Method for producing an electronic component and electronic component

Abstract

Method for producing an electronic component with barrier layers for encapsulating the component, comprising the steps: - providing a substrate (1) with at least one functional layer (22), - applying at least a first barrier layer (3) on the functional layer (22) by means of plasmaless atomic layer deposition (PLALD) and - applying at least one second barrier layer (4) to the functional layer (22) by means of plasma-enhanced chemical vapor deposition (PECVD), wherein a layer sequence of at least two layers (41, 42) with different materials is applied as the second barrier layer (4), and - applying a protective layer (5) on the first and second barrier layer (3, 4), wherein the protective layer (5) is made of a plastic and has a thickness of greater than or equal to 10 µm.

Description

A method for producing an electronic component and an electronic component are specified.For a permanent operation of electronic components such as inorganic light emitting diodes (LEDs) or organic light emitting diodes (OLEDs), it is often necessary to protect them from moisture. In particular, the devices may need to be subjected to extensive life tests to ensure that they can retain their functionality for years in common use.Organic electroluminescent components are described in the publications US 2006 / 0109397 A1 and WO 2007 / 015779 A2.An object of at least one embodiment is therefore to specify a method for producing an electronic component having an encapsulation. Furthermore, it is an object of at least one embodiment to specify an electronic component having an encapsulation.These objects are achieved according to the invention by the method and the subject matter of the independent claims. Advantageous embodiments and developments of the method and the subject matter are characterized in the dependent claims and are furthermore evident from the following description and the drawings.A method for producing an electronic component having barrier layers for encapsulating the component comprises, in particular, the steps:providing a substrate having at least one functional layer,applying at least one first barrier layer on the functional layer by means of plasmaless atomic layer deposition (PLALD), andapplying at least one second barrier layer on the functional layer by means of plasma-enhanced chemical vapor deposition (PECVD).The fact that a first layer or a first element is arranged or applied "on" or "over" a second layer or a second element or else "between" two further layers or elements can mean here and below that the first layer or the first element is arranged directly in direct mechanical and / or electrical contact on the second layer or the second element or with respect to the two further layers or elements. Furthermore, an indirect contact may also be designated, in which further layers and / or elements are arranged between the first layer or the first element and the second layer or the second element or the two further layers or elements.A chemical vapor deposition (CVD) may refer to a method in which at least two gaseous starting compounds react with the at least one functional layer on at least one surface of the provided substrate to form a solid reaction product. In this case, the at least two gaseous starting compounds can be fed simultaneously to a volume in which the substrate is provided. Furthermore, it may be necessary for the at least one surface of the provided substrate with the at least one functional layer to be heated to a temperature above room temperature.A plasma enhanced chemical vapor deposition (PECVD) may refer to a CVD method in which a plasma is generated in the volume, as a result of which the at least two gaseous starting compounds supplied to the volume can be excited in the plasma. As a result, it may be possible for the temperature to which the at least one surface has to be heated to be lowered in comparison with a plasmaless CVD method. This may be advantageous in particular since the at least one functional layer may be irreversibly damaged at a temperature above a maximum temperature. The maximum temperature can be, for example, about 120° C., so that the temperature at which the second barrier layer is applied can be less than 120° C., and preferably less than or equal to 80° C.An atomic layer deposition (ALD) may refer to a method in which, in comparison with a CVD method, a first of the at least two gaseous starting compounds is first supplied to the volume in which the substrate is provided and can adsorb on the at least one surface. After preferably complete or nearly complete coverage of the at least one surface with the first starting compound, the part of the first starting compound which is still present in gaseous form and / or not adsorbed on the surface can be removed again from the volume and the second of the at least two starting compounds can be supplied. The second starting compound may react with the first starting compound adsorbed on the at least one surface to form a solid layer. As in a CVD method, it may be advantageous if the at least one surface is heated to a temperature above room temperature. Thereby, the reaction for forming a solid layer can be thermally initiated. The surface temperature, which can also be, for example, the substrate temperature, i.e. the temperature of the substrate, can depend on the starting materials, i.e. the first and second starting compounds.A plasma-less atomic layer deposition (PLALD) can thereby denote an ALD method for which no plasma is generated as described below, but in which, in order to form a solid layer, i.e. for example the first barrier layer, the reaction of the abovementioned starting compounds is initiated only via the temperature of the surface to be coated.The temperature of the at least one surface and / or of the substrate can be, for example, greater than or equal to 60° C. and less than or equal to 120° C. in a PLALD method.Plasma enhanced atomic layer deposition (PEALD) may refer to an ALD method in which the second starting compound is supplied while generating a plasma, whereby, as in PECVD methods, it may be possible for the second starting compound to be excited. As a result, in comparison with a plasmaless ALD method, the temperature to which the at least one surface is heated can be reduced and the reaction between starting compounds can nevertheless be initiated by the plasma generation. The first barrier layer can be applied here, for example, at a temperature of less than 120° C. and preferably less than or equal to 80° C. To create another solid layer, the steps of feeding the first output link and thereafter feeding the second output link may be repeated.In particular, a PEALD method may be advantageous if initiation of the reaction between the starting compounds requires a surface temperature at which, for example, the at least one functional layer and / or the substrate would be damaged.The encapsulation producible within the scope of the method described here may have a lower permeability for moisture and / or oxygen compared to known encapsulations with barrier layers, all produced by CVD methods. In encapsulations with barrier layers, all of which are produced by CVD methods, channels, pores and / or grain boundaries may occur, which may lead to leaks in the conventional encapsulations. Such leaks can be promoted in particular by the fact that, in the case of electronic components, the maximum temperature at which barrier layers can be applied, as mentioned above, must not exceed about 120° C. and preferably about 80° C. As a result, conventional encapsulations with CVD-applied barrier layers require very complex and thus cost-intensive multilayer systems which can prevent economical production of electronic components with an encapsulation.These disadvantages of conventional encapsulations can be avoided by the method described here. By a PLALD method or by a PEALD method for applying the first barrier layer, the first barrier layer can be produced with a higher density compared to a barrier layer applied by a CVD or PECVD method and the formation and / or continuation of channels and / or pores can be reduced or prevented in this case. Thus, in comparison with a layer for the first barrier layer produced by means of a CVD method, a higher tightness with respect to moisture and / or oxygen can also be achieved. In this case, it may be possible that the number of barrier layers and / or their thickness may be reduced compared to barrier layers of encapsulations produced using conventional CVD methods. As a result, a thin encapsulation with simultaneously high intrinsic tightness can be produced on small surfaces as well as over a large surface area and the diffusion of moisture and / or oxygen through grain boundaries, channels and / or pores can be reduced or prevented. Furthermore, the encapsulation described here with the first and second barrier layers can also have a high degree of tightness in edge regions of the encapsulation, such that diffusion of moisture and / or oxygen through interfaces between the encapsulation and the provided substrate with the at least one functional layer can be reduced or prevented.In comparison with further known encapsulations by means of a cover glass, in which a getter material is additionally introduced into a cavity, the encapsulation described here with the first and second barrier layers enables more cost-effective production and a smaller thickness of the encapsulation. Furthermore, it may be possible with the method described here to produce an electronic component with a transparent encapsulation, which is not possible in the case of encapsulation by means of cover glass and getter material.The method steps of applying the first barrier layer by means of PLALD or also by means of PEALD and applying the second barrier layer by means of PECVD can be carried out directly one after the other in the same volume, for example in a conventional coating plant. For this purpose, the coating installation can have, for example, a vacuum chamber with gas inlets for the starting compounds of the PLALD method or of the PEALD method, in which, in the case of the PLALD method, a heater for the substrate is furthermore provided. Furthermore, a heater for the substrate can also be provided for a PEALD method and / or for the PECVD method.The first barrier layer can be applied by means of the PLALD method or by means of the PEALD method, for example, with a thickness of greater than or equal to 10 nm and less than or equal to 30 nm. This can mean that the first barrier layer can be produced with greater than or equal to 10 monolayers and less than or equal to 50 monolayers by means of the PLALD method or by means of the PEALD method. Due to the high density and quality of the first barrier layer, such a thickness may be sufficient to ensure effective protection against moisture and / or oxygen for the underlying at least one functional layer. Although the PLALD method or the PEALD method may have a lower growth rate compared to the PECVD method, a short process time and thus a high economic efficiency of the method described here may be ensured due to the small thickness of the first barrier layer.Due to the high tightness of the first barrier layer, the requirements for the second barrier layer with regard to tightness can be set lower than in a conventional encapsulation with barrier layers, all of which are applied by CVD methods. In particular, the second barrier layer may be deposited at a higher growth rate than the first barrier layer and may have a thickness of greater than or equal to 1 nm and less than or equal to 1000 nm after deposition. In particular, the first barrier layer can be applied with a thickness of greater than or equal to 10 nm, preferably greater than or equal to 20 nm and particularly preferably greater than or equal to 100 nm.The method can have a further method step in which a protective layer is applied to the first and second barrier layers. In this case, the protective layer can be applied directly on the first or second barrier layer and thus be in direct contact with the first or second barrier layer after the application. In particular, the protective layer may allow a mechanical protection of the underlying first and second barrier layers. For this purpose, the protective layer can be applied with a thickness of greater than or equal to 1 μm and less than or equal to 100 μm. In particular, the protective layer can be applied with a thickness of greater than or equal to 5 μm and preferably with a thickness of greater than or equal to 10 μm.The protective layer may comprise plastics such as siloxanes, epoxides, acrylates such as methyl methacrylates, imides, carbonates, olefins, styrenes, urethanes or derivatives thereof in the form of monomers, oligomers or polymers and also mixtures, copolymers or compounds thereof. For example, the protective layer may comprise or be an epoxy resin, polymethyl methacrylate (PMMA), polystyrene, polycarbonate, polyacrylate, polyurethane or a silicone resin such as polysiloxane or mixtures thereof. The protective layer can be transparent, for example.The protective layer can furthermore have a spray paint or be designed as a spray paint which comprises at least one of the aforementioned materials and which can be applied, for example, by means of a continuous spray paint system. The spray coating can furthermore be a UV-curable and / or a binder- or solvent-containing spray coating.The electronic component that can be produced by the method described here can be designed as a radiation-emitting and / or radiation-receiving component and in this case as an organic or inorganic electronic component, for example as an inorganic light-emitting diode (LED), organic light-emitting diode (OLED), inorganic photodiode (PD), organic photodiode (OPD), inorganic solar cell (SC), organic solar cell (OSC), inorganic transistor, in particular inorganic thin-film transistor (TFT), organic transistor, in particular organic thin-film transistor (OTFT), or as an integrated circuit (IC). Furthermore, the electronic component that can be produced by the method described here can have a plurality or combination of the mentioned elements or can be formed in this way.After production, the electronic component can furthermore have a functional layer sequence having at least one first and one second electrode, between which the at least one functional layer comprising one or more inorganic and / or organic functional layers are arranged. In particular, the functional layer sequence can be arranged on a substrate.If the component has, for example, an LED, an OLED, a PD, an OPD, an SC and / or an OSC, the functional layer sequence can have an active region which is suitable for generating or detecting electromagnetic radiation during operation of the electronic component.In a particularly preferred embodiment, in the method described here, the electronic component is produced as an organic electronic component comprising an organic radiation-emitting component having a radiation-emitting layer sequence. The radiation-emitting layer sequence can comprise the functional layer formed as an organic functional layer. In particular, the electronic component can comprise an organic, radiation-emitting diode (OLED) or be embodied as such. For this purpose, the electronic component can have an active region which is suitable for emitting electromagnetic radiation by recombination of electrons and holes during operation of the electronic component.An organic radiation-emitting layer sequence or an OLED can have, for example, a first electrode on the substrate. The at least one organic functional layer or a plurality of functional layers made of organic materials can be applied over the first electrode. The at least one organic functional layer or the plurality of functional layers may have, for example, electron transport layers, electroluminescent layers and / or hole transport layers or be embodied as such. A second electrode may be applied over the organic functional layer or the plurality of organic functional layers.For example, the substrate may comprise glass, quartz, plastic films, metal, metal foils, silicon wafers or another suitable substrate material. If the OLED is embodied as a so-called "bottom emitter", that is to say the radiation generated in the active region is emitted through the substrate, the substrate can have transparency for at least some of the first radiation.In the bottom-emitter configuration, the first electrode can advantageously also have transparency for at least some of the primary radiation. A transparent first electrode, which can be designed as an anode and thus serves as a hole-injecting material, can comprise a transparent conductive oxide or consist of a transparent conductive oxide, for example. Transparent conductive oxides ("TCO" for short) are transparent conductive materials, generally metal oxides, such as, for example, zinc oxide, tin oxide, cadmium oxide, titanium oxide, indium oxide or indium tin oxide (ITO). Besides binary metal oxygen compounds, such as ZnO, SnO 2 or In 2 O 3 ternary metal oxygen compounds, such as Zn 2 SnO 4, CdSnO 3, ZnSnO 3, MgIn 2 O 4, GaInO 3, also belong, Zn 2 In 2 O 5 or In 4 Sn 3 O 12 or mixtures of different transparent conductive oxides to form the group of TCOs. Furthermore, the TCOs do not necessarily correspond to a stoichiometric composition and can also be p- or n-doped.The organic functional layer or plurality of functional layers may include organic polymers, organic oligomers, organic monomers, organic small, non-polymeric molecules (small molecules), or combinations thereof. In particular, it may be advantageous if the organic radiation-emitting layer sequence has a functional layer which is embodied as a hole transport layer in order to enable effective hole injection into an electroluminescent layer or an electroluminescent region. Materials which may prove advantageous for a hole transport layer are, for example, tertiary amines, carbazole derivatives, conductive polyaniline or polyethylenedioxythiophene. Furthermore, it can be advantageous if a functional layer is designed as an electroluminescent layer. Suitable materials for this purpose are materials which have radiation emission on the basis of fluorescence or phosphorescence, for example polyfluorene, polythiophene or polyphenylene or derivatives, compounds, mixtures or copolymers thereof. Depending on the materials in the functional layers, the generated first radiation can have individual wavelengths or ranges or combinations thereof from the ultraviolet to red spectral range.The second electrode can be designed as a cathode and thus serve as an electron-injecting material. In particular, aluminum, barium, indium, silver, gold, magnesium, calcium or lithium and compounds, combinations and alloys thereof may prove to be advantageous as cathode material, among others. Alternatively or additionally, the second electrode can also have one of the above-mentioned TCOs. Additionally or alternatively, the second electrode can also be embodied as transparent and / or the first electrode can be embodied as cathode and the second electrode as anode. This means in particular that the OLED can also be embodied as a "top emitter".The first and / or the second electrode can each be formed over a large surface area. In the case of an OLED, this makes it possible to achieve large-area emission of the electromagnetic radiation generated in the active region."Large-area" can mean here that the electronic component has an area of greater than or equal to a few square millimeters, preferably greater than or equal to a square centimeter and particularly preferably greater than or equal to a square centimeter. Alternatively or additionally, the first and / or the second electrode can be structured at least in partial regions. This can allow structured emission of the electromagnetic radiation generated in the active region, for example in the form of pixels or pictograms.Alternatively or additionally, the organic electronic component can be formed in such a way that the substrate with the at least one functional layer formed as an organic functional layer comprises a photodetector and / or a transistor or is formed as such.Furthermore, the electronic component can be produced as an organic electronic component comprising an organic solar cell or photodiode. The electronic component can have a functional layer formed as an organic functional layer, which has features of the functional layer mentioned in connection with the OLED. Furthermore, the electronic component comprising a solar cell or photodiode can have electrodes with features of the electrodes described above in connection with the OLED.Furthermore, the electronic component can be designed as an inorganic electronic component which comprises, for example, an LED, PD, SC and / or a TFT. In this case, the at least one functional layer can have an epitaxial layer sequence, that is to say an epitaxially grown semiconductor layer sequence, or can be embodied as such. In particular, the semiconductor layer sequence can have, for example, a III-V compound semiconductor based on InGaAlN, InGaAlP and / or AlGAs and / or a II-VI compound semiconductor having one or more of the elements Be, Mg, Ca and Sr and one or more of the elements O, S and Se. For example, the II-VI compound semiconductor materials include ZnO, ZnMgO, CdS, ZnMnS and MgBeO. Furthermore, the inorganic electronic component can have electrodes with features of the electrodes described above in connection with the OLED.The first barrier layer can be applied to the at least one functional layer before the second barrier layer. As a result, a high-density surface uniformly covering the functional layer can be provided by the first barrier layer, on which surface the second barrier layer is then applied. The excellent surface properties of the first barrier layer can reduce the tendency of the second barrier layer to form diffusion channels, grain boundaries and / or pores.In particular, the first barrier layer can be applied directly to the above-mentioned second electrode or to the radiation-emitting or radiation-receiving layer sequence. By applying by means of the PLALD method or by means of the PEALD method, the first barrier layer can be applied uniformly thick and completely covering the substrate with the at least one functional layer or the functional layer sequence. As a result, no planarization layer is required between the functional layer or the functional layer sequence and the encapsulation.Alternatively, the second barrier layer can be applied before the application of the first barrier layer. This can also be advantageous in particular because grain boundaries, channels and / or pores can be produced during the application of the second barrier layer, which can be sealed by the high-density second barrier layer.The first barrier layer and the second barrier layer can each comprise a material which is suitable for protecting the at least one functional layer from damaging influences of the environment, that is to say for example from oxygen and / or moisture. For example, an oxide, a nitride or an oxynitride can be applied as the first barrier layer and / or as the second barrier layer in crystalline or glassy form. For example, the oxide, nitride or oxynitride can furthermore comprise aluminum, silicon, tin, zinc, titanium, zirconium, tantalum, niobium or hafnium. The first and / or the second barrier layer can have dielectric or else electrically conductive properties and can have, for example, silicon oxide (SiO x), such as, for example, SiO 2, silicon nitride (Si x N y), such as, for example, Si 2 N 3, silicon oxynitride (SiO x N y), aluminum oxide, for example Al 2 O 3, aluminum nitride, tin oxide, indium tin oxide, zinc oxide or aluminum zinc oxide.To produce the first barrier layer, in the PEALD process described above, an organometallic or a semimetal-organic compound, for example, can be fed as first starting compound. As a second starting compound, in which the plasma is then generated, an oxygen- and / or nitrogen-containing compound can be supplied. If the first barrier layer comprises, purely by way of example, approximately Al 2 O 3, then, for example, trimethylaluminum can be supplied as the first starting compound and 2 O can be supplied as the second starting compound.Furthermore, in order to produce the first barrier layer in the PLALD process described above, an organometallic or a semimetal-organic compound, for example, can be added as first starting compound. Water, for example, can be supplied as the second starting compound. In particular, water can be supplied as the second starting compound in combination with trimethylaluminum as the first starting compound. As a result, a first barrier layer comprising Al 2 O 3 can be produced. Alternatively, water can also be supplied as the first starting compound and an organometallic or a semimetal-organic compound, for example trimethylaluminum, can be supplied as the second starting compound, since no plasma has to be generated in the PLALD.The second barrier layer can furthermore have a layer sequence composed of at least two layers with different materials. This can mean that the layer sequence with at least two different layers is applied as the second barrier layer. For example, the layer sequence can have a layer with an oxide and a layer with a nitride. The layer sequence can also have a plurality of first layers with a first material, for example a nitride, and / or a plurality of second layers with a second material, for example an oxide, which are applied alternately to one another. If the first, nitride-containing layer is denoted by "N" and the second, oxide-containing layer is denoted by "O", the layer sequence can be formed, for example, in a sequence NON or NONON or else ONON or ONON.Furthermore, a further first barrier layer and / or a further second barrier layer can be applied to the at least one first barrier layer and / or to the at least one second barrier layer. Thus, for example, a plurality of first barrier layers and / or a plurality of second barrier layers can be applied to the substrate having the at least one organic functional layer. The first barrier layers and the second barrier layers can preferably be applied alternately to one another.The further first barrier layer or the further second barrier layer can have at least one or more features which are described in connection with the at least one first or the at least one second barrier layer. In particular, each further first barrier layer can be applied by means of a PLALD method or by means of a PEALD method, while each further second barrier layer can be applied by means of a PECVD method. Depending on the combination to be produced of, for example, different first barrier layers, a first barrier layer can also be applied by means of a PLALD method, for example, and a further first barrier layer can be applied by means of a PEALD method, for example.According to a further embodiment, an electronic component is produced by means of the method described here. The electronic component can in particular have a substrate with at least one functional layer and, above it, at least one first barrier layer and at least one second barrier layer. The at least one first barrier layer and the at least one second barrier layer can each have one or more of the features described above. The electronic component can be distinguished by a small thickness with simultaneously high tightness of the encapsulation, which can be produced with high economic efficiency.Further advantages and advantageous embodiments and developments of the invention result from the embodiments described below in connection with FIGS. 1A to 5.The following are shown: FIGS. 1A to 1C are schematic representations of a method according to an exemplary embodiment, FIG. 2 shows a schematic illustration of an organic electronic component which can be produced by means of a method according to a further exemplary embodiment, and FIGS. 3 to 5 are schematic representations of sections of electronic components that can be produced by means of methods according to further exemplary embodiments.In the exemplary embodiments and figures, identical or identically acting components can each be provided with the same reference numerals. The elements shown and their size relationships to one another are fundamentally not to be regarded as being to scale, rather individual elements, such as layers, components, components and regions, can be shown with exaggerated thickness or large dimensions for better illustration and / or for better understanding.Exemplary embodiments for producing electronic components and exemplary embodiments of electronic components which are embodied as organic electronic components comprising an OLED are shown in the following figures purely by way of example. It is expressly pointed out that the methods, components and features thereof described below also apply to the other electronic components described in the general part.FIGS. 1A to 1C show a method for producing an organic electronic component according to one exemplary embodiment.In a first method step according to FIG. 1A, a substrate 1 having at least one organic functional layer 22 is provided. The organic functional layer 22 is part of an organic layer sequence 2 and is embedded between a first electrode 21 and a second electrode 23. The substrate 1 with the organic layer sequence 2 is formed here as an organic light-emitting diode (OLED) and can have further functional layers as described above in the general part (not shown). The electrical contacting of the first and second electrodes 21, 23 takes place via conductor tracks, which are not shown for the sake of clarity.In the exemplary embodiment shown, the substrate 1 with the organic layer sequence 2 is embodied as a bottom emitter and has a transparent substrate 1 made of glass and a transparent first electrode 21 made of ITO, which is embodied as an anode. The second electrode 23 is reflective and designed as a cathode and comprises aluminum.In a further method step according to FIG. 1B, a first barrier layer 3 made of Al 2 O 3 is applied by means of a PLALD method on the organic functional layer 22 and in particular on the layer sequence 2. For this purpose, the substrate 1 with the organic layer sequence 2 is heated to a temperature of approximately 80° C. in a coating system and, in a first substep, is exposed to trimethylaluminum as a first starting compound, such that the trimethylaluminum can adsorb on the surface formed by the layer sequence 2 and the substrate 1. In order to avoid adsorption of the first starting compound, for example, on a contact region of the substrate 1 for later electrical contacting of the organic electronic component, it is possible, for example, to use a mask layer covering the contact region, which mask layer can be removed again after the application of the first barrier layer. After removal of the nonadsorbed portion of the trimethylaluminum, the substrate 1 with the layer stack 2 is exposed to water (H 2 O) as second starting compound in a second substep of the PLALD method. The water can react with the trimethylaluminum adsorbed on the substrate 1 and the layer sequence 2 to form an Al 2 O 3- layer having a thickness in the range from less than 1 nm to several nanometers, which is preferably formed as a monolayer, however. The first and the second substep of the PLALD method are repeated immediately until a first barrier layer 3 10 to 30 nm thick is produced.Alternatively, water can also be supplied as the first starting compound, so that the water can adsorb on the surface formed by the layer sequence 2 and the substrate 1. Thereafter, trimethylaluminum may be supplied as a second starting compound and reacted with the adsorbed water layer to form an Al 2 O 3- layer.Furthermore, it is also possible to supply sufficient of the second starting compound that the material of the second starting compound can in turn adsorb on the Al 2 O 3- layer formed by reaction and react with the first starting compound supplied thereafter to form a further single- or multi-layered Al 2 O 3- layer.Alternatively to the PLALD method, in the further method step according to FIG. 1B, a first barrier layer 3 made of Al 2 O 3 can be applied by means of a PEALD method on the organic functional layer 22 and in particular on the layer sequence 2. For this purpose, the substrate 1 with the organic layer sequence 2 is heated in a coating system to a temperature of less than 100° C. and preferably less than 80° C. and, in a first substep, is exposed to trimethylaluminum as a first starting compound, such that the trimethylaluminum can adsorb on the surface formed by the layer sequence 2 and the substrate 1. In order to avoid adsorption of the first starting compound, for example, on a contact region of the substrate 1 for later electrical contacting of the organic electronic component, it is possible, for example, to use a mask layer covering the contact region, which mask layer can be removed again after the application of the first barrier layer. After removal of the nonadsorbed portion of the trimethylaluminum, the substrate 1 with the layer stack 2 is exposed to a plasma with N 2 O as the second starting compound in a second substep of the PEALD method. The N 2 O can react with the trimethylaluminum adsorbed on the substrate 1 and the layer sequence 2 to form an Al 2 O 3- layer having a thickness in the range from less than 1 nm to several nanometers, which is preferably formed as a monolayer, however. The first and the second substep of the PEALD method are repeated immediately until a first barrier layer 3 10 to 30 nm thick is produced.By the PLALD method or the PEALD method, a high-density first barrier layer 3 can be produced which is distinguished by an excellent crystal structure and has no pores and / or channels or only hardly any pores or channels compared to a layer grown by means of a CVD method. Furthermore, the first barrier layer 3 produced in this way enables a high-density interface between the barrier layer 3 and, for example, the substrate 1 in the edge region of the encapsulation, whereby possible permeation paths for oxygen and / or moisture along these interfaces are avoided.In a further method step according to FIG. 1C, a PECVD method is used to apply second barrier layer 4 made of SiO 2 to first barrier layer 3. The second barrier layer 4 is applied with a thickness of about 100 nm to about 1000 nm at the same temperature as the first barrier layer 3. Due to the high-density first barrier layer 3, the second barrier layer 4 can be applied at a relatively higher growth rate in order to achieve an intrinsically dense encapsulation of the organic layer sequence 2.Overall, a high-density encapsulation is thus achieved with short process times in an economical method.The PLALD method or the PEALD method and the PECVD method are carried out in the same coating installation, so that during the production of the encapsulation with the first barrier layer 3 and the second barrier layer 4, no additional dead times arise as a result of loading and unloading of coating installations when changing from the PLALD method or from the PEALD method to the PECVD method.Alternatively or in addition to the materials described here, the first and / or the second barrier layer 3, 4 can comprise oxides, nitrides and / or oxynitrides with semimetals and / or metals as embodied in the general part. As an alternative to the method shown, the second barrier layer 4 can also be applied to the substrate and the organic layer stack 2 with the organic functional layer 22 upstream of the first barrier layer 3.Alternatively or additionally, the second electrode 23 can be transparent, so that the organic electronic component can be produced as a top emitter or as a transparent OLED. Alternatively or additionally, the layer sequence 2 can also comprise or be, for example, an organic transistor and / or an organic photodiode.FIG. 2 shows an exemplary embodiment of an organic electronic component which is produced by means of a method which has a further method step compared with the method according to the preceding exemplary embodiment.After the above-described application of the first and second barrier layers 3, 4, a protective layer 5 is furthermore applied. The protective layer 5 comprises a spray coating material, which can be, for example, a solvent-containing coating material, which is applied with a thickness of 10 to 100 μm in a continuous spray coating system. The protective layer 5 can effectively protect the organic electronic component and in particular the first and second barrier layers 3, 4 against scratches and other mechanical damage.Alternatively or additionally, a polymer, for example a silicone or epoxy resin, can also be applied as protective layer 5.The following figures show sections of organic electronic components according to further exemplary embodiments, which represent modifications and variations of the preceding exemplary embodiments.The following description relates mainly to the differences from the previous embodiments.FIG. 3 shows a section of an organic electronic component in which, as in the preceding exemplary embodiments, a high-density first barrier layer 3 made of Al 2 O 3 is applied over the layer sequence 2. A second barrier layer 4 is applied over it by means of a PECVD method, which has three layers 41, 42, 43 with a total thickness of 100 to 100 nm. The layers 41 and 43 are implemented as a silicon nitride layer, while the layer 42 is implemented as a silicon oxide layer. Alternatively, the materials of the layers 41, 43 and of the layer 42 can also be interchanged. Furthermore, the second barrier layer 4 can also have, for example, a layer sequence with five layers, which are formed alternately as silicon oxide and silicon nitride layers.As an alternative to the exemplary embodiment shown, the first barrier layer 3 can also be applied to the second barrier layer 4 having the layers 41, 42, 43.In FIGS. 4 and 5, sections of organic electronic components are shown, which comprise a plurality of first barrier layers 3, 3', 3'' and 3, 3', 3'', 3''' and a plurality of second barrier layers 4, 4', 4'', which are each applied alternately to one another by means of PLALD methods or PEALD methods or PECVD methods. Since it cannot be ruled out that the second electrode of the layer sequence 2 and / or the second barrier layers 4, 4', 4"at least partially have defects, for example in the form of columnar growth, channels, pores and / or grain boundaries, it can be ensured by the first barrier layers 3, 3', 3'' between the layer sequence 2 and the second barrier layers 4, 4', 4"that continuation of such defects can be effectively interrupted. In particular, channels and / or pores occurring in the second barrier layers 4, 4', 4"can be sealed by the first barrier layers 3', 3", respectively 3', 3", 3"' lying above.Furthermore, at least one of the second barrier layers 4, 4' and 4"can have a plurality of layers as shown in connection with the exemplary embodiment in FIG. 3.

Claims

Method for producing an electronic component having barrier layers for encapsulation of the component, having the steps: - providing a substrate (1) having at least one functional layer (22), - applying at least one first barrier layer (3) on the functional layer (22) by means of plasmaless atomic layer deposition (PLALD), and - applying at least one second barrier layer (4) on the functional layer (22) by means of plasma-enhanced chemical vapor deposition (PECVD), wherein a layer sequence of at least two layers (41, 42) having different materials is applied as the second barrier layer (4), and - applying a protective layer (5) on the first and second barrier layers (3, 4), wherein the protective layer (5) is made of a plastic and has a thickness of greater than or equal to 10 μm.Method according to the preceding claim, in which - the protective layer (5) comprises a spray lacquer.Method according to one of the preceding claims, in which - during the provision of the substrate (1) with the at least one functional layer (22), a first electrode (21) is applied to the substrate (1) and a second electrode (23) is applied to the at least one functional layer (22), - the functional layer (22) comprises an organic functional layer and - the first barrier layer (3) is applied to the second electrode (23).Method according to one of the preceding claims, in which - the first barrier layer (3) and / or the second barrier layer (4) comprises an oxide, a nitride or an oxynitride.Method according to one of the preceding claims, in which - the at least two layers (41, 42) with different materials comprise a layer with an oxide and a layer with a nitride.Method according to one of the preceding claims, in which - at least one further first barrier layer (3') and / or at least one further second barrier layer (4') is applied.Method according to one of Claims 5 or 6, in which - the first and second barrier layers (3, 3', 4, 4') are applied alternately to one another.Method according to one of the preceding claims, in which - the second barrier layer (4) is applied before the first barrier layer (3).Method according to one of the preceding claims, in which - the at least one first barrier layer (3) and the at least one second barrier layer (4) are applied at a substrate temperature of greater than or equal to 60°C and less than or equal to 120°C.Method according to one of the preceding claims, in which - the at least one first barrier layer (3) has a thickness of greater than or equal to 10 nm and less than or equal to 30 nm.Method according to one of the preceding claims, in which - the at least one second barrier layer (4) has a thickness of greater than or equal to 100 nm and less than or equal to 1000 nm.Method according to one of the preceding claims, in which - the electronic component comprises a light-emitting organic diode (OLED) and / or a solar cell.Organic optoelectronic component, producible by means of a method according to one of Claims 1 to 12.

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