Light-emitting display device

Abstract

To provide a display device with improved light extraction efficiency. [Solution] The light-emitting display device according to this disclosure includes a substrate, a driving element layer, a first planarization film, a second planarization film, an anode electrode, a light-emitting layer, and a cathode electrode. A plurality of pixels are arranged on the substrate. The driving element layer is arranged on the substrate. The first planarization film covers the driving element layer. The second planarization film is arranged within each pixel on the first planarization film. The anode electrode is arranged on the upper surface of the second planarization film. The light-emitting layer is arranged on the first planarization film, the second planarization film, and the anode electrode. The cathode electrode is arranged on the light-emitting layer.

Description

Technical Field

[0001] This specification relates to a light-emitting display device. In particular, this specification relates to a bottom-emitting display device equipped with micromirrors and having improved light extraction efficiency.

Background Art

[0002] Among display devices, light-emitting display devices have the advantages of a wide viewing angle, excellent contrast between light and dark, and fast response speed, and are attracting attention as next-generation display devices. The light-emitting elements used in light-emitting display devices generally include a light-emitting layer made of an organic or inorganic material between an anode electrode and a cathode electrode.

[0003] In the light-emitting element, holes are supplied from the anode electrode and electrons are supplied from the cathode electrode, and electrons and holes are combined in the light-emitting layer to generate excitons. As the excitons change from the excited state to the ground state, the fluorescent molecules in the light-emitting layer emit light to represent the hue.

[0004] A part of the light emitted from the light-emitting layer of the light-emitting display device may be totally reflected inside the electrode layer with a high refractive index or by total reflection occurring at the interface between the light-emitting layer and the electrode and / or the interface between the substrate and the air layer, and may be extinguished without being emitted to the outside. As a result, a problem may occur in that the light extraction efficiency decreases.

[0005] To overcome such problems, methods have been developed to form microlenses or microcavity structures inside the element to improve the light extraction efficiency of the light-emitting element. However, these structures improve the light extraction efficiency of the light emitted in the vertical direction of the display device, but cannot extract the light emitted in the horizontal direction into the vertical direction. Therefore, there is a limit to improving the light extraction efficiency by conventional methods.

Summary of the Invention

Problems to be Solved by the Invention

[0006] The purpose of this disclosure is to overcome the problems of the prior art and to provide a bottom-emitting display device that improves light extraction efficiency by extracting light generated in the light-emitting layer that could be confined and annihilated inside the device by total internal reflection to the outside.

[0007] Another object of this disclosure is to provide a bottom-emitting display device that improves brightness maintenance rate and light extraction efficiency by arranging a micromirror structure at the edge of the light-emitting region and maximizing the area of ​​the light-emitting region.

[0008] Another object of this disclosure is to provide a bottom-emitting display device that improves light extraction efficiency by extracting light that is lost due to total internal reflection in the central part of the anode electrode.

[0009] Another object of this disclosure is to provide a bottom-emitting display device that has a trench structure between pixels having a micromirror structure, thereby blocking horizontal leakage current and improving color purity. [Means for solving the problem]

[0010] To achieve the above objective, the light-emitting device according to this disclosure includes a substrate, a driving element layer, a first planarization film, a second planarization film, an anode electrode, a light-emitting layer, and a cathode electrode. A plurality of pixels are arranged on the substrate. The driving element layer is disposed on the substrate. The first planarization film covers the driving element layer. The second planarization film is disposed within each pixel on the first planarization film. The anode electrode is disposed on the upper surface of the second planarization film. The light-emitting layer is disposed on the first planarization film, the second planarization film, and the anode electrode. The cathode electrode is disposed on the light-emitting layer.

[0011] As an example, the substrate further includes, among a plurality of pixels, adjacent first and second pixels, a first light-emitting diode placed in the first pixel, a second light-emitting diode placed in the second pixel, and a dummy anode electrode placed between the first and second light-emitting diodes.

[0012] As an example, the light-emitting display device further includes at least one trench located between a first light-emitting diode and a second light-emitting diode.

[0013] As an example, it includes a trench recessed into the first planarization film between the first light-emitting diode and the dummy anode electrode. [Effects of the Invention]

[0014] The light-emitting display device according to this disclosure has a structure in which almost all of the light emitted from the light-emitting layer is confined inside the element and extracted to the outside without being extinguished, thereby providing a bottom-emitting type display device with improved light emission efficiency.

[0015] The light-emitting display device according to this disclosure can provide a bottom-emitting display device that reduces the non-light-emitting area and improves light extraction efficiency by arranging micromirrors (or reflective parts) without using a bank that covers the edge of the pixel electrodes.

[0016] The light-emitting display device according to this disclosure has a structure in which a high-refractive-index layer having a similar refractive index to that of the anode electrode is stacked below the anode electrode, and a low-refractive-index layer is placed below the anode electrode. Therefore, it is possible to provide a bottom-emitting display device that further improves light extraction efficiency by extracting light that could be annihilated by total internal reflection inside the center of the anode electrode to the outside.

[0017] The light-emitting display device according to this disclosure has a structure in which trenches are placed between adjacent pixels, and the light-emitting layer is separated for each pixel. Therefore, it is possible to provide a bottom-emitting display device with improved color purity by blocking and / or eliminating horizontal leakage current generated by the linking of light-emitting layers.

[0018] The effects obtained from this disclosure are not limited to those mentioned above, and other effects not mentioned above can be clearly understood by a person with ordinary skill in the art to which this disclosure pertains from the following description. [Brief explanation of the drawing]

[0019] [Figure 1] This is a diagram showing a schematic configuration of a light-emitting display device according to the present disclosure. [Figure 2] This is a diagram showing a circuit configuration of one pixel constituting a light-emitting display device according to the present disclosure. [Figure 3] This is a plan view showing the structure of a pixel array according to an example of the present disclosure. [Figure 4] This is an enlarged cross-sectional view showing the structure of a light-emitting display device according to an example of the present disclosure, taken along line I-I' of FIG. 3. [Figure 5] This is an enlarged cross-sectional view showing a light extraction path in a light-emitting display device according to an example of the present disclosure, taken along line II-II’ of FIG. 3. [Figure 6] This is an enlarged cross-sectional view showing the structure of a light-emitting display device according to the first embodiment of the present disclosure, taken along line II-II’ of FIG. 3. [Figure 7] This is an enlarged cross-sectional view showing the structure of a light-emitting display device according to the second embodiment of the present disclosure, taken along line II-II’ of FIG. 3. [Figure 8] This is an enlarged cross-sectional view showing the structure of a light-emitting display device according to the third embodiment of the present disclosure, taken along line II-II’ of FIG. 3. [Figure 9] This is an enlarged cross-sectional view showing the structure of a light-emitting display device according to the fourth embodiment of the present disclosure, taken along line II-II’ of FIG. 3. [Figure 10] This is a plan view showing the structure of a light-emitting display device according to the fifth embodiment of the present disclosure.

Embodiments for Carrying Out the Invention

[0020] The advantages and features of the present disclosure, and the method for achieving them, will become clear by referring to an example described in detail below together with the accompanying drawings. However, the present disclosure is not limited to the example disclosed below, but is embodied in various different forms, and merely an example of the present disclosure is provided to complete the present disclosure and to fully inform those having ordinary knowledge in the technical field to which the invention of the present disclosure belongs of the scope of the invention. The invention of the present disclosure is only defined by the claims.

[0021] The shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings for explaining an example of the present disclosure are exemplary, and thus are not limited to the matters shown herein. Throughout the specification, the same reference numerals refer to the same components. In addition, when explaining an example of the present disclosure, if it is determined that a detailed description of related known technologies may unnecessarily obscure the gist of the application, the detailed description thereof will be omitted.

[0022] Exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The same reference numerals are used throughout the drawings to refer to the same or similar components. Similar reference signs that have already been used to indicate similar components in other drawings in the specification of the present disclosure are used for one component as much as possible. In the following description, if functions and configurations known to those having ordinary knowledge in the technical field to which the present disclosure belongs are irrelevant to the essential configuration of the present disclosure, the detailed description thereof may be omitted. The terms described in the specification of the present disclosure shall be understood as follows.

[0023] When terms such as "including", "having", "consisting of", etc. are used in the specification of the present disclosure, other parts may be added unless "only" is used. When a component is expressed in the singular, it includes the case of including a plurality unless there is a special explicit description.

[0024] In interpreting a component, it is interpreted as including an error range even without a separate explicit description.

[0025] When describing the positional relationship between two parts, for example, using phrases like "on top," "above," "below," or "next to," one or more other parts may be located between the two parts, unless "immediately" or "directly" is used.

[0026] When describing temporal relationships, for example, when a temporal sequence is described using phrases like "after," "following," "next," or "before," it can include cases that are not continuous unless "immediately" or "directly" is used.

[0027] While terms such as "first," "second," etc., are used to describe various components, these components are not limited by these terms. These terms are simply used to distinguish one component from another. Therefore, the first component referred to below may also be the second component within the technical concept of this disclosure.

[0028] In describing the components of this specification, terms such as 1st, 2nd, A, B, (a), (b), etc., may be used. Such terms are used solely to distinguish a component from other components, and do not limit the nature, order, sequence, or number of the component in question. Where it is stated that a component "connects," "joins," or "connects" another component, it should be understood that the component may be directly connected or connected to the other component, but other components may also "intersect" between each component that can be indirectly connected or connected without any special explicit description.

[0029] The term "at least one" must be understood to include all possible combinations of one or more related items. For example, "at least one of item 1, item 2, and item 3" can mean not just each of item 1, item 2, or item 3 individually, but all possible combinations of items that can be presented from two or more of items 1, item 2, and item 3.

[0030] The features of some of the examples in this disclosure can be combined or linked together in part or in whole, allowing for various technical interdependencies and drives, and each example may be implementable independently of others, or they may be implemented together in relation to each other.

[0031] Hereinafter, an example of a light-emitting display device according to this disclosure will be described in detail with reference to the attached figures. In assigning reference numerals to the components in each figure, the same component may, as far as possible, have the same reference numeral even if it is shown in different figures.

[0032] The present disclosure will be described in detail below with reference to the attached figures. Figure 1 is a diagram showing the schematic configuration of the light-emitting display device according to the present disclosure. In Figure 1, the X axis indicates the direction parallel to the scan wiring, the Y axis indicates the direction parallel to the data wiring, and the Z axis indicates the height direction of the display device.

[0033] Referring to Figure 1, the light-emitting display device according to this disclosure includes a substrate 110, a gate (or scan) drive unit 200, a pad unit 300, a source drive integrated circuit 410, a flexible wiring film 430, a circuit board 450, and a timing control unit 500.

[0034] The substrate 110 may include an insulating material or a flexible material. The substrate 110 may be made of glass, metal, or plastic, but is not limited to these. If the light-emitting display device is a flexible display device, the substrate 110 may also be made of a flexible material such as plastic. For example, it may include a transparent polyimide material.

[0035] The circuit board 110 can be divided into a display area (AA) and a non-display area (NDA). The display area (AA) is the area where the image is displayed and can be defined as most of the area of ​​the circuit board 110, including the central part, but is not limited to this. Scan lines (or gate lines), data lines, and unit pixels (UP) are arranged in the display area (AA). The unit pixels (UP) are arranged in a matrix manner. One unit pixel (UP) contains multiple pixels (P), and each of the multiple pixels (P) contains a scan line and a data line.

[0036] The non-display area (NDA) is an area where no image is displayed, and can be defined on the edge of the substrate 110 so as to surround all or part of the display area (AA). The gate drive unit 200 and the pad unit 300 can be formed in the non-display area (NDA).

[0037] The gate drive unit 200 supplies scan (or gate) signals to the scan wiring based on gate control signals input from the timing control unit 500. The gate drive unit 200 can be formed in the non-display area (NDA) on one side of the display area (AA) of the base substrate 110 using the GIP (gate driver in panel) method. The GIP method refers to a structure in which the gate drive unit 200 is directly formed on the substrate 110.

[0038] The pad section 300 supplies data signals to the data wiring based on data control signals input from the timing control unit 500. The pad section 300 is manufactured using a drive chip, mounted on a flexible wiring film 430, and can be attached to the non-display area (NDA) on one side of the display area (AA) of the substrate 110 using the TAB (tape automated bonding) method.

[0039] The source-driven integrated circuit 410 receives digital video data and source control signals from the timing control unit 500. The source-driven integrated circuit 410 converts the digital video data into analog data voltages according to the source control signals and supplies them to the data wiring. If the source-driven integrated circuit 410 is manufactured as a chip, it can be mounted on the flexible wiring film 430 using the COF (chip-on-film) or COP (chip-on-plastic) method.

[0040] The flexible wiring film 430 can have wiring formed on it that connects the pad portion 300 to the source drive integrated circuit 410, and wiring that connects the pad portion 300 to the circuit board 450. The flexible wiring film 430 is attached to the pad portion 300 using an anisotropic conducting film, thereby connecting the wiring on the pad portion 300 and the flexible wiring film 430.

[0041] The circuit board 450 can be attached to the flexible wiring film 430. The circuit board 450 can mount multiple circuits embodied as drive chips. For example, a timing control unit 500 can be mounted on the circuit board 450. The circuit board 450 may be a printed circuit board or a flexible printed circuit board.

[0042] The timing control unit 500 receives digital video data and timing signals from an external system board via cables on the circuit board 450. Based on the timing signals, the timing control unit 500 generates gate control signals to control the operating timing of the gate drive unit 200 and source control signals to control the source drive integrated circuit 410. The timing control unit 500 supplies the gate control signals to the gate drive unit 200 and the source control signals to the source drive integrated circuit 410. Depending on the product, the timing control unit 500 may be formed with the source drive integrated circuit 410 and a single drive chip and mounted on the board 110.

[0043] The structure of an example of a light-emitting display device according to this disclosure will be described below with reference to Figures 2 to 4. Figure 2 is a diagram showing the circuit configuration of a single pixel constituting the light-emitting display device according to this disclosure. Figure 3 is a plan view showing the structure of a pixel array according to an example of this disclosure. Figure 4 is an enlarged cross-sectional view showing the structure of an example of a light-emitting display device according to this disclosure, cut along line I-I' in Figure 3.

[0044] Referring to Figures 2 to 4, a single pixel of the light-emitting device is defined by scan wiring (SL), data wiring (DL), and drive current wiring (VDD). Inside a single pixel of the light-emitting device, there is a switching thin-film transistor (ST), a drive thin-film transistor (DT), a light-emitting diode (OLE), and an auxiliary capacitor (Cst). A high potential voltage is applied to the drive current wiring (VDD) to drive the light-emitting diode (OLE).

[0045] For example, a switching thin-film transistor (ST) can be placed at the intersection of scan paths (SL) and data paths (DL). The switching thin-film transistor (ST) includes a gate electrode (SG), a semiconductor layer (SA), a source electrode (SS), and a drain electrode (SD). The gate electrode (SG) is connected to the scan path (SL). The source electrode (SS) is connected to the data path (DL), and the drain electrode (SD) is connected to the drive thin-film transistor (DT). The semiconductor layer (SA) is placed on the gate insulating film (GI) so as to overlap with the gate electrode (SG). The portion of the semiconductor layer (SA) that overlaps with the gate electrode (SG) is defined as the channel region.

[0046] An intermediate insulating film (IL) is stacked on a semiconductor layer (SA). A source electrode (SS) and a drain electrode (SD) are formed on the intermediate insulating film (IL). The source electrode (SS) is connected to one side of the semiconductor layer (SA) via a contact hole formed in the intermediate insulating film (IL). The drain electrode (SD) is connected to the other side of the semiconductor layer (SA) via another contact hole formed in the intermediate insulating film (IL). A switching thin-film transistor (ST) has the function of selecting the pixel to be driven by applying a data signal to a driving thin-film transistor (DT).

[0047] A driving thin-film transistor (DT) functions to drive the light-emitting diode (OLE) of a pixel selected by a switching thin-film transistor (ST). The driving thin-film transistor (DT) includes a gate electrode (DG), a semiconductor layer (DA), a source electrode (DS), and a drain electrode (DD). The gate electrode (DG) of the driving thin-film transistor (DT) is connected to the drain electrode (SD) of the switching thin-film transistor (ST). For example, the drain electrode (SD) of the switching thin-film transistor (ST) is connected via a drain contact hole (DH) that penetrates the gate insulating film (GI) covering the gate electrode (DG) of the driving thin-film transistor (DT). The drain electrode (DD) is connected to a drive current trace (VDD), and the source electrode (DS) is connected to the anode electrode (ANO) of the light-emitting diode (OLE). An auxiliary capacitor (Cst) is placed between the gate electrode (DG) of the driving thin-film transistor (DT) and the anode electrode (ANO) of the light-emitting diode (OLE).

[0048] An intermediate insulating film (IL) is stacked on a semiconductor layer (DA). A source electrode (DS) and a drain electrode (DD) are formed on the intermediate insulating film (IL). The source electrode (DS) is connected to one side of the semiconductor layer (DA) via a contact hole formed in the intermediate insulating film (IL). The drain electrode (DD) is connected to the other side of the semiconductor layer (DA) via another contact hole formed in the intermediate insulating film (IL).

[0049] The drive thin-film transistor (DT) is placed between the drive current wiring (VDD) and the light-emitting diode (OLE). The drive thin-film transistor (DT) adjusts the amount of current flowing from the drive current wiring (VDD) to the light-emitting diode (OLE) according to the magnitude of the voltage of the gate electrode (DG) connected to the drain electrode (SD) of the switching thin-film transistor (ST).

[0050] A light-emitting diode (OLE) includes an anode electrode (ANO), an emissive layer (EL), and a cathode electrode (CAT). The OLE emits light in response to a current regulated by a driving thin-film transistor (DT). To reiterate, the amount of light emitted by the OLE is adjusted by the current regulated by the driving thin-film transistor (DT), thus allowing for adjustment of the brightness of a light-emitting display device. The anode electrode (ANO) of the OLE is connected to the source electrode (DS) of the driving thin-film transistor (DT), and the cathode electrode (CAT) is connected to a low-voltage wiring (VSS) to which a low-voltage voltage is supplied. That is, the OLE is driven by a low-voltage voltage and a high-voltage voltage regulated by the driving thin-film transistor (DT).

[0051] A protective film (PAS) is laminated on the surface of a substrate 110 on which thin-film transistors (ST, DT) are formed. The protective film (PAS) is preferably formed of an inorganic film such as silicon oxide (SiOx) or silicon nitride (SiNx). The thin-film components from the gate electrodes (SG, DG) and scan wiring (SL) laminated on the substrate 110 to the protective film (PAS) can be named the "driving element layer". The driving element layer includes thin-film transistors for driving light-emitting diodes (OLEs) contained in the "light-emitting element layer" formed thereon.

[0052] A color filter (CF) is formed on the protective layer (PAS). One color filter (CF) is placed for each pixel. For example, one color filter (CF) can be placed for each pixel from among red, blue, and green. Alternatively, one color filter (CF) can be placed for each pixel from among red, blue, green, and white.

[0053] A first planarization film (PL1) is stacked on the color filter (CF). The first planarization film (PL1) is a thin film used to flatten the surface of the substrate 110 on which the thin-film transistors (ST, DT) are formed, as the surface is not uniform. To make the height differences uniform, the first planarization film (PL1) can be formed from an organic material.

[0054] A second planarization film (PL2) is formed on the first planarization film (PL1). The second planarization film (PL2) preferably has the same shape as the anode electrode (ANO) formed on it, and is slightly larger in size than the anode electrode (ANO). For example, the second planarization film (PL2) can be formed so as not to overlap with scan wiring (SL), data wiring (DL), and drive current wiring (VDD). The first planarization film (PL1) is coated over the entire upper surface of the substrate 110. On the other hand, the second planarization film (PL2) is patterned so that it has an isolated island-like shape, one for each pixel.

[0055] The protective film (PAS), color filter (CF), first planarization film (PL1), and second planarization film (PL2) have pixel contact holes (PH) that expose a portion of the source electrode (DS) of the driving thin-film transistor (DT). An anode electrode (ANO) is formed on the upper part of the second planarization film (PL2). The anode electrode (ANO) is connected to the source electrode (DS) of the driving thin-film transistor (DT) via the pixel contact hole (PH). In the figure, the second planarization film (PL2) is shown in a structure where a portion of it overlaps with the driving thin-film transistor (DT), the pixel contact hole (PH), and the auxiliary capacitor (Cst). However, the second planarization film (PL2) can also be formed so as not to overlap with the driving thin-film transistor (DT), the pixel contact hole (PH), and the auxiliary capacitor (Cst).

[0056] The anode electrode (ANO) can vary in composition depending on the light-emitting structure of the light-emitting diode (OLE). For example, in the case of a bottom-emitting type that provides light towards the substrate 110, it can be formed from a transparent conductive material. In the case of a type that emits light in the upper direction opposite to the substrate 110, it can be formed from a metallic material with excellent light reflectivity. In this case, it can have a structure in which a transparent conductive layer and a metal layer are laminated.

[0057] In the case of a bottom-emitting type, the anode electrode (ANO) is made of a transparent conductive material (TCO) or a semi-transmissive conductive material. For example, the anode electrode (ANO) can be made of a transparent conductive material such as indium-tin oxide (ITO), indium-zinc oxide (IZO), or indium-zinc-tin oxide (IZTO). Alternatively, the anode electrode (ANO) can be formed as a semi-transmissive layer made of magnesium (Mg), silver (Ag), or an alloy of magnesium (Mg) and silver (Ag) with a thickness of less than 100 nm. Such an anode electrode (ANO) can be referred to as the first electrode or transparent electrode.

[0058] A light-emitting layer (EL) is laminated on the anode electrode (ANO). The light-emitting layer (EL) is continuously arranged on the entire surface of the substrate 110. A cathode electrode (CAT) is laminated on the light-emitting layer (EL). The cathode electrode (CAT) is also continuously arranged on the entire surface of the substrate 110. The laminated structure of the anode electrode (ANO), light-emitting layer (EL), and cathode electrode (CAT) forms a light-emitting diode (OLE).

[0059] The cathode electrode (CAT) is preferably formed from a metallic material with excellent light reflectivity. For example, the cathode electrode (CAT) can be formed from a metallic material with excellent light reflectivity to a thickness of at least 2000 Å to 3000 Å (or 200 nm to 300 nm). Here, the metallic material with excellent light reflectivity may be at least one of the following metals: aluminum (Al), magnesium (Mg), calcium (Ca), silver (Ag), or alloys or combinations thereof (e.g., aluminum-magnesium alloy (AlMg)). As another example, the cathode electrode (CAT) can be formed as a thin film layer with high reflectivity, such as a laminated structure of aluminum (Al) and titanium (Ti) (Ti / Al / Ti), a laminated structure of aluminum (Al) and ITO (ITO / Al / ITO), a silver (Ag) alloy, and a laminated structure of silver (Ag) alloy and ITO (ITO / Ag alloy / ITO). Silver (Ag) alloys can be alloys of silver (Ag), palladium (Pd), and copper (Cu), among others. Such cathode electrodes (CATs) can be referred to as second electrodes, reflecting electrodes, or counter electrodes.

[0060] An anode electrode (ANO), an emissive layer (EL), and a cathode electrode (CAT) are stacked to form a light-emitting diode (OLE). The light-emitting display device according to this disclosure has a structure in which one light-emitting diode (OLE) is arranged on a second planarization film (PL2) that is patterned in an island-like protruding shape within each pixel (P).

[0061] The thin film layers from the color filter (CF) stacked on the protective film (PAS) to the cathode electrode (CAT) can be named the "light-emitting element layer." In some cases, the color filter (CF) can be classified as part of the driving element layer.

[0062] More specifically, within each pixel (P), a second planarization layer (PL2) has a constant thickness and is formed in an island-like manner, with an anode electrode (ANO) formed only on the upper surface of the second planarization layer (PL2). The light-emitting layer (EL) is stacked, covering the upper surface of the first planarization layer (PL1), the etched sidewalls of the second planarization layer (PL2), the upper edge surface of the second planarization layer (PL2), and the upper surface of the anode electrode (ANO). The cathode electrode (CAT) is also stacked with the same profile as the light-emitting layer (EL). As a result, the cathode electrode (CAT) has a downward-concave "∩" shape. Because the cathode electrode (CAT) is made of a metallic material with excellent light reflectivity, it has a structure in which concave micromirrors are formed along the periphery of the second planarization layer (PL2).

[0063] In the case of bottom-emitting devices, a disadvantage may be that the area ratio of the aperture region to the pixel region is small due to the thin-film transistors (ST, DT), auxiliary capacitors (Cst), scan wiring (SL), data wiring (DL), and drive current wiring (VDD). The light-emitting device according to this disclosure provides a structure equipped with micromirrors so that even if the proportion occupied by the aperture region is small, the light generated in the light-emitting layer can be provided without loss towards the substrate 110 located below. The mechanism by which the light emission efficiency is improved by the micromirrors will be explained below with reference to Figure 5. Figure 5 is an enlarged cross-sectional view showing the light extraction path in a light-emitting device according to an example of this disclosure, cut along line II-II' in Figure 3.

[0064] Referring to Figure 5, the optical path (1) for light emitted from the light-emitting layer (EL) in the edge region of the anode electrode (ANO) will be explained. The light generated in the light-emitting layer (EL) is transmitted as a spherical wave. It is emitted in all 360 degrees on the cross-sectional view. Of this, the light emitted at the top is reflected by the cathode electrode (CAT) and proceeds back to the bottom. That is, the light generated in the light-emitting layer (EL) is radiated in the downward 180-degree direction. This light is incident on the anode electrode (ANO). Since the anode electrode (ANO) is made of a transparent conductive material, 60-70% of the light passes through the anode electrode (ANO) and through the color filter (CF) located at the bottom and is emitted to the outside of the substrate 110.

[0065] On the other hand, the anode electrode (ANO) is a transparent conductive material with a refractive index of approximately 2.0 to 2.3. The luminescent layer (EL) is in contact with the upper part of the anode electrode (ANO), and the planarization film (PL) is in contact with the lower part. The luminescent layer (EL) and the planarization film (PL) can have refractive indices of approximately 1.3 to 1.5. As a result, a structure is formed in which the anode electrode (ANO) with a high refractive index is interposed between the low refractive index layers. Therefore, of the light incident on the anode electrode (ANO), approximately 30 to 40% of the light corresponding to the total internal reflection condition propagates horizontally (in the X-axis direction) inside the anode electrode (ANO).

[0066] Furthermore, depending on the material of the light-emitting layer (EL), the refractive index of the EL may be the same as, or very similar to, the refractive index of the anode electrode (ANO). In this case, the light emitted from the EL that undergoes total internal reflection at the interface between the anode electrode (ANO) and the planarization film (PL) can be confined between the cathode electrode (CAT) and the planarization film (PL) and propagate horizontally (in the X-axis direction).

[0067] Thus, light confined within the anode electrode (ANO) or between the cathode electrode (CAT) and the planarization film (PL) and propagating horizontally is emitted from the end of the anode electrode (ANO) and reflected downward by the cathode electrode (CAT), which has a micromirror structure opposite it. In the absence of the micromirror structure formed by the protrusions of the planarization film (PL), light that would otherwise be emitted horizontally and annihilated is extracted downward by the micromirrors, thereby improving the light extraction efficiency.

[0068] Here, in order for the light reflected by the cathode electrode (CAT) having a micromirror structure to be emitted in the downward front direction, it is necessary to adjust the inclination angle of the cathode electrode (CAT) laminated on the etched side surface where the step of the planarization film (PL) is formed. As an example, the inclination angle (θ) that the inclined surface of the cathode electrode (CAT) makes with the horizontal plane of the substrate 110 is preferably any value in the range of 40 to 80 degrees. More preferably, the inclination angle can be any value in the range of 50 to 75 degrees. Since the cathode electrode (CAT) is laminated along the step shape of the first planarization film (PL1) and the second planarization film (PL2), the inclination angle (θ) of the cathode electrode (CAT) may be substantially the same as the inclination angle (θ') of the side wall of the second planarization film (PL2) protruding on the first planarization film (PL1). Therefore, it is preferable to form the inclination angle (θ') between the upper surface of the first planarization film (PL1) and the side wall of the second planarization film (PL2) to be 50 to 75 degrees.

[0069] Next, we will explain the optical path (2) for light emitted from the light-emitting layer (EL) in the central region of the anode electrode (ANO). The light generated in the light-emitting layer (EL) is radiated downwards in a 180-degree direction by the same mechanism as described above. Since the anode electrode (ANO) is made of a transparent conductive material, 60-70% of the light passes through the anode electrode (ANO), through the color filter (CF) located below, and is emitted to the outside of the substrate 110.

[0070] However, of the light incident on the anode electrode (ANO), approximately 30-40% that satisfies the total internal reflection condition propagates horizontally (in the X-axis direction) within the anode electrode (ANO). In particular, light generated in the central region of the pixel undergoes repeated total internal reflection processes within the anode electrode (ANO), and the length of the transmitted light path (2) is longer than the length of the aforementioned light path (1). Therefore, before passing through the edge of the anode electrode (ANO) and being emitted, it can be lost as thermal energy within the anode electrode (ANO). Generally, if light propagates for a length of 20 μm or more within the anode electrode (ANO), it can be annihilated.

[0071] This disclosure proposes a method for minimizing the amount of light lost due to total internal reflection inside the anode electrode (ANO). As an example, this disclosure is characterized by using a transparent organic material for the second planarization film (PL2) that contacts the anode electrode (ANO), which has a refractive index equal to or approximately 0.2 lower than that of the anode electrode (ANO).

[0072] In this case, the light emitted from the light-emitting layer (EL) is emitted in the same manner as in the optical path (3). The light generated in the light-emitting layer (EL) is radiated downwards in a 180-degree direction by the same mechanism as described above. Since the anode electrode (ANO) is made of a transparent conductive material and the second planarization film (PL2) has a refractive index similar to that of the anode electrode (ANO), 90-98% of the light passes through the anode electrode (ANO) and the second planarization film (PL2). The light that has passed through the second planarization film (PL2) is incident on the first planarization film (PL1). Since the first planarization film (PL1) has a refractive index of 1.4-1.5, 60-70% of the light incident on the second planarization film (PL2) passes through the first planarization film (PL1), through the color filter (CF) located at the bottom, and is emitted to the outside of the substrate 110.

[0073] However, of the light incident on the second planarization layer (PL2), approximately 30-40% of the light that satisfies the total internal reflection condition at the interface with the first planarization layer (PL1) is re-incident to the anode electrode (ANO) and undergoes total internal reflection again at the upper surface of the anode electrode (ANO). In other words, it propagates horizontally (in the X-axis direction) within the anode electrode (ANO) and the second planarization layer (PL2).

[0074] Unlike optical paths (1) and (2), the second planarization film (PL2), which has a thickness of approximately 1 to 1.5 μm, widens the space for total internal reflection, and significantly reduces the number of times total internal reflection occurs. As a result, light emitted in the central region of the pixel and totally reflected can also be reflected downward by the cathode electrode (CAT) having a micromirror structure.

[0075] The light-emitting device according to this disclosure can improve light extraction efficiency by extracting light generated in the light-emitting layer (EL) using a cathode electrode (CAT) having a micromirror structure formed by a stepped structure of a second planarization film (PL2) and a planarization film (PL) that protrudes in an island-like manner. In particular, by configuring the second planarization film (PL2) to have the same or slightly lower refractive index as the anode electrode (ANO), and the first planarization film (PL1) located below the second planarization film (PL2) to have a low refractive index, light that could be lost by total internal reflection can be extracted to the outside, further improving light extraction efficiency.

[0076] For example, the anode electrode (ANO) can have a refractive index of 2.0 to 2.3. The second planarization film (PL2) can have a refractive index of 1.8 to 2.0, which is the same as or about 0.2 lower than that of the anode electrode (ANO). On the other hand, the first planarization film (PL1) can have a refractive index of 1.3 to 1.5, which is 0.5 or more lower than that of the second planarization film (PL2).

[0077] The above describes the structural features of a single pixel in the light-emitting display device according to this disclosure. Below, we will describe the structural features for eliminating horizontal leakage current between adjacent pixels. Since there are several possible structural features for eliminating horizontal leakage current, they will be described separately for each example. [Examples]

[0078] The structure of the light-emitting device according to the first embodiment of this disclosure will be described below with reference to Figure 6. Figure 6 is an enlarged cross-sectional view showing the structure of the light-emitting device according to the first embodiment of this disclosure, cut along line II-II' in Figure 3.

[0079] The light-emitting device according to this disclosure has a structure in which a second planarization film (PL2), which is a high refractive index layer, is laminated on a first planarization film (PL1), which is a low refractive index layer. In particular, the second planarization film (PL2) is patterned in an island-like manner, and the cathode electrode (CAT) is configured to form micromirrors while enclosing the second planarization film (PL2). Furthermore, total internal reflection occurs at the interface between the first planarization film (PL1) and the second planarization film (PL2), and the light that has been totally reflected is reflected by the cathode electrode (CAT) and emitted downwards.

[0080] In this structure, the etched side surface of the second planarization film (PL2) has a relatively gentle inclination angle of 50 to 70 degrees. The light-emitting layer (EL) has a structure that connects two adjacent pixels. For example, in a structure where a first light-emitting diode (OLE1) is located in the first pixel and a second light-emitting diode (OLE2) is located in the second pixel and they are adjacent to each other, the light-emitting layer (EL) has a structure that is stacked while connecting the first light-emitting diode (OLE1) and the second light-emitting diode (OLE2). Because the etched inclined surface of the second planarization film (PL2) has a gentle inclination angle, the light-emitting layer (EL) has a structure that connects the first light-emitting diode (OLE1) and the second light-emitting diode (OLE2) with a nearly uniform thickness.

[0081] Therefore, leakage current can flow horizontally along the light-emitting layer (EL), i.e., in the X-axis direction, which can cause the light-emitting diode (OEL) of an undesired pixel to be driven. In the first embodiment of this disclosure, a structure is presented to prevent such a problem caused by horizontal leakage current.

[0082] Referring to Figure 6, a second planarization film (PL2) is further arranged in an island-like manner between the first light-emitting diode (OLE1) and the second light-emitting diode (OLE2). In addition, dummy anode electrodes (DAN) are arranged in an island-like manner on the upper surface of the second planarization film (PL2).

[0083] As shown in Figure 6, the path is lengthened by the intermediate structure connecting the first light-emitting diode (OLE1) to the second light-emitting diode (OLE2) in the light-emitting layer (EL). As a result, the path for horizontal leakage current to move from the first light-emitting diode (OLE1) to the second light-emitting diode (OLE2) is also lengthened, thus suppressing horizontal leakage current.

[0084] However, under conditions where the tilt angle of the second planarization layer (PL2) is gentle, around 50 degrees, it is not possible to completely suppress horizontal leakage current. In particular, when the resolution of the light-emitting display device is 400 PPI (pixels per inch) or higher and configured at ultra-high density, or in small light-emitting display devices of 10 inches or less, the spacing between pixels becomes narrow, and horizontal leakage current can easily occur.

[0085] The following describes a structure for a light-emitting display device that can further prevent problems that may occur in the first embodiment. [Examples]

[0086] The structure of the light-emitting device according to the second embodiment of this disclosure will be described below with reference to Figure 7. Figure 7 is an enlarged cross-sectional view showing the structure of the light-emitting device according to the second embodiment of this disclosure, cut along line II-II' in Figure 3.

[0087] Referring to Figure 7, the first light-emitting diode (OLE1) and the second light-emitting diode (OLE2) are arranged adjacent to each other. Between the first light-emitting diode (OLE1) and the second light-emitting diode (OLE2), the second planarization film (PL2) is completely removed, and the first planarization film (PL1) is exposed. Furthermore, the first planarization film (PL1) is etched to a certain depth to form trenches (TR).

[0088] A dummy anode electrode (DAN) is formed on the first planarization film (PL1) exposed between the first light-emitting diode (OLE1) and the second light-emitting diode (OLE2). The dummy anode electrode (DAN) is physically and electrically isolated from the first anode electrode (ANO1) and the second anode electrode (ANO2). When viewed from the surface of the display device, the dummy anode electrode (DAN) is positioned between the pixel rows and can have a linear segment shape that extends long along the Y-axis in the plane of the display device. Therefore, in some cases, the dummy anode electrode (DAN) can be used as wiring that supplies a separate electrical signal different from that of the anode electrode (ANO).

[0089] The first anode electrode (ANO1) of the first light-emitting diode (OLE1) and the second anode electrode (ANO2) of the second light-emitting diode (OLE2) are positioned on the upper surface of the second planarization film (PL2). Meanwhile, the dummy anode electrode (DAN) is positioned on the upper surface of the first planarization film (PL1) exposed between the first light-emitting diode (OLE1) and the second light-emitting diode (OLE2). Using the first anode electrode (ANO1), the second anode electrode (ANO2), and the dummy anode electrode (DAN) as masks, the first planarization film (PL1) can be further etched to form trenches (TR) of a certain depth. Since the second planarization film (PL2) is made of a different material from the first planarization film (PL1), when the first planarization film (PL1) is patterned to form trenches (TR), the second planarization film (PL2) is not etched, and the sidewall inclination does not deform to more than 70 degrees. Therefore, problems such as pixel shrinkage do not occur.

[0090] Furthermore, the first planarization film (PL1) can be over-etched to form trenches (TR) with a steep inclination angle (δ) of 70 degrees or more. That is, the inclination angle (θ) of the etched sidewalls of the second planarization film (PL2) has a gentle inclination of 50 to 70 degrees. On the other hand, the inclination angle (δ) of the etched sidewalls generated while forming trenches (TR) in the first planarization film (PL1) has a steep inclination angle of 70 to 90 degrees.

[0091] As a result, the light-emitting layer (EL) deposited on the surface of the substrate 110 where the trench (TR) is formed has its connectivity interrupted by the trench (TR). Therefore, leakage current is not transmitted to adjacent light-emitting diodes arranged in the horizontally adjacent pixels along the light-emitting layer (EL), and pixel malfunction can be prevented. In other words, the light-emitting layer (EL) is formed on the first light-emitting diode (OLE1) and the second light-emitting diode (OLE2), respectively, and a dummy light-emitting layer (DEL) with interrupted connectivity can be stacked on the dummy anode electrode (DAN).

[0092] A cathode electrode (CAT) is laminated on the light-emitting layer (EL) and the dummy light-emitting layer (DEL). The cathode electrode (CAT) is a metallic inorganic material. Therefore, even in areas where the connectivity of the light-emitting layer (EL) is interrupted, the cathode electrode (CAT) can be deposited while maintaining connectivity.

[0093] In the second embodiment of the present disclosure, the light-emitting display device has a structure in which the second planarization film (PL2) is formed in an island shape, and the cathode electrode (CAT) is equipped with a micromirror, which can extract light that may be extinguished inside the anode electrode (ANO) to the outside, thereby increasing the light extraction efficiency. Furthermore, trenches (TR) placed between adjacent pixels prevent horizontal leakage current, thereby preventing pixel malfunction and improving color purity.

[0094] In the light-emitting device according to the second embodiment, two trenches (TR) are positioned between the first anode electrode (ANO1) of the first light-emitting diode (OLE1) and the second anode electrode (ANO2) of the second light-emitting diode (OLE2). Between the two trenches (TR), a dummy anode electrode (DAN) is positioned on the upper surface of the first planarization film (PL1) at a height higher than the trenches (TR). Therefore, one trench (TR) is positioned between the dummy anode electrode (DAN) and the first anode electrode (ANO1). Similarly, one different trench (TR) is positioned between the dummy anode electrode (DAN) and the second anode electrode (ANO2). [Examples]

[0095] A third embodiment of the present disclosure will be described below with reference to Figure 8. Figure 8 is an enlarged cross-sectional view showing the structure of a light-emitting device according to the third embodiment of the present disclosure, cut along line II-II' in Figure 3.

[0096] Referring to Figure 8, the basic structure is the same as that of the light-emitting device according to the second embodiment shown in Figure 7. The difference is that in the third embodiment, the depth of the trench (TR) is the same as the thickness of the first planarization film (PL1). That is, the trench (TR) is formed by completely removing the first planarization film (PL1) that is exposed between the dummy anode electrode (DAN) and the second planarization film (PL2).

[0097] The first anode electrode (ANO1) of the first light-emitting diode (OLE1) and the second anode electrode (ANO2) of the second light-emitting diode (OLE2) are positioned on the upper surface of the second planarization film (PL2). Meanwhile, the dummy anode electrode (DAN) is positioned on the upper surface of the first planarization film (PL1) exposed between the first light-emitting diode (OLE1) and the second light-emitting diode (OLE2). Using the first anode electrode (ANO1), the second anode electrode (ANO2), and the dummy anode electrode (DAN) as a mask, the first planarization film (PL1) can be completely removed, and a trench (TR) having a depth corresponding to the thickness of the first planarization film (PL1) can be formed. Since the second planarization film (PL2) is made of a different material from the first planarization film (PL1), when the first planarization film (PL1) is patterned to form the trench (TR), the second planarization film (PL2) is not etched, and the side wall inclination does not deform to more than 70 degrees. Therefore, problems such as pixel reduction do not occur.

[0098] By forming trenches (TR) to a greater depth in this manner, an over-etching process can be performed, resulting in a longer etching time for the first planarization film (PL1). Therefore, the angle (δ) of the sidewalls of the trenches (TR), i.e., the inclination angle of the etched sidewalls of the first planarization film (PL1), is formed to have a steep inclination angle of 70 degrees or more. As a result, the light-emitting layer (EL) deposited on the surface of the substrate 110 on which the trenches (TR) are formed is disconnected by the trenches (TR). Therefore, leakage current is not transmitted to adjacent light-emitting diodes arranged in the horizontal direction along the light-emitting layer (EL) to adjacent pixels, thus preventing pixel malfunction. In other words, the light-emitting layer (EL) is formed on the first light-emitting diode (OLE1) and the second light-emitting diode (OLE2), respectively, and a dummy light-emitting layer (DEL) with disconnected connectivity can be stacked on the dummy anode electrode (DAN).

[0099] Cathode electrodes (CATs) are laminated on the light-emitting layer (EL) and the dummy light-emitting layer (DEL). The cathode electrodes (CATs) are made of metallic inorganic material. Therefore, even in areas where the connectivity of the light-emitting layer (EL) is interrupted, the cathode electrodes (CATs) can be deposited while maintaining their connectivity.

[0100] In the third embodiment of the present disclosure, the light-emitting device has a structure in which the second planarization film (PL2) is formed in an island shape, and the cathode electrode (CAT) is equipped with a micromirror, which can extract light that may be extinguished inside the anode electrode (ANO) to the outside, thereby increasing the light extraction efficiency. Furthermore, trenches (TR) placed between adjacent pixels prevent horizontal leakage current, thereby preventing pixel malfunction and improving color purity. [Examples]

[0101] A fourth embodiment of the present disclosure will be described below with reference to Figure 9. Figure 9 is an enlarged cross-sectional view showing the structure of a light-emitting device according to the fourth embodiment of the present disclosure, cut along line II-II' in Figure 3.

[0102] Referring to Figure 9, the basic structure is the same as that of the light-emitting device according to the second embodiment shown in Figure 7. However, the fourth embodiment differs in that it has two trenches (TR). That is, the trenches (TR) have a structure in which a first trench (TR1) and a second trench (TR2) are arranged consecutively between the dummy anode electrode (DAN) and the anode electrode (ANO). Two trenches (TR1, TR2) can be arranged on each side of the dummy anode electrode (ANO). Also, a dummy anode electrode (DAN) can be arranged between the first trench (TR1) and the second trench (TR2).

[0103] In the fourth embodiment of the light-emitting device, four trenches (TR) are positioned between the first anode electrode (ANO1) of the first light-emitting diode (OLE1) and the second anode electrode (ANO2) of the second light-emitting diode (OLE2). Between each trench (TR), a dummy anode electrode (DAN) is positioned on the upper surface of the first planarization film (PL1), which is located at a height higher than the trenches (TR).

[0104] This is not the only option; various numbers of trenches can be placed between two adjacent anode electrodes (ANOs) in the horizontal (X-axis) direction. For example, three, five, or six trenches can be placed between two anode electrodes (ANOs). In this case, a dummy anode electrode (DAN) can be placed between each trench.

[0105] As the number of trenches (TRs) increases, the path of the light-emitting layer (EL) stacked on top of them becomes longer, and the trenches (TRs) can more reliably ensure the isolation of the light-emitting layer (EL). Therefore, horizontal leakage current can be prevented without forming deep trenches (TRs) as in the third embodiment.

[0106] The structure according to the fourth embodiment, in which there are three or more trenches (TR) between two adjacent anode electrodes (ANOs), can be applied to low-resolution display devices with a relatively wide pixel spacing of 100 PPI (pixels per inch) or less. Alternatively, the structure according to the fourth embodiment can be applied to large-area display devices of 50 inches or more, which have a large display area and a relatively wide pixel spacing, even if they have high resolution.

[0107] In the fourth embodiment of the present disclosure, the light-emitting device has a structure in which the second planarization film (PL2) is formed in an island shape, and the cathode electrode (CAT) is equipped with a micromirror, which can extract light that may be extinguished inside the anode electrode (ANO) to the outside, thereby increasing the light extraction efficiency. Furthermore, trenches (TR1, TR2) placed between adjacent pixels can prevent horizontal leakage current, thereby preventing pixel malfunction and improving color purity. [Examples]

[0108] A fifth embodiment of the present disclosure will be described below with reference to Figure 10. Figure 10 is a plan view showing the structure of a light-emitting device according to the fifth embodiment of the present disclosure.

[0109] Referring to Figure 10, the light-emitting device according to the fifth embodiment of this disclosure has substantially the same structure as the light-emitting device shown in Figure 1. Therefore, the descriptions of the same components will be briefly explained or omitted, and the main components will be explained in detail. Figure 10 further shows the low-voltage wiring (VSS), a component that was omitted in Figure 1. Also in Figure 10, the dummy anode electrode (DAN), a component that has been further added to the light-emitting device according to this disclosure.

[0110] Low-voltage wiring (VSS) is located in the non-display area (NDA) surrounding the display area (AA). For example, it can be located on the left, top, and right sides of the display area (AA), enclosing the display area (AA) in an "∩" shape. Low-voltage wiring (VSS) can be connected to a pad portion 300 located in the lower non-display area (NDA) of the display area (AA), and can be connected to a timing control unit 500 via a flexible wiring film 430. The timing control unit 500 can supply low-voltage signals to the low-voltage wiring (VSS). Low-voltage wiring (VSS) can be connected to pixels (P) located in the display area (AA). For example, it can be connected to the cathode electrode (CAT) of a light-emitting diode (OLE) as described in Figures 2 to 4.

[0111] According to the first to fourth embodiments of this specification, the light-emitting display device according to the present disclosure comprises a dummy anode electrode (DAN) disposed on a second planarization film (PL2) arranged in an island-like manner between two adjacent pixel rows. In particular, in the second embodiment shown in Figure 7, the dummy anode electrode (DAN) is disposed between two trenches (TR) arranged between pixel rows.

[0112] The dummy anode electrode (DAN) is positioned between two adjacent pixel rows, and therefore, as in Figure 10, it is arranged in a linear shape along the vertical (Y-axis) direction in the display area (AA). Since the dummy anode electrode (DAN) is made of the same material as the anode electrode (ANO), it consists of a transparent conductive material. Therefore, the dummy anode electrode (DAN) can be used as a component for transmitting electrical signals.

[0113] As an example, a dummy anode electrode (DAN) can be connected to a low-potential wiring (VSS) positioned on the upper edge of the display area (AA) and used as auxiliary low-potential wiring. As explained with reference to Figures 6 to 11, a cathode electrode (CAT) is stacked on the dummy anode electrode (DAN). The cathode electrode (CAT) is the electrode that receives the base voltage applied to drive the light-emitting diode (OLE), and it is necessary to always maintain a stable and constant low potential. Therefore, the dummy anode electrode (DAN), which is in surface contact with the cathode electrode (CAT), can be connected to the low-potential wiring (VSS) to configure the system to always maintain a constant low potential for the cathode electrode (CAT).

[0114] An example of a light-emitting display device according to this disclosure includes a substrate, a driving element layer, a first planarization film, a second planarization film, an anode electrode, a light-emitting layer, and a cathode electrode. The substrate comprises a plurality of pixels. The driving element layer is disposed on the substrate. The first planarization film covers the driving element layer. The second planarization film is disposed within each pixel on the first planarization film. The anode electrode is disposed on the upper surface of the second planarization film. The light-emitting layer is disposed on the first planarization film, the second planarization film, and the anode electrode. The cathode electrode is disposed on the light-emitting layer.

[0115] In summary, embodiments of the light-emitting device according to the present disclosure can improve light extraction efficiency by configuring a micromirror structure formed by cathode electrodes on island-shaped planarized films. Such a structure guides light that could be lost by total internal reflection towards the substrate, thereby improving brightness. Furthermore, the light-emitting device according to the present disclosure can reduce light loss and improve luminous efficiency by using a structure in which insulating layers with different refractive indices are stacked, that is, by arranging materials so that light is transmitted from the anode electrode with a high refractive index to the planarized film with a low refractive index.

[0116] In particular, to prevent lateral leakage current and improve color purity in high-resolution or small display devices, trenches and dummy anode electrodes are provided between adjacent pixels. These structural features prevent the light-emitting layer from having continuity between pixels, allowing the light-emitting layer to have a structure separated from each pixel. Furthermore, the sidewalls of the planarization film can be positioned with an inclination angle of 50 to 75 degrees to optimize the direction in which light is extracted. Such a structure and material arrangement can be expected to provide advantages such as improved display device performance, pixel separation, and the provision of an improved display device.

[0117] For example, the anode electrode includes either a transparent conductive material or a semi-permeable metallic material. The cathode electrode includes a metallic material.

[0118] As an example, the light-emitting layer is laminated while covering the upper surface of the first planarization film, the sidewall of the second planarization film, the edge of the upper surface of the second planarization film, and the upper surface of the anode electrode. The cathode electrode is laminated in surface contact with the surface of the light-emitting layer.

[0119] For example, the second planarization film has a refractive index up to 0.2 lower than the refractive index of the anode electrode. The first planarization film has a refractive index at least 0.5 lower than the refractive index of the second planarization film.

[0120] For example, the refractive index of the anode electrode is 2.0 to 2.3. The refractive index of the second planarization film is 1.8 to 2.0. The refractive index of the first planarization film is 1.3 to 1.5.

[0121] As an example, the substrate further includes adjacent first and second pixels among a plurality of pixels, a first light-emitting diode placed in the first pixel, a second light-emitting diode placed in the second pixel, and a dummy anode electrode placed between the first light-emitting diode and the second light-emitting diode.

[0122] As an example, the device further includes at least one trench positioned between the first light-emitting diode and the second light-emitting diode.

[0123] For example, the trench is recessed from the upper surface of the first planarization film to a certain position inside the first planarization film.

[0124] For example, the trench is recessed from the top surface of the first planarization membrane to the bottom surface of the first planarization membrane.

[0125] For example, trenches are arranged in a sequence of 2 to 4 between the first and second light-emitting diodes.

[0126] As an example, in the light-emitting layer, the connection between the first light-emitting diode and the second light-emitting diode is broken by a trench.

[0127] As an example, the first light-emitting diode includes a second planarization film disposed on the first planarization film, a first anode electrode disposed on the second planarization film, a light-emitting layer disposed on the first anode electrode, and a cathode electrode disposed on the light-emitting layer. The second light-emitting diode includes a second planarization film disposed on the first planarization film, a second anode electrode disposed on the second planarization film, a light-emitting layer disposed on the second anode electrode, and a cathode electrode disposed on the light-emitting layer. It further includes a trench recessed into the first planarization film between the first light-emitting diode and the dummy anode electrode.

[0128] As an example, the trench includes a first trench and a second trench positioned adjacent to each other between the first light-emitting diode and the dummy anode electrode.

[0129] As an example, the substrate further includes a display area on which multiple pixels are arranged, a non-display area surrounding the display area, and low-potential wiring arranged in the non-display area. Dummy anode electrodes are connected to the low-potential wiring.

[0130] Furthermore, an embodiment of the present invention includes a substrate, a driving element layer, a first planarization film, a second planarization film, an anode electrode, a light-emitting layer, and a cathode electrode. Multiple pixels are arranged on the substrate. The driving element layer is arranged on the substrate. The first planarization film is arranged on the driving element layer. The second planarization film protrudes in an island-like manner on the first planarization film. The anode electrode is arranged on the second planarization film. The light-emitting layer is arranged on the first planarization film, the sidewalls of the second planarization film not covered by the anode electrode, and the anode electrode. The cathode electrode is arranged on the light-emitting layer. The anode electrode contains a transparent conductive material. The refractive index of the second planarization film is up to 0.2 lower than the refractive index of the anode electrode.

[0131] As an example, the light-emitting layer is further positioned in the edge region of the upper surface of the second planarization film that is not covered by the anode electrode.

[0132] For example, the refractive index of the first planarization film is at least 0.5 lower than the refractive index of the second planarization film.

[0133] For example, the inclination angle of the sidewall of the second planarization film is 40 to 80 degrees with respect to the horizontal surface.

[0134] For example, the inclination angle of the sidewall of the second planarization film is 50 to 75 degrees with respect to the horizontal surface.

[0135] The features, structures, and effects described in the examples of this disclosure described above are included in, and not necessarily limited to, at least one of the examples of this disclosure. Furthermore, the features, structures, and effects exemplified in at least one example of this disclosure can be combined or modified and implemented in other examples by a person with ordinary skill in the art to which this disclosure belongs. Accordingly, content related to such combinations and modifications should be construed as being included in the scope of this disclosure.

[0136] The Disclosure described above is not limited to the embodiments and accompanying figures described above, and it will be apparent to a person ordinary in the art to which this Disclosure pertains that various substitutions, modifications, and alterations are possible without departing from the technical matters of this Disclosure. Accordingly, the scope of this Disclosure is indicated by the claims set forth below, and all modified or altered forms derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included within the scope of this Disclosure. [Explanation of symbols]

[0137] 110 circuit boards PL1 1st planarization film PL2 2nd planarization film EL light-emitting layer ANO Anode electrode CAT cathode electrode

Claims

1. A substrate on which multiple pixels are arranged, A driving element layer disposed on the substrate, A first planarization film covering the aforementioned drive element layer, A second planarization film is disposed within each pixel on the first planarization film, an anode electrode positioned on the upper surface of the second planarized film, The first planarization film, the second planarization film, and the light-emitting layer disposed on the anode electrode, A light-emitting display device, comprising a cathode electrode disposed on the light-emitting layer.

2. The anode electrode is It comprises either a transparent conductive material or a semi-permeable metallic material, The cathode electrode is The light-emitting display device according to claim 1, comprising an opaque metallic substance.

3. The aforementioned light-emitting layer The first planarization film is laminated while covering the upper surface, the side wall of the second planarization film, the edge of the upper surface of the second planarization film, and the upper surface of the anode electrode. The cathode electrode is The light-emitting device according to claim 1, wherein the light-emitting layer is laminated in surface contact with the surface of the light-emitting layer.

4. The second planarization film is Having a refractive index up to 0.2 lower than the refractive index of the anode electrode, The first planarized film is The light-emitting device according to claim 1, having a refractive index at least 0.5 lower than the refractive index of the second planarization film.

5. The refractive index of the anode electrode is 2.0 to 2.

3. The refractive index of the second planarization film is 1.8 to 2.

0. The light-emitting device according to claim 4, wherein the refractive index of the first planarization film is 1.3 to 1.

5.

6. The aforementioned substrate, Among the plurality of pixels, adjacent first and second pixels, The first light-emitting diode arranged in the aforementioned pixel, A second light-emitting diode arranged in the second pixel, The light-emitting device according to claim 1, further comprising a dummy anode electrode disposed between the first light-emitting diode and the second light-emitting diode.

7. The light-emitting device according to claim 6, further comprising at least one trench disposed between the first light-emitting diode and the second light-emitting diode.

8. The light-emitting device according to claim 7, wherein at least one trench is recessed from the upper surface of the first planarized film to a certain position inside the first planarized film.

9. The light-emitting device according to claim 7, wherein at least one trench is recessed from the upper surface of the first planarized film to the bottom surface of the first planarized film.

10. The at least one trench, The light-emitting device according to claim 7, wherein two to four light-emitting diodes are arranged in a continuous manner between the first light-emitting diode and the second light-emitting diode.

11. The aforementioned light-emitting layer The light-emitting device according to claim 7, wherein the trench disconnects the connection between the first light-emitting diode and the second light-emitting diode.

12. The first light-emitting diode, The second planarization film is disposed on the first planarization film, A first anode electrode disposed on the second planarization film, The light-emitting layer disposed on the first anode electrode described above, The cathode electrode is disposed on the light-emitting layer, The second light-emitting diode is The second planarization film is disposed on the first planarization film, A second anode electrode disposed on the second planarization film, A light-emitting layer placed on the aforementioned second anode electrode, The cathode electrode is disposed on the light-emitting layer, The light-emitting device according to claim 6, further comprising at least one trench recessed into the interior of the first planarization film between the first light-emitting diode and the dummy anode electrode.

13. The at least one trench, The light-emitting device according to claim 12, further comprising a first trench and a second trench disposed adjacent to each other between the first light-emitting diode and the dummy anode electrode.

14. The aforementioned substrate, A display area in which the plurality of pixels are arranged, A non-display area arranged around the aforementioned display area, The system further includes low-potential wiring arranged in the non-display area, The light-emitting display device according to claim 6, wherein the dummy anode electrode is connected to the low-potential wiring.

15. A substrate having multiple pixels, A driving element layer disposed on the substrate, A first planarization film disposed on the aforementioned drive element layer, A second planarization film protruding in an island-like manner on the first planarization film, an anode electrode placed on the second planarization film, The first planarization film, the sidewall of the second planarization film not covered by the anode electrode, and the light-emitting layer disposed on the anode electrode, The cathode electrode is disposed on the light-emitting layer, The anode electrode contains a transparent conductive material, A light-emitting display device wherein the refractive index of the second planarization film is up to 0.2 lower than the refractive index of the anode electrode.

16. The light-emitting device according to claim 15, wherein the light-emitting layer is further disposed in the edge region of the upper surface of the second planarization film that is not covered by the anode electrode.

17. The light-emitting device according to claim 16, wherein the refractive index of the first planarization film is at least 0.5 lower than the refractive index of the second planarization film.

18. The light-emitting device according to claim 15, wherein the inclination angle of the side wall of the second planarization film is 40 to 80 degrees with respect to the horizontal plane.

19. The light-emitting device according to claim 15, wherein the inclination angle of the side wall of the second planarization film is 50 to 75 degrees with respect to the horizontal plane.

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