WO2012028809A1

WO2012028809A1 - Support for organic-light-emitting-diode device, such an organic-light-emitting-diode device and process for manufacturing said device

Info

Publication number: WO2012028809A1
Application number: PCT/FR2011/051972
Authority: WO
Inventors: Fabien Lienhart; Georges Zagdoun; Marie-Virginie Ehrensperger
Original assignee: Saint-Gobain Glass France
Priority date: 2010-08-30
Filing date: 2011-08-29
Publication date: 2012-03-08
Also published as: JP2013536977A; FR2964254A1; EP2612379A1; CN103190012A; FR2964254B1; KR20130106832A

Abstract

The invention relates to a support (10) for an organic-light-emitting-diode device (1000) comprising a transparent substrate (1) of given first optical refractive index n1, comprising: a dielectric grating (3) in the form of one or more layers arranged discontinuously so as to form an array of what are called low-index patterns (30), the grating having a second optical refractive index n2 of 1.6 or less, the low-index patterns being submicron-sized in height, the average pattern width A1 being 6 µm or less and the distance B1 between micron-sized patterns being larger than the width A1; and a first electrode (4), with a given third optical refractive index n3 of 1.7 or more. The distance B1 is aperiodic. At least some of the thickness of the first electrode (4) is above said grating (3) and makes contact with the surface of the grating (3) which is furthest from that substrate (1), or is spaced apart from the grating (3) of low-index patterns. The grating (3) is buried in a high-index medium (100) and is therefore inside the high-index medium, the high-index medium comprising the first electrode (4) in the form of the one or more layers furthest from the substrate, the high-index medium having a fourth refractive index n4 of 1.7 or more. The invention also relates to the process for manufacturing such a support.

Description

The invention relates to an organic electroluminescent diode device holder, said device and its manufacture.

An OLED device (for "Organic Light Emitting Diodes" in English) comprises a material or a stack of organic electroluminescent materials, and is framed by two electrodes, one of the electrodes, the anode in general, being constituted by that associated with the glass substrate and the other electrode, the cathode in general, being arranged on organic materials opposite the anode.

OLED emits light by electroluminescence using the recombination energy of holes injected from the anode and electrons injected from the cathode. In the case where the electrode associated with the substrate is transparent, the emitted photons pass through this transparent electrode as well as the glass substrate supporting the OLED to provide light outside the device.

An OLED usually finds its application in a display screen or more recently in a lighting device.

For a lighting system, the light extracted from the OLED is preferably a "white" light emitting in some or all wavelengths of the visible spectrum. It must be so in a homogeneous way. On this subject we speak more specifically of a Lambertian emission, that is to say obeying Lambert's law, being characterized by a photometric luminance equal in all directions.

An OLED has a low light extraction efficiency: the ratio between the light that actually leaves the glass substrate and that emitted by organic electroluminescent materials is relatively low, of the order of 0.25. This phenomenon is explained in particular by the fact that a certain amount of photons remains trapped between the cathode and the anode.

It is therefore sought solutions to improve the efficiency of an OLED, namely to increase the extraction gain while providing a light, preferably white, and the most homogeneous possible. Homogeneous in the following description, homogeneity in intensity, and in space.

It is also known to provide at the glass-anode interface either a diffusing layer formed by a binder and diffusing particles or a structure with periodic projections, which constitutes a diffraction grating and thus makes it possible to increase the gain in extraction. US 2004/0227462 shows for this purpose an OLED whose transparent support substrate of the anode and the organic layer is textured. The surface of the substrate thus has an alternation of excrescences and recesses, the profile of which is followed by the anode and the organic layer, deposited thereon. The profile of the substrate is obtained by applying a photoresist mask on the surface of the substrate whose pattern corresponds to the desired one of the growths, then etching the surface through the mask. However, such a method is not easy to implement industrially on large substrate surfaces, and is above all too expensive, especially for lighting applications.

This network of the prior art optimizes the extraction gain around a certain wavelength but on the other hand does not promote a white light emission, on the contrary, it tends to select certain wavelengths and will emit example more in blue or red.

The document US 2006/0192483 for its part proposes to arrange on the glass substrate a two-dimensional silica diffractive grating having distinct periodicities as a function of the regions along a given translation vector to overcome the lack of uniformity of the luminance.

This diffractive grating is possibly surmounted by a high-index layer ZnO plane surface, to avoid electrical failures, and then the transparent anode ITO. The length of the periodicity is between 80% and 120% of the periodic average length. The length of the periodicity is between 0.1 μηη and 5 μηη. The height of the network is between 80% and 120% of the average height. The height of the network is between 50 nm and 20 μηη.

Again, the extraction of white light is not satisfactory.

WO 2008/121414 proposes a structure which consists in inserting between the organic electroluminescent system of refractive index 1, 7 -1, 8 and the first electrode a gate of optical index between 1 and 1.5. This grid according to the examples is hexagonal or rectangular. The low index material is selected from silica, TiO ₂ , airgel (silica, carbon, alumina, etc.), Teflon.

According to the tests, the grid is wide of 0.5 to 1, 2 μηι, the grid is spaced from 4 to

8 μηι. In a preferred example, the gate is 0.8 μηη wide spaced 5 μηη and the first electrode is 100 nm thick ITO.

This proposed structure certainly improves the extraction of light, but the light output is not satisfactory. The object of the invention is to propose a support for an alternative OLED device, with both a gain in light extraction (white in particular) from the satisfactory OLED and with a satisfactory luminous power, in particular a simple support to manufacture at the same time. industrial scale, and reliable, cheaply.

The present first object is a support for an organic light-emitting diode device comprising:

a transparent substrate of first optical refractive index n1 given with a first so-called internal main face and a second so-called external main face, the internal face comprising:

a (mainly) dielectric network, in particular a non-metallic network, in the form of a layer (s) arranged in a discontinuous manner, thus forming a set of so-called low-index patterns, the grating having a second n2 lower optical refractive index or equal to 1, 6, the low-index patterns being of submicronic height, of average width A1 of patterns less than or equal to 6 μηη, and l (d) the patterns being disjoint and the adjacent patterns then being spaced apart by a given intermotive distance and / or where the patterns are interconnected, in particular in a grid, with a given intramotive distance, the distance B1, which is the mean of the intermotive and / or intramotiv distances, is micron greater than the width A1 and less than or equal to 50 μηη, the distance B1 being aperiodic,

a first electrode, in particular a transparent electrode, in the form of a layer (s) with a given third optical refractive index n3 greater than or equal to 1.7, the first electrode having a square resistance of less than 30 ohm per square, preferably less than 10 ohm per square, more preferably less than 5 ohms per square.

In addition,

at least a fraction of a thickness of the first electrode is above said network and in contact with the surface of the grating farthest from the substrate or is spaced from the pattern network low index (by an underlying layer), the network is buried in a high index medium, the high index medium comprising the first electrode as the layer (s) furthest from the substrate, the high index medium having a fourth refractive index n4 greater than or equal to 1.7 .

On the one hand, with respect to the OLED proposed in document WO 2008/121414, the extraction of the OLED according to the invention is comparable, or even improved because the low patterns index lie at the heart of the high index guiding structure (including the OLED system and the high index medium of the invention including the first electrode) thus effectively diffusing light.

The Applicant has furthermore found that since a large part of the anode of the device of the prior art is covered by this low insulating electrical index material, all this surface of the final OLED of the prior art is inactive. . Drastically reducing the thickness of the strands or considerably increasing the spacing between the strands could increase the active area of the OLED, but this at the expense of extraction efficiency. Thus a compromise that would optimize the active surface while maintaining a correct light extraction would not find the entire active surface.

According to the invention, the low index patterns (for index contrast with the high index medium) are below the OLED system and covered (at least in part) by the first electrode so that the whole of the OLED according to the invention is electrically active, which makes it possible to increase the emitted light power while maintaining excellent light extraction performance.

A very weak supra-pattern conduction (on, above the patterns) is enough to distribute the current.

On the other hand, with respect to the OLED proposed in the document US 2006/0192483, the light extraction of the OLED according to the invention is improved whether it is polychromatic light (especially white light). , for general lighting in particular) or monochromatic (for decorative lighting for example). Indeed, this diffractive grating of the prior art only makes it possible to improve light extraction selectively, adding a strong angular (harmful for any type of light) and colorimetric (detrimental to white light) dependence of the light emission. , the different diffraction orders having very marked angular emission profiles.

Thus, the aperiodic, even random, nature of the distance B1 between the patterns over the entire low-index network according to the invention makes it possible to obtain an angular distribution of the almost Lambertian transmitted light and a gain in extraction for a broad band of wavelengths (no visible color effect). There are no diffraction effects.

In addition, the width of the patterns of the network can improve the extraction power without fear of diffraction.

The average width A1 (or even the maximum width) of the patterns of the grating is preferably less than or equal to 3 μηη and greater than 100 nm. In the present invention, the term buried network in a substantially high-index medium, a network inside a substantially high-index medium, and means buried network in a high-index medium, a network within a high index medium, a high index medium.

In the present invention, the term "optical refractive index" means the refractive index measured at 550 nm.

This may be the average index in the case of continuous multilayers (multilayer background layer and / or multilayer network and / or multilayer electrode and / or multilayer organic electroluminescent system ...). The average index of continuous multilayers is defined by the sum of the indices n, when the thickness e, of each layer on the total thickness e of the medium is

n _i .e _i I e.

The high index medium is essentially high index in the sense that it can understand (outside the network naturally) without being penalized:

a low index layer, substantially continuous, with an occupation ratio> 90%, refractive index less than 1, 7, thickness less than or equal to 20 nm, or even 10 nm,

or a plurality of so-called low index layers, each substantially continuous, with a degree of occupancy> 90%, of refractive index less than 1, 7, with a thickness of less than or equal to 20 nm, especially spaced apart from one another by distance less than 40 nm, or even 20 nm or even 10 nm,

the low layer or layers having a thickness (cumulative if several layers) less than 0.20 times the thickness of the medium high index.

In the present invention, in the absence of precision, a high index layer (or coating) is defined as having a refractive index greater than or equal to 1.7.

In one configuration, the high-index medium may comprise a first so-called planarized grid electrode formed of a discontinuous metal layer, arranged above the grating and above the inter-pattern space, with a occupancy level <to 20%, in particular arranged in grid, and covered (to be planarized) by an electroconductive coating called high index planarization, in the form of transparent layer (s).

The index n3 of this first planarized grid electrode is then specifically defined as the index of the high-index coating (average index of the planarizing coating, if it has a multilayer structure).

Preferably:

the transparent substrate (bare) has a light transmission (TL) of minus 70%, even 80% and beyond,

the transparent substrate with the high-index medium has a TL (overall) of at least 70%, or even 80% and above, the network preferably having a transparent material.

In a first configuration, the first optical refractive index n1 of the substrate according to the invention may be less than or equal to 1.6, the high index medium is above the so-called low index substrate and is layer (s).

In a second configuration, the first optical refractive index n1 of the substrate according to the invention may be greater than or equal to 1.7, the high index medium then comprises the so-called high-index substrate, in particular made of mineral glass.

The high-index medium comprises a so-called bottom layer, which is transparent, in particular (substantially) continuous, directly on the internal face of the substrate, layer under the grating (preferably directly under the grating) and possibly between the low index patterns (on a fraction thickness or over the entire thickness), or even burying the grating, high index layer with a fifth refractive index n5 greater than or equal to 1.7.

The bottom layer (directly on the substrate) is of thickness between 50 nm and 1 μηη, depending on its functionality.

When used in particular for burying the pattern, a total thickness of at least 150 nm is preferably chosen and preferably adjusted according to the thickness of the optical guide, in particular the thickness of the organic electroluminescent system.

The transparent substrate with the transparent bottom layer (or even with the network and with the first electrode) may have a TL of at least 70%, or even 80% and beyond.

The index of the primer or any other layer of the high-index medium may be close to that of the first high-index electrode, with a difference preferably of less than 0.2.

The high-index medium may comprise a high-index base layer directly on the substrate and / or a high index layer under the network and on a bottom layer (high index or low index, directly on the substrate), chosen from:

an alkali barrier layer of the selected glass substrate, in particular of optionally doped Si ₃ N ₄ silicon nitride; silicon oxycarbide, silicon oxynitride, silicon oxycarbonitride, zinc oxide and tin, in particular of thickness between 5 and 1000 nm, or even less than 500 nm, or even 150 nm, of preferably between 20 and 150 nm including these values, and / or a layer, in particular of bottom, etching stop of the first electrode, in particular based on tin oxide Sn0 ₂ , Si ₃ N ₄ , in particular with a thickness between 5 and 300 nm, including these values. ,

and / or a particularly hydrophilic bottom layer on the chosen plastic substrate, a layer chosen from a layer of nitride, in particular silicon nitride, and / or an oxide layer, in particular made of titanium oxide, of zirconia,

and / or a bottom layer, only under the network, which is a smoothing layer of the underlying substrate is selected from

a layer (essentially) not crystallized into a single or mixed oxide, for example deposited under vacuum, in particular a layer based on mixed oxide based on zinc and tin (Sn _x Zn _y O _z or "ZTO"); ), based on mixed indium tin oxide (ITO), or mixed indium zinc oxide (IZO), thickness between 5 and 1000 nm, preferably thick less than or equal to 500 nm or even 150 nm,

a sol-gel layer, especially Zr0 ₂ , made of Ti0 _2, with a thickness of between 5 and 1000 nm, preferably with a thickness of less than or equal to 500 nm or even 150 nm,

and / or a vitreous base layer, for example made of molten glass frit, on the substrate chosen in mineral glass.

To bury the network in a simple manner, the high-index medium may comprise a layer (essentially) high index, especially transparent, deposited on and between the patterns, preferably over the entire height of the network layer that is a monolayer or a multilayer. The first electrode is for example on this high index layer (or has this layer). The first electrode may have an outer surface (farthest from the substrate) planarized. The first electrode may otherwise have an outer surface (furthest from the substrate), particularly corrugated, for example substantially conforming to the array of patterns, at least with a difference in heights between the so-called high surface above the patterns and the so-called surface. low between the patterns. The high index layer may be deposited by vapor deposition on the network, the first electrode deposited directly on this layer (or include this layer) without a planarization step.

To simply bury the network, the space between the patterns can be filled at least in part by the first electrode and the first electrode directly cover the network. The first electrode may have an outer surface (farthest from the substrate) planarized. The first electrode may otherwise have an outer surface (the most remote from the substrate), particularly corrugated, for example substantially in accordance with the pattern network, at least with a difference in height between the so-called high surface above the patterns and the so-called low surface between the patterns. This first electrode can thus be deposited by vapor deposition on the network and the organic layer deposited directly on the first electrode without a planarization step.

In order to simply bury the network, the high-index medium may comprise, under the network, a high-index monolayer possibly forming a primer.

Preferably the array is (substantially) inorganic, and / or the first electrode is (substantially) inorganic.

The first electrode may have an index (average) n3 between 1.8 to 2.2.

The first electrode may be in the form of a thin layer (s) deposited for example by deposition (s) in the vapor phase, in particular by magnetron sputtering, by evaporation.

The first electrode may comprise mainly (at least 80% electrode thickness), or even consist of a monolayer (continuous) based on at least one transparent conductive oxide, in particular chosen from zinc oxide doped in particular with aluminum (AZO) or gallium (GZO), based on mixed indium tin oxide (ITO) or based on mixed oxide of indium and zinc (IZO), mixed oxide indium, gallium and zinc (IGZO) in particular of thickness at least equal to 100 nm and less than 1500 nm, or even less than or equal to 500 nm.

The first electrode may also comprise a stack, essentially a high index, especially a transparent one, of layers (thin, continuous), in particular with a total thickness of less than 500 nm, or even less than 300 nm comprising in this order:

a first high-index sub-layer based on transparent conductive oxide, a first metallic functional layer with intrinsic properties of electrical conductivity, the functional layer being based on a pure material which is preferably silver, or based on said pure material alloyed or doped with another material chosen from: Ag Au, Pd, Al, Pt, Cu, Zn, Cd, In, Si, Zr, Mo, Ni, Cr, Mg, Mn, Co, Sn, especially of thickness between 3 and 20 nm, a high index overcoat based on transparent conductive oxide,

and optionally between the first metallic functional layer and the overlay at least once the following sequence:

a high index divider layer based on transparent conductive oxide,

another metallic functional layer. Naturally, the index (average) n3 of this stack with functional layer (s) metal (s) remains high index even with thin metal functional layers and any ultrafine metal layers under or overblocker.

An underlayer or overcoat layer of the functional layer (s) metal (s) contributes to improving the electrical performance of the first electrode (electrical conductivity and / or adaptation of the output work by different functions) :

growth sub-layer (or contact layer) for promoting the crystallinity of the metal layer,

- smoothing layer to reduce the electronic diffusion to the interfaces,

protective layer to external aggressions among which: ion bombardment during deposition of another layer, moisture, corrosion, migration of alkalis.

For the choices of the contact layer, a smoothing layer, a so-called on-blocker or under-blocker layer, reference may be made to patent applications WO 2008/029060 and WO 2008/059185 and WO 2009/083693.

Preferably, for reasons of cost, the total thickness of indium-containing material in the first electrode in the form of a stack of functional layer (s) metal (s) may be less than or equal to 60 nm preferably less than or equal to 50 nm. More generally, preferably the total thickness of indium-containing material in the high-index medium may be less than or equal to 60 nm, preferably less than or equal to 50 nm.

Preferably, to promote the injection of current and / or to limit the value of the operating voltage, the overlayer or the layer (s) separator (s) of the stack with functional layer (s) metal (s) has an electrical resistivity, solid state, less than or equal to 10 ⁷ ohm.cm, preferably less than or equal to 10 ⁶ ohm. cm, or even less than or equal to 10 ⁴ ohm. cm.

In particular, the stack with functional layer (s) (s) metal (s) may preferably be free of overlay thickness (total) greater than or equal to 15 nm or even greater than or equal to 10 nm or even 5 nm based on nitride silicon, silicon oxide, silicon oxynitride, silicon oxycarbide, based on silicon oxycarbonitride, or based on titanium oxide.

As already described, the first electrode may also comprise, for example, a metal layer, made of silver or aluminum and / or copper and with its planarization coating, this metallic layer being here discontinuous, in particular arranged in a grid, layer for example and is preferably manufactured without chemical or ionic etching step.

It can be manufactured in particular by masking as described in the patent application WO 2008/132397. For example, the same mask nature (in terms of the width of the openings and the size of the blocks of the mask if necessary) is used as for the mask serving to form the low index grating according to the invention.

Note that one can also choose to have a planarized electrode arranged in a high index grid as manufactured as described above, for example transparent conductive oxide (ITO, AZO ...).

For a better efficiency, the filling rate of the network, in other words the coverage rate (of the reasons) on the total surface covered by the network, can be between 1 and 40% by including these values, preferably between 3 and 20% including these values, or even between 5 and 15% by including these values, for example measured by contrast under the microscope (optical or electronic) on a reference surface, for example at least 300x300 μηη ² .

The patterns can be of any shape, including geometric, including having a substantially toothed section, rounded at the top.

The patterns can be one-dimensional (plots, ..) or two-dimensional: elongated patterns, curved or straight lines ...

As already indicated, the patterns can be disjoint (pins, spaced lines, etc.) and / or (partially) interconnected, especially in the form of a mesh (with possible mesh breaks), giving a network arranged in an aperiodic (random) grid, the distance B1 then being the intramalle distance.

Deposition of the low index material network can be done using conventional photolithography techniques. However, in an advantageous method according to the invention, the dimensions considered (patterns of width of the order of the visible wavelength, and preferably the filling rate of the substrate surface of about 15%) are all the same. makes it compatible with a process with a random mask. The benefits are many, including:

- low cost,

- non-periodic network (preventing diffraction effects).

Regarding the dimensions of the network:

the distance B1 may advantageously be less than 50 μηη, preferably less than or equal to 30 μηη or even less than or equal to 10 μηη, and even less than or equal to 6 μηη, and preferably with a distribution of distances between patterns defined by a standard deviation greater than 10% of the mean value, for example measurable by optical microscopy,

and preferably the maximum intermodal or intramotival aperiodic distance may advantageously be less than or equal to 100 μηη or even 50 μηη, and for example with an intramotif distance excluding a difference of more than 50% between a maximum distance along a first axis and a distance along a second oblique axis, in particular perpendicular,

and or

the average width A1 of patterns may be less than or equal to 5 μηη, or even less than or equal to 2 μηι, and preferably the width A1 is aperiodic with a distribution of widths A1 of the patterns defined by a standard deviation greater than 50% of the average value, for example measurable by optical microscopy,

and preferably the maximum pattern width of the array may advantageously be less than or equal to 10 μηη or even 5 μηη,

and or

the average (and preferably maximum) height of the patterns may be less than or equal to 300 nm, even less than or equal to 200 nm, or even less than or equal to 150 nm, in particular to limit electrical failures in the case of deposition of the first electrode on and between the units -, the average height is preferably greater than 50 nm, or even greater than or equal to 80 nm.

The dielectric network may comprise (or consists of) a layer of silica, in particular sol-gel, which preferably is a porous sol (gel) layer with an n1 less than or equal to 1, 5 or even less than or equal to 1, 4 even to less than or equal to 1, 3. The dielectric network may comprise (or consist of) a layer of CaF2,

A low structured index layer (for example by embossing, in particular of an optionally porous sol-gel silica layer) may be a carrier on the so-called external surface (surface opposite to the internal substrate face) of the network of low index patterns. Thus, this layer is of greater thickness than the height of the patterns, leaving a thick layer thickness underlying the network with a thickness of at most 40 nm or even 20 nm or even 10 nm or 5 nm and less than 1 nm. / 10 of the maximum height of the network.

Alternatively, the network, in particular silica (porous), is directly on a high-index sub-layer, in particular a high-index base layer, or directly on the selected high-index substrate. The transparent substrate may be a mineral glass in particular a so-called film thickness of between 20 μηη and 75 μηη including these values, for example a so-called ultrathin glass as proposed by Nippon Electric Glass and described in patent application JP2010132347. An industrial glass is preferably chosen, in particular silicates, preferably at low cost. It is preferably a silicosocalocalic glass.

The transparent substrate according to the invention can be a light flexible substrate. The substrate according to the invention may for example be or comprise a polymer film consisting of any transparent thermoplastic polymer of suitable properties. Examples of suitable thermoplastic polymers include, in particular, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate, polyurethane, polymethyl methacrylate, polyamides, polyimides, or fluoropolymers such as ethylene tetrafluoroethylene (ETFE), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE), ethylene chlorotrifluoroethylene (ECTFE), fluorinated ethylene-propylene copolymers (FEP), polyester, polyamide.

The support may comprise, above the first electrode, an organic electroluminescent system, in particular with a thickness of between 50 and 1000 nm, the organic electroluminescent system preferably emitting a polychromatic light, in particular white light.

On the first electrode are thus deposited (directly) the system with the organic layer (s) of the OLED high index or the organic electroluminescent layers between other organic layers.

The index n4 can be from 1, 8 or even beyond (1, 9 even more). The index n3 may be indifferently less than or equal to n4.

The OLED is emission from the bottom and possibly also from the top depending on whether the upper electrode (the second electrode) is reflective or respectively semi-reflective, or even transparent (in particular TL comparable to the first electrode typically from 60 % and preferably greater than or equal to 80%).

Advantageously, the grating having a given average height, the organic electroluminescent system and the high index medium (or optical medium) can form an optical guide of given thickness D1 (without excluding the possible thicknesses of low index layer (s). or the thicknesses of metal layers), the center of the grating, defined as half of the average height, is at a distance D2 from the surface farthest from the organic electroluminescent system substrate greater than or equal to 0.3 D1 ( counting the low layers index) or even higher or equal to 0.4 D1, and less than or equal to 0.7 D1 or even less than or equal to 0.6 D1, the second electrode (directly) on the organic electroluminescent system being for example reflective, metallic.

In a specific configuration, the organic electroluminescent system, the high-index medium (or optical medium) and a second high-index (semi-transparent) electrode (directly) on the organic electroluminescent system form an optical guide of given thickness D1, the medium of the network, defined as half of the average height, is at a distance D2 from the surface (external, furthest from the substrate) of the second electrode greater than or equal to 0.3 D1 or even greater than or equal to 0.4 D1, and less than or equal to 0.7 D1 or even less than or equal to 0.6 D1.

The network according to the invention being in the middle of the guiding high index structure, where the electric field is the most intense, it diffuses the rays very efficiently. The thinner the optical waveguide (especially with a low index substrate) the greater the electric field has a high intensity and the network is advantageously centered on this maximum to be the most effective.

Such a position guarantees better efficiency than with a network directly on the low index substrate or on a low index background layer because then this network is in an edge zone where the electric field is less intense.

In the case where the substrate is high index, the optical guide is relatively thick (even with an ultrathin substrate) the electric field is more spread and the network can be off-center without losing efficiency.

The carrier can be used as a carrier in an organic light-emitting diode device for illumination.

The organic light-emitting diode device, especially for lighting, may include the support.

As the grating has a given average height, the organic electroluminescent system according to the invention may be of thickness less than or equal to 250 nm, or even 150 nm, the thickness of the high index medium in the part underlying the grating is less than 200. nm, or even at 150 nm, the thickness of the first electrode is less than 200 nm, or even 100 nm, the average network height is at least equal to 50 nm or 100 nm and preferably less than 200 nm.

The organic electroluminescent system, in particular for illumination, may be of thickness greater than 250 nm, or even 400 nm and less than 1100 nm, the thickness of the high-index medium in the part underlying the network is less than 1100 nm. nm, or even 800 nm, the thickness of the first electrode overlying the network and a possible layer between the strands is greater than 250 nm or 400 nm and less than 1000 nm, the average network height is at least equal to 50 nm or 100 nm and preferably less than 200 nm.

The OLED system is preferably designed to emit a polychromatic radiation that can be defined at 0 ° by coordinates (x1, y1) in the CIE XYZ 1931 colorimetric chart, thus given coordinates for radiation to normal.

The OLED system may be preferably adapted to emit (substantially) white light, as close as possible to the coordinates (0.33, 0.33) or coordinates (0.45, 0.41), especially at 0 °.

To produce substantially white light several methods are possible including the following: mixture of compounds (emission red green, blue) in a single layer, stacking on the face of the electrodes of three organic structures (emission red green, blue) or two organic structures (yellow and blue).

The OLED can be arranged to produce a uniform polychromatic light, especially for uniform illumination, on a single area or to produce different light areas of the same intensity or distinct intensity.

The OLED can be part of a multiple glazing, including a vacuum glazing or with air knife or other gas. The device can also be monolithic, include a monolithic glazing to gain compactness and / or lightness.

The OLED can be glued or preferably laminated with another flat substrate said cover, preferably transparent such as a glass, using a lamination interlayer.

The OLED can form a lighting panel, or backlighting (substantially white and / or uniform) including surface (full) electrode greater than or equal to 1 x1 cm ² , or even up to 5x5 cm ² 10x10 cm ² and beyond.

Thus, the OLED can be designed to form a single illuminating pad (with a single electrode surface) in polychromatic light (substantially white) or a multitude of illuminating patches (with multiple electrode surfaces) in polychromatic light (substantially white ), each illuminating pad having a (full) electrode surface greater than or equal to 1 x1 cm ² , or even 5x5 cm ² , 10x10 cm ² and beyond.

The invention also relates to the various applications that can be found in these OLEDs, forming one or more transparent and / or reflecting luminous surfaces (mirror function) arranged both outside and inside.

The device can form (alternative or cumulative choice) an illuminating, decorative, architectural system, etc.), a signaling display panel - for example type design, logo, alphanumeric signage, including an emergency exit sign.

When the electrodes and the organic structure of the OLED are chosen to be transparent, an illuminating window can in particular be produced. Improved lighting of the room is not achieved at the expense of light transmission. By also limiting the light reflection, especially on the outside of the illuminating window, this also makes it possible to control the level of reflection, for example to comply with the anti-glare standards in force for the facades of buildings.

More generally, the device, in particular transparent by part (s) or entirely, can be:

- intended for the building, such as an external luminous glazing, an internal light partition or a part (part of) luminous glass door in particular sliding,

- intended for a transport vehicle, such as a bright roof, a (part of) side light window, an internal light partition of a land, water or air vehicle (car, truck train, airplane, boat, etc.) ,

- intended for street or professional furniture such as a bus shelter panel, a wall of a display, a jewelery display or a showcase, a wall of a greenhouse, an illuminating slab,

- intended for interior furnishing, an element of a shelf or furniture, a front of a piece of furniture, an illuminating slab, a ceiling lamp, a refrigerator lighting tablet, an aquarium wall,

- For the backlight of electronic equipment, including display screen or display, possibly dual screen, such as a TV screen or computer, a touch screen.

OLEDs are generally dissociated into two major families depending on the organic material used.

If the electroluminescent layers are small molecules, it is called SM-OLED ("Small Molecule Organic Light Emitting Diodes"). In general, the structure of an SM-OLED consists of a stack of hole injection layers or "HIL" for "Hole Injection Layer" in English, hole transport layer or "HTL" for "Hole Transporting" Layer "in English, emissive layer, electron transport layer or" ETL "for" Electron Transporting Layer "in English.

Examples of organic electroluminescent stacks are for example described in the document entitled "oven wavelength white organic light emitting diodes" using 4, 4'-bis- [carbazoyl- (9)] - stilbene as a deep blue emissive layer "from CH. Jeong et al., Published in Organics Electronics 8 (2007) pages 683-689.

If the organic electroluminescent layers are polymers, it is called PLED ("Polymer Light Emitting Diodes" in English).

The organic layer stack of an OLED device therefore comprises at least one organic electroluminescent core layer for producing a light, preferably white, interposed between an electron transport layer and a hole transport layer, same intercalated between an electron injection layer and a hole injection layer.

There are OLED devices comprising a heavily doped "HTL" (Hole Transport Layer) layer as described in US7274141 and for which the last layer of the first electrode does not necessarily have the function of adapting the output work.

There are OLEDS systems of thickness between 100 and 500 nm, typically 350 nm or thicker OLED systems for example 800 nm as described in the article entitled "Novaled PIN OLED® Technology for High Performance OLED Lighting" by Philip Wellmann, related to the Lighting Korea conference, 2009.

The second electrode of the OLED, or upper electrode or generally cathode, is of electrically conductive material and preferably (semi) reflective, in particular a metallic material of the silver or aluminum type.

Each of the layers of the high-index medium is preferably of low absorbency, especially of visible absorption less than 10 ^-2 cm ^-1 .

Preferably, the high-index medium may comprise even consist of essentially inorganic or hybrid (inorganic organic) layers.

The invention also relates to a method for manufacturing the organic light-emitting diode device support as defined above and which comprises:

supplying the high-index transparent substrate or the low-index transparent substrate with at least one high-index layer of said high-index medium, in particular a base coat,

before the complete formation of the first electrode in the case where the electrode is partly under the network, or before the formation of the first electrode in the case where the electrode (directly or otherwise) on the network (and possibly between the patterns), the formation of the dielectric network of low-indexed patterns with layer (s) with the random distance B1, without photolithography step (s) or etching (ionic or chemical), - In particular to (complete) burying the network in the high index medium, the deposition (of at least one high index layer (preferably non-selective deposition that is to say between the patterns and patterns).

The invention also relates to a method of manufacturing the organic electroluminescent diode device support as defined above, the formation of the low index pattern dielectric network with a random distance B1 comprises:

the deposition on the high-index substrate or on a layer (low index or high index of the high-index medium), in particular of the high-index base layer, of a liquid masking layer (in particular an insurable gel-sol layer, for example silica),

drying the masking layer until a mask with interstices is obtained with a distance B between random interstices substantially equal to the random distance B1 of the patterns of the grating (desired),

depositing through the interstices of the mask and preferably on the layer mask (s) made of material (x) of the low index pattern network until at least a fraction of the depth of the interstices is filled,

- removal of the mask, until revealing the dielectric pattern of low index patterns.

The invention also relates to a method of manufacturing the support of the organic light-emitting diode device as defined as follows:

the liquid deposit is a deposit of a solution of colloidal particles stabilized and dispersed in a solvent,

the particles having a given glass transition temperature Tg, the deposition and the drying of the mask are implemented at a temperature below said temperature Tg, in particular forming a mesh with a substantially straight edge, in particular a two-dimensional network of interstices,

the deposition through the interstices of layer (s), in particular silica, of the low index pattern network, is in the gaseous phase,

- The removal of the mask is preferably by liquid.

After drying, clusters of nanoparticles, clusters of variable size and separated by the interstices themselves of varying sizes, are thus obtained.

To obtain the openings over the entire depth, it is necessary at a time:

to choose particles of limited size (nanoparticles), to promote their dispersion, with preferably a characteristic (average) dimension between 10 and 300 nm including these values, or even between 50 and 150 nm including these values,

to stabilize the particles in the solvent (in particular by treatment with surface charges, for example by a surfactant, by controlling the pH), in order to prevent them from aggregating with each other, precipitating them and / or they do not fall by gravity.

In addition, the (total) concentration of particles is adjusted, preferably between 5% and 50% by volume, including these values, or even between 10% and 50% by volume, including these values, even more preferably between 20% and 40% by volume. including these values. In case of mixing of particles, the solution has a volume concentration of at least 80% of particles of Tg higher than the drying temperature.

The difference between the given glass transition temperature Tg of the particles and the drying temperature is preferably greater than 10 ° C. or even 20 ° C.

The invention also relates to a method for manufacturing the organic light-emitting diode device as defined above, the mask of which has a thickness of less than 5 μηη, preferably less than or equal to 3 μηη, in particular between 0.5 and 3 μηη, including those values, and before the deposition of layer (s) of the low index pattern network, the mask is brought to a temperature greater than or equal to 0.8 times Tg, thus widening the interstices up to an average width A1 less than or equal to 5 μηη or less than or equal to 2 μηη and a mean distance B1 less than or equal to 10 μηη or even less than or equal to 6 μηη.

For such a rather thin mask (and with narrow gaps), it is preferable to sufficiently dilute the colloidal solution in water, to have a (total) concentration of particles less than or equal to 35%. This greatly reduces the size of the cracks which are then sufficiently enlarged by the high temperature experienced by the mask (annealing for example) producing compaction of the mask.

The invention also relates to a method for manufacturing the organic light-emitting diode device whose substrate is made of glass and whose formation of the sol-silica gel network comprises the following steps:

the provision of a precursor sol of the material constituting the silica layer, in particular a hydrolysable compound such as a silicon alkoxide, in a particularly aqueous and / or alcoholic solvent, optionally mixed with a pore-forming agent,

depositing a layer of said silica sol,

a possible stage of solvent removal, - An embossing (partial, until an underlying thickness less than 40 nm or 20 nm or even 10 or 5 nm, or preferably complete) of the layer with a mask bearing patterns complementary to said low index pattern.

This silica gel sol layer may be porous and obtained by elimination of a particularly solid pore-forming agent, the process comprising, after embossing, the formation of the low-index pattern network in porous silica gel sol, by said elimination of pore-forming agent by means of a heat treatment, in particular from 350 ° C. or even 500 ° C., or even 600 ° C. followed preferably by a quenching (thermal) operation.

The embossing may preferably be carried out at a temperature of between 65 ° C. and 150 ° C., preferably between 100 ° C. and 120 ° C., in particular for silane-based gel sols, in particular TEOS.

The surface can be sufficiently hardened before separation of the mask and the product.

Also, the pattern is for example preferably stiffened (or at least begins to stiffen) during contact and / or after contact, by at least one of the following treatments: heat treatment, radiative, by exposure to an atmosphere controlled treatment (s) modifying the mechanical properties of the surface.

The present invention is now described by way of purely illustrative and non-limiting examples of the scope of the invention, and from the attached illustrations, in which

FIG. 1 represents a schematic sectional view of a support for OLED according to the invention in a first embodiment,

FIGS. 2a and 2b represent, in plan view, the mask of the low patterned network index of a support for OLED according to the invention, in the form of an image obtained by microscopy and a layer of this image,

FIGS. 3a to 4b each show, in plan view, the low pattern dielectric network index of an OLED support according to the invention, in the form of images obtained by microscopy and layers of these images,

FIG. 5 is a diagrammatic plan view of another low pattern network indexing a support for OLED according to the invention.

FIG. 1, which is not to scale for a better understanding, schematically shows in sectional view a support 10 for an organic light-emitting diode device 100 in a first configuration which successively comprises: a low-index transparent substrate 1, for example plastic (preferably PET or PEN with a thickness of 50 to 250 μηη) or "low-index" glass (in particular soda-lime glass, with a thickness of 0.7 mm to 3 mm or a film glass), which comprises on a first main face in this order, - a high index medium 10 burying a low index network 3 successively comprising:

a base layer 2 deposited directly on the substrate, a high index layer, transparent and (substantially) continuous, with a refractive index n5 greater than or equal to 1.7,

- any other high index layers (not shown),

a dielectric network 3 of low-index units 30 with a second optical refractive index n2 of less than or equal to 1, 6, network having a distance between motifs or intra-aperiodic patterns B1 and a width of patterns A1, the patterns being 1 D or 2D, disjoint or joined, for example interconnected and forming an irregular grid,

- Between the aperiodic network 3 and on the network, a first transparent electrode in the form of a first electroconductive coating 4, which is the anode, with an optical refractive index n3 greater than or equal to 1.7.

The high-index base layer 2 may be in S _i3 N ₄ deposited by magnetron sputtering, more precisely deposited by reactive sputtering using an aluminum-doped silicon target, at a pressure of 0.25 Pa in an argon / nitrogen atmosphere. Its thickness is for example 100 nm.

The bottom layer covers the substrate (near the apargage) and also serves:

- alkaline barrier in the case of glass,

and / or hydrophilic layer in the case of plastic,

stopping etching during etching, especially acidic, of the first electrode. High-index layers, especially transparent, can be arranged under the network, on the bottom layer, or even between the patterns, are for example AlN, TCO such as SnZnO, ZnO, ITO, TiO ₂ , ZrO 2 with or without presence of doping elements.

The low index network is for example a SiO ₂ silica layer and preferably a porous silica (sol-gel) layer for lowering the refractive index.

The first electrode 4, preferably the anode, comprises, for example, a high-index transparent electro-conductive coating such as tin-doped indium oxide (ITO) or a silver stack.

Money stacking includes: a possible zinc-tin mixed oxide underlayer optionally doped or a tin-indium mixed oxide (ITO) layer or a mixed indium-zinc oxide layer ( IZO)

a metal oxide-based contact layer chosen from ZnO _x doped or non-doped, Sn _y Zn _z O _x , ITO or IZO,

a functional metallic layer, for example silver, with intrinsic property of electrical conductivity,

a possible thin layer of overblocking directly on the functional layer, the thin layer of overblocking comprising a metal layer of thickness less than or equal to 5 nm and / or a layer with a thickness less than or equal to 10 nm which is based on stoichiometric metal oxide, stoichiometric metal oxynitride or stoichiometric metal nitride (and optionally a thin layer of under-blocking directly under the functional layer),

a metal oxide-based overcoat, for example for adjusting the output work.

On the possible bottom layers and / or wet etch stop layer and / or under layers is arranged n times the following structure, with n an integer greater than or equal to 1 (in particular n = 2 is a bilayer at least 1). money) :

- the contact layer,

- possibly a thin layer of under blocking,

the functional layer,

- the thin layer of overblocking.

The final layer remains the overlay.

It is thus possible to mention a silver stack for example as described in documents WO2008 / 029060 and WO2008 / 059185 or WO2009 / 083693.

Table 1 below summarizes the nature and the geometric thickness in nanometers of the various examples of silver bilayer stacks and a monolayer silver stack, as well as their main optical and electrical characteristics. Examples of first No. 1 No. 2 No. 3 No. 4 No. 5 electrode

Layers / e (nm)

SnZn: SbO _x 5 7 4 6 5

ZnO: AI 5 3 6 4 5

Ag 8 9 1 1 9 12

Ti 0.5 <1 <1 <1 0.5

ZnO: AI 5 5 5 5

SnZn: SbO _x 60 46 49 39

ZnO: AI 5 5 5 5

Ag 8 8 8 8

Ti 0.5 <1 <1 <1

ITO 20 22 18 32 10

properties

Thickness of the electrode

(nm) 1 17 105 106 106 32

R per square of 2.7 2,6 2,4 2,6 3,5 the electrode (Ω / square)

Table 1

The deposition conditions for each of the layers of the first electrode (anode) are as follows:

the layers based on SnZn: SbO _x are deposited by reactive sputtering using a target of zinc and antimony-doped tin containing by mass 65% Sn, 34% Zn and 1% of Sb, under a pressure of 0.2 Pa and in an argon / oxygen atmosphere,

the silver-based layers are deposited using a silver target, under a pressure of 0.8 Pa in a pure argon atmosphere,

the Ti layers are deposited using a titanium target under a pressure of 0.8 Pa in a pure argon atmosphere,

the ZnO: Al layers are deposited by reactive sputtering using an aluminum doped zinc target at a pressure of 0.2 Pa and in an argon / oxygen atmosphere, the ITO-based overcoats are deposited using a ceramic target in an argon / oxygen atmosphere at a pressure of 0.2 Pa and in an argon / oxygen atmosphere.

The first electrode may alternatively comprise an underlying blocking coating, comprising, in particular, as the overlying locking coating, a metal layer preferably obtained by a metal target with a neutral plasma or nitride and / or oxide of one or more metals such as Ti, Ni, Cr, preferably obtained by a ceramic target with a neutral plasma.

To form the OLED is then added (not shown), an electroluminescent system with organic material (s), having an optical refractive index n4 greater than or equal to 1.7, for example directly on the first electrode, without step planarization.

A second electrode is then produced in the organic system in the form of a second electro-conductive coating (not shown) which is reflective and intended to reflect the light emitted by the organic system to the opposite direction, that of the transparent substrate 1 from which light (top emission).

The high index medium supplemented by the electroluminescent system with organic material (s) forms a high index optical guide 100 with a given thickness D1 (outside the thickness of the network naturally), including the possible metal grid of the gate electrode or any metal layers of a layer stack electrode).

The thicknesses are preferably chosen so that the low index network is placed sufficiently close to the center of the high index waveguide.

In the configuration of Figure 1 (network on the base layer, first electrode between the network and directly covering the network), with the thicknesses

of 100 nm for the high-index primer, in particular Si ₃ N ₄ ,

about 100 nm of the first high-index electrode (multilayer stack with silver for example),

100 nm of the organic stack of average index 1, 8,

- and the network of height 80 nm,

the thickness D1 of the guide is approximately 300 nm, the center of the grating (at 40 nm) is optimally centered in the waveguide at a distance D2 (counting the low index, metal layers) of 140 nm the outer surface of the guide (surface of the organic system).

In the case of a thick OLED, that is to say where the organic stack with the first electrode is several hundred nm (especially because of a thickness HTL layer important to limit the sensitivity to electrical faults), it is necessary to increase the thickness of the primer.

In the configuration of Figure 1 (network on the bottom layer, first electrode between the network and directly covering the network), with the thicknesses:

800 nm for the primer, in particular SI ₃ N ₄ ,

about 150 nm from the first electrode, in particular from ITO,

650 nm of the organic stack of average index 1, 8,

- and the 80 nm height network

the guide thickness D1 is about 1600 nm, the center of the grating (at 40 nm) is optimally centered in the waveguide at a distance D2 of 760 nm (counting the low index layers) of the surface external guide (organic system surface).

800 nm for the primer, in particular SI ₃ N ₄ ,

about 100 nm from the first electrode, in particular multilayer stack with silver,

800 nm of the organic stack of average index 1, 8,

- and the 80 nm height network

the guide thickness D1 is about 1700 nm, the center of the grating (at 40 nm) is optimally centered in the waveguide at a distance D2 of 860 nm (counting the low index layers) of the surface external guide (organic system surface).

If in the first variant, a second high-index electrode (TCO, etc.) is chosen, especially in ITO (for example 100-150 nm thick), the optical waveguide comprises this second electrode and its thickness must be included in the thickness in D1 and in the evaluation of D2.

In a first variant not shown, the glass is high index and for example the grating is deposited directly on the glass or on a high-grade base coat. The network does not have to be centered in the waveguide to be the most efficient.

In a second variant not shown, a layer of SI ₃ N ₄ is deposited directly between the patterns and on the low index network between and on the patterns 30, the first electrode 4 is then deposited directly on this high index layer. The first electrode can then be a stack as already described or a metal grid planarized by a high index coating for example obtained by depositing on a cracked mask or a TCO layer.

In the configuration of this second variant (network on the base layer, layer in recovery between the network and directly covering the network and first electrode above), with the thicknesses:

of 100 nm for the high base layer index 2, SI ₃ N ₄ ,

about 100 nm of the recovery layer of SI ₃ N ₄ ,

about 20 nm from the first high-index electrode 4 (monolayer stack with silver for example),

100 nm of the organic stack 5 of average index 1, 8,

- and the network of height 80 nm,

the guide thickness D1 is about 320 nm, the center of the grating (at 40 nm) is optimally centered in the waveguide at a distance D2 of 160 nm from the outer surface of the guide (surface of the organic system ).

More detailed examples of fabrication of the low index dielectric array follow.

MANUFACTURING EXAMPLE 1 - Step No. 1 for depositing a mask

On a high-index layer (preferably the primer layer) or on a substrate, in particular high-grade mineral glass, a "wet coating technique" is a mixture of two solutions of two types of colloidal particles. Acrylic copolymer base stabilized in water.

The first solution contains first colloidal particles having a characteristic dimension of between 80 and 100 nm and are marketed by the company DSM under the trademark Neocryl XK 52® and have a glass transition temperature Tg1 equal to 1 15 ° C. and are diluted to 40% in water.

The second solution contains second colloidal particles having a characteristic dimension of 190 nm and are marketed by the company

DSM under the trademark Neocryl XK 240® and have a glass transition temperature Tg2 of less than 30 ° C and are diluted 52% in water.

It is the first particles ("hard") that make the mask Assurable by choosing a drying less than Tg1 preferably the ambient temperature.

The second particles contribute to the adhesion of the mask on the substrate or the underlying layer.

We choose to mix 97 volumes of the first solution with 3 volumes of the second solution. The total concentration of particles in the mixture of the two solutions is about 40% by volume and the mixture has a volume concentration of more than 95% of the first particles. The thickness of the mask is 8 to 10 μηι.

The layer incorporating the colloidal particles is then dried so as to evaporate the solvent and form the interstices. This drying can be carried out by any suitable method and preferably at a temperature below Tg (hot air drying, etc.), for example at room temperature.

During this drying step the system self-arranges according to an irregular arrangement. A stable mask is obtained without annealing.

A two-dimensional network of closed-edge gaps is created surrounding blocks of variable size.

The mask has a variable width, aperiodic interstices between 1, 5 and 5.7 μηι, and a variable, aperiodic length of a block between 15 and 65 μηι.

The length-to-width ratio can also be modified by adapting, for example, the coefficient of friction between the compacted colloids and the surface of the primer layer, or the size of the nanoparticles, or even the rate of evaporation, or the initial concentration of particles, or the nature of the solvent, or the thickness depending on the deposition technique ...

In a second embodiment, a mixture is deposited:

a first solution of silica colloids with a characteristic dimension of less than 10 nm, for example the product TMA sold by the company Aldrich diluted to 40% in water and Tg greater than 1000 ° C .;

a second solution of polyacrylamide dissolved at 30% in water.

The total concentration of particles in the mixture of solutions is about 36% by volume. One chooses to mix 90 volumes of the first solution with 10 volumes of the second solution.

The thickness of the mask is about 5 μηη. The mask has a variable width, aperiodic interstices between 1 and 2 μηη, and a variable, aperiodic length of a block between 15 and 35 μηη.

A two-dimensional network of interstices 31 with a closed contour surrounding blocks 32 of variable size is obtained. Figures 2a and 2b show such a mask.

In a third embodiment, the mixture of the two solutions already described for the first example is deposited. It is still chosen to mix 97 volumes of the first solution with 3 volumes of the second solution, but by diluting with water so that the total concentration of particles in the mixture drops to about 30% by volume. The mixture retains a volume concentration of more than 95% of the first particles. The thickness of the mask is limited to about 2.5 μηη.

Thereafter a heat treatment (15 min at 140 ° C in an oven under air) of the mask dry and cracked to widen the cracks.

The mask then has a variable width, aperiodic interstices between 0.5 μηη and 1 μηη and a variable, aperiodic length of a block between 3 and 8 μηι.

A morphological study of the mask (in all the examples above) showed that the interstices have a right crack profile.

The crack profile has a definite advantage for:

deposit, in particular in a single step, a large thickness of material,

- Keep a pattern, particularly thick, consistent with the mask after removing it.

Step 2 of deposition of material (x) of the low-indexed dielectric pattern

The material of the low-index pattern network is deposited through the mask until a fraction of the interstices are filled.

This deposition phase can be carried out by gas phase deposition, for example by magnetron sputtering. The material is deposited on the mask and inside the interstitial network in order to fill the cracks, the filling being carried out at least in a fraction of the thickness of the interstices network.

It is thus chosen to deposit silica by magnetron sputtering with a thickness of 30 nm to 200 nm, preferably around 80 to 100 nm. A low index dielectric array is formed, with an average aperiodic width of the A1 patterns and an average aperiodic distance B1 similar to the mask dimensions.

Step 3 of revealing the low-indexed dielectric pattern

In order to reveal the grid structure from the mask, a "lift off" operation is performed. This operation is facilitated by the fact that the cohesion of the colloids results from weak forces, Van der Waals type (no binder or bonding resulting by annealing). The colloidal mask is then immersed in a solution containing water and acetone (the cleaning solution is chosen according to the nature of the colloidal particles) and then rinsed so as to remove all the parts coated with colloids. We can accelerate the phenomenon through the use of ultrasound to degrade the mask of colloidal particles and reveal the complementary parts (the network of interstices filled by the material) that will conform the grid.

FIGS. 3a to 4b show the two morphologies in top view of the low index pattern dielectric network obtained with the last two masks described above (second and third embodiments).

The grating obtained according to the third embodiment (FIGS. 4a and 4b) is denser and is preferred. - Step No. 4 deposition of material (x) of the first electrode

For the configuration of FIG. 1, the first electrode - for example a multilayer stack with silver already described - is deposited between the patterns and on the patterns of the low index grating.

The low index grating is not affected by the deposition of the first electrode, and furthermore the gap of the first electrode is similar to that on a planar substrate.

For an alternative configuration, a layer is deposited in recovery of the material of the bottom layer. Then the first electrode is deposited, for example identical to that described for the first configuration. EXAMPLE 2 OF MANUFACTURE

In another example, the pattern low-index network is a porous silica sol-gel layer, and is embossed.

The sol-gel silica-based layer is obtained with a TEOS or MTEOS precursor and rendered porous by removal of a pore-forming agent.

It is thus possible to lower the refractive index of the material below 1, 5 or even 1, 3, which increases the index contrast and thus the luminous diffusion efficiency.

The first step consists, as in the previous example, in depositing a 100 nm layer of Si ₃ N ₄ , for example by sputtering onto a glass substrate.

The production of a sol-gel-type porous layer on the base layer firstly comprises the following successive steps:

the preparation of a precursor sol of the material constituting the silica layer, in particular a hydrolysable compound such as a halide or a silicon alkoxide, in a particularly aqueous and / or alcoholic solvent, the mixture with a pore-forming agent, in particular solid in the form of particles, the particles preferably being greater than or equal to 20 nm, in particular between 40 and 100 nm,

- The deposit of the mixture on the bottom layer.

The solid pore-forming agent may advantageously comprise beads, preferably polymeric, in particular of the PMMA type, methyl methacrylate / acrylic acid copolymer or polystyrene.

The deposition on the substrate can be carried out by spraying, by immersion and drawing from the silica sol (or "dip coating"), by centrifugation (or "spin coating"), by casting ("flow-coating"), by roll ("roll coating").

The pattern of the low index grating is then defined by embossing the deposited layer with a carrier pad of patterns complementary to said desired low index patterns. The method of embossing a sol-gel layer is conventional.

The layer is then subjected to a heat treatment at least 500 ° C, or even at least 600 ° C for a period of preferably less than or equal to 15 minutes, or even 5 minutes followed by quenching. It allows on the one hand to cook the textured layer, and on the other hand to evaporate the organic nanoparticles, in order to lower the index of refraction of the low index network.

As an example of a porous sol-gel layer, reference may be made to the layers described in the patent application WO 2008/059170 (examples of this application with an oil or particulate porogen or given examples of the prior art with a conventional porogen ).

FIG. 5 schematically shows an example of a low index grating 3 formed of studs randomly distributed and of variable size, a grating formed for example by embossing a sol-gel silica layer.

Claims

Support (10) for an organic light-emitting diode device (1000) comprising:

a transparent substrate (1) of first optical refractive index n1 given with a first so-called internal main face and a second so-called external main face, the internal face comprising:

- A dielectric network (3), in the form of layer (s) arranged in a discontinuous manner and thus a set of patterns (30), said low index, the network having a second optical refractive index n2 less than or equal to 1, 6, the low-index patterns being of submicron height, of average width A1 of patterns less than or equal to 6 μηη, and the patterns being disjoint and the adjacent patterns then spaced by a given intermotive distance and / or the patterns being interconnected, in particular in grid, with a given intramotifs distance, the distance B1, which is the average of the intermotifs and / or intramotifs distances, being micron greater than the width A1 and less than or equal to 50 μηι,

a first electrode (4), in particular transparent, in the form of a layer (s), with a given third optical refractive index n3 greater than or equal to 1.7, the first electrode having a square resistance of less than 30 ohms per square,

characterized in that

the distance B1 is aperiodic,

at least a fraction of the thickness of the first electrode (4) is above said grating (3), and is in contact with the surface of the grating (3) farthest from the substrate (1) or is spaced from the grating (3) low index patterns,

- The network (3) is buried in a high index medium (100), the network thus being inside the high index medium, the high index medium comprising the first electrode (4) as a layer (s) further away from the substrate, the high index medium having a fourth refractive index n4 greater than or equal to 1.7.

Support (10) for an organic light-emitting diode device (1000) according to Claim 1, characterized in that the first optical refractive index n1 of the substrate (1) is less than or equal to 1.6, the high-index medium (100) is above the substrate (1) said low index and is layer (s). Support for organic electroluminescent diode device according to claim 1 characterized in that the first optical refractive index n1 of the substrate is greater than or equal to 1.7, the high index medium comprises the so-called high-index substrate, in particular mineral glass.

Support (10) for an organic light-emitting diode device (1000) according to one of the preceding claims, characterized in that the high index medium (100) comprises a so-called transparent bottom layer (2), directly on the internal face of the substrate, layer under the grating (3) and possibly between the low index patterns, or even burying the grating, high index bottom layer with a fifth refractive index n5 greater than or equal to 1.7.

Support (10) for an organic light-emitting diode device (1000) according to one of the preceding claims, characterized in that a low structured index layer is a carrier on the so-called external surface, opposite to the internal substrate face, of the low index pattern network. , the layer thus having a thickness greater than the height of the patterns, leaving a thickness of the solid layer underlying the network of thickness at most less than 40 nm or even 20 nm and less than 1/10 of the maximum height of the network .

Support (10) for an organic light-emitting diode device (1000) according to one of Claims 1 to 4, characterized in that the grating is directly on a high-index layer, in particular a high-index base layer, or directly on the selected substrate. index.

Support (10) for an organic light-emitting diode device (1000) according to one of the preceding claims, characterized in that the high-index medium (100) comprises a high-index base layer (2) directly on the internal face of the substrate and / or under the network or comprises a high index layer under the network and on a bottom layer, high index layer chosen from:

a particularly alkaline barrier layer (2) of the chosen glass substrate, in particular of optionally doped silicon nitride, of silicon oxycarbide, of silicon oxynitride, of silicon oxycarbonitride, of zinc oxide, and tin,

and / or a layer, in particular of bottom, etching stop (2) of the first electrode (4) in particular based on tin oxide, silicon nitride,

and / or a layer, particularly of a high hydrophilic index, on the selected plastic substrate, a bottom layer chosen from a layer of nitride, in particular of silicon nitride, and / or an oxide layer, especially of titanium oxide, of zirconia,

and / or a bottom layer only under the network which is a smoothing layer of the underlying substrate, which is chosen from:

a non-crystallized layer made of a single or mixed oxide, in particular chosen from a mixed oxide based on zinc and tin, based on a mixed oxide of indium and tin, or based on a mixed oxide; indium and zinc,

a sol-gel layer, especially Zr0 ₂ ; in Ti0 _2,

and / or a high-index vitreous base layer, for example made of molten glass frit, on the chosen substrate made of mineral glass.

Support (10) for an organic light-emitting diode device (1000) according to one of the preceding claims, characterized in that the high index medium comprises a high index layer (4), in particular transparent, deposited on and between the patterns, preferably on the entire height of the network.

Support (10) for an organic light-emitting diode device (1000) according to one of the preceding claims, characterized in that the space between the patterns (30) is filled at least in part by the first electrode (4) and the first electrode directly covers the network.

Support (10) for an organic light-emitting diode device (1000) according to one of the preceding claims, characterized in that the first electrode (4) comprises:

mainly a high-index monolayer based on at least one conductive transparent oxide, in particular chosen from aluminum-doped zinc oxide, based on mixed indium-tin oxide or based on a mixed oxide of indium and zinc, in particular having a thickness of at least 100 nm and less than 1500 nm,

and / or an essentially high index stack (4), in particular transparent, of layers comprising in this order:

a first high-index sub-layer based on transparent conductive oxide,

a first functional metallic layer with intrinsic properties of electrical conductivity, the functional layer being based on a pure material which is preferably silver, or based on said pure material alloyed or doped with another material chosen from: Ag , Au, Pd, Al, Pt, Cu, Zn, Cd, In, Si, Zr, Mo, Ni, Cr, Mg, Mn, Co, Sn, a high-index overcoat based on transparent conductive oxide,

a high index divider layer based on transparent conductive oxide; another metallic functional layer.

1 1. Support (10) for an organic light-emitting diode device (1000) according to one of the preceding claims, characterized in that the filling rate of the network (3) is between 1 and 40% by including these values, preferably between 3 and 20 % including these values.

12. Support (10) for an organic light-emitting diode device (1000) according to one of the preceding claims, characterized in that the average height of the patterns (30) is less than or equal to 300 nm, or even less than or equal to 200 nm, and the average height is preferably greater than 50 nm.

13. Support (10) for organic light-emitting diode device (1000) according to one of the preceding claims characterized in that the distance B1 is less than or equal to 30 μηη or less than or equal to 10 μηη, preferably with a distribution of distances defined by a standard deviation greater than 10% of the average value and in that preferably the maximum aperiodic distance between patterns of the network (3) is less than or equal to 100 μηη.

14. Support (10) for an organic light-emitting diode device (1000) according to one of the preceding claims, characterized in that the average width A1 of patterns (30) is less than or equal to 5 μηη, or even less than or equal to 2 μηη, and preferably the width A1 is aperiodic with a pattern width distribution defined by a standard deviation greater than 50% of the average value and in that preferably the maximum pattern width of the network is less than or equal to 10 μηη, even at 5 μηι.

15. Support (10) for an organic light-emitting diode device (1000) according to one of the preceding claims characterized in that the network is inorganic, and in particular comprises a layer of CaF2 or a layer of silica (3), in particular sol- gel, which is preferably a porous layer with the index n1 less than or equal to 1, 5 or even less than or equal to 1, 4.

16. Support (10) for an organic light-emitting diode device (1000) according to one of the preceding claims, characterized in that the substrate (1) is made of mineral glass, in particular a so-called film pellicle thickness between 20 μηη and 75 μηη including these values or that the substrate is plastic.

17. Support (10) for organic light-emitting diode device (1000) according to one of the preceding claims characterized in that the high-index medium (100) consists of essentially inorganic layers.

18. Support (10) for organic light-emitting diode device (1000) according to one of the preceding claims characterized in that it comprises above the first electrode (4) an organic electroluminescent system (5), including thickness between 50 and 1000 nm, the organic electroluminescent system preferably emitting a polychromatic light, in particular white.

19. Support (10) for organic light-emitting diode device (1000) according to the preceding claim characterized in that the network having a given average height, the organic electroluminescent system (5) and the high-index medium form an optical guide (1 10 ) of given thickness D1, the center of the grating (3), defined as half of the average height of the grating, is at a distance D2 from the farthest surface of the organic electroluminescent system substrate (5) which is greater than or equal to equal to 0.3 D1 or even greater than or equal to 0.4 D1, and less than or equal to 0.7 D1 or even less than or equal to 0.6 D1, the second electrode on the organic electroluminescent system being reflective, in particular metallic,

or in that, the organic electroluminescent system (5), the high index medium and a second high index electrode on the organic electroluminescent system form an optical guide of given thickness D1, the middle of the network (3), defined as half the average height of the network, is at a distance D2 from the surface of the second electrode greater than or equal to 0.3 D1 or even greater than or equal to 0.4 D1, and less than or equal to 0.7 D1 or less than or equal to 0.6 D1.

20. An organic electroluminescent diode device (1000), particularly for illumination, including the support (10) according to any of the preceding support claims.

21. An organic light-emitting diode device (1000), according to claim 20, characterized in that the organic electroluminescent system (5) is less than or equal to 250 nm thick of the high index medium (1 10) in the sub-part. underlying the network (2) is less than 200 nm, the thickness of the first electrode (4) is less than 200 nm, the average network height is at least equal to 50 nm and preferably less than 200 nm. An organic light-emitting diode device, especially for illumination, according to claim 20, characterized in that the organic electroluminescent system is greater than 250 nm, or even 400 nm and less than 1100 nm, the thickness of the medium high. index in the underlying part of the network is less than H OO nrm, the thickness of the first electrode overlying the network and a possible layer between the strands is greater than 250 nm and less than 1000 nm, the height average of the network is at least 50 nm and preferably less than 200 nm.

A method of manufacturing the organic light-emitting diode device carrier (10) (1000) according to one of the preceding support claims, characterized in that it comprises:

supplying the high-index transparent substrate or the low-index transparent substrate (1) with at least one high-index layer (2) of said high-index medium (100), in particular a basecoat,

before the complete formation of the first electrode (3) in the case where the electrode is partly under the network, or before the formation of the first electrode (3) in the case where the electrode is on the network, the formation of the low-index dielectric pattern grating with layer (s) (3) with the random distance B1, without photolithography or etching step.

A method of manufacturing the organic light-emitting diode device carrier (1000) according to the preceding method claim characterized in that forming the low-index pattern dielectric array (3) with a random distance B1 comprises:

the deposition on the high-index substrate or on a layer (2) of the high-index medium (100), in particular a high-index base layer, of a liquid masking layer,

- drying the masking layer until a mask with gaps (31) with a distance B between random interstices substantially equal to the random distance B1 patterns (30) of the network (3),

depositing through the interstices (31) of the layer mask (s) made of material (x) of the low index pattern network until at least a fraction of the depth of the interstices is filled,

- The removal of the mask, until revealing the dielectric network (3) of low index patterns (30). A method of manufacturing the support of the organic light-emitting diode device (1000) according to the preceding method claim characterized in that:

the particles having a given glass transition temperature Tg, the deposition and drying of the mask are carried out at a temperature below said temperature Tg,

the deposition through the interstices of the layer (s) of the low index pattern network is in a gaseous phase

removal of the mask is preferably liquid.

A method of manufacturing the organic light-emitting diode device (1000) according to the preceding method claim characterized in that the mask has a thickness less than 5 μηι, preferably less than or equal to 3 μηι, and in that, before the deposit of layer (s) of the low index pattern network, the mask is brought to a temperature greater than or equal to 0.8 times Tg, thus widening the interstices up to an average width A1 less than or equal to 5 μηη or even less than or equal to 2 μηι and a mean distance B1 less than or equal to 10 μηη or even less than or equal to 6 μηη.

A method of manufacturing the organic light-emitting diode device (1000) according to claim 23, characterized in that the substrate is made of glass and in that the formation of the selected sol-gel silica network comprises the following steps:

providing a precursor sol of the material constituting the silica layer, in particular a hydrolysable compound such as a silicon alkoxide, in a particularly aqueous and / or alcoholic solvent, optionally mixed with a blowing agent,

depositing a layer of said silica sol,

a possible stage of solvent removal,

an embossing of the layer with a mask carrying patterns complementary to said low index patterns.

A method of manufacturing the organic light-emitting diode device (1000) according to the preceding method claim characterized in that the silica sol-gel layer is porous and is obtained by removal of a particularly solid pore-forming agent, the process comprising, after embossing, the formation of the low index pattern network in porous silica gel sol, by said removal of the pore-forming agent by means of a heat treatment, in particular starting at 350 ° C. followed preferably by a quenching operation.