TW201342681A - Organic light emitting device and method of producing - Google Patents

Abstract

The invention relates to an organic light emitting device, in a layered structure, comprising a substrate, a bottom electrode, a top electrode, wherein the bottom electrode is closer to the substrate than the top electrode, an electrically active region, the electrically active region comprising one or more organic layers and being provided between and in electrical contact with the bottom electrode and the top electrode, a light emitting region provided in the electrically active region, and a roughening layer, the roughening layer being provided as non-closed layer in the electrically active region and providing an electrode roughness to the top electrode by rough-e-ning the top electrode on at least one an inner side facing the electrically active region and an outer side of the top electrode facing away from the electrically active region. Furthermore, a further organic light emitting device, and a method of producing an organic light emitting device are provided. (Fig. 1)

Description

Organic light emitting device and method of manufacturing same

The present invention relates to an organic light-emitting device and a method of producing the same.

Organic semiconductors are used to produce simple electronic components (such as resistors, diodes, field effect transistors) and optoelectronic components such as organic light-emitting devices (such as organic light-emitting diodes (OLEDs) and many other components). The industrial and economic significance of organic semiconductors and their devices is reflected in the increased number of devices using organic semiconducting active layers, as well as the increase in industries that focus on this topic.
Organic semiconductor devices are made of layers; such organic semiconductor layers mainly comprise conjugated organic compounds, which may be small molecules such as monomers or oligomers, polymers, copolymers, conjugates. a copolymer with a non-conjugated block, a fully or partially interlinked layer, an agglomerate structure, or a brush-like structure. Devices made with different types of compounds, in different layers or mixed together (for example, made of polymers and small molecular layers) are also referred to as polymer-small molecule composite devices. Organic light-emitting diodes (OLEDs) are preferably made of small molecules because the deposition techniques involved in fabricating small-molecule organic light-emitting diodes can produce multilayer structures.
Since 1987, research teams and industrial organizations around the world have begun to spend a lot of effort to improve the performance of organic light-emitting diodes, especially the performance of small-molecule organic light-emitting diodes. One of the initial discussions was to find a suitable organic semiconductor material made of small molecules that could form a homogeneous layer. To date, industrially used charge carrier transport materials are morphologically stable at least to 85 ° C, and typical materials have glass transition temperatures above 100 ° C. At the same time, these materials are subject to a range of other needs, such as high transparency in the visible light spectrum and good charge transfer capability.
Most of the good performance electronic or hole transport materials are relatively high cost materials, mainly due to their complex synthetic approach; this is a problem to be solved.
Another problem to be solved is the improvement in the outcoupling efficiency of the organic light-emitting diode to be used for illumination. A typical organic light-emitting diode has the disadvantage that only about 25% of the produced light is emitted from the device. Approximately 50% of the light remains in the internal mode in the organic layer configuration between the reflective and semi-transmissive electrodes. In addition, 20% is lost due to total reflection in the substrate because the light inside the organic light-emitting diode is formed in an optical medium having a refractive index of about 1.6 to 1.8. When the light is impinging on an optical medium having a lower refractive index, such as another layer in an organic light emitting diode stack, a substrate on which the organic light emitting diode is formed, or one of the electrodes, if Total reflection occurs when the incident angle exceeds a certain value. To enhance the optical outcoupling, several different techniques are used, such as the microlens array described in document US 2010/0224313 A1. However, such technologies need to be further developed because their light extraction efficiency is still far below 100%.
In order to use organic light-emitting diodes in the field of illumination and display, it is therefore necessary to use suitable optical outcoupling methods that can be further incorporated into the process in a less expensive manner. For lighting applications, assuming that a square centimeter of organic light-emitting diode area must be able to cost only a few cents (cents), it can be used to make its application economically reasonable. However, this also means that it is only possible to consider increasing the optical outcoupling in a particularly inexpensive way. At present, organic light-emitting diodes based on so-called small molecules (SM) are processed by the aid of thermal evaporation in a vacuum. In general, organic light-emitting diodes are composed of two to twenty layers all deposited by individual heated vapor. If the optical outcoupling can now be significantly enhanced by a single layer of a single heated vapor deposition layer, the cost conditions of the optical outcoupling method can be met in any case. The same is true for a small molecule-polymer composite organic light-emitting diode.
In the case of applying an organic light-emitting diode as a light-emitting element, it is further required to have a large area of the device. For example, if an organic light emitting diode operates at a luminance of 1000 cd/m ² , an area of several square meters is required to illuminate an office space.

It is an object of the present invention to provide an organic light-emitting device which has improved efficiency (out-of-optical coupling efficiency) for light outcoupling of light generated in a light-emitting region.
This problem is solved by the devices according to items 1 and 12 of the independent patent application, respectively. At the same time, a method of producing an organic light-emitting device according to item 13 of the independent patent application is also provided. The subsidiary items correspond to the preferred embodiments.
According to an idea, an organic light-emitting device comprising a layered structure is provided. The layered structure includes a substrate, a bottom electrode, a top electrode, and an electrically active region, wherein the bottom electrode is closer to the substrate than the top electrode. The electrically active region comprises one or more organic layers and is provided between and in electrical contact with the bottom electrode and the top electrode. A light emitting region is provided in the electrically active region. A roughened layer is provided as a non-closed layer in the electrically active region. The term "non-closed" as used herein refers to a layer made of a roughened structure that protrudes from the underlying layer and separated from each other by a space that does not contain a roughened structure. There may be a flat, very thin ground plane in the space free of the roughened structure, which has the same chemical composition as the roughened structure and has a layer thickness of less than 5 nm. For example, such a ground plane can be one or more layers of molecular monolayers deposited in the rough layer generation process.
And roughening the layer so that the top electrode is provided with an electrode roughening portion by roughening the top electrode facing an inner side of the electrical active region and at least one of an outer side of the top surface of the electrical active region .
The top electrode roughening portion may comprise a roughened inner surface structure on the inner side of the top electrode facing the electrically active region. The top electrode roughening portion may comprise a roughened outer surface structure on the outer side of the top electrode. Viewed from above the electrode, the roughened inner surface structure and the roughened outer surface structure may substantially overlap.
According to another concept, an organic light-emitting device comprising a layered structure is provided. The layered structure includes a substrate, a bottom electrode, a top electrode, and an electrically active region, wherein the bottom electrode is closer to the substrate than the top electrode. The electrically active region comprises one or more organic layers and is provided between and in electrical contact with the bottom electrode and the top electrode, and a light emitting region is provided in the electrical active region. A roughened layer is provided between the substrate and the bottom electrode as a non-closed electrically inactive layer, by roughening the bottom electrode on the inner side of one of the electrically active regions and the bottom electrode is not on the outside of one of the electrically active regions At least one of the roughening layers at least the bottom electrode is provided with an electrode roughening. For the bottom electrode, the outer electrode side faces the substrate. For this device, the roughened layer also provides the electrode with an electrode roughening on at least one of the inner side facing the electrically active region and the outer side of the top electrode non-positive active region. In addition to the roughened layer below the bottom electrode, another roughened layer may be provided in the electrically active region. The other roughened layer is provided in accordance with one or more specific embodiments described in connection with a roughened layer that produces an electrode roughening for the top electrode.
Due to the non-closed structure of the roughened layer, this layer does not completely cover the underlying layer. An island or particle structure can be provided that includes islands/particles of material separated by areas not covered by the roughened structure. These areas may contain no material for the rough layer. The area of the material that does not contain the roughened layer can be provided by the holes present in the roughened layer.
The organic light-emitting device can be provided with more than one layer of roughening. More than one layer of roughening layer may be provided in the electrically active region. A plurality of layers of roughening layers may be provided above and/or below the light emitting regions.
The electrode roughening caused by the roughening layer can be provided with a light reflecting surface structure having reflected (e.g., diffused) light. The structure of the roughened layer itself reflects the light generated in the device. Alternatively, the structure of the roughened layer itself may be substantially free of active light reflection.
One or more layers deposited directly on the roughened layer in the electrically active region may be provided as a closed layer. Alternatively, the layers can be a non-closed layer wherein the particles forming the roughened layer provide an iceberg structure. The structure of the roughened layer extends through one or more layers deposited directly on the roughened layer.
The roughened structure of the electrode has a dimension that can be a thickness level of the electrode layer. The individual electrodes may be roughened only at the locations where the coarse layer particles are present below, otherwise they are flat. The surface roughness can be measured by, for example, a leveling instrument (e.g., Dektak) or an electron microscope cross-sectional image of the device.
The thickness of the electrode provided with the roughened portion produced by the roughened layer may be provided to have a thickness that is many more than the nominal thickness of the roughened layer.
The roughened layer may be provided with a plurality of separate particles (islands) randomly distributed over an underlying layer on which the roughened layer is deposited. The roughened layer is also referred to as a "grain layer." The plurality of separator particles can be provided in random directions, distances between each other (space between the particles), and/or particle size. The separator particles distributed on the lower layer provide an island-like structure for the rough layer. The size of the particles may fall within the wavelength range of visible light, preferably the wavelength range of light emitted by the organic light-emitting device, which may be the wavelength in the organic medium surrounding the particles, or the wavelength in the particulate material.
The particles of the roughened layer may have a lateral dimension of from about 50 nanometers to about 500 nanometers, and/or one of from about 3 nanometers to about 50 nanometers (preferably from about 3 nanometers to about 15 nanometers). height. The particle density inside the organic light-emitting device may be from 5 to 50 particles per square micrometer, preferably from 10 to 30 particles per square micrometer. These particles may have a dimension of up to 1000 nm. Those dimensions may be provided for Mie scattering, which preferably occurs at objects of visible light wavelength (between 450 nm and 700 nm) divided by the diameter of the refractive index of the surrounding organic material. .
The top electrode can be provided on the top layer of an electrically active region which is roughened by a roughened layer provided below the top layer. The top electrode can be in direct contact with the top layer. In other embodiments, one or more layers may be provided between the top electrode and the top layer of the electrically active region. The top electrode can be made of a single layer, or a plurality of electrode layers.
The top electrode can be provided directly on the roughened layer.
The top layer can be a combined illuminating and electron transporting layer. The top layer (provided as a single layer or multiple layers) is a closed layer. Alternatively, the top layer can be a non-closed layer wherein the particles forming the roughened layer provide an iceberg structure. This iceberg structure causes direct contact between the top electrode and the iceberg area.
A roughened layer can be provided between the light emitting region and the top electrode.
A roughened layer can be provided between the light emitting region and the bottom electrode. In the case of more than one layer of roughening, a roughened layer may be provided above the light emitting region, and another layer of roughening may be provided below the light emitting region.
The roughened layer can be provided to have a nominal layer thickness of from about 3 nanometers to about 50 nanometers, preferably from about 3 nanometers to about 15 nanometers. The thickness of the roughened layer is the nominal thickness, which is typically calculated from the mass deposited on a particular area divided by the density of the material. For example, in vacuum heated vapor deposition VTE, the nominal thickness is the value indicated by the thickness monitoring device. The particles of the roughened layer may grow on a surface of the underlying layer which are separated from one another and do not join to form a closed layer.
At the same time, the nominal thickness of the roughened layer can also be measured by atomic force microscopy (AFM).
The roughened layer can be provided on or overlying an electrically doped charge carrier transport layer. The roughened layer may be sandwiched between two electrically doped charge carrier transport layers, the two electrically doped layers being holes and/or electron transport layers. The top layer can be a single layer that is electrically doped, or a plurality of electrically doped sublayers. A roughened layer can be provided on a luminescent layer.
The roughened layer may be provided between and in direct contact with the electron transport layer and the cathode, or between the electromotive transport layer and the anode. The transport layer is electrically doped. The roughened layer can be undoped.
The roughened layer can be made of a self-crystallizing material. The roughened layer made of the self-crystallized material may be disposed adjacent to the hole transport layer, which may be in direct contact with the hole transport layer. Thereby, the light outcoupling of light can be increased. Alternatively, the roughened layer made of self-crystalline material can be disposed on the electron transport side of the device, particularly adjacent to the electron transport layer.
In order to maximize the out-of-light coupling from the organic light-emitting device, it is necessary to minimize internal absorption and to perform light extraction in the waveguide mode and the surface plasmon mode. To handle these optical modes, the roughened layer provides an improvement in the structure of conventional flat-like organic light-emitting devices. In a conventional organic light-emitting device, two flat electrodes are deposited on a flat substrate with a flat organic layer interposed therebetween. In this configuration, the waveguide mode (i.e., the mode of light propagation in the organic layer and possibly also in a translucent electrode (e.g., ITO)) and the surface plasmon mode (on the surface of a generally metallic electrode) The light propagation mode in the excimer is easily coupled to the emitter in the organic light emitting diode. The light that is carried out in these modes is no longer readily optically coupled to the air mode, which significantly limits the light conversion efficiency of the organic light-emitting device.
The architecture of the organic light-emitting device proposed herein allows for a simple structure of at least one of the top electrode layer and the bottom electrode layer. This type of roughening minimizes plasma loss and enhances the optical outcoupling of the waveguide mode. In this way, the roughened portion of the electrode layer can be realized, which can serve as a scattering center/structure of both the waveguide mode and the surface plasmon mode.
As a result of the use of the roughened layer, not only the optical outcoupling but also the angular correlation of the light emission can be improved. The white light spectrum contains several light color compositions, but typically consists of at least some of the blue, green and red light. Since different wavelengths have different emission characteristics, different colors can be seen in different viewing angles in conventional OLEDs. This can be greatly reduced by the scattering properties of the devices proposed herein.
The roughened layer improves the out-of-plane coupling of the internal mode; it also improves the out-of-plane coupling of the substrate mode. The roughening layer can be used to protect the electronic properties of the OLED from being affected. It is further determined that an additional power gain can be achieved by an optical outcoupling film, which is not achievable in a general optical outcoupling solution (conventional scattering layer). In contrast, in conventional OLEDs with simple conventional scattering layers, there is no power gain if another additional optical outcoupling film is used.
A simple structure is proposed to produce a highly efficient organic light-emitting device without an expensive method (for example, micro-structure of the electrode-side substrate surface or the semiconductor-side electrode surface). A flat (unstructured) bottom electrode can also be used. Microstructuring is understood to mean a structure that has a range of wavelengths of light to affect light.
All of the organic layers in the electrically active region were fabricated by vacuum evaporation (Vucuum thermal evaporation, VTE). Alternatively, all of the organic layers in the stacked layer configuration can be fabricated by means of OVPD. In a preferred embodiment, all of the organic layer and both electrodes are deposited in a vacuum coating process, such as VTE or sputtering.
The roughened layer is formed of an organic material as a vapor deposited layer which can be deposited by heating and evaporation in a vacuum. For this purpose, the material has a vaporization (or sublimation) temperature in vacuum that is lower than the decomposition temperature in vacuum. Alternatively, or in addition, the roughened organic layer can be made by means of OVPD. The roughening layer can be established by, for example, dewetting of a film made by spin coating and subsequent heat treatment (for example, a 5% solution of (spiral-TTB) in anisole). In addition, the degreasing of the nano-grade organic film can also be achieved by condensing the solvent from the gaseous state.
The roughened layer can be formed by gaseous condensation of metal nitride nanoparticles, electroplating deposition, vacuum spraying, photolithography, and printing (eg, microcontact printing of nanoparticle arrays).
The roughened organic layer is preferably made of an organic material having a Tg of less than about 40 degrees Celsius. Preferably, a material free of Tg is used. In this manner, the organic material crystallizes itself during vapor deposition onto the substrate without any further tempering steps, as in conventional VTE systems, the substrate temperature is typically between 20 degrees Celsius and 60 degrees Celsius. Between degrees.
Tg is determined by the way DSC measures. The DSC measurement is performed using a material that is returned to room temperature by means of impingement cooling after melting. The material was then heated at a rate of 10 K/min in the measurement. Of the preferred materials used in the roughened organic layer, no Tg was observed.
The roughened layer is preferably crystallized during vapor deposition. Alternatively, the tempering step can be performed after the layer is completed and before the next layer is deposited.
Other concepts of the present invention will be described in more detail below.
The roughened layer may be covered by a charge carrier transport layer such that charge will flow around the roughened particles; however, they may also be directly covered by the metal electrode. Implementation of such structures can be achieved via the use of p- and n-type doped transport layers, as doping of the charge transport layer can result in possible charge carrier traps (which may form on the surface of the roughened particles) At) to reach saturation.
The separation structure (particles, islands) of the roughened layer preferably exhibits minimal absorption in the visible range to avoid absorptive light loss. The refractive index of the particles is selected such that the waveguide mode scattering at the particles is minimized (ie, the refractive index of the roughened particles should be consistent with the refractive index of the organic layer of the organic light-emitting device) or maximized (ie, It is necessary to maximize the refractive index of the organic layer relative to the organic light-emitting device. In the first case, the waveguide mode is not scattered by the roughened particles, but is only scattered via the roughened portion of the metal electrode. In the latter case, the scattering of the waveguide mode can occur directly from the roughened particles.
The deposited particles of the roughened layer can have a circular shape without any significant tip or edge (which may result in a shortcut formation in the cathode or a poorly roughened profile). The roughened particles may be long spherical, or oblate spheroids, or crystals having well-defined edges (eg, needles, tetrahedra, octagons, etc.). These shapes can be achieved, for example, by de-wetting (due to surface tension). It is also true for the printing process performed under the correct parameter set, appropriate material selection (how to crystallize).
The optical outcoupling method can also be combined with other methods well known to those skilled in the art, such as a microlens array film or a scattering substrate.
The particles of the roughened layer can grow wider than the height (for example, the aspect ratio is 5:1 to 1:1). If these particles are taller than the width, they should have a width to height ratio of 1:1 to 1:5 to avoid interruption or penetration through the top electrode.
The organic light emitting device can be provided with at least one of the following features:
- There is a glass transition temperature of at least 300 K below the melting temperature. Preferably, the material does not have any measurable glass transition temperature at temperatures above room temperature and varies directly from the glassy state to the crystalline state, or is completely unknown in the glassy state.
- For all visible light, there is a high light transmission, which can also be defined as having a low extinction coefficient (less than 0.1).
- No obvious color.
- A HOMO-LUMO energy gap of at least 3 eV.
- The material is transparent in the visible region (optical energy gap > 3 eV).
- there is a LUMO of less than 2.0 eV (absolute) (which is atypical for ETMs used in OLEDs), or a HOMO of greater than 5.5 eV (absolute) (which is for HTMs used in OLEDs) Atypical).
- the molecular mass of the electrically doped organic material used in the transport layer is greater than 200 g/mol and less than 400 g/mol (less than 200 g/mol is a compound with excessive volatility, and greater than 400 g/ The case of mol is a compound which cannot be sufficiently crystallized).
When a dehumidification mechanism is used to form the particles of the roughened layer, the material of the particles may have a high Tg, for example above 85 degrees Celsius, such that it is stable under conventional apparatus operation. An example of a degreasing method is 2,2',7,7'-tetrakis (N,N-di-p-methylphenylamino)-9,9'-ring doubled from anisole solution.芴 layer.
In a specific embodiment, the top electrode is an anode, and the material of the rough layer is an electron transport material (ie, the energy barrier of the hole injected into the HOMO of the scattering layer material is so high that it cannot be in the device. Generate hole transmission). It is particularly surprising that this particular embodiment is fully operational, which illustrates that the material of the scattering layer does not need to have any electronic function in the device.
In another embodiment, the top electrode is a cathode, and the material of the roughened layer is a hole transport material (ie, the energy barrier of electron injection into the LUMO of the scattering layer material is so high that it is not available. In the electronic transmission). This is also surprising as explained above.
For the use of scattering or roughening compounds in the electrically active region of the organic light-emitting device, it is preferred that the rough layer has a nominal layer thickness of less than 50 nm; more preferably less than 10 Nano. If the layer containing the roughening compound is used as a template, it is found that when the roughened layer is disposed between a first and a second electron transporting layer, optimum device performance is obtained, and wherein the roughening is obtained. The nominal thickness of the layer is greater than or equal to 3 nanometers and less than or equal to 30 nanometers, preferably between 5 nanometers and 15 nanometers.
The particle size creates a structure on the electrode of the optical wavelength range in the surrounding organic medium to affect the light. Preferably, the width of the feature (parallel to the plane of the substrate) falls within the range of optical wavelengths in the surrounding organic medium. The height is smaller than the width, for example, a factor of 2 or 3. The particles above the layer as well as the individual features (eg top electrode) are randomly distributed. Generally, the refractive index of an organic medium is generally between 1.7 and 2. In most cases, 1.7 is a good approximation.
The wavelength can also be the wavelength in the particulate material, especially if no layer is present between the roughened layer and the top electrode. Preferably, the particles have at least one dimension between 100 nanometers and 450 nanometers.
The roughened structure can have a size sufficient to affect the plasmonics in the top electrode. The height can be less than the width, for example by a factor of 2 or 3. The particles above the layer and individual features such as the top electrode system are randomly distributed.
In general, organic light-emitting devices (OLEDs) are based on the principle of electroluminescence, in which electron-hole pairs (so-called excited electrons) recombine under light illumination. To this end, the organic light-emitting device is constructed in the form of a sandwich structure in which at least one organic film is disposed between two electrodes as an active material, positive and negative charge carriers are injected into the organic material, and from holes or electrons to A charge of a recombination zone (light-emitting layer) is transferred to the organic layer where the charge carriers recombine into singlet and/or tri-state excited electrons under light illumination. Subsequent recombination of the excited electrons causes luminescence. At least one of the electrodes must be transparent to allow light to exit the component. Typically, the transparent electrodes are composed of conductive oxides called TCOs (transparent conductive oxides) or very thin metal electrodes, although other materials may be used. The starting point for the fabrication of the organic light-emitting device is a substrate on which individual layers of the OLED are deposited. If the electrode closest to the substrate is transparent, the element is referred to as a "bottom-emitting OLED"; and if the other electrode is transparent, the element is referred to as a "top-emitting OLED." The bottom electrode is closer to the substrate than the top electrode. The bottom electrode is formed (deposited) before the top electrode is formed (deposited).
The most reliable and efficient OLEDs are those that contain doped layers. The organic solid can be substantially increased by electrically doping the hole transport layer with a suitable receiving material (p-type doping) and electrically doping the electron transport layer with an appropriate supply material (n-type doping). The charge carrier density (and thus the conductivity). Furthermore, similar to the experience of inorganic semiconductors, it is foreseeable to be based precisely on the application of the p-type and n-type doped layers in the component, otherwise it cannot be inferred. Doped charge carrier transport layer (p-type doping of a hole transport layer carried out by a molecular mixture of a receiving type, n-type doping of an electron transport layer carried out by a molecular mixture of a supply type) in organic light emission The use of the diodes is described in documents US 2008/203406 and US 5,093,698.
The materials used in the layer configuration are conventional materials used in OLEDs, and these materials or mixtures thereof satisfy the functions of the layer, such as an injection layer, a transport layer, an emission layer, a connection unit, and the like. For an illustrative example of such layers and materials, please refer to documents US 2009/045728, US 2009/0009072, EP 1 336 208, and references therein.
The illuminating region is a region made of one or more layers in which excited electrons participating in luminescence are formed, and/or where excited electrons recombine the emitted light. Possible illuminating layers are described, for example, in the documents EP 1 508 176, US 2008/203406, EP 1 705 727, US 6,693,296. Different possible configurations of the luminescent layer in the OLED are described, for example, in EP 1 804 308, EP 1 804 309. In a specific case, the charge carrier injection is highly balanced with the charge carrier transport system, and the OLED can be made in a single layer (EP 1 713 136). In this case, the luminescent layer does not need to have a distinct interface, including illuminating The region where the electrons are excited is a light-emitting layer.
Regarding an organic light-emitting device, a Hole Transport Layer (HTL) is a layer containing a large-gap semiconductor, which is responsible for transmitting a hole from an anode or transmitting a hole from a connection unit (CU) to a light emitting layer (Light emitting layer). Layer, LEL or EML). The HTL is included between the anode and the LEL, or between the hole generating side of the CU and the LEL. The HTL can be mixed with another material, such as a p-type dopant, in which case the HTL is said to be p-type doped. The HTL may contain several layers having different compositions. P-type doping of the HTL reduces its resistivity and avoids individual power losses due to the high resistivity of the undoped semiconductor. The doped HTL can also be used as an optical separator because it can be made very thick, up to 1000 nm or more, and the resistivity is not significantly increased.
Regarding an organic light-emitting device, an electron transport layer (ETL) is a layer containing a large-gap semiconductor, which is responsible for transporting electrons from a cathode or transferring electrons from a connection unit to a light-emitting layer. The ETL is included between the anode and the LEL or between the electron generating side of the connecting unit and the LEL. The ETL can be mixed with another material, such as an n-type dopant, in which case the ETL is said to be n-type doped. ETL can contain several layers with different compositions. The n-type doping of the ETL reduces its resistivity and avoids individual power losses due to the high resistivity of the undoped semiconductor. The doped ETL can also be used as an optical separator because it can be made very thick, up to 1000 nm or more, and the resistivity does not increase significantly.
Other layers typically used in OLED fabrication, such as holes and electron blocking layers, implant layers, excited electron blocking layers, and the like, can also be used.
The most reliable and at the most efficient device is an organic light-emitting device containing an electrically doped layer. The organic solid can be substantially increased by electrically doping the hole transport layer with a suitable receiving material (p-type doping) or by electrically doping the electron transport layer with an appropriate supply material (n-type doping). The charge carrier density (and thus the conductivity). Furthermore, similar to the experience with inorganic semiconductors, it is foreseeable to be based precisely on certain applications of the p-type and n-type layers used in the element, otherwise it cannot be inferred. Doped charge carrier transport layer (p-type doping of a hole transport layer carried out by a molecular mixture of a receiving type, n-type doping of an electron transport layer carried out by a molecular mixture of a supply type) in organic light emission The use of the diodes is described in documents US 2008/203406 and US 5,093,698.
Electrical doping is also known as redox doping or charge transfer doping. Doping is known to increase the density of charge carriers of a semiconductor substrate towards the charge carrier density of the undoped matrix.
US 2008/227979 discloses in detail the doping of organic transport materials with inorganic dopants and with organic dopants. Basically, efficient electron transport occurs from the dopant to the matrix, which increases the Fermi level of the matrix. For efficient transport in the case of p-type doping, the LUMO energy level of the dopant is preferably more negative than the HOMO energy level of the matrix, or at least slightly more positive than the HOMO energy level of the matrix. (no more than 0.5 eV). For the case of n-type doping, the HOMO energy level of the dopant is preferably more positive than the LUMO energy level of the matrix, or at least slightly more negative than the LUMO energy level of the matrix (not less than 0.5 eV). What is more desirable is that the energy transfer from the dopant to the substrate has an energy level difference of less than +0.3 eV.
A typical example of a doped hole transport material is a copper indigo (CuPc) doped with tetrafluoro-tetracyanium xylene (F4TCNQ) having a HOMO order of about -5.2 eV and a LUMO order of about -5.2. eV; zinc indigo (ZnPc) doped with F4TCNQ (HOMO=-5.2 eV); a-NPD (N,N'-bis(naphthalen-1-yl)-N,N'-di doped with F4TCNQ (phenyl)-benzidine). a-NPD doped with 2,2'-(perfluoronaphthalene-2,6-diphenyl)dipropanecarbonitrile (PD1). a-NPD doped with 2,2',2''-(cyclopropane-1,2,3-extended triyl)tris(2-(p-cyanotetrafluorophenyl)acetonitrile) (PD2). All p-doping in the device example was carried out with 5 mol% of PD2. Other useful hole transport materials are like N4, N4, N4'', N4''-tetrakis ([1,1'-biphenyl]-4-yl)-[1,1':4',1''-Triphenyl]-4,4''-diamine (HT1) is disclosed in WO 2011/134458. Another type of hole transport material is 2,2',7,7'-tetrakis(N,N-di-p-methylphenylamino)-9,9'-cyclohexane (HT2). Another type of hole transport material is N4,N4''-bis(naphthalen-1-yl)-N4,N4''-diphenyl-[1,1':4',1 disclosed in US 2012/223296 ''-Triphenyl]-4,4''-diamine (HT3).
Typical examples of doped electron transport materials are: fullerene C60 doped with acridine orange base (AOB); technetium-3,4,9,10-tetracarboxylic acid-3 doped with white crystal violet , 4,9,10-dianhydride (PTCDA); with four (1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidinium)-di-tungsten (II (W ₂ (hpp) ₄ , ND1) doped 2,9-di(phenanthr-9-yl)-4,7-diphenyl-1,10-morpholine; with 3,6-di-( Dimethylamino)-acridine-doped naphthalenetetracarboxylic acid bis-anhydride (NTCDA); naphthalene tetracarboxylic acid doped with bis(ethylene-dithio)tetrathiafulvalene (BEDT-TTF) -anhydride. For example, 4,4',5,5'-tetracyclohexyl-1,1',2,2',3,3'-hexamethyl-2,2',3,3'-tetrahydro- A useful air-stable precursor of the n-dopant of 1H,1'H-2,2'-diimidazole (ND2) is disclosed in EP 1 837 926. Another material is commercially available 2,4,7,9-1,10-morpholine (ET5).
The organic light-emitting device may include an external light outcoupling layer outside the electrically active region (the region between the electrodes). This external light outcoupling layer is other than the scattering layer. For a top-emitting OLED, the external optical outcoupling can be a layer that matches the refractive index of the stack to enhance optical outcoupling from a transparent top electrode to air. Top-emitting OLEDs are described, for example, in WO 2005/106987, EP 1 739 765. In a preferred embodiment, the scattering layer is in direct contact with the top electrode. The external light outcoupling layer may also contain microspheres on the bottom side of the substrate from which the bottom OLED is illuminated.
The organic light-emitting device may be formed as a non-inverted structure or a reversed structure. In the case of a non-inverted structure, the bottom electrode is the anode and the top electrode is the cathode. In the inverted configuration, the bottom electrode is the cathode and the top electrode is the anode.
The roughened layer can be uniformly formed from a material having a single molecular structure.
The organic light-emitting device can be a large-area illumination device in which the roughened layer is patterned and the pattern can be resolved by the human eye. For example, the pattern has dimensions that can be resolved by the human eye of a human observer viewing the device at a distance of one meter to several meters. This pattern has the advantage of being considered a blurred symbol in the closed state, for example due to the different mirror/diffusion surfaces of the reflective layer. In addition, the symbol can be made to be seen also in the on state, and when the device is set to medium brightness, the human observer can also observe a contrast between the stronger and weaker light outcoupling regions.
The standard value of the human eye resolution is known to be 1 cent (1/60 degree). It is assumed that the viewing distance from the luminescent layer is 1 metre, which corresponds to a resolution of 0.29 mm. If the viewing distance is assumed to be 30 cm, a resolution of 35 is approximately 100 microns. Thus, the value of the lateral distance and/or the width of the linear luminescent layer of approximately 100 microns can be assumed to be a suitable lower limit for the lateral dimension of the luminescent layer that can still be resolved by the human eye.
The process of roughening the layer is adjusted to achieve a preferred growth mode: deposition rate, substrate temperature during deposition, and latency after film deposition (tempering). Low evaporation rates result in small particle densities. On the other hand, if the evaporation rate is too high, the particles will fuse together or the layer may become amorphous. In the procedure for producing the roughened layer, the evaporation rate of the material may range from about 1 to about 10 A/s.
The change between the LUMO of the roughened layer and the LUMO of at least one adjacent layer is greater than 0.5 eV. Preferably, the roughened layer is formed to be undoped. If the material of the roughened organic layer is an HTL (used as an HTL), it is preferred that the amount of change between the HOMO and the HOMO of the adjacent layer is greater than 0.5 eV. Preferably, the roughened layer is formed to be undoped.
The material of the roughened layer may be an insulator based on any practical purpose in the device.
Therefore, the preferred variation has the following layer structure:
- Undoped rough layer / n-type doped ETL / cathode
- Undoped rough layer / p-type doped HTL / anode.
The roughened layer is preferably formed of molecules whose chemical structure is linear and unbranched, and examples are condensed ring systems having less than 7 rings, such as fluorene, phenanthrene, pentabenzene ring, and BPphen. It is also possible to use a chemical structure that allows material to be rotated along at least one axis of the main axis.
In the case where the roughened organic layer also forms an electron transport layer (ETL) (between the cathode and the organic light-emitting layer), it is possible to use materials derived from bridged dioxins (and their higher homogenates), in particular It is 1,4-bis(benzo[d]oxazol-2-yl)benzene.
Among other properties, if used as an electron transporting material or in an electron transporting region/layer, the following materials may be excluded: materials derived from bridged oxazoles (and their higher homogenates), especially 1,4-bis(benzo[d]oxazol-2-yl)benzene.
Among other properties, if used as a hole transport material or in a hole transporting region/layer, the benzoated oxetane can be excluded. In a specific embodiment, the following compounds may be excluded if used as a hole transport material or in a hole transport region/layer between other properties:


Wherein X and Y are different from each other, but are independently selected from the group consisting of oxygen, sulfur, selenium and tellurium; n is 1, 2, 3, 4, 5 or 6; and R _1-9 is independently selected from the group consisting of hydrogen, alkyl and aromatic. a base, a heteroaryl group, a condensed carbocyclic ring, a condensed heterocyclic ring, OR', SR' and NR ₂ ', wherein R' is independently selected from the group consisting of an alkyl group, an aryl group, a heteroaryl group, a condensed carbocyclic ring, and a condensed heterocyclic ring.
The layer below the roughened layer may not include 2,7,9-triphenyl-4-(p-tolyl)pyrido[3,2-h]quinazoline.

1, 50. . . Substrate

2, 51. . . Bottom electrode

3, 5. . . Luminous layer

4, 7. . . Transport layer

6, 22, 32, 41. . . Rough layer

7.1, 13.1, 17.1, 18.1. . . glass substrate

7.2, 13.2. . . ITO

7.3, 13.3. . . HT1: PD2 (97:3) (layer thickness is 30 nm)

7.4, 13.4. . . HT1: PD2 (99:1) (145 nm)

7.5, 13.5. . . HT1 (10 nm)

7.6, 13.6. . . ABHO36. . . NRD129 (99:1) (5 nm)

7.7, 13.7. . . ABHO36: NUBD369 (95:5) (25 nm)

7.8, 13.8. . . ET2 (10 nm)

7.9, 13.9. . . Compound (1d)-(1f)

7.10. . . ET2: ND2 (90:10) (30 nm)

7.11, 13.11. . . Silver (100 nm)

8, 55. . . Top electrode

9. . . Package

10. . . Electrical active area

13.10. . . ET2: ND1 (30 nm)

17.2, 18.2. . . ITO (layer thickness is 90 nm)

17.3, 18.3. . . HT2: PD1 (98.5: 1.5) (50 nm)

17.4, 18.4. . . a-NPD (20 nm)

17.5, 18.5. . . Compound 1d) (10 nm)

17.6, 18.6. . . a-NPD: REO76 (95: 5) (20 nm)

17.7. . . ET5 (10 nm)

17.8. . . ET2 (10 nm)

17.9. . . ET2: ND1 (92: 8) (40 nm)

17.10. . . silver

18.7. . . ET5 (60 nm)

18.8. . . LiQ (2 nm)

18.9. . . Al

21, 31, 40. . . Lower layer

23, 33. . . Granule

twenty four. . . height

25. . . Open space

34. . . Ground plane

42. . . Roughened layer

43. . . Coarse structure

44. . . Outer part

45. . . Inner side

46. . . region

52, 53, 54. . . Organic layer

56. . . Interface

57. . . Roughing department

Al. . . silver

ITO. . . electrode

The invention is explained in more detail below by means of other figures in the drawings. Shown in the schema:
1 is a schematic (cross-sectional) view showing a layered structure of an organic light-emitting device,
Figure 2 is a schematic (cross-sectional) view showing a layered structure having a roughened layer on a lower layer,
Figure 3 is a schematic (cross-sectional) view showing a layered structure having a roughened layer on a lower layer,
Figure 4 is a schematic (cross-sectional view) showing an underlying layer (subsequently deposited with a roughened layer and one of the roughened layers deposited on the roughened layer),
Figure 5 is a schematic (sectional) view showing a layered structure of an organic light-emitting device,
Figure 6 is a profile measurement of a sample layer structure by AFM (Atomic Force Microscopy).
Figure 7 is a diagram showing the layered structure of an organic light-emitting device.
Figure 8 is an experimental result of an organic light-emitting device by SEM (Scanning Electron Microscope),
Figure 9 is an experimental result of an organic light-emitting device by SEM.
Figure 10 is an experimental result of an organic light-emitting device by SEM.
Figure 11 is an experimental result of an organic light-emitting device by SEM.
Figure 12 is an experimental result of an organic light-emitting device by SEM,
Figure 13 is a diagram showing the layered structure of an organic light-emitting device.
Fig. 14 is an experimental result of an organic light-emitting device by SEM, wherein the organic light-emitting device is prepared by the layered structure shown in Fig. 13.
Figure 15 is an experimental result of an organic light-emitting device by SEM, wherein the organic light-emitting device is prepared by the layered structure shown in Figure 13
Figure 16 shows the experimental results of the layered structure by AFM.
Figure 17 is a diagram showing the layered structure of an organic light-emitting device.
Figure 18 is a diagram showing the layered structure of an organic light-emitting device.
Fig. 19 is an experimental result of an organic light-emitting device by SEM.

Fig. 1 is a schematic (sectional) view showing a layered structure of an organic light-emitting device. The organic light emitting device can be provided for an organic light emitting diode (OLED). The layered structure comprises a substrate 1, a bottom electrode 2, an electrical active region 10, a roughened layer 6, and a top electrode 8, the top electrode being covered by a package 9. There is a transport layer 7 between the top electrode 8 and the roughened layer 6. In other embodiments, the transport layer 7 may not be present. The layered structure in the first figure also comprises a light-emitting layer 5 and a transport layer 4. In other embodiments, the transport layer 4 may not be present. In addition, there is another luminescent layer 3 which is made of one or more layers and which may not be present in other embodiments. Unlike the schematic shown in Fig. 1, there may be another transport layer between the light-emitting layer 5 and the roughened layer 6.
Figure 2 is a schematic (cross-sectional) view showing a layered structure having a roughened layer 22 on a lower layer 21. The roughened layer 22 is provided with a non-closed layer. The particles 23 of the roughened layer 22 are separated from one another to provide an island or granular structure. The particles 23 have a height 24 which is located between adjacent particles with an open space or region 25. In the open space 25, the material of the roughened layer 22 does not cover the underlying layer 21. For example, such layer designs are created by the growth of the Volmer-Weber (VW) mode of the roughened layer 22 on the underlying layer 21.
Figure 3 is a schematic (cross-sectional) view showing a layered structure having a roughened layer, wherein the roughened layer 32 is provided on a lower layer 31 with a roughened structure, i.e., particles 33. There is a ground layer 34 made of the same material as the particles 33, which has a thickness of 5 nm or less, and covers the area between the particles 33 of the underlying layer 31 which provide the roughened structure. Together with the ground layer 34, the particles 33 provide an iceberg structure for the roughened layer. For example, such a layer structure is provided by three-dimensional mode growth (Stranski-Krastanow, SK) of the roughened layer 32 on the underlying layer 31.
4 is a schematic (cross-sectional) view showing a lower layer 40, which is followed by a roughened layer 41 and a roughened layer 42 deposited on top of the roughened layer 41. The roughened layer 42 is provided with a roughened portion that includes a roughened structure 43 on the outer portion 44 and the inner portion 45. In other embodiments (not shown), the roughened layer 42 may be provided with a surface roughened portion only on the inner side portion 45, while the outer side portion 44 is flat.
Layer 42 can be doped with one of the transport layers or an electrode as desired.
Figure 4 also depicts a region 46 without a roughened structure (without particles) that can be created, for example, by the use of a hood during evaporation. In region 46, the thickness of layer 42 can be measured directly, such as by a leveling instrument. Note that the drawings are for illustrative purposes only and do not represent their scale.
Fig. 5 is a schematic (sectional) view showing a layered structure representing an organic light-emitting device, having a substrate 50, a bottom electrode 51 (e.g., an ITO anode), and organic layers 52, 53 and 54. The organic-organic interface is indicated by a dashed line (eg 56). The organic layer 54 also contains roughened particles (not explicitly shown) which may result in, for example, the roughened portion 57 of the top electrode 55 of an aluminum cathode.
Figure 6 illustrates a sample of quartz, 30 nm of 2,7,9-triphenyl-4-(p-tolyl)pyrido[3,2-h]quinazoline / 10 nm by AFM. Compound (1a - see below) / 30 nm of 2,7,9-triphenyl-4-(p-tolyl)pyrido[3,2-h]quinazoline / 100 nm silver Profile measurement. The 30 nm 2,7,9-triphenyl-4-(p-tolyl)pyrido[3,2-h]quinazoline layer on quartz is flat with less than 3 nm. Roughness. The layer body of the compound (1a) does not form a closed layer but forms only particles. This measurement is shown from the top of the silver electrode because it freezes the morphology of the layer of compound (1a) (the shortest waiting time).
The organic layered structure contains at least one luminescent layer. A typical layered structure of an organic light-emitting diode is described, for example, in EP 1 705 727, EP 1 804 309. OLEDs can also have a pin layer structure, which is described, for example, in US 7,074,500, US 2006/250076. The n-type dopants and the p-type dopants used in the pin OLEDs are described, for example, in US Pat. No. 6,908,783, US 2008/265,216, WO 07/107306, EP 1 672 714.
The following compounds can be used to create a roughened layer in an organic light-emitting device.





Therefore, the compounds (1a) to (1f) and their synthesis are known. One or more compounds have been used as fluorescent brighteners.
a compound for electron transport layer (4-(dibenzo[c,h]acridin-7-yl)phenyl)diphenylphosphine oxide (ET3) and 7-(4'-(1-phenyl) Synthesis of -1H-benzo[d]imidazol-2-yl)-[1,1'-biphenyl]-4-yl)dibenzo[c,h]acridine (ET4) by the following method get on. THF stands for tetrahydrofuran, MTBE stands for methyl-tert-butyl ether, DCM stands for dichloromethane, Et2O stands for diethyl ether, MeOH stands for methanol, BuLi stands for butyl lithium, HPLC stands for high performance liquid chromatography, NMR stands for nuclear magnetic resonance.
First step: Synthesis of (E)-2-(4-bromobenzoyl)-3,4-dihydronaphthalen-1(2H)-one (c). All operations were carried out in air without any further purification of commercially available solvents/chemicals.



A 250 mL Erlenmeyer flask was filled with tetralone (3.22 g, 22 mmol) and 4-bromobenzaldehyde (5.3 g, 28.6 mmol). This was dissolved in warm tetrahydrofuran (12 mL), and a solution of 4% by weight of KOH in methanol (100 mL) was slowly added to this yellow solution. The reaction was stirred at room temperature for 4 days. The mixture was concentrated and reduced to approximately 10% by volume. The residue was filtered and washed with EtOAc EtOAc EtOAc (EtOAc)
Second step: Synthesis of 7-(4-bromophenyl)-5,6,8,9-tetrahydrodibenzo[c,h]acridine (d). Both reaction steps were carried out under argon.


c (6.54 g, 20.9 mmol) and tetralone (2.93 g, 20.0 mmol) were introduced into a conical flask together with BF ₃ .Et ₂ O (3 mL, 23.7 mmol). The mixture was stirred at 100 ° C for 4 hours and cooled to room temperature. Et ₂ O (25 mL) was added and the mixture was stirred for additional 1 hour. The precipitate was filtered and to Et ₂ O (20 mL) wash. The dried powder (3.8 g) was then introduced into an Erlenmeyer flask together with an ammonia-ethanol solution at 0 °C. The mixture was stirred at room temperature for 5 hours, and the precipitate was filtered and washed with ethanol several times.
2.98 g (34% yield) of a white powder was obtained.
Third step: Synthesis of 7-(4-bromophenyl)dibenzo[c,h]acridine (7). Oxidative dehydrogenation is carried out under argon.


d (2.98 g, 6.80 mmol) was dissolved in 190 mL of dioxane and 2,3-dichloro-5,6-dicyanobenzoquinone (10.9 g, 48 mmol). The mixture was refluxed under argon for 2 days. The reaction mixture was then cooled to room temperature, poured into 600 mL of saturated aqueous sodium carbonate and stirred at 65 ° C for 30 min. The mixture was then cooled to room temperature. The precipitate was filtered and washed with water and dichloromethane.
Yield: 2 g (68%). ¹ H NMR (500 MHz, CD ₂ Cl ₂ ) δ (ppm): 9.80 (d, J = 8.0, 2H), 8.00 - 7.68 (m, 10H), 7.53 (d, J = 9.2, 2H), 7.45 – 7.34 (m, 2H).
Fourth step: Synthesis of (4-(dibenzo[c,h]acridin-7-yl)phenyl)diphenylphosphine oxide (23). The reaction with butyllithium and with diphenylphosphine chloride is carried out in an anhydrous solvent under argon.

(7) (2.84 g, 5.11 mmol) was dissolved in 40 mL THF. The solution was cooled to -78 ° C, and n-BuLi (2.5 mol/L, 3.5 mL, 8.68 mmol) was added dropwise over 20 minutes, and then stirred at this temperature for one hour. Then the temperature was raised to -50 ° C, diphenylphosphonium chloride (1.13 g, 5.11 mmol) was added, and the mixture was stirred overnight at room temperature. The reaction was quenched with MeOH (25 mL) and solvent evaporated. The residue was dissolved in 40 mL of dichloromethane, then 8 mL aqueous H ₂ O ₂ (30% aqueous w/w) was added and stirred overnight. The reaction mixture was then washed several times with 50 mL of brine, then the organic phase was dried and evaporated. The crude product was purified via column chromatography (SiO _2, dichloromethane, and then DCM / MeOH 97: 3) was purified. The foamy product obtained by evaporation in vacuo was then washed with 200 mL of MTBE.
The yield was 1.6 g (43%). HPLC purity >97%. .
NMR: ³¹ P NMR (CDCl ₃ , 121.5 MHz): δ (ppm): 29 (m). ¹ H NMR (500 MHz, CD ₂ Cl ₂ ) δ (ppm): 9.79 (d, 8.06 Hz, 2H), 7.86 (m, 10 Hz), 7.75 (m, 2 Hz), 7.69 (d, 9.20 Hz, 2H), 7.58 (m, 8 Hz), 7.44 (d, 9.18 Hz, 2H).
Fifth step: 7-(4'-(1-phenyl-1H-benzo[d]imidazol-2-yl)-[1,1'-biphenyl]-4-yl)dibenzo[c , h] Synthesis of acridine (26). The Pd-catalyzed condensation reaction is carried out under argon.


(7) (2.1 g, 4.8 mmol), 1-phenyl-2-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) Phenyl)-1H-benzo[d]imidazole (3.8 g, 9.6 mmol), tetrakis(triphenylphosphine)palladium (830 mg) and 17 mL of 1 M aqueous potassium carbonate solution were introduced with 35 mL of degassed toluene. Erlenmeyer flask. The reaction was stirred at 80 ° C for 36 hours, cooled to room temperature and filtered. The resulting solid was then dissolved in 600 mL DCM and filtered on a pad of celite. The volatiles were removed by rotary distillation and the solid residue was dried in a vacuum oven overnight.
The yield is 1.2 g (40%). HPLC purity > 98%. ¹ H NMR (500 MHz, CD 2 Cl 2 ) δ (ppm): 9.82 (d, 8.16 Hz, 2H), 7.85 (d, 7.60 Hz, 2H), 7.88 (m, 5H), 7.79 (m, 2H), 7.76 ( s, 4H), 7.74 (s, 1H), 7,63 (d, 9.2 Hz, 2H), 7.59 (m, 3H), 7.56 (m, 1H), 7,43 (dd, 3.13 Hz, 5.32 Hz, 2H), 7.36 (m, 1H), 7.29 (dt, 3.01 Hz, 3.01 Hz, 7.35 Hz, 2H).
Compound 2,7,9-triphenyl-4-(p-tolyl)pyrido[3,2-h]quinazoline (ET1) and 4-(naphthalen-1-yl)-2,7,9 The synthesis of triphenylpyrido[3,2-h]quinazoline (ET2) is described in document EP 1 970 371.
The following sequence of layers is only an example of how to produce the desired form. The layer sequence is contained in an organic light emitting diode. In each layer pair, a layer system made of the first material is used as the under layer (ETL or n-ETL), and a subsequent layer system made of a second material is used as the rough layer. The structure in the device stack is as follows: EML / under layer / rough layer.
The best results are achieved by inserting an electrically doped layer into a layer sequence in an OLED stack. All deposition is done at room temperature. The materials used in the luminescent layer (sold by Sun Chemicals) are indicated by their transaction codes ABH036, NRD129 and NUB369.

In contrast to most of the techniques used to enhance optical outcoupling, in which different means of adding do not provide an additive effect on the performance of the OLED, it has been surprisingly found in the present invention that OLEDs can be further significantly enhanced.
By adding an external light outcoupling foil comprising an array of microlenses to enhance light extraction, the efficiency of almost optimal OLEDs is almost doubled to a factor of 2, resulting in power efficiencies higher than 60 lm/W.
The organic light-emitting device was prepared as shown in Fig. 7. Prepare the following layered structure:
7.1: Glass substrate
7.2: ITO
7.3: HT1: PD2 (97: 3) (layer thickness is 30 nm)
7.4: HT1: PD2 (99:1) (145 nm)
7.5: HT1 (10 nm)
7.6: ABH036: NRD129 (99: 1) (5 nm)
7.7: ABH036: NUBD369 (95: 5) (25 nm)
7.8: ET2 (10 nm)
7.9: Compound (1d)-(1f)
7.10: ET2: ND2 (90: 10) (30 nm)
7.11: Silver (100 nm)
As a control group, an organic light-emitting device containing no layer 7.9 was prepared.
Regarding the apparatus comprising layer 7.9, the following materials were used: compound (1d), compound (1e), and compound (1f).
Reference is made to Figs. 8 to 12 below.
An organic light-emitting device prepared by a layered structure as shown in Fig. 7 was prepared and studied. Fig. 8 to Fig. 12 show experimental results obtained by SEM (Scanning Electron Microscope), and sections of different devices were prepared by focusing ion beam (FIB).
In Figures 8 through 12, the top view shows a cross-section of the device, while the lower view shows a top view of the top electrode of the device. For cross-sectional images, the following parameters were used: magnification of 100,000 x, EHT (electron high tension) of 1 kV, working distance (WD) of 5.1-5.2 mm, aperture size of 30 μm, and detector inside the lens barrel (in -lens) Detector or SESI (in combination with secondary electron secondary ions) (only in Figure 12a). Regarding the upper view of the electrode surface, the following parameters were used: magnification of 50,000x, EHT (electron high tension) of 3kV, working distance (WD) of 4.9-5.1 mm, pore size of 30 μm, and detector SESI or SE2 (only in Figure 15b).
Regarding Fig. 8, layer 7.9 is prepared from material (A) having a layer thickness of 6.7 nm (deposition rate of 3 A/s). Regarding Figure 9, layer 7.9 was prepared from material (B) having a layer thickness of 6.1 nm (deposition rate of 3 A/s). Regarding Fig. 10, layer 7.9 is prepared from material (A) having a nominal layer thickness of 10.1 nm (deposition rate is 1 A/s). With regard to Figure 11, layer 7.9 is prepared from material (B) having a nominal layer thickness of 10.1 nm (deposition rate of 1 A/s). Regarding Fig. 12, layer 7.9 was prepared from material (C) having a layer thickness of 5.6 nm (deposition rate of 3 A/s).
The experimental results of the devices shown in Figs. 8 to 12 are summarized below.


The area is the active area of the OLED. CIE X and CIE Y are the chromaticity coordinate systems defined by the International Lighting Association (CIE) in 1931. Peff refers to power efficiency (or lighting efficiency) in lm/W. EQE is the external quantum efficiency. The EQE is promoted to the ratio between the EQE of the stack having the roughened layer and the EQE of the stack without the roughened layer. These values are measured in an integrated sphere from the current indicated in the table.
Another organic light-emitting device was prepared as shown in Fig. 13. Prepare the following layered structure:
13.1: Glass substrate
13.2: ITO
13.3: HT1: PD2 (97:3) (layer thickness is 30 nm)
13.4: HT1: PD2 (99:1) (145 nm)
13.5: HT1 (10 nm)
13.6: ABH036: NRD129 (99: 1) (5 nm)
13.7: ABH036: NUBD 369 (95: 5) (25 nm)
13.8: ET2 (10 nm)
13.9: Compound (1d)-(1f)
13.10: ET2: ND1 (30 nm)
13.11: Silver (100 nm)
As a control group, an organic light-emitting device containing no layer 13.9 was prepared.
Fig. 14 and Fig. 15 show the results of SEM experiments of the organic light-emitting device prepared by the layered structure shown in Fig. 13. Similarly, the upper graphs in Figures 14 and 15 show the cross-section, while the lower graph shows the top view of the individual devices.
With regard to Figures 14 and 15, layer 13.9 was prepared from compound (1a). The deposition rate of 0.8 A/s was used in Figure 14, while the sample in Figure 15 had a deposition rate of 6 A/s. It should be noted that the active areas are different, and therefore, the efficiency improvement in these two cases cannot be compared due to the influence of the thickness of the substrate. There are also some differences in the stack that do not affect morphology and efficiency improvement: Figure 14 - ET2: ND1 (15%), 100 nm cathode, and Figure 15 - ET2: ND1 (8%), 250 nm The cathode.
The experimental results of the devices shown in Figs. 14 and 15 are summarized below.


Figures 16a to 16d show the results of the AFM experiment of the layered structure in which the compound (1a) was deposited on the organic layer made of ET2.
Figures 16a and 16c show the results of a layered structure without a metal top electrode and a metal top electrode (made of a 100 nm silver layer). Figures 16b and 16d show the results of depositing a layered structure of a transport layer (made of 30 nm thick ET2) on the roughened layer. Similarly, Figures 16b and 16d show the results with and without a metal top electrode made of silver.
An organic light-emitting device was prepared as shown in Fig. 17. Prepare the following layered structure:
17.1: Glass substrate
17.2: ITO (layer thickness is 90 nm)
17.3: HT2: PD1 (98.5: 1.5) (50 nm)
17.4: a-NPD (20 nm)
17.5: Compound 1d) (10 nm)
17.6: a-NPD: RE076 (95: 5) (20 nm)
17.7: ET5 (10 nm)
17.8: ET2 (10 nm)
17.9: ET2: ND1 (92: 8) (40 nm)
17.10: The material of the silver electron blocking layer (EBL) 17.4 may alternatively be HT1, HT2 and HT3. The scattering layer 17.5 can also be made of a material called compounds 1e) and 1f). In an alternate embodiment, the device can be fabricated without the scattering layer 17.5. The abbreviation RE076 refers to the commercially available material 铱(III) bis(2-methyldibenzo-[f,h]quinoxaline) (acetylacetonate).
Another organic light-emitting device was prepared as shown in Fig. 18. The self-crystallized compound 1d) is disposed on the side of the cavity of the stack. This is an example of a stack in which the roughening layer is not allowed to be disposed on the electron transport side. Prepare the following layered structure (pii-stack):
18.1: Glass substrate
18.2: ITO (layer thickness is 90 nm)
18.3: HT2: PD1 (98.5: 1.5) (50 nm)
18.4: a-NPD (20 nm)
18.5: Compound 1d) (10 nm)
18.6: a-NPD: RE076 (95: 5) (20 nm)
18.7: ET5 (60 nm)
18.8: LiQ (2 nm)
18.9: Al
The material of the electron blocking layer (EBL) 18.4 may alternatively be HT1, HT2 and HT3. The scattering layer 18.5 can also be made of materials known as compounds 1e) and 1f).
The table below shows the external quantum efficiency (EQE) of different EBL materials with and without compounds 1d) to 1f). The external quantum efficiency is measured in an integrated sphere at a fixed current density (3 mA/cm2). Increased efficiency
35% to 40%.

Figure 19 shows a cross section of an organic light-emitting device having a layer (3 nm) of one of the compounds 1d) to 1f), wherein the layer is disposed adjacent to the HT1. HT1 acts as an electron blocking layer (EBL). The interface between the last organic layer and the cathode is corrugated. Images were acquired using SEM. From Fig. 19, it can be concluded that the optical outcoupling mechanism is the same as when the layer of one of the compounds 1d) to 1f) is provided on the electron transport side of the device.
The inventive features disclosed in the foregoing description, the scope of the claims, and the drawings are of particular importance in the individual and any combination of the embodiments of the invention.

1. . . Substrate

2. . . Bottom electrode

3, 5. . . Luminous layer

4, 7. . . Transport layer

6. . . Rough layer

8. . . Top electrode

9. . . Package

10. . . Electrical active area

Claims (13)

An organic light-emitting device in a layered structure, comprising:
- a substrate,
- a bottom electrode,
a top electrode, wherein the bottom electrode is closer to the substrate than the top electrode
An electrically active region comprising one or more organic layers and being provided between and in electrical contact with the bottom electrode and the top electrode,
a illuminating area, which is provided in the electrically active area, and
a roughened layer, the roughened layer being provided as a non-closed layer in the electrically active region, and by roughening the top electrode facing at least one inner side of the electrically active region, and the top electrode is not At least one of an outer side of the electrically active region and an electrode refining portion is provided to the top electrode. The organic light-emitting device of claim 1, wherein the rough layer comprises an organic material. The organic light-emitting device of claim 1 or 2, wherein the rough layer is provided by a plurality of dispersed particles randomly distributed above a lower layer, the rough layer being deposited on the lower layer on. An organic light-emitting device according to at least one of the preceding claims, wherein the top electrode is provided on a top layer of one of the electrical active regions, the top layer of the electrical active region being provided by the top layer The roughened layer below is roughened. An organic light-emitting device according to at least one of the preceding claims, wherein the roughened layer is disposed between the light-emitting region and the top electrode. The organic light-emitting device of claim 1, wherein the roughening layer is provided between the light-emitting region and the bottom electrode. An organic light-emitting device according to at least one of the preceding claims, wherein the roughened layer is provided having from about 3 nm to about 50 nm, preferably from about 3 nm to about 15 One of the nominal thickness of the nanometer. An organic light-emitting device according to at least one of the preceding claims, wherein the roughened layer is provided on or covered by an electrically doped charge carrier transport layer, or sandwiched between two electrical properties. Doped between the charge carrier transport layers. An organic light-emitting device according to at least one of the preceding claims, wherein the roughened layer is provided between an electron transport layer and a cathode, or between a hole transport layer and an anode, and direct contact. An organic light-emitting device in a layered structure, comprising:
- a substrate,
- a bottom electrode,
a top electrode, wherein the bottom electrode is closer to the substrate than the top electrode
An electrically active region comprising one or more organic layers and being provided between and in electrical contact with the bottom electrode and the top electrode,
a illuminating area, which is provided in the electrically active area, and
a roughened layer, which is provided between the substrate and the bottom electrode as a non-closed electrically inactive layer, and at least one electrode is provided to the bottom electrode by roughening the bottom electrode Ministry of Chemicals. A method of producing an organic light-emitting device that is provided with a layered structure, the method comprising the steps of:
- providing a substrate,
Depositing a bottom electrode on the substrate,
Forming an electrically active structure, the forming step comprising the steps of:
Depositing a second organic semiconducting layer on the roughened layer, and depositing a first organic semiconducting layer on the bottom electrode,
Depositing a rough layer on the organic semiconducting layer, and
- depositing a top electrode over the electrically active structure. The method of claim 11, wherein the roughened layer is deposited by vacuum thermal evaporation, and a nominal thickness of the roughened layer is controlled by a quartz crystal monitor during vacuum deposition. . The method of claim 11 or 12, further comprising the steps of: depositing the rough layer directly on the first organic semiconductor layer, and selecting a material of the first organic semiconductor layer and The material of the rough layer is used to facilitate the Volmer-Weber growth model.