DE102016102939A1 - Light-emitting component and method for producing a light-emitting component - Google Patents

Abstract

In various exemplary embodiments, a light-emitting component is provided, comprising at least one light-emitting layer, a scattering layer (120) arranged in the beam path of the light-emitting layer, and a mirror structure arranged behind the light-emitting layer with respect to a main emission direction of the light-emitting component (100, 200, 300, 310) (130), wherein the mirror structure (130) is at least partially transmissive to the light (152) which can be emitted by the at least one light-emitting layer and at least partially reflective to the light (144) incident on the light-emitting component (100, 200, 300, 310). is trained.

Description

In various embodiments, a light emitting device and a method of manufacturing a light emitting device are provided.

An organic opto-electronic device, such as an OLED, may include an anode and a cathode having an organic functional layer system therebetween. The organic functional layer system may include one or more emitter layers in which electromagnetic radiation is generated, one or more charge carrier pair generation layer structures each of two or more charge generating layers (CGL) Charge pair generation, and one or more electron block, also referred to as hole transport layer (HTL), and one or more Lochblockadeschichten, also referred to as electron transport layer (s) (ETL) to the To direct current flow.

So far, there are two approaches for increasing the light output from the organic optoelectronic device: the external coupling and the internal coupling.

Internal decoupling may be understood to mean devices in which light is coupled out which is guided in the electrically active region of the optoelectronic component, for example the organic functional layer structure and / or the electrodes, i. the transparent, electrically conductive oxide layers (transparent conductive oxides - TCO). In other opto-electronic devices, i. not for organic light emitting devices, several technological approaches are known.

In a conventional device for the internal decoupling of light, a grid with a low refractive index can be applied to or over one of the electrodes of the optoelectronic component, for example an electrode made of indium tin oxide (ITO). The grating has structured regions with a low refractive index material.

In another conventional device for the internal decoupling of light, a scattering layer can be applied over or on an electrode, for example the indium tin oxide anode.

So far, the use of internal decoupling in organic light-emitting diodes, which are reflective in OFF state (OFF state), omitted, since the internal coupling or the structures for internal decoupling lead to a loss of specular OFF-state.

Known solutions to this problem are the use of switchable mirrors in front of the organic light emitting diode. Here, in the OFF state of the organic light emitting diode, a switchable mirror is connected in front of the organic light emitting diode, thus concealing the milky appearance of the organic light emitting diodes.

In various embodiments, a light-emitting device and a method of manufacturing a light-emitting device with which it is possible to provide an organic light-emitting diode that combines the advantages of internal coupling with the advantages of a specular OFF-state are provided. Such a designed organic light emitting diode allows, for example, a specular OFF-state with a color glimmer, which corresponds to the emitter color.

In various embodiments, a light emitting device is provided. The light-emitting component has at least one light-emitting layer, a scattering layer arranged in the beam path of the light-emitting layer, and a mirror structure arranged behind the light-emitting layer with respect to a main emission direction of the light-emitting component. The mirror structure is at least partially transmissive to the light that can be emitted by the at least one light-emitting layer and at least partially reflective to the light incident on the light-emitting component.

A main emission direction of a light-emitting device is a direction in which the emission of the light-emitting device is designed. That is, the direction of parasitically or unintentionally scattered light is not a major direction. In a main direction, a substantial portion of the total light emitted from the light emitting device is emitted.

The scattering layer can also be referred to as an internal outcoupling layer. The scattering layer has particles embedded in a matrix, for example, which have a scattering or refractive effect on the light which can be emitted by the light-emitting layer. By means of the scattering layer, light with a higher intensity can be coupled out of the light-emitting component than in a comparable light-emitting component without such a scattering layer.

Illustratively, the mirror structure is arranged behind the light-emitting layer with respect to the main emission direction. The scattering layer may be arranged in front of or behind the light-emitting layer with respect to the main emission direction.

Furthermore, the mirror structure is arranged in front of the light-emitting layer with respect to the light incident on the light-emitting component. For example, the light incident on the light-emitting device is incident on the light-emitting device from the direction opposite to the main emission direction. This direction may correspond to the viewing direction of the light emitting device in the OFF state (OFF state of the light emitting device). The scattering layer can be arranged in front of or behind the light-emitting layer in this regard.

This makes it possible to form a light-emitting component with a scattering layer which is optimized as an internal coupling-out structure for the light which can be emitted by the light-emitting layer. In this case, the light emitting device in the OFF state, i. in the de-energized state, by means of the mirror structure has a reflective appearance. In other words: in the off state, the mirror structure is visible and not the litter layer.

By integrating such a semitransparent mirror structure with, for example, a high transmission in the red spectral range and a high reflectivity in the blue and / or ultraviolet spectral range can be dispensed with in the integration of the light emitting device in a lamp to an additional UV protection in the lamp, as the UV protection is integrated by means of the mirror structure in the light emitting device. As a result, the light-emitting component is intrinsically protected against UV aging.

In a further development, the light-emitting component has on a carrier a first electrode and a second electrode arranged above the first electrode, the light-emitting layer being arranged between the first electrode and the second electrode.

In a further development, the carrier is designed to be translucent and at least one main emission direction of the light-emitting component is directed by the light-emitting layer through the carrier.

In a further development, the mirror structure has a transparency for the light which can be emitted by the light-emitting layer which is greater than 80%, for example greater than 90%. Alternatively or additionally, the transparency in at least one wavelength range of the emissive light is greater than 80%, for example greater than 90%. In other words, the transparency is at least partially, i. for at least one wavelength range, greater than 80%, for example greater than 90%. The transparency refers to the wavelength, the bandwidth or the one or more wavelength range of the light that is emitted or emitted by the at least one light-emitting layer in the regular operation of the light-emitting component.

In a further development, the mirror structure has a reflectivity for the light incident on the light-emitting component which is greater than 80%, for example greater than 90%. Alternatively or additionally, the reflectivity in at least one wavelength range of the emissive light is greater than 80%, for example greater than 90%. In other words, the reflectivity is at least partially, i. for at least one wavelength range, greater than 80%, for example greater than 90%. The reflectivity refers to the wavelength, the bandwidth or the one or more wavelength range of the light that is not emitted or emitted by the at least one light-emitting layer in the regular operation of the light-emitting component.

In a further development, the mirror structure is or has a Bragg mirror. The Bragg mirror has one or more layer sequences, wherein a layer sequence has at least two layers with different refractive indices. The mirror structure may be formed dielectrically or electrically conductive.

In a further development, the mirror structure is monolithically integrated in the light-emitting component.

This allows a compact design and protection of the mirror structure and their optical properties against component-external, harmful substances such as water, oxygen and / or solvents.

In a further development, the mirror structure is formed on the side of the carrier, which faces away from the light-emitting layer. In other words, the mirror structure is formed on the surface of the support of the light-emitting device. Thereby, a light-emitting device having a high-quality appearance can be realized.

In a further development, the light-emitting component has a cover which is formed over the light-emitting layer, wherein at least one main emission direction of the light-emitting component is directed by the light-emitting layer through the cover substrate. Illustratively, the light-emitting component is thus a top emitter or a bi- or omnidirectionally emitting component. As a result, different concepts regarding the energization of the light-emitting component are made possible, for example a wide selection of electrode materials, connections and the like.

In a further development, the mirror structure is designed as a cover or has these. This allows a technically simple integration of the mirror structure in existing process and designs, as well as a technically simple encapsulation.

In a further development, the mirror structure is formed on the side of the cover, which faces away from the light-emitting layer. In other words, the mirror structure is formed on the surface of the cover of the light-emitting device. Thereby, a light-emitting device having a high-quality appearance can be realized.

In a further development, the light-emitting component has at least one first light-emitting layer and at least one second light-emitting layer arranged in the beam path of the first light-emitting layer.

The mirror structure may be transparent to the emissive light of the first light-emitting layer and / or to the emissive light of the second light-emitting layer.

Light of a different color than that for which the mirror structure is impermeable can be conducted in the light-emitting component, that is to say not decoupled. In this combination, for example, the emission of a specific wavelength range from the light-emitting component can be achieved and the dominant wavelength can be set in a small distribution for a plurality or many of the light-emitting components. In a further development, the first light-emitting layer is an electroluminescent layer and the second light-emitting layer is a conversion layer, which is optically excitable by means of the emissive light of the first light-emitting layer.

In a mirror structure which is transparent to the light of the conversion layer and opaque to the light of the electroluminescent first light-emitting layer, this makes it possible, for example, blue light, which is used in organic light emitting diodes for generating, for example, green light, does not leave the organic light emitting diode ,

In a further development, the first light-emitting layer has a first, electroluminescent material and the second light-emitting layer has a second electroluminescent material.

In various embodiments, a method of manufacturing a light-emitting device is provided. The method comprises forming at least one light-emitting layer, forming a scattering layer arranged in the beam path of the light-emitting layer, and forming a mirror structure arranged with respect to a main emission direction of the light-emitting device behind the light-emitting layer. The mirror structure is formed at least partially permeable to the light that can be emitted by the at least one light-emitting layer and at least partially reflective to the light incident on the light-emitting component.

The order of the steps may be varied depending on the specific embodiment. For example, the light-emitting layer can be formed on the scattering layer or vice versa. Furthermore, for example, the mirror structure can be formed on a support on which the scattering layer and the light-emitting layer are subsequently formed. Alternatively, the mirror structure may be formed after the light-emitting layer and / or the scattering layer have been formed.

Embodiments of the invention are illustrated in the figures and are explained in more detail below.

Show it

1 a schematic cross-sectional view of a light-emitting device according to various embodiments;

2 a schematic cross-sectional view of a light-emitting device according to various embodiments;

3A FIG. 5B are schematic cross-sectional views of a light emitting device according to various embodiments; FIG.

4 a schematic cross-sectional view of a light-emitting device according to various embodiments; and

5 a flowchart of a method of manufacturing a light-emitting device according to various embodiments.

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology such as "top", "bottom", "front", "back", "front", "rear", etc. is used with reference to the orientation of the described figure (s). Because components of embodiments can be positioned in a number of different orientations, the directional terminology is illustrative and is in no way limiting. It should be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. It should be understood that the features of the various exemplary embodiments described herein may be combined with each other unless specifically stated otherwise. The following detailed description is therefore not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.

As used herein, the terms "connected," "connected," and "coupled" are used to describe both direct and indirect connection, direct or indirect connection, and direct or indirect coupling. In the figures, identical or similar elements are provided with identical reference numerals, as appropriate.

According to various embodiments, the light emitting device (e.g., an organic light emitting device such as OLED) may be implemented as a bottom emitter.

As used herein, the term "bottom emitter" or "bottom emitting light emitting device" refers to an embodiment that is transparent to the substrate side of the light emitting device. For example, for this purpose at least the substrate and layers formed between the substrate and the at least one functional layer (for example an electrode (base electrode) formed between the substrate and the functional layer (s)) may be made transparent. Accordingly, a light emitting device implemented as a bottom emitter may emit, for example, radiation generated in the functional layers (e.g., organic functional layers in an organic light emitting device such as an OLED) on the substrate side of the light emitting device.

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

As used herein, the term "top emitter" or "top emitting light emitting device" refers, for example, to an embodiment that is transparent to the side facing away from the substrate (in other words, to the top side) of the light emitting device. In particular, the electrodes (cover electrode), barrier thin film, intermediate layer, cover layer formed on or above the at least one functional layer of the light-emitting component (eg between functional layer (s) and barrier thin film) can be made transparent. Accordingly, a light-emitting component designed as a top emitter can emit, for example, radiation generated in the functional layers (eg organic functional layers in the case of an organic light-emitting component such as an OLED) on the top side of the light-emitting component.

A light emitting device configured as a top emitter according to various embodiments can advantageously have a high light output and a very low angular dependence of the radiation density.

A combination of bottom emitter and top emitter is also provided in various embodiments. In such an embodiment, the light-emitting component is generally capable of producing the light generated in the functional layers (eg the organic functional layers in the case of an organic light-emitting component such as an OLED) in both directions - that is to both the substrate side and the cover side - to emit (transparent or translucent OLED).

By way of example, a light-emitting component which has two flat, optically active sides can be made transparent or translucent in the connecting direction of the optically active sides, for example as a transparent or translucent organic light-emitting diode. A planar light emitting device may also be referred to as a planar light emitting device.

However, the optically active region can also have a planar, optically active side and a flat, optically inactive side, for example an organic light-emitting diode which is set up as a so-called top emitter or bottom emitter. The optically inactive side may be transparent or translucent in various embodiments, or be provided with a mirror structure and / or an opaque substance or mixture of substances, for example for heat distribution. The beam path of the light-emitting component may be directed, for example, on one side.

The first electrode, the second electrode and the organic functional layer structure can each have a large area. As a result, the light-emitting component can have a coherent luminous area which is not structured into functional subareas, for example a luminous area segmented into functional areas or a luminous area formed by a plurality of pixels. As a result, a large-area radiation of electromagnetic radiation from the light-emitting component can be made possible. "Large area" can mean that the optically active side has an area, for example a contiguous area, for example greater than or equal to a few square millimeters, for example greater than or equal to one square centimeter, for example greater than or equal to one square decimeter. By way of example, the light-emitting component can have only a single contiguous luminous surface, which is brought about by the large-area and contiguous formation of the electrodes and the organic functional layer structure.

A light emitting device according to various embodiments can be advantageously used for lighting, such as room lighting.

In the context of this description, a scatter layer can be understood as a layer that is set up for internal decoupling. For internal decoupling, for example, electromagnetic radiation, for example light, which is conducted in the electrically active region of the light-emitting component, for example the organic functional layer structure and / or the electrodes, i. the transparent, electrically conductive oxide layers (transparent conductive oxides - TCO).

1 shows a schematic cross-sectional view of a light-emitting device according to various embodiments.

In various embodiments, a light emitting device 100 provided. The light emitting device 100 has at least one light-emitting layer, a scattering layer arranged in the beam path of the light-emitting layer 120 , and one relating to a main emission direction 154 of the light emitting device 100 arranged behind the light-emitting layer mirror structure 130 on.

The at least one light-emitting layer has, for example, an electroluminescent material, also referred to as emitter material. The at least one light-emitting layer is formed, a light 150 to emit. The at least one light-emitting layer is designed such that the emissive light has only a narrow part of the visible light spectrum, that is, has only a narrow bandwidth or a narrow wavelength range, for example, one or more wavelength range, each for itself or one width in a range of about 5 nm to about 100 nm. For essentially these bandwidths or wavelength ranges of visible light, the mirror structure is permeable, that is to say transmissive, formed, and reflective or absorbing for other or different wavelength ranges.

The at least one light-emitting layer is, for example, in an organically functional layer structure of the light-emitting component 100 arranged or formed, as will be described in more detail below. The organic functional layer structure is between a first electrode and a second electrode 23 arranged (in 1 are the organic functional layer structure and the first electrode as a layer 110 illustrated). At least one of the electrodes is transparent to the light which can be emitted by the at least one light-emitting layer.

The litter layer 120 is formed in the beam path of the at least one light-emitting layer, for example between the at least one light-emitting layer and the carrier 12 , light 150 , of which the at least one light-emitting layer is emissive, is in the scattering layer 120 scattered (in 1 illustrated by the arrows 146 ). A part 148 of the scattered light 146 is backscattered in the direction of the at least one light emitting layer. In this respect, by means of the litter layer 120 the radiation ratio of the light-emitting device can be adjusted, for example, in a bi- or omnidirectional, light-emitting device, for example by the first electrode and the second electrode 23 are transparent. In various embodiments, the litter layer 120 between the first electrode and the second electrode 23 arranged. Alternatively, the litter layer 120 between the first electrode and the carrier 12 or disposed on or above the second electrode.

In a light emitting device 100 with a highly reflective second electrode 23 , For example, a reflective second electrode 23 , For example, a second electrode 23 made of a metal, is the backscattered share 148 of the scattered light 146 at the second electrode 23 in the direction of the at least one main emission direction 154 diverted. In this respect, the light which can be emitted by the at least one light-emitting layer can be emitted 152 a proportion of backscattered light 148 exhibit.

The mirror structure 130 is at least partially transparent to the light which can be emitted by the at least one light-emitting layer 152 , The mirror structure 130 has, for example, a transparency for the light which can be emitted by the light-emitting layer 152 greater than about 60%, for example greater than about 70%, for example greater than about 80%, for example greater than about 90%. As a result, the light-emitting component 100 Light that is or can be emitted in the at least one light-emitting layer, from the mirror structure 130 , which is located in the beam path of the main emission direction in front of the at least one light-emitting layer, are coupled out.

For example, the mirror structure 130 between the at least one light-emitting layer and the carrier 12 arranged, with emissive light 152 from the light-emitting layer through the support 12 which is also a main emission direction of the light-emitting device 100 according to various embodiments.

Additionally or alternatively, the mirror structure 130 between the litter layer 120 and the carrier 12 be arranged (illustrated in 1 ). In various embodiments, the carrier 12 transparent. At least one main emission direction 154 of the light emitting device is from the light emitting layer through the carrier 12 directed.

A part of the light which can be emitted by the at least one light-emitting layer 152 can from the mirror structure 130 and / or the wearer 12 reflected and / or absorbed. In this respect, the light which can be emitted by the light-emitting component can be used 154 a lower intensity and / or another Have wavelength spectrum as the light emitted from the at least one light-emitting layer light 152 ,

Furthermore, the mirror structure 130 at least partially reflective to the light emitting device 100 incident light 144 educated. This turns the incident light 144 reflected at the mirror structure at least partially (illustrated by means of the arrow 142 ). The mirror structure 130 has, for example, a reflectivity for the light incident on the light-emitting component 144 greater than about 60%, for example greater than about 70%, for example greater than about 80%, for example greater than about 90%.

For example, the mirror structure 130 a high reflectivity for light having a wavelength different from the emissive light of the at least one light emitting layer. The light which can be emitted by the at least one light-emitting layer relates to the light which can be emitted in the regular operation of the light-emitting component. In a light-emitting device having an electroluminescent light-emitting layer comprising, for example, a dye, the light which can be emitted in regular operation and which is light-emitting or emitted by the dye after application of the operating current.

Clearly, light of a first wavelength, which is emitted in the light-emitting layer, that is to say generated, propagates through a scattering layer optimized for this first wavelength 120 , Optically following, that is with respect to the main emission direction in the beam path behind the scattering layer or with respect to a light incident on the light-emitting device in front of the light-emitting layer and the scattering layer, is a mirror structure 130 arranged, which is translucent for the first wavelength. Furthermore, the mirror structure 130 is formed such that it is impermeable to light, for example, visible light having a wavelength different from the first wavelength.

In addition, the first wavelength can be, for example, a wavelength with a line width, a coherent wavelength range or multiple wavelength ranges.

By means of the described embodiment of the light-emitting component, it is possible to have a light-emitting component with a scattering layer 120 to produce as an internal coupling-out structure, which has a reflective appearance in the off state, ie in the de-energized state, by means of the mirror structure.

That is, by this arrangement of litter layer 120 and mirror structure 130 For example, it is possible to provide a light emitting device that combines the advantages of internal outcoupling with those of a specular OFF state. Such a designed light-emitting device has a specular OFF-state with a color glimmer, which corresponds to the emitter color.

In various embodiments, the mirror structure 130 a layered structure. For example, the mirror structure 130 a Bragg mirror or has such a. In other words: the mirror structure 130 may be formed as an optical bandpass filter which is transparent to light which can be emitted by the light-emitting layer and is impermeable to light incident on the light-emitting component from outside, for example except for the fraction of the emissive light.

wobei n₀ der Brechungsindex des Umgebungsmediums ist, n₁ und n₂ die Brechungsindizes der, beispielsweise, beiden Materialien der Schichten der Spiegelstruktur und n_S der Brechungsindex des Trägers sind. N ist die Anzahl der Schichtpaare mit den Brechungsindizes n₁, n₂ der Spiegelstruktur 130. Die Schichten dieser Spiegelstruktur können beispielsweise herkömmliche, dielektrische Schichten sein, beispielsweise keramische Schichten, beispielsweise aus einem Metalloxid, Metallnitrid oder Metalloxinitrid, beispielsweise Titandioxid und Siliziumdioxid. At one the mirror structure 130 , which is formed as a Bragg mirror, the mirror structure has a plurality or many layers stacked on top of one another with alternating optical properties, for example different refractive indices. This results in the maximum reflectivity for a wavelength when all layers have an optical thickness of exactly one quarter of the wavelength. Then the reflectivity R for this wavelength is calculated to be:

where n _{0 is} the refractive index of the surrounding medium, n ₁ and n _{2 are} the refractive indices of, for example, both materials of the layers of the mirror structure and n _{S is} the refractive index of the carrier. N is the number of layer pairs with refractive indices n ₁ , n _{2 of} the mirror structure 130 , The layers of this mirror structure may be, for example, conventional dielectric layers, for example ceramic ones Layers, for example of a metal oxide, metal nitride or metal oxynitride, for example titanium dioxide and silicon dioxide.

Alternatively, the layers of the mirror structure may be formed of transparent conductive oxides (TCOs). This makes it possible to form an electrically conductive mirror structure based on a Bragg mirror.

wobei λ₀ die mittlere Wellenlänge des Bandes ist, beispielsweise die oben beschriebene erste Wellenlänge ist. The width Δλ _{0 of} the stopband for this mirror structure 130 calculated according to:

where λ _{0 is} the mean wavelength of the band, for example, the first wavelength described above.

By increasing the number N of layer pairs, the reflectivity R of the mirror structure can be increased. By increasing the refractive index difference of the layers (n ₁ -n ₂ ) of the layer sequence of the mirror structure 130 the reflectivity and the bandwidth can be increased.

In various embodiments, the mirror structure is 130 between the first electrode and the carrier 12 arranged. Alternatively, the mirror structure 130 between the litter layer 120 and the carrier 12 arranged. Alternatively, the mirror structure 130 between the first electrode and the second electrode 23 arranged. Alternatively, the mirror structure 130 on the side of the carrier 12 formed facing away from the light-emitting layer. In various embodiments, the first electrode or the second electrode 23 a part of the mirror structure 130 ,

In various embodiments, the mirror structure is 130 monolithically integrated in the light emitting device. In other words: the mirror structure 130 and the electrically active region, ie the electrodes and the at least one light-emitting layer, are arranged within a common encapsulation structure, for example surrounded by it.

In various embodiments, the light-emitting device has a cover formed over the light-emitting layer. The mirror structure 130 may in this case on or above the second electrode 23 , for example, between the second electrode 23 and the cover or on the cover. Alternatively, the mirror structure 130 as a cover 38 trained or has this. Alternatively, the mirror structure 130 on the side of the cover 38 formed facing away from the light-emitting layer.

In the event that the second electrode 23 is formed transparent, at least one main emission direction of the light emitting device from the at least one light emitting layer in the direction of the second electrode 23 and be directed through the second electrode and the optional cover.

In various embodiments, the light emitting device 100 at least one first light-emitting layer and at least one second light-emitting layer arranged in the beam path of the first light-emitting layer. For example, the first light-emitting layer is an electroluminescent layer and the second light-emitting layer is a conversion layer that is optically excitable by means of the emissive light of the first light-emitting layer. In other words, the conversion layer has a phosphor by means of which the wavelength of the emissive light of the first light-emitting layer can be converted.

Forming electromagnetic radiation of a second wavelength from electromagnetic radiation of a first wavelength is called wavelength conversion. Wavelength conversion can be realized by means of a phosphor. In the context of this description, a substance can be understood as the luminescent material which converts electromagnetic radiation of one wavelength loss loss into electromagnetic radiation of other wavelengths, for example longer wavelength (Stokes shift) or shorter wavelength (anti-Stokes shift), for example by means of phosphorescence or fluorescence. Conventional phosphors are, for example, garnets or nitrides, silicates, nitrides, oxides, phosphates, borates, oxynitrides, sulfides, selenides, aluminates, tungstates, and halides of aluminum, silicon, magnesium, calcium, barium, strontium, zinc, cadmium, manganese, indium, Tungsten and other transition metals, or rare earth metals such as yttrium, gadolinium or lanthanum, with an activator such as copper, silver, Aluminum, manganese, zinc, tin, lead, cerium, terbium, titanium, antimony or europium. In various embodiments, the phosphor may be an oxidic or (oxi-) nitride phosphor such as garnet, orthosilicate, nitrido (alumo) silicate, nitride or nitrido orthosilicate, or a halide or halophosphate. Specific examples of suitable phosphors are Strontiumchloroapatit: Eu ((Sr, Ca) ₅ (PO _{4) 3} Cl: Eu; SCAP), yttrium-aluminum-Grant: Ce (YAG: Ce) or CaAlSiN _3: Eu. Furthermore, particles with light-scattering properties and / or auxiliaries may be contained in the phosphor or phosphor mixture, for example. Examples of adjuvants include surfactants and organic solvents. Examples of light scattering particles are gold, silver and metal oxide particles. For example, a phosphor may include Ce ³⁺ doped garnets such as YAG: Ce and LuAG, for example, (Y, Lu) ₃ (Al, Ga) ₅ O ₁₂ : Ce ³⁺ ; Eu ²⁺ doped nitrides, for example CaAlSiN ₃ : Eu ²⁺ , (Ba, Sr) ₂ Si ₅ N ₈ : Eu ²⁺ ; Eu ²⁺ doped sulfdides, SIONe, SiAlON, orthosilicates, for example (Ba, Sr) ₂ SiO ₄ : Eu ²⁺ ; Chlorosilicates, chlorophosphates, BAM (barium magnesium aluminate: Eu) and / or SCAP, halophosphate or be formed therefrom.

Alternatively or additionally, the first light-emitting layer has a first, electroluminescent material and the second light-emitting layer has a second, electroluminescent material.

In various embodiments, the litter layer 120 embedded particles in a matrix. The particles and the matrix have a refractive index difference of at least 0.05 in the wavelength range of the light that can be emitted by the at least one light-emitting layer.

In various embodiments, the litter layer 120 a mean refractive index greater than or equal to the refractive index of further layers of the layer 110 on.

In various embodiments, the litter layer 120 an average refractive index of at least about 1.5, for example a refractive index of at least about 1.6, for example a refractive index of at least about 1.65, for example a range of about 1.7 to about 2.1.

In various embodiments, the litter layer 120 a thickness in a range of about 1 μm to about 100 μm, for example in a range of about 10 μm to about 100 μm, for example about 25 μm.

In various embodiments, the matrix has the litter layer 120 a refractive index greater than about 1.7.

In various embodiments, the matrix is the litter layer 120 amorphous formed. For example, the matrix comprises or is formed of an inorganic glass or a plastic. In various embodiments, the matrix comprises or is formed from one of the following: a silicone, for example polydimethylsiloxane, polydimethylsiloxane / polydiphenylsiloxane; a silazane, an epoxy, a polyacrylate, a polycarbonate or the like, for example a silicone hybrid, a silicone-epoxy hybrid.

The particles of the litter layer 120 For example, have one of the following geometric shapes and / or part of one of the following geometric shapes: spherical, aspherical, for example prismatic, ellipsoidal, hollow, compact, platelet or rod-shaped.

For example, the particles have a mean grain size in a range of about 0.05 μm to about 10 μm, for example in a range of about 0.1 μm to about 1 μm.

As light-scattering particles the litter layer 120 For example, dielectric scattering particles may be provided, for example, a metal oxide, for example silicon oxide (SiO 2), zinc oxide (ZnO), zirconium oxide (ZrO 2), indium tin oxide (ITO) or indium zinc oxide (IZO), gallium oxide (Ga 2 O x). Alumina, or titania. Other particles may also be suitable, provided that they have a refractive index that is equal to the effective refractive index of the matrix of the scattering layer 120 is different, for example, air bubbles, acrylate, or glass bubbles. Furthermore, for example, metallic nanoparticles, metals such as gold, silver, iron nanoparticles, or the like may be provided as light-scattering particles.

In various embodiments, a mirror structure 130 reflect electromagnetic radiation. A mirror structure may be formed in various embodiments as an optical grating, a metallic mirror, a photonic crystal or a totally reflecting interface. A mirror structure may be completely or partially reflective for electromagnetic Radiation of a wavelength range, for example, as a partially transparent mirror structure, for example as a dichroic mirror. The semitransparent mirror structure may be, for example, a divider mirror and / or a disposable mirror. For example, the partially transmissive mirror structure may reflect a portion of the electromagnetic radiation incident thereon and the other portion of the incident electromagnetic radiation may pass through the partially transmissive mirror structure. The partially transparent mirror structure may, for example, on one side a dielectric layer system and / or optionally on the other side a reflection-reducing coating, for example, to avoid double images. Alternatively or in addition to the dielectric layer system, for example, a very thin metal coating can also be used.

2 shows a schematic cross-sectional view of a light emitting device according to various embodiments, which may correspond substantially to one of the embodiments shown above.

At the in 2 illustrated embodiment of a light-emitting device is, in contrast to in 1 illustrated embodiment - the litter layer 120 between the second electrode 23 and the light-emitting layer, for example, in an organic functional layer structure described in more detail below (in FIG 2 together with the first electrode as a layer 110 illustrated). The litter layer 120 is formed, for example, electrically conductive. For example, the scattering layer comprises electrically conductive particles and / or an electrically conductive matrix in which the particles are embedded, wherein the matrix and the particles have a refractive index difference of more than 0.05 and the particles have an average diameter of at least approximately one fourth of the Wavelength of the light which can be emitted by the at least one light-emitting layer and has the smallest wavelength in the visible wavelength range (with the naked eye). The electrically conductive particles and / or the electrically conductive matrix can be formed, for example, from different electrically conductive, transparent oxides (TCO).

3A , B show schematic cross-sectional views of a light emitting device according to various embodiments, which may correspond substantially to one of the embodiments presented above.

At the in 3A illustrated embodiment of a light-emitting device is, in contrast to in 2 illustrated embodiment - the mirror structure 130 on the side of the carrier 12 arranged facing away from the light-emitting layer. A part 302 of the light-emitting layer in the carrier 12 emitted light 152 can at the mirror structure 130 be scattered back or reflected.

At the in 3B illustrated embodiment of a light-emitting device is, in contrast to in 1 illustrated embodiment - the mirror structure 130 on the side of the carrier 12 arranged facing away from the light-emitting layer.

4 shows a schematic cross-sectional view of a light emitting device according to various embodiments, which may correspond substantially to one of the embodiments shown above, wherein the mirror structure and the scattering layer in 4 not illustrated.

On the carrier 12 an optoelectronic layer structure is formed. The optoelectronic layer structure has a first electrode layer 14 on that a first contact section 16 , a second contact section 18 and a first electrode 20 having.

Between the carrier 12 and the first electrode layer 14 For example, a first barrier layer (not shown), for example a first barrier thin layer, may be formed.

The carrier 12 can be translucent or transparent. The carrier 12 serves as a support for electronic elements or layers, for example light-emitting elements. The carrier 12 For example, plastic, metal, glass, quartz and / or a semiconductor material can have or be formed from it. Furthermore, the carrier can 12 comprise or be formed from a plastic film or a laminate with one or more plastic films. The carrier 12 can be mechanically rigid or mechanically flexible.

In various embodiments, the light emitting device 100 on or above the vehicle 12 a first electrode 20 for example, a first electrode layer; for example as a closed electrode layer; and one above the first electrode 20 arranged second electrode 23 , For example, a second electrode layer, for example, as a closed electrode layer on. The light-emitting layer is between the first electrode 20 and the second electrode 23 arranged.

The first electrode 20 is from the first contact section 16 by means of an electrical insulation barrier 21 electrically isolated. The second contact section 18 is with the first electrode 20 the optoelectronic layer structure electrically coupled. The first electrode 20 may be formed as an anode or as a cathode. The first electrode 20 can be translucent or transparent. The first electrode 20 has an electrically conductive material, for example, metal and / or a conductive conductive oxide (TCO) or a layer stack of several layers comprising metals or TCOs. The first electrode 20 For example, a layer stack may comprise a combination of 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 may alternatively or in addition to the materials mentioned:
Networks of metallic nanowires and particles, for example of Ag, networks of carbon nanotubes, graphene particles and layers and / or networks of semiconducting nanowires.

Above the first electrode 20 is an optically functional layer structure, for example an organic functional layer structure 22 , the optoelectronic layer structure formed. The organic functional layer structure 22 For example, it may have one, two or more sublayers. For example, the organic functional layer structure 22 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 and hole transport layer. In the hole transport layer, the hole conductivity is larger than the electron conductivity. The hole transport layer serves to transport the holes. In the electron transport layer, the electron conductivity is larger 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 22 one, two or more functional layer structure units, each having said sub-layers and / or further intermediate layers.

Over the organic functional layer structure 22 is a second electrode 23 of the optoelectronic layer structure, which is electrically connected to the first contact section 16 is coupled. The second electrode 23 may according to one of the embodiments of the first electrode 20 be formed, wherein the first electrode 20 and the second electrode 23 may be the same or different. The first electrode 20 serves, for example, as the anode or cathode of the optoelectronic layer structure. The second electrode 23 serves corresponding to the first electrode as the cathode or anode of the optoelectronic layer structure.

The optoelectronic layer structure is an electrically and / or optically active region. The active region is, for example, the region of the optoelectronic component 10 in which electrical current for operation of the optoelectronic component 10 flows and / or in which electromagnetic radiation is generated or absorbed. On or above the active area, a getter structure (not shown) may be arranged. The getter layer can be translucent, transparent or opaque. The getter layer may include or be formed of a material that absorbs and binds substances that are detrimental to the active area.

Above the second electrode 23 and partially over the first contact portion 16 and partially over the second contact portion 18 is an encapsulation layer 24 the optoelectronic layer structure is formed, which encapsulates the optoelectronic layer structure. The encapsulation layer 24 may be formed as a second barrier layer, for example as a second barrier thin layer. The encapsulation layer 24 can also be referred to as thin-layer encapsulation. The encapsulation layer 24 forms a barrier to chemical contaminants or atmospheric substances, in particular to water (moisture) and oxygen. The encapsulation layer 24 may be formed as a single layer, a layer stack or a layer structure. The encapsulation layer 24 may include or be formed from: alumina, zinc oxide, zirconia, titania, hafnia, tantalum lanthania, silica, silicon nitride, silicon oxynitride, indium tin oxide, indium zinc oxide, aluminum doped zinc oxide, poly (p-phenylene terephthalamide), nylon 66, and mixtures and alloys thereof , Optionally, the first barrier layer on the carrier 12 corresponding to a configuration of the encapsulation layer 24 be educated.

In the encapsulation layer 24 are above the first contact section 16 a first recess of the encapsulation layer 24 and over the second contact portion 18 a second recess of the encapsulation layer 24 educated. In the first recess of the encapsulation layer 24 is a first contact area 32 exposed and in the second recess of the encapsulation layer 24 is a second contact area 34 exposed. The first contact area 32 serves for electrically contacting the first contact section 16 and the second contact area 34 serves for electrically contacting the second contact section 18 ,

Above the encapsulation layer 24 is an adhesive layer 36 educated. The adhesive layer 36 has, for example, an adhesive, for example an adhesive, for example a laminating adhesive, a lacquer and / or a resin. The adhesive layer 36 For example, it may comprise particles which scatter electromagnetic radiation, for example light-scattering particles.

Over the adhesive layer 36 is a cover body 38 educated. The adhesive layer 36 serves to fasten the cover body 38 at the encapsulation layer 24 , The cover body 38 has, for example, plastic, glass and / or metal. For example, the cover body 38 may be formed essentially of glass and 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 optoelectronic device 1 , for example, from mechanical forces from the outside. Furthermore, the cover body 38 serve for distributing and / or dissipating heat, which in the conventional optoelectronic device 1 is produced. For example, the glass of the cover body 38 serve as protection against external influences and the metal layer of the cover body 38 can be used to distribute and / or dissipate during operation of the conventional optoelectronic device 1 serve arising heat.

An in 4 bottom side of the carrier 12 and one in 4 upper side of the cover body 38 form main surfaces of the optoelectronic component. The light-emitting component emits electromagnetic radiation, in particular light, via one or both main surfaces. The carrier 12 and the cover body 38 , optionally also the encapsulation layer 24 and the adhesive layer 36 , are on lateral side surfaces 48 of the optoelectronic component 10 flush formed. The optoelectronic component 10 may also be referred to as a monolithic, light-emitting device, for example as a monolithic OLED.

5 FIG. 12 shows a flow chart of a method of manufacturing a light-emitting device according to various embodiments.

In various embodiments, methods 500 for producing a light emitting device.

The procedure 500 has a training 510 at least one light emitting layer, forming 520 a scattering layer disposed in the optical path of the light-emitting layer, and forming 530 a mirror structure arranged behind the light emitting layer with respect to a main emission direction of the light emitting device.

The mirror structure is at least partially transmissive to the light that can be emitted by the at least one light-emitting layer and at least partially reflective to the light incident on the light-emitting component.

The invention is not limited to the specified embodiments. For example, a plurality of light-emitting components may be arranged on a common carrier one above the other or next to one another. Furthermore, the method can have features of the light-emitting component mutatis mutandis, and vice versa.

LIST OF REFERENCE NUMBERS

100, 200, 300, 310, 1

Light-emitting component

110

 first electrode and light-emitting layer

120

 scattering layer

130

 mirror structure

142, 144, 146, 148, 150, 152, 154

 light

12

carrier

14

first electrode layer

16

first contact section

18

second contact section

20

first electrode

21

electrical insulation barrier

22

organic functional layer structure

23

second electrode

24

encapsulation

32

first contact area

34

second contact area

36

Adhesive layer

38

covering

500

 method

510, 520, 530

 steps

Claims (15)

Light-emitting component ( 100 . 200 . 300 . 310 ) comprising: at least one light-emitting layer, a scattering layer arranged in the beam path of the light-emitting layer, 120 ), and • a with respect to a main emission direction of the light emitting device (FIG. 100 . 200 . 300 . 310 ) disposed behind the light-emitting layer mirror structure ( 130 ), Where the mirror structure ( 130 ) at least partially transmissive to the light which can be emitted by the at least one light-emitting layer ( 152 ) and at least partially reflective to the light-emitting device ( 100 . 200 . 300 . 310 ) incident light ( 144 ) is trained. Light-emitting component ( 100 . 200 . 300 . 310 ) according to claim 1, wherein the light-emitting component ( 100 . 200 . 300 . 310 ) on a support ( 12 ) a first electrode ( 20 ) and one above the first electrode ( 20 ) arranged second electrode ( 23 ), wherein the light-emitting layer between the first electrode ( 20 ) and the second electrode ( 23 ) is arranged. Light-emitting component ( 100 . 200 . 300 . 310 ) according to claim 2, wherein the carrier ( 12 ) is translucent and at least one main emission direction ( 154 ) of the light-emitting device from the light-emitting layer through the carrier ( 12 ). Light-emitting component ( 100 . 200 . 300 . 310 ) according to one of claims 1 to 3, wherein the mirror structure ( 130 ) a transparency for the light which can be emitted by the light-emitting layer ( 152 ), which is greater than 80%. Light-emitting component ( 100 . 200 . 300 . 310 ) according to one of claims 1 to 4, wherein the mirror structure ( 130 ) a reflectivity for the light emitting device ( 100 . 200 . 300 . 310 ) incident light ( 144 ), which is greater than 80%. Light-emitting component ( 100 . 200 . 300 . 310 ) according to one of claims 1 to 5, wherein the mirror structure ( 130 ) is or has a Bragg mirror. Light-emitting component ( 100 . 200 . 300 . 310 ) according to one of claims 1 to 6, wherein the mirror structure ( 130 ) monolithically in the light emitting device ( 100 . 200 . 300 . 310 ) is integrated. Light-emitting component ( 100 . 200 . 300 . 310 ) according to one of claims 2 to 7, wherein the mirror structure ( 130 ) is formed on the side of the carrier facing away from the light-emitting layer. Light-emitting component ( 100 . 200 . 300 . 310 ) according to one of claims 2 to 7, wherein the light-emitting component ( 100 . 200 . 300 . 310 ) a cover ( 38 ), which is formed over the light-emitting layer, wherein at least one main emission direction of the light-emitting component ( 100 . 200 . 300 . 310 ) from the light-emitting layer through the cover ( 38 ). Light-emitting component ( 100 . 200 . 300 . 310 ) according to claim 9, wherein the mirror structure ( 130 ) as a cover ( 38 ) is formed or has this. Light-emitting component ( 100 . 200 . 300 . 310 ) according to claim 9, wherein the mirror structure ( 130 ) on the side of the cover ( 38 ) is formed, which faces away from the light-emitting layer. Light-emitting component ( 100 . 200 . 300 . 310 ) according to one of claims 1 to 11, wherein the light-emitting component ( 100 . 200 . 300 . 310 ) has at least one first light-emitting layer and at least one arranged in the beam path of the first light-emitting layer second light-emitting layer. Light-emitting component ( 100 . 200 . 300 . 310 ) according to claim 12, wherein the first light-emitting layer is an electroluminescent layer and the second light-emitting layer is a conversion layer which is optically excitable by means of the emissive light of the first light-emitting layer. Light-emitting component ( 100 . 200 . 300 . 310 ) according to claim 12, wherein the first light-emitting layer comprises a first, electroluminescent material and the second light-emitting layer comprises a second electroluminescent material. Method for producing a light-emitting component ( 100 . 200 . 300 . 310 ), the method comprising: • forming ( 510 ) at least one light-emitting layer, 520 ) a scattering layer arranged in the beam path of the light-emitting layer ( 120 ), and • training ( 530 ) one concerning a main emission direction ( 154 ) of the light emitting device ( 100 . 200 . 300 . 310 ) disposed behind the light-emitting layer mirror structure ( 130 ), Where the mirror structure ( 130 ) at least partially transmissive to the light which can be emitted by the at least one light-emitting layer ( 152 ) and at least partially reflective to the light-emitting device ( 100 . 200 . 300 . 310 ) incident light ( 144 ) is formed.

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