Method for producing an organic light-emitting diode and organic light-emitting diode

Abstract

Method for producing at least one organic light-emitting diode (1) comprising the steps: A) Providing a film (2) as a permanent, flexible substrate for the organic light-emitting diode (1), wherein the film (2) has a film underside (23) and a film topside (25) opposite it, C) Applying an adhesive layer (33) directly and over a large area to the underside of the film (23), wherein the adhesive layer (33) is covered on one side facing away from the film (2) by a protective cover (31), D) Structuring and partially removing the protective cover (31) so that the adhesive layer (33) is exposed in at least one adhesion area (34) and so that the protective cover (31) remains on the adhesive layer (33) in at least one assembly area (35), E) Attaching a temporary intermediate carrier (4) in the adhesive area (34) directly to the adhesive layer (33), so that in the mounting area (35) the protective cover (31) is located between the adhesive layer (33) and the intermediate carrier (4), G) Generating an organic layer sequence (5) for light generation at the top of the film (25), and H) Detaching the bonding area (34) and subsequently removing the intermediate support (4).

Description

[0001] A method for manufacturing an organic light-emitting diode (OLED) is described. Furthermore, an organic light-emitting diode is described.

[0002] One problem to be solved is to specify an organic light-emitting diode that is efficient to mount and suitable for elevated operating temperatures.

[0003] This problem is solved, among other things, by a method and by an organic light-emitting diode (OLED) with the features of the independent claims. Preferred embodiments are the subject of the dependent claims.

[0004] Organic light-emitting diodes and their manufacturing processes are known from US 2005 / 0 090 075 A1, US 2005 / 0 129 841 A1, US 2015 / 0 075 705 A1, WO 2016 / 176 037 A1 and DE 10 2015 107 588 A1.

[0005] According to at least one embodiment, the method comprises the step of providing a film. The film is a permanent, flexible substrate for the organic light-emitting diode to be produced. Preferably, the film is a metal film; however, other films, such as those made of glass or plastic, or even composite films made of several different materials, can also be used.

[0006] Furthermore, the film is preferably the component of the finished organic light-emitting diode (OLED) that mechanically supports and holds the OLED together. The fact that the film, and preferably also the OLED, is mechanically flexible can mean that bending radii of 20 mm or less are possible without damaging the finished OLED.

[0007] According to at least one embodiment, the film has a bottom surface and a top surface opposite it. Preferably, the bottom surface and the top surface are smooth and / or flat, so that there is no targeted structuring of the bottom surface and / or the top surface in or on the film. For example, the top surface and / or the bottom surface have an average roughness of at least 5 nm or 50 nm or 0.1 µm and / or of at most 0.4 µm or 1 µm.

[0008] According to at least one embodiment, the method comprises the step of applying an adhesive layer to the underside of the film. The adhesive layer is preferably applied directly and over a large area, particularly the entire surface, to the underside of the film. This can mean that the entire underside of the film is directly covered by the adhesive layer, preferably with a constant, uniform thickness. The adhesive layer is based, for example, on a silicone, a urethane or polyurethane, an epoxy, an acrylate or polyacrylate, or on a combination of the aforementioned materials.

[0009] According to at least one embodiment, the adhesive layer is covered by a protective liner on the side facing away from the film when applied to the film. The protective liner can be located directly on the adhesive layer. Preferably, the entire adhesive layer is covered by the protective liner. The protective liner, also referred to as a liner, can preferably be peeled off the finished organic light-emitting diode without damaging the adhesive layer or other components of the diode. In other words, the protective liner adheres only weakly to the adhesive layer.

[0010] According to at least one embodiment, the method comprises the step of structuring and partially removing the protective cover. That is, the adhesive layer is exposed in at least one adhesion area, and the protective cover is removed from the adhesive layer in this adhesion area. In addition, at least one mounting area is formed, in which the protective cover remains attached to the adhesive layer. In particular, all areas where the protective cover remains attached to the adhesive layer can be considered mounting areas, and all areas from which the protective cover has been removed can be considered adhesion areas. Due to the protective cover, the adhesive layer acts adhesively in the at least one adhesion area and non-adhesively in the at least one mounting area. In particular, the protective cover does not exhibit any adhesive effect on a side facing away from the adhesive layer.

[0011] According to at least one embodiment, an intermediate support is applied to the film. The intermediate support is preferably a mechanically rigid or barely flexible support, for example, a glass plate. Alternatively, the intermediate support can be designed as a carrier film, preferably a relatively rigid carrier film, to enable a roll-to-roll manufacturing process. Furthermore, the intermediate support is preferably temperature-stable, for example, up to temperatures of at least 200 °C or 300 °C. In addition, the intermediate support is preferably only temporarily attached to the metal film, so that the intermediate support is no longer present in the finished organic light-emitting diode.

[0012] According to at least one embodiment, the intermediate support is applied across the entire surface of the film. This means that the underside of the film can be completely covered by the intermediate support.

[0013] According to at least one embodiment, the intermediate carrier is located directly adjacent to the adhesive layer in the adhesion area. In the mounting area, the protective cover is situated between the adhesive layer and the intermediate carrier. Preferably, the intermediate carrier extends continuously and seamlessly across both the mounting area and the adhesion area. However, the intermediate carrier adheres to the adhesive layer, and thus also to the film, only in the adhesion area.

[0014] According to at least one embodiment, the method includes the step of producing an organic layer sequence. The organic layer sequence is designed to generate light, for example, colored light such as blue light or white light. For this purpose, the organic layer sequence can contain one or more active layers in which charge carrier recombination and electroluminescence occur. Optionally, the organic layer sequence and / or the organic light-emitting diode can contain phosphors that generate radiation via photoluminescence. The organic layer sequence is applied directly or indirectly to the top surface of the film.

[0015] According to at least one embodiment, the method includes the step of separating the adhesive area. This is followed by the removal of the intermediate carrier. Separating the adhesive area means, in particular, that the adhesive layer, viewed from above, is cut between the mounting area and the adhesive area, for example, by cutting and / or laser treatment. Alternatively or additionally, this means that the film is cut, also for example, by laser treatment or mechanical cutting, so that only the mounting area remains on the finished organic light-emitting diodes (OLEDs), and the adhesive area is eliminated. By separating the adhesive area, the remaining areas of the film, outside the OLEDs, no longer adhere to the intermediate carrier. This allows for easy, virtually force-free removal of the OLEDs from the intermediate carrier.

[0016] In at least one embodiment, the method for producing one or, preferably, several organic light-emitting diodes is set up and comprises the following steps, in particular in the order given: A) Providing a film as a permanent, flexible substrate for the organic light-emitting diode, wherein the film has a bottom surface and a top surface opposite it, C) Applying an adhesive layer directly and over the entire surface of the underside of the film, wherein the adhesive layer is covered by a protective cover on one side facing away from the film, D) Structuring and partially removing the protective cover so that the adhesive layer is exposed in at least one adhesion area and so that the protective cover remains on the adhesive layer in at least one mounting area, E) Attaching a temporary, preferably mechanically rigid, intermediate support in the bonding area directly to the adhesive layer, so that the protective cover is located between the adhesive layer and the intermediate support in the assembly area, G) Creating an organic layer sequence for light generation on the top surface of the film, and H) Detaching the bonding area and subsequently removing the intermediate support.

[0017] Flexible organic light-emitting diodes (OLEDs) require a substrate that is as robust as possible, especially when the OLED is used in demanding environments such as the automotive sector. Robustness means, for example, that the substrate is resistant to temperature fluctuations, vibrations, and environmental influences, while simultaneously allowing for mechanical flexibility and bendability. Particularly in the automotive sector, comparatively high temperatures can occur temporarily. To prevent materials used in the OLED, such as electrically insulating coatings (e.g., polyimide-based), from damaging the organic layer sequence through outgassing of components and / or solvents, these components must be baked out during the OLED manufacturing process.The baking temperatures must reach, and preferably exceed, the subsequent operating temperature to prevent outgassing. For this purpose, baking temperatures of at least 150 °C or 200 °C are required.

[0018] Since the film used as a substrate is mechanically flexible and relatively thin, an intermediate support is required during the production of the organic light-emitting diode (OLED) to ensure, for example, the uniform deposition of the organic layer sequence and efficient processing of the OLED. However, when using thin films, the challenge lies in not damaging or destroying the film during the removal process after the OLED has been manufactured. Therefore, only very minimal force must be applied when removing the film from the intermediate support to avoid plastically deforming and / or damaging the OLED, for example, by creasing it.

[0019] This virtually effortless removal of the finished organic light-emitting diode (OLED) and the metal foil from the intermediate carrier is achieved by dividing the adhesive layer into a mounting area that remains attached to the OLED and an adhesive area that remains attached to the intermediate carrier. Furthermore, the protective cover enables a self-adhesive, efficiently mountable OLED. This eliminates the need for any additional joining solution or complex assembly when the OLED is installed by the end customer.

[0020] According to at least one embodiment, the method comprises a step B). Step B) preferably precedes step C). In step B), the adhesive layer is provided. The adhesive layer is located between the protective cover and a protective layer. The protective cover and the protective layer can be made of the same or different materials and have the same or different thicknesses. Preferably, the protective cover and the protective layer are identical within the manufacturing tolerances.

[0021] According to at least one embodiment, in step B) the adhesive layer is provided together with the protective cover and the protective layer in the form of a double-sided adhesive film or double-sided adhesive tape. That is, the adhesive layer is adhesive on both sides when the protective cover and the protective layer are removed. Accordingly, the protective cover and the protective layer themselves can be easily removed from the adhesive layer and serve only as temporary protection for the adhesive layer.

[0022] According to at least one embodiment, the adhesive layer and the protective cover remain in the finished organic light-emitting diode (OLED) after step H). After the protective cover is subsequently removed, the adhesive layer serves as a mounting medium for the OLED. This allows the OLED to be mounted using a self-adhesive method. That is, when the OLED is mounted, the adhesive layer is preferably located directly on the film and on an external mounting platform that is not part of the OLED. The protective cover is no longer present once the OLED is mounted. Therefore, the protective cover is removed before the OLED is mounted.

[0023] According to at least one embodiment, the method comprises a step F). In step F), an insulating layer is created on the top surface of the film, either partially or across its entire surface. The insulating layer can either partially or completely touch the top surface or be separated from the film by at least one further layer.

[0024] Preferably, step F) is performed between steps E) and G).

[0025] According to at least one embodiment, the insulating layer is made of an organic material and is preferably based on a plastic and / or a polymer such as a polyimide, epoxy, and / or an acrylate. The insulating layer is applied to the film, for example, as a liquid lacquer.

[0026] According to at least one embodiment, the production of the insulating layer comprises one or more bake-out steps. During bake-out, an insulating layer material, which is applied particularly in a liquid state, is cured and / or dried and / or polymerized. During bake-out, volatile components of the insulating layer material and / or solvents are released. Bake-out preferably takes place at a temperature higher than a subsequent operating temperature of the organic light-emitting diode, for example, at least 30 °C, 50 °C, or 80 °C higher than the subsequent intended maximum operating temperature.

[0027] According to at least one embodiment, the protective cover is temperature-stable. This means, in particular, that the protective cover withstands the at least one heating-up step for the insulation layer without damage. Temperature stability means, in particular, that shrinkage of the protective cover is negligible. For example, the shrinkage of the protective cover during heating is at most 3%, 2%, or 1%. This applies especially at a temperature of at least 130°C, 150°C, or 200°C, and preferably for a duration of this temperature exposure of at least 1.5 hours, 2 hours, or 3 hours. The corresponding durations and / or temperatures can correspond to the heating-up step of the insulation layer.

[0028] According to at least one embodiment, the adhesive area surrounds the mounting area completely, in particular entirely and in a frame-like manner. This is preferably the case when viewed from above on the underside of the film. Viewed from above, the adhesive area is particularly preferably located outside the organic light-emitting diode (OLED). In other words, the adhesive area can also completely surround the OLED in a frame-like manner. The mounting area and the OLED can be arranged congruently.

[0029] According to at least one embodiment, the method is used to produce a plurality of organic light-emitting diodes (OLEDs) together. In particular, up to step E), the OLEDs have a common, continuous and / or uninterrupted film that serves as a substrate for the respective OLEDs.

[0030] According to at least one embodiment, the organic light-emitting diodes (OLEDs) are surrounded by a common adhesive area up to step H), as viewed from above. This means that the OLEDs can lie completely on the continuous mounting area, which is common up to step H). Within this mounting area, adjacent OLEDs can directly abut each other. This means that an adhesive area between adjacent OLEDs is not required, leaving only the outer, circumferential frame-shaped adhesive area. Alternatively, it is possible that an adhesive area is also present between at least some of the OLEDs.

[0031] According to at least one embodiment, the adhesive layer remains as a continuous, uninterrupted layer until step H). This means that only in step H) is the adhesive layer, preferably together with the protective cover and preferably congruent with the organic light-emitting diode(s), cut. Cutting the protective cover preferably only occurs if adjacent organic light-emitting diodes are mounted and produced in a common mounting area up to step H) without an intervening adhesive area.

[0032] According to at least one embodiment, in step D) the adhesive layer is divided into the assembly area and the bonding area together with the protective cover. This means that the adhesive layer is divided before the bonding area is separated. When the bonding area is separated, the film and any other continuously applied components are separated, particularly within the manufacturing tolerances, and this separation is congruent with the division of the adhesive layer that occurred in step D).

[0033] According to at least one embodiment, the protective cover comprises or consists of one or more of the following materials, which are in particular temperature-stable plastics: polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polyurethane (PUR), epoxy, polyacrylate, polyvinyl chloride (PVC), polyimide (PI), polytetrafluoroethylene (PTFE), polyethylene naphthalate (PEN), polyetheretherketone (PEEK), and silicone. The thickness of the protective cover is preferably at least 2 µm, 5 µm, or 10 µm, or at most 100 µm, 50 µm, or 30 µm.

[0034] According to at least one embodiment, the adhesive layer has a thickness of at least 10 µm, 15 µm, or 25 µm. Alternatively or additionally, the thickness of the adhesive layer is at most 1 mm, 0.5 mm, or 0.3 mm.

[0035] According to at least one embodiment, the adhesive layer is relatively thick compared to the protective cover. In particular, the thickness of the adhesive layer exceeds the thickness of the protective cover by at least a factor of 2, 3, 5, or 10.

[0036] According to at least one embodiment, the adhesive layer is mechanically deformable, in particular elastically deformable. This makes it possible for the adhesive layer to act as a buffer, so that after step E) in step G) the top surface of the film is flat with a tolerance of at most 20%, 10%, or 5% of the average thickness of the protective cover. In other words, the adhesive layer can compensate for the thickness of the protective cover, so that the underside and the top surface of the film are equidistant from the intermediate support.

[0037] According to at least one embodiment, the foil is a metal foil and comprises or consists of one or more of the following materials: aluminum, silver, gold, chromium, molybdenum, titanium, copper, iron, nickel, vanadium. Preferably, the foil is an aluminum foil or a foil made of stainless steel. Alternatively or additionally, the foil has a thickness of at least 20 µm or 40 µm and / or at most 0.2 mm or 0.1 mm or 60 µm.

[0038] As an alternative to metals, the film can be made of a plastic or a plastic coated with a metal. The metals listed in the preceding paragraph can serve as coating metals, either on one or both sides. The plastic of the film is, in particular, polyimide, polytetrafluoroethylene, polyethylene naphthalate, polyetheretherketone, silicone, or mixtures thereof. Otherwise, the same applies to such plastic films as described in connection with metal films.

[0039] According to at least one embodiment, the organic layer sequence is produced between two electrodes. Preferably, one of the electrodes is in direct electrical contact with the film or is formed by the film itself. Direct electrical contact refers in particular to a short circuit and / or an ohmic contact.

[0040] According to at least one embodiment, at least one encapsulation is produced on a side of the organic layer sequence facing away from the film, preferably before step H). In particular, a combined encapsulation is produced, which is composed, for example, of an inorganic thin-film encapsulation and an organic scratch-resistant layer. The thin-film encapsulation is produced, for example, by chemical vapor deposition (CVD) or atomic layer deposition (ALD). The thin-film encapsulation has a thickness of at least 20 nm or 40 nm and / or at most 200 nm or 120 nm. In contrast, the scratch-resistant layer can be produced, for example, by spin coating, printing, or spraying. The scratch-resistant layer preferably has a thickness of at least 500 nm, 5 µm, or 50 µm. Alternatively or additionally, the thickness of the scratch-resistant layer is at most 200 µm or 100 µm.

[0041] According to at least one embodiment, the adhesive layer, the film, and the encapsulation, particularly the scratch-resistant layer, together act as a laminate. The combination of these three materials preferably increases the stiffness and bending strength of the organic light-emitting diode (OLED) compared to the presence of only some of these layers. Preferably, the bending strength of the OLED is increased by at least a factor of 1.5, 2, or 4 by the presence of the adhesive layer, particularly in combination with the cover layer, compared to an identical component without an adhesive layer and without a cover layer.

[0042] Furthermore, an organic light-emitting diode (OLED) is specified. The OLED is preferably produced using a method as described in connection with one or more of the embodiments mentioned above. Features of the method are therefore also disclosed for the OLED, and vice versa.

[0043] In at least one embodiment, the organic light-emitting diode comprises the following components, which can follow one another directly or indirectly along a main emission direction of the organic light-emitting diode: a protective cover, a solid adhesive layer for self-adhesive attachment of the organic light-emitting diode, a film as a permanent flexible substrate, an insulating layer, an organic layer sequence for light generation, and at least one encapsulation.

[0044] The adhesive layer is preferably designed as a vibration damping layer for the mounted, attached organic light-emitting diode (OLED). In particular, the adhesive layer dampens relatively high-frequency vibrations. For this purpose, the adhesive layer material preferably has a modulus of elasticity of at most 5 MPa or 1 MPa at a temperature of 300 K. Alternatively or additionally, the thickness of the adhesive layer is at least 0.1 mm or 0.2 mm. The vibration damping is achieved through the low modulus of elasticity in combination with the comparatively large thickness of the adhesive layer.

[0045] The following section provides a more detailed explanation of the method and organic light-emitting diode described herein, with reference to the drawing and illustrated examples. Identical reference symbols indicate identical elements in the individual figures. However, the figures are not to scale; rather, individual elements may be exaggerated for clarity.

[0046] They show: Fig. 1. Perspective representations of process steps of a process described here for the production of an organic light-emitting diode described here. Fig. 2 schematic top views of exemplary embodiments of the organic light-emitting diodes described here on a common substrate, Fig. 3 schematic sectional views of exemplary embodiments of films on an intermediate carrier for a method described here, and Fig. 4 schematic sectional views of exemplary embodiments of the organic light-emitting diodes described here.

[0047] In Fig. Figure 1 illustrates a method for producing an organic light-emitting diode. According to Fig. 1A A double-sided adhesive film 3 is provided. The adhesive film 3 comprises an adhesive layer 33, which is formed, for example, from an acrylate or silicone. On opposite main sides of the adhesive layer 33 are a protective cover 31 and a protective layer 32. The protective cover 31 and the protective layer 32 can be identical in shape. Such protective covers 31 and protective layers 32 are also referred to as liners.

[0048] For example, the protective cover 31 and the protective layer 32 are polyimide layers with a thickness of 10 µm. The intervening adhesive layer 33, for example, has a thickness of 100 µm and is significantly thicker than the protective cover 31 and the protective layer 32. The protective cover 31 and the protective layer 32 preferably cover the main sides of the adhesive layer 33 completely and entirely.

[0049] For example, adhesive film 3 is a VHB adhesive film from the manufacturer 3M.

[0050] In Fig. Figure 1B shows that the protective layer 32 is separated from the adhesive layer 33. The adhesive layer 33 is applied directly to the underside 23 of a film 2. The film 2 is, for example, an aluminum foil with a thickness of 75 µm. A top surface 25 opposite the underside 23 is planar and flat and is not yet covered by any other components in this process step. The top surface 25 may be located on a substrate (not shown).

[0051] In the procedural step of Fig. In step 1C, a separation line S is generated in the protective cover 31. The separation line S preferably completely cuts through the protective cover 31. The adhesive layer 33 is preferably not affected by the separation line S. Alternatively, the separation line S can cut through both the protective cover 31 and the adhesive layer 33.

[0052] The separation line S runs in a frame-like shape around a mounting area 35 of the protective cover 31, see Fig. 1D. In the mounting area 35, the protective cover 31 remains attached to the adhesive layer 33. In contrast, outside the mounting area 35, the protective cover 31 is removed from a surrounding, frame-shaped adhesive area 34. The adhesive layer 33 is exposed in the adhesive area 34.

[0053] In the procedural step of Fig. In step 1E, an intermediate carrier 4 is attached to the film 2. The intermediate carrier 4 is preferably a mechanically rigid glass plate, for example with a thickness of 2 mm, which does not bend during the further manufacturing process. The intermediate carrier 4 is in contact with the adhesive layer 33 only in the adhesion area 34 and thus adheres to the adhesive layer 33 only in the adhesion area 34. In the assembly area 35 with the protective cover 31, no adhesive bond is formed between the intermediate carrier 4 and the film 2.

[0054] According to Fig. In step 1F, an organic layer sequence 5 is produced on the upper surface 25 of the film, which faces away from the intermediate support 4. The organic layer sequence 5 comprises at least one active layer for generating light during operation of the finished organic light-emitting diode. The organic layer sequence 5 can be deposited over the entire surface or, preferably, in a structured manner on the film 2.

[0055] In Fig. Figure 1G shows that further separation lines S are generated, for example, by means of a laser beam L. These further separation lines S form a grid-like pattern. One of the organic light-emitting diodes 1 is located within each sub-area of ​​the grid. The organic light-emitting diodes 1 as a whole are aligned with the mounting area 35 within the manufacturing tolerances.

[0056] The further separation lines S divide the organic layer sequence 5, the film 2, the adhesive layer 33, and the protective cover 31 between the organic light-emitting diodes 1. The outer further separation line S, which surrounds all organic light-emitting diodes 1, preferably runs concurrently or approximately concurrently with the separation line S from Fig. 1C. Thus, the adhesion area 34 is separated from the organic light-emitting diodes 1, which are located within the outer frame of the further separation line S.

[0057] This allows the individual organic light-emitting diodes 1, see Fig. 1H, without significant force being applied to the intermediate carrier 4. The adhesive area 34, which is firmly bonded to the intermediate carrier 4, remains attached to the intermediate carrier 4. Thus, the organic light-emitting diodes 1 are formed from the organic layer sequence 5, the film 2, the adhesive layer 33, and the protective cover 31.

[0058] Other components of the organic light-emitting diode 1, such as electrodes, electrical insulation layers to prevent short circuits within the organic light-emitting diode, external electrical contact surfaces, or encapsulation layers, are omitted for the sake of simplicity in the illustration. Fig. 1 not illustrated.

[0059] By using the double-sided adhesive film 3 and dividing it into the adhesive area 34 and the mounting area 35 with the protective cover 31, it is possible to attach the intermediate carrier 4 to the film 2 cost-effectively and with minimal effort, without damaging or removing the finished organic light-emitting diodes 1. This is particularly relevant because the film 2, and thus the organic light-emitting diodes 1, are relatively sensitive to creasing or bending damage, which would otherwise occur if they were removed from the intermediate carrier 4, requiring relatively large forces.

[0060] In Fig. Figure 1I shows the mounted organic light-emitting diode 1. The organic light-emitting diode 1 is adhered to an external mounting platform 9. To mount the organic light-emitting diode 1, the protective cover 31 is removed from the adhesive layer 33, and the organic light-emitting diode 1 can preferably be adhered to the external mounting platform 9 without additional tools. Again, for the sake of simplicity, the electrical connections are not shown.

[0061] In Fig. Figure 2 shows different top views of the organic layer sequence 5, analogous to the process step of the Fig. 1G. The in Fig. The further separation lines S shown in 2 can accordingly be used in the same way in all other embodiments, in particular in the method of Fig. 1. Use it.

[0062] According to Fig. 2A The organic light-emitting diodes 1 are grouped, for example, in pairs. Between adjacent groups are relatively narrow struts of the adhesive area 34. Thus, an adhesive bond exists between the intermediate carrier 4 and the film 2 even in these narrow struts between the groups of organic light-emitting diodes 1.

[0063] In contrast, according to Fig. 2B the organic light-emitting diodes 1 are not grouped together, but separated from each other. Between adjacent organic light-emitting diodes 1 there is a bridge of the adhesive area 34.

[0064] In Fig. Figure 2C illustrates that the organic light-emitting diodes 1 are formed from a continuous mounting area 35. The adhesive area 34 is formed, on the one hand, by a border that surrounds all the organic light-emitting diodes 1. Furthermore, there are island-shaped areas of the adhesive area 34, each bordering four of the organic light-emitting diodes 1. These island-shaped areas of the adhesive area 34 are thus located at the corners of the organic light-emitting diodes 1. For this purpose, the corners of the organic light-emitting diodes 1, viewed from above, can, for example, be chamfered, so that the organic light-emitting diodes 1 have an approximately octagonal base.

[0065] In Fig. Figure 3 illustrates sectional views of the film 2 on the intermediate support 4. These sectional views correspond in particular to the process step as shown in Fig. 1E illustrates. The in Fig. The three possibilities presented can each be used, in particular, in the process of Fig. 1 must be realized.

[0066] According to Fig. 3A The adhesive layer 33 is made of a comparatively soft, elastic material. This makes it possible to compensate for a height difference caused by the protective cover 31 present in the mounting area 35. In other words, the protective cover 31 is pressed into the adhesive layer 33. This allows the underside 23 and the top side 25 of the film to run parallel to a main surface of the intermediate carrier 4 facing the film 2 and to be planar and flat.

[0067] In contrast, in Fig. Figure 3B illustrates that the film 2 is slightly bent in a transition area between the mounting area 35 and the adhesive area 34. The film 2 thus forms a surface profile of the protective cover 31. In areas directly above the protective cover 31, congruent with the later, finished organic light-emitting diodes 1, the top surface 25 of the film is flat, so that the bends in the film 2 have no or no significant influence on the further manufacturing of the organic light-emitting diode 1, in particular on the application of the organic layer sequence 5. In cross-section, cavities may be formed laterally next to the protective cover 31 and between the adhesive layer 33 and the intermediate carrier 4. Unlike in Fig. As shown in 3B, it is also possible that no such cavities are present.

[0068] In the exemplary embodiment of the Fig. 3C has recesses in the intermediate carrier 4, which are designed to receive the protective cover 31. This ensures that the underside 23 of the film, the top side 25 of the film, and both main sides of the adhesive layer 33 are flat and planar. The recesses in the intermediate carrier 4 can be larger than the protective cover 31 itself, so that cavities can optionally be formed laterally next to the protective cover 31.

[0069] In Fig. Figure 4 shows an embodiment of the organic light-emitting diode 1. It illustrates how optionally included additional components of the organic light-emitting diode 1 can be designed. The adhesive layer 33 and the protective cover 31 are located on the underside 23 of the film. The adhesive layer 33 is relatively thick and made of a relatively soft material with a low modulus of elasticity. This allows the adhesive layer 33 to act as a buffer layer in the mounted organic light-emitting diode 1, compensating for unevenness on a mounting platform and also damping vibrations. The protective cover 31, the adhesive layer 33, and the film 2 are flush with each other laterally.

[0070] An optional first electrode 71 is located on the top surface 25 of the film. The first electrode 71 is formed, for example, by metallization. This function can also be performed by the film 2 itself. The organic layer sequence 5 is located on the first electrode 71. Viewed from above, the organic layer sequence 5 is surrounded by an insulating layer 6. The insulating layer 6 is applied and processed before the organic layer sequence 5. In particular, the insulating layer 6 is made of a polyimide lacquer or an acrylic lacquer. A bake-out step is required to process the insulating layer 6, which takes place at comparatively high temperatures. The adhesive layer 33 and, in particular, the protective cover 31 are designed to withstand the temperatures required during the processing of the insulating layer 6.

[0071] On one side of the organic layer sequence 5 facing away from the foil 2, there is a translucent second electrode 72. The second electrode 72 is separated from the metallic, electrically conductive foil 2 by the insulating layer 6.

[0072] The organic layer sequence 5 and the electrodes 71, 72 are surrounded by an encapsulation 8, with the exception of external electrical contact surfaces. The encapsulation 8 consists, for example, of a thin-film encapsulation 81 with a thickness of a few tens of nanometers, for example, made of aluminum oxide. Furthermore, a scratch-resistant layer 82 is present, for example, a lacquer, with a thickness on the order of several hundred micrometers. Optionally, a cover film 83, for example, in the form of an adhesive film, is also present.

[0073] The radiation generated during the operation of the organic light-emitting diode 1 passes through the encapsulation 8 and the second electrode 72 along a main emission direction E.

[0074] In the illustrated embodiments, an opaque, electrically conductive metal foil is used as film 2. However, transparent, electrically insulating polymer-based films can also be used for organic light-emitting diodes 1 emitting light through film 2. This applies in particular if the adhesive layer 33 and the mounting platform are, for example, Fig. 1I, are also transparent and translucent.

[0075] Unless otherwise indicated, the components shown in the figures preferably follow one another in the specified order. Layers that do not touch each other in the figures are preferably spaced apart. Where lines are drawn parallel to each other, the corresponding surfaces are also parallel to each other. Also, unless otherwise indicated, the relative thickness ratios, length ratios, and positions of the drawn components are correctly represented in the figures. Reference symbol list 1 organic light-emitting diode Slide 2 23 Underside of slides 25 Top of slide 3 double-sided adhesive films 31 Protective cover 32 Protective layer 33 adhesive layer 34 Detention area 35 Assembly area 4 intermediate beams 5 organic layer sequence 6 Insulation layer 71 first electrode 72 second electrode 81 Thin-film encapsulation 82 Scratch protection layer 83 Cover film 9 external mounting platform E Main emission direction of the organic light-emitting diode L Laser radiation S Separation line

Claims

[1] Method for producing at least one organic light-emitting diode (1) comprising the steps: A) Providing a film (2) as a permanent, flexible substrate for the organic light-emitting diode (1), wherein the film (2) has a film underside (23) and a film topside (25) opposite it, C) Applying an adhesive layer (33) directly and over a large area to the underside of the film (23), wherein the adhesive layer (33) is covered on one side facing away from the film (2) by a protective cover (31), D) Structuring and partially removing the protective cover (31) so that the adhesive layer (33) is exposed in at least one adhesion area (34) and so that the protective cover (31) remains on the adhesive layer (33) in at least one assembly area (35), E) Attaching a temporary intermediate carrier (4) in the adhesive area (34) directly to the adhesive layer (33), so that in the mounting area (35) the protective cover (31) is located between the adhesive layer (33) and the intermediate carrier (4), G) Generating an organic layer sequence (5) for light generation at the top of the film (25), and H) Detaching the bonding area (34) and subsequently removing the intermediate support (4). [2] Method according to the preceding claim, comprising a step B) preceding step C), wherein in step B) the adhesive layer (33) is provided and the adhesive layer (33) is located between the protective cover (31) and a protective layer (32) so that a double-sided adhesive film (3) is formed. [3] Method according to one of the preceding claims, wherein the adhesive layer (33) and the protective cover (31) remain in the finished organic light-emitting diode (1) after step H) and the adhesive layer (33) is provided as a fastening means for the organic light-emitting diode (1) after the subsequent removal of the protective cover (31), so that the organic light-emitting diode (1) can be mounted in a self-adhesive manner. [4] Method according to any one of the preceding claims, in which, between steps E) and G), at least in some places an insulating layer (6) is created on the film (2) in a step F), wherein the insulating layer (6) is based on a polyimide or an acrylate, and wherein the production of the insulating layer (6) includes at least one heating step. [5] Method according to one of the preceding claims, wherein the protective cover (31) is temperature stable such that shrinkage of the protective cover (31) at a temperature of at least 130 °C for a duration of at least 2 h is at most 2 % and the protective cover (31) is not destroyed by a temperature of at least 130 °C for at least 2 h. [6] Method according to one of the preceding claims, wherein, viewed from above, the adhesion area (34) completely surrounds the mounting area (35) outside the organic light-emitting diode (1) in a frame-like manner. [7] Method according to the preceding claim, wherein several of the organic light-emitting diodes (1) are produced which are surrounded by a common adhesive area (34) up to step H), as seen from above, so that the organic light-emitting diodes (1) lie completely on the mounting area (35). [8] Method according to one of the preceding claims, wherein the adhesive layer (33) remains as a continuous, uninterrupted layer until step H), so that the adhesive layer (33) is only cut in step H) in a manner congruent with the at least one organic light-emitting diode (1). [9] Method according to any one of claims 1 to 7, wherein in step D) the adhesive layer (33) is divided together with the protective cover (31) into the assembly area (35) and the adhesion area (34). [10] Method according to any one of the preceding claims, where the protective cover (31) comprises or consists of one or more of the following materials: polyethylene terephthalate, polyethylene, polypropylene, polyimide, polytetrafluoroethylene, polyethylene naphthalate, polyetheretherketone, silicone, polyurethane, epoxy, polyacrylate, polyvinyl chloride, wherein the thickness of the protective cover (31) is between 5 µm and 100 µm inclusive and the adhesive layer (33) has a thickness between 15 µm and 500 µm inclusive, such that the thickness of the adhesive layer (33) exceeds the thickness of the protective cover (31) by at least a factor of 3. [11] Method according to one of the preceding claims, wherein the adhesive layer (33) is mechanically deformable and acts as a buffer such that, after step E), in step G), the top surface of the film (25) is flat with a tolerance of at most 20% of the mean thickness of the protective cover (31). [12] Method according to any one of the preceding claims, where the foil (2) is a metal foil and comprises or consists of one or more of the following materials: Ag, Al, Cr, Cu, Fe, Mo, Ni, V, wherein the film (2) has a thickness between 20 µm and 100 µm inclusive. [13] Method according to one of the preceding claims, wherein the organic layer sequence (5) is produced between two electrodes (71, 72) and one of the electrodes (71) is in direct electrical contact with the film (2), wherein an inorganic thin-film encapsulation (81) and an organic scratch-resistant layer (82) are applied to a side of the organic layer sequence (5) facing away from the film (2) prior to step H), and the scratch-resistant layer (82) is at least a factor of 5 thicker than the thin-film encapsulation (81). [14] Organic light-emitting diode (1) with the following components arranged along a main emission direction (E) of the organic light-emitting diode (1): - a protective cover (31), - a solid adhesive layer (33) for self-adhesive attachment of the organic light-emitting diode (1), - a film (2) as a permanent, flexible substrate, - an insulating layer (6), - an organic layer sequence (5) for light generation, and - at least one encapsulation (81, 82) wherein a material of the adhesive layer (33) has a modulus of elasticity of at most 5 MPa and a thickness of at least 0.1 mm at a temperature of 300 K, such that the adhesive layer (33) serves as a vibration damping layer for the attached organic light-emitting diode (1).

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