Organic electroluminescent device

Abstract

The invention relates to an organic electroluminescent device. Embodiments of the disclosed subject matter provide a device comprising a plasmon phosphorescent organic light emitting device (PHOLED) having an anode and a cathode having a thickness of about 5-100 nm. An emission stack is disposed between the anode and the cathode and configured to generate excitons, and the emission stack has a phosphorescent first emission layer comprising an organic phosphorescent first emission material. The device includes an enhancement layer comprising a plasmon material exhibiting surface plasmon resonance, the plasmon material being at least non-radiatively coupled to the organic phosphorescent first emissive material and transferring excited state energy from the first emissive material to a non-radiative mode of the plasmon material. The device is configured to produce a temperature rise of less than 1 DEG C per 2.26 mW / cm2 operating power applied to the device.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. patent application serial number 63 / 592,659, filed on October 24, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to emitting devices including organic emitting devices, including emitting devices including plasmonic phosphorescent organic light emitting devices (PHOLEDs), and techniques for manufacturing the emitting devices. Background Art

[0004] Optoelectronic devices utilizing organic materials are becoming increasingly popular for many reasons. Many materials used to make the devices are relatively inexpensive, so organic optoelectronic devices have the potential to have cost advantages over inorganic devices. In addition, the inherent properties of organic materials (e.g., their flexibility) can make them more suitable for specific applications, such as manufacturing 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 have performance advantages over conventional materials. For example, the wavelength at which the organic emissive layer emits light can generally be easily adjusted with appropriate dopants.

[0005] OLEDs utilize organic thin films that emit light when 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. Pat. 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 capable of phosphorescent emission is full-color displays. Industry standards for such displays require pixels suitable for emitting specific colors (called "saturated" colors). Specifically, these standards require saturated red, green, and blue pixels. Alternatively, OLEDs can be designed to emit white light. In conventional liquid crystal displays, an absorption filter is used to filter the emission from a white backlight to produce red, green, and blue emissions. The same technology can also be used for OLEDs. White OLEDs can be single EML devices or stacked structures. Colors can be measured using CIE coordinates well known in the art. Another application of phosphorescent molecules capable of phosphorescent emission is to manufacture lighting or illumination panels configured to emit monochrome, white, or color-adjustable light.

[0007] As used herein, the term "organic" includes polymeric materials and small molecule organic materials that can be used to make organic optoelectronic devices. "Small molecule" refers to any organic material that is not a polymer, and a "small molecule" may actually be quite large. In some cases, a small molecule may include repeating units. For example, the use of a long chain alkyl group as a substituent 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 part of a dendritic polymer, which consists of a series of chemical shells built on the core part. The core part of a dendritic polymer can be a fluorescent or phosphorescent small molecule emitter. A dendritic polymer can be a "small molecule", and all dendritic polymers currently used in the field of OLEDs are considered to be small molecules.

[0008] As used herein, "top" means farthest from the substrate, while "bottom" means closest to the substrate. Where a first layer is described as being "disposed "above" a second layer, the first layer is disposed farther from the substrate. Unless it is specified that the first layer is "in contact with" the second layer, there may be other layers between the first and second layers. For example, a cathode may be described as being "disposed "above" an anode even though various organic layers are present between the cathode and the anode.

[0009] As used herein, "solution processable" means capable of being dissolved, dispersed or transported in and / or deposited from a liquid medium in the form of a solution or suspension.

[0010] When a ligand is believed to directly contribute to the photosensitive property of an emissive material, the ligand may be referred to as "photosensitive." When a ligand is believed not to contribute to the photosensitive property of an emissive material, the ligand may be referred to as "ancillary," but the ancillary ligand may alter the properties of the photosensitive ligand.

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

[0012] As used herein, and as one skilled in the art would generally understand, a first work function is "greater than" or "higher than" a second work function if the first work function has a higher absolute value. Because work functions are typically measured as negative numbers relative to the vacuum level, this means that a "higher" work function is more negative. On a conventional energy level diagram with the vacuum level at the top, a "higher" work function is illustrated as being farther away from the vacuum level in a downward direction. Thus, the definition of HOMO and LUMO energy levels follows different rules than work functions.

[0013] Layers, materials, regions, and devices may be described herein with reference to the color of light they emit. Generally, as used herein, an emissive region described as producing light of a particular color may include one or more emissive layers disposed above each other in a stacked manner.

[0014] As used herein, a "red" layer, material, region or device refers to a layer, material, region or device that emits light in the range of about 580-700nm or whose emission spectrum has the highest peak in the region. 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 about 500-600nm; 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 about 400-500nm; a "yellow" layer, material, region or device refers to a layer, material, region or device that has an emission spectrum with a peak wavelength in the range of about 540-600nm; 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 about 490-520nm; 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 about 570-620nm. In some arrangements, separate regions, layers, materials, regions, or devices may provide separate "dark blue" and "light blue" light. As used herein, in arrangements that provide separate "light blue" and "dark blue" components, the "dark blue" component refers to a component having a peak emission wavelength that is at least about 4 nm less 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 may vary for some configurations. The peak emission wavelength of the "light green" component is in the range of about 520 nm to 560 nm, and the peak emission wavelength of the "deep green" or "dark green" component is in the range of about 500 nm to 520 nm, but these ranges may vary for some configurations. The near infrared ("NIR") component has a peak emission wavelength in the range of approximately 700 to 1800 nm. Similarly, a color changing layer refers to a layer that converts or modifies light of another color into light having a wavelength designated for that color. For example, a "red" filter refers to a filter that forms light having a wavelength in the range of approximately 580-700 nm. In general, there are two types of color changing layers: color filters that modify the spectrum by removing undesirable wavelengths of light, and color changing layers that convert higher energy photons to lower energy. A "color" component refers to a component that, when activated or used, produces or otherwise emits light having a specific color as previously described. 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 previously described when activated within the device.

[0015] As used herein, emissive materials, layers, and regions may be distinguished from each other and from other structures based on the spectrum initially produced by the material, layer, or region, rather than the light ultimately emitted by the same or different structure. Initial light generation is typically the result of a change in energy levels that results in photon emission. For example, an organic emissive material may initially produce blue light, which may be converted to red, green, or yellow light by a color filter, quantum dots, or other structure, such that the complete emissive stack or sub-pixel emits red, green, or yellow light. In this case, the initial emissive material or layer may be referred to as the "blue" component, even if the sub-pixel is a "red," "green," or "yellow" component.

[0016] In some cases, it may be preferred to describe the color of a component, such as the color of an emitting region, a sub-pixel, a color changing layer, etc., in terms of 1931 CIE coordinates. For example, a yellow emitting material may have multiple peak emission wavelengths, one in or near the edge of a "green" region, and one in or near the edge of a "red" region, as previously described. Thus, as used herein, each color term also corresponds to a shape in the 1931 CIE coordinate color space. Shapes in the 1931 CIE color space are 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 may be defined as follows:

[0017]

[0018] Further details regarding OLEDs and the definitions set forth above can be found in US Pat. 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] According to one embodiment, a device may include a plasmon phosphorescent organic light emitting device (PHOLED) having an anode and a cathode having a thickness of about 5-100 nm. The device may include an emission stack disposed between the anode and the cathode and configured to generate excitons, the emission stack having a phosphorescent first emission layer, the phosphorescent first emission layer comprising an organic phosphorescent first emission material. The device may include an enhancement layer comprising a plasmon material exhibiting a surface plasmon resonance, the plasmon material at least non-radiatively coupling to the organic phosphorescent first emission material and transferring excited state energy from the first emission material to a non-radiative mode of the plasmon material. The device may be configured to provide a 2.26 mW / cm2 boost for each 2.26 mW / cm2 applied to the device. 2 The operating power produces a temperature rise of less than 1°C.

[0021] The plasmonic material of the enhancement layer can exhibit a surface plasmon resonance that at least non-radiatively couples to the phosphorescent first emitting material and transfers excited state energy from the first emitting material to the plasmonic material.

[0022] The common enhancement layer may be positioned less than a threshold distance from the organic phosphorescent first emitting material.

[0023] The enhancement layer may be disposed at a distance less than a threshold distance from the organic phosphorescent first emitting material. The organic phosphorescent first emitting material may have a total non-radiative decay rate constant Total radiative decay rate constant The total nonradiative decay rate constant attributed to the reinforcement layer is and the total radiative decay rate constant attributed to the enhancement layer The enhancement layer is disposed at a position not exceeding a threshold distance from the phosphorescent first emission layer. The threshold distance is the distance when the following conditions are satisfied

[0024]

[0025] In the device, INC*OUTC>1-INC, where INC can be the fraction of excitons generated in at least one emission layer of the emission stack that couple to one or more plasmon modes in the cathode, and OUTC can be the fraction of plasmons that are outcoupled in the form of photons emitted outside the emission stack.

[0026] In the device, INC can be the number of excitons from the emission layer of the emission stack that are coupled to the plasmon mode in the cathode divided by the total number of excitons in the emission layer of the emission stack, and OUTC can be the number of plasmons of photons outcoupled outside the emission stack divided by the total number of excitons in the emission layer of the emission stack.

[0027] The cathode of the device may include an Ag film, wherein the thickness of the cathode is between 5 nm and 45 nm.

[0028] The device can be configured to deliver 11.4 mW / cm 2 or 13.6mW / cm 2 When operated at a power density of less than 5°C, the operating temperature rise is not more than 5°C.

[0029] The device may be a display, and the plasmonic PHOLED may be configured to have an operating temperature rise of no more than 1°C for a luminance increase of 268 nits for a display luminance increase or a luminance increase of 320 nits for a display luminance increase.

[0030] The device may include an outcoupling layer.

[0031] The device may be a display and may be configured to operate at a white point brightness of greater than 1,340 nits, greater than 1,400 nits, greater than 1,500 nits, and / or greater than 1,600 nits.

[0032] The emission stack of the device may include at least two emission layers disposed above each other.

[0033] The device can have an INC ≥ 80%, where INC can be the fraction of excitons generated in at least one emissive layer of the emissive stack that couple to one or more plasmon modes in the cathode.

[0034] The device can have an INC ≥ 60%, where INC can be the fraction of excitons generated in at least one emissive layer of the emissive stack that couple to one or more plasmon modes in the cathode.

[0035] The emission stack can be configured to have a first peak photon density inside the emission stack that is lower than a second peak photon density outside the emission stack when the device emits light. The first peak photon density inside the emission stack can be lower than half of the second peak photon density outside the emission stack.

[0036] The external quantum efficiency of the plasmonic PHOLED of the device can be greater than 35%.

[0037] A first emission layer of at least one emission layer of the device may have an excited state duration selected from the group consisting of: less than 20%, 25%, 30%, 35%, 40%, 45%, less than 50%, 55% or 60% of a predetermined excited state lifetime value.

[0038] A plasmonic PHOLED configured to have an external quantum efficiency greater than 35% has an excited state lifetime that differs by less than 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55% and / or 60% of a predetermined excited state lifetime value.

[0039] The emitting stack of the plasmonic PHOLED may have at least a first side and a second side, wherein the device may be configured to emit light from the first side and may be configured to have a Lambertian emission profile of the light.

[0040] The anode of the emitting stack may be transparent.The device may have an optical transparency of greater than 40% or greater than 60% over the visible spectrum.

[0041] The anode of the emitting stack may be reflective.

[0042] The plasmonic PHOLED of the device may have an external quantum efficiency greater than 35% and have incoupling of excitons from at least one emissive layer into plasmon modes in the cathode greater than 60%. The anode of the device may be reflective.

[0043] The device may be a lighting panel and / or a full color display.

[0044] The thickness of the cathode of the device may be 5-200 nm, 5-150 nm, 5-100 nm, 5-75 nm, 5-60 nm, 5-45 nm, 15-45 nm, and / or 25-35 nm.

[0045] The device can be configured to provide a 2.72 mW / cm 2 The operating power produces a temperature rise of less than 1°C.

[0046] According to one embodiment, a consumer electronic device may include a plasmonic phosphorescent organic light emitting device (PHOLED) having an anode and a cathode having a thickness of about 5-100 nm. The consumer electronic device may include an emission stack disposed between the anode and the cathode and configured to generate excitons, the emission stack having a phosphorescent first emission layer, the phosphorescent first emission layer comprising an organic phosphorescent first emission material. The consumer electronic device may include an enhancement layer comprising a plasmonic material exhibiting surface plasmon resonance, the plasmonic material at least non-radiatively coupling to the organic phosphorescent first emission material and transferring excited state energy from the first emission material to a non-radiative mode of the plasmonic material. The consumer electronic device may be configured to provide a 2.26 mW / cm2 boost for every 2.26 mW / cm2 applied to the device. 2 The operating power produces a temperature rise of less than 1°C.

[0047] The consumer electronic device may be at least one of the following: a flat panel display, a curved display, a computer monitor, a medical monitor, a television, a sign, a light for interior or exterior lighting and / or signaling, a head-up display, a fully or partially transparent display, a flexible display, a rollable display, a foldable display, a stretchable display, a laser printer, a telephone, a cellular phone, a tablet computer, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a microdisplay having a diagonal of less than 2 inches, a 3D display, a virtual reality or augmented reality display, a vehicle, an in-vehicle display, a video wall comprising multiple displays tiled together, a theater or stadium screen and / or a sign. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 An organic light-emitting device is demonstrated.

[0049] Figure 2 An inverted organic light-emitting device without a separate electron transport layer is demonstrated.

[0050] Figure 3 A graph showing the ratio of photons outside to inside a device calculated as a function of incoupling fraction for two different outcoupling efficiencies in accordance with an embodiment of the disclosed subject matter is shown.

[0051] Figure 4 is a graph showing the dependence of plasmon-to-photon outcoupling efficiency on incoupling according to embodiments of the disclosed subject matter to meet performance criteria of (a) greater peak photon density outside the organic stack and (b) external quantum efficiency (EQE) > 35%.

[0052] Figure 5 is a graph showing the calculated outcoupling efficiency as a function of the incoupling efficiency according to an embodiment of the disclosed subject matter, for either of the following two conditions: (1) EQE>35%, or (2) there are more photons outside the device than inside the device.

[0053] Figure 6 The photon density relative to the incoupling efficiency is shown for both inside and outside the device for two different outcoupling efficiencies in accordance with an embodiment of the disclosed subject matter.

[0054] Figure 7 Qualitative plots of radiative decay rate constants attributed to surface plasmon polaritons (SPP) modes and non-radiative decay rate constants attributed to SPP modes as a function of the distance of a light-emitting material from a metal film are presented in accordance with an embodiment of the disclosed subject matter. Figure 7Also shown is a graph of the ratio of the total radiative rate constant to the non-radiative rate constant of the system as a function of the distance of the light-emitting material from the metal film, which is controlled by the rate constant attributed to the SPP mode, according to an embodiment of the disclosed subject matter.

[0055] Figure 8 Shown are graphs of quantum yield as a function of distance of a light-emitting material from a metal enhancement film, and two threshold distances identified in accordance with embodiments of the disclosed subject matter.

[0056] Fig. 9 An illustrative plasmonic phosphorescent organic light emitting device (PHOLED) according to an embodiment of the disclosed subject matter is presented. DETAILED DESCRIPTION

[0057] In general, an OLED comprises at least one organic layer disposed between and electrically connected to an anode and a cathode. When an electric current is applied, the anode injects holes and the cathode injects electrons into the organic layer. The injected holes and electrons each migrate toward the oppositely charged electrode. 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 light emission mechanism, light is emitted. In some cases, the exciton can be localized on an excimer or an excited complex. Non-radiative mechanisms (such as thermal relaxation) may also occur, but are generally considered undesirable.

[0058] The first OLEDs used emissive molecules that emitted light from a singlet state ("fluorescence"), as disclosed, for example, in US Pat. No. 4,769,292, which is incorporated by reference in its entirety. Fluorescence emission typically occurs in a time frame of less than 10 nanoseconds.

[0059] Recently, OLEDs with emissive materials that emit light from triplet states ("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", Appl. Phys. Lett., Vol. 75, Nos. 3, 4-6 (1999) ("Baldo-II"), which are incorporated by reference in their entirety. Phosphorescence is described in more detail in U.S. Pat. No. 7,279,704, Columns 5-6, which is incorporated by reference.

[0060] Figure 1 An organic light-emitting device 100 is shown. The figure is not necessarily drawn to scale. The 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. The device 100 can be manufactured by depositing the layers in sequence. The properties and functions of these various layers and example materials are described in more detail in US 7,279,704, columns 6-10, which is incorporated by reference.

[0061] More examples of each of these layers can be obtained. For example, a flexible and transparent substrate-anode combination is disclosed in U.S. Patent No. 5,844,363, which is incorporated by reference in its entirety. An example of a p-doped hole transport layer is m-MTDATA doped with F4-TCNQ at a molar ratio of 50:1, as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, which is incorporated by reference in its entirety. Examples of emissive and host materials are disclosed in U.S. Patent No. 6,303,238 to Thompson et al., which is incorporated by reference in its entirety. An example of an n-doped electron transport layer is BPhen doped with Li at a molar ratio of 1:1, as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, which is incorporated by reference in its entirety. U.S. Patent Nos. 5,703,436 and 5,707,745, which are incorporated by reference in their entirety, disclose examples of cathodes including composite cathodes having a thin layer of a metal (e.g., Mg:Ag) with an overlying transparent, conductive, sputter-deposited ITO layer. The theory and use 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 by reference in their entirety. Examples of injection layers are provided in U.S. Patent Application Publication No. 2004 / 0174116, which is incorporated 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 by reference in its entirety. Barrier layer 170 can be a single or multilayer barrier layer and can cover or surround other layers of the device. Barrier layer 170 can also surround substrate 110, and / or it can be disposed between the substrate and other layers of the device. Barrier layers may also be referred to as encapsulants, encapsulation layers, protective layers, or permeation barriers, and generally provide protection against the penetration of moisture, ambient air, and other similar materials through the other layers of the device. Examples of barrier layer materials and structures are provided in U.S. Pat. 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 by reference in its entirety.

[0062] Figure 2An inverted OLED 200 is shown. The device includes a substrate 210, a cathode 215, an emissive layer 220, a hole transport layer 225, and an anode 230. Device 200 can be manufactured by depositing the layers in order. Because the most common OLED configuration has a cathode disposed above the anode, and device 200 has cathode 215 disposed below anode 230, 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 device 200. Figure 2 An example is provided of how some layers may be omitted from the structure of device 100 .

[0063] Figure 1 and 2 The simple layered structures described in are provided by way of non-limiting examples, and it should be understood that embodiments of the present 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 completely omitted based on design, performance and cost factors. Other layers not specifically described may also be included. Materials other than the specifically described materials can be used. Although many of the examples provided herein describe the various layers as including a single material, it should be understood that a combination of materials (such as a mixture of a host and a dopant) or more generally a mixture can be used. In addition, the layers can have various sub-layers. 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 emissive layer 220, and can be described as a hole transport layer or a hole injection layer. In one embodiment, the OLED can be described as having an "organic layer" disposed between the cathode and the anode. This organic layer can include a single layer, or can further include, for example, Figure 1 and 2 Multiple layers of said different organic materials.

[0064] Structures and materials not specifically described may also be used, such as OLEDs containing polymeric materials (PLEDs), such as disclosed in U.S. Pat. No. 5,247,190 to Friend et al., which is incorporated by reference in its entirety. By way of another example, an OLED having a single organic layer may be used. OLEDs may be stacked, such as described in U.S. Pat. No. 5,707,745 to Forrest et al., which is incorporated by reference in its entirety. OLED structures may deviate from Figure 1 and 2For example, the substrate may include angled reflective surfaces to improve out-coupling, such as a mesa structure as described in U.S. Pat. No. 6,091,195 to Forrest et al., and / or a pit structure as described in U.S. Pat. No. 5,834,893 to Bulovic et al., which are incorporated by reference in their entirety.

[0065] In some embodiments disclosed herein, an emissive layer or material, such as Figure 1-2 The emission layer 135 and the emission layer 220 shown in the figure, respectively, may include quantum dots. The emission layer may use different emission display technologies. Such 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 in accordance with the understanding of a technician in the field, the "emission layer" or "emission material" disclosed herein may include organic emission materials and / or emission materials containing quantum dots or equivalent structures. In general, the emission layer includes an emission material within a host matrix. Such an emission layer may only include quantum dot materials that convert light emitted by a separate emission material or other emitter, or it may also include a separate emission material or other emitter, or it may directly emit light by applying an electric current. Similarly, a color change layer, a color filter, an up-conversion or down-conversion layer or structure may include a material containing quantum dots, but such a layer may not be considered an "emission layer" as disclosed herein. Typically, an "emissive layer" or material is one that emits initial light based on injected charge, where the initial light can be altered by another layer, such as 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 absorption and down-conversion of the initial light emitted by the emissive layer into 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 external to the OLED device, such as above or below an electrode of the OLED device.

[0066] Unless otherwise specified, any of the layers of the various embodiments may be placed, arranged or deposited by any suitable method. For organic layers, preferred methods include thermal evaporation, inkjet (as described in U.S. Pat. Nos. 6,013,982 and 6,087,196, incorporated by reference in their entirety), organic vapor phase deposition (OVPD) (as described in U.S. Pat. No. 6,337,102 to Forrest et al., incorporated by reference in their entirety) and deposition by organic vapor jet printing (OVJP) (as described in U.S. Pat. No. 7,431,968, incorporated by reference in their entirety). Other suitable deposition methods include spin coating and other solution-based processes. Solution-based processes are preferably carried out in nitrogen or an inert atmosphere. For other layers, preferred methods include thermal evaporation. Preferred patterning methods include deposition through a mask, cold welding (as described in U.S. Pat. Nos. 6,294,398 and 6,468,819, which are incorporated 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 make it compatible with a specific deposition method. For example, branched or unbranched substituents such as alkyl and aryl groups, preferably containing at least 3 carbons, may be used in small molecules to enhance their ability to withstand solution processing. Substituents having 20 or more carbons may be used, and 3 to 20 carbons are a preferred range. Materials having asymmetric structures may have better solution processability than materials having symmetric structures because asymmetric materials may have a lower tendency to recrystallize. Dendritic polymer substituents may be used to enhance the ability of small molecules to withstand solution processing.

[0067] The device manufactured according to the embodiment of the present invention may further optionally include a barrier layer. One purpose of the barrier layer is to protect the electrode and the organic layer from exposure to harmful substances in the environment including moisture, steam and / or gas. The barrier layer can be deposited on the substrate, the electrode, deposited under the substrate, the electrode or deposited next to the substrate, the electrode, or deposited on any other part (including the edge) of the device. The barrier layer may include a single layer or multiple layers. The barrier layer can be formed by various known chemical vapor deposition techniques, and may include a composition with a single phase and a composition with multiple phases. Any suitable material or material combination can be used for the barrier layer. The barrier layer may be combined with an inorganic compound or an organic compound or both. The preferred barrier layer comprises a mixture of a polymeric material and a non-polymeric material, as described in U.S. Patent No. 7,968,146, PCT Patent Application No. PCT / US2007 / 023098 and No. PCT / US2009 / 042829, which are incorporated herein by reference in their entirety. In order to be considered a "mixture", the aforementioned polymeric material and non-polymeric material constituting the barrier layer should be deposited under the same reaction conditions and / or deposited simultaneously. The weight ratio of polymeric material to non-polymeric material can be in the range of 95:5 to 5:95. The polymeric material and non-polymeric material can be produced from the same precursor material. In one example, the mixture of polymeric material and non-polymeric material consists essentially of polymeric silicon and inorganic silicon.

[0068] In some embodiments, at least one of the anode, cathode, or a new layer disposed above the organic emission layer is used as an enhancement layer. The enhancement layer includes a plasmon material exhibiting a surface plasmon resonance, the plasmon material non-radiatively couples to the emitter material, and transfers excited state energy from the emitter material to a non-radiative mode of a surface plasmon polariton. The enhancement layer is provided at a threshold distance not exceeding the organic emission layer, wherein due to the presence of the enhancement layer, the emitter material has a total non-radiative decay rate constant and a total radiative decay rate constant, and the threshold distance is the distance at which the total non-radiative decay rate constant is equal to the total radiative decay rate constant. In some embodiments, the enhancement layer includes a plasmon material exhibiting a surface plasmon resonance, the plasmon material non-radiatively couples to at least a phosphorescent first emission material and transfers excited state energy from the first emission material to a surface plasmon resonance of the plasmon material. In some embodiments, the OLED further includes an outcoupling layer. In some embodiments, the outcoupling layer is disposed above the enhancement layer on the opposite side of the organic emission layer. In some embodiments, the outcoupling layer is disposed on the opposite side of the emission layer from the enhancement layer, but still outcouples energy from the surface plasmon mode of the enhancement layer. The outcoupling layer scatters energy from the surface plasmon polaritons. In some embodiments, this energy is scattered into free space in the form of photons. In other embodiments, energy is scattered from the surface plasmon mode of the device into other modes, such as but not limited to an organic waveguide mode, a substrate mode, or another waveguide mode. If the energy is scattered into a non-free space mode of the OLED, other outcoupling schemes may be incorporated to extract the energy into free space. Outcoupling methods for substrate modes or waveguide modes include but are not limited to lenses, diffusers, and directly buried diffractive elements. In some embodiments, one or more intervening layers may be disposed between the enhancement layer and the outcoupling layer. Examples of intervening layers may be dielectric materials, including organics, inorganics, perovskites, oxides, and may include stacks and / or mixtures of these materials.

[0069] The enhancement layer modifies the effective properties of the medium in which the emitter material resides, resulting in any or all of the following: reduced emissivity, modification of the emission line shape, changes in emission intensity versus angle, changes in robustness of the emitter material, changes in the efficiency of the OLED, and reduced efficiency decay of the OLED device. Placing the enhancement layer on the cathode side, the anode side, or both produces an OLED device that exploits any of the above effects. In addition to the specific functional layers described in the various OLED examples mentioned herein and shown in the figures, the OLED according to the present invention may also include any of the other functional layers typically found in OLEDs.

[0070] The enhancement layer may be composed of a plasmonic material, an optically active metamaterial, or a hyperbolic metamaterial. As used herein, a plasmonic material is a material whose real part of the dielectric constant crosses zero in the visible or ultraviolet region of the electromagnetic spectrum. In some embodiments, the plasmonic material includes 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. In general, a metamaterial is a medium composed of different materials, where the function of the medium as a whole is different from the sum of its material parts. Specifically, we define an optically active metamaterial as a material having both a negative dielectric constant and a negative magnetic permeability. On the other hand, a hyperbolic metamaterial is an anisotropic medium in which the permittivity or magnetic permeability has different signs for different spatial directions. Optically active metamaterials and hyperbolic metamaterials are strictly distinguished from many other photonic structures, such as distributed Bragg reflectors ("DBRs"), because the medium should be uniform in the direction of propagation for the length scale of the wavelength of light. Using terms that are understood by those skilled in the art: the dielectric constant of the metamaterial in the direction of propagation can be described approximately by the effective medium. Plasmonic materials and metamaterials provide a way to control light propagation that can enhance OLED performance in many ways.

[0071] 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-periodically, or randomly, or has sub-wavelength-sized features arranged periodically, quasi-periodically, or randomly. In some embodiments, the wavelength-sized features and sub-wavelength-sized features have sharp edges.

[0072] In some embodiments, the outcoupling layer has wavelength-sized features that are periodically, quasi-periodically, or randomly arranged, or has sub-wavelength-sized features that are periodically, quasi-periodically, or randomly arranged. In some embodiments, the outcoupling layer may be composed of a plurality of nanoparticles, and in other embodiments, the outcoupling layer is composed of a plurality of nanoparticles disposed above a material. In these embodiments, the outcoupling can be tuned by at least one of: 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 enhancement layer, and / or changing the material of the enhancement layer. The plurality of nanoparticles of the device may be formed of at least one of: a metal, a dielectric material, a semiconductor material, a metal alloy, a mixture of dielectric materials, a stack or layering of one or more materials, and / or a core of one type of material coated with a shell of a different type of material. In some embodiments, the outcoupling 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 can have additional layers disposed above them. In some embodiments, the polarization of the emission can be tuned using the outcoupling layer. Changing the dimensionality and periodicity of the outcoupling layer can select a class of polarizations that preferentially outcouple to air. In some embodiments, the outcoupling layer also acts as an electrode of the device.

[0073] In embodiments of the disclosed subject matter, a device may include an enhancement layer disposed above an emission region of at least one subpixel configured to have Lambertian emission and / or at least one subpixel having a microcavity configured for direct emission, as described in detail below. In at least some of such 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 at which the total non-radiative decay rate constant is equal to the total radiative decay rate constant. In some such embodiments, a device may include an outcoupling layer disposed above the enhancement layer on opposite sides of the emission region.

[0074] It is believed that the internal quantum efficiency (IQE) of fluorescent OLEDs can exceed the 25% spin statistics limit through delayed fluorescence. As used herein, there are two types of delayed fluorescence, namely P-type delayed fluorescence and E-type delayed fluorescence. P-type delayed fluorescence is produced by triplet-triplet annihilation (TTA).

[0075] In some embodiments, the emitting material and / or compound in the layer in the OLED may be used as a phosphorescent sensitizer, wherein one or more layers in the OLED may include an acceptor in the form of one or more fluorescent and / or delayed fluorescent emitters. In some embodiments, the compound may be used as a component of an excited complex, which is used as a sensitizer. As a phosphorescent sensitizer, the compound may be able to transfer energy to an acceptor, and the acceptor may emit energy or further transfer energy to the final emitter. The acceptor concentration may be in the range of 0.001% to 100%. The acceptor may be in the same layer as the phosphorescent sensitizer or in one or more different layers. In some embodiments, the acceptor may be a TADF emitter. In some embodiments, the acceptor may be a fluorescent emitter. In some embodiments, the emission may be generated by any one or all of the sensitizer, the acceptor, and / or the final emitter.

[0076] On the other hand, the above-mentioned E-type delayed fluorescence does not rely on the collision of two triplets, but 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-triplet gap. Thermal energy can activate the transition from the triplet state back to the singlet state. This type of delayed fluorescence is also called thermally activated delayed fluorescence (TADF). A notable feature 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 the non-radiative decay of the triplet state, the fraction of backfilling the singlet excited state may reach 75%. The total singlet fraction can be 100%, far exceeding the spin statistical limit of electrically generated excitons.

[0077] E-type delayed fluorescence characteristics can be found in excitation complex systems or single compounds. Without being bound by theory, it is believed that E-type delayed fluorescence requires that the luminescent material has a small singlet-triplet energy gap (ΔES-T). Organic, metal-free donor-acceptor luminescent materials may be able to achieve this. The emission of these materials is usually characterized by donor-acceptor charge transfer (CT) type emission. The spatial separation of HOMO and LUMO in these donor-acceptor type compounds usually leads to a small ΔES-T. These states may be related to CT states. Typically, donor-acceptor luminescent materials are constructed by connecting an electron donor moiety (e.g., an amino or carbazole derivative) to an electron acceptor moiety (e.g., a six-membered aromatic ring containing N).

[0078] Devices manufactured according to embodiments of the present invention may be incorporated into a wide variety of electronic component modules (or units), which may be incorporated into a variety of electronic products or intermediate components. Examples of electronic products or intermediate components include display screens, lighting devices (such as discrete light source devices or lighting panels), etc. that can be utilized by end-user product manufacturers. The electronic component module may optionally include drive electronics and / or a power supply. Devices manufactured according to embodiments of the present invention may be incorporated into a wide variety of consumer products, which have one or more electronic component modules (or units) incorporated therein. A consumer product comprising an OLED is disclosed, wherein the OLED includes a compound of the present disclosure in an organic layer in the OLED. The consumer product should include any kind of product containing one or more light sources and / or a certain type of visual display. Some examples of such consumer products include flat panel displays, curved displays, computer monitors, medical monitors, televisions, billboards, lights for interior or exterior lighting and / or signaling, heads-up displays, fully 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, video cameras, viewfinders, microdisplays with a diagonal of less than 2 inches, 3D displays, virtual reality or augmented reality displays, vehicles, in-vehicle displays, video walls comprising multiple displays tiled together, theater or stadium screens, and signage. Various control mechanisms can be used to control devices made according to the present invention, including passive matrices and active matrices. Many of the devices are intended to be used in a temperature range that is 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.).

[0079] 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 employ the materials and structures. More generally, organic devices such as organic transistors can employ the materials and structures.

[0080] 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.

[0081] In some embodiments, the OLED further comprises a layer having a delayed fluorescent emitter. In some embodiments, the OLED comprises an RGB pixel arrangement or a white plus color filter pixel arrangement. 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 having 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 having 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.

[0082] In some embodiments of the emission region, the emission region further comprises a body.

[0083] In some embodiments, the compound causing light generation can be an emissive dopant. In some embodiments, the compound can generate emission via phosphorescence, fluorescence, thermally activated delayed fluorescence (ie, TADF, also known as E-type delayed fluorescence), triplet-triplet annihilation, or a combination of these processes including phosphorescence-sensitized fluorescence.

[0084] The OLEDs disclosed herein may be incorporated into one or more of consumer products, electronic component modules, and lighting panels.The organic layer may be an emissive layer, and the compound may be an emissive dopant in some embodiments, while the compound may be a non-emissive dopant in other embodiments.

[0085] 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 small role in charge transport. In some embodiments, the host may include a metal complex. The host may be an inorganic compound.

[0086] Combination with other materials

[0087] The materials described herein as being suitable for use in a particular layer in an organic light-emitting device can be used in combination with a variety of other materials present in the device. For example, the emissive dopants disclosed herein can be used in combination with a wide variety of hosts, transport layers, barrier layers, injection layers, electrodes, and other layers that may be present. 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.

[0088] The various emissive and non-emissive layers and arrangements disclosed herein may use different materials. Examples of suitable materials are disclosed in U.S. Patent Application Publication No. 2017 / 0229663, which is incorporated by reference in its entirety.

[0089] Conductive dopants:

[0090] The charge transport layer can be doped with a conductivity dopant to substantially change its charge carrier density, which in turn will change its conductivity. The conductivity is increased by generating charge carriers in the matrix material, and depending on the type of dopant, a change in the Fermi level of the semiconductor can also be achieved. The hole transport layer can be doped with a p-type conductivity dopant, and an n-type conductivity dopant is used in the electron transport layer.

[0091] HIL / HTL:

[0092] The hole injection / transport material used in the present invention is not particularly limited, and any compound may be used as long as the compound is generally used as a hole injection / transport material.

[0093] EBL:

[0094] An electron blocking layer (EBL) can be used to reduce the number of electrons and / or excitons that leave the emissive layer. The presence of such a blocking layer in a device can produce substantially higher efficiency and / or longer lifetime than a similar device lacking a blocking layer. In addition, a blocking layer can be used to confine emission to desired areas of the OLED. In some embodiments, the EBL material has a higher LUMO (closer to the vacuum level) and / or a higher triplet energy than the emitter closest to the EBL interface. In some embodiments, the EBL material has a higher LUMO (closer to the vacuum level) and / or a higher triplet energy than one or more of the hosts closest to the EBL interface. In one aspect, the compound used in the EBL contains the same molecule or the same functional group as used in one of the hosts described below.

[0095] main body:

[0096] The light-emitting layer of the organic EL device of the present invention preferably contains at least a metal complex as a light-emitting material, and may contain a host material using the metal complex as a dopant material. Examples of the host material are not particularly limited, and any metal complex or organic compound may be used as long as the triplet energy of the host is greater than the triplet energy of the dopant. Any host material may be used with any dopant as long as the triplet criterion is satisfied.

[0097] HBL:

[0098] A hole blocking layer (HBL) can be used to reduce the number of holes and / or excitons that leave the emissive layer. The presence of such a blocking layer in a device can result in substantially higher efficiency and / or longer lifetime than a similar device lacking a blocking layer. In addition, a blocking layer can be used to confine emission to a desired area of ​​the OLED. In some embodiments, the HBL material has a lower HOMO (further from the vacuum level) and / or a higher triplet energy than the emitter closest to the HBL interface. In some embodiments, the HBL material has a lower HOMO (further from the vacuum level) and / or a higher triplet energy than one or more of the hosts closest to the HBL interface.

[0099] ETL:

[0100] The electron transport layer (ETL) may include a material capable of transporting electrons. The electron transport layer may be intrinsic (undoped) or doped. Doping may be used to enhance conductivity. Examples of ETL materials are not particularly limited, and any metal complex or organic compound may be used as long as it is generally used to transport electrons.

[0101] Charge Generation Layer (CGL)

[0102] In a tandem or stacked OLED, the CGL plays a fundamental role in the performance and consists of an n-doped layer and a p-doped layer for injecting electrons and holes, respectively. Electrons and holes are supplied by the CGL and electrodes. The electrons and holes consumed in the CGL are refilled by electrons and holes injected from the cathode and anode, respectively; then, the bipolar current gradually reaches a steady state. Typical CGL materials include n- and p-conductivity dopants used in the transport layer.

[0103] Key parameters for OLED devices can be efficiency and operating lifetime. In recent years, plasmonic OLEDs have been proposed, where excitons in the organic stack of a plasmonic OLED can be quenched by conversion to plasmon polaritons in a suitable cathode metal, and then re-emitted as photons through an outcoupler, such as a nanoparticle-based array on top of a dielectric spacer. This type of device can have additional benefits, such as Lambertian emission, which can reduce color shift and have less brightness roll-off depending on viewing angle.

[0104] In order for the device to be viable from a product requirements perspective, the excited state lifetime can be reduced to extend the operating lifetime of the device, and the external quantum efficiency can meet or exceed the external quantum efficiency of conventional devices (>35% for phosphorescent OLEDs with a single emissive layer). Embodiments of the disclosed subject matter provide plasmonic phosphorescent organic light emitting devices (PHOLEDs) based on reducing the excited state lifetime by at least 2.5 times (which can increase the operating lifetime by more than six (6) times) and having an external quantum efficiency (EQE) exceeding 35%.

[0105] In an embodiment of the disclosed subject matter, the device may include an emissive layer comprising a material having emission by one or more of the following: phosphorescence, fluorescence, thermally activated delayed fluorescence (i.e., TADF (also known as E-type delayed fluorescence)), triplet-triplet annihilation, or a combination of these processes, including phosphorescence-sensitized fluorescence. In addition, an embodiment of the disclosed subject matter may include one or more emissive layers, and each of the one or more emissive layers comprises a material having emission by one or more of the following: phosphorescence, fluorescence, thermally activated delayed fluorescence (i.e., TADF (also known as E-type delayed fluorescence)), triplet-triplet annihilation, or a combination of these processes, including phosphorescence-sensitized fluorescence. In an embodiment comprising more than two emissive layers, each of the more than two emissive layers may comprise a material that emits by the same emission process, some of the same emission processes, or not by the same emission process. In an embodiment of the present invention, a device may include an emissive layer comprising an inorganic emissive material, including but not limited to LEDs, mini LEDs, micro LEDs, and the like.

[0106] In embodiments of the disclosed subject matter, plasmon polaritons and plasmon-exciton-polaritons can be used to reduce excited state duration and / or provide stability. This can reduce the excited state density in the emissive layer (EML) of the plasmon PHOLED and increase the stability of the device. The stability increase can be non-linear as the excited state duration is reduced, indicating that a 2.5-fold (i.e., 2×) reduction in excited state duration can provide greater than a six-fold increase in stability (i.e., a 6× increase).

[0107] With regard to the efficiency of the device, the most widely used application of OLED displays is mobile phone displays. Microcavities can be utilized in mobile phone displays to render saturated colors. Microcavities change the angular emission profile of OLEDs. The emitted power can increase perpendicular to the surface of the OLED and can decrease rapidly at angles other than perpendicular to the surface. The spectrum of the OLED can change with angle. These characteristics may be detrimental to the wider adoption of OLEDs. However, as an alternative to microcavities, plasmonic PHOLEDs can be used, whose efficiency is such that light emitted vertically from a plasmonic device has an efficiency similar to that of normally incident light from a microcavity device. For a Lambertian emitting device, this would correspond to an EQE of about 35% or more for a device with a single emitting layer.

[0108] In conventional OLEDs using microcavity structures or in the case of OLEDs that do not use microcavities, there may be loss paths. These loss paths may include waveguides for photons. In conventional OLEDs, the number of photons inside the device is greater than the number of photons outside the device. However, due to the excitons coupled to the surface plasmon polaritons, the number of photons inside the plasmon device may be less than the number of photons outside the device. An embodiment of the disclosed subject matter provides a device in which the peak photon density outside the organic stack exceeds the peak photon density inside the organic stack in the vertical direction of the substrate. This can be done without using a lens coupled to the substrate, and / or without using a high refractive index substrate optically coupled to a high refractive index lens. The device of the disclosed embodiment can reduce the exciton density in the stack while effectively radiating photons as useful light. In some cases, the peak photon density outside the organic stack may exceed twice the peak photon density inside the organic stack in the vertical direction of the substrate.

[0109] In a conventional bottom-emitting device, the maximum number of photons outside the device can be divided by the photon density inside the device. Assuming an almost zero vertical dipole moment that provides optimal dipole orientation for outcoupled light, about 50% of the photons can be outcoupled to light outside the device. An aluminum (Al) cathode may have about 20% exciton losses, and absorption may have 5% losses. This means that about 25% of the light is captured inside the device. In fact, exciton losses inside the stack can reduce the number of photons outcoupled from the device. As Figure 3 As shown, the number of photons outside the device divided by the number of photons inside the device can exceed ten (10), and for the plasmonic PHOLED devices of the disclosed embodiments, can reach up to twenty (20).

[0110] Losses in the device can be in the form of reduced exciton density or reduced photon density. These losses can affect the ratio of photons outside the device to those inside the device, depending on the exact nature and location of these losses. Exciton losses in the stack can generally reduce the photon density inside and outside the device, while photon losses in the stack may primarily reduce the photon density inside the device.

[0111] The excited state lifetime can be reduced in various ways. For example, the reduction of excited state lifetime can be achieved by placing the EML near the silver cathode. The reduction of excited state lifetime has also been demonstrated using the Purcell effect in microcavities.

[0112] These design criteria for embodiments of the disclosed subject matter can be derived from the following considerations, where INC can be the incoupling of excitons from the emitting layer (EML) into plasmon modes in the cathode, and OUTC can be the outcoupling of plasmons to photons outside the organic stack, where the device EQE = INC*OUTC. In one embodiment, INC can be the number of excitons from the emitting layer of the emitting stack that are coupled to the plasmon modes in the cathode divided by the total number of excitons in the emitting layer of the emitting stack, and OUTC can be the number of plasmons outcoupled to photons outside the emitting stack divided by the total number of excitons in the emitting layer of the emitting stack.

[0113] To ensure that the peak photon density outside the organic stack exceeds the peak photon density inside the organic stack in the vertical direction of the substrate: INC*OUTC>1-INC. Figure 4 and 5 A graph is shown that relates the device design parameter OUTC to INC to meet the following two device design criteria: (1) a photon criterion, where the peak photon density inside the organic stack may be lower than the peak photon density outside the stack; and (2) for devices with a single emissive layer (EML), INC>60% and EQE>35%.

[0114] The plasmonic PHOLEDs of the disclosed subject matter can reduce device temperature rise for any given drive current compared to conventional PHOLEDs. The plasmonic PHOLEDs of the disclosed subject matter can have improved device performance and device lifetime by reducing temperature increase as brightness increases. Reducing the operating temperature of a display is beneficial because it can extend the device operating lifetime.

[0115] In conventional OLEDs, heat is generated in the organic stack between the anode and cathode. This heat is related to (1-outcoupling), where outcoupling is the EQE. That is, the heat may be related to energy put into the device that is not emitted as photons.

[0116] In a plasmonic PHOLED, heat can be generated by losses in two different and separate modes. First, heat can be generated by losses in the organic stack between the anode and cathode, which is related to (1-INC). That is, energy can be put into the device and not coupled into the cathode in a plasmonic form.

[0117] Secondly, in a plasmonic PHOLED, heat can be generated by plasmon losses in both the cathode and the outcoupling layer. This may be because the efficiency in the plasmon outcoupling is less than 100%, so this second loss will be related to INC*(1-OUTC). That is, the losses in the stack are related to (1-INC), and the losses outside are related to INC*(1-OUTC). By consistency, it can be seen that the total loss is the sum of the losses inside and outside the organic stack, which is related to (1-outcoupling), where outcoupling = INC*OUTC, except that in a plasmonic device the losses occur in two different areas of the device, and the outcoupling can be the same or similar to the outcoupling of a conventional device. Embodiments of the disclosed subject matter can reduce the temperature rise in the device for any given total loss. Heat losses in or above the cathode (i.e., outside the organic stack) can be removed by a metal cathode that is configured to have a thickness that provides thermal conductivity. Device stability can depend greatly on temperature. Reducing this temperature rise can greatly improve the operating life of the device.

[0118] To analyze the effect of the cathode on reducing the temperature rise, the results from laser flash analysis of thermal conductivity can be used. In this method, one side of the material can be heated by a heat pulse (from a laser). The thermal conductivity can be determined by measuring the heat rise on the opposite side of the material. For one-dimensional diffusion, the following has been determined:

[0119] α=0.139*d 2 / t (1)

[0120] where α is in cm 2 / s is the thermal diffusivity, d is the distance (thickness) of the sample, and t is the time it takes for the temperature to reach 1 / 2 of the limit value, which can be the steady-state value. This equation can be recalculated to determine the time it takes for the instantaneous heat generation to leave the sub-pixel area.

[0121] Typical displays are 250-500 DPI, which means that the pixels are 100 to 50 microns wide. Although each pixel is usually formed by 3 sub-pixels, a single pixel is assumed in this example. This means that heat generated in the middle of the pixel will have to travel 50 to 25 microns to 'escape' the pixel and not increase the temperature of the OLED. Rearranging equation (1), we find that: t = 0.139*d 2 / α.

[0122] For Ag, use α = 1.65 cm 2 / s, transient heat can leave a typical display area between 0.5 and 2.0 microseconds. This is extremely fast and suggests that the heat generated in the cathode may not raise the temperature in the OLED device. An important aspect is that the Ag cathode is continuous, so that it exhibits a thermal diffusivity similar to bulk Ag. Typical Ag films can be continuous, with a thickness as low as 3-5nm, with a good adhesion layer. Therefore, for Ag, the thickness of the plasmon-active cathode of the device of the disclosed subject matter can range from about 5nm to 200nm, 5nm to 150nm, 5nm to 100nm, 5nm to 75nm, 5nm to 60nm, 5nm to 45nm, 15nm to 45nm, and preferably can range from 25nm to 35nm.

[0123] As a Figure of Merit (FOM), the heat generated inside the stack of a plasmonic PHOLED at the same drive current compared to a conventional PHOLED can be equal to (1-INC) / (1-OUTC). Table 1 below provides the FOM percentages based on INC and OUTC percentages:

[0124] INC OUTC FOM 60％ 60％ 63％ 70％ 60％ 52％ 70％ 70％ 59％ 80％ 60％ 38％ 80％ 70％ 45％ 80％ 80％ 56％

[0125] Table 1

[0126] Based on this analysis, embodiments of the disclosed subject matter provide a plasmonic PHOLED where INC ≥ 80%. The thermal rise in the device of the disclosed embodiments may be less than about half at any given current density compared to a non-plasmonic PHOLED display with EQE ≤ 40%, and the thermal rise is at least less than 60% compared to a non-plasmonic PHOLED display with EQE ≤ 40%.

[0127] Given this relationship, the plasmonic PHOLED displays of the disclosed subject matter can have high brightness and / or input power and low operating temperature. For example, these calculations can be based on US 8,766,531, which shows 35.3 mW / cm 2 The input power increases the temperature of the AMOLED display by 26°C.

[0128] Embodiments of the disclosed subject matter provide devices with a maximum display temperature rise of 5° C. This may be based on the fact that for every 5° C increase in lifetime, lifetime is reduced by approximately 25%. This may be a reasonable limit on operating lifetime that does not cause visual degradation of the display that may affect use.

[0129] Assuming that the temperature rise is linear with the input power, 5°C may correspond to less than 6.8 mW / cm for a conventional PHOLED display. 2 The plasmonic device of the disclosed subject matter can achieve the same temperature rise at twice (2×) the input power, which, assuming FOM < 50%, can correspond to 13.6 mW / cm for an operating temperature rise of less than 5°C. 2 The plasmonic device of the disclosed subject matter can achieve the same temperature rise as a non-plasmonic device at 1.67 times the input power, which, assuming FOM < 60%, can correspond to 11.4 mW / cm for an operating temperature rise of less than 5°C. 2 .

[0130] Demonstrated at 500cd / m 2 Table 2 The white point operation of the plasmonic PHOLED consumes less than 4.4 mW / cm 2 Using the analysis from Table 2, for 13.6 mW / cm 2 A temperature rise of less than 5°C can be achieved, which may correspond to a full display white point of approximately 1600 nits with a FOM < 50%. Using the analysis from Table 2, for 11.4 mW / cm 2 A temperature rise of less than 5°C can be achieved, which may correspond to a full display white point of approximately 1340 nits with a FOM < 60%.

[0131] Assumptions Green Component = 61.1％ Red Component = 32.6％ Blue component = 6.3％ % pixels turned on 100％ Monitor specifications width 11.5 cm high 5.31 cm brightness 500 <![CDATA[cd / m 2 ]]> CALCS Green brightness = 3,273 Red brightness = 1,746 Blue brightness = 338 Green Power 0.085 W Red Power 0.117 W Blue Power 0.064 W Total Power 0.267 W 4.36 <![CDATA[mW / cm 2 ]]>

[0132] Table 2

[0133] Embodiments of the disclosed subject matter may provide a device including a plasmonic phosphorescent organic light emitting device (PHOLED) having an anode and a cathode having a thickness of about 5-60 nm. An exemplary plasmonic PHOLED device 300 is shown in Fig. 9 , which may include a substrate 310 , a cathode 315 , an emission stack 320 , an enhancement layer 325 , and an anode 330 . Fig. 9 Only exemplary arrangements are shown, and other arrangements of plasmonic PHOLED devices may be used.

[0134] The device (e.g., device 300) may include an emission stack (e.g., emission stack 320) disposed between an anode (e.g., anode 330) and a cathode (e.g., cathode 315) and configured to generate excitons, the emission stack having a phosphorescent first emission layer comprising an organic phosphorescent first emission material. The device may include an enhancement layer (e.g., enhancement layer 325) comprising a plasmon material exhibiting a surface plasmon resonance, the plasmon material at least non-radiatively coupling to the organic phosphorescent first emission material and transferring excited state energy from the non-radiatively coupled organic phosphorescent first emission material to a non-radiative mode of a surface plasmon polariton. The device may be configured to generate an exciton for every 2.72 mW / cm applied to the device. 2 The operating power produced a temperature rise of less than 1°C, or even for every 2.26 mW / cm applied to the device. 2 An operating power of 1000W produces a temperature rise of less than 1° C. The enhancement layer may be positioned less than a threshold distance from the organic phosphorescent first emitting material.

[0135] The organic phosphorescent first emitting material may have an overall non-radiative decay rate constant Total radiative decay rate constant The total nonradiative decay rate constant attributed to the reinforcement layer is and the total radiative decay rate constant attributed to the enhancement layer The enhancement layer is disposed at a position not exceeding a threshold distance from the phosphorescent first emission layer. The threshold distance is the distance when the following conditions are satisfied

[0136]

[0137] The increased emission rate constant of an OLED emitter depends largely on the distance of the emitter from the enhancement layer. When the emitter is closer than the threshold distance, achieving better performance requires moving the light-emitting material closer to the enhancement layer. In order to achieve better OLED performance, the preferred distance from the enhancement layer to the organic emission layer ("EML") containing the emission material is no more than 100nm, more preferably no more than 60nm, and most preferably no more than 25nm. In some embodiments and for manufacturability reasons, the distance between the enhancement layer and the EML may be required to be 5-100nm, more preferably 5-60nm, and most preferably 5-25nm. Achieving this desired distance between the EML and the enhancement layer may require providing one or more of the various functional OLED layers between the EML and the enhancement layer so that the EML is not in direct contact with the enhancement layer. For example, a hole injection layer may be included between the enhancement layer and the emission material layer to reduce the operating voltage of the OLED. Various functional OLED layers may optionally be provided between the EML and the enhancement layer. The minimum threshold distance in this embodiment is about 5nm, because this is approximately the minimum thickness required for various materials to form a working functional OLED layer.

[0138] Understanding the advantages of using the non-radiative mode of SPPs and controlling the distance between the EML and the enhancement layer to be no greater than a threshold distance starts with the decay rate constant of the luminescent material. For any light emitter, the quantum yield (QY) of photons can be expressed as the ratio of the radiative decay rate constant to the non-radiative decay rate constant and is well defined as the number of photons emitted per excited state:

[0139]

[0140] in is the sum of all radiation processes, and is the sum of all non-radiative processes. For an isolated emitter in free space, the molecular radiative and non-radiative decay rate constants can be defined as k 0 辐射 and k 0 非辐射 For an isolated molecule, the quantum yield (QY°) is:

[0141]

[0142] However, in optoelectronic devices (such as OLEDs), there are multiple other processes that affect the total radiative and non-radiative decay rate constants. Some of these are energy transfers to radiative and non-radiative decay modes of surface plasmons in plasmonic materials (such as metals). These modes become important when the luminescent material is near the plasmonic material. This can cause the values ​​of both the total radiative decay rate constant and the total non-radiative decay rate constant to increase in the presence of the plasmonic material. These additional processes can be specifically explained in the quantum yield:

[0143]

[0144] in and are the radiative decay rate constant and the non-radiative decay rate constant of the light emitter when interacting with SPPs, respectively.

[0145] Figure 7 It is shown in and Qualitative plot of the distance of the light emitter from an enhancement layer (such as a metal film). For distances close to the enhancement layer, Will be Item dominance, and Will be Therefore, Figure 7 It also describes the total radiative and non-radiative decay rates. Figure 7 is shown on the right axis of , which is the total radiation decay rate constant The total nonradiative decay rate constant The ratio of Figure 3 As shown on the left axis of , the two plasmon-based decay rate constants have different functional dependencies on the distance of the emitter from the metal layer (in this case, 1 / r^6 for the non-radiative rate and 1 / r^3 for the radiative rate). The different dependencies on the distance from the enhancement layer produce a range of distances at which the radiative decay rate constant is a maximum rate constant due to the interaction with the surface plasmons. For distances within this particular range, the photon yield increases compared to that of an isolated molecule without an enhancement layer, increasing the QY. This is illustrated in the graph Figure 8 In the figure, the quantum yield is plotted as a function of the distance of the luminescent material from the metal film. After the value of the non-radiative decay rate constant becomes close to the radiative decay rate, the QY begins to decrease, resulting in a QY peak at a certain distance.

[0146] For a given pair of luminescent material and enhancement layer, there may be a total non-radiative decay rate constant and a total radiative decay rate constant. As the luminescent material layer becomes closer to the enhancement layer, the non-radiative decay rate constant increases more rapidly than the radiative decay rate constant. At a certain distance, the total non-radiative decay rate constant of the luminescent material in the presence of the enhancement layer may be equal to the total radiative decay rate constant of the luminescent material in the presence of the enhancement layer. This may be referred to herein as the threshold distance 1. The threshold distance 1 may be the distance of the luminescent layer from the enhancement layer at which the following statement holds true:

[0147]

[0148] For distances closer to the enhancement layer than the threshold distance 1, the total non-radiative decay rate may be greater than the radiative decay rate, and the quantum yield may be less than 0.5 or 50%. For these distances, the rate at which energy leaves the light emitter may increase even more as the non-radiative decay rate constant exceeds the radiative decay rate constant. Enhancement layer to emitter distances less than or equal to the threshold distance 1 may satisfy the following conditions:

[0149]

[0150] For distances greater than a threshold distance 1, the total radiative decay rate constant can be greater than the total non-radiative decay rate constant, however, the quantum yield of the luminescent material is reduced compared to the case when the enhancement layer is not present. Thus, the light emitter can still be quenched, a process that is typically avoided in optoelectronic devices, but can be part of embodiments of the disclosed subject matter.

[0151] The distance of the emitter from the enhancement layer at which quenching begins may be defined herein as a threshold distance 2. At this distance, the QY of the light emitter may be the same in the presence and absence of the enhancement layer. As the light emitter moves closer to the enhancement layer, the QY may decrease. The threshold distance 2 may be the distance of the light emitting layer from the enhancement layer at which the following statements hold true:

[0152] QY 0 =QY (6),

[0153] [1] QY 0 is the intrinsic quantum yield of the luminescent material, and QY is the quantum yield in the presence of the enhancement layer. This yields the following expression when considering the radiative and non-radiative decay rate constants of the plasmonic material attributed to the enhancement layer:

[0154]

[0155] [2] Solution The following expression for the decay rate constant at the threshold distance 2 was obtained:

[0156]

[0157] [3] Conceptually, the threshold distance 2 can be more easily understood from the value of the quantum yield being equal to the value of the quantum yield of the luminescent material in the absence of an enhancement layer. Figure 8 .

[0158] Regardless of considering threshold distance 1 or threshold distance 2, the physical value of the threshold distance may depend on a variety of factors, including the frequency of the surface plasmon polaritons, the oscillator strength of the light-emitting material, and the dielectric constant of the light-emitting material layer. Therefore, by selecting a set of suitable materials for the organic light-emitting material and the plasmon material of the enhancement layer, the threshold distance can be adjusted.

[0159] The cathode of the device may include an Ag film, wherein the thickness of the cathode is 5nm-45nm. Alternatively, for Ag, the thickness of the cathode may be in the range of 5nm up to 200nm, 5nm up to 150nm, 5nm up to 100nm, 5nm up to 75nm, 5nm up to 60nm, 5nm up to 45nm, 15nm up to 45nm, and may preferably be in the range of 25nm up to 35nm. In some embodiments, the device may include an outcoupling layer. The emission stack of the device may include at least two emission layers arranged above each other. The device may be a lighting panel and / or a full-color display.

[0160] The device can be configured to deliver 11.4 mW / cm 2 or 13.6mW / cm 2The device may be a display and the plasmonic PHOLED may be configured to have an operating temperature rise of no more than 1°C for a display brightness increase of 268 nits and a display brightness increase of 320 nits. The device may be a display and may be configured to operate at a white point brightness of greater than 1,340 nits, greater than 1,400 nits, greater than 1,500 nits, and / or greater than 1,600 nits. Red, green, and / or blue light may be mixed in a display to produce white light at a fixed standard or color temperature such as D65, where the color temperature of the white light may be, for example, 6500K.

[0161] In the device, INC*OUTC>1-INC, where INC can be the fraction of excitons generated in at least one emitting layer of the emitting stack that couple to one or more plasmon modes in the cathode, and OUTC can be the fraction of plasmons that are outcoupled in the form of photons emitted outside the emitting stack. The device can have INC≥80%. In some embodiments, the device can have INC≥60%.

[0162] The emission stack can be configured to have a first peak photon density inside the emission stack that is lower than a second peak photon density outside the emission stack when the device emits light. The first peak photon density inside the emission stack can be lower than half of the second peak photon density outside the emission stack.

[0163] The external quantum efficiency of the plasmon PHOLED of the device can be greater than 35%. In some embodiments, the first emission layer of at least one emission layer of the device may have an excited state duration that is less than 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, or 60% of a predetermined excited state duration. This predetermined value can be used for a conventional emission layer having an aluminum cathode and an electron transport layer having a thickness of at least 35 nm. In some embodiments, the difference in excited state lifetime of the plasmon PHOLED configured to have an external quantum efficiency greater than 35% is less than 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, and / or 60% of the predetermined excited state lifetime value.

[0164] In some embodiments, a first emitting layer of at least one emitting layer of the device may have an excited state duration that is less than 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, or 60% of a predetermined excited state value or duration. In one embodiment, the predetermined value or duration is the excited state lifetime of the emitter at 1% in PMMA. A thin film of the emitter in PMMA is formed on quartz by drop casting a filtered solution of 1% emitter with PMMA in toluene onto a pre-cleaned quartz substrate. Transient data is measured using a 335nm NanoLED pulsed excitation source by a variety of methods including time-correlated single photon counting (TCSPC).

[0165] As used herein, a Lambertian profile may have a diffuse emission of light whose intensity is independent of emission angle to within 10% or 20%.

[0166] The anode of the emission stack can be transparent. As used throughout, the emission stack can be transparent by at least 30%, at least 40%, or at least 60% for any wavelength longer than 400nm in the visible region of the electromagnetic spectrum. The device can be greater than 40% or greater than 60% optically transparent for any wavelength longer than 400nm in the visible region of the electromagnetic spectrum, or have an overall or average transparency in excess of 40% in the visible spectrum. In some embodiments, the anode of the emission stack can be reflective. As used throughout, a surface can be reflective when reflecting at least 20% or at least 30% of any wavelength longer than 400nm in the visible region of the electromagnetic spectrum.

[0167] The plasmonic PHOLED of the device may have an external quantum efficiency of greater than 35% and may have an incoupling of excitons from at least one emitting layer to a plasmon mode in the cathode of greater than 60%. The device may have an optical transparency of greater than 40% or greater than 60% over the visible spectrum. The anode of the device may be reflective. The emitting stack of the plasmonic PHOLED may have at least a first side and a second side, wherein the device is configured to emit light from the first side and is configured to have a Lambertian emission profile of light.

[0168] Embodiments described herein may be found in devices having pixels comprising one or more sub-pixels. Embodiments described herein may be found in at least one of the one or more sub-pixels. In a first embodiment, at least one sub-pixel may be in a side-by-side (SBS) architecture. In an SBS architecture, at least one or more emission layers of each sub-pixel in a pixel are different from the emission layers of another sub-pixel in the pixel. Typically, a "red" sub-pixel will have a red emission layer, and the red emission layer emits red light, and the sub-pixel emits red light. In one embodiment, there may be no color filter or color-changing layer in the SBS architecture, but this is not necessary and a color filter or color-changing layer may be used. In a second embodiment, at least one sub-pixel may be in a stacked architecture. In a stacked architecture, at least one or more emission layers are shared between two or more sub-pixels in a pixel. Typically, this is used in a white plus color filter / color-changing layer architecture, where the emission layer in the pixel produces "white" light, and different color filters / color-changing layers are arranged for the sub-pixels in the pixel to produce the desired color. For example, a stack can produce "white", a first sub-pixel can have a red color filter / color changing layer, so the first sub-pixel will produce red light, and a second sub-pixel can have a green color filter / color changing layer, so the second sub-pixel will produce green light. Any color filter / color changing layer can be used to produce any color light. In addition, stacking does not necessarily need to produce "white" light, and any color of light can be produced. Devices that are a hybrid of both SBS and stacked architectures can be manufactured to produce pixel / sub-pixel designs that include some or all of the described embodiments. Embodiments of the present invention may be included in one or more SBS or stacked pixel / sub-pixel designs.

[0169] It should be understood that the various embodiments described herein are by way of example only, and are not intended to limit the scope of the present invention. For example, other materials and structures may be used to replace many materials and structures described herein without departing from the spirit of the present invention. The present invention as required may therefore include variations of specific examples and preferred embodiments described herein, as will be apparent to those skilled in the art. It should be understood that the various theories about why the present invention works are not intended to be restrictive.

Claims

1. A device comprising: A plasmon phosphorescent organic light-emitting device PHOLED, comprising: anode; a cathode having a thickness of about 5-100 nm; an emitting stack disposed between the anode and the cathode and configured to generate excitons, the emitting stack comprising a phosphorescent first emitting layer comprising an organic phosphorescent first emitting material; an enhancement layer comprising a plasmonic material exhibiting surface plasmon resonance, said plasmonic material non-radiatively coupling to at least said organic phosphorescent first emitting material and transferring excited state energy from said first emitting material to a non-radiative mode of said plasmonic material, wherein the device is configured to provide a voltage of 2.26 mW / cm for each 2.26 mW / cm 2 The operating power produces a temperature rise of less than 1°C.

2. The device of claim 1, wherein the enhancement layer is disposed at a position less than a threshold distance from the organic phosphorescent first emitting material.

3. The device of claim 1, wherein the organic phosphorescent first emitting material has a total non-radiative decay rate constant Total radiative decay rate constant The total nonradiative decay rate constant attributed to the reinforcement layer is and the total radiative decay rate constant attributed to the enhancement layer The enhancement layer is disposed at a position no more than a threshold distance from the phosphorescent first emission layer, and the threshold distance is a distance when the following conditions are satisfied 4. The device according to claim 1, wherein INC*OUTC>1-INC, in INC is the fraction of excitons generated in at least one emissive layer of the emissive stack that couple to one or more plasmon modes in the cathode, and OUTC is the fraction of plasmons that are outcoupled in the form of photons emitted outside the emitting stack.

5. The device of claim 1, wherein the cathode comprises an Ag film, wherein the cathode has a thickness of 5 nm to 45 nm.

6. The device of claim 1, wherein the device is configured to produce an operating temperature rise of no more than 5°C when operated at a power density selected from the group consisting of: 11.4 mW / cm 2 and 13.6mW / cm 2 .

7. The device of claim 1, wherein the device is a display, and wherein the plasmonic PHOLED is configured to have an operating temperature rise of no more than 1°C for a brightness selected from the group consisting of: a 268 nits increase in display brightness and a 320 nits increase in display brightness.

8. The device of claim 1, wherein the device is a display and is configured to operate at a white point brightness selected from the group consisting of: greater than 1,340 nits, greater than 1,400 nits, greater than 1,500 nits, and greater than 1,600 nits.

9. The device of claim 1, wherein the plasmonic PHOLED has an external quantum efficiency greater than 35%.

10. The device of claim 1, wherein a first emission layer of the at least one emission layer has an excited state duration selected from the group consisting of: less than 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55% or 60% of a predetermined excited state duration.

11. The device of claim 1 , wherein the plasmonic PHOLED has an external quantum efficiency greater than 35% and has an incoupling of excitons from the at least one emissive layer to plasmon modes in the cathode greater than 60%.

12. A consumer electronic device comprising: A plasmon phosphorescent organic light-emitting device PHOLED, comprising: anode; a cathode having a thickness of about 5-100 nm; an emitting stack disposed between the anode and the cathode and configured to generate excitons, the emitting stack comprising a phosphorescent first emitting layer comprising an organic phosphorescent first emitting material; an enhancement layer comprising a plasmonic material exhibiting surface plasmon resonance, said plasmonic material at least non-radiatively coupling to said organic phosphorescent first emitting material and transferring excited state energy from said first emitting material to a non-radiative mode of said plasmonic material, wherein the device is configured to provide a voltage of 2.26 mW / cm for each 2.26 mW / cm 2 The operating power produces a temperature rise of less than 1°C.

13. A consumer electronic device according to claim 12, wherein the device is of at least one type selected from the group consisting of: a flat panel display, a curved display, a computer monitor, a medical monitor, a television, a billboard, a light for interior or exterior lighting and / or signaling, a head-up display, a fully transparent or partially transparent display, a flexible display, a rollable display, a foldable display, a stretchable display, a laser printer, a telephone, a cellular phone, a tablet computer, a tablet phone, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a video camera, a viewfinder, a microdisplay with a diagonal of less than 2 inches, a 3D display, a virtual reality or augmented reality display, a vehicle, an in-vehicle display, a video wall comprising multiple displays tiled together, a theater or stadium screen, and a sign.

14. The device of claim 1, wherein the cathode has a thickness selected from at least one of the group consisting of 5-200 nm, 5-150 nm, 5-100 nm, 5-75 nm, 5-60 nm, 5-45 nm, 15-45 nm, and 25-35 nm.

15. The device of claim 1, wherein the device is configured to provide a power supply to the device for every 2.72 mW / cm 2 The operating power produces a temperature rise of less than 1°C.

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