Organic electroluminescent device

Abstract

This application relates to organic electroluminescent devices. The invention provides an organic electroluminescent device comprising a device with a unique out-coupling design, wherein the out-coupling layer comprises an array of nanoparticles. The array of nanoparticles is arranged in a quasi-periodic array. The quasi-periodic array of nanoparticles makes the spacing of the nanoparticles more random, thereby enhancing device efficiency, and enables tunability of the emission profile by tuning the symmetry of the array of nanoparticles within the out-coupling layer.

Description

[0001] Cross-reference of related applications

[0002] This application claims priority to U.S. Patent Application Serial No. 63 / 730,775, filed December 11, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to an emitting device, including an organic emitting device having a plurality of sub-pixels that can be stacked in the same device, and also to a technique for manufacturing the emitting device. Background Technology

[0004] For many reasons, optoelectronic devices utilizing organic materials are becoming increasingly popular. Many of the materials used to manufacture these devices are relatively inexpensive, thus organic optoelectronic devices have the potential to offer a cost advantage over inorganic devices. Furthermore, the inherent properties of organic materials, such as their flexibility, make them more suitable for specific applications, such as fabrication on flexible substrates. Examples of organic optoelectronic devices include organic light-emitting diodes / devices (OLEDs), organic phototransistors, organic photovoltaic cells, and organic photodetectors. For OLEDs, organic materials can exhibit performance advantages over conventional materials. For instance, the wavelength of light emitted by an organic emitting layer can often be easily tuned using appropriate dopants.

[0005] OLEDs utilize organic thin films that emit light when a voltage is applied to the device. OLEDs are becoming an increasingly popular technology for applications such as flat panel displays, lighting, and backlighting. Several OLED materials and configurations are described in U.S. Patent Nos. 5,844,363, 6,303,238, and 5,707,745, which are incorporated herein by reference in their entirety.

[0006] One application of phosphorescent molecules enabling phosphorescence is in full-color displays. Industry standards for such displays require pixels suited to emit specific colors (called "saturated" colors). Specifically, these standards require pixels saturated with red, green, and blue light. Alternatively, OLEDs can be designed to emit white light. In conventional LCDs, absorption filters are used to filter the emission from a white backlight to produce red, green, and blue emission. The same technology can be used for OLEDs. White OLEDs can be a single EML device or a stacked structure. Color can be measured using CIE coordinates, well-known in the field.

[0007] As used herein, the term "organic" includes both polymeric materials and small-molecule organic materials that can be used to manufacture organic optoelectronic devices. "Small molecule" refers to any organic material that is not a polymer, and "small molecule" can actually be quite large. In some cases, small molecules may include repeating units. For example, using long-chain alkyl groups as substituents does not remove the molecule from the "small molecule" category. Small molecules can also be incorporated into polymers, for example, as side groups on the polymer backbone or as part of the backbone. Small molecules can also serve as the core portion of dendritic polymers, which consist of a series of chemical shells built upon the core portion. The core portion of a dendritic polymer can be a fluorescent or phosphorescent small-molecule emitter. Dendritic polymers can be "small molecules," and all dendritic polymers currently used in the OLED field are considered small molecules.

[0008] As used herein, "top" means furthest from the substrate, and "bottom" means closest to the substrate. When the first layer is described as being "placed" "above" the second layer, the first layer is placed further away from the substrate. Unless specified that the first layer "contacts" the second layer, other layers may exist between the first and second layers. For example, even if various organic layers exist between the cathode and anode, the cathode may still be described as being "placed" "above" the anode.

[0009] As used herein, “solution-handleable” means capable of dissolving, dispersing or transporting in and / or depositing from a liquid medium in the form of a solution or suspension.

[0010] When a ligand is considered to directly contribute to the photosensitivity of the emissive material, the ligand may be referred to as "photosensitive." When a ligand is considered not to contribute to the photosensitivity of the emissive material, the ligand may be referred to as "auxiliary," but auxiliary ligands can alter the properties of photosensitizing ligands.

[0011] As used herein, and as will generally be understood by those skilled in the art, if the first energy level is closer to the vacuum level, then the first "Highest Occupied Molecular Orbital" (HOMO) or "Lowest Unoccupied Molecular Orbital" (LUMO) level is "greater than" or "higher than" the second HOMO or LUMO level. Since the ionization potential (IP) is measured as a negative energy relative to the vacuum level, a higher HOMO level corresponds to an IP with a smaller absolute value (less negative IP). Similarly, a higher LUMO level corresponds to an electron affinity (EA) with a smaller absolute value (less negative EA). On a conventional energy level diagram with the vacuum level at the top, the LUMO levels of a material are higher than the HOMO levels of the same material. A "higher" HOMO or LUMO level appears to be closer to the top of this diagram than a "lower" HOMO or LUMO level.

[0012] As used herein, and as will generally be understood by those skilled in the art, if the first work function has a higher absolute value, then the first work function is “greater” or “higher” than the second work function. This is because the work function is typically measured as a negative number relative to the vacuum level, meaning that the “higher” work function is more negative. On a conventional energy level diagram with the vacuum level at the top, the “higher” work function is illustrated as being farther from the vacuum level in the downward direction. Therefore, the definitions of HOMO and LUMO levels follow different rules than those for the work function.

[0013] This document may describe layers, materials, regions, and devices by referring to the color of light emitted. Generally, as used herein, an emitting region that produces light of a particular color may include one or more emitting layers arranged in a stacked manner on top of each other.

[0014] As used herein, a "red" layer, material, region, or device refers to a layer, material, region, or device that emits light or whose emission spectrum has a peak in the range of approximately 580–700 nm. Similarly, a "green" layer, material, region, or device refers to a layer, material, region, or device that emits or has an emission spectrum with a peak wavelength in the range of approximately 500–600 nm; a "blue" layer, material, or device refers to a layer, material, or device that emits or has an emission spectrum with a peak wavelength in the range of approximately 400–500 nm; a "yellow" layer, material, region, or device refers to a layer, material, region, or device with an emission spectrum with a peak wavelength in the range of approximately 540–600 nm; a "cyan" layer, material, or device refers to a layer, material, or device that emits or has an emission spectrum with a peak wavelength in the range of approximately 490–520 nm; and an "orange" layer, material, or device refers to a layer, material, or device that emits or has an emission spectrum with a peak wavelength in the range of approximately 570–620 nm. In some arrangements, individual regions, layers, materials, areas, or devices can provide separate “deep blue” and “light blue” light. As used herein, in arrangements providing separate “light blue” and “deep blue” components, the “deep blue” component refers to the component whose peak emission wavelength is at least about 4 nm smaller than the peak emission wavelength of the “light blue” component. Typically, the peak emission wavelength of the “light blue” component is in the range of about 465 nm to 500 nm, and the peak emission wavelength of the “deep blue” or “dark blue” component is in the range of about 400 nm to 470 nm, but these ranges can vary for some configurations. The peak emission wavelength of the “light green” component is in the range of about 520–560 nm, and the peak emission wavelength of the “deep green” or “dark green” component is in the range of about 500–520 nm, but these ranges can vary for some configurations. The peak emission wavelength of the near infrared (NIR) component is in the range of about 700–1800 nm. Similarly, a color-changing layer refers to a layer that converts or modifies light of another color into light having a wavelength specified for said color. For example, a "red" color filter refers to a color filter that forms light with wavelengths in the range of approximately 580-700 nm. Generally, there are two types of color-changing layers: color filters that modify the spectrum by removing unwanted wavelengths of light, and color-changing layers that convert higher-energy photons into lower-energy ones. A "color" component refers to a component of light that, when activated or used, produces or otherwise emits light of a specific color as described above. For example, "a first emission region of a first color" and "a second emission region of a second color different from the first color" describe two emission regions that emit two different colors as described above when activated within the device.

[0015] As used herein, emitting materials, layers, and regions can be distinguished from each other and from other structures based on the spectrum initially generated by the material, layer, or region, rather than by the light ultimately emitted by the same or different structures. Initial light generation is typically a result of energy level changes that lead to photon emission. For example, an organic emitting material may initially generate blue light, which can be converted into red or green light by a color filter, quantum dot, or other structure, causing the entire emitting stack or subpixel to emit red or green light. In this case, the initial emitting material or layer may be referred to as the "blue" component, even if the subpixel is the "red" or "green" component.

[0016] In some cases, the color of components, such as the color of emitting regions, subpixels, color-changing layers, etc., can preferably be described according to 1931 CIE coordinates. For example, a yellow emitting material may have multiple peak emission wavelengths, one in or near the edge of the "green" region and one in or near the edge of the "red" region, as previously described. Therefore, as used herein, each color item also corresponds to a shape in the 1931 CIE coordinate color space. The shape in the 1931 CIE color space is constructed by following the trajectory between two color points and any other interior points. For example, the interior shape parameters for red, green, blue, and yellow can be defined as follows:

[0017]

[0018] Further details about OLEDs and the definitions described above can be found in U.S. Patent No. 7,279,704, which is incorporated herein by reference in its entirety. Summary of the Invention

[0019] According to one embodiment, an organic light-emitting diode / device (OLED) is also provided. The OLED may include an anode, a cathode, and an organic layer disposed between the anode and the cathode. According to one embodiment, the organic light-emitting device is incorporated into one or more devices selected from consumer products, electronic component modules, and / or lighting panels.

[0020] An organic emission device is provided, comprising: a substrate; a first electrode; an emission layer comprising an organic emission material disposed above the first electrode; a reinforcement layer disposed above the emission layer; and an excoupling layer disposed above the reinforcement layer, wherein the excoupling layer comprises a nanoparticle array, wherein the nanoparticle array is a periodic array or a quasi-periodic array.

[0021] The reinforcement layer may be a second electrode within an organic emission device. Alternatively, the device may include a second electrode in addition to the reinforcement layer. In one embodiment, the second electrode, separate from the reinforcement layer, may be disposed above the emission layer and may be an optically transparent material, a metallic material, or a non-metallic material. In one embodiment, the reinforcement layer may be disposed above the second electrode, and the bottom surface of the reinforcement layer may contact the top surface of the second electrode. In one embodiment, the second electrode may be disposed above the reinforcement layer.

[0022] The enhancement layer may include a plasmonic material exhibiting surface plasmon resonance, which is nonradiatively coupled to an organic emitting material in the emission layer and transfers excited-state energy from the organic emitting material to the nonradiative mode of the surface plasmon polaritons. The enhancement layer may be configured to be located at a distance from the organic emitting material not exceeding a threshold distance. The organic emitting material may possess both a total nonradiative decay rate constant and a total radiative decay rate constant due to the presence of the enhancement layer. The threshold distance may be a distance where the total nonradiative decay rate constant is equal to the total radiative decay rate constant. The organic emitting material may possess a total nonradiative decay rate constant. Total radiation attenuation constant The total nonradiative attenuation rate constant attributed to the enhancement layer and the total radiation attenuation rate constant attributed to the enhancement layer The threshold distance is the distance that meets the following conditions: .

[0023] The emission profile of the device can be tuned based on the choice of array symmetry in the quasi-periodic array design. Each nanoparticle in the array can include multiple nanoparticles. Array symmetry can be rotational symmetry, translational symmetry, etc. A quasi-periodic array can be an array design that does not have long-range positional order and where the length scale of short-range positional periodicity is no greater than the plasmon propagation length of the reinforcement layer. In other words, a quasi-periodic array is not a highly ordered array. The interparticle spacing (edge-to-edge spacing between adjacent nanoparticles, where the edge is the closest edge between adjacent nanoparticles) within the quasi-periodic array can be greater than the maximum size of the nanoparticles; for example, the interparticle spacing can be at least 200 nm, at least 300 nm, at least 400 nm, at least 500 nm, etc. The lattice period of the quasi-periodic array can be at least 100 nm, at least 200 nm, at least 300 nm, at least 400 nm, greater than 500 nm, etc.

[0024] Quasi-periodic arrays can be generated by combining the particle distributions of a first periodic array and a second periodic array, wherein the first and second periodic arrays have different lattice orders or periodicities, such as square lattices, hexagonal lattices, tilted lattices, rectangular lattices, etc. In an embodiment where a group of nanoparticles forming a square array is arranged in a hexagonal array, the number of nanoparticles in each group of the square array can be even, such as 4, 6, 8, etc. In another embodiment, a group of nanoparticles forming a hexagonal array can be assembled into a square lattice.

[0025] Compared to arrays formed through embedding methods, quasi-periodic arrays can be higher-order arrays with increased rotational and / or translational symmetries. Higher-order arrays can be generated using a mathematical method called the cut and project method, where an n-dimensional lattice array is projected onto a two-dimensional plane to create a tessellation pattern. Nanoparticles can be placed at the vertices of the tessellation pattern to produce even higher-order quasi-periodic arrays. For example, the projection of a 5-dimensional cubic lattice onto a two-dimensional plane forms a Penrose tessellation pattern and a Penrose nanoparticle array with fivefold rotational symmetry. To increase the order of the array, the dimensions of a higher-dimensional lattice can be added and then projected onto a two-dimensional plane.

[0026] The nanoparticle array in the decoupling layer can exhibit the Moiré effect. This array, referred to as a Moiré array for ease of understanding, can be formed by superimposing multiple arrays with different lattice symmetries or periodicities by changing their relative lattice orientations. The first and second periodic arrays can be rotated relative to each other. The rotation angle can be 5°, 30°, 45°, etc. The rotation angle can be selected to tune the radiation pattern and emission direction of the device. Quasi-periodic arrays can also be formed by stacking additional periodic arrays with the first and second periodic arrays and stacking them in the out-of-plane direction. Each of these arrays can be separated by a distance of at least 10 nm, at least 25 nm, at least 50 nm, less than 100 nm, etc., in the out-of-plane direction. The periodicity of each of these arrays can be different from the other periodic arrays.

[0027] The first and second periodic arrays can be placed or arranged in the same plane to generate a moiré array. In embodiments where the first and second periodic arrays are placed or arranged in the same plane, the nanoparticles can be either metallic nanoparticles or dielectric nanoparticles. The first and second periodic arrays can also be arranged in separate layers, with the second periodic array in the second layer positioned above the first periodic array in the first layer, thereby generating a quasi-periodic array with a moiré effect. The nanoparticles in the first and second periodic array layers can be of the same type, such as both being metallic nanoparticles or both being dielectric nanoparticles, or they can be different types of nanoparticles, such as the first layer being dielectric nanoparticles and the second layer being metallic nanoparticles. If both layers include metallic nanoparticles, the outcoupling layer can include a dielectric spacer layer, with the first layer positioned above the dielectric spacer layer. The dielectric spacer layer can have a thickness of less than 20 nm, less than 30 nm, less than 50 nm, less than 100 nm, etc., and preferably 20 nm ± 5 nm. A dielectric material can be disposed between the nanoparticles in the first layer to form a planar surface above the nanoparticles. A second nanoparticle layer can be disposed above the planar surface.

[0028] In embodiments where the first layer includes dielectric nanoparticles, regardless of whether the second layer includes dielectric or metallic nanoparticles, the outcoupling layer may include a dielectric spacer layer with a thickness of less than 2 nm, or may not include a dielectric spacer layer at all. The first layer may be disposed above the dielectric spacer layer, or in embodiments without a dielectric spacer layer, it may be disposed on the reinforcement layer. The dielectric nanoparticles of the first periodic array may be disposed within a dielectric material, wherein the refractive index of the dielectric nanoparticles is at least 0.5 greater than the refractive index of the dielectric material. The second nanoparticle layer may be disposed above the first nanoparticle layer.

[0029] The device may be a consumer electronic device or a part of a consumer electronic device, which may be at least one type selected from the group consisting of: flat panel displays, curved displays, computer monitors, medical monitors, televisions, billboards, lights for internal or external lighting and / or signaling, head-up displays, fully transparent or partially transparent displays, flexible displays, rollable displays, foldable displays, stretchable displays, laser printers, telephones, cellular phones, tablet computers, phablets, personal digital assistants (PDAs), wearable devices, laptop computers, digital cameras, camcorders, viewfinders, microdisplays with a diagonal of less than 2 inches, 3D displays, virtual reality or augmented reality displays, vehicles, automotive displays, video walls comprising multiple displays tiled together, theater or stadium screens and signs. Attached Figure Description

[0030] Figure 1 An organic light-emitting device was displayed.

[0031] Figure 2 An inverted organic light-emitting device without an independent electron transport layer was demonstrated.

[0032] Figure 3 (a) and (b) show schematic diagrams of plasmonic OLEDs. Figure 3 (a) shows a plasmonic OLED, in which the enhancement layer is the second electrode. Figure 3 (b) shows a plasmonic OLED with a separate enhancement layer and a second electrode.

[0033] Figure 4 a) and b) illustrate simulated modes of a plasmonic OLED device using a square array of silver nanoparticles for optical decoupling. The numbers in parentheses represent the Miller indices for different lattice modes. Figure 4 a) shows the simulated surface lattice resonance (SLR) mode. Figure 4 b) shows a simulated plasmon-mediated surface lattice resonance (PSLR) mode.

[0034] Figure 5 a) to f) show the positions of nanoparticles and the corresponding geometric structure factor points for different array types. Figure 5 a) shows the positions of the nanoparticles in the square array. Figure 5 b) shows Figure 5 a) The corresponding geometric structure factor points of the square array. Figure 5 c) shows the positions of the nanoparticles in the hexagonal array. Figure 5 d) shows Figure 5 c) The corresponding geometric structure factor points of the hexagonal array. Figure 5 e) shows that by Figure 5 a) square lattice array and Figure 5 The positions of nanoparticles in a quasi-periodic array formed by combining hexagonal lattice arrays of c) Figure 5 f) shows Figure 5 The corresponding geometrical structure factor points of the quasi-periodic array of e).

[0035] Figure 6 a) through c) show the nanoparticle positions, corresponding geometry factor points, and simulated emission profiles of a plasmonic OLED using a Penrose-based quasi-periodic array in the decoupling layer. Figure 6 a) shows the nanoparticle positions based on a Penrose-based quasi-periodic array. Figure 6 b) shows Figure 6 The corresponding geometrical structure factor points of the quasi-periodic array of a). Figure 6 c) shows Figure 6 Simulated emission profile of the quasi-periodic array of (a).

[0036] Figure 7 a) shows simulated EQE plots based on a Penrose-based quasi-periodic array (black) and a square array (grey), which demonstrate the enhanced optical outcoupling of the quasi-periodic array. Figure 7 b) shows a simulated lattice dispersion of a Penrose-based quasi-periodic array using the finite-difference time-domain (FDTD) method.

[0037] Figure 8 (a) through (f) show exemplary quasi-periodic high-symmetry arrays from tessellation patterns and corresponding structure factor patterns for the arrays. Figure 8 (a) shows a quasi-periodic high-symmetric array from a tessellation pattern, where n=7. Figure 8 (d) shows Figure 8 The corresponding structure factor pattern of the array of (a). Figure 8 (b) shows a quasi-periodic high-symmetric array from a tessellation pattern, where n=9. Figure 8 (e) shows Figure 8 The corresponding structure factor pattern of array (b). Figure 8 (c) shows a quasi-periodic high-symmetric array from a tessellation pattern, where n=13. Figure 8 (f) shows Figure 8 The corresponding structure factor pattern of the array of (c).

[0038] Figure 9 a) through c) show the position and arrangement of nanoparticles in a moiré pattern formed by superimposing two square arrays, with one array rotated relative to the other. Figure 9 a) shows a moiré pattern formed by superimposing two square arrays, one of which is rotated 5° relative to the other. Figure 9 b) shows a moiré pattern formed by superimposing two square arrays, one of which is rotated 30° relative to the other. Figure 9 c) shows a moiré pattern formed by superimposing two square arrays, where one array is rotated 45° relative to the other.

[0039] Figure 10 (a) through (e) show schematic diagrams of plasmonic OLEDs utilizing arrays exhibiting the Mohr effect. Figure 10(a) shows a plasmonic OLED exhibiting the moiré effect, which is formed by a periodic array of recesses on a second electrode and a periodic array of metal nanoparticles. Figure 10 (b) shows a plasmonic OLED exhibiting a moiré effect formed by a periodic array of dielectric nanoparticles on a second electrode and an array of metal nanoparticles deposited on top of the dielectric nanoparticle array. Figure 10 (c) shows a plasmonic OLED exhibiting the moiré effect, which is formed by stacked layers of periodic arrays of metal nanoparticles. Figure 10 (d) shows a plasmonic OLED exhibiting a moiré effect formed by a periodic array of dielectric nanoparticles disposed in another dielectric material deposited on an enhancement layer and a second layer of periodic array of dielectric nanoparticles above the first layer. Figure 10 (e) shows a plasmonic OLED exhibiting a moiré effect formed by a periodic array of metal nanoparticles in a dielectric layer deposited on an enhancement layer and a periodic array of dielectric nanoparticles above a first layer.

[0040] Figure 11 Figures a through c show the position and arrangement of the nanoparticles. Figure 11 'a' shows a hexagonal array. Figure 11 b shows a chirped array with lattice periodicity variations. Figure 11 c represents a chirped array with array symmetry that varies from hexagonal to rectangular.

[0041] Figure 12 (a) and (b) show the position and arrangement of the three-dimensional nanoparticles. Figure 12 (a) shows three-dimensional metallic nanoparticles. Figure 12 (b) shows three-dimensional dielectric nanoparticles. Detailed Implementation

[0042] Generally, an OLED comprises at least one organic layer disposed between and electrically connected to both the anode and cathode. When a current is applied, holes are injected into the anode and electrons into the organic layer from the cathode. The injected holes and electrons migrate toward their respective oppositely charged electrodes. When electrons and holes are localized on the same molecule, an "exciton" is formed, which is a localized electron-hole pair with an excited energy state. When the exciton relaxes through a photoemission mechanism, light is emitted. In some cases, excitons may be localized on excimers or excited-state complexes. Non-radiative mechanisms (such as thermal relaxation) may also occur, but are generally considered undesirable.

[0043] Early OLEDs used emitting molecules that emitted light from a single state (“fluorescence”), as disclosed, for example, in U.S. Patent No. 4,769,292, which is incorporated herein by reference in its entirety. Fluorescence emission typically occurs within timeframes of less than 10 nanoseconds.

[0044] Recently, OLEDs with emitting materials that emit light from the triplet state (“phosphorescence”) have been demonstrated. Baldo et al., “Highly Efficient Phosphorescent Emission from Organic Electroluminescent Devices,” Nature, Vol. 395, 151-154, 1998 (“Baldo-I”); and Baldo et al., “Very high-efficiency green organic light-emitting devices based on electrophosphorescence,” Applied Physics Letters, Vol. 75, 3, 4-6 (1999) (“Baldo-II”), are incorporated herein by reference in their entirety. Phosphorescence is described in more detail in columns 5-6 of U.S. Patent No. 7,279,704, which is incorporated herein by reference.

[0045] Figure 1 An organic light-emitting device 100 is shown. The figures are not necessarily drawn to scale. Device 100 may include a substrate 110, an anode 115, a hole injection layer 120, a hole transport layer 125, an electron blocking layer 130, an emission layer 135, a hole blocking layer 140, an electron transport layer 145, an electron injection layer 150, a protective layer 155, a cathode 160, and a blocking layer 170. The cathode 160 is a composite cathode having a first conductive layer 162 and a second conductive layer 164. Device 100 can be fabricated by sequentially depositing the layers. The properties and functions of these various layers, as well as example materials, are described in more detail in columns 6-10 of US 7,279,704, which is incorporated herein by reference.

[0046] Further examples of each of these layers are available. For instance, a flexible and transparent substrate-anode combination is disclosed in U.S. Patent No. 5,844,363, which is incorporated herein by reference in its entirety. An example of a p-doped hole transport layer is m-MTDATA doped with F4-TCNQ in a 50:1 molar ratio, as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, which is incorporated herein by reference in its entirety. Examples of emitting and host materials are disclosed in U.S. Patent No. 6,303,238 to Thompson et al., which is incorporated herein by reference in its entirety. An example of an n-doped electron transport layer is BPhen doped with Li in a 1:1 molar ratio, as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, which is incorporated herein by reference in its entirety. Examples of cathodes, comprising composite cathodes having a thin layer of metal (e.g., Mg:Ag) having an overlying transparent, conductive, sputtered ITO layer, are disclosed in their entirety in U.S. Patent Nos. 5,703,436 and 5,707,745, which are incorporated herein by reference in their entirety. Theories and uses of barrier layers are described in more detail in U.S. Patent No. 6,097,147 and U.S. Patent Application Publication No. 2003 / 0230980, which are incorporated herein by reference in their entirety. Examples of implantation layers are provided in U.S. Patent Application Publication No. 2004 / 0174116, which is incorporated herein by reference in its entirety. A description of protective layers can be found in U.S. Patent Application Publication No. 2004 / 0174116, which is incorporated herein by reference in its entirety. Barrier layer 170 may be a single layer or multiple layers and may cover or surround other layers of the device. Barrier layer 170 may also surround substrate 110, and / or it may be disposed between the substrate and other layers of the device. A barrier layer, also known as an encapsulation, encapsulation layer, protective layer, or permeation barrier, typically provides protection against moisture, ambient air, and other similar materials permeating through other layers of a device. Examples of barrier layer materials and structures are provided in U.S. Patent Nos. 6,537,688, 6,597,111, 6,664,137, 6,835,950, 6,888,305, 6,888,307, 6,897,474, 7,187,119, and 7,683,534, each of which is incorporated herein by reference in its entirety.

[0047] Figure 2An inverted OLED 200 is shown. The device includes a substrate 210, a cathode 215, an emitter layer 220, a hole transport layer 225, and an anode 230. The device 200 can be fabricated by sequentially depositing these layers. Because the most common OLED configuration has a cathode disposed above the anode, and the device 200 has a cathode 215 disposed below the anode 230, the device 200 can be referred to as an "inverted" OLED. Materials similar to those described with respect to device 100 can be used in the corresponding layers of the device 200. Figure 2 Provide an example of how some layers can be omitted from the structure of device 100.

[0048] Figure 1 and 2 The simple layered structures illustrated herein are provided by way of non-limiting examples, and it should be understood that embodiments of the invention can be used in conjunction with various other structures. The specific materials and structures described are exemplary in nature, and other materials and structures can be used. Functional OLEDs can be obtained by combining the various layers described in different ways, or the layers can be omitted entirely based on design, performance, and cost factors. Other layers not specifically described may also be included. Materials other than those specifically described may be used. Although many examples provided herein describe various layers as comprising a single material, it should be understood that combinations of materials (such as mixtures of host and dopant) or more generally mixtures may be used. Furthermore, the layers may have various sublayers. The names given to the various layers herein are not intended to be strictly limiting. For example, in device 200, hole transport layer 225 transports holes and injects holes into emitter layer 220, and may be described as a hole transport layer or a hole injection layer. In one embodiment, an OLED may be described as having an “organic layer” disposed between a cathode and an anode. This organic layer may comprise a single layer, or may further comprise, for example, regarding Figure 1 and 2 Multiple layers of the different organic materials mentioned above.

[0049] Structures and materials not specifically described can also be used, such as OLEDs (PLEDs) containing polymeric materials, as disclosed in, for example, U.S. Patent No. 5,247,190 to Friend et al., which is incorporated herein by reference in its entirety. By another example, OLEDs with a single organic layer can be used. OLEDs can be stacked, for example as described in, for example, U.S. Patent No. 5,707,745 to Forrest et al., which is incorporated herein by reference in its entirety. OLED structures can deviate from... Figure 1 and 2The simple layered structure described herein. For example, the substrate may include angled reflective surfaces to improve out-coupling, such as the tabletop structure described in U.S. Patent No. 6,091,195 to Forrest et al., and / or the recessed structure described in U.S. Patent No. 5,834,893 to Bulovic et al., which are incorporated herein by reference in their entirety.

[0050] In some embodiments disclosed herein, the emission layer or material (e.g. Figure 1-2 The emitting layers 135 and 220 shown herein may include quantum dots. The emitting layers may use various emitting display technologies. These technologies may include inorganic and / or organic devices such as LEDs, mini-LEDs, micro-LEDs, thin electroluminescent films, organic light-emitting devices, etc. Unless explicitly indicated to the contrary or as understood by one of ordinary skill in the art, the term "emitting layer" or "emitting material" as disclosed herein may include organic emitting materials and / or emitting materials containing quantum dots or equivalent structures. Generally, an emitting layer includes emitting material within a host matrix. Such emitting layers may consist only of quantum dot material that converts light emitted by a separate emitting material or other emitting body, or may also include a separate emitting material or other emitting body, or may directly emit light by the application of an electric current. Similarly, color-changing layers, color filters, upconversion or downconversion layers, or structures may include materials containing quantum dots, but such layers are not necessarily considered "emitting layers" as disclosed herein. Typically, an "emitting layer" or material is a material that emits initial light based on injected charges. This initial light can be altered by another layer (e.g., a color filter or other color-changing layer) that does not itself emit the initial light within the device, but can re-emit altered light with different spectral content based on the absorption and down-conversion of the initial light emitted by the emitting layer to lower energy light emission. In some embodiments disclosed herein, the color-changing layer, color filter, up-conversion, and / or down-conversion layer can be disposed externally to the OLED device, for example, above or below the electrodes of the OLED device.

[0051] Unless otherwise specified, any of the layers in the various embodiments may be placed, positioned, or deposited by any suitable method. For organic layers, preferred methods include thermal evaporation, inkjet printing (as described in U.S. Patent Nos. 6,013,982 and 6,087,196, which are incorporated herein by reference in their entirety), organic vapor deposition (OVPD) (as described in U.S. Patent No. 6,337,102 by Foster et al., which are incorporated herein by reference in their entirety), and deposition via organic vapor jet printing (OVJP) (as described in U.S. Patent No. 7,431,968, which is incorporated herein by reference in its entirety). Other suitable deposition methods include spin coating and other solution-based processes. Solution-based processes are preferably performed in a nitrogen or inert atmosphere. For other layers, preferred methods include thermal evaporation. Preferred patterning methods include deposition via a mask, cold soldering (as described in U.S. Patents 6,294,398 and 6,468,819, which are incorporated herein by reference in their entirety), and patterning associated with some of the deposition methods such as inkjet and OVJD. Other methods may also be used. The material to be deposited may be modified to suit a particular deposition method. For example, branched or unbranched substituents, preferably containing at least three carbons, such as alkyl and aryl groups, may be used in small molecules to enhance their solution handling ability. Substituents having 20 or more carbons may be used, with 3 to 20 carbons being a preferred range. Materials with asymmetric structures may have better solution handleability than those with symmetric structures because asymmetric materials may have a lower tendency to recrystallize. Dendritic polymer substituents may be used to enhance the solution handling ability of small molecules.

[0052] Devices manufactured according to embodiments of the present invention may optionally further include a barrier layer. One use of the barrier layer is to protect the electrodes and organic layers from damage caused by exposure to harmful substances in an environment including moisture, vapor, and / or gases. The barrier layer may be deposited on, under, or beside a substrate or electrode, or on any other part of the device, including edges. The barrier layer may comprise a single layer or multiple layers. The barrier layer can be formed using various known chemical vapor deposition techniques and may comprise compositions having a single phase and compositions having multiple phases. Any suitable material or combination of materials may be used for the barrier layer. The barrier layer may contain inorganic or organic compounds, or both. Preferred barrier layers comprise a mixture of polymeric and non-polymeric materials, as described in U.S. Patent No. 7,968,146, PCT Patent Application Nos. PCT / US2007 / 023098 and PCT / US2009 / 042829, which are incorporated herein by reference in their entirety. For the process to be considered a "mixture," the aforementioned polymeric and non-polymeric materials constituting the barrier layer should be deposited and / or deposited simultaneously under the same reaction conditions. The weight ratio of polymeric to non-polymeric materials can range from 95:5 to 5:95. The polymeric and non-polymeric materials can be produced from the same precursor material. In one example, the mixture of polymeric and non-polymeric materials is essentially composed of polymeric silicon and inorganic silicon.

[0053] In some embodiments, at least one of the anode, cathode, or a new layer disposed above the organic emitter layer serves as a reinforcement layer. The reinforcement layer comprises a plasmonic material exhibiting surface plasmon resonance, which is nonradiatively coupled to the emitter material and transfers excited-state energy from the emitter material to the nonradiative mode of the surface plasmon polariton. The reinforcement layer is provided at a threshold distance not exceeding that of the organic emitter layer, wherein the emitter material has a total nonradiative decay rate constant and a total radiative decay rate constant due to the presence of the reinforcement layer, and the threshold distance is a distance where the total nonradiative decay rate constant is equal to the total radiative decay rate constant. In some embodiments, the OLED further comprises an decoupling layer. In some embodiments, the decoupling layer is disposed above the reinforcement layer on the opposite side of the organic emitter layer. In some embodiments, the decoupling layer is disposed on the opposite side of the emitter layer to the reinforcement layer, but still decouples energy from the surface plasmon modes of the reinforcement layer. The decoupling layer scatters or extracts energy from the surface plasmon polariton. In some embodiments, this energy is scattered or extracted into free space in the form of photons. In other embodiments, energy is scattered or extracted from the surface plasmon modes of the device into other modes, such as, but not limited to, organic waveguide modes, substrate modes, or another waveguide mode. If energy is scattered or extracted into the non-free-space modes of the OLED, other decoupling schemes can be incorporated to extract energy into free space. In some embodiments, one or more dielectric spacer layers may be disposed between the reinforcement layer and the decoupling layer. The plasmon stack may include a dielectric spacer material (i.e., a dielectric spacer layer) whose refractive index is selected based on the color of light emitted by the organic emitting material. In one embodiment, the dielectric spacer material (i.e., the dielectric spacer layer) may be positioned between the reinforcement layer and the nanoparticles in the plasmon stack. In an alternative embodiment, the dielectric spacer material may be positioned between two electrodes in the plasmon stack. In yet another embodiment, the dielectric spacer material may be located on either side of either electrode outside the plasmon stack, but not necessarily adjacent to either electrode. In yet another embodiment, the dielectric spacer material may be located between the reinforcement layer and the decoupling layer or may be integrated within the decoupling layer. In some embodiments, the dielectric spacer layer may exist only in plasmonic stacked subpixels, only in non-platinonic stacked subpixels, or in both. Examples of materials suitable for the dielectric spacer layer include dielectric materials, including organic, inorganic, perovskite, and oxide materials, and may include stacks and / or mixtures of these materials.

[0054] The enhancement layer modifies the effective properties of the medium in which the emitter material resides, thereby causing any or all of the following: reduced emissivity, modification of emission spectral shape, changes in emission intensity and angle, changes in the stability of the emitter material, changes in OLED efficiency, and reduced efficiency degradation of the OLED device. Placing the enhancement layer on the cathode side, anode side, or both sides produces an OLED device that utilizes any of the above effects. In addition to the specific functional layers mentioned herein and illustrated in the various OLED examples shown in the figures, the OLED according to the invention may also include any of the other functional layers commonly found in OLEDs.

[0055] The reinforcing layer can be composed of plasmonic materials, optically active metamaterials, or hyperbolic metamaterials. As used herein, plasmonic materials are materials whose real portion of the dielectric constant crosses zero in the visible or ultraviolet region of the electromagnetic spectrum. In some embodiments, the plasmonic material comprises at least one metal. In such embodiments, the metal may include at least one of the following: Ag, Al, Au, Ir, Pt, Ni, Cu, W, Ta, Fe, Cr, Mg, Ga, Rh, Ti, Ru, Pd, In, Bi, Ca, alloys or mixtures of these materials, and stacks of these materials. Generally, metamaterials are media composed of different materials, wherein the medium as a whole acts differently than the sum of its material parts. Specifically, we define optically active metamaterials as materials having both a negative dielectric constant and negative permeability. On the other hand, hyperbolic metamaterials are anisotropic media, wherein the permittivity or permeability has different signs for different spatial orientations. Optically active metamaterials and hyperbolic metamaterials are strictly distinguished from many other photonic structures, such as distributed Bragg reflectors (DBRs), because the medium must be uniform along the length scale of the light wavelength in the direction of propagation. Using terminology understood by those skilled in the art, the dielectric constant of the metamaterial in the direction of propagation can be approximated by an effective medium. Plasmon materials and metamaterials offer methods for controlling light propagation that can enhance OLED performance in a variety of ways.

[0056] In some embodiments, the enhancement layer is provided as a planar layer. In other embodiments, the enhancement layer has wavelength-sized features arranged periodically, quasi-periodicly, or randomly, or subwavelength-sized features arranged periodically, quasi-periodicly, or randomly. In some embodiments, the wavelength-sized features and subwavelength-sized features have sharp edges.

[0057] In some embodiments, the decoupling layer is characterized by a wavelength size arranged periodically, quasi-periodicly, or randomly, or by a subwavelength size arranged periodically, quasi-periodicly, or randomly. In some embodiments, the decoupling layer may be composed of a plurality of nanoparticles, and in other embodiments, the decoupling layer is composed of a plurality of nanoparticles disposed on a material. In these embodiments, decoupling can be tuned by at least one of the following: changing the size of the plurality of nanoparticles, changing the shape of the plurality of nanoparticles, changing the material of the plurality of nanoparticles, adjusting the thickness of the material, changing the refractive index of the material or an additional layer disposed on the plurality of nanoparticles, changing the thickness of the reinforcing layer, and / or changing the material of the reinforcing layer. The plurality of nanoparticles of the device may be formed from at least one of the following: metal, dielectric material, semiconductor material, metal alloy, mixture of dielectric materials, stack or layering of one or more materials, and / or a core of one type of material, wherein the core is coated with a shell of a different type of material. In some embodiments, the decoupling layer is composed of at least metal nanoparticles, wherein the metal is selected from the group consisting of: Ag, Al, Au, Ir, Pt, Ni, Cu, W, Ta, Fe, Cr, Mg, Ga, Rh, Ti, Ru, Pd, In, Bi, Ca, alloys or mixtures of these materials, and stacks of these materials. Multiple nanoparticles may have additional layers disposed on them. In some embodiments, the polarization of the emission can be tuned using the decoupling layer. Changing the dimension and periodicity of the decoupling layer can select a type of polarization that preferentially decouples to air. In some embodiments, the decoupling layer also functions as an electrode of the device.

[0058] In embodiments of the disclosed subject matter, the apparatus may include an enhancement layer disposed above an emission region of at least one sub-pixel configured to have Lambertian emission and / or at least one sub-pixel configured to have a microcavity for direct emission, as described in detail below. In at least some of these embodiments, the enhancement layer may include a plasmonic structure disposed at a predetermined threshold distance from the emission region. The predetermined threshold distance may be a distance where the total nonradiative decay rate constant is equal to the total radiative decay rate constant. In some of these embodiments, the apparatus may include an excoupling layer disposed above the enhancement layer on the opposite side of the emission region.

[0059] It is believed that the internal quantum efficiency (IQE) of fluorescent OLEDs can exceed the 25% spin statistical limit through delayed fluorescence. As used in this paper, there are two types of delayed fluorescence: P-type delayed fluorescence and E-type delayed fluorescence. P-type delayed fluorescence is generated by triplet-triplet annihilation (TTA).

[0060] In some embodiments, the emitting material and / or compounds in the layers of the OLED can be used as phosphorescent photosensitizers, wherein one or more layers in the OLED can include acceptors in the form of one or more fluorescent and / or delayed fluorescent emitters. In some embodiments, the compound can be used as a component of an excitation complex, which functions as a sensitizer. As a phosphorescent photosensitizer, the compound can be able to transfer energy to the acceptor, and the acceptor can emit energy or further transfer energy to a final emitter. The acceptor concentration can range from 0.001% to 100%. The acceptor can be in the same layer as the phosphorescent photosensitizer or in one or more different layers. In some embodiments, the acceptor can be a TADF emitter. In some embodiments, the acceptor can be a fluorescent emitter. In some embodiments, emission can be generated by any one or all of the sensitizer, the acceptor, and / or the final emitter.

[0061] On the other hand, the aforementioned E-type delayed fluorescence does not depend on the collision of two triplet states, but rather on the thermal population between the triplet and singlet excited states. Compounds capable of producing E-type delayed fluorescence are required to have a very small singlet-triple gap. Thermal energy can activate transitions from the triplet state back to the singlet state. This type of delayed fluorescence is also called thermally activated delayed fluorescence (TADF). A significant characteristic of TADF is that the delayed component increases with increasing temperature due to increased thermal energy. If the reverse intersystem crossing rate is fast enough to minimize nonradiative decay from the triplet state, the fraction of singlet excited states that are refilled can reach 75%. The total singlet fraction can be 100%, far exceeding the spin statistical limit of electrically generated excitons.

[0062] E-type delayed fluorescence can be observed in excited complex systems or single compounds. Unbound by theory, it is believed that E-type delayed fluorescence requires the luminescent material to have a small singlet-triplet band gap (ΔES-T). Organic, metal-free donor-acceptor luminescent materials may be able to achieve this. The emission of these materials is typically characterized by donor-acceptor charge transfer (CT) emission. Spatial separation of the HOMO and LUMO in these donor-acceptor compounds usually results in a small ΔES-T. These states may involve CT states. Typically, donor-acceptor luminescent materials are constructed by linking an electron donor moiety (e.g., an amino or carbazole derivative) with an electron acceptor moiety (e.g., an N-containing six-membered aromatic ring).

[0063] Devices manufactured according to embodiments of the present invention can be incorporated into a wide variety of electronic component modules (or units), which can be incorporated into a variety of electronic products or intermediate components. Examples of such electronic products or intermediate components include displays, lighting devices (such as discrete light source devices or lighting panels), etc., which can be utilized by end-user product manufacturers. The electronic component module may optionally include driving electronics and / or a power supply. Devices manufactured according to embodiments of the present invention can be incorporated into a wide variety of consumer products having one or more electronic component modules (or units) incorporated therein. A consumer product incorporating an OLED is disclosed, wherein the OLED comprises compounds of the present disclosure in its organic layer. The consumer product should include any type of product containing one or more light sources and / or one or more of some type of visual display. Examples of the consumer products described include flat panel displays, curved displays, computer monitors, medical monitors, televisions, billboards, lights for internal or external lighting and / or signaling, head-up displays, fully transparent or partially transparent displays, flexible displays, rollable displays, foldable displays, stretchable displays, laser printers, telephones, cellular phones, tablet computers, phablets, personal digital assistants (PDAs), wearable devices, laptop computers, digital cameras, camcorders, viewfinders, microdisplays with a diagonal of less than 2 inches, 3D displays, virtual reality or augmented reality displays, vehicles, automotive displays, video walls comprising multiple tiled displays, theater or stadium screens, optical communication devices, and signage. Various control mechanisms, including passive and active matrices, can be used to control the devices manufactured according to the invention. Many of the devices are intended for use in temperature ranges comfortable for humans, such as 18°C ​​to 30°C, and more preferably at room temperature (20-25°C), but can be used outside this temperature range (e.g., -40°C to 80°C).

[0064] The materials and structures described herein can be applied to devices other than OLEDs. For example, other optoelectronic devices such as organic solar cells and organic photodetectors can utilize the materials and structures described herein. More generally, organic devices such as organic transistors can utilize the materials and structures described herein.

[0065] In some embodiments, the OLED has one or more features selected from the group consisting of: flexible, rollable, foldable, stretchable, and bendable. In some embodiments, the OLED is transparent or translucent. In some embodiments, the OLED further comprises a layer having carbon nanotubes.

[0066] In some embodiments, the OLED further comprises a layer having a delayed phosphor emitter. In some embodiments, the OLED comprises an RGB pixel arrangement or a white pixel arrangement with a color filter. In some embodiments, the OLED is a mobile device, a handheld device, or a wearable device. In some embodiments, the OLED is a display panel with a diagonal of less than 10 inches or an area of ​​less than 50 square inches. In some embodiments, the OLED is a display panel with a diagonal of at least 10 inches or an area of ​​at least 50 square inches. In some embodiments, the OLED is a lighting panel.

[0067] In some embodiments of the launch area, the launch area further includes a body.

[0068] In some embodiments, the light-generating compound may be an emission dopant. In some embodiments, the compound may generate emission via phosphorescence, fluorescence, thermally activated delayed fluorescence (TADF, also known as E-type delayed fluorescence), triplet-triplet annihilation, or a combination of these processes, including phosphorescently sensitized fluorescence.

[0069] The OLEDs disclosed herein can be incorporated into one or more consumer products, electronic component modules, and lighting panels. The organic layer can be an emission layer, and the compound can be an emission dopant in some embodiments, while in other embodiments it can be a non-emission dopant.

[0070] The organic layer may also include a host. In some embodiments, two or more hosts are preferred. In some embodiments, the host used may be a) bipolar, b) electron transport, c) hole transport, or d) wide-bandgap material that plays a minor role in charge transport. In some embodiments, the host may include a metal complex. The host may be an inorganic compound.

[0071] Combination with other materials

[0072] The materials described herein for use in specific layers of organic light-emitting devices can be used in combination with a wide variety of other materials present in the device. For example, the emission dopants disclosed herein can be used in combination with a wide variety of possible host layers, transport layers, blocking layers, injection layers, electrodes, and other layers. The materials described or mentioned below are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and those skilled in the art can readily consult the literature to identify other materials that can be used in combination.

[0073] The various emitting and non-emitting layers and arrangements disclosed herein can be made of different materials. Examples of suitable materials are disclosed in U.S. Patent Application Publication No. 2017 / 0229663, which is incorporated herein by reference in its entirety.

[0074] Conductive dopants:

[0075] Charge transport layers can be doped with conductive dopants to substantially alter their charge carrier density, which in turn changes their conductivity. Conductivity is increased by creating charge carriers in the matrix material and, depending on the type of dopant, can also achieve changes in the Fermi level of the semiconductor. Hole transport layers can be doped with p-type conductive dopants, while n-type conductive dopants are used in electron transport layers.

[0076] HIL / HTL:

[0077] The hole injection / transport materials used in this invention are not particularly limited, and any compound can be used, as long as the compound is commonly used as a hole injection / transport material.

[0078] EBL:

[0079] An electron blocking layer (EBL) can be used to reduce the number of electrons and / or excitons leaving the emitter layer. The presence of such a blocking layer in a device can result in generally higher efficiency and / or longer lifetime compared to similar devices lacking a blocking layer. Furthermore, the blocking layer can be used to confine emission to a desired area of ​​the OLED. In some embodiments, the EBL material has a higher LUMO (closer to vacuum level) and / or higher triplet energy compared to the emitter closest to the EBL interface. In some embodiments, the EBL material has a higher LUMO and / or higher triplet energy compared to one or more of the bodies closest to the EBL interface. In one aspect, the compound used in the EBL contains the same molecules or the same functional groups as those used in one of the bodies described below.

[0080] main body:

[0081] The light-emitting layer of the organic EL device of the present invention preferably contains at least a metal complex as the light-emitting material, and may contain a host material using a metal complex as a dopant material. Examples of the host material are not particularly limited, and any metal complex or organic compound can be used, as long as the triplet energy of the host is greater than that of the dopant. Any host material can be used with any dopant, as long as the triplet criterion is satisfied.

[0082] HBL:

[0083] Hole blocking layers (HBLs) can be used to reduce the number of holes and / or excitons leaving the emitter layer. The presence of such blocking layers in a device can result in generally higher efficiency and / or longer lifetime compared to similar devices lacking a blocking layer. Furthermore, blocking layers can be used to confine emission to a desired area of ​​the OLED. In some embodiments, the HBL material has a lower HOMO (farthest from vacuum level) and / or higher triplet energy compared to the emitter closest to the HBL interface. In some embodiments, the HBL material has a lower HOMO and / or higher triplet energy compared to one or more of the bodies closest to the HBL interface.

[0084] ETL:

[0085] An electron transport layer (ETL) may comprise a material capable of transporting electrons. The ETL may be intrinsic (undoped) or doped. Doping can be used to enhance conductivity. Examples of ETL materials are not particularly limited, and any metal complex or organic compound may be used, provided it is typically used for electron transport.

[0086] Charge generation layer (CGL)

[0087] In tandem or stacked OLEDs, the conduction layer (CGL) plays a fundamental role in performance. It consists of an n-doped layer and a p-doped layer, respectively, for injecting electrons and holes. Electrons and holes are supplied by the CGL and the electrodes. Electrons and holes consumed in the CGL are refilled by electrons and holes injected from the cathode and anode, respectively; subsequently, the bipolar current gradually reaches a steady state. Typical CGL materials include n- and p-conductive dopants used in the transport layer.

[0088] In plasmonic OLEDs, nanoparticles in the decoupling layer control not only the optical decoupling efficiency but also the emission profile of the device. For a randomly ordered array of nanoparticles in the decoupling layer, the optical decoupling efficiency increases with the particle fill fraction until the average edge-to-edge spacing between two adjacent particles is comparable to the particle size. Further increasing the particle density will lead to a decrease in optical decoupling efficiency due to the increased optical loss associated with interparticle coupling between nearby particles. For devices using random particle arrays for optical decoupling, the emission profile is more like a Lambertian profile. Further enhancements to device efficiency and emission profile can be achieved by tuning the particle arrangement in the decoupling layer. The described devices include nanoparticle array designs that achieve enhanced device efficiency and a tunable emission profile by tuning the symmetry of the nanoparticle array in the decoupling layer.

[0089] The described device includes a substrate, a first electrode, an emitter layer disposed above the first electrode, a reinforcement layer disposed above the emitter layer, and a coupling layer disposed above the reinforcement layer. The device may include different variations of the layers, such as additional layers, layers of different orders, etc. Figure 1 and Figure 2 This describes such stacking. For example, plasmonic OLEDs can be "flipped," similar to... Figure 2 The arrangement of the nanoparticle layer, which is closer to the substrate, is described. The device includes a unique decoupling layer in which the nanoparticles form a quasi-periodic array. These arrays can provide a significant enhancement in optical decoupling efficiency and also provide tunability to the emission profile of the device. In some embodiments, these arrays can reduce angle-dependent emission color shift. Figure 3 A schematic diagram of a plasmonic OLED is shown, illustrating an organic layer 300, an emitter layer (EML) 310, a reinforcement layer 320, and an excoupling layer 350. In some embodiments, and as shown... Figure 3 As shown in (a), the metal cathode or second electrode is the enhancement layer 320 of the plasmonic OLED. In this embodiment, the thickness of the enhancement layer 320 can be less than 20 nm, less than 30 nm, less than 50 nm, less than 75 nm, etc., or preferably 40 nm ± 5 nm. The enhancement layer 320, which serves as the second electrode, can be made of a metallic material, such as gold, silver, aluminum, platinum, rhodium, etc.

[0090] In some embodiments and as Figure 3 As shown in (a), the second electrode 330 can be deposited above the emitter layer 310. When using an electrode layer 330 separate from the reinforcement layer 320, the electrode 330 can be deposited above the organic (emitter) layer 310 and the reinforcement layer 320 can be disposed above the second electrode 330. In some embodiments, the bottom surface of the reinforcement layer 320 can contact the top surface of the second electrode 330. Alternatively, the electrode 330 can be deposited above the reinforcement layer 320. In other words, the reinforcement layer 320 can be located between two electrodes, one of which is a thin layer of metallic or non-metallic material deposited above the reinforcement layer 320. Nanoparticles of the outcoupling layer 350 can then be deposited above the second electrode 330. A dielectric spacer layer 340 can be deposited between the second electrode 330 and the nanoparticle layer. The thickness of the dielectric spacer layer 340 can be less than 75 nm, less than 50 nm, and more preferably less than 20 nm. In some embodiments, the nanoparticles can be deposited directly above the second electrode 330.

[0091] Regardless of its location, the electrode can have a thickness of less than 60 nm. The electrode (which can be a first electrode, a second electrode, and / or other electrodes) can be made of optically transparent materials, such as indium tin oxide, fluorine-doped tin oxide, indium-doped zinc oxide, zinc aluminum oxide, indium-doped cadmium oxide, barium stannate, carbon nanotubes, graphene, multilayer graphene, single-layer graphene, graphene oxide, metal nanoparticles, nanowire-impregnated materials, polyacetylene, polypyrrole, polyindole, polyaniline, poly(p-phenylenevinylene), poly(3-alkylthiophene), (poly(3,4-ethylenedioxythiophene)), strontium niobium oxide, etc. The thickness of the second optically transparent electrode can be less than 60 nm, less than 50 nm, less than 30 nm, less than 20 nm, etc., or preferably 20 nm ± 5 nm. In some embodiments, the second electrode can be disposed above a reinforcement layer, wherein the reinforcement layer is disposed above the emitter layer. In such embodiments, the second electrode can be a metallic electrode or a non-metallic electrode (which may include an electrode having some metal and some non-metallic materials or an electrode having only non-metallic materials), with a thickness of less than 20 nm, less than 30 nm, less than 50 nm, less than 100 nm, etc., or preferably 30 nm ± 5 nm. The distance between the top of the emitting material layer and the bottom of the electrode can be less than 10 nm, less than 20 nm, less than 30 nm, less than 50 nm, less than 60 nm, less than 100 nm, etc., or preferably 20 nm ± 5 nm. The electrode can also be deposited directly on the top surface of the EML layer.

[0092] The decoupling layer comprises an array of nanoparticles deposited above or below the enhancement layer. The decoupling layer converts plasmons into light, preferably within the enhancement layer. The nanoparticles in the decoupling layer can be randomly ordered or periodically ordered with positional arrangement. The nanoparticles in the decoupling layer act as optical antennas to decouple the light. In addition to antenna-mode decoupling, plasmonic OLEDs with ordered arrays of nanoparticles also utilize collective modes within the decoupling layer to decouple light. For collective decoupling modes, the electromagnetic field induced by the plasmon modes in the enhancement layer is not confined to a single location but extends across several particles within the periodic array. This collective mode (also called a lattice mode) can enhance light emission at specific angles when the in-plane scattering components of the nanoparticle lattice undergo constructive interference. In some cases, collective mode light emission produces directional emission, while in others, when symmetry is high, the emission can be less directional. The emission pattern of a plasmonic OLED using an ordered nanoparticle array for optical decoupling is the convolution of the structure factor of the nanoparticle array and the momentum distribution of the emitter at the decoupling wavelength. The excitation energy from the emitter can be coupled to the array via the following path, given by the momentum matching conditions described below.

[0093] In the first example, the emission (i.e., photons) from the emitter is directly coupled to the nanoparticle lattice, which can couple without any plasmonic modes, thereby generating surface lattice resonance (SLR), which enhances optical decoupling at the emission wavelength given by the momentum-matching condition.

[0094] ,

[0095] in It is the wave vector of the incident light. It is the wave vector of the in-plane scattered component of light, where It is the angle between the incident light and the surface perpendicular to the device, and It was Miller Defined grating vector and representing the grating order.

[0096] In the second example, emission from the emitter is coupled into the surface plasmon mode of the enhancement layer. Photons are generated from the surface plasmon mode of the enhancement layer according to the following equation:

[0097] ,

[0098] in It is the wave vector associated with the surface plasmon mode. Due to the coupling with the surface plasmon mode, the plasmon-mediated surface lattice resonance (PSLR) will redshift from the SLR mode.

[0099] Figure 4 The calculated lattice modes of a plasmonic OLED device using a square array of silver nanoparticles for optical decoupling, based on the aforementioned momentum-matching conditions, are shown. The numbers in parentheses represent the Miller indices for different lattice modes. Figure 4 a) and b) show simulated dispersion modes for surface lattice resonance (SLR) and plasmonic-mediated surface lattice resonance (PSLR) modes, respectively. These modes are illustrated using an OLED device with a square array of silver nanocubes, where the lattice period is 300 nm for photocoupling. These dispersion curves indicate the light emission direction from the plasmonic OLED. The lattice dispersion of a plasmonic OLED using a nanoparticle array can be determined by measuring the angle-dependent emission spectrum or by using Fourier imaging. Additionally, Fourier plane imaging can provide a wave vector diagram for any emission wavelength, indicating the emission pattern of light emitted from the device. For the direction perpendicular to the device (… The light emission from the device, with its intersecting different lattice modes, enhances optical decoupling in these wavelength regions. Furthermore, the emission can be modified by changing the device's emission relative to the corresponding... The spectral position in the wavelength region is used to tune the light emission direction from the device. Optical decoupling of the device using an ordered nanoparticle array is achieved through antenna modes of individual nanoparticles and collective modes generated by lattice resonance modes due to the arrangement of multiple nanoparticles in the array. Optical decoupling caused by antenna modes results in a wider angular emission profile, while lattice dispersion modes induce directional emission in many cases. The angular emission profile depends on the relative intensity of each mode, which can be controlled by changing the spacer layer thickness. For smaller spacer layer thicknesses (<30 nm), the individual nanoantenna modes will be the dominant mode for optical decoupling, producing a wider emission profile, where the spectral position of the individual nanoparticles is tuned by the lattice resonance modes. The spectral overlap determines one or more emission angles with increased emission intensity. For larger spacer layer thicknesses, lattice modes will dominate optical decoupling, and the light emission can be highly directional. In one embodiment, for spacer layer thicknesses of 10–25 nm, single-particle decoupling modes dominate the emission profile. In other words, when the spacer layer thickness is 10–25 nm, more than 70% of the light is decoupled via single-particle decoupling. In one embodiment, for spacer layer thicknesses of 26–35 nm, a mixed mode of single-particle and lattice decoupling modes exists in the emission profile. In other words, when the spacer layer thickness is 26–35 nm, single-particle modes decouple 30–70% of the total decoupling light, while lattice decoupling modes account for 30–70% of the emitted light, where the total decoupling light via single-particle and lattice decoupling modes is 100%. In one embodiment, for spacer layer thicknesses greater than 36 nm, lattice decoupling modes dominate the emission profile. In other words, when the spacer layer thickness is greater than 36 nm, the light decoupled through the lattice decoupling mode accounts for more than 70% of the total decoupled light. For thicknesses less than 10 nm, the optical decoupling mechanism is more complex because the decoupling efficiency of individual particles becomes lower and may be equal to or lower than that of the lattice mode.

[0100] The emission profile of a device can be modified by altering the lattice dispersion mode. Specifically, the emission profile can be modified by arranging nanoparticles in the decoupling layer in a specific manner. This arrangement is characterized by array symmetry, which can be rotational symmetry, translational symmetry, etc. By optimizing the array symmetry, the decoupling efficiency of the device can be increased and the emission profile can be tuned. For example, Figure 5 a) and c) represent the positions of nanoparticles in square and hexagonal lattices, respectively. The symmetry of the array can be characterized by analyzing the Fourier transform of the particle positions within the array. Figure 5 The bright areas (also known as structure factor points) in the Fourier patterns shown in b) and d) represent the symmetry of the nanoparticle array. Figure 5 The Fourier patterns shown in b) and d) respectively correspond to Figure 5The arrays shown in a) and c) indicate square and hexagonal symmetrical patterns, respectively. The structure factor points indicate the emission pattern when light is emitted perpendicularly to the device. For non-perpendicular emission, the emission pattern can be determined by converting each structure factor point in the Fourier pattern into a circle, the radius of which is determined relative to the representation... The relative spectral positions within the wavelength region are defined. Square, hexagonal, and honeycomb lattices are considered highly ordered. A highly ordered array refers to an array of nanoparticles located at fixed distances from other nanoparticles, known as the lattice constant. In other words, at any position within the array, another nanoparticle will be located at a fixed distance from another nanoparticle in a specific direction.

[0101] Because the light energy of plasmonic OLEDs using ordered arrays of nanoparticles is decoupled through structure factor points, arrays with more structure factor points or higher symmetry can achieve enhanced light decoupling in plasmonic OLEDs. Arrays with increased symmetry and different short-range and long-range positional ordering can exhibit Fourier patterns. Symmetry can be rotational symmetry, translational symmetry, etc. These arrays can be classified as quasi-periodic arrays. A quasi-periodic array is an array design that lacks long-range positional ordering and whose short-range positional periodicity has a length scale no greater than the plasmonic propagation length of the enhancement layer. In other words, a quasi-periodic array is an array lacking long-range positional periodicity, and whose short-range positional ordering has a length scale comparable to or shorter than the plasmonic propagation length of the enhancement layer. The plasmonic propagation length of any plasmonic material is defined as the distance by which the energy within the surface plasmons decays to 1 / e times the maximum energy. The array is considered quasi-periodic because the distance between adjacent nanoparticles changes or varies at different array positions. In other words, at array locations separated by a length scale longer than the plasmon propagation length, the interparticle spacing between nearby nanoparticles is not uniform. The emission profile of the device can be tuned based on the choice of array symmetry in the nanoparticle array design within the decoupling layer. In other words, the choice of array with higher or lower rotational symmetry can be used to tune the emission profile of the device. It should be noted that the nanoparticle array comprises multiple nanoparticles arranged according to the design. To minimize the effects of near-field coupling between particles within the quasi-periodic array, the minimum interparticle spacing (i.e., the edge-to-edge spacing between two adjacent particles) can be kept larger than the maximum size of the nanoparticles. For example, the interparticle spacing can be at least 200 nm, at least 300 nm, at least 400 nm, at least 500 nm, etc.

[0102] One technique for generating or forming quasi-periodic arrays is by combining two or more basic or periodic lattice symmetries into an array. In other words, a quasi-periodic array is generated by embedding a first periodic array within a second periodic array. For ease of understanding, this document will discuss two periodic arrays; however, it should be noted that more than two periodic arrays can be combined to generate quasi-periodic arrays. For example, three, four, five, etc., periodic arrays can be combined to generate quasi-periodic arrays. In embodiments combining or embedding two periodic arrays, each periodic array can have different lattice symmetries and positional order. In other words, the first periodic array will have a first periodic order, and the second periodic array will have a second periodic order different from the first periodic order. In embodiments combining or embedding more than two periodic arrays, it may only be necessary to satisfy two differences in lattice symmetries or periodicity among the multiple periodic arrays. For example, in the case of three periodic arrays, the first and second periodic arrays can have lattice symmetries different from each other, but the third periodic array can have the same lattice symmetries as the first or second periodic arrays. Alternatively, all periodic arrays may have different lattice symmetries compared to each other. Different lattice symmetries may include square lattices, hexagonal lattices, tilted lattices, rectangular lattices, etc. In embodiments, periodic arrays with the same lattice symmetry may exist, but each lattice may have the same or different periodic spacing.

[0103] exist Figure 5 Example of generating a quasi-periodic array from two periodic arrays is shown in e). Figure 5 The corresponding structural factor pattern is displayed in f). Figure 5 The quasi-periodic array shown in e) is formed by Figure 5 A group of nanoparticles assembled into a square lattice periodic array of a) Figure 5 It is produced in a hexagonal lattice periodic array of c). In this example, Figure 5 c) The position of each nanoparticle in the hexagonal array is Figure 5 The four nanoparticles of the square array in (a) are replaced, thereby embedding the square array into the hexagonal array. In other words, Figure 5The quasi-periodic array of (e) is formed by hexagonally ordered particle unit cells or groups, where each unit cell or group has four particles arranged in a square lattice. Therefore, each nanoparticle position in the hexagonal array is replaced by a group of nanoparticles with a periodicity of square lattice. The number of nanoparticles in each group can be varied to produce more or less complex quasi-periodic arrays. For example, the number of groups of nanoparticles from the square array can be even, such as four, six, eight, etc. The lattice periodicity within each unit cell or group can be at least 100 nm, at least 200 nm, at least 300 nm, at least 400 nm, greater than 500 nm, etc. Figure 5 Compared to the basic periodic arrays of a) and c), Figure 5 The corresponding structure factor pattern shown in f) illustrates increased lattice symmetry.

[0104] It should be noted that reversing the embedding relationship between one periodic lattice symmetry and another will result in different quasi-periodic lattice designs. In other words, and for example in... Figure 5 In the example shown in e), Figure 5 a) A square lattice periodic array is embedded in Figure 5 c) In the hexagonal lattice periodic array. In other words, for each point in the hexagonal lattice periodic array, to locate the square lattice periodic array. However, if Figure 5 c) A hexagonal lattice periodic array is embedded in Figure 5 In the square lattice periodic array of a), in other words, locating the hexagonal lattice periodic array for each point in the square lattice periodic array will result in a quasi-periodic array design that is similar to... Figure 5 The quasi-periodic array design shown in e) differs from that in some embodiments. In some embodiments, quasi-periodic arrays can be fabricated by introducing chirp into the basic array. Chirp refers to a gradual and systematic change in the lattice properties across the nanoparticle array. Positional chirp involves a gradual change in the lattice periodicity or interparticle spacing along one or more ordered directions in the nanoparticle array. Chirp can also be applied to the array symmetry, where the lattice symmetry can gradually change from one symmetry to another, for example, from hexagonal array symmetry to rectangular array symmetry. In some embodiments, variations in lattice periods can be applied over 10, 20, 50, or more than 100 lattice periods, for example, from period 1 to period 2. Chirp in the array broadens the lattice dispersion modes, including… This region can broaden the optical decoupling generated by the lattice mode. Array chirping, by maximizing the spectral overlap with the lattice mode, can benefit devices using broadband emitters by improving optical decoupling efficiency.

[0105] In some embodiments, quasi-periodic arrays can be higher-order arrays than arrays created by embedding one periodic array within another. One technique for generating these higher-order arrays is cut-projection. Cut-projection is a mathematical technique in which a higher-dimensional lattice is projected onto a two-dimensional plane to create a tessellation pattern. Once the tessellation pattern is generated, nanoparticles can be positioned at points defined by the vertices of the tessellation pattern to generate a quasi-periodic array. For example, a five-dimensional cubic lattice can be formed by stacked cubes. The five-dimensional lattice is then projected onto a two-dimensional plane to create a Penrose tessellation pattern. By increasing the dimension of the lattice to be projected, the array symmetry of the projected array is increased. The increase in the symmetry points of the array (which are points in the Fourier pattern or inverse space, also known as structure factor points) improves the decoupling efficiency of the device. Due to the increased rotational and translational symmetry, quasi-periodic arrays can exhibit a variety of dispersion modes. In some embodiments, with gradually varying interparticle spacing, exemplary chirped quasi-periodic arrays can exhibit wider lattice dispersion modes, thereby broadening the optical decoupling generated by the lattice modes. This can result in a wider angular emission profile because the array modes are not in resonance with the emission peak, causing light to be emitted at an angle deviating from the vertical direction. In some embodiments, the angular emission profile generated by the quasi-periodic array may be wider than the Lambertian profile. In some other embodiments, when the quasi-periodic array has multiple discrete interparticle spacings, multiple sharp lattice dispersion modes can be observed. Each of these dispersion modes can induce light emission in a specific emission direction based on spectral overlap with the emission spectrum. The angular emission profiles of these devices can show multiple emission directions generated by the lattice modes and a boundary emission profile generated by the decoupling mode of a single nanoantenna. Figure 11 Figures a through c show the position and arrangement of the nanoparticles. Figure 11 'a' shows a hexagonal array. Figure 11 b shows a chirped array with lattice periodicity variations. Figure 11 c represents a chirped array that exhibits array symmetry, varying from hexagonal to rectangular. Figure 12 (a) and (b) show the position and arrangement of the 3D nanoparticles. Figure 12 (a) shows the 3D metal nanoparticle 1255. Figure 12 (b) illustrates 3D dielectric nanoparticles 1260. In some embodiments, the nanoparticles in the coupling layer 1250 can be formed into a 3D lattice exhibiting positional ordering and array symmetry in an out-of-plane (i.e., perpendicular to the reinforcing layer 1220) direction. In one embodiment, as... Figure 12As shown in (a) and (b), at least a portion of the nanoparticles may be surrounded by another layer (i.e., a spacer layer or dielectric layer 1240). In one embodiment, when dielectric nanoparticles are used, the other layer surrounding the nanoparticles may have a refractive index selected from the group consisting of: less than 2.5, less than 2.0, less than 1.9, less than 1.8, less than 1.7, less than 1.6, and less than 1.5. The symmetry of the nanoparticle array may include, but is not limited to, cube, rhombic, triangular, tetragonal, hexagonal, triclinic, monoclinic, body-centered cube, face-centered cube, etc.

[0106] An example of a high-order array is a quasi-periodic array with a Penrose design. Such a quasi-periodic array with a Penrose design... Figure 6 As shown in a), this quasi-periodic array is generated by a Penrose tessellation pattern formed by projecting a five-dimensional cubic lattice onto a two-dimensional plane. Figure 6 b) shows the representation by Figure 6 The Fourier pattern of geometrical structure factor points generated by the quasi-periodic array of a). Figure 6 b) shows an increase in the structure factor points of the array prepared by the Penrose tessellation pattern. This increase is due to the local and long-range positional ordering of the five-fold rotational symmetry of the Penrose tessellation pattern, and further illustrates the decrease in positional periodicity. Figure 6 c) describes the use of Figure 6 The simulated emission profile of the Penrose quasi-periodic array at 625 nm is shown in (a). The simulated emission profile is consistent with... Figure 6 The geometrical factor points shown in b) exhibit a high degree of consistency.

[0107] Figure 7 a) shows the estimated EQE variation curve of a plasmonic OLED using a Penrose-based quasi-periodic array for optical decoupling, which significantly improves the optical decoupling efficiency compared to a device using a square array of particles for optical decoupling. Figure 7 b) shows the EQE curve of a Penrose-based quasi-periodic array, which illustrates the effect of... Figure 7The broad peaks resulting from the modified lattice dispersion shown in b) are simulated using Ansys® Lumerical FDTDsolutions software with a finite-difference time-domain (FDTD) method. ANSYS is a registered trademark of Ansys Corporation in the U.S. and other countries. The different layers of the OLED device are presented with a computational volume of 7 µm × 7 µm × 1.5 µm by their refractive index values ​​and are closed in fully matched layers (PML) in all directions to match open boundary conditions. A single dipole emitter with a broad emission spectrum covering the entire visible light region (420–750 nm) in a vertical or horizontal orientation is placed 20 nm away from a 30 nm thick silver electrode to act as the emitter layer. The host medium is modeled using a 75 nm thick non-absorbing dielectric layer with a refractive index of 1.7. The metal and dielectric structures of the decoupling layer with optimal size and order are placed above the cathode. The refractive index values ​​determined experimentally are used to model the silver cathode, and the refractive index values ​​obtained by the Johnson and Christy experiments are used to model the metal structures (nanoparticles) in the decoupling layer. The computational volume was discretized using a rectangular grid with a non-uniform refractive index adjustment, at a resolution of 34 grid cells per wavelength. Furthermore, a grid over-control region with a 2 nm resolution was applied in the simulation region containing the silver cathode and metallic structure to minimize computational error. Purcell enhancement was evaluated by calculating the power emitter of the dipole using a monitor box surrounding the emitter and normalizing the emission power for free space. Far-field light emission was recorded using a frequency domain field and power monitor placed 500 nm above the decoupling layer to estimate the device's external quantum efficiency (EQE). The monitor also recorded the electric and magnetic field components induced by the dipole emitter.

[0108] As previously mentioned, higher-order arrays can be formed by increasing the dimensions of the higher-dimensional lattice to be projected. For example, using a cubic lattice, increasing the dimensions of the cubic lattice from five to six, seven, eight, etc., increases the order of the resulting quasi-periodic array. This increase in dimensions enhances the symmetry of the quasi-periodic array. Increasing the order of the resulting quasi-periodic array increases the number of structure factor points, thereby enhancing optical outcoupling. Figure 8 A quasi-periodic array is shown, resulting from the dimensional increase of a higher-dimensional cubic lattice. Figure 8 (a) shows a quasi-periodic high-symmetry array from a tessellation pattern, where the cubic lattice has a dimension of 7. Figure 8 (d) shows Figure 8 The corresponding structure factor pattern of the array of (a). Figure 8 (b) shows a quasi-periodic high-symmetry array from a tessellation pattern, wherein the cubic lattice has a dimension of 9. Figure 8 (e) shows the representation Figure 8 The corresponding Fourier pattern of the structure factor points of array (b). Figure 8 (c) shows a quasi-periodic high-symmetry array from a tessellation pattern, wherein the cubic lattice has a dimension of 13. Figure 8 (f) shows the representation Figure 8 The Fourier pattern corresponding to the structure factor points of array (c). It should be noted that as array symmetry increases, a wider range of interparticle spacing can affect decoupling efficiency, especially when the edge-to-edge spacing between adjacent nanoparticles is smaller than the nanoparticle size. This near-field coupling between nanoparticles can reduce decoupling efficiency. Therefore, to mitigate these effects, the nanoparticle ordering can be locally modified at array locations, where the edge-to-edge spacing between adjacent nanoparticles is comparable to or smaller than the nanoparticle size, while minimizing changes in lattice symmetry.

[0109] Modifying the geometrical factor points using a quasi-periodic array provides an efficient way to tune the emission pattern of a plasmonic OLED, which also enhances optical decoupling. The metal nanoparticles used in the decoupling layer can have shapes such as cubes, spheres, hemispheres, cylinders, rectangles, etc. In one embodiment, the metal nanoparticles can have a maximum cross-sectional size within a shape between 5 nm and 1000 nm. In one embodiment, if the metal nanoparticle 1060 is a cube or rectangular prism, then the maximum length of a single edge of the cube or rectangular prism is between 5 nm and 1000 nm. The minimum in-plane particle size of the metal nanoparticles can be greater than 10 nm, greater than 50 nm, greater than 100 nm, greater than 200 nm, greater than 300 nm, greater than 500 nm, greater than 1000 nm, greater than 1500 nm, greater than 2000 nm, etc. The out-of-plane dimensions of the metal nanoparticles can be greater than 10 nm, 50 nm, 100 nm, 200 nm, 300 nm, 500 nm, 1000 nm, 1500 nm, or 2000 nm. The coupling layer can also include a dielectric spacer layer with a thickness of less than 20 nm, 30 nm, 50 nm, or 100 nm, or preferably 20 nm ± 5 nm. The dielectric spacer layer can be disposed above the reinforcement layer, and the nanoparticle array can be disposed above the dielectric spacer layer. The refractive index of the dielectric spacer layer can be less than 1.5, less than 2, or less than 2.5.

[0110] In some embodiments, in addition to or instead of metal nanoparticles, the quasi-periodic array may include dielectric nanoparticles, meaning that the decoupling layer may include dielectric nanoparticles, metal nanoparticles, and / or a combination of both. The dielectric nanoparticles used in the decoupling layer may have shapes such as cylinders, cubes, hemispheres, cones, truncated cones, any random shape with a flat surface, etc. The refractive index of the dielectric material may be at least 1.5, at least 2, at least 2.5, at least 3, etc., or preferably 2.4 ± 0.2. In some embodiments, the quasi-periodic array is disposed directly on the reinforcement layer. In other embodiments, the decoupling layer may include a dielectric spacer layer with a thickness of less than 10 nm, which will be located between the reinforcement layer and the nanoparticle layer. In some embodiments, the dielectric spacer layer may not be included.

[0111] In some embodiments, the nanoparticles of the decoupling layer are arranged in a moiré pattern to control the emission pattern and emission direction of the plasmonic OLED. The moiré pattern can be formed by stacking multiple periodic arrays. For example, a quasi-periodic array exhibiting the moiré effect can be generated by stacking a first periodic array with a second periodic array. The periodic arrays are rotated relative to each other during the generation of the quasi-periodic array. In other words, a quasi-periodic array exhibiting the moiré effect can be formed by stacking multiple periodic nanoparticle arrays that are twisted relative to each other. Therefore, the symmetry of the periodic arrays can be the same or different. For example, the arrays used to generate the quasi-periodic array can be all square arrays, all hexagonal arrays, different array types, etc. The rotation angle between the arrays can be 1-15°, 16-30°, 31-45°, etc. Figure 9 This demonstrates a quasi-periodic array exhibiting the Mohr effect, formed using two equally periodic square arrays. Figure 9 In (a), a square array is rotated 5° relative to each other to form a quasi-periodic array. Figure 9 In b), the square array is rotated 30° relative to each other to form a quasi-periodic array. Figure 9 In (c), a square array is rotated 45° relative to each other to form a quasi-periodic array. The rotation angle can be selected to tune the radiation pattern and emission direction of the device. In other words, the low spatial frequency moiré pattern formed by the superposition of multiple high spatial frequency array patterns allows the radiation pattern and emission direction from the plasmonic OLED to be tuned by controlling the twist angle between the arrays. Furthermore, the moiré effect alters the lattice dispersion, producing a flatter dispersion, which reduces the angle-dependent color shift of the plasmonic OLED.

[0112] In some embodiments, nanoparticles of a first periodic array and nanoparticles of a second periodic array are arranged in the same plane to create a quasi-periodic moiré array. In this embodiment, the nanoparticles of the first periodic array and the nanoparticles of the second periodic array are of the same type. In other words, in this quasi-periodic array, the nanoparticles are either all metallic nanoparticles or all dielectric nanoparticles. In one embodiment, the nanoparticles of the moiré quasi-periodic array are fabricated in the dielectric spacer layer of the decoupling layer and disposed above the reinforcement layer. In some embodiments, the nanoparticles are fabricated directly above the reinforcement layer. In some embodiments, and as in... Figure 10 As shown in (a), the moiré pattern will be formed by an array of recesses in a reinforcement layer 1025, which is disposed above an emitter layer 1010, which is disposed above an organic layer 1000. The recesses will be filled with a dielectric material 1040, thereby planarizing the top surface. A nanoparticle layer 1050 will be disposed above this planarized top surface. The depth of the recesses can be at least 10 nm, at least 25 nm, less than 50 nm, etc. The refractive index of the dielectric material can be at least 1.5, at least 1.75, greater than 2, etc.

[0113] In some embodiments, periodic arrays are stacked to form a quasi-periodic array exhibiting the Mohr effect. In other words, a first periodic array will be the first layer, and a second periodic array will be the second layer. Since the periodic arrays will maintain a stacked structure, the nanoparticles in the quasi-periodic array can be different between the layers. For example, the first layer can be dielectric nanoparticles or metal nanoparticles. Then, the second layer can be dielectric nanoparticles or metal nanoparticles, regardless of the type of nanoparticles used in the first layer. Therefore, combinations of layers can be metal nanoparticle 1050 / metal nanoparticles, metal nanoparticles / dielectric nanoparticles 1060, dielectric nanoparticles / dielectric nanoparticles, and dielectric nanoparticles / metal nanoparticles (…). Figure 10 (as shown in (b)). In embodiments where the first (or bottom) layer is dielectric nanoparticles, the outcoupling layer may include a dielectric spacer layer with a thickness of less than 2 nm, wherein the dielectric nanoparticles are disposed above the dielectric spacer layer. In one embodiment, the dielectric nanoparticles may be disposed directly on the reinforcement layer.

[0114] In one embodiment, such as Figure 10As shown in (b), dielectric nanoparticles 1060 forming the first (or bottom) layer may be embedded within dielectric material 1055. The refractive index of the dielectric material may be less than 2, less than 1.8, less than 1.6, etc., or preferably less than 1.4. The refractive index of the dielectric particles may be at least 1.5, at least 2, at least 2.5, greater than 3, etc. The difference between the refractive index of the dielectric material and the refractive index of the dielectric particles may be at least 0.5. In other words, the refractive index of the dielectric particles is at least 0.5 greater than the refractive index of the dielectric material. In one embodiment, the dielectric nanoparticles 1060 may have a maximum cross-sectional dimension within a shape between 5 nm and 1000 nm. In one embodiment, if the dielectric nanoparticles 1060 are cubes or rectangular prisms, then the maximum length of a single edge of the cube or rectangular prism is between 5 nm and 1000 nm. In one embodiment, the dielectric nanoparticles may have a maximum in-plane size greater than 10 nm, greater than 50 nm, greater than 100 nm, greater than 200 nm, greater than 300 nm, greater than 500 nm, greater than 1000 nm, greater than 1500 nm, greater than 2000 nm, etc. In another embodiment, the maximum out-of-plane size of the dielectric nanoparticles may be greater than 10 nm, greater than 50 nm, greater than 100 nm, greater than 200 nm, greater than 300 nm, greater than 500 nm, greater than 1000 nm, greater than 1500 nm, greater than 2000 nm, etc. The thickness of the dielectric layer including the dielectric nanoparticles may be at least equal to, or greater than, the out-of-plane size of the dielectric nanoparticles to form a planarized surface. A second nanoparticle layer 1050 may then be disposed on the planarized surface. The interparticle spacing between particles in the array may be at least 200 nm, at least 300 nm, at least 400 nm, greater than 500 nm, etc.

[0115] Figure 10 (c) illustrates an embodiment in which both the first layer 1050 and the second layer 1070 contain metal nanoparticles. The coupling layer may include a dielectric spacer layer, and the first nanoparticle layer 1050 may be deposited over the dielectric spacer layer. A dielectric material 1055 may be deposited in the region between the nanoparticles of the first layer 1050 to create a planarized surface. The dielectric material 1055 may have a refractive index less than 1.5, less than 1.75, less than 2.0, etc. The second nanoparticle layer 1070 may be deposited over the first layer 1050, for example, on the planarized surface. The first and second nanoparticle layers 1050 / 1070 may be separated by a dielectric material with a thickness less than 100 nm, less than 50 nm, less than 20 nm, etc.

[0116] Figure 10(d) illustrates an embodiment in which both the first nanoparticle layer 1060 and the second nanoparticle layer 1065 contain dielectric nanoparticles. In this embodiment, the first layer 1060 may be deposited directly above the top surface of the reinforcement layer 1020, wherein the dielectric material 1055 fills the spaces between the dielectric nanoparticles. In some embodiments, the outcoupling layer may comprise a very thin (e.g., less than 2 nm) dielectric spacer layer, and the first dielectric nanoparticle layer 1060 is disposed above this dielectric spacer layer. Figure 10 (e) illustrates an embodiment in which the first nanoparticle layer 1050 comprises metal nanoparticles and the second nanoparticle layer 1060 comprises dielectric nanoparticles. In this embodiment, for example, combined with Figure 10 As discussed in (c), the metal nanoparticle layer 1050 can be deposited above the dielectric spacer layer. The dielectric material 1055 can be deposited in the region between the metal nanoparticles 1050 and form a planarized top surface. The properties of the dielectric material can be related to... Figure 10 Similar to (c) described above. The dielectric nanoparticle layer 1060 can be deposited on top of the planarized surface.

[0117] Quasi-periodic arrays exhibiting the Mohr effect can also be formed by stacking more than two nanoparticle arrays of different periods. For ease of understanding, the described example refers to three nanoparticle arrays. However, more than three nanoparticle arrays can be used. The arrays are stacked to form a stack in the out-of-plane direction. Any of the previously described techniques can be used to stack nanoparticle arrays to produce layers of nanoparticles stacked on top of each other. For example, the first nanoparticle layer may include nanoparticles embedded in a medium to create a planar surface. The second nanoparticle layer may be deposited directly on top of the first nanoparticle layer. A planar surface will be created on the second nanoparticle layer. The third nanoparticle layer may be deposited directly on top of the second nanoparticle layer. A planar surface will be created on the third nanoparticle layer. This process can continue until the desired number of nanoparticle layers are included in the stack. In some embodiments, each array may be separated by a distance of at least 10 nm, at least 25 nm, at least 50 nm, etc., or preferably less than 100 nm in the out-of-plane direction.

[0118] The angular emission profile generated by a moiré array can exhibit emission characteristics similar to those of a quasi-periodic array. In some embodiments, the emission profile can be wider than a Lambertian profile, while in some other embodiments, a device using a moiré array can exhibit multiple emission directions.

[0119] It should be understood that the various embodiments described herein are merely examples and are not intended to limit the scope of the invention. For instance, many of the materials and structures described herein can be substituted with other materials and structures without departing from the spirit of the invention. The claimed invention may therefore include variations of the specific examples and preferred embodiments described herein, as will be apparent to those skilled in the art. It should be understood that various theories regarding why the invention works are not intended to be limiting.

Claims

1. An apparatus comprising: Substrate; First electrode; An emission layer containing organic emission material is disposed above the first electrode; An enhancement layer positioned above the emission layer; and An outcoupling layer disposed above the reinforcing layer, wherein the outcoupling layer comprises an array of nanoparticles, wherein the array comprises a periodic array or a quasi-periodic array.

2. The apparatus of claim 1, wherein the emission profile of the apparatus is tuned according to the selection of array symmetry in the design of a plurality of arrays.

3. The apparatus of claim 2, wherein the array symmetry is selected from the group consisting of at least one of the following: translational symmetry and rotational symmetry.

4. The apparatus of claim 1, wherein the quasi-periodic array comprises an array design without long-range positional order, and wherein the length scale of the short-range positional periodicity is no greater than the plasmon propagation length of the enhancement layer.

5. The apparatus of claim 1, wherein the quasi-periodic array is generated by periodically combining the lattice of the first periodic array within the second periodic array.

6. The apparatus of claim 5, wherein the lattice periodicity within the quasi-periodic array is selected from the group consisting of at least 100 nm, at least 200 nm, at least 300 nm, at least 400 nm, and greater than 500 nm.

7. The apparatus of claim 5, wherein the first periodic array and the second periodic array comprise different lattice periodicities.

8. The apparatus of claim 7, wherein the lattice periodicity is selected from the group consisting of: square lattices, hexagonal lattices, tilted lattices, and rectangular lattices.

9. The apparatus of claim 1, wherein the interparticle spacing between the nanoparticles in the quasi-periodic array is greater than the maximum size of the nanoparticles.

10. The apparatus of claim 9, wherein the interparticle spacing is selected from the group consisting of at least 200 nm, at least 300 nm, at least 400 nm, and at least 500 nm.

11. The apparatus of claim 1, wherein the reinforcing layer comprises a plasmonic material exhibiting surface plasmonic resonance, the surface plasmonic resonance being nonradiatively coupled to the organic emitter and transferring excited-state energy from the organic emitter to a nonradiative mode of the surface plasmonic polariton, wherein the reinforcing layer may be configured to be located at a distance from the organic emitter not exceeding a threshold distance.

12. The apparatus of claim 11, wherein the organic emissive material has a total nonradiative decay rate constant and a total radiative decay rate constant due to the presence of the reinforcing layer, and the threshold distance is the position where the total nonradiative decay rate constant is equal to the total radiative decay rate constant.

13. The apparatus of claim 11, wherein the organic emissive material has a total nonradiative decay rate constant. Total radiation attenuation rate constant The total nonradiative attenuation rate constant attributed to the enhancement layer and the total radiation attenuation rate constant attributed to the enhancement layer ;and The threshold distance is the distance that meets the following conditions: 。 14. A consumer electronic device comprising: Substrate; First electrode; An emission layer containing organic emission material is disposed above the first electrode; The second electrode is positioned above the emission layer; and An outcoupling layer disposed above the reinforcing layer, wherein the outcoupling layer comprises an array of nanoparticles, wherein the array comprises a periodic array or a quasi-periodic array.

15. The consumer device of claim 14, wherein the device is at least one type selected from the group consisting of: flat panel displays, curved displays, computer monitors, medical monitors, televisions, billboards, lights for internal or external lighting and / or signaling, head-up displays, fully transparent or partially transparent displays, flexible displays, rollable displays, foldable displays, stretchable displays, laser printers, telephones, cellular phones, tablet computers, tablet phones, personal digital assistants (PDAs), wearable devices, laptop computers, digital cameras, camcorders, viewfinders, microdisplays with a diagonal of less than 2 inches, 3D displays, virtual reality or augmented reality displays, vehicles, automotive displays, video walls comprising multiple displays tiled together, theater or stadium screens, and signs.

Images