DE102015109809A1 - Coated plastic substrate, organo-electric device and method for producing a coated plastic substrate - Google Patents

Abstract

The invention relates to a plastic substrate 2 coated with a permeation barrier layer, to an organoelectric component and to a method for producing a plastic substrate 2 coated with a permeation barrier layer.
The object of the invention is to provide a Permeationsbarriereschicht on a plastic substrate, which combines very good barrier properties and high transparency with each other.
For this purpose, the permeation barrier layer contains the elements silicon and / or aluminum as well as oxygen and nitrogen, the layer concentration ratio of the amount of nitrogen in the layer to the amount of oxygen in the layer at least 1: 4 in a layer without aluminum, at least 1: 4 in one Layer with silicon and aluminum and at least 2: 3 in a layer without silicon.

Description

The invention relates to a plastic substrate coated with a permeation barrier layer, to an organoelectric component and to a method for producing a plastic substrate coated with a permeation barrier layer.

Flexible polymer films with a barrier function have become indispensable in industrial applications today. The increasing efficiency of newly developed barrier films opens up completely new fields of application. In the meantime, inflexible barrier material such as glass can be replaced by flexible high-barrier films. This leads to new products, as they are currently being developed, especially in the field of polymer electronics. Examples are flexible LC or OLED displays ( S. Amberg-Schwab, in: "Handbook of Sol-Gel-Science", Vol.3, 2003 ; K. Jopp, SCHOTT-Info, 99, 2001, 21 ; H. -Ch. Langowski, Galvanotechnik, 11, 2003, 2800 ; T. Dobbertin, E. Becker, T. Benstem, H.-H.-Johannes, D. Metzdorf, H. Neuner, W. Kowalsky, Carolo Wilhelmina, 1, 2002, 70 ) or printed circuits for transponder chips.

Other components, such as flexible solar cells ( S. Amberg-Schwab, in: "Handbook of Sol-Gel-Science", Vol.3, 2003 ), are not feasible without polymer films with high barrier function. The search for new and better barrier materials remains a challenge.

In principle, in addition to influencing the material morphology, there are three possibilities for increasing the barrier effect in plastics: use of another material (blends, nanocomposites), multilayer composites or thin-film technologies (paint-based coatings, PVD - Physical Vapor Deposition, PE-CVD-plasma -enhanced chemical vapor deposition, plasma-activated chemical vapor deposition).

Only in the case of plasma-assisted thin-film technologies is the necessary barrier property achieved even at very small layer thicknesses in the range of 20 nm to 200 nm. For example, today polymer films are available, which have in combination with a vapor-deposited PVD layer of AlO _x or SiO _x so low permeability to oxygen and water vapor that food can be protected within the specified shelf life from oxidation, moisture or loss ,

Such coated polymer films are industrially manufactured in large quantities and are available at low prices. They achieve (based on a 12 μm PET film with an inorganic layer) an oxygen transmission rate (OTR: oxygen transmission rate) of less than 1 cm ³ / (m ² · dbar) and a water vapor permeability (WVTR: Water Vapor Transmission rate) below 0.1 g / (m ² · d).

The latter means that 0.1 g of water can diffuse through 1 m ^{2 of} a plastic film under the frame parameters within one day.

Also permeation barrier layers of zinc-tin oxide, which can be applied by sputtering on a plastic, are known.

The company General Atomics, which has developed a roll-to-roll process for coating flexible PC films with alumina (about 80 nm), even achieves a water vapor transmission of 10 ^-4 g / (m ² · d).

However, layers of alumina or zinc-tin oxide have the disadvantage of insufficient properties outside the permeation properties, such as poor optical properties, in particular poor transparency.

One way to achieve better optical properties is the use of silicon oxide as a layer material. Thus, for example, it is possible to set the refractive index smaller than 1.5. However, it has been found that a permeation barrier layer made of a silicon oxide has poor permeation barrier properties. Thus, a silicon oxide layer at 90% humidity and at 38 ° C ambient temperature, a water vapor permeability of 1 g / m ² / d. This is unacceptable for many applications in which the substrate, in particular the plastic film, is to be provided with further layers for the production of further properties.

Alternatively, transparent barrier layers can also be applied by means of plasma polymerization in the low-pressure region (PE-CVD) economically and environmentally friendly as a thin layer on plastics ( B. Jacoby, W. Bock, M. Haupt, H. Hilgers, M. Kopnarski, J. Molter, C. Oehr, T. Rühle et al.: Deposition, characterization and application of HMDSO-based plasma polymer layers. In: Vacuum in Research and Practice Bd. 18 (2006), No. 4, pp. 12-18 . H. Kobayashi, AT Bell, M. Shen: Plasma Polymerization of Saturated and Unsaturated Hydrocarbons. In: Macromolecules Bd. 7 (1974), No. 3, pp. 277-283 ; H. Yasuda, Y. Matsuzawa: Economical Advantages of Low-Pressure Plasma Polymerization Coating. In: Plasma Processes and Polymers Vol. 2 (2005), No. 6, pp. 507-512 ).

The plasma polymerization is based essentially on the excitation of gases to a reactive plasma by means of energy coupling and the deposition of the activated molecular fragments on the substrate surface ( A. Grill: Cold Plasma in Materials Fabrication, The Institute of Electrical Engineers and Electronics, Press. In: Inc., New York (1994), pp. 2-5 ). The plasma-activated molecules and molecular fragments polymerize on the substrate surface to form a highly cross-linked functional plasma polymer layer. The non-reacted in the plasma residual gases are removed by vacuum pumps the process.

For technical applications with high demands on the oxygen and water vapor barrier properties, however, this technology is not sufficient. A clear increase in the barrier properties can be achieved by a multi-layer structure. This essentially ensures a covering of defects due to macroscopic defects on the film surface, as they are caused for example by anti-blocking agent, pores or dust.

There is general consensus in the literature that layer defects are critical to barrier properties. It is therefore necessary to deposit as low-defect layers and layer systems. For this purpose, different strategies are pursued.

On the one hand, many investigations are aimed at providing the highest possible and perfectly smooth substrate surface. This is indeed a very effective approach because permeation barrier layers generally can not cover substrate defects. It is already possible to purchase films with special planarization layers from some manufacturers (eg TEONEX ^® Q65FA). Simpler solutions are to avoid antiblocking particles on one side of the film (eg PET MELINEX ^® 400). The best Permeationsbarriereschichtsysteme manufactured today have several intermediate layers on with planarizing effect that part of the coating process themselves (eg. As ORMOCER® ^®, flash evaporation of acrylate).

On the other hand, it is necessary to keep an eye on the coating process itself as a source of possible defects. In the case of PE-CVD processes, for example, agglomeration in the gas phase can occur. But layer defects can also be observed in sputtering processes.

Furthermore, barrier layers can be produced as a single layer by means of atomic layer deposition (ALD). Due to its particularly conformal coverage of the substrate surface and very dense layers, the ALD shows very good barrier properties (water vapor permeability of <10 ^-3 g / (m ² · d)), but currently still has a low productivity.

To achieve particularly good barrier properties, the actual barrier layer is currently combined with one or more polymer layers. The purpose of the polymer layers is to disrupt the growth of defects, level the surface, cover particles and, compared to a thick single layer, reduce stress in layers and the tendency to crack. Typically, lower water vapor permeabilities are achieved with layer systems than with single layers. The lowest values are below 10 ^-5 g / (m ² · d) in a stationary process. For roll-to-roll processes, values in the range of 10 ^-3 to 10 ^-4 g / (m ² · d) are published.

Technical applications, such. As LEDs and inorganic solar cells in the electronic field, require barrier layers that are well above the barrier options that are currently state of the art in technical films or film composites. Organic solar cells and OLEDs (Organic Light Emitting Diode) place the highest demands on encapsulation because they are extremely sensitive to oxygen and water vapor.

In addition, the requirement is made for novel ultra-high barriers to make a flexible encapsulation possible. Conventionally, such oxygen and water vapor sensitive products are encapsulated with glass plates, which is expensive and above all brings unnecessary weight.

Current ultra-barrier concepts are based on the combination of hybrid polymer barrier coatings such. B. ORMOCER ^® , and inorganic PVD barrier layers. The layer properties of both barrier materials are exploited in synergies to compensate for potential barrier defects.

Of interest are developments which realize a significant weight saving, recognizable lower material and manufacturing costs (low cost roll-to-roll production) and new application areas and product geometries.

It is the object of the invention to specify a permeation barrier layer on a plastic substrate which combines very good barrier properties and high transparency with one another.

Preferably, such barrier properties should be achieved with a single barrier layer, as in the current state of the art can only be achieved with layer systems consisting of several individual layers.

Furthermore, a method is proposed, with the use of a tubular magnetron such Permeationsbarriereschicht with improved properties and while ensuring good productivity on plastics, especially plastic films can be applied.

More preferably, the method should be suitable for implementation in a role-to-role process.

In addition, a possibility should be provided with which a flexible encapsulation, in particular of OLEDs and organic solar cells, can be realized.

This object is achieved with a coated plastic substrate having the features of claim 1 and an organo-electrical component having the features of claim 4. A manufacturing method for a plastic substrate coated with such a permeation barrier layer has the features of claim 6. The respective dependent subclaims show favorable embodiments.

A permeation barrier layer according to the invention on a correspondingly coated plastic substrate contains the elements silicon and / or aluminum as well as oxygen and nitrogen. The layer concentration ratio of the amount of nitrogen in the layer to the amount of oxygen in the layer is at least 1: 4 in a layer without aluminum, at least 1: 4 in a layer with silicon and aluminum and at least 2: 3 in a layer without silicon.

By way of clarification, it should be pointed out that the ratios given are the molar ratio of the elements nitrogen and oxygen, averaged over the layer thickness. This molar ratio can be determined for example by means of Glow Discharge Optical Spectroscopy.

It is possible that the permeation barrier layer contains silicon, aluminum or both. In principle, however, the permeation barrier layer always consists of an oxygen and nitrogen-containing compound, for example of a silicon-oxy-nitride, an aluminum-oxy-nitride or a mixture of both.

It has been found that a proportion of 15 mol% of nitrogen in the layer already gives an improvement in the permeation barrier properties in comparison to a purely oxidic layer. At 20 mol% they are much better. Pure nitrides are less suitable because of their brittleness, especially for soft plastic substrates.

At the same time, the plastic substrate according to the invention coated with a permeation barrier layer has a high optical transparency in the visible light range, such as in FIG 5 can be seen for a Siliziumoxinitridschicht with a layer thickness of about 200 nm.

Thus, with a polyethylene terephthalate (PET) film having a thickness of 75 μm, it has been found that with a permeation barrier layer having a thickness of 100 nm with the addition of nitrogen in the permeation barrier layer, a water vapor permeability of 0.15 g / m ² / d and even reach only 0.07 g / m ² / d in a 300 nm thick layer.

The oxygen permeability behaves similarly.

According to one embodiment variant, the coated plastic substrate consists of polyethylene terephthalate (PET). "Passes out" refers to the polymer material of the plastic. In addition, additives such as plasticizers, stabilizers, colorants, flame retardants, reinforcing agents or fillers may be included.

According to a further embodiment, the plastic substrate is a plastic film. By foil is meant a thin sheet having a thickness of less than 1 mm, preferably less than 500 μm, more preferably less than 100 μm.

The main advantage of films is their flexibility, so that they can be used, for example, for the production of flexible displays or flexible solar cells. In addition, they are characterized by a very low material consumption.

The plastic substrate coated with a permeation barrier layer according to the invention may be part of an organo-electrical component, so that a corresponding organo-electrical component has a coated plastic substrate according to the invention as described above.

Such organo-electrical components, for example, organic light emitting diodes, z. B. for displays or lights, and / or organic solar cells.

By using the plastic substrate coated according to the invention, a flexible encapsulation is made possible, which has very good barrier properties, while optical Impairments can be minimized or even completely avoided.

Such an encapsulation also has a very low weight and helps to reduce the material and manufacturing costs of OLEDs and organic solar cells as well as to enable new areas of application and product geometries.

According to the invention, the plastic substrate coated with a permeation barrier layer is produced by moving the plastic substrate in a transport direction in a coating area of a continuous sputtering machine and the permeation barrier layer by sputtering at least one tubular magnetron with a target in the coating area on the plastic substrate is deposited.

The tubular magnetron comprises at least one tubular target and a magnet system arranged in the tube.

Conventional planar magnetrons have large amounts of transition zones between sputter trench and back dust zones on their targets. There are significant electrical potential differences between the two areas during operation, which can lead to plasma arc discharges and thus to the formation of defects.

In contrast, tube targets have only a very small transition area between the sputtering area and the back-dusting zone, which is also far outside the coating area. The defects caused by the plasma process itself can be significantly limited in their density and thus also in their negative effect.

In addition, tube magnetrons cause less heat input into the substrate compared to planar magnetrons. This effect is mainly due to two causes. On the one hand, the emission of high-energy oxygen ions from the target surface is defocused and, on the other hand, the electrons can reach the anode unhindered by a magnetic shield.

This is particularly important in the case of the plastic substrates considered here, since they have a significantly higher heat sensitivity compared to otherwise used metal and glass substrates. Optionally, the sputtering can also be done by a dual-tube magnetron.

Discharge space is the space of the plasma discharge that forms between the cathode and the anode. For transporting the substrate through the sputtering system, a substrate transport device may be provided. In the case of a roll-to-roll sputtering system, the rolls can serve as a substrate transport device for winding and unwinding. A layer deposition on the substrate takes place in the coating area in the discharge space.

The sputtering technology is significantly more productive, especially compared to wet-chemical processes, as it can be carried out in optimized continuous flow systems. It also allows the implementation of the coating step within a roll-to-roll process, so that manufacturing costs can be further reduced.

According to one embodiment variant, a reactive gas which has nitrogen and / or oxygen is introduced into the coating area. This allows the deposition of the permeation barrier layer in a reactive process.

The deposition of the permeation barrier layer preferably takes place by means of two tubular magnetrons (dual tube magnetron), both magnetrons being operated in a bipolar mode in which both magnetrons are switched alternately as anode or cathode.

The bipolar mode can be achieved for example by means of a bipolar power supply, wherein the polarity of the power supply with a frequency in the order of between 5 kHz and 250 kHz, preferably in the range between 10 and 100 kHz, more preferably between 40 and 60 kHz, changes.

With this process design, neutralization is achieved from the charges that build up on insulating regions of the target. Additional effects are the realization of a reliable anode and the realization of a plasma density on the substrate, which is higher compared to DC processes. The factors mentioned contribute to the stability of the discharge, which is ultimately a prerequisite for the deposition of a useful layer with good barrier properties.

Preferably, the permeation barrier layer is deposited in a reactive process, wherein a nitrogen-containing and an oxygen-containing gas are supplied to the discharge space in a slice concentration ratio adjusting dosage.

A reactive process is understood as meaning a sputtering process in which the gas discharge deliberately receives a certain amount of one or more reactive gases, in this case oxygen and oxygen nitrogen-containing gases are supplied. The aim is to deposit on the substrate a bonding layer between the material of the sputtering target and the chemical components of the reactive gas. The reactive process is characterized by containing less than 10 ⁵ ppm (parts per million) of oxygen or nitrogen in the material of the sputtering target.

In the case of reactive deposition, the target consists of silicon and / or aluminum. In the case of the use of two tubular magnetrons with correspondingly two targets, this comprises the following variants: both targets of silicon, both targets of aluminum, a target of silicon together with a target of aluminum. It is also possible to use targets in which aluminum and silicon are alloyed.

The concentrations of the reactive gases will be adjusted to adjust the concentration ratio in the layer according to their reactivity. So oxygen has a higher reactivity than nitrogen. Thus, for example, it is desirable to reduce the oxygen concentration at the reactive gas ratio by 5 to 7% in comparison to the concentration ratio in the layer, or to correspondingly increase the nitrogen concentration.

Benefits of using a reactive process include the lower cost of a metallic target compared to ceramic targets. On the other hand, sputtering from a metallic target allows a higher coating rate since aluminum and silicon have a higher sputter yield compared to their oxides and nitrides. Usually the operating point with the highest coating rate is selected.

In the case of using a dual-tube magnetron, the supply of the nitrogen-containing and the oxygen-containing gas preferably takes place together via a gas channel, which is arranged between the two tubular magnetrons.

This reactive gas channel extends at least over the entire width of the target. It is preferably divided into three segments, so that a middle segment is enclosed by two edge segments. Of course, a subdivision into more than three segments is possible, wherein a middle segment is enclosed on both sides by edge segments. The total number of segments is therefore always odd.

Such a segmentation allows more accurate metering of the supplied reactive gas, for example, taking into account so-called edge effects. Thus, it is possible to produce particularly homogeneous permeation barrier layers, in particular also transversely to the transport direction.

According to one embodiment, the gas flow for each segment is controlled separately by means of a gas flow regulator. It has proved to be advantageous if the edge segments allow a respective preset, but kept constant gas flow in the discharge space, while the middle segment can be optionally incorporated into a control loop. As a reference variable of the control loop can serve the discharge voltage.

The mixing ratio of oxygen and nitrogen can be realized, for example, via a master-slave interconnection of two MKS type gas flow controllers. This principle can optionally be applied both for an actively regulated inlet over the middle segment and for the two gas flows of the edge segments. Thus, in each case, a respectively constant mixing ratio of oxygen and nitrogen can be admitted.

The supply of the inert gas, for example argon, preferably takes place via a continuous gas channel with uniformly distributed openings, which is arranged between the two magnetrons. This arrangement allows the most uniform possible gas distribution in the discharge space and thereby favors the formation of a homogeneous as possible barrier layer.

Preferably, both gas channels are arranged centrally between the targets on the substrate side facing away from the targets.

According to a further embodiment, determined parameters of the magnetron plasma are determined and from this, directly or indirectly, the supplied gas quantity is set such that the layer concentration ratio remains constant over the length of the moving substrate.

Such parameters may be, for example, certain spectral lines or the partial pressures of the gas components in the sputtering atmosphere. For example, the composition of the supplied gas quantity can be determined directly by means of plasma emission spectroscopy. An indirect determination of the composition can be made by means of the partial pressures.

The selected parameter serves as a controlled variable for regulating the gas supply. If the dependence of the layer composition on the composition of the sputtering atmosphere is known, the parameters of the plasma can be used to adjust the layer concentration ratio.

Due to the process control, it is possible to react to changes during the sputtering process, so that the layer concentration ratio remains constant over the length of the moving substrate.

In one embodiment, the power of the gas discharge can be adjusted by means of one or more characteristic measured variables of the magnetron plasma so that the parameters of the magnetron plasma, in particular the gas composition in the magnetron plasma, remain constant.

Such characteristic measured variables can be, for example, the partial pressures of the gases, certain spectral lines as well as the voltage and current intensity at the target.

The invention will be explained in more detail with reference to two embodiments. The accompanying drawings show:

1 Highly simplified representation of a sputtering apparatus for producing the permeation barrier layer according to the invention transversely to the longitudinal extent of the targets,

2 Schematic representation of the gas inlet system for producing the permeation barrier layer according to the invention viewed in the longitudinal direction from the substrate,

3 Dependence of water vapor permeation on different silicon oxynitride layers, sputtered by a dual tube magnetron, on the layer thickness,

4 Dependence of water vapor permeation on different aluminum oxynitride layers, sputtered by a dual tube magnetron, on the layer thickness,

5 Dependence of the transmission on the wavelength for a silicon oxynitride permeation barrier layer according to the invention in comparison with a silicon nitride layer,

6 Dependence of the water vapor permeation on the layer thickness for an aluminum oxynitride layer according to the invention in comparison to an aluminum nitride and an aluminum oxide layer.

According to a first example, the permeation barrier layer contains a plastic substrate coated with this permeation barrier layer 2 the elements silicon as well as oxygen and nitrogen. The layer concentration ratio of the amount of nitrogen in the layer to the amount of oxygen in the layer is at least 1: 4.

According to a second example, unlike the first example, the permeation barrier layer contains the elements aluminum as well as oxygen and nitrogen. The layer concentration ratio of the amount of nitrogen in the layer to the amount of oxygen in the layer is at least 2: 3.

The permeation barrier layers of both examples are coated with the sputtering system described below on the plastic substrate 2 deposited.

At the sputtering plant 1 it is a roll-to-roll sputtering machine 1 with two rotating magnetrons, each with a tube target 6 and a magnet system 7 , a device for gas supply 11 and a discharge room 12 in which in a coating area 3 in the discharge room 12 a layer deposition takes place. ( 1 ). As a substrate transport device 5 serve the rollers (cooling rollers) for winding and unwinding of the plastic substrate 2 containing the plastic substrate 2 in a transport direction 4 move.

The middle between the two tubular magnetrons 8th arranged device for gas supply 11 comprises two separate gas channels ( 2 ). A first gas channel, the inert gas channel 9 , is used to supply argon. The inert gas channel 9 is as a continuous gas channel with evenly distributed openings for the inlet of the inert gas in the discharge space 12 educated. In the example, a gas flow of 200 sccm is set, which leads to an argon partial pressure of 0.4 Pa according to the locally effective pumping speed of the pumps.

A second gas channel, the reactive gas channel 10 , is used to supply nitrogen and oxygen. The reactive gas channel 10 is in three segments, a middle segment 13 and two edge segments 14 , Subdivided, each openings to inlet of the reactive gas in the discharge space 12 exhibit. The edge segments 14 serve to correct the coating unevenness arising during the sputtering process. The edge segments are assigned a gas flow regulator, which has a respectively preset, but then held constant gas flow into the discharge space 12 allows.

In contrast, the middle segment 13 involved in a control loop. As a reference variable for the control loop, the discharge voltage acts as an actuator, a fast gas flow regulator.

The mixing ratio of oxygen and nitrogen is realized via a master-slave interconnection of two MKS-type gas flow controllers. This principle applies to both actively regulated intake over the middle segment 13 as well as for the two gas flows of the edge segments 14 applied. Thus, in each case a constantly set mixing ratio of oxygen and nitrogen is admitted. The mixing ratio is chosen so that the desired layer concentration ratio is established in the permeation barrier layer.

The two tubular magnetrons 8th are operated in a bipolar mode in which both magnetrons 8th alternately switched as anode or cathode. There is a bipolar power supply. The polarity of the discharge changes with a frequency of 50 kHz.

As a plastic substrate 2 a polyethylene terephthalate film with a thickness of 75 microns was used.

In the first embodiment for producing a silicon-containing permeation barrier layer are used as targets 6 Silicon targets with a purity of> 99.5% used.

The dependence of the water vapor permeability on the layer thickness of the permeation barrier layer for different oxygen-to-nitrogen layer concentration ratios is in 3 shown. In 3 It can be seen that only for N: O ratios of at least 1: 4 acceptable water vapor permeabilities are achieved. 5 shows the dependence of the transmission on the wavelength.

In the second embodiment for producing an aluminum-containing permeation barrier layer are used as targets 6 Aluminum targets used with a purity of> 99.5%.

The dependence of the water vapor permeability on the layer thickness of the permeation barrier layer for different oxygen-to-nitrogen layer concentration ratios is in 4 shown. In 4 It can be seen that only for N: O ratios of at least 2: 3 acceptable water vapor permeabilities are achieved. The improvement of water vapor permeation compared to an aluminum nitride and an aluminum oxide layer illustrates 6 ,

LIST OF REFERENCE NUMBERS

1

Sputter

2

Plastic substrate

3

coating area

4

transport direction

5

Substrate transport apparatus

6

target

7

magnet system

8th

tubular magnetron

9

inert-gas

10

Reactive gas channel

11

Device for gas supply

12

discharge space

13

middle segment of the reactive gas channel

14

Edge segment of the reactive gas channel

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited non-patent literature

• S. Amberg-Schwab, in "Handbook of sol-gel Science", Vol.3, 2003 [0002]
• K. Jopp, SCHOTT-Info, 99, 2001, 21 [0002]
• H. -Ch. Langowski, Galvanotechnik, 11, 2003, 2800 [0002]
• T. Dobbertin, E. Becker, T. Benstem, H.-H.-Johannes, D. Metzdorf, H. Neuner, W. Kowalsky, Carolo Wilhelmina, 1, 2002, 70 [0002]
• S. Amberg-Schwab, in: "Handbook of Sol-Gel-Science", Vol.3, 2003 [0003]
• B. Jacoby, W. Bock, M. Haupt, H. Hilgers, M. Kopnarski, J. Molter, C. Oehr, T. Rühle et al.: Deposition, characterization and application of HMDSO-based plasma polymer layers. In: Vacuum in Research and Practice Bd. 18 (2006), No. 4, pp. 12-18 [0012]
• H. Kobayashi, AT Bell, M. Shen: Plasma Polymerization of Saturated and Unsaturated Hydrocarbons. In: Macromolecules Bd. 7 (1974), No. 3, pp. 277-283 [0012]
• H. Yasuda, Y. Matsuzawa: Economical Advantages of Low-Pressure Plasma Polymerization Coating. In:.. Plasma Processes and Polymers Vol 2 (2005), No. 6, pp 507-512 [0012]
• A. Grill: Cold Plasma in Materials Fabrication, The Institute of Electrical Engineers and Electronics, Press. In: Inc., New York (1994), pp. 2-5 [0013]

Claims (13)

Plastic substrate coated with a permeation barrier layer ( 2 ), wherein the permeation barrier layer contains the elements silicon and / or aluminum as well as oxygen and nitrogen, wherein the layer concentration ratio of the amount of nitrogen in the layer to the amount of oxygen in the layer at least 1: 4 in a layer without aluminum, at least 1: 4 in a layer of silicon and aluminum and at least 2: 3 in a layer without silicon. Coated plastic substrate ( 2 ) according to claim 1, wherein the plastic substrate ( 2 ) consists of polyethylene terephthalate (PET). Coated plastic substrate ( 2 ) according to claim 1 or 2, wherein the plastic substrate ( 2 ) is a plastic film. Organo-electric device comprising a coated plastic substrate ( 2 ) according to one of claims 1 to 3.  Organo-electrical component according to claim 4, wherein the organo-electrical component comprises an organic light emitting diode and / or an organic solar cell. Process for producing a plastic substrate coated with a permeation barrier layer ( 2 ) according to one of claims 1 to 3, wherein the plastic substrate ( 2 ) in a transport direction in a coating area ( 3 ) within a discharge space ( 12 ) of a continuous sputtering system ( 1 ), in the coating area a reactive gas comprising nitrogen and / or oxygen is introduced and the permeation barrier layer by means of sputtering of at least one tubular magnetron ( 8th ) with a target ( 6 ) in the coating area ( 12 ) on the plastic substrate ( 2 ) is deposited. Process according to claim 6, wherein the permeation barrier layer is formed by means of two tubular magnetrons ( 8th ), both tubular magnetrons ( 8th ) are operated in a bipolar mode in which both tube magnetrons ( 8th ) can be switched alternately as anode or cathode.  The method of claim 7, wherein the bipolar mode is achieved by means of a bipolar power supply, wherein the polarity of the power supply with a frequency in the order of between 5 kHz and 250 kHz, preferably in the range between 10 and less than 100 kHz, more preferably between 40 and 60 kHz, changes. Method according to one of claims 6 to 8, wherein the permeation barrier layer in a reactive process with a target ( 6 ) is deposited from silicon and / or aluminum, wherein a nitrogen-containing and an oxygen-containing gas the discharge space ( 12 ) are fed in a dosage adjusting the coating concentration ratio. The method of claim 9 at least in combination with claim 7, wherein the supply of the nitrogen-containing and the oxygen-containing gas together via a into at least three segments ( 13 . 14 ) subdivided gas channel ( 10 ), which between the two tube magnetrons ( 8th ) is arranged. The method of claim 9 at least in combination with claim 7 or claim 10, wherein the supply of the inert gas via a continuous gas channel ( 9 ) with uniformly distributed openings, which between two magnetrons ( 8th ) is arranged. Method according to one of claims 6 to 11, wherein determined parameters of the magnetron plasma are determined, from which, indirectly or directly, the supplied gas quantity is adjusted so that the layer concentration ratio over the length of the moving plastic substrate ( 2 ) remains constant.  Method according to one of claims 6 to 12, wherein by means of one or more characteristic magnitudes of the magnetron plasma, the power of the gas discharge is adjusted so that the parameters of the magnetron plasma remain constant.

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