Light-emitting component and method for manufacturing a light-emitting component

Abstract

Light-emitting component, comprising: • an organically functional layered structure (108) designed to emit a first light (116), and • a light-scattering layer (104) with a multitude of quantum dots (114), • wherein the light-scattering layer (104) is arranged in the beam path of at least a part of the emittable light of the organically functional layer structure (108); wherein the quantum dots (114) are configured to absorb a second light in a first wavelength range and to emit at least a part of the absorbed light in a second wavelength range, wherein the color valence of the second wavelength range is approximately equal to the color valence of the first wavelength range, wherein the first light (116) and the second light have an essentially the same wavelength range, wherein the quantum dots (114) have a mean diameter of less than 100 nm, wherein the quantum dots (114) are essentially configured to be non-refracting and / or non-reflective for visible light, wherein the light-scattering layer (104) further comprises a matrix wherein the quantum dots (114) are embedded in the matrix, and wherein the matrix comprises an electrically conductive material.

Description

[0001] The invention relates to a light-emitting component and a method for manufacturing a light-emitting component.

[0002] The following publications disclose light-emitting components: CN 104 576 703 A, KR 10 2015 089 975 A, WO 2009 / 014 707 A2, DE 10 2013 113 486 A1.

[0003] A conventional light-emitting device, such as an OLED, can have an anode and a cathode with an organic functional layer system in between. This organic functional layer system can include one or more emitter layers in which electromagnetic radiation is generated, one or more charge-generating layer (CGL) structures consisting of two or more CGLs for charge-generating technology, one or more hole-blocking layers (HTLs) and one or more electron-blocking layers (ETLs) to direct current flow.

[0004] So far, there are two approaches to increasing light extraction from a light-emitting component: external extraction and internal extraction.

[0005] External coupling refers to devices in which light from the substrate is coupled out into emitted light. Such a device could be, for example, a film with scattering particles or a surface structure, such as microlenses.

[0006] The film can, for example, be applied to the outside of the substrate.

[0007] Internal coupling can be understood as devices in which light is coupled out that is guided in the electrically active area of ​​the light-emitting component, for example the organic functional layer structure and / or the electrodes, i.e. the transparent conductive oxide layers (TCO).

[0008] In a conventional device for internal light extraction, a scattering layer can be applied over or onto an electrode, for example, the indium tin oxide anode. The scattering layer can have a polymer matrix in which scattering particles are dispersed.

[0009] Fig. Figure 5 shows a diagram 500 illustrating the direct transmission 502 of light through a scattering layer containing scattering particles as a function of the wavelength 504 of the light for scattering layers with different particle diameters (506: 25 nm; 508: 50 nm; 510: 100 nm; 512: 200 nm; 514: 400 nm; 516: 800 nm; 518: 1600 nm). The diagram 500 shows the scattering behavior for particles of different sizes and demonstrates that a clear isolation of a narrowband wavelength range for scattering with scattering particles is not possible. This means that, so far, only scattering films that act over a broad wavelength spectrum are known. This is because scattering is wavelength-dependent, and while it is possible to generate a certain degree of dispersion, it is not possible to exclude a specific wavelength range.

[0010] By using scattering particles for decoupling, the appearance of the light-emitting component can be significantly influenced. For example, the applied layers or films can create a milky-looking and / or diffusely reflective surface on the light-emitting component.

[0011] Previously, attempts were made to optimize conventional diffusing films / layers of light-emitting devices for monochrome or narrowband applications. However, the broadband diffusing films known to date can have the disadvantage that the light-emitting device no longer exhibits reflective properties. Furthermore, in the off-state, the conventional light-emitting device can scatter ambient light and therefore generally appear whitish or milky. This is particularly undesirable for monochrome light-emitting devices, such as monochrome organic light-emitting diodes (OLEDs), which emit, for example, red or yellow light.

[0012] Furthermore, quantum dots are known from Demir et al. “Quantum dot integrated LEDs using photonic and excitonic color conversion” Nano Today (2011) 6, 632-647. However, to date, quantum dots have only been used to increase the wavelength (down conversion) of light.

[0013] The object of the invention is to provide a light-emitting component and a method for its manufacture, wherein the light-emitting component has a light-scattering layer that does not or does not significantly affect the appearance of the light-emitting component in the off-state, for example, a reflective off-state of the light-emitting component is maintained.

[0014] A light-emitting device is provided, comprising an organically functional layer structure configured to emit a first light and a light-scattering layer with a plurality of quantum dots. The light-scattering layer is positioned in the beam path of at least a portion of the emittable light from the organically functional layer structure. The quantum dots are configured to absorb a second light in a first wavelength range and to emit at least a portion of the absorbed light in a second wavelength range, the color valence of the second wavelength range being approximately equal to the color valence of the first wavelength range.

[0015] A wavelength range can be a continuous range of wavelengths. For example, emittable light exhibits significant intensity in the wavelength range from approximately 520 nm to approximately 580 nm. The global intensity maximum is located within this wavelength range. However, the wavelength range can also have a different starting and / or ending wavelength. Furthermore, the wavelength range can be smaller or narrower, or larger or wider.

[0016] A wavelength or wavelength range of electromagnetic radiation can be understood to have little or no technical relevance if the intensity of the emittable light is less than approximately 5% of the intensity of the global or local intensity maximum of the wavelength range or wavelength spectrum.

[0017] Alternatively, a wavelength range can also have several wavelength ranges. To illustrate, the emittable light exhibits significant intensity in the wavelength range from approximately 520 nm to approximately 580 nm and also in the range from approximately 620 nm to approximately 750 nm. For example, the global intensity maximum and / or one or more local maxima are located within this wavelength range.

[0018] Furthermore, a wavelength range can also be understood as a color locus range of a color standard chart, for example as a one-dimensional range of values, for example with constant Cx or Cy; or as a two-dimensional range of values ​​of the coordinates Cx and Cy of the color standard chart.

[0019] Within the context of this description, color valence can be understood as a physiological, colored effect of electromagnetic radiation. Color valences can be single colors or mixed colors. Single colors can, for example, exhibit green, red, or yellow light, and / or mixed colors can, for example, be a mixture of green, red, and / or yellow light, and / or exhibit white light. A color valence can be determined as a color locus (Cx, Cy) in a CIE colorimetric chart.

[0020] This causes the quantum dots to scatter the emitted light without changing the color valence of the total emitted light, that is, the first light and / or the non-absorbed part of the second light.

[0021] In quantum dots, the absorption and emission spectra overlap. This makes it possible to absorb light and re-emit light of the same wavelength. The re-emitted light is emitted at a different angle than the absorbed light and is thus, figuratively speaking, scattered. Therefore, quantum dots are narrowband, wavelength-selective scattering centers. In the light-emitting state of the device, quantum dots do not, in essence, cause any visible wavelength conversion, but rather serve to scatter light.

[0022] Quantum dots can exhibit high conversion efficiency, for example over 95%, when converted using the same color, such as in solution. This enables highly efficient and narrowband scattering.

[0023] In various embodiments, the light-emitting component exhibits a reflective appearance or properties, except in the narrowband wavelength range of absorption and emission by the quantum dots, where a portion of the incident light is absorbed and (re)emitted. Alternatively or additionally, when switched off, the light-emitting component scatters ambient light and therefore appears as it is configured by the quantum dots, for example, reddish.

[0024] The first and second light sources have essentially the same wavelength range. In other words, the quantum dots of the multitude of quantum dots are configured to absorb at least a portion of the light emitted by the organic functional layer structure and re-emit it at a second wavelength range. The light emitted by the quantum dots is emitted at a reflection angle that differs from the incidence angle of the absorbed light. This allows the quantum dots to scatter the emittable light of the organic functional layer structure as well as external light of the same wavelength range without causing any significant distortion in the color valence.In other words, the solid angle of the light emitted by the light-emitting component can be increased by means of the quantum dots without significantly changing the relative spectral bandwidth.

[0025] In a further refinement, the second wavelength range has a maximum full width at half maximum (FWHM) of 75 nm. This ensures that the color valence of the light emitted by the light-emitting component, i.e., the first light and the light emitted by the quantum dots, remains essentially unchanged.

[0026] The quantum dots are essentially non-refracting and / or non-reflective for visible light. The quantum dots of the multitude of quantum dots essentially have an average diameter smaller than 100 nm, for example, in a range of approximately 5 nm to approximately 90 nm, for example, in a range of approximately 10 nm to approximately 75 nm, for example, in a range of approximately 25 nm to approximately 60 nm. By absorbing the second light and emitting a portion of the absorbed light with approximately the same color valence, the second light can be scattered by the quantum dots without being refracted or reflected, since the dimensions of the quantum dots are too small for scattering or refraction of light to occur. Furthermore, other light, such as the first light or visible light external to the device, is also not scattered or refracted by the quantum dots.Light-reflecting particles can alter the appearance of a light-emitting component, for example, making it appear milky or cloudy. Quantum dots can prevent such changes in appearance while still allowing second-order light scattering.

[0027] The light-scattering layer further comprises a matrix in which the quantum dots are embedded. The matrix consists of an electrically conductive material, such as a transparent conductive oxide (TCO), for example, tin oxide, zinc oxide, indium tin oxide, aluminum zinc oxide, or similar. Alternatively or additionally, the matrix can consist of, or be composed of, an electrically non-conductive material, such as a polymer or resin. This facilitates the formation of the light-scattering layer and ensures that the quantum dots exhibit cohesion within the layer, thereby increasing the durability of the light-emitting device. Furthermore, the matrix can act as a barrier against substances that are harmful to the quantum dots, such as water and / or oxygen, which could cause degradation of the quantum dots.

[0028] In a further refinement, the matrix is ​​essentially colorless and transparent. This allows the second light to reach the quantum dots within the light-scattering layer virtually unchanged or unaffected. This increases the efficiency of the light-scattering layer without altering the appearance of the light-emitting component.

[0029] In a further refinement, the light-emitting component also features a mirror structure. This mirror structure is positioned in the path of the first and / or second light rays. The mirror structure exhibits a reflectivity of at least 80% with respect to the first and / or second light rays. This causes the light-emitting component to have a mirror-like appearance in the off-state, as light incident on the component is reflected specularly by the mirror structure. The quantum dots do not scatter this light in the off-state; that is, they do not alter the mirror-like appearance of the light-emitting component.In the energized state, that is, in the switched-on, light-emitting state, also referred to as the ON state, the quantum dots can scatter the second light, thus increasing the solid angle of the emittable light. In this state, the mirror structure also increases the proportion of light emitted by the light-emitting component in the direction opposite to the direction of incidence of the mirror structure.

[0030] In a further refinement, the light-scattering layer has a thickness that is less than the mean free path of the first light in the light-scattering layer with respect to the quantum dots. This means that light incident perpendicularly onto the light-scattering layer is not scattered, or only to a very small extent, by the quantum dots. As a result, the light-scattering layer does not appear milky or cloudy when viewed perpendicularly or substantially perpendicularly, that is, at an angle of incidence of approximately 0° to the normal.

[0031] In a further development, the light-emitting component also features an encapsulation structure. This encapsulation structure is designed to encapsulate at least the organic functional layer structure and the light-scattering layer. The encapsulation structure is essentially hermetically sealed with respect to water and / or oxygen. The encapsulation structure may include, for example, a barrier thin film, a thin-film encapsulation, a getter, a cover, and / or a laminated cover. For example, the light-scattering layer and the organic functional layer structure are monolithically encapsulated by the encapsulation structure. The encapsulation structure may, for example, have different encapsulation elements in different areas of the light-emitting component.For example, the encapsulation structure completely or substantially completely surrounds the organic functional layer structure and the layer. This protects the organic functional layer structure and the light-scattering layer from degradation and thus increases the durability and robustness of the light-emitting device.

[0032] In a further development, the light-emitting component also includes a substrate. The light-scattering layer is formed on or above the substrate, and the organically functional layer structure is arranged on or above the light-scattering layer.

[0033] In a further training, the substrate is essentially transparent to visible light and the first light can be emitted through the substrate.

[0034] In a further development, the light-emitting component also features an essentially transparent electrode for energizing the organically functional layer structure. The transparent electrode is positioned between the light-scattering layer and the organically functional layer structure.

[0035] In a further development, the organic functional layer structure features a light-scattering layer. For example, the quantum dots are integrated into a light-scattering layer of the organic functional layer structure. This enables a simple construction of the light-emitting device, for example, without an additional matrix or support material, such as a solvent, for the quantum dots.

[0036] In a further aspect, a method for fabricating a light-emitting device is provided. The method involves forming an organically functional layer structure configured to emit a first light and forming a light-scattering layer with a multitude of quantum dots. The light-scattering layer is positioned in the beam path of at least a portion of the emittable light from the organically functional layer structure. The quantum dots are configured to absorb a second light in a first wavelength range and to emit at least a portion of the absorbed light in a second wavelength range, where the color valence of the second wavelength range corresponds approximately to the color valence of the first wavelength range.

[0037] In various advanced training courses, the process for manufacturing the light-emitting component exhibits the same characteristics as the light-emitting component itself, and vice versa.

[0038] Exemplary embodiments of the invention are shown in the figures and are explained in more detail below.

[0039] They show: Fig. 1 a schematic sectional view of an embodiment of a light-emitting component; Fig. 2 a schematic sectional view of an embodiment of a light-emitting component, Fig. 3A, Fig. 3B Diagrams of the absorption and emission of a light-scattering layer according to various embodiments; Fig. 4. A flowchart of a method for manufacturing a light-emitting component according to various embodiments; and Fig. 5 a diagram of the transmission of a conventional scattering layer.

[0040] The following detailed description refers to the accompanying drawings, which form part of this description and in which specific embodiments are shown for illustration purposes, illustrating how the invention can be implemented. Since components of embodiments can be positioned in a number of different orientations, the directional terminology serves only for illustration and is in no way restrictive. It is understood that other embodiments may be used and structural or logical modifications may be made without deviating from the scope of protection of the present invention. It is understood that the features of the various embodiments described herein may be combined with one another, unless specifically stated otherwise. In the figures, identical or similar elements are provided with identical reference numerals where appropriate.

[0041] A light-emitting assembly can contain one, two, or more light-emitting components. Optionally, a light-emitting assembly can also contain one, two, or more electronic components. An electronic component can, for example, be an active and / or a passive component. An active electronic component can, for example, be a computing, control, and / or regulating unit and / or a transistor. A passive electronic component can, for example, be a capacitor, a resistor, a diode, or an inductor.

[0042] A light-emitting device is a device that emits electromagnetic radiation. In various embodiments, an electromagnetic radiation-emitting device can be a semiconductor device and / or be designed as an electromagnetic radiation-emitting diode, an organic electromagnetic radiation-emitting diode, an electromagnetic radiation-emitting transistor, or an organic electromagnetic radiation-emitting transistor. The radiation can be, for example, visible light, ultraviolet light, and / or infrared light.In this context, the electromagnetic radiation-emitting component can be designed, for example, as a light-emitting diode (LED), an organic light-emitting diode (OLED), a light-emitting transistor, or an organic light-emitting transistor. The light-emitting component can be part of an integrated circuit in various embodiments. Furthermore, multiple light-emitting components can be provided, for example, housed in a common package.

[0043] Depending on various configurations, the light-emitting component (e.g., organic light-emitting component such as OLED) can be designed as a "bottom emitter".

[0044] The term "bottom emitter" or "bottom-emitting light-emitting device," as used herein, refers to a design that is transparent towards the substrate side of the light-emitting device. For example, at least the substrate and any layers formed between the substrate and the at least one functional layer (e.g., an electrode (base electrode) formed between the substrate and the functional layer(s)) can be transparent. A light-emitting device designed as a bottom emitter can therefore emit radiation generated in the functional layers (e.g., organic functional layers in an organic light-emitting device such as an OLED) onto the substrate side of the light-emitting device.

[0045] Alternatively or additionally, the light-emitting component can be designed as a "top emitter" according to various embodiments.

[0046] The term "top emitter" or "top-emitting light-emitting device," as used herein, refers, for example, to a design that is transparent on the side facing away from the substrate (in other words, the top side) of the light-emitting device. In particular, the layers formed on or above the at least one functional layer of the light-emitting device (e.g., the electrode (top electrode) formed between the functional layer(s) and the barrier thin film, the barrier thin film, the intermediate layer, the top layer) can be transparent. A light-emitting device designed as a top emitter can therefore, for example, emit radiation generated in the functional layers (e.g., organic functional layers in an organic light-emitting device such as an OLED) onto the top side of the light-emitting device.

[0047] A light-emitting component designed as a top emitter, according to various embodiments, can advantageously exhibit high light output and very low angular dependence of the radiation density. A light-emitting component according to various embodiments can advantageously be used for lighting applications, such as room luminaires.

[0048] A combination of bottom-emitter and top-emitter is also provided in various embodiments. In such a design, the light-emitting device is generally able to emit the light generated in the functional layers (e.g., the organic functional layers in an organic light-emitting device such as an OLED) in both directions – that is, both towards the substrate side and towards the top side (transparent or translucent OLED).

[0049] Fig. Figure 1 shows a schematic sectional view of an embodiment of a light-emitting component according to various embodiments.

[0050] The light-emitting component 100 has a substrate 102.

[0051] A light-scattering layer 104, which has a large number of quantum dots 114, is arranged on or above the substrate 102.

[0052] Furthermore, an active region 130 is formed on or above the substrate 102. The active region 130 has a first electrode layer 106 and a second electrode layer 110, as well as an organically functional layer structure 108 between the first and second electrode layers 106, 110. The organically functional layer structure is configured to emit a first light (in Fig. 1 illustrated by means of the arrow 116).

[0053] In various embodiments, the light-emitting component 100 also has an encapsulation structure 112. The encapsulation structure 112 encapsulates the light-scattering layer 104 and at least the organically functional layer structure 108 essentially completely from harmful influences, such as water, oxygen, and / or UV radiation. For example, the encapsulation structure 112 completely surrounds the light-scattering layer 104 and at least the organically functional layer structure 108, for example the active area 130, for example up to the substrate 102 and / or except for one or more contact areas.

[0054] Light external to the component can fall onto the light-emitting component 100 (in Fig. 1 illustrated by arrow 118). At least a portion of the component-external light 118 is reflected by the light-emitting component. The reflected portion of the component-external light can be a component of the light emitted or emittable by the light-emitting component (not illustrated).

[0055] In other words, the organically functional layer structure 108 is configured to emit a first light 116. The light-scattering layer 104 has a multitude of quantum dots 114. The light-scattering layer 104 is arranged in the beam path of at least a portion of the emittable light 116 of the organically functional layer structure 108. The quantum dots 114 are configured to absorb a second light in a first wavelength range and to emit at least a portion of the absorbed light in a second wavelength range. The color valence of the second wavelength range corresponds approximately to the color valence of the first wavelength range.

[0056] This causes the quantum dots to scatter the emitted light without altering the color valence of the total emitted or emittable light, that is, the first light and / or the unabsorbed portion of the second light. The quantum dots of the multitude of quantum dots are configured such that they can absorb at least a portion of the light emittable by the organic functional layer structure and re-emit it at a second wavelength range. The light emitted by the quantum dots is essentially emitted at an angle of reflection that differs from the angle of incidence of the absorbed light. This allows the quantum dots to scatter the emittable light of the organic functional layer structure as well as external light of the same wavelength range without causing any significant distortion in the color valence.In other words, the solid angle of the light emitted by the light-emitting device can be increased by means of quantum dots without significantly altering the relative spectral bandwidth. Through absorption of the second light and emission of a portion of the absorbed light with approximately the same color valence, the second light can be scattered by the quantum dots without being refracted or reflected, since the dimensions of the quantum dots are too small for scattering or refraction to occur. Furthermore, other light, such as the first light or visible light external to the device, is also not scattered or refracted by the quantum dots. Light-refracting or light-reflecting particles can alter the appearance of the light-emitting device, for example, making it appear milky or cloudy.Using quantum dots, such a change in appearance can be prevented, and yet second light can still be scattered.

[0057] External white light 118 incident on the light-emitting component is emitted in a different wavelength range depending on the concentration of quantum dots 114 (see Fig. 3A, B). This slightly reduces the intensity of the specularly reflected light, but does not prevent it. In the off state, the light-emitting component therefore has a reflective or specular appearance with a color tint in the range of the color valence of the second wavelength range.

[0058] The first light 116 and the second light can have essentially the same wavelength range.

[0059] The second wavelength range can have a maximum full width at half maximum (FWHM) of 75 nm, for example in a range from approximately 10 nm to approximately 75 nm, for example in a range from approximately 15 nm to approximately 65 nm, for example in a range from approximately 25 nm to approximately 55 nm.

[0060] The quantum dots 114 are essentially non-refracting and / or non-reflective for visible light.

[0061] The light-scattering layer 104 further comprises a matrix in which the quantum dots 114 are embedded. The matrix is ​​essentially colorless and transparent. The matrix, or the matrix material, has a high refractive index, for example, greater than 1.7, for instance, in the range of 1.7 to 2.2. The refractive index of the matrix, or the matrix material, can be approximately equal to the layer-thickness-averaged refractive index of the active region or the organically functional layer structure.

[0062] A mirror structure is arranged in the beam path of the first light 116 and / or the second light and has a reflectivity of at least 80% with respect to the first light 116 and / or the second light. In various embodiments, a mirror structure can reflect electromagnetic radiation. A mirror structure can be configured in various embodiments as an optical grating, a metallic mirror, a photonic crystal, or a totally reflecting interface. A mirror structure can be configured to be fully or partially reflective with respect to electromagnetic radiation of a specific wavelength range, for example, as a partially transparent mirror structure, such as a dichroic mirror. The partially transparent mirror structure can, for example, be a beam splitter and / or a one-way mirror.The partially transparent mirror structure can, for example, reflect a portion of the incident electromagnetic radiation, while the remaining portion passes through. The partially transparent mirror structure can, for example, have a dielectric layer system on one side and / or, optionally, an anti-reflective coating on the other side, for instance, to prevent double images. Alternatively or additionally to the dielectric layer system, a very thin metal coating can also be used.

[0063] The light-scattering layer 104 can have a thickness that is smaller than a mean free path of the first light 116 in the light-scattering layer 104 with respect to the quantum dots 114.

[0064] The encapsulation structure 112 is designed to encapsulate at least the organic functional layer structure 108 and the light-scattering layer 104, wherein the encapsulation structure 112 is essentially hermetically sealed with respect to water and / or oxygen.

[0065] The light-scattering layer 104 is arranged on or above the substrate 102. The organically functional layer structure 108 is arranged on or above the light-scattering layer 104. The substrate 102 is essentially transparent to visible light, and the first light 116 is emittable through the substrate 102.

[0066] The first electrode layer 106 is an essentially transparent electrode 106 for energizing the organically functional layer structure 108. The transparent electrode 106 is arranged between the light-scattering layer 104 and the organically functional layer structure 108.

[0067] The second wavelength range can be separated from the first wavelength range by one Stokes shift. Alternatively, the second wavelength range can be separated from the first wavelength range by one anti-Stokes shift. The second and first wavelength ranges can share a common overlap region.

[0068] In various training courses, the first light and the second light exhibit essentially different wavelength ranges.

[0069] In various embodiments, the substrate 102 has the light-scattering layer 104. For example, the substrate is structured and has the light-scattering layer 104 in the region of the (optically) active area 130 and is free of light-scattering layer 104 outside the (optically) active area 130.

[0070] In various embodiments, the light-scattering layer has one or more cavities that are at least partially filled with a solution of solvent for the quantum dots and the quantum dots themselves. This enables the quantum dots to exhibit a high light conversion efficiency.

[0071] In various embodiments, the light-scattering layer is structured and exhibits areas with varying concentrations of quantum dots and / or different types of quantum dots. This allows the light-emitting component to be used easily for information display, for example as a sign or display (signage applications).

[0072] Fig. Figure 2 shows a schematic cross-sectional view of a light-emitting component 100, which, for example, largely corresponds to the one in Fig. can correspond to the embodiment shown in 1. Fig. 2 the light-scattering layer 104 is not illustrated, since in various embodiments the active area 130, for example the organic functional layer structure 108 or an electrode 106, 110; has the quantum dots 114 and is thus the light-scattering layer 104.

[0073] The light-emitting component 100 comprises the substrate 102 described above. The substrate 102 is at least partially translucent or transparent. The substrate 102 can, for example, comprise or be formed from plastic, metal, glass, quartz, and / or a semiconductor material; for example, the matrix can comprise or be formed from a metal. Furthermore, the substrate 102 can comprise or be formed from a plastic film or a laminate containing one or more plastic films. The substrate 102 can be mechanically rigid or mechanically flexible.

[0074] The active region 130 is formed on the substrate 102. The active region has the first electrode layer 106, which includes a first contact section 16, a second contact section 18, and a first electrode 20. The first electrode layer 106 can also be part of the substrate 102. A first barrier layer (not shown), for example, a first barrier thin film, can be formed between the substrate 102 and the first electrode layer 106.

[0075] The first electrode 20 is electrically isolated from the first contact section 16 by means of an electrical insulating barrier 21. The second contact section 18 is electrically coupled to the first electrode 20. The first electrode 20 can be configured as an anode or as a cathode. The first electrode 20 can be translucent or transparent. The first electrode 20 comprises an electrically conductive material, for example, a metal and / or a transparent conductive oxide (TCO), or a stack of multiple layers comprising metals or TCOs. The first electrode 20 can, for example, have a stack of layers combining a layer of a metal on a layer of a TCO, or vice versa. An example is a silver layer deposited on an indium tin oxide (ITO) layer (Ag on ITO) or ITO-Ag-ITO multilayers.The first electrode 20 can alternatively or additionally comprise: networks of metallic nanowires and particles, for example made of Ag, networks of carbon nanotubes, graphene particles and layers and / or networks of semiconducting nanowires.

[0076] Above the first electrode 20, the organic functional layer structure 108 is formed, which is configured to emit light. The organic functional layer structure 108 can, for example, have one, two, or more sublayers. For example, the organic functional layer structure 108 can have a hole injection layer, a hole transport layer, an emitter layer, an electron transport layer, and / or an electron injection layer. The hole injection layer serves to reduce the band gap between the first electrode 20 and the hole transport layer. In the hole transport layer, the hole conductivity is greater than the electron conductivity. The hole transport layer serves to transport the holes. In the electron transport layer, the electron conductivity is greater than the hole conductivity. The electron transport layer serves to transport the electrons.The electron injection layer serves to reduce the band gap between the second electrode and the electron transport layer. Furthermore, the organic functional layer structure 108 can comprise one, two, or more functional layer structure units, each containing the aforementioned sublayers and / or further intermediate layers.

[0077] Above the organic functional layer structure 108, the second electrode layer 110 is formed, which can also be referred to as the second electrode 110. The second electrode 110 is electrically coupled to the first contact section 16. The second electrode 110 can be configured according to one of the embodiments of the first electrode 20, whereby the first electrode 20 and the second electrode 110 can be identical or different. The first electrode 20 serves, for example, as the anode or cathode of the active region. Correspondingly, the second electrode 110 serves as the cathode or anode of the active region.

[0078] A getter structure (not shown), which is part of the encapsulation structure 112, can be arranged on or above the active region 130. The getter layer can be translucent, transparent, or opaque. The getter layer can comprise or be formed from a material that absorbs and binds substances harmful to the active region.

[0079] An encapsulation layer 24 of the active region is formed over the second electrode 110 and partially over the first contact section 16 and partially over the second contact section 18, encapsulating the active region. The encapsulation layer 24 is part of the encapsulation structure 118 and can be configured as a second barrier layer, for example, as a second barrier thin film. The encapsulation layer 24 can also be referred to as thin-film encapsulation. The encapsulation layer 24 forms a barrier against chemical impurities and atmospheric substances, in particular against water (moisture) and oxygen. The encapsulation layer 24 can be configured as a single layer, a stack of layers, or a layered structure.The encapsulation layer 24 can comprise or be formed from: aluminum oxide, zinc oxide, zirconium oxide, titanium oxide, hafnium oxide, tantalum oxide, lanthanum oxide, silicon oxide, silicon nitride, silicon oxynitride, indium tin oxide, indium zinc oxide, aluminum-doped zinc oxide, poly(p-phenylene terephthalamide), nylon 66, as well as mixtures and alloys thereof. Optionally, the first barrier layer on the substrate 102 can be configured corresponding to an embodiment of the encapsulation layer 24.

[0080] In the encapsulation layer 24, a first recess is formed above the first contact section 16, and a second recess is formed above the second contact section 18. A first contact area 32 is exposed in the first recess, and a second contact area 34 is exposed in the second recess. The first contact area 32 serves to electrically contact the first contact section 16, and the second contact area 34 serves to electrically contact the second contact section 18.

[0081] Above the encapsulation layer 24, an adhesive layer 36 is formed, which is part of the encapsulation structure 118. The adhesive layer 36 comprises, for example, an adhesive, such as a laminating adhesive, a varnish, and / or a resin. The adhesive layer 36 may, for example, contain particles that scatter electromagnetic radiation, such as light-scattering particles.

[0082] A cover body 38, which is also part of the encapsulation structure 118, is formed above the adhesive layer 36. The adhesive layer 36 serves to attach the cover body 38 to the encapsulation layer 24. The cover body 38 comprises, for example, plastic, glass, and / or metal. For example, the cover body 38 can be made primarily of glass and have a thin metal layer, such as a metal foil, and / or a graphite layer, such as a graphite laminate, on the glass body. The cover body 38 serves to protect the conventional light-emitting component 1, for example, from external mechanical forces. Furthermore, the cover body 38 can serve to distribute and / or dissipate heat generated in the conventional light-emitting component 1.For example, the glass of the cover body 38 can serve as protection against external influences and the metal layer of the cover body 38 can serve to distribute and / or dissipate the heat generated during the operation of the conventional light-emitting component 1.

[0083] Fig. Figure 3A shows in a diagram 300 the absorption 302 in arbitrary units of light as a function of its wavelength 304 by a light-scattering layer 104 with CdSe quantum dots of different sizes (2.4 nm to 3.7 nm; see Figure 3). Fig. 3B) and thus different emission (306: 500 nm; 308: 525 nm; 310: 550 nm; 312: 575 nm; 314: 600 nm; 316: 625 nm).

[0084] In various embodiments, the quantum dots are designed as described in Demir et al. “Quantum dot integrated LEDs using photonic and excitonic color conversion” Nano Today (2011) 6, 632-647, or are quantum dots described therein, to which reference is made here.

[0085] Fig. 3B shows in a diagram 320 the normalized intensity 322 in arbitrary unit of the light in the light-scattering layer made of Fig. 3A of the absorption (line starting on the left) and the Stokes-shifted emission (peak-shaped line) of the quantum dots. The respective mean diameter of the quantum dots is shown next to the respective absorption graphs. From the Fig. 3A and Fig. Figure 3B shows the narrowband emission and small Stokes shift of the emitted light. Furthermore, the overlap of the absorption and emission spectra is evident. This demonstrates that, unlike conventional fluorescent or phosphorescent dyes, the emitted light of the quantum dots exhibits approximately the same color valence as the absorbed light.

[0086] Fig.Figure 4 shows a flowchart of a process 500 for manufacturing a light-emitting component, for example the light-emitting component described above.

[0087] The process 400 features the formation 410 of an organically functional layer structure 108, which is formed to emit a first light 116.

[0088] Furthermore, the method 400 comprises the formation 420 of a light-scattering layer 104 with a plurality of quantum dots 114. The light-scattering layer 104 is arranged in the beam path of at least a portion of the emittable light of the organically functional layer structure 108. The quantum dots 114 are configured to absorb a second light in a first wavelength range and to emit at least a portion of the absorbed light in a second wavelength range, wherein the color valence of the second wavelength range corresponds approximately to the color valence of the first wavelength range.

[0089] The light-scattering layer with the quantum dots can be formed using a contactless method, for example wet chemically from a solution or paste.

[0090] The invention is not limited to the specified embodiments. For example, the light-emitting component can comprise several or a plurality of light-emitting components and / or light-scattering layers. REFERENCE MARK LIST 100 light-emitting components 102 Substrat 104 light-scattering layer 106 first electrode layer 108 organically functional layer structure 110 second electrode layer 112 Encapsulation structure 114 quantum dots 116, 118 light 130 active area 16 first contact section 18 second contact section 20 first electrode 21 electrical insulation barrier 24 Encapsulation layer 32 first contact area 34 second contact area 36 Adhesive layer 38 Cover bodies 300, 310 diagram 302 Absorption 304 wavelength 306, 308, 310, 312, 314, 316 light-emitting layers with different quantum dots 322 Intensity 400, 410, 420 process steps 500 diagram 502 Transmission 504 wavelength 506, 508, 510, 512, 514, 516, 518 light-scattering layers with scattering particles of different diameters

Claims

[1] Light-emitting component comprising: • an organically functional layered structure (108) designed to emit a first light (116), and • a light-scattering layer (104) with a multitude of quantum dots (114), • wherein the light-scattering layer (104) is arranged in the beam path of at least a part of the emittable light of the organically functional layer structure (108); wherein the quantum dots (114) are configured to absorb a second light in a first wavelength range and to emit at least a part of the absorbed light in a second wavelength range, wherein the color valence of the second wavelength range is approximately equal to the color valence of the first wavelength range, wherein the first light (116) and the second light have an essentially the same wavelength range, wherein the quantum dots (114) have a mean diameter of less than 100 nm, wherein the quantum dots (114) are essentially configured to be non-refracting and / or non-reflective for visible light, wherein the light-scattering layer (104) further comprises a matrix wherein the quantum dots (114) are embedded in the matrix, and wherein the matrix comprises an electrically conductive material. [2] Light-emitting component according to claim 1, wherein the second wavelength range has a full width at half maximum (FWHM) of 75 nm. [3] Light-emitting component according to one of claims 1 or 2, wherein the matrix is ​​essentially colorless and transparent. [4] Light-emitting component according to any one of claims 1 to 3, further comprising a mirror structure, wherein the mirror structure is arranged in the beam path of the first light (116) and / or the second light and has a reflectivity of at least 80% with respect to the first light (116) and / or the second light. [5] Light-emitting device according to any one of claims 1 to 4, wherein the light-scattering layer (104) has a thickness that is less than a mean free path of the first light (116) in the light-scattering layer (104) with respect to the quantum dots (114). [6] Light-emitting component according to any one of claims 1 to 5, further comprising an encapsulation structure (112), wherein the encapsulation structure (112) is configured to encapsulate at least the organic functional layer structure (108) and the light-scattering layer (104), wherein the encapsulation structure (112) is substantially hermetically sealed with respect to water and / or oxygen. [7] Light-emitting component according to any one of claims 1 to 6, further comprising a substrate (102), wherein the light-scattering layer (104) is arranged on or above the substrate (102), and the organic functional layer structure (108) is arranged on or above the light-scattering layer (104). [8] Light-emitting component according to claim 7, wherein the substrate (102) is substantially transparent to visible light and the first light (116) is emittable through the substrate (102). [9] Light-emitting component according to any one of claims 1 to 8, further comprising a substantially transparent electrode (106) for energizing the organic functional layer structure (108), wherein the transparent electrode (106) is arranged between the light-scattering layer (104) and the organic functional layer structure (108). [10] Light-emitting component according to any one of claims 1 to 8, wherein the organic functional layer structure (108) comprises the light-scattering layer (104). [11] Method (500) for manufacturing a light-emitting component, comprising the method: • Forming (510) an organically functional layered structure (108) which is formed to emit a first light (116), and • Forming (520) a light-scattering layer (104) with a multitude of quantum dots (114), • wherein the light-scattering layer (104) is arranged in the beam path of at least a part of the emittable light of the organically functional layer structure (108); • wherein the quantum dots (114) are configured to absorb a second light in a first wavelength range and to emit at least a part of the absorbed light in a second wavelength range, wherein the color valence of the second wavelength range is approximately equal to the color valence of the first wavelength range, wherein the first light (116) and the second light have an essentially the same wavelength range, wherein the quantum dots (114) have a mean diameter of less than 100 nm, wherein the quantum dots (114) are essentially configured to be non-refracting and / or non-reflective for visible light, wherein the light-scattering layer (104) further comprises a matrix wherein the quantum dots (114) are embedded in the matrix, and wherein the matrix comprises an electrically conductive material.

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