Layer sequence for generating electroluminescence and its use

Abstract

A layer sequence for generating electroluminescence comprising at least one polycrystalline rare-earth manganate layer (1) and a first contact (2) arranged on one side of the rare-earth manganate layer (1) and a second contact (3) arranged on the opposite side of the first contact (2) or on the same side as the first contact (2), wherein a resistance greater than 100 ohms is formed in the rare-earth manganate layer (1) between the first (2) and the second contact (3) and wherein the rare-earth manganate layer (1) is capable of generating electroluminescence locally in the region of the electric field formed between the two electrically conductive contacts (2, 3) in the rare-earth manganate layer (1) due to impact ionization, wherein the layer sequence is configured such thatthat the resulting electric field when a DC voltage is applied between the first and the second contact is greater than the threshold field required for impact ionization in the rare-earth manganese layer (1) to produce electroluminescence, wherein the layer sequence is arranged on a flexible and / or transparent substrate (4).

Description

[0001] The invention relates to a layer sequence for generating electroluminescence and its use, for example in a pixel array or in textile materials.

[0002] Electroluminescence is a form of luminescence in which a solid is stimulated to emit electromagnetic radiation, e.g. in the form of light, by applying an electric field or an electric voltage.

[0003] Blue electroluminescence is observed, for example, in pn-GaN structures when majority charge carriers are injected into the space charge region and recombine there, simultaneously emitting photons. A disadvantage of pn-GaN structures is that defects in the space charge region prevent radiative recombination of electron-hole pairs, and photons can be generated in the center of the structure and reabsorbed on their way to the front or back electrode. Therefore, these structures must be highly purified, meaning they must be defect-free layers. Consequently, their fabrication is complex and expensive. Another disadvantage of these known pn-GaN structures is that the substrate must be rigid and, due to the high lattice mismatch, laterally epitaxially overgrown; otherwise, the dislocation densities would exceed 10⁻⁶. 10 cm-2 will drastically reduce the efficiency of electroluminescence.

[0004] Blue-green electroluminescence is observed, for example, in ZnS capacitive structures doped with copper, manganese, or rare-earth elements and featuring a dielectric layer to prevent breakdown. Disadvantages include the high operating voltages (130 V AC), the high AC frequency (700 Hz), and the fact that photons are only generated near one of the two contacts on the ZnS capacitive structure.

[0005] Different colored electroluminescence is also observed, for example, in metal-insulator-semiconductor structures with rare-earth doping in the insulator. The rare-earth dopants act as luminescence centers. A disadvantage is that degradation of the luminescence centers also causes degradation of the electroluminescence, making long-term stability unreliable. Furthermore, the yield of these structures is very low due to tunneling effects and is often less than 1%.

[0006] The object of the present invention is therefore to provide a layer structure that is easy to realize or manufacture and simple to construct, with which electroluminescence can be easily generated and which can be used in a long-term stable manner.

[0007] The object of the present invention is achieved by a layer sequence for generating electroluminescence, comprising at least one polycrystalline rare-earth manganate layer and a first contact arranged on one side of the rare-earth manganate layer and a second contact arranged on the opposite side of the first contact or on the same side as the first contact, wherein a resistance greater than 100 ohms is formed in the rare-earth manganate layer between the first contact and the second contact, and wherein the rare-earth manganate layer is suitable for generating electroluminescence due to impact ionization locally in the region of the electric field formed between the two electrically conductive contacts when an electric direct voltage or an electric alternating voltage is applied.

[0008] The resistance between the first and second contact is defined by a vortex density, where the vortex density is a special property of the rare-earth manganese layer and can be adjusted by applying a voltage or by undergoing a heating and / or cooling process.

[0009] Depending on the material chosen for the rare-earth manganese layer, i.e., which rare-earth manganese is selected, a different color of electroluminescence can be produced (see Fig. 2) The blue color in rare-earth manganese layers is due to Mn 3+This is due to trigonal-bipyramidal lattice sites of rare-earth manganates with YbFe2O4 structures, which cause dd transitions with an intense blue color. It was shown by Mizoguchi et al. (New Oxides Showing an Intense Blue Color Based on Mn3p in Trigonal-Bipyramidal Coordination, Hiroshi Mizoguchi, Arthur W. Sleight, and MA Subramanian, Inorg. Chem. 2011, 50, 10-12, DOI: 10.1021 / ic102133z) that the substitution of Mn 3+ on trigonal-bipyramidal lattice sites of rare-earth manganates with YbFe2O4 structures by 3d transition metals, for example as described by Smith et al. (Mn 3+ (in Trigonal Bipyramidal Coordination: A New Blue Chromophore, Andrew E. Smith, Hiroshi Mizoguchi, Kris Delaney, Nicola A. Spaldin, Arthur W. Sleight, and MA Subramanian, J. Am. Chem. Soc., 2009, 131 (47), pp 17084-17086) shown by mixing In and Mn in YIn 1-x Mn xThe color of YInO3 can be changed from white to deep blue. By adding Ti, for example, through thermally induced Ti diffusion from a Ti / Pt backside electrode into the rare-earth manganese layer during the fabrication of the rare-earth manganese layer using pulsed laser deposition and resistance heating of the SiO2 / Si substrate, the color can be changed from blue to deep blue. 1-x O3 too yellow in YMn 1-x Ti x O3 can be changed. Thus, the electroluminescence is yellow in a Y1Mn1O3 layer on a SiO2 / Si substrate with a Ti / Pt backside electrode (ID2384) and blue in a Y1Mn1O3 layer produced under identical conditions on a SiO2 / Si substrate with a Pt backside electrode (ID2386).

[0010] For the purposes of this invention, a rare-earth manganate is understood to be a material that forms vortex states when a voltage is applied or when undergoing a heating and / or cooling process. A vortex state can be understood as an intersection between charged domain walls within such a material. The resistance of the rare-earth manganate layer must be very high because electroluminescence is only generated when an electrical voltage is applied, when the current flow at the time of voltage application is negligibly small, and when an electric field greater than the threshold field of approximately 10 required for impact ionization is present. 5 - 10 6V / cm (Impact ionization in semiconductors: Effects of high electric fields and high scattering rates, J. Bude, K. Hess, GJ Iafrate, Phys. Rev. B 45 10958-10964) can form, so that impact ionization of the majority charge carriers in the electric field in the rare-earth manganese layer is possible.

[0011] The layer structure according to the invention for generating electroluminescence is particularly advantageous because it is composed of a polycrystalline rare-earth manganese layer. This means that structures exhibiting particularly high purity or a particularly low crosslinking density, as is necessary for pn-GaN structures, are not required.

[0012] A further advantage of the layer structure according to the invention lies in the fact that minority charge carriers are generated near one of the two electrically conductive contacts, this excitation can be transported by diffusion of the minority charge carriers within a sphere with the radius of the diffusion length, and only recombine with the majority charge carriers after the minority charge carrier time. This allows, for example, shadow-free, homogeneous illuminated surfaces with minimal installation depth (<1 mm) and minimal power consumption (1 W / 100 cm²). 2 ), with any external dimensions and contours. High operating voltages, as required by the aforementioned capacitance structures, are not necessary.

[0013] In an advantageous embodiment of the layer structure according to the invention for generating electroluminescence, the first contact and / or the second contact is transparent. Thus, either the first contact or the second contact can be transparent, or both contacts can be transparent to emit the generated electroluminescence into the environment.

[0014] In a further advantageous embodiment of the layer structure according to the invention for generating electroluminescence, the first contact and / or the second contact is structured. Thus, either the first contact or the second contact can be structured, or both contacts can be structured. The structured front contact can be attached to the rare-earth manganese layer on the opposite side of the structured back contact or on the same side as the structured back contact.

[0015] In a particularly advantageous embodiment of the layer structure according to the invention for generating electroluminescence, the structuring of the first and / or the second contact is designed to conduct the electroluminescence. This means that the structured electrodes enable so-called light conduction; that is, at points where no contact is formed due to the structured electrode shape, the light generated by electroluminescence can exit the layer structure, thus creating local emission points on the layer structure. Utilizing the internal reflection of light at the interface with the polycrystalline rare-earth manganese layer, the emitted light is guided within the polycrystalline layer until it reaches a point where the internal reflection is reduced, e.g., at openings of the back contact and / or the front contact, where the light is coupled out.

[0016] In one embodiment of the layer sequence according to the invention for generating electroluminescence, the rare-earth manganese layer is YMnO3. MnO3 has the advantage that this material non-volatilely forms vortex states, the density of which is reduced by reconfiguration using a single voltage pulse applied to the front and back contacts. The resistance of the YMnO3 layer is so high that a DC voltage can be applied between the front and back contacts, so that the resulting electric field is greater than the threshold field of approximately 10 required for impact ionization. 5 - 10 6 V / cm. Furthermore, rare-earth manganates have a high density of states 2-3 eV away from the valence or conduction band edge due to the Mn ions. These Mn ions serve as recombination centers for electron-hole pairs, which are generated by impact ionization.

[0017] In a further embodiment of the layer sequence according to the invention for generating electroluminescence, the YMnO3 is stoichiometrically or non-stoichiometrically doped or with 1 at-% titanium. The absorption coefficient α and the thickness d of the polycrystalline rare-earth manganese layer are determined from the complex reflection coefficient measured, for example by spectral ellipsometry, before the application of the top electrode, also known as the first contact or front contact. The absorption coefficient is greater than 10³ cm⁻¹ in the blue spectral range (2.50–2.75 eV). -1 , preferably larger than 104 cm -1 The absorption coefficient α depends on the chemical composition of the polycrystalline rare-earth manganate layer; for example, stoichiometric Y 1.00 Mn 1.00 O3 or non-stoichiometric Y 0.95 Mn 1.05 O3 or stoichiometric Y doped with 1 at-% Ti 1.00 Mn 1.00O3 or non-stoichiometric Y doped with 1 at-% Ti 0.95 Mn 1.05 O3 can be used.

[0018] In one embodiment of the layer sequence according to the invention for generating electroluminescence, the electroluminescence can be adjusted by selecting the material of the rare-earth manganate layer. Depending on the material selected for the rare-earth manganate layer, i.e., which rare-earth manganate is chosen, a different color of electroluminescence can be produced (see Fig. 2).

[0019] In an advantageous embodiment of the layer sequence according to the invention for generating electroluminescence, the layer sequence is arranged on a flexible and / or transparent substrate. The layer sequence, which comprises at least one rare-earth manganese layer as well as a first front-side contact and a second back-side contact, can be arranged on a substrate. The substrate can be flexible and / or transparent, i.e., it can, for example, be formed as a film, so that the layer sequence according to the invention can be flexibly applied to surfaces of any curvature.The advantage of the proposed mechanically flexible layer structure lies in the fact that minority charge carriers are generated near one of the two electrically conductive contacts. This excitation can be transported by diffusion of the minority charge carriers within a sphere with the radius of the diffusion length and only recombine with the majority charge carriers after the minority charge carrier time. This allows, for example, the creation of shadow-free, homogeneous illuminated surfaces with minimal installation depth (<1 mm) and minimal power consumption (1 W / 100 cm). 2 ), with any external dimensions and contours.

[0020] It is particularly advantageous to use the layer sequence according to the invention for generating electroluminescence in a pixel array for a point-like formation of electroluminescence. Point-like formation of electroluminescence is understood to mean a locally limited area where the light generated in the layer by means of electroluminescence can exit the layer into the surroundings. These pixel arrays can be used, for example, in luminescent films with shadow-free, homogeneous luminous surfaces with a small installation depth (<1 mm) and minimal power consumption (1 W / 100 cm²). 2 ) are used. For the purposes of this invention, a shallow installation depth is understood to mean a light-emitting film whose total thickness is less than 1.0 mm, preferably less than 0.5 mm, and particularly preferably less than 0.2 mm. For the purposes of this invention, a minimal power consumption is understood to mean a light-emitting film of area A whose power consumption per unit area is less than 0.10 W / cm².2 , preferably less than 0.05 W / cm² 2 and especially preferably less than 0.02 W / cm² 2It's understood. Electroluminescent (EL) films are active light sources with the properties of indirect light, equivalent to the reflection of light rays off a matte surface. Their light seems to come from nowhere and appears unrealistic and inexplicable. It appears pleasant and is not dazzling. Very short wavelengths (approx. 450 nm) are generated to create the light effect; these are easily perceptible to the human eye. Curved EL films create a three-dimensional light effect. When the electroluminescent (EL) film is attached to objects, they begin to glow. The film is a so-called Lambertian emitter, meaning the luminance of the radiation emitted from the surface is the same from every angle. With this lighting technology, there is no "radiation" from a specific light source or focal point, as with neon lights, incandescent bulbs, or LEDs.Therefore, a comparison with "radiant" light sources measured in lumens or lux is difficult. This is an absolutely homogeneous light surface that is particularly well perceived by the human eye. The light from the EL films is very narrowband, almost monochromatic, absolutely uniform, and visible from a distance.

[0021] Furthermore, it is particularly advantageous to use the layer sequence according to the invention for generating electroluminescence in a textile material, wherein the layer sequence is arranged between at least two textile substrates. A textile material can be anything that is used in the production or manufacture of a specific textile intermediate or end product and is incorporated into or consumed in this product. For example, the layer sequence according to the invention can be integrated into textile materials and used in the automotive industry, in the security sector, in advertising, in decoration, and in home textiles.

[0022] The invention will be explained in more detail below using exemplary embodiments.

[0023] The drawings show Fig. 1. Inventive layer sequence for generating electroluminescence; Fig. 2 Optical properties (absorption coefficient) and thickness d of different rare-earth manganate layers on a Pt / Ti backside electrode and on a Pt backside electrode; Fig. 3 Inventive layer sequence with structured contacts in side view, a) the contacts are located on different sides of the rare-earth manganese layer, b) the contacts are located on the same side of the rare-earth manganese layer; Fig. 4 Current-voltage characteristic of the layer sequence according to the invention when a DC voltage is applied for different rare-earth manganese layers and Pt / Ti back contact; Fig. 5 Current-voltage characteristic of the layer sequence according to the invention when a DC voltage is applied for different rare-earth manganese layers and Pt back contact; Fig. 6 Schematic representation of the location where electroluminescence is generated in the layer sequence according to the invention when a) a negative and b) a positive DC voltage is applied; Fig. 7 Formation of electroluminescence at the structured front contact a) by applying a negative voltage to the front contact, b) by applying a negative voltage to the back contact; Fig. 8. Inventive layer sequence for generating electroluminescence with two different rare-earth manganese layers; a) in side view, b) in front view / top view with emitted wavelength λ1, c) in back view with emitted wavelength λ2; Fig. 9. Inventive layer sequence for generating electroluminescence suitable for light guidance through differently optically dense materials on both sides of the rare-earth manganese layer; Fig. 10 Use of the layer sequence according to the invention for generating electroluminescence in a pixel array; Fig. 11 Use of the layer sequence according to the invention for the generation of electroluminescence in a textile material;

[0024] The Fig. Figure 1a shows a schematic side view of the layer sequence according to the invention for generating electroluminescence. The layer sequence according to the invention comprises at least one polycrystalline rare-earth manganate layer. 1 as well as an initial contact 2 , which is located on one side of the rare-earth manganese layer 1 is arranged as well as a second contact 3 , which is on the opposite side of the first contact 2 or on the same page as the first contact 2 is arranged, on. Fig. Figure 1b shows a transmission electron microscopy image of the layer sequence according to the invention. When a DC voltage is applied, a local electric field forms in the rare-earth manganese layer in the region of the electric field that develops between the two electrically conductive contacts. 1 It emits electroluminescence. Depending on the material chosen for the rare-earth manganese layer. 1 The light generated by electroluminescence has different wavelengths and therefore colors in different spectral ranges.

[0025] In Fig. 2 is the absorption coefficient of rare-earth manganate layers. 1 different compositions on a Pt backside electrode or on a Pt / Ti backside electrode 3 The absorption coefficient and the thickness of the rare-earth manganese layers are shown in the spectral range from 1.0 eV to 4.0 eV. 1were modeled from spectral ellipsometric data measured at different angles of incidence. In the blue spectral region ( 2.50 - 2.75 eV) the absorption coefficient is greater than 104 cm -1 Of the eight rare-earth manganese layers whose absorption coefficient is shown, after applying a front-side contact... 2 No electroluminescence at the three rare-earth manganese layers. 1 Y 0.95 Mn 1.05 O3, Y 1.00 Mn 0.99 Ti 0.01 O3 and Y 0.94 Mn 1.05 Ti 0.01 O3 on a Pt / Ti back contact 3 , blue electroluminescence at the four rare-earth manganese layers 1 Y1Mn1O3, Y 0.95 Mn 1.05 O3, Y 1.00 Mn 0.99 Ti 0.01 O3 and Y 0.94 Mn 1.05 Ti 0.01 O3 on a Pt backside contact 3 and yellow electroluminescence at the rare-earth manganese layer 1Y1Mn1O3 on a Pt / Ti back contact 3 observed.

[0026] Fig. Figure 3a shows the schematic representation of the layer sequence according to the invention with structured contacts. 2 , 3 , with the front side ( Fig. 3b) and the back side emits light of the same wavelength. Minority charge carriers are located near one of the two electrically conductive contacts. 2 , 3 This excitation can be generated by diffusion of minority charge carriers. 5 are transported within a sphere with the radius of the diffusion length, with the minority charge carriers 5 only after the minority charge carrier period with the majority charge carriers 6 recombine. This allows, for example, shadow-free, homogeneous illuminated surfaces with minimal installation depth (<1mm) and minimal power consumption (1W / 100cm). 2), with any external dimensions and contours.

[0027] In Fig. 4a shows the layer sequence according to the invention for generating electroluminescence in a side view. When a voltage is applied, the following results are obtained: Fig. 4b and Fig. Current-voltage curves shown in Figure 4c for different rare-earth manganese layers 1 The DC voltage must be sufficiently high so that the amplitude of the electric field reaches a value of 1000 kVcm. -1 exceeds this condition for the three rare-earth manganese layers 1 Y 0.95 Mn 1.05 O3, Y 1.00 Mn 0.99 Ti 0.01 O3 and Y 0.94 Mn 1.05 Ti 0.01 O3 on a Pt / Ti back contact 3 This condition is not met, therefore no electroluminescence is observed on these layers. This condition applies to the rare-earth manganese layer. 1 Y1Mn1O3 on a Pt / Ti back contact 3fulfilled for positive DC voltages. At the rare-earth manganese layer 1 Y1Mn1O3 on a Pt / Ti back contact 3 Yellow electroluminescence is observed.

[0028] Fig. Figure 5a shows the layer sequence according to the invention for generating electroluminescence, wherein the current-voltage curves in the Fig. 5b and Fig. 5c on different rare-earth manganese layers 1 with a Ti-doped back contact 3 The DC voltage must be sufficiently high so that the amplitude of the electric field reaches a value of 1000 kVcm. -1 exceeds this condition. This condition applies to the four rare-earth manganese layers Y1Mn1O3, Y 0.95 Mn 1.05 O3, Y 1.00 Mn 0.99 Ti 0.01 O3 and Y 0.94 Mn 1.05 Ti 0.01 O3 on a Pt back contact for negative DC voltages is fulfilled and for the three rare-earth manganese layers Y 0.95Mn 1.05 O3, Y 1.00 Mn 0.99 Ti 0.01 O3 and Y 0.94 Mn 1.05 Ti 0.01 O3 is present on a Pt back contact for positive DC voltages. In these cases, blue electroluminescence is observed.

[0029] Fig. Figure 6 shows a schematic representation of the location where electroluminescence is generated in the layer sequence according to the invention when a DC voltage is applied. The majority charge carriers 6 are holes and minority charge carriers 5 are electrons. The minority charge carriers 5 are generated near the positive electrically conductive contact, with the minority charge carriers 5 within a sphere with the radius of the diffusion length, and only after the minority charge carrier time with the majority charge carriers 6recombine. This allows, for example, shadow-free, homogeneous illuminated surfaces with minimal installation depth (<1mm) and minimal power consumption (1W / 100cm). 2 ), with any external dimensions and contours.

[0030] Fig. Figure 7a shows the formation of electroluminescence when a negative voltage is applied to the front contact. 2 and Fig. 7b when a negative voltage is applied to the back contact 3 The one on the front electrode 2 observed blue electroluminescence ( Fig. 7) is stronger when a negative voltage is applied to the front electrode 2 ( Fig. 7a) compared to applying a positive voltage to the front electrode 2 ( Fig. 7b).

[0031] Fig. Figure 8a shows the schematic representation of the layer sequence according to the invention for generating electroluminescence with two different polycrystalline rare-earth manganese layers. 1 , 11 Due to the choice of material for the polycrystalline rare-earth manganese layers, the electroluminescence produced on the front and back sides exhibits different wavelengths. λ1 ( Fig. 8b) and λ 2 ( Fig. 8b) on.

[0032] The in Fig. Figure 9, schematically depicted, is a layer sequence according to the invention for generating electroluminescence and is suitable for guiding and extracting the electroluminescent light. This is achieved through the use of materials with different optical densities. 12 , 13 on both sides of the rare earth manganese layer 1Various structures can be realized for light guiding and light extraction. Light guiding utilizes the internal reflection of light at the interface with the polycrystalline rare-earth manganese layer. 1 , the emitted light in the polycrystalline layer 1 guided until it reaches a point where internal reflection is reduced, e.g. at openings of the back contact. 3 and / or the front contact 2 , that's where the light is extracted.

[0033] Fig. Figure 10 shows a schematic representation of the layer sequence according to the invention, which is used in a pixel array. In this figure, Fig. 10a The front contact is structured and designed as a wordline, and the back contact is designed as a bitline. In Fig. In 10b, the front contact is designed as a wordline, and the back contact is structured and designed as a bitline. Fig. 10c and Fig. 10d each show the ones in the Fig. 10a and Fig. Structures described in Figure 10b in front and back views.

[0034] Fig. Figure 11 shows a schematic representation of the layer sequence according to the invention in use in a textile material. Reference symbol list 1 polycrystalline rare-earth manganate layer 2. First contact, front contact 3. Second contact, back contact 4 Substrat 5 minority charge carriers of the polycrystalline rare-earth manganate layer 6 Majority charge carriers of the polycrystalline rare-earth manganate layer 7 Protective film 8 Energy source, e.g. battery 11 second / additional polycrystalline rare-earth manganate layer 12. Optically thinner material than polycrystalline rare-earth manganese layer 13. Optically denser material than polycrystalline rare-earth manganese layer 6A Side view during and 0-3 s after applying -V to the front contact; 6B Side view during and 0-3 s after applying +V to the front contact; 7A Top view 0-3 s after applying -V to the front contact; 7B Top view 0-3 s after applying +V to the front contact; 8X Electroluminescence at wavelength λ1 at the front contact and at wavelength λ2 on back contact; 9X Different structures for light guiding and light extraction; Light guiding by utilizing the internal reflection of light at the interface of the polycrystalline layer; Light extraction at the point where internal reflection is reduced, e.g. at openings of the back contact and the front contact; 10A Three electrically conductive, front-side contacts 4 (structured as a wordline); Electrically conductive back contact 3 (structured as a bitline); 10B Three electrically conductive, rear-side contacts 3 (structured as a bitline); Electrically conductive front contact 4 (structured as a wordline); 10C Pixel ij emits light when -V ij Pixels are created 13 , 31 and 32 emit light; 10D pixel ij emits light when +V ij Pixels are created 12 and 21 emit light; 11X Integration into textiles: Single cell and pixel array preparation on textile material as a carrier or incorporation into textiles

Claims

[1] Layer sequence for generating electroluminescence comprising at least one polycrystalline rare-earth manganate layer (1) and a first contact (2) arranged on one side of the rare-earth manganate layer (1) and a second contact (3) arranged on the opposite side of the first contact (2) or on the same side as the first contact (2), wherein a resistance greater than 100 ohms is formed in the rare-earth manganate layer (1) between the first (2) and the second contact (3) and wherein the rare-earth manganate layer (1) is suitable to produce electroluminescence due to impact ionization locally in the region of the electric field formed between the two electrically conductive contacts (2, 3) in the rare-earth manganate layer (1) when an electric direct voltage or an electric alternating voltage is applied. [2] Layer sequence for generating electroluminescence according to claim 1, characterized by , that the first contact (2) and / or the second contact (3) is transparently formed. [3] Layer sequence for generating electroluminescence according to one of claims 1 or 2, characterized by that the first contact (2) and / or the second contact (3) is structured. [4] Layer sequence for generating electroluminescence according to one of the preceding claims, characterized by , that the structuring of the first and / or second contact (2, 3) is designed to conduct electroluminescence, for example in a pixel array. [5] Layer sequence for generating electroluminescence according to claim 1, characterized by that the rare earth manganese layer is YMnO3. [6] Layer sequence for generating electroluminescence according to claim 5, characterized bythat the YMnO3 is stoichiometric or non-stoichiometric or is doped with 1 at-% titanium. [7] Layer sequence for generating electroluminescence according to one of the preceding claims, characterized by , that the layer sequence is arranged on a flexible and / or transparent substrate (4). [8] Use of the layer sequence for generating electroluminescence according to one of claims 1 to 7 in a pixel array for a point-like formation of the electroluminescence. [9] Use of the layer sequence for generating electroluminescence according to any one of claims 1 to 7 in a textile material, wherein the layer sequence is arranged between at least two textile substrates. [10] Use of the layer sequence for generating electroluminescence according to any one of claims 1 to 7 in the area of ​​the first contact or in the area of ​​the second contact.

Images