AN ORGANIC CONVERSION DEVICE
20170279082 · 2017-09-28
Assignee
Inventors
- Stefan Peter Grabowski (Neuss, DE)
- Herbert LIFKA (Eindhoven, NL)
- Peter Van De Weijer (Heeze, NL)
- Rainald Manfred Gierth (Köln, DE)
- Jens Meyer (Cologne, DE)
- Manfred Stephan Ruske (Kerpen, DE)
- Helga Hummel (Aachen, DE)
Cpc classification
H10K71/00
ELECTRICITY
H10K2102/00
ELECTRICITY
H10K50/8445
ELECTRICITY
Y02P70/50
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
International classification
Abstract
The invention relates to a substrate (2) for manufacturing an organic conversion device for converting electrical energy into light energy or light energy into electrical energy, wherein the substrate comprises a) an encapsulation layer (3) on the substrate, wherein the encapsulation layer includes a first inorganic layer (7), a second inorganic layer (9) and an intermediate organic layer (8), and b) a getter reservoir (6) in contact with the organic layer of the encapsulation layer. Water molecules will therefore not only be transported along the intermediate organic layer, but will also be gathered, especially absorbed, by the getter reservoir, if the encapsulation is damaged. This can slow down a transport of water molecules along a leakage path towards an organic conversion layer of the organic conversion device and hence slow down a possible degradation of the performance of the organic conversion device, if the encapsulation layer is damaged.
Claims
1.-15. (canceled)
16. An organic conversion device for converting electrical energy into light energy or light energy into electrical energy wherein the organic conversion device has a first region and a second region, the second region being arranged laterally relative to the first region, the organic conversion device comprising: a substrate provided with a first encapsulation layer on top of the substrate, the first encapsulation layer including a first inorganic layer on top of the substrate, an intermediate organic layer on top of the first inorganic layer, and a second inorganic layer on top of the intermediate organic layer; a getter reservoir in contact with the intermediate organic layer of the first encapsulation layer provided in the second region; an organic conversion unit on the first encapsulation layer, wherein the organic conversion unit includes a first electrode layer, a second electrode layer, an organic conversion layer in between the first and second electrode layers for converting electrical energy into light energy or light energy into electrical energy and the organic conversion unit is provided in the first region and not in the second region; and a further encapsulation layer encapsulating the organic conversion unit.
17. The organic conversion device as defined in claim 16, wherein the getter reservoir has a volume being larger than the volume of the organic layer.
18. The organic conversion device as defined in claim 16 wherein the getter reservoir comprises getter particles for gathering water molecules.
19. The organic conversion device as defined in claim 18 wherein the getter particles are alkali oxides and/or earth-alkali oxides.
20. The organic conversion device as defined in claim 16 wherein the substrate is a flexible substrate
21. The organic conversion device as defined in claim 20, wherein the flexible substrate is a flexible plastic foil.
22. The organic conversion device as defined in claim 16 wherein the getter reservoir laterally encloses the first electrode layer of the organic conversion unit.
23. The organic conversion device as defined in claim 22, wherein the getter reservoir is arranged as a stripe.
24. The organic conversion device as defined in claim 23 wherein the getter reservoir laterally encloses the first electrode layer of the organic conversion unit on all sides.
25. A method for manufacturing an organic conversion device wherein the method comprises the steps of: providing a substrate with laterally arranged first and second regions; providing a first inorganic layer deposited on top of the substrate and an intermediate organic layer deposited on top of the first inorganic layer; providing a getter reservoir in contact with the intermediate organic layer of the encapsulation layer in the second region and not in the first region; providing a second inorganic layer deposited on top of the intermediate organic layer and the getter reservoir so that the first inorganic layer, the intermediate organic layer and the getter reservoir; and the second inorganic layer are part of a first encapsulation layer; providing a first electrode layer on the encapsulation layer in the first region and not in the second region; providing an organic conversion layer on the first electrode layer and a second electrode layer on the organic conversion layer; providing a third inorganic layer on the second electrode layer in the first region and on the second inorganic layer in the second region; removing the second and third inorganic layers in the second region; and providing a fourth inorganic layer on the getter reservoir.
26. The method of claim 25 wherein the step of removing the second and third inorganic layers is performed by laser ablation.
27. The method of claim 25 wherein the step of providing the getter reservoir is performed by printing.
28. The method of claim 25 wherein the fourth inorganic layer is part of a further encapsulation layer including an intermediate organic layer on the fourth inorganic layer and a fifth inorganic layer on top of the intermediate organic layer.
29. The method of claim 28 wherein several organic conversion units are provided on the first encapsulation layer and several getter reservoirs are provided such that each of these getter reservoirs are in contact with a respective region of the encapsulation layer on which the respective organic conversion unit has been provided, wherein the method further comprises cutting out one or several organic conversion units, each cut section including the respective parts of the substrate, the first encapsulation layer, the respective getter reservoirs in contact with the organic layers of the respective parts of the first encapsulation layer, and the second encapsulation layer.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] In the following drawings:
[0044]
[0045]
[0046]
[0047]
[0048]
[0049]
[0050]
[0051]
[0052]
DETAILED DESCRIPTION OF EMBODIMENTS
[0053]
[0054] The substrate 2 is a flexible plastic substrate and the encapsulation layer 3 is a TFE encapsulation, wherein also the getter reservoir 6 is arranged between the first and second inorganic layers 7, 9. The flexible plastic substrate may comprise, for instance, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyether ether ketone (PEEK) and/or polyimide. However, the substrate may also comprise other materials. In particular, in another embodiment the substrate might be a flexible metal substrate like a flexible copper, aluminum or stainless steel substrate.
[0055] The organic light emitting device 1 further comprises a first electrode layer 10, which is an anode layer in this embodiment, in a first region 18 on the encapsulation layer 3. The anode layer 10 is preferentially an indium tin oxide (ITO) layer. The getter reservoir 6 is arranged laterally relative to the anode layer 10 in a second region 19. The getter reservoir 6 has a height h within a range of 100 μm to 10 mm and a width w within a range of 100 μm to 10 mm. Moreover, the thickness of the organic layer 8 is within a range of 10 μm to 100 μm. The material forming the getter reservoir 6 and the material forming the organic layer 8 of the encapsulation layer 3 may be the same or they may be different.
[0056] Preferred materials for the inorganic layers 7 and 9 are materials with good moisture barrier properties like Si.sub.xN.sub.y, Si.sub.xO.sub.y, Si.sub.xO.sub.yN.sub.z, Al.sub.xO.sub.y, Si.sub.xC.sub.y, Al.sub.xN.sub.y, Zr.sub.xO.sub.y, Hf.sub.xO.sub.y, Ti.sub.xO.sub.y, Zn.sub.xO.sub.y or any combinations thereof. Preferred materials for the organic layer 8 are hydrophobic organic materials that match the mechanical properties of the inorganic layer 7. In an embodiment the organic layer 8 is made of parylene or epoxy. The getter reservoir 6 may be made of the same material as the organic layer 8. However, in an embodiment the getter reservoir 6 may alternatively or additionally comprise getter particles like alkali oxide or earth-alkali oxide particles. In particular, the getter reservoir 6 may comprise the getter particles in a matrix formed by the organic material used for the organic layer 8 or formed by another organic material.
[0057] On the anode layer 10 an organic light emission layer 11 and a second electrode layer 12 being, in this embodiment, a cathode layer, are arranged, in order to form a light emission unit 4. The anode layer 10 is preferentially an ITO layer and the organic light emission layer 11 may comprise several sublayers like a hole injection layer, a hole transport layer, an emission layer which might be a double emission layer, an electron transport layer and an electron injection layer. In an embodiment the organic light emission layer 11 includes a) a 5 nm MoO.sub.3 layer hole injection layer, b) a 40 nm 4,4′-Bis(N-carbazolyl)-1,1′-biphenyl (CBP) hole transport layer, c) a double emission layer comprised of 7.5 nm CBP and 7.5 nm 1,3,5-tris-phenyl-2-benzimidazolyl-benzene (TPBi) both doped with, for instance, a green phosphorescent emitter material like fac-tris-2-phenylpyridine iridium (Irppy3), wherein the dopant level might be 10 percent by weight, d) a 60 nm TPBi electron transport layer and e) a 1 nm LiF electron injection layer. In other embodiments the organic light emission layer 11 may of course comprise another sequence of sublayers. The second electrode layer 12 is preferentially a metal layer like an aluminum layer having a thickness of, for instance, 100 nm. Also the second electrode layer can of course comprise other materials like silver or ITO.
[0058] The light emission unit 4 is encapsulated by a further encapsulation layer 5 comprising a third inorganic layer 13, an organic layer 14 and a fourth inorganic layer 15. The third and fourth inorganic layers 13, 15 are preferentially formed of the same materials as the first and second inorganic layers 7, 9. However, they can of course also be made of different materials. Preferred materials for the inorganic layers 13 and 15 are materials with good moisture barrier properties like Si.sub.xN.sub.y, Si.sub.xO.sub.y, Si.sub.xO.sub.yN.sub.z, Al.sub.xO.sub.y, Si.sub.xC.sub.y, Al.sub.xN.sub.y, Zr.sub.xO.sub.y, Hf.sub.xO.sub.y, Ti.sub.xO.sub.y, Zn.sub.xO.sub.y or any combinations thereof. Also the organic layers 8 and 14 are preferentially made of the same material. However, they can also be made of different materials. Preferred materials for the organic layer 14 are hydrophobic organic materials that match the mechanical properties of the inorganic layer 13. In an embodiment the organic layer 14 comprises parylene or epoxy.
[0059] The anode layer 10 and the cathode layer 12 of the light emission unit 4 are electrically connected to a voltage source via electrical connections in a known way (not shown in
[0060] It should be noted that
[0061] In the following a manufacturing method for manufacturing an organic conversion device will be exemplarily described with reference to a flowchart shown in
[0062] In the following steps an encapsulation and getter reservoir providing unit 31 provides a) an encapsulation layer 3 with a first inorganic layer 7, a second inorganic layer 9 and an organic layer 8 in between the first and second inorganic layers 7, 9 on the substrate 2 and b) a getter reservoir 6 in contact with the organic layer 8.
[0063] In step 102 the first inorganic layer 7, which is preferentially a silicon nitride layer, is deposited on the substrate 2. The resulting intermediate product is schematically and exemplarily illustrated in
[0064] In step 103 the organic layer 8 is provided on the first inorganic layer 7 and the getter reservoir 6 is provided such that the getter reservoir 6 and the organic layer 8 are in contact. In particular, the organic layer 8 may be printed on top of the first inorganic layer 7. The getter material forming the getter reservoir 6 may also be printed or may be evaporated. The intermediate product after having provided the organic layer 8 and the getter reservoir 6 is schematically and exemplarily shown in
[0065] In step 104 the second inorganic layer 9 is provided on the getter reservoir 6 and on the organic layer 8. In particular, a silicon nitride layer preferentially forming the second inorganic layer 9 is deposited on top of the getter reservoir 6 and the organic layer 8, wherein the resulting intermediate product is schematically and exemplarily shown in
[0066] Steps 101 to 104 can be regarded as being steps of a method for providing a substrate with an encapsulation layer. Correspondingly, the substrate providing unit 30 and the encapsulation and getter reservoir providing unit 31 can be regarded as being units of an apparatus for providing a substrate with an encapsulation layer.
[0067] The following steps are performed by a conversion unit providing unit being, in this embodiment, a light emission unit providing unit 33 for providing the light emission unit 4 on the encapsulation layer 3. In step 105 the first electrode layer 10, which is preferentially an anode layer, is deposited on the second inorganic layer 9. The resulting intermediate product is schematically and exemplarily shown in
[0068] Although the manufacturing apparatus 35 has been described as comprising certain units for carrying out the steps of the manufacturing method, in other embodiments more or less units may be provided for carrying out these steps. Moreover, these steps may be performed in another order or other steps may be carried out, in order to provide an organic light emitting device comprising a substrate with an encapsulation layer, which comprises a first inorganic layer, a second inorganic layer and an organic layer in between the first and second inorganic layers, and a getter reservoir in contact with the organic layer of the encapsulation layer. Such an alternative manufacturing method will in the following be described with reference to a flowchart shown in
[0069] In step 201 a substrate 2 is provided, which is preferentially a flexible plastic foil. In step 202 the first inorganic layer 7 is deposited on the substrate 2, in step 203 the organic layer 8 is deposited on the first inorganic layer 7 and in step 204 the second inorganic layer is deposited on the organic layer 8. In step 204 the first electrode layer 10, which is preferentially a transparent anode layer, is provided in a first region 18 and not in a second region 19 on the second inorganic layer 9. In step 205 the organic light emission layer 11, i.e. the different layers of this organic light emission layer 11, are deposited on the first electrode layer 10 and in step 206 the second electrode layer 12 is provided on the organic light emission layer 11. The resulting intermediate product is schematically and exemplarily illustrated in
[0070] As schematically and exemplarily illustrated in
[0071] In step 209 an organic material 14 is deposited on top of the third inorganic layer 13 covering the second electrode layer 12, for instance, by printing and the getter reservoir 6 is provided, especially printed, preferably at the same time, in the second region 19 on top of the organic layer 8, such that the resulting getter reservoir 6 is in contact with the organic layer 8 as schematically and exemplarily illustrated in
[0072] In step 211 the third and fourth inorganic layers 13, 15, which are preferentially silicon nitride layers, are opened above a part of the first electrode layer 10, which should be electrically connected, as schematically and exemplarily illustrated in
[0073] Since steps 201 to 210 lead to an encapsulation layer on the substrate, wherein the encapsulation layer comprises two inorganic layers and an intermediate organic layer in contact with a getter reservoir, these steps can be regarded as being steps of a method for providing a substrate with an encapsulation layer.
[0074] The production of organic light emitting devices may include cutting them out of large area plastic substrates or out of a roll that is being used in a roll-to-roll process, wherein this cutting out procedure may lead to a damage of the encapsulation of the substrate and a leakage path may be opened up. In particular, when cutting out organic light emitting devices on a plastic foil, the TFE on the substrate side may be damaged such that from the sides moisture may enter the organic layer of the TFE. Water molecules may then be transported quickly over the whole area. If the water molecules find a pinhole in the respective second inorganic layer, they can access the light emission unit and create a black spot that will grow with time. The above described apparatus and method for providing a substrate with an encapsulation layer are therefore adapted such that the transport of moisture and thus the formation of black spots is significantly delayed.
[0075] For instance, on a same substrate one or several light emission units may be produced, wherein, if several light emission units are produced on a same substrate, one or several light emission units may be cut out. This cutting out is preferentially performed outside a respective getter reservoir such that an encapsulation layer on a substrate below a respective light emission unit is still in contact with a getter reservoir, after the light emission unit has been cut out. This will in the following be illustrated with reference to
[0076]
[0077] Without the getter reservoir 6 a situation as illustrated in
[0078] The above described apparatus and method for providing a substrate with an encapsulation layer are therefore preferentially used to provide a substrate with an encapsulation layer, which allows for a production of cuttable organic light emitting devices that are cut out of a larger plastic substrate and which allow for a reduction of side leakage in organic light emitting devices that have been manufactured in a roll-to-roll process. These effects rely on the reservoir with material that getters moisture. This reservoir is connected to the organic layer in the encapsulation layer being preferentially a TFE. It can be integrated into the substrate, which is preferentially a foil, by the substrate manufacturer, i.e. the substrate manufacturer can already provide a substrate with the encapsulation layer and the getter reservoir in contact with the organic layer of the encapsulation layer, or the reservoir can be applied later by an organic light emitting device manufacturer such that it is in contact with the organic layer of the encapsulation layer on the substrate.
[0079] It would be preferred if at the edge of the encapsulation layer on the substrate the organic material is buried between the two inorganic layers, in order to avoid contact with air as shown, for instance, on the left side of
[0080] Preferentially, a huge getter reservoir, which is in contact with the organic barrier material of the bottom encapsulation layer which is preferentially a bottom TFE, sits next to the respective light emission unit. The getter capacity of the getter reservoir is preferentially huge compared to the getter capacity of the organic barrier material that might be along a leakage path to a pinhole in the second inorganic layer, i.e. In the inorganic layer of the encapsulation layer towards the light emission unit. The organic layer of the encapsulation may have a thickness in the several 10 μm range. The getter reservoir can have a height of several millimeters and its width can range from several 100 μm to several millimeters, depending on the available space. The getter reservoir can be made such that it encloses the respective light emission unit from all sides. When moisture enters from the side, it will propagate towards the respective light emission unit until it finds a pinhole in the second inorganic layer 9, where it may create a black spot. However, since the getter reservoir is present, the overall volume of getter material that the water molecules see on their way to the pinhole is much larger than in the case where a getter reservoir is not present.
[0081] When moisture accesses the organic layer of the encapsulation layer from an opening at the side, the moisture will be transported through the layer. However, when the moisture reaches the getter reservoir, it finds a large amount of getter material. Since the moisture transport is diffusion driven and due to the large amount of getter material, i.e. since it takes the water molecules a long time to saturate, for instance, all getter particles, there will be a diffusion gradient for the water molecules into the getter reservoir for a long time. This will direct the moisture away from the respective light emission unit into the respective getter reservoir. The organic layer serves as a quick diffusion path for the water molecules towards the getter material in the getter reservoir. The formation of black spots will therefore be delayed, especially for cut out organic light emitting devices having a damaged encapsulation layer.
[0082] The above described methods can include other and/or further steps for providing a substrate with an encapsulation layer such that a getter reservoir is in contact with the organic layer of the encapsulation layer and for manufacturing organic light emitting devices comprising this substrate. In particular, these methods can be parts of a longer process chain, wherein, for instance, more process steps can take place before or after the above described steps. For instance, an additional edge sealing step can be performed, in order to seal a leakage path at the sides of the respective organic light emitting device. A sealing material having a sealing property against moisture may be deposited on the sides of the respective organic light emitting device for providing the edge sealing. This edge sealing in combination with the getter reservoir in contact with the organic layer of the encapsulation layer on the substrate can lead to a further delayed formation of black spots. Preferred materials for the edge sealing are materials with good barrier properties like silicon nitride, aluminum oxide or metals.
[0083] The substrate with the getter reservoir in contact with the organic layer of the encapsulation layer on the substrate is preferentially used for organic light emitting devices on flexible substrates, wherein a leakage path may be generated by cutting the substrate to a smaller size. Thus, the substrate with a getter reservoir in contact with the organic layer of the encapsulation layer may be used for, for instance, cuttable organic light emitting devices, which can be cut to a desired size after processing, and for organic light emitting devices made in a roll-to-roll process.
[0084] Although in above described embodiments the substrate with the encapsulation layer and the getter reservoir is used for manufacturing an organic light emitting device, in other embodiments the substrate with the encapsulation layer and the getter reservoir may be used for manufacturing another organic conversion device like an organic photovoltaic device. The substrate with the encapsulation layer and the getter reservoir may also be used for manufacturing a hybrid organic-inorganic light emitting device, especially a hybrid organic-inorganic perovskite light emitting device.
[0085] Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.
[0086] In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality.
[0087] A single unit or device may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.
[0088] The control of the apparatus for providing a substrate with an encapsulation layer in accordance with the method for providing a substrate with an encapsulation layer and/or the control of the manufacturing apparatus for manufacturing an organic conversion device in accordance with the manufacturing method for manufacturing an organic conversion device can be implemented as program code means of a computer program and/or as dedicated hardware. However, in an embodiment the apparatuses may also be manually controlled or semi-automatically controlled.
[0089] A computer program may be stored/distributed on a suitable medium, such as an optical storage medium or a solid-state medium, supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems.
[0090] Any reference signs in the claims should not be construed as limiting the scope.