Organic light-emitting device and method for manufacturing an organic light-emitting device

Abstract

Organic light-emitting component (100), comprising - a flexible substrate (11) with a first main surface (111) comprising a metal foil, - an inorganic electrically insulating base layer (12) on the first main surface (111), - in an active area (20) a first electrode (14), an organic functional layer stack (15) and a transparent second electrode (16) on the base layer (12) and - a transparent encapsulation (19) over the active area (20) and a marginal area (21) surrounding the active area (20) in a lateral direction, wherein - the first electrode (14) is divided into at least two mechanically and electrically separated functional areas (141) and - the second electrode (16) is arranged continuously over the at least two functional areas (141), wherein - the organic functional layer stack (15) is applied continuously over the functional areas (141) of the first electrode (14), - the functional areas (141) are separated from each other by a lateral spacing, and - the first electrode (14) tapers off flat, with an aspect ratio of edge width (31) to edge height (32) greater than or equal to 2.

Description

[0001] An organic light-emitting component and a method for manufacturing an organic light-emitting component are described.

[0002] Organic light-emitting diodes (OLEDs) can be advantageous light sources for a wide variety of applications, with each OLED having to meet different requirements depending on the application. For example, in the automotive sector, it may be desirable for an OLED to be both bendable and segmented into multiple light-emitting zones. At the same time, however, sufficient robustness must be ensured to meet the extreme demands of automotive applications, as is currently only known from OLEDs with rigid glass substrates. OLEDs on ultrathin glass substrates, on the other hand, cannot meet the bending radii requirements of the automotive sector.

[0003] Furthermore, it is advantageous if the inactive area of ​​an OLED, also known as the dead zone, which represents the proportion of the surface that does not emit light during operation, is as small as possible. For example, the border around the light-emitting area or the distance between light-emitting segments should not be too large. On the other hand, the border around the organic layers and electrodes, in particular, should be large enough to prevent delamination of the encapsulation.

[0004] The publication DE 10 2014 112 171 A1 describes a method for detecting a short circuit in a first light-emitting diode element and an optoelectronic assembly.

[0005] The publication DE 10 2015 102 447 A1 describes an organic light-emitting diode.

[0006] The publication DE 10 2013 110 449 A1 describes a component and a method for manufacturing a component.

[0007] The publication DE 10 2015 103 702 A1 describes a method for manufacturing an optoelectronic component.

[0008] At least one objective of certain embodiments is to specify an organic light-emitting component. At least one objective of further embodiments is to specify a method for manufacturing such a component.

[0009] These problems are solved by an object and a method according to the independent claims. Advantageous embodiments and further developments of the object are characterized in the dependent claims and are further described in the following description and drawings.

[0010] An organic light-emitting device has a substrate with a first main surface. The first main surface can, in particular, be the surface on which the further layers of the device, especially electrodes and organic layers, are deposited.

[0011] The substrate has a second main surface opposite the first, which can be an outer surface of the component. The main surfaces are preferably parallel to each other. In particular, the substrate can be film-shaped, with the two main surfaces having significantly larger dimensions compared to the distance between the first and second main surfaces. This distance can also be referred to as the thickness of the substrate. A direction along the first main surface is referred to here and in the following as the lateral direction. In the case of a flat first main surface, "lateral" can thus mean parallel to the first main surface. In the case of a curved main surface, "lateral" can mean a direction following the curvature. A direction perpendicular to the first main surface is referred to here and in the following as the vertical direction.

[0012] According to a further embodiment, the substrate is flexible. This means that the substrate can be bent, folded, and / or rolled to a minimal bending radius without damaging or destroying its functionality. The same applies, in particular, to the organic light-emitting component as a whole. For this purpose, the substrate can be made of a material that is flexible at a sufficiently small thickness. Preferably, the substrate can be a metal foil or be made of a metal foil. The substrate can also be made of or consist of one or more metals, selected, for example, from one or more of a group consisting of Fe, Cr, Ag, Al, Cu, Sn, Zn, Mg, Ni, as well as alloys and mixtures thereof.

[0013] For example, the substrate can be a foil made of or consisting of steel and / or aluminum or an aluminum alloy and / or copper and / or nickel. The thickness of the substrate can be, in particular, less than or equal to 150 µm, less than or equal to 100 µm, less than or equal to 60 µm, or even less than or equal to 40 µm. Furthermore, the thickness of the substrate can be greater than or equal to 10 µm or greater than or equal to 30 µm. These thickness values ​​apply specifically to a metal foil. An additional foil, for example, a polymer foil, can be applied to one or both sides of the metal foil.

[0014] The organic light-emitting device described here offers advantages over other flexible OLEDs due to its use of a substrate with or made from a metal foil. Flexible OLEDs can also utilize flexible substrates based on plastic films or ultrathin glass. However, since plastic films are not hermetically sealed, a complex and error-prone substrate-side encapsulation is necessary to protect the organic layers from moisture and gas diffusion, particularly in the vertical direction through the substrate. Ultrathin glass typically does not meet the usual requirements regarding the minimum bending radius and is prone to processing defects. A metal foil-based substrate, on the other hand, can be hermetically sealed against moisture and harmful gases and usually allows for smaller bending radii than ultrathin glass.

[0015] A base layer is applied to the first main surface of the substrate. Preferably, the base layer can be applied directly to a metal foil forming the substrate. The base layer can be applied, for example, to flatten and / or electrically insulate the first main surface of the substrate. In the latter case, the base layer can be electrically insulating. Preferably, the base layer can cover the entire first main surface of the substrate. Furthermore, it is also possible for the base layer to be applied additionally to the second main surface or around the perimeter, i.e., also to the side surfaces.

[0016] According to a further embodiment, the base layer comprises or is formed by an inorganic material. The inorganic material can be applied, in particular, by means of a deposition process, preferably by means of a chemical vapor deposition process and / or an atomic layer deposition process. Furthermore, the following processes are also possible: enameling, sol-gel process, sintering, physical vapor deposition (PVD), anodizing, in particular a chemical conversion of the surface of the substrate comprising a metal foil to an oxide, plasma coating, and thermal spraying. The inorganic material can also be electrically insulating, so that in this case the base layer can be inorganic and, as described above, electrically insulating.The inorganic material can be selected from one or more oxides, nitrides and oxynitrides, or carbides, for example, with one or more materials selected from Si, Al, Zn, Zr, Ti, Hf, La, and Ta. For example, the inorganic material can include or consist of silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, aluminum nitride, zinc oxide, zirconium oxide, titanium oxide, hafnium oxide, lanthanum oxide, and / or tantalum oxide. The base layer can also consist of a sequence of multiple layers, each containing one or more of the aforementioned materials. The thickness of the base layer can be, for example, greater than or equal to 10 nm, greater than or equal to 50 nm, greater than or equal to 100 nm, greater than or equal to 200 nm, greater than or equal to 500 nm, or greater than or equal to 1 µm. Furthermore, the thickness of the base layer can be less than or equal to 10 µm, less than or equal to 5 µm, or less than or equal to 1 µm.Furthermore, in addition to the base layer, a planarization layer can be applied on or beneath it, for example, made of or containing a polymer, which can further flatten the substrate. This planarization layer can be applied over a large area and be unstructured, or it can be structured, for example, only in the active region described below.

[0017] According to another embodiment, the substrate is hermetically sealed. This means that over the typical lifetime of the organic light-emitting device, which can be several years in the automotive sector, for example, no significant ingress of moisture or harmful gases such as oxygen or hydrogen sulfide occurs through the substrate, which could damage the organic materials of the organic light-emitting device. The seal of the substrate can be achieved, for example, by a suitable metal foil, a suitable base layer, or a combination thereof.

[0018] According to a further embodiment, a first electrode, an organic functional layer stack, and a transparent second electrode are applied to the substrate on the first main surface. In particular, the electrodes and the organic functional layer stack can be arranged on the base layer. The fact that a first layer is applied "on" or "over" a second layer can, here and in the following, particularly mean that the first and second layers are arranged vertically one above the other and that the first layer is further away from the substrate than the second layer, i.e., that the second layer is arranged between the substrate and the first layer.

[0019] In particular, the first electrode can be arranged between the substrate and the organic functional layer stack, and further between the base layer and the organic functional layer stack, while the organic functional layer stack is arranged between the first electrode and the transparent second electrode. The organic functional layer stack can include at least one organic light-emitting layer, which is designed and configured to generate light during operation of the organic light-emitting device.The light can be emitted at least through the transparent electrode, so that on the side of the second electrode facing away from the organic functional layer stack, there is a light-emitting surface of the organic light-emitting device, through which light generated in the organic functional layer stack during operation is emitted. In particular, the organic light-emitting device can be configured as an organic light-emitting diode (OLED) that, during operation, can emit visible light in a direction away from the substrate as seen from the organic functional layer stack. On the substrate side, the organic light-emitting device can be non-transparent, in particular, for example, due to a non-transparent substrate and / or a non-transparent base layer and / or a non-transparent first electrode.

[0020] In this and the following, "transparent" refers to a layer that is permeable to at least visible light. The transparent layer can be clearly translucent or at least partially light-scattering and / or partially light-absorbing, so that a layer described as transparent can, for example, also be diffusely or milkily translucent. Preferably, a layer described here as transparent is designed to be as permeable to visible light as possible, such that the absorption of light generated in the organic light-emitting component is minimized. "Non-transparent" accordingly means opaque to light, especially to the light generated in the organic light-emitting component.

[0021] The organic light-emitting device has an active region and a peripheral region surrounding the active region laterally. In other words, when viewed vertically, the active region is enclosed by the peripheral region. The first electrode, the second electrode, and the organic functional layer stack are deposited on the substrate in the active region, while the peripheral region is specifically free of the organic functional layer stack. This means that the organic light-emitting device can generate light in the active region via the first and second electrodes and the organic functional layer stack during operation. This light can be emitted directly through the light-emitting surface in the active region. The peripheral region, however, may appear non-luminous during operation of the organic light-emitting device.Such a region can also be referred to as a "dead zone". Preferably, the distance between the edge of the first main surface of the substrate and the active region or individual elements of the device, such as the metallization and insulating layers described below or the organic functional layer stack, can be less than or equal to 4 mm, less than or equal to 3 mm, or less than or equal to 2 mm. Furthermore, the distance can preferably be greater than or equal to 100 µm, greater than or equal to 200 µm, greater than or equal to 500 µm, or greater than or equal to 1 mm.

[0022] The first electrode is divided into at least two mechanically and electrically separated functional areas. In other words, the first electrode has two independently electrically contactable areas arranged laterally adjacent to each other. This allows for the formation of separately operable luminescent segments of the organic light-emitting component, thus segmenting the organic light-emitting component. The functional areas can be separated from each other, for example, by an insulating layer and / or by a lateral spacing. Particularly preferably, the functional areas can have a lateral distance of less than or equal to 100 µm, less than or equal to 50 µm, less than or equal to 25 µm, or greater than 0 µm.The resulting gap between the functional areas can be filled with the insulating layer or with material from the organic functional layer stack.

[0023] The second electrode is arranged continuously over at least two functional areas of the first electrode. Furthermore, the organic functional layer stack is also applied continuously over the functional areas of the first electrode. The segmentation of the organic light-emitting device can therefore be achieved solely by segmenting the first electrode into at least two functional areas. This ensures that the application of the organic functional layer stack and the second electrode does not limit the minimum distance between the light-emitting segments of the device. It is also possible for the second electrode and / or the organic functional layer stack to be segmented, with the segments of the second electrode and / or the organic functional layer stack differing from each other and / or from the functional areas of the first electrode.

[0024] According to a further embodiment, an encapsulation is applied over the first and second electrodes and the organic functional layer stack, covering the active region and at least partially the edge region. In other words, the encapsulation projects laterally beyond the active region, so that it can encapsulate the organic functional layer stack from the side, i.e., from a lateral direction. The encapsulation can particularly preferably be formed by a so-called thin-film encapsulation, which comprises at least one or more thin layers deposited onto the electrodes and the organic functional layer stack by means of a deposition process, preferably by means of a chemical vapor deposition process and / or an atomic layer deposition process.The encapsulation is designed to be particularly transparent, allowing the light generated during operation within the organic functional layer stack to be emitted outwards through the transparent second electrode and the encapsulation. The encapsulation can form an outer layer of the device facing away from the substrate, thus creating a light-emitting surface. Furthermore, it is possible to apply a protective layer to the encapsulation, for example, made of a transparent plastic such as acrylic, for mechanical scratch protection, and / or to incorporate another barrier film and / or optical structures to enhance light emission.

[0025] The encapsulation can preferably cover the substrate on the first main surface, except for one or more electrical connection areas through which the organic light-emitting device can be electrically contacted from the outside. The electrical connection area(s) can be electrode terminals and suitable for connecting the first and second electrodes to an external current and / or voltage supply. The encapsulation can extend to one, more, or all edges of the first main surface. In particular, the encapsulation is limited to the first main surface. In other words, the encapsulation is applied only to the first main surface and does not extend beyond it.This enables the fabrication of the organic light-emitting device (OLD) in a film composite containing multiple OLDs, whose layers are applied to a large-area substrate film. The individual components can be obtained by dividing the composite. Furthermore, the encapsulation does not necessarily have to extend to the edge of the main surface. If at least a portion of the edge is free of encapsulation, the base layer can protrude laterally beneath the encapsulation. It is also possible for the encapsulation to be applied, at least partially, directly to the base layer at the edge. Since both the base layer and the encapsulation can be made of an inorganic material such as an oxide, nitride, or oxynitride, very good adhesion of the encapsulation to the base layer can be achieved.Furthermore, the base layer and the encapsulation can be made of the same or similar material, resulting in identical or similar coefficients of thermal expansion for both layers, which can further promote reliable adhesion. Additionally, the encapsulation can extend beyond the primary surface and cover one, several, or all of the substrate's faces. This is particularly feasible when the encapsulation is applied to a single, non-integrated component.

[0026] According to a further embodiment, a metallization layer is applied in contact with the first electrode layer. The metallization layer can be arranged in direct contact with the first electrode, particularly on, beside, or beneath it. The fact that the metallization layer is in direct contact with the first electrode means, in particular, that a portion of the metallization layer is in contact with the first electrode. Another portion of the metallization layer may also not be in contact with the first electrode. Such a portion may, for example, be in direct contact with the second electrode. For instance, the metallization layer can be arranged between the base layer and the first electrode. In this case, the metallization layer can also be arranged beneath the entire first electrode.Furthermore, the metallization layer can be located on the first electrode at the edge of the substrate. It is also possible for the metallization layer to be arranged laterally next to the first electrode. In particular, it is also possible for the metallization layer to be located exclusively at the edge. The metallization layer can protrude laterally beneath the encapsulation. Furthermore, the encapsulation can be located, at least partially, directly on the metallization layer at the edge. The metallization layer and the first electrode can be different, the same, or partially the same.

[0027] According to a further embodiment, at least a portion of the metallization layer forms an electrode connection or a plurality of electrode connections for the electrical connection of the organic light-emitting device to an external power supply. Here, for example, separate portions of the metallization layer can each form at least one electrode connection in contact with each of the functional areas of the first electrode and with the second electrode. In other words, the metallization layer can have at least three separate areas by means of which the at least two functional areas of the first electrode and the second electrode can be electrically contacted. Separate areas of the metallization layer can be separated from each other like the functional areas of the first electrode and / or have distances from each other like the functional areas of the first electrode.

[0028] For a process for manufacturing the organic light-emitting device, one or more methods can be used for the fine structuring and precise positioning of the metallization layer, and in particular its separate areas, the first electrode, and in particular its functional areas, as well as optionally an insulating layer, for example for the electrical isolation of functional areas. These methods can be selected from photolithography, printing techniques, laser techniques, or combinations thereof. Using these methods, it can be ensured that the base layer on the substrate remains undamaged and that no vapor deposition masks with mechanical alignment are required for the fine structuring of the aforementioned layers.This allows for very small spacings and advantageous dimensions of the layers and functional areas, which have not been achieved at these sizes in previously known flexible OLEDs. The characteristics described above and below apply equally to the organic light-emitting device and to the process for manufacturing the organic light-emitting device.

[0029] In particular, the combination of a hermetically sealed substrate with a metal foil and an inorganic, electrically insulating base layer, as well as a thin-film encapsulation, can enable automotive-grade robustness of the component. The finely structured and precisely positioned metallization layer, first electrode, and insulating layer allow for fine segment boundaries and defined dead zones of preferred dimensions.

[0030] Further advantages, advantageous embodiments and further developments result from the exemplary embodiments described below in conjunction with the figures.

[0031] They show: Fig. 1 a schematic representation of an organic light-emitting component according to an exemplary embodiment, Fig. 2 and Fig. 3 schematic representations of organic light-emitting components according to further embodiments, Fig. 4A to 4C schematic representations of details of organic light-emitting components according to further embodiments and Fig. 5 a schematic representation of an organic light-emitting component according to a further embodiment

[0032] In the exemplary embodiments and figures, identical, similar, or similarly functioning elements may be designated with the same reference numerals. The depicted elements and their relative sizes are not to be considered to scale; rather, individual elements, such as layers, components, building elements, and areas, may be exaggerated for clarity and / or better understanding.

[0033] In Fig. Figure 1 shows a schematic sectional view of an embodiment of an organic light-emitting device 100. The device 100 is specifically designed as an organic light-emitting diode (OLED).

[0034] The organic light-emitting device 100 comprises a substrate 11 on which an organic functional layer stack 15 is arranged on a first main surface 111 between a first and second electrode 14 and 16. The organic functional layer stack 15 comprises at least one organic light-emitting layer, enabling the device 100 to generate and emit light during operation. The second electrode 16 is transparent, allowing light generated in the organic functional layer stack 15 during operation to be emitted by the organic functional layer stack 15 through the transparent second electrode 16. On the side facing away from the first main surface 111, the substrate 11 has a second main surface 112, which forms an outer surface of the organic light-emitting device 100.The region of the organic light-emitting device 100, in which the organic functional layer stack 15 is formed and in which light can thus be generated during operation, forms an active region 20 of the device 100. The active region 20 is surrounded laterally by a boundary region 21, which is free of the organic functional layer stack 15.

[0035] The substrate 11 is flexible and can be bent, folded, and / or rolled to a minimal bending radius without any damage or destruction to its functionality. The flexible substrate 11 also allows the organic light-emitting component 100 to be flexible. In the illustrated embodiment, the substrate 11 is formed by a metal foil. Alternatively, the substrate 11 can also consist of a metal foil, for example, a foil composite with a metal foil onto which a polymer film is laminated on one or both sides. The substrate 11 can, in particular, be made of a foil of or consisting of steel and / or aluminum or an aluminum alloy and / or copper and / or nickel, and can have a thickness of greater than or equal to 10 µm and less than or equal to 150 µm, or less than or equal to 100 µm, or less than or equal to 60 µm, or even less than or equal to 40 µm.Other materials, as described above in the general section, are also possible. Substrate 11 is particularly hermetically sealed, thus providing protection against moisture and harmful gases that could, for example, damage the organic functional layer stack 15. Substrate 11 therefore allows for good flexibility combined with sufficient density.

[0036] To produce the organic light-emitting device 100, a film substrate can be provided that represents a composite of a large number of substrates 11 that have not yet been separated. A plurality of organic light-emitting devices 100 can be defined laterally adjacent to each other on the film substrate by applying the layers described below. The composite can then be separated into a plurality of organic light-emitting devices 100 by subsequent cutting. Such fabrication in a film composite can also mean that the layers described below are applied exclusively to the first main surface 111 and do not extend beyond the first main surface 111, for example, to a side surface or to the second main surface 112 of the substrate 11.As an alternative to manufacturing in a composite process, the component 100 can also be manufactured by applying the layers described below to a substrate 11 that is already provided in its final size.

[0037] A base layer 12 is applied to the first main surface 111 of the substrate 11 and below the electrodes 14, 16 and the organic functional layer stack 15. In particular, the base layer 12 can cover the entire first main surface 111 of the substrate 11. Preferably, the base layer 12 can be applied directly to the substrate 11 and serve, for example, to planarize and / or electrically insulate the first main surface 111 of the substrate 11. For this purpose, the base layer 12, which is particularly preferably an inorganic layer and accordingly comprises an inorganic material, is designed to be electrically insulating.The base layer 12 can be applied, in particular by means of a deposition process, preferably by means of a chemical vapor deposition process and / or an atomic layer deposition process, and can comprise one or more of the materials described above in the general section, for example silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, aluminum nitride, zinc oxide, zirconium oxide, titanium oxide, hafnium oxide, lanthanum oxide, and / or tantalum oxide. The base layer 12 can also comprise or consist of a sequence of multiple layers. The thickness of the base layer can, for example, be greater than or equal to 10 nm and less than or equal to 10 µm. All further layers of the component are subsequently applied to the base layer 12. Furthermore, it is also possible for the base layer 12 to be additionally applied to the second main surface 112 or circumferentially, i.e., additionally to the side surfaces of the substrate 11.Furthermore, a planarization layer, for example made of or containing a polymer, can be applied on or beneath the base layer 12. The planarization layer can be structured and, for example, applied only in the active area 20. The base layer 12 can be hermetically sealed, particularly in the lateral direction, i.e., along the first main surface 111, thus preventing lateral diffusion of harmful gases and moisture.

[0038] The first electrode 14 can, for example, comprise or be composed of a metal or a transparent conductive oxide (TCO), or a layer combination of these materials. The first electrode 14 need not be transparent; it can also be non-transparent and preferably reflective. The second electrode 16 can comprise or be composed of a TCO or a transparent metal, i.e., a metal or metal alloy with a sufficiently small thickness in the range of a few tens of nanometers or less, or a layer combination of these materials. Furthermore, the second electrode 16 can also comprise metallic network structures or conductive networks, for example, with or made of silver, and / or graphene or carbon-containing layers, or a combination of the aforementioned transparent materials.TCOs are transparent, conductive materials, typically metal oxides such as zinc oxide, tin oxide, aluminum tin oxide, cadmium oxide, titanium oxide, indium oxide, and indium tin oxide (ITO). In addition to binary metal-oxygen compounds like ZnO, SnO₂, or In₂O₃, ternary metal-oxygen compounds such as Zn₂SnO₄, CdSnO₃, ZnSnO₃, MgIn₂O₄, GaInO₃, Zn₂In₂O₅, or In₄Sn₃O are also included. 12or mixtures of different transparent conductive oxides belong to the group of TCOs. Furthermore, TCOs do not necessarily have a stoichiometric composition and can also be p- or n-doped. Suitable metals for electrodes 14 and 16 can be selected from aluminum, barium, indium, silver, gold, magnesium, calcium, copper, and lithium, as well as compounds, combinations, and alloys thereof. The first electrode 14 can, for example, be configured as the anode, while the second electrode 16 can be configured as the cathode. With appropriate material selection, however, a configuration with reversed polarity is also possible.

[0039] The organic functional layer stack 15 can, in addition to at least one organic light-emitting layer, comprise further organic layers, for example, one or more layers selected from hole injection layers, hole transport layers, electron blocking layers, hole-blocking layers, electron transport layers, electron injection layers, and charge generation layers (CGLs) that are suitable for directing holes or electrons to the organic light-emitting layer or blocking the respective transport. Furthermore, multiple light-emitting layers may be present. The layers of the organic functional layer stack 15 can comprise organic polymers, organic oligomers, organic monomers, organic small non-polymeric molecules, or combinations thereof.In particular, it can be advantageous if the organic functional layer stack 15 includes a functional layer designed as a hole transport layer to enable effective hole injection into the at least one organic light-emitting layer. Suitable materials for a hole transport layer include, for example, tertiary amines, carbazole derivatives, conductive polyaniline, or polyethylene dioxythiophene. Suitable materials for the light-emitting layer include electroluminescent materials exhibiting radiation emission due to fluorescence or phosphorescence, such as polyfluorene, polythiophene, or polyphenylene, or derivatives, compounds, mixtures, or copolymers thereof.

[0040] The first electrode 14 is divided into at least two mechanically and electrically separated functional areas 141, i.e., two independently electrically contactable areas arranged laterally adjacent to each other on the first main surface 111. These at least two functional areas 141 allow for the formation of 20 separately operable luminescent segments of the organic light-emitting component 100 within the active area, thus segmenting the organic light-emitting component 100. More than the two functional areas 141 shown here are also possible. Each of the functional areas 141 can have a desired shape, which then determines the shape of the resulting luminescent segment.The organic functional layer stack 15 and the second electrode 16 are arranged contiguously above the first electrode 14 and thus contiguously above the at least two functional areas 141 of the first electrode 14. The functional areas 141 of the first electrode 14 and the second electrode 16 are each large-area, i.e., not pixel-shaped, so that the organic light-emitting component 100 is designed as a segmented area light source. The functional areas 141 preferably have an area greater than or equal to a few square millimeters, preferably greater than or equal to one square centimeter, and even greater than or equal to one square decimeter. The shapes of the functional areas 141 and, correspondingly, also of the active area 20 can be designed according to the desired luminescence pattern, for example, polygonal or round.Furthermore, it may also be possible, particularly in complex designs and especially with a large number of functional areas 141, that the organic functional layer stack 15 is subdivided into, for example, two or more non-contiguous areas, coarsely structured by a shadow mask, for instance. This may result in improved contact with the second electrode 16. Moreover, particularly in very complex designs, the second electrode 16 may also have more than one contiguous area and thus two or more segments.

[0041] The functional areas 141 can be separated from each other, for example, by an insulating layer 18 and / or by a lateral spacing. The insulating layer 18 can be formed, for example, by a polymer, such as an organic resist, i.e., a photoresist. Alternatively, an inorganic electrically insulating material is also possible, such as an oxide, nitride, or oxynitride, which are described above in connection with the base layer 12. Further features for the electrical insulation of the light-emitting segments from each other are described below in connection with the Fig. Sections 4A to 4C are explained. The functional areas 141 are particularly preferably able to have a lateral spacing of less than or equal to 100 µm, less than or equal to 50 µm, less than or equal to 25 µm, or greater than 0 µm. The segmentation of the organic light-emitting component 100 is thus achieved solely by segmenting the first electrode 14 into the at least two functional areas 141, whereby the described small spacings of 100 µm and less are possible.

[0042] For electrical contact between electrodes 14 and 16, a metallization layer 13 is provided, which in the illustrated embodiment is applied between the base layer 12 and the first electrode 14, and thus, viewed from the substrate 11, beneath the first electrode 14. The metallization layer 13 is in contact with the first electrode 14. In particular, the metallization layer 13 has direct contact with the first electrode 14 in a partial area. The metallization layer 13 is also in contact, particularly preferably in direct contact, with the second electrode 16. As shown in Fig. As can be seen in Figure 1, the metallization layer 13 is divided into electrically and mechanically separated areas that contact the functional areas 141 of the first electrode 14 and the second electrode 16 separately. Separated areas of the metallization layer 13 can be separated from each other like the functional areas 141 of the first electrode 14 and / or have distances from each other similar to the functional areas 141 of the first electrode 14. In the illustrated embodiment, the metallization layer 13 is arranged under the entire first electrode 14 and projects laterally in the edge region 21 under the first electrode 14 and the encapsulation 19 described below. The encapsulation 19 can be arranged at least partially in the edge region 21 directly on the metallization layer 13.

[0043] During the fabrication of the organic light-emitting device 100, the described layers can, for example, be applied in an unstructured manner. "Unstructured" in this context can also mean that a layer is roughly applied to a desired area using a shadow mask. Subsequently, one or more methods can be used to structure and precisely position the metallization layer 13, and in particular its separate regions, the first electrode 14, and especially its functional regions 141, as well as, optionally, the insulating layer 19. These methods can be selected from photolithography, printing techniques, laser techniques, or combinations thereof. Compared to conventional deposition methods, this allows for finer segment boundaries and a defined edge region with preferred dimensions.In particular, this allows for greater freedom in the design of the illuminated surface, for example with regard to complex shapes.

[0044] Exposed portions of the metallization layer 13 form electrode terminals 17 in connection areas of the organic light-emitting component 100 for the electrical connection of the organic light-emitting component 100 to an external power supply. Here, the separate portions of the metallization layer 13 each form at least one electrode terminal 17 in contact with each of the functional areas 141 of the first electrode 14 and with the second electrode 16. Accordingly, in the illustrated embodiment, the metallization layer 13 has at least three separate areas and thus three electrode terminals 17, two of which are located in the Fig. The metallization layer 13 can be seen in the cross-sectional view shown in Figure 1. As shown, it can be formed by a single metal layer, for example with Al and / or Cu, or by a stack of metal layers, for example Cr / Al / Cr, Mo / Al / Mo or Ag / Mg. Furthermore, the term "metallization layer" can also include combinations with a TCO layer and one or more metal layers.

[0045] An encapsulation 19 is arranged over the organic functional layer stack 15 and the electrodes 14, 16 to protect the organic functional layer stack 15 and the electrodes 14, 16. The encapsulation 19 is transparent to the light generated during operation of the organic light-emitting device 100, so that the light generated during operation can be emitted outwards through the transparent second electrode 16 and the encapsulation 19. The encapsulation 19 can form an outer layer of the device 100 facing away from the substrate 11, so that an outer surface of the encapsulation 19 can form a light-emitting surface of the device 100. Furthermore, it is also possible to apply a protective layer to the encapsulation 19, for example, made of a transparent plastic such as acrylic, as mechanical scratch protection, and / or another barrier film and / or optical structures to increase light emission.

[0046] The encapsulation 19 is designed, in particular, as a thin-film encapsulation. In this context, a thin-film encapsulation is understood to be a device suitable for forming a barrier against atmospheric substances, especially moisture and oxygen, and / or against other harmful substances such as corrosive gases, for example, oxygen and hydrogen sulfide. In other words, the thin-film encapsulation is designed such that it can be penetrated by atmospheric substances only to a very small extent. This barrier effect in the thin-film encapsulation is essentially generated by one or more barrier layers and / or passivation layers designed as thin films, which are part of the encapsulation 19.The encapsulation layers 19 typically have a thickness of less than or equal to a few micrometers or even less than or equal to a few hundred nm and are applied to the substrate 11 and the previously described additional layers.

[0047] In particular, the thin-film encapsulation can have or consist of one or more thin layers that are responsible for the barrier effect of the encapsulation. The thin layers can be applied, for example, by means of an atomic layer deposition (ALD) or molecular layer deposition (MLD) process. The encapsulation 19 is thus not formed by a self-supporting element, but is produced only by the deposition process. Suitable materials for the layers of the encapsulation arrangement can be, for example, aluminum oxide, zinc oxide, zirconium oxide, titanium oxide, hafnium oxide, lanthanum oxide, tantalum oxide, and the aforementioned TCOs, such as aluminum tin oxide. Preferably, the encapsulation has a layer sequence with a plurality of the thin layers, each having a thickness between one atomic layer and several hundred nm.

[0048] Alternatively or additionally to thin films produced by ALD or MLD, the encapsulation 19 can comprise at least one or more further layers, in particular barrier layers and / or passivation layers, which are deposited by thermal evaporation or by means of a plasma-enhanced process, such as sputtering, chemical vapor deposition (CVD), or plasma-enhanced chemical vapor deposition (PECVD). Suitable materials for this purpose can be the aforementioned materials as well as silicon nitride, silicon oxide, silicon oxynitride, indium tin oxide, indium zinc oxide, aluminum zinc oxide, aluminum oxide, and mixtures and alloys of the aforementioned materials. The one or more further layers can, for example, each have a thickness between 1 nm and 5 µm, and preferably between 1 nm and 400 nm, including the limits of this range.Furthermore, the encapsulation can also include one or more polymeric buffer layers between one or more pairs of adjacent layers of inorganic materials.

[0049] The encapsulation 19 covers, in particular, the active region 20 and the edge region 21, so that, together with the substrate 11, comprehensive protection, especially of the organic functional layer stack 15, can be achieved. Specifically, the encapsulation 19 can cover the first main surface 111 of the substrate 11, except for the electrical connection areas described above and thus for the electrode connection pieces 17. The encapsulation 19 can also extend to one or more edges or edge regions of the first main surface 111 of the substrate 11. The encapsulation 19 can also be applied, at least partially, directly to the base layer 12.Because the base layer 12, like the encapsulation 19, comprises an inorganic material such as an oxide, nitride, or oxynitride, very good adhesion of the encapsulation 19 to the base layer 12 can occur, allowing the edge region 21 to be very narrow in such a region. Furthermore, the base layer 12 and the encapsulation 19 can also be made of the same material, resulting in the same or similar coefficients of thermal expansion for both layers, which can further promote reliable adhesion.

[0050] The organic light-emitting device 100, which, according to the previously described structure, is designed as a flexible, top-side emitting, segmented OLED, can combine the characteristics of bendability and fine segmentation while offering the robustness required in the automotive sector. Its bendability exceeds that of conventional OLEDs with ultrathin glass substrates, while automotive robustness is more reliably and easily achieved than in the case of OLEDs on plastic films. In particular, the device 100 described here can be characterized as a bendable, robust, metal foil-based OLED with light-emitting segments exhibiting spacings of less than or equal to 100 µm, or even less than or equal to 50 µm, or even less than or equal to 25 µm.Furthermore, a defined distance between the active area, i.e., the luminescent surface, and the edge of the first main surface, and thus the edge of the substrate, is possible; this distance can be, for example, in the range of 1 to 2 mm or less. The described design makes it possible, in particular, to prevent delamination of the encapsulation in the edge region or to provide an encapsulation area in the edge region without drastically reducing the fill factor, i.e., the area ratio of the active area to the edge region.

[0051] The following figures show further embodiments that represent modifications and variations of the embodiment described above. The subsequent description therefore focuses primarily on the differences in features.

[0052] In Fig. Figure 2 shows a further embodiment of an organic light-emitting component 100, in which, compared to the embodiment of the Fig. 1 the metallization layer 13 is arranged laterally next to the first electrode 14. In this embodiment, as well as in the previous and the following embodiment, the metallization layer 13 can be at least partially identical to the first electrode 14.

[0053] In Fig. Figure 3 shows a further embodiment of an organic light-emitting component 100, in which the metallization layer 13 is arranged on the first electrode 14. In this embodiment, as well as in the previous embodiments, the metallization layer 13 can be arranged exclusively in the edge region 21, and the encapsulation 19 can be partially applied directly to the metallization layer 13.

[0054] In the Fig. Figures 4A to 4C show partial schematic representations of exemplary embodiments with regard to the mechanical and electrical separation of the functional areas 141 of the first electrode 14 together with the underlying metallization layer 13, as shown in Fig. 1 is shown, or only the functional areas 141 of the first electrode 14, as shown in the Fig. 2 and Fig. Figure 3 shows the segment boundaries and the edges of the luminescent surfaces. Furthermore, the embodiments also apply to separate areas of the metallization layer 13. Fig. In 4A to 4C, the uppermost layer, designated as the first electrode 14, can therefore also be the metallization layer, as indicated by the reference numeral 13 in parentheses. The following description applies accordingly to these cases as well.

[0055] As in Fig. As can be seen from 4A, the insulating layer 18 can fill the gap between the functional areas 141 and cover the edges of the first electrode 14 at the gap.

[0056] Alternatively, it is also possible that, as in Fig. As shown in Figure 4B, the insulating layer 18 precisely fills the gap. Alternatively, instead of an insulating layer 18 for separation, the separation can also be achieved by spacing, as shown in Figure 4B. Fig. As shown in Figure 4C. A flat taper of the electrode 14 allows for reliable over-formation of the gap edges with organic material and / or the second electrode and the encapsulation without the risk of defects. An advantageous aspect ratio of the depicted edge width 31 to the edge height 32 can, for example, be greater than or equal to 2, greater than or equal to 5, or greater than or equal to 10.

[0057] In Fig. Figure 5 shows a further embodiment of an organic light-emitting component 100 in a schematic top view in the vertical direction, i.e., in the direction of the first main surface of the substrate, whereby for the sake of clarity the organic functional layer stack 15 and the encapsulation 19 are not shown.

[0058] As in the previous embodiments, the substrate 11, formed by a metal foil, is covered with the base layer 12. The first electrode 14 is shown, purely by way of example, divided into two functional areas 141. The position of the transparent second electrode 16 is indicated by the dashed line. The shape of the substrate 11, the first electrode 14 and its functional areas 141, as well as the second electrode 16 and the insulating layer 18, are to be understood as purely exemplary. Furthermore, more than two functional areas 141 may also be present. The functional areas 141 are as described in connection with Fig. 4C is described by a spacing that separates the functional areas electrically and mechanically from one another. Alternatively, separation can also be achieved by an insulating layer 18. The width of the segment boundary, i.e., the distance between the functional areas 141, is less than or equal to 100 µm, or less than or equal to 50 µm, or even less than or equal to 25 µm, and can be determined by the combination of the Fig. The described procedure can be achieved.

[0059] Furthermore, a metallization layer 13 is present, which, as in connection with the Fig. 1 to 3 described can be arranged at least partially on, next to, or below the first electrode 14. The metallization layer 13 is divided into three separate regions. Each of the regions, which is also divided by a Fig. The spacing shown in Figure 4C, with a distance of less than or equal to 100 µm, less than or equal to 50 µm, or less than or equal to 25 µm, forms at least a partial electrode connection 17 for each of the functional areas 141 of the first electrode 14, shown in the illustration in an upper and lower connection area of ​​the substrate 11, and for the second electrode 16, shown in the illustration in a left connection area of ​​the substrate 11. The incorporated so-called turn-around structure shown in the connection area for the second electrode 16 is optional and may also be omitted. Furthermore, fine comb structures are also possible in the transition area between the metallization layer 13 and the second electrode 16 (not shown).Furthermore, markings 130, so-called alignment marks, can also be present in the electrode connection pieces 17, as indicated in the upper connection area of ​​the illustration. These markings can, for example, facilitate the alignment of an external connection element such as a flexible printed circuit board, also known as a FlexPCB. The alignment marks can also be separate from the other surfaces of layer 13; that is, instead of notches or recesses as shown in the example, crosses or other shapes may be present, as shown in the illustration in [reference missing]. Fig. 5, for example, in the otherwise free areas in the top left and / or bottom left corners.

[0060] The three-sided, rib-shaped insulating layer 18, which electrically insulates the first and second electrodes from each other in the edge region of the organic functional layer stack and essentially defines the position of the organic functional layer stack, can have a width greater than or equal to 500 µm or greater than or equal to 1 mm and less than or equal to 2 mm. Alternatively, with a suitable geometric design of the electrodes and the organic functional layer stack, no insulating layer 18 may be present. At the substrate edge on the right in the illustration, the distance between the first electrode 14 and the substrate edge can preferably be greater than or equal to 50 µm and less than or equal to 150 µm.The distance of the active area, and thus the luminescent surface, from the right edge of the substrate shown in the illustration can preferably be greater than or equal to 100 µm and less than or equal to 4 mm, or greater than or equal to 200 µm and less than or equal to 3 mm, or greater than or equal to 500 µm and less than or equal to 2 mm. This ensures that the non-luminescent edge area is very small in the regions of the component 100 where no electrode connection 17 is provided.

[0061] The embodiments shown in conjunction with the figures can also be combined with one another according to further embodiments, even if not all such combinations are explicitly described in conjunction with the figures. Furthermore, the embodiments shown in the figures may additionally or alternatively have features according to the general description. Reference symbol list 11 Substrat 12 Base layer 13 Metallization layer 14 electrode 15 organic functional layer stacks 16 electrode 17 Electrode connection piece 18 Insulator layer 19 Encapsulation 20 active area 21 Edge area 31 width 32 Height 100 organic light-emitting components 111 first main surface 112 second main surface 130 markers 141 Functional area

Claims

[1] Organic light-emitting device (100), comprising - a flexible substrate (11) with a first main surface (111) comprising a metal foil, - an inorganic electrically insulating base layer (12) on the first main surface (111), - in an active area (20) a first electrode (14), an organic functional layer stack (15) and a transparent second electrode (16) on the base layer (12) and - a transparent encapsulation (19) over the active area (20) and a marginal area (21) surrounding the active area (20) in a lateral direction, wherein - the first electrode (14) is divided into at least two mechanically and electrically separated functional areas (141) and - the second electrode (16) is arranged continuously over the at least two functional areas (141), wherein - the organic functional layer stack (15) is applied continuously over the functional areas (141) of the first electrode (14), - the functional areas (141) are separated from each other by a lateral spacing, and - the first electrode (14) tapers off flat, with an aspect ratio of edge width (31) to edge height (32) greater than or equal to 2. [2] Component (100) according to claim 1, wherein the at least two functional areas (141) have a distance of less than or equal to 100 µm from each other. [3] Component (100) according to one of the preceding claims, wherein a metallization layer (13) is applied in contact with the first electrode (14). [4] Component (100) according to the preceding claim, wherein the metallization layer (13) protrudes in a lateral direction below the encapsulation (19). [5] Component (100) according to claim 3 or 4, wherein the encapsulation (19) is arranged at least partially in the edge region (21) directly on the metallization layer (13). [6] Component (100) according to one of claims 3 to 5, wherein the metallization layer (13) is arranged between the first electrode (14) and the base layer (12). [7] Component (100) according to claim 6, wherein the metallization layer (13) is arranged under the entire first electrode (14) as seen from the substrate (11). [8] Component (100) according to one of claims 3 to 5, wherein the metallization layer (13) is arranged on the first electrode (14) in the edge region (21) as seen from the substrate (11). [9] Component (100) according to one of claims 3 to 8, wherein the metallization layer (13) is arranged in a lateral direction next to the first electrode (14). [10] Component (100) according to one of claims 3 to 9, wherein at least a part of the metallization layer (13) forms an electrode connection (17) for connecting the organic light-emitting component (100) to an external power and / or voltage supply. [11] Component (100) according to claim 10, wherein separate parts of the metallization layer (13) each form at least one electrode connection piece (17) and each of the electrode connection pieces (17) is in contact with one of the functional areas (141) of the first electrode (14) and with the second electrode (16). [12] Component (100) according to one of the preceding claims, wherein the base layer (12) projects laterally below the encapsulation (19). [13] Component (100) according to one of the preceding claims, wherein the base layer (12) covers the entire first main surface (111) of the substrate (11). [14] Component (100) according to one of the preceding claims, wherein the encapsulation (19) is arranged at least partially in the edge region (21) directly on the base layer (12). [15] Component (100) according to the previous claim, wherein the base layer (12) and the encapsulation (19) are of the same material. [16] Component (100) according to one of the preceding claims, wherein the encapsulation (19) is a thin-film encapsulation. [17] Component (100) according to one of the preceding claims, wherein a distance between an edge of the first main surface (111) of the substrate (11) and the active area (20) is less than or equal to 4 mm. [18] Method for producing an organic light-emitting device (100) in which one or more methods selected from photolithography, printing techniques, laser techniques and combinations thereof are used to structure a metallization layer (13) and / or a first electrode (14), wherein an organic light-emitting device (100) is produced according to any one of claims 1 to 17.

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