076] The hole injection layer 510 may be used to improve the injection of holes from each of the pixel electrodes 201, 202, and 203 to the hole transport layer 520. The hole injection layer 510 may include one or more phthalocyanine compounds such as copper phthalocyanine, polyaniline / dodecylbenzenesulfonic acid (PANI / DBSA), 4,4',4″-tris{N,-(2-naphthyl)-N-phenylamino}-triphenylamine (2TNATA), 4,4',4″-tris(3-methylphenylphenylamino)triphenylamine (m-MTDATA), 4,4',4″–tris(N,N-diphenylamino)triphenylamine (TDATA), polyaniline / camphorsulfonic acid (PANI / CSA), polyaniline / poly(4-styrenesulfonate) (PANI / PSS), N,N-diphenyl-N,N-bis-[4-(phenyl-m-tolyl-amino)-phenyl]-biphenyl-4,4'-diamine (DNTPD), and poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate) (PEDOT / PSS).

[0077] The hole injection layer 510 may be formed along the contours of the first pixel electrode 201, the second pixel electrode 202, the third pixel electrode 203, and the pixel defining layer 300 on the substrate 100. The hole injection layer 510 may be formed along the contour of the upper surface of the pixel defining layer 300. The hole injection layer 510 may be formed along the contour of the uneven structure 310 formed at the upper surface of the pixel defining layer 300 between the first pixel region PXA1 and the second pixel region PXA2. In addition, the hole injection layer 510 may be formed along the contour of the substantially flat (or planarized) upper surface of the pixel defining layer 300 between the first pixel region PXA1 and the third pixel region PXA3.

[0078] Since the hole injection layer 510 is formed between the first pixel region PXA1 and the second pixel region PXA2 along the contour of the upper surface of the pixel defining layer 300 where the uneven structure 310 is formed, the length of the hole injection layer 510 between the first pixel region PXA1 and the second pixel region PXA2 can be increased. For example, when the horizontal distance D12 between the first pixel region PXA1 and the second pixel region PXA2 is about 19.2 μm, in the comparative example, if the upper surface of the pixel defining layer 300 between the first pixel region PXA1 and the second pixel region PXA2 is substantially flat (or planarized), the length of the hole injection layer 510 between the first pixel region PXA1 and the second pixel region PXA2 can be about 21.5 μm. In the embodiment, the uneven structure 310 is formed at the upper surface of the pixel defining layer 300 located between the first pixel region PXA1 and the second pixel region PXA2, so that the length of the hole injection layer 510 between the first pixel region PXA1 and the second pixel region PXA2 can be about 28.0 μm. Therefore, when the uneven structure 310 is formed at the upper surface of the pixel defining layer 300, the length of the hole injection layer 510 can be increased by about 1.3 times.

[0079] The hole injection layer 510 can be formed of a material having a relatively high hole mobility. When the hole injection layer 510 is formed as a common layer over the pixels PX1, PX2, and PX3, the hole injection layer 510 can serve as a path for the movement of charges (holes) between the pixels PX1, PX2, and PX3. Therefore, when one pixel is driven, if the hole injection layer 510 provides a sufficiently short circuit path, the lateral leakage current can flow through the adjacent pixels via the hole injection layer 510. The hole injection layer 510 can be used as a conductive medium between the adjacent pixels PX1, PX2, and PX3, and the resistance R of the hole injection layer 510 serving as the conductive medium is shown in the following mathematical equation.

[0080] [Mathematical equation]

[0081]

[0082] ρ represents the resistivity of the hole injection layer 510, L represents the circuit path length of the hole injection layer 510, W represents the circuit path width of the hole injection layer 510, and t represents the circuit path thickness of the hole injection layer 510.

[0083] The first pixel PX1 that emits red light may have a relatively low turn-on voltage. When the circuit path between the first pixel region PXA1 and the second pixel region PXA2 is relatively short, according to the driving of the second pixel PX2, the first pixel PX1 may emit light in response to the lateral leakage current transmitted from the second pixel PX2 to the first pixel PX1 via the hole injection layer 510, and color mixing may occur at low brightness. According to an embodiment, the hole injection layer 510 may be formed between the first pixel region PXA1 and the second pixel region PXA2 along the upper surface of the pixel defining layer 300 where the uneven structure 310 is formed, so that the circuit path length L between the first pixel region PXA1 and the second pixel region PXA2 of the hole injection layer 510 can be increased; thus, the resistance R of the hole injection layer 510 between the first pixel region PXA1 and the second pixel region PXA2 can be increased. Therefore, the magnitude of the lateral leakage current between the first pixel PX1 and the second pixel PX2 via the hole injection layer 510 can be reduced, and color mixing at low brightness due to the lateral leakage current can be prevented.

[0084] The hole transport layer 520 may be disposed on the hole injection layer 510. The hole transport layer 520 may be commonly formed above the first pixel PX1, the second pixel PX2, and the third pixel PX3. The hole transport layer 520 may be located above the entire upper surface of the substrate 100.

[0085] The hole transport layer 520 may be used to smoothly transport the holes transmitted from the hole injection layer 510. The hole transport layer 520 may include one or more carbazole derivatives (such as at least one of N-phenylcarbazole, polyvinylcarbazole, etc.), fluorene derivatives, triphenylamine derivatives (such as N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1-biphenyl]-4,4'-diamine (TPD), 4,4',4″-tris(N-carbazolyl)triphenylamine (TCTA), etc.), N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine (NPB), and 4,4'-cyclohexylidene-bis[N,N-bis(4-methylphenyl)aniline] (TAPC). The hole injection layer 510 may include the same materials as those included in the hole transport layer 520 and may be doped with a P-type dopant for improving the hole injection characteristics by reducing the driving voltage of each pixel.

[0086] The hole transport layer 520 may be formed along the contour of the hole injection layer 510 disposed on the pixel defining layer 300. The hole transport layer 520 may be formed along the contour of the upper surface of the pixel defining layer 300. The hole transport layer 520 may be formed between the first pixel region PXA1 and the second pixel region PXA2 along the contour of the uneven structure 310 formed at the upper surface of the pixel defining layer 300. In addition, the hole transport layer 520 may be formed between the first pixel region PXA1 and the third pixel region PXA3 along the contour of the substantially flat (or planarized) upper surface of the pixel defining layer 300. Since the hole transport layer 520 is formed between the first pixel region PXA1 and the second pixel region PXA2 along the contour of the upper surface of the pixel defining layer 300 where the uneven structure 310 is formed, the length of the hole transport layer 520 between the first pixel region PXA1 and the second pixel region PXA2 can be increased.

[0087] The emission layers 531, 532, and 533 may be formed on the hole transport layer 520. The emission layers 531, 532, and 533 may include a first emission layer 531, a second emission layer 532, and a third emission layer 533. The first emission layer 531, the second emission layer 532, and the third emission layer 533 may be respectively stacked with the first pixel region PXA1, the second pixel region PXA2, and the third pixel region PXA3. The first emission layer 531, the second emission layer 532, and the third emission layer 533 may include a host and a dopant. The first emission layer 531, the second emission layer 532, and the third emission layer 533 may include materials that respectively emit red light, green light, and blue light, and may be formed of a phosphorescent material or a fluorescent material.

[0088] The first emission layer 531 that emits red light may include a host material containing CBP (carbazole biphenyl) or mCP (1,3-bis(carbazol-9-yl)benzene), and may be formed of a phosphorescent material including a dopant, wherein the dopant includes at least one selected from PIQIr(acac) (bis(1-phenylisoquinoline)acetylacetonate iridium), PQIr(acac) (bis(1-phenylquinoline)acetylacetonate iridium), PQIr(tris(1-phenylquinoline)iridium), and PtOEP (platinum octaethylporphyrin), or the first emission layer 531 that emits red light may be formed of a fluorescent material including PBD:Eu(DBM) 3 (Phen) or perylene.

[0089] The second emission layer 532 that emits green light may include a host material containing CBP or mCP, and may be formed of a phosphorescent material including a dopant material containing Ir(ppy) 3 (fac-tris(2-phenylpyridine)iridium), or may be formed of a material including Alq 3Formation of a fluorescent material of tris(8-hydroxyquinoline) aluminum

[0090] The third emission layer 533 that emits blue light may include a host material containing CBP or mCP, and may be formed of a phosphorescent material including a dopant material containing (4,6-F 2 ppy) 2 Irpic, or may be formed of a fluorescent material including at least one selected from the group consisting of spiro-DPVBi, spiro-6P, divinylbenzene (DSB), divinylarylide (DSA), PFO-based polymers, and PPV-based polymers.

[0091] The electron transport layer 540 may be disposed on the first emission layer 531, the second emission layer 532, the third emission layer 533, and the hole transport layer 520. The electron transport layer 540 may be commonly formed above the first pixel PX1, the second pixel PX2, and the third pixel PX3. The electron transport layer 540 may be located above the entire upper surface of the substrate 100.

[0092] The electron transport layer 540 may transfer electrons from the common electrode 600 to the first emission layer 531, the second emission layer 532, and the third emission layer 533. In addition, the electron transport layer 540 may prevent or reduce the case where holes injected from the first pixel electrode 201, the second pixel electrode 202, and the third pixel electrode 203 move to the common electrode 600 via the first emission layer 531, the second emission layer 532, and the third emission layer 533. That is, the electron transport layer 540 may serve as a hole blocking layer, and may help holes and electrons to combine in the first emission layer 531, the second emission layer 532, and the third emission layer 533.

[0093] The electron transport layer 540 may include, for example, tris(8-hydroxyquinoline) aluminum (Alq 3 ), 1,3,5-tris(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene (TPBi), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), 3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ), 4-(naphthalen-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ), 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (tBu-PBD), bis(2-methyl-8-hydroxyquinolinato-N1,O8)-(1,1'-biphenyl-4-ol) aluminum (BAlq), bis(benzoquinolin-10-hydroxy) beryllium (Bebq 2 ), 9,10-di(naphthalen-2-yl)anthracene (ADN), and mixtures thereof.

[0094] The OLED device may further include an electron injection layer (not shown) disposed on the electron transport layer 540. The electron injection layer can be used to improve the injection of electrons from the common electrode 600 to the electron transport layer 540. When the OLED device includes the electron transport layer 540 and the electron injection layer, the electron transport layer 540 may be formed of at least one of LiF, LiQ, Li 2 O, BaO, NaCl, CsF, and lanthanide metals such as Yb, or a metal halide such as RbCl and / or RbI. In addition, the electron injection layer may be formed of a material in which an electron transport material is mixed with an insulating organic metal salt. The energy band gap of the organic metal salt may be about 4 eV or greater. For example, the organic metal salt may include a metal acetate, a metal benzoate, a metal acetoacetate, a metal acetylacetonate, or a metal stearate.

[0095] The electron transport layer 540 may be formed along the contours of the first emission layer 531, the second emission layer 532, the third emission layer 533, and the hole transport layer 520 disposed on the pixel defining layer 300. The electron transport layer 540 may be formed along the contour of the upper surface of the pixel defining layer 300. The electron transport layer 540 may be formed along the contour of the uneven structure 310 formed at the upper surface of the pixel defining layer 300 between the first pixel region PXA1 and the second pixel region PXA2. In addition, the electron transport layer 540 may be formed along the contour of the substantially flat (or planarized) upper surface of the pixel defining layer 300 between the first pixel region PXA1 and the third pixel region PXA3. Since the electron transport layer 540 is formed along the contour of the upper surface of the pixel defining layer 300 where the uneven structure 310 is formed between the first pixel region PXA1 and the second pixel region PXA2, the length of the electron transport layer 540 between the first pixel region PXA1 and the second pixel region PXA2 can be increased.

[0096] The common electrode 600 may be disposed on the electron transport layer 540. The common electrode 600 may be commonly formed above the first pixel PX1, the second pixel PX2, and the third pixel PX3. The common electrode 600 may be located above the entire upper surface of the substrate 100. The common electrode 600 may include at least one of a reflective conductive material, a transparent conductive material, and a semi-transparent conductive material.

[0097] When the OLED device is a bottom emission type in which an image can be displayed toward the substrate 100, each of the first pixel electrode 201, the second pixel electrode 202, and the third pixel electrode 203 may be a transparent electrode, and the common electrode 600 may be a reflective electrode. The first pixel electrode 201, the second pixel electrode 202, and the third pixel electrode 203 may be made of ITO, IZO, ZnO, and In 2 O with a high work function3 The common electrode 600 may be formed of at least one of metals having a low work function such as at least one of Ag, Mg, Al, Pt, Au, Ni, Nd, Ir, Cr, Li, and Ca.

[0098] When the OLED device is a top-emission type in which an image can be displayed toward the common electrode 600, each of the first pixel electrode 201, the second pixel electrode 202, and the third pixel electrode 203 may be a reflective electrode, and the common electrode 600 may be a transparent electrode. The first pixel electrode 201, the second pixel electrode 202, and the third pixel electrode 203 may include a reflective layer including at least one of Ag, Mg, Al, Pt, Au, Ni, Nd, Ir, Cr, Li, Ca, and mixtures thereof, and the common electrode 600 may include ITO, IZO, ZnO, and In 2 O 3 a transmissive layer of at least one of them.

[0099] Figure 4 is a plan view showing an organic light-emitting display device according to an embodiment.

[0100] Except for the shape and size of the uneven structure, the OLED device described with reference to Figure 4 may be substantially the same as or similar to the OLED device described with reference to Figures 1 to 3 Therefore, the description of the above elements may not be repeated.

[0101] With reference to Figure 4 , the length L2 of the recess 311 of the uneven structure 310 formed on the upper surface of the pixel defining layer 300 may increase as it moves away from the first pixel region PXA1 or the second pixel region PXA2. For example, the length L2 of the recess 311 may be the length in the length direction of the recess 311. For example, the length L2 of the recess 311 may increase sequentially from the first pixel region PXA1 to the midpoint between the first pixel region PXA1 and the second pixel region PXA2 along the first direction DR1 or the second direction DR2, and may decrease sequentially from the midpoint to the second pixel region PXA2 along the first direction DR1 or the second direction DR2. The length L2 of the recess 311 may decrease as it approaches the first pixel region PXA1 or the second pixel region PXA2, and may increase as it moves away from the first pixel region PXA1 or the second pixel region PXA2.

[0102] When the uneven structure 310 is formed between the first pixel region PXA1 and the second pixel region PXA2, a leakage current path bypassing the uneven structure 310 may be formed between the first pixel region PXA1 and the second pixel region PXA2. However, when the length L2 of the recess 311 increases as it moves away from the first pixel region PXA1 or the second pixel region PXA2, the length of the leakage current path bypassing the uneven structure 310 can be increased. Therefore, the magnitude of the lateral leakage current between the first pixel PX1 and the second pixel PX2 can be reduced, or the generation of the lateral leakage current can be substantially prevented.

[0103] Figure 5 is a plan view showing an organic light emitting display device according to an embodiment. Figure 6 is according to an embodiment along Figure 5 a cross-sectional view taken along line VI-VI' in

[0104] Except for the position where the uneven structure is formed, referring to Figure 5 and Figure 6 the OLED device described can be substantially the same as or similar to the OLED device described with reference to Figures 1 to 3 Therefore, the description of the above elements may not be repeated.

[0105] Referring to Figure 5 and Figure 6 In addition to being formed between the first pixel region PXA1 and the second pixel region PXA2, the uneven structures 310 and 320 formed on the upper surface of the pixel defining layer 300 may also be formed between the first pixel region PXA1 and the third pixel region PXA3. The uneven structures 310 and 320 may include a first uneven structure 310 formed between the first pixel region PXA1 and the second pixel region PXA2, and may include a second uneven structure 320 formed between the first pixel region PXA1 and the third pixel region PXA3. The upper surface of the pixel defining layer 300 where the uneven structures 310 and 320 are not formed may be substantially flat (or planarized).

[0106] The second uneven structure 320 may include a plurality of recesses 321 and a plurality of protrusions 322. The recesses 321 and the protrusions 322 may be alternately arranged along a third direction DR3 or a fourth direction DR4 in which the third pixel region PXA3 and the first pixel region PXA1 are spaced apart.

[0107] The recess 321 can extend along a direction perpendicular to the direction along which the recesses 321 and the protrusions 322 are alternately arranged, parallel to the nearest edge of the opening of the pixel defining layer 300, and parallel to the substrate 100. For example, when the recesses 321 and the protrusions 322 are alternately arranged along the third direction DR3, each recess 321 can extend in the fourth direction DR4. In addition, when the recesses 321 and the protrusions 322 are alternately arranged along the fourth direction DR4, each recess 321 can extend in the third direction DR3.

[0108] In an embodiment, the lengths L3 of the recesses 321 can be substantially equal. For example, the length L3 of the recess 321 can be the length in the length direction of the recess 321. The recesses 321 can have substantially the same length L3.

[0109] In another embodiment, the length L3 of the recess 321 can increase as it moves away from the first pixel region PXA1 or the third pixel region PXA3. For example, the length L3 of the recess 321 can increase successively along the third direction DR3 or the fourth direction DR4 from the first pixel region PXA1 to the midpoint between the first pixel region PXA1 and the third pixel region PXA3, and can decrease successively along the third direction DR3 or the fourth direction DR4 from the midpoint to the third pixel region PXA3. The length L3 of the recess 321 can decrease as it approaches the first pixel region PXA1 or the third pixel region PXA3, and can increase as it moves away from the first pixel region PXA1 or the third pixel region PXA3.

[0110] The hole injection layer 510 can be formed along the contours of the first pixel electrode 201, the second pixel electrode 202, the third pixel electrode 203, and the pixel defining layer 300. The hole injection layer 510 can be formed along the contour of the upper surface of the pixel defining layer 300. The hole injection layer 510 can be formed along the contour of the first uneven structure 310 formed at the upper surface of the pixel defining layer 300 between the first pixel region PXA1 and the second pixel region PXA2. In addition, the hole injection layer 510 can be formed along the contour of the second uneven structure 320 formed at the upper surface of the pixel defining layer 300 between the first pixel region PXA1 and the third pixel region PXA3. Since the hole injection layer 510 is formed along the contour of the upper surface of the pixel defining layer 300 where the second uneven structure 320 is formed between the first pixel region PXA1 and the third pixel region PXA3, the circuit path length of the hole injection layer 510 between the first pixel region PXA1 and the third pixel region PXA3 can be increased.

[0111] The hole transport layer 520 and the electron transport layer 540 may be formed along the contour of the upper surface of the pixel defining layer 300. The hole transport layer 520 and the electron transport layer 540 may be formed along the contour of the second uneven structure 320 formed at the upper surface of the pixel defining layer 300 between the first pixel region PXA1 and the third pixel region PXA3. Since the hole transport layer 520 and the electron transport layer 540 are formed between the first pixel region PXA1 and the third pixel region PXA3 along the contour of the upper surface of the pixel defining layer 300 at which the second uneven structure 320 is formed, the electrical path length of the hole transport layer 520 between the first pixel region PXA1 and the third pixel region PXA3 and the electrical path length of the electron transport layer 540 between the first pixel region PXA1 and the third pixel region PXA3 may be increased.

[0112] The first pixel PX1 emitting red light may have a relatively low on-voltage. When the distance between the first pixel region PXA1 and the third pixel region PXA3 is relatively short, the first pixel PX1 may emit light in response to a lateral leakage current transmitted from the third pixel PX3 to the first pixel PX1 via the hole injection layer 510 according to the driving of the third pixel PX3, and color mixing may occur at low brightness. According to an embodiment, the hole injection layer 510 may be formed between the first pixel region PXA1 and the third pixel region PXA3 along the upper surface of the pixel defining layer 300 at which the second uneven structure 320 is formed, so that the electrical path length of the hole injection layer 510 between the first pixel region PXA1 and the third pixel region PXA3 may be increased; therefore, the resistance of the hole injection layer 510 between the first pixel region PXA1 and the third pixel region PXA3 may be increased. Therefore, the magnitude of the lateral leakage current between the first pixel PX1 and the third pixel PX3 via the hole injection layer 510 may be reduced, and color mixing at low brightness due to the lateral leakage current may be prevented.

[0113] Figure 7 , Figure 8 , Figure 9 , Figure 10 , Figure 11 and Figure 2 2 is a cross-sectional view showing a structure formed in a method of manufacturing an organic light emitting display device according to an embodiment. Figures 7 to 11 To describe the manufacturing reference Figures 1 to 3 The method of the OLED device described herein. Figures 7 to 11 The method of manufacturing an OLED device described can also be applied to Figure 4 The OLED device described and the reference Figure 5 and Figure 6 An OLED device is described.

[0114] ReferenceFigure 7 , a conductive material can be deposited on the substrate 100, and the conductive material can be patterned to form a first pixel electrode 201, a second pixel electrode 202, and a third pixel electrode 203.

[0115] Referring to Figure 8 , a photosensitive organic material can be deposited on the substrate 100 and on the first pixel electrode 201, the second pixel electrode 202, and the third pixel electrode 203 to form an initial pixel defining layer 301. In an embodiment, the initial pixel defining layer 301 may include a positive photosensitive organic material in which a portion exposed to light is removed. In another embodiment, the initial pixel defining layer 301 may include a negative photosensitive organic material in which a portion exposed to light is hardened.

[0116] A halftone mask 700 can be disposed above the initial pixel defining layer 301, and the initial pixel defining layer 301 can be exposed using the halftone mask 700. The halftone mask 700 may include a light-transmitting portion 710 (or a transparent portion 710), a light-blocking portion 720, and a semi-light-transmitting portion 730 (or a semi-transmissive portion 730 or a semi-transparent portion 730). The light-transmitting portion 710 can transmit light, the light-blocking portion 720 can block light, and the semi-light-transmitting portion 730 can transmit a portion of the light. The light transmittance of the semi-light-transmitting portion 730 can be less than the light transmittance of the light-transmitting portion 710 and greater than the light transmittance of the light-blocking portion 720.

[0117] Referring to Figure 9 , a pixel defining layer 300 can be formed on the substrate 100 and the pixel defining layer 300 can partially expose the first pixel electrode 201, the second pixel electrode 202, and the third pixel electrode 203.

[0118] The initially formed pixel defining layer 301 irradiated with light passing through the halftone mask 700 is developed to form the pixel defining layer 300. The portion of the initially formed pixel defining layer 301 corresponding to the light-transmitting portion 710 can be substantially completely removed, and the portion of the initially formed pixel defining layer 301 corresponding to the light-blocking portion 720 can be substantially retained. The portion of the initially formed pixel defining layer 301 corresponding to the semi-transmissive portion 730 can be partially removed. Accordingly, the pixel defining layer 300 can include a first opening portion OP1, a second opening portion OP2, and a third opening portion OP3 corresponding to the light-transmitting portion 710 and respectively exposing the first pixel electrode 201, the second pixel electrode 202, and the third pixel electrode 203 in part, can include a portion corresponding to the light-blocking portion 720 and having a first thickness, and can include a portion corresponding to the semi-transmissive portion 730 and having a second thickness smaller than the first thickness. The portion of the pixel defining layer 300 having the first thickness can correspond to the convex portion of the uneven structure 310 and the substantially flat (or planarized) upper surface, and the portion of the pixel defining layer 300 having the second thickness can correspond to the concave portion of the uneven structure 310.

[0119] The halftone mask 700 can be used to form the pixel defining layer 300 such that the opening portions OP1, OP2, and OP3 of the pixel defining layer 300 and the upper surface where the uneven structure 310 is formed can be formed by a single photolithography process. Accordingly, the manufacturing time and cost of the OLED device can be minimized.

[0120] Referring to Figure 10 , a photosensitive organic material can be deposited on the pixel defining layer 300, and the photosensitive organic material can be patterned to form the spacer 400. Then, a hole injection material can be deposited on the pixel defining layer 300 and the spacer 400 to form the hole injection layer 510. At least one of various methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, inkjet printing, laser printing, and laser-induced thermal imaging can be used to form the hole injection layer 510. The hole injection layer 510 can be formed along the contours of the first pixel electrode 201, the second pixel electrode 202, the third pixel electrode 203, and the pixel defining layer 300. The hole injection layer 510 can be formed along the contour of the uneven structure 310 formed on the upper surface of the pixel defining layer 300.

[0121] Referring to Figure 11, a hole transport material can be deposited on the hole injection layer 510 to form a hole transport layer 520. The hole transport layer 520 can be formed along the contour of the hole injection layer 510. The hole transport layer 520 can be formed along the contour of the uneven structure 310 formed on the upper surface of the pixel defining layer 300. Then, an organic light-emitting material can be ejected on the hole transport layer 520 to form a first emission layer 531, a second emission layer 532, and a third emission layer 533. At least one of various methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, inkjet printing, laser printing, and laser-induced thermal imaging can be used to form the hole transport layer 520, the first emission layer 531, the second emission layer 532, and the third emission layer 533.

[0122] Referring to Figure 2 , an electron transport material can be deposited on the hole transport layer 520 and on the first emission layer 531, the second emission layer 532, and the third emission layer 533 to form an electron transport layer 540. At least one of various methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, inkjet printing, laser printing, and laser-induced thermal imaging can be used to form the electron transport layer 540. When the OLED device includes an electron injection layer, an electron injection material can be deposited on the electron transport layer 540 to form an electron injection layer. Then, a conductive material can be deposited on the electron transport layer 540 to form a common electrode 600. The electron transport layer 540 and the common electrode 600 can be formed along the contours of the first emission layer 531, the second emission layer 532, the third emission layer 533, and the hole transport layer 520. The electron transport layer 540 and the common electrode 600 can be formed along the contour of the uneven structure 310 formed on the upper surface of the pixel defining layer 300.

[0123] The organic light-emitting display device according to an embodiment can be applied to display devices included in computers, laptop computers, mobile phones, smart phones, smart tablets, PMPs, PDAs, MP3 players, and the like.

[0124] Although example embodiments have been described with reference to the figures, the example embodiments can be modified without departing from the scope defined in the claims.

Claims

1. An organic light emitting display device, the organic light emitting display device comprises: a substrate; a first pixel electrode, a second pixel electrode, and a third pixel electrode, all stacked with the substrate, the first pixel electrode being spaced from the second pixel electrode in a first direction, and the third pixel electrode being spaced from the second pixel electrode in a second direction perpendicular to the first direction; a pixel defining layer including a first opening, a second opening, and a third opening that respectively expose portions of the first pixel electrode, the second pixel electrode, and the third pixel electrode, wherein the pixel defining layer further includes a first uneven surface and a first flat surface, wherein the first uneven surface faces the first flat surface and is disposed between the first opening and the second opening, and wherein the first flat surface is disposed between the first pixel electrode and the second pixel electrode and between the first uneven surface and the substrate; a first emission layer, a second emission layer, and a third emission layer respectively corresponding to the first opening, the second opening, and the third opening; a common electrode stacked with each of the first emission layer, the second emission layer, and the third emission layer; and a spacer disposed directly on one surface of the pixel defining layer, wherein the one surface of the pixel defining layer extends from an edge of the second opening to an edge of the third opening, is spaced from the first uneven surface, and is flat.

2. The organic light emitting display device according to claim 1, wherein, the first uneven surface is only disposed between the first emission layer and the second emission layer.

3. The organic light emitting display device according to claim 1, wherein, one surface of the pixel defining layer is arranged to be no farther from the common electrode than any other surface of the pixel defining layer, the one surface of the pixel defining layer is disposed between the first opening and the third opening, and is flat.

4. The organic light emitting display device according to claim 2, wherein, the minimum distance between the first emission layer and the second emission layer is less than the minimum distance between the first emission layer and the third emission layer.

5. The organic light emitting display device according to claim 1, wherein, the pixel defining layer further includes a second uneven surface and a second flat surface, wherein the second uneven surface is disposed between the first opening and the third opening and faces the second flat surface, and wherein the second flat surface is disposed between the first pixel electrode and the third pixel electrode and between the second uneven surface and the substrate.

6. The organic light emitting display device according to claim 5, wherein, the one surface of the pixel defining layer is arranged to be no farther from the common electrode than any other surface of the pixel defining layer.

7. The organic light emitting display device according to claim 1, wherein, the first uneven surface includes cavities and protrusions alternately arranged between the first opening and the second opening.

8. The organic light emitting display device according to claim 7, wherein, The length direction of each of the cavities is parallel to the edge of the first opening and parallel to the substrate.

9. The organic light-emitting display device according to claim 7, wherein, the cavities have equal lengths.

10. The organic light-emitting display device according to claim 7, wherein, the cavity includes a first cavity and a second cavity, wherein the first cavity is arranged closer to the first opening than the second cavity and is shorter than the second cavity.

11. The organic light-emitting display device according to claim 1, the organic light-emitting display device further comprises: a hole injection layer directly contacting each of the first pixel electrode, the second pixel electrode, the third pixel electrode, and the pixel defining layer, wherein the hole injection layer includes a cavity, and wherein the cavity is disposed between the first opening and the second opening.

12. The organic light-emitting display device according to claim 1, wherein, the first emission layer, the second emission layer, and the third emission layer are respectively configured to emit red light, green light, and blue light, and wherein the first emission layer and the second emission layer are adjacent to each other with no intermediate emission layer therebetween.

13. The organic light-emitting display device according to claim 1, the organic light-emitting display device further comprises: a hole injection layer directly contacting each of the first pixel electrode, the second pixel electrode, the third pixel electrode, and the pixel defining layer; and a hole transport layer disposed between each of the first emission layer, the second emission layer, and the third emission layer and the hole injection layer, wherein the hole transport layer is stacked with the pixel defining layer and includes a cavity, and wherein the cavity is disposed between the first opening and the second opening.

14. The organic light-emitting display device according to claim 1, the organic light-emitting display device further comprises: an electron transport layer disposed between each of the first emission layer, the second emission layer, and the third emission layer and the common electrode, and the electron transport layer is stacked with the pixel defining layer.

15. An organic light-emitting display device, the organic light-emitting display device comprises: a common electrode; a first pixel electrode stacked with the common electrode; a first emission layer disposed between the first pixel electrode and the common electrode; a second pixel electrode; a second emission layer disposed between the second pixel electrode and the common electrode; a third pixel electrode; and a third emission layer disposed between the third pixel electrode and the common electrode, The pixel defining layer includes a first opening, a second opening, a third opening, a first flat surface, a second flat surface, a third flat surface, and an uneven surface. Among them, the first opening partially exposes the first pixel electrode; the second opening partially exposes the second pixel electrode; the third opening partially exposes the third pixel electrode; the first flat surface is opposite to the uneven surface and is disposed between the first pixel electrode and the second pixel electrode; the uneven surface is disposed between the first opening and the second opening; the second flat surface is opposite to the third flat surface and is disposed between the second pixel electrode and the third pixel electrode; and the third flat surface is disposed between the second opening and the third opening; and a spacer, which is directly disposed on the third flat surface and is spaced apart from the uneven surface, wherein the first pixel electrode is spaced apart from the second pixel electrode in a first direction, and the third pixel electrode is spaced apart from the second pixel electrode in a second direction perpendicular to the first direction.

16. The organic light emitting display device according to claim 15, wherein, the uneven surface includes cavities and protrusions alternately arranged between the first opening and the second opening.

17. A method for manufacturing an organic light emitting display device, the method comprises the following steps: forming a first pixel electrode, a second pixel electrode, and a third pixel electrode on a substrate, wherein the first pixel electrode is spaced apart from the second pixel electrode in a first direction, and the third pixel electrode is spaced apart from the second pixel electrode in a second direction perpendicular to the first direction; forming a pixel defining layer on the substrate, wherein the pixel defining layer includes a first opening, a second opening, and a third opening that respectively partially expose the first pixel electrode, the second pixel electrode, and the third pixel electrode, and the pixel defining layer further includes an uneven surface and a first flat surface, the uneven surface is opposite to the first flat surface and is disposed between the first opening and the second opening, and the first flat surface is disposed between the first pixel electrode and the second pixel electrode and between the uneven surface and the substrate; forming a spacer, the spacer is directly disposed on a surface of the pixel defining layer, wherein the surface of the pixel defining layer extends from the edge of the second opening to the edge of the third opening, is spaced apart from the uneven surface, and is flat; forming a first emission layer, a second emission layer, and a third emission layer, the first emission layer, the second emission layer, and the third emission layer respectively corresponding to the first opening, the second opening, and the third opening; and forming a common electrode, the common electrode being stacked on each of the first emission layer, the second emission layer, and the third emission layer.

18. The method according to claim 17, wherein, The uneven surface includes cavities and protrusions alternately arranged between the first opening and the second opening.

19. The method according to claim 18, wherein, the step of forming the pixel defining layer includes: forming a material layer on the substrate, the first pixel electrode, the second pixel electrode, and the third pixel electrode; providing a halftone mask above the material layer; and using the halftone mask to expose and develop the material layer.

20. The method according to claim 19, wherein, the halftone mask includes a light-transmitting portion, a light-blocking portion, and a semi-transmissive portion, wherein the light-transmitting portion corresponds to the first opening, the second opening, and the third opening, wherein the light-blocking portion corresponds to the protrusions of the uneven surface, and wherein the semi-transmissive portion corresponds to the cavities of the uneven surface.

Images