Illumination unit, method for manufacturing illumination unit, conversion element for photoelectronic structural element, radiation source comprising LED and conversion element, light extraction structure and photoelectronic device

Abstract

To provide a photoelectronic device provided with an arrangement structure comprising a plurality of light sources for generating light.SOLUTION: An illumination unit comprises at least one photoelectron emitter unit (13) that emits electromagnetic radiation (19) through a light emission surface (15), and a photonic structure (17) that beam-shapes the electromagnetic radiation (19) before emitting the electromagnetic radiation (19) through the light emission surface (15), where the photonic structure (17) shapes the electromagnetic radiation (19) such that the electromagnetic radiation (19) has a specific far field (21).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] This patent application claims the priority of German Patent Application Publication No. 102019112639.8 dated May 14, 2019, of German Patent Application Publication No. 102019112616.9 dated May 14, 2019, of German Patent Application Publication No. 102019115991.1 dated June 12, 2019, of German Patent Application Publication No. 102019116313.7 dated June 14, 2019, of German Patent Application Publication No. 102019118251.4 dated July 5, 2019, and of the priority of International Application PCT / EP2020 / 052191 dated January 29, 2020, the disclosures of which are incorporated herein by reference.

[0002] The present invention relates to a lighting unit comprising at least one photoelectron emitter unit.

[0003] The invention also relates to an illumination unit comprising at least one emitter unit emitting radiation via a light exit surface and a polarizing element at least partially adjacent to the light exit surface and changing the polarization and / or the intensity of the radiation emitted by the emitter unit as it passes through the polarizing element.

[0004] The invention also relates to a conversion element for an optoelectronic component, to a radiation source comprising an LED and a conversion element, and to a method for producing a corresponding radiation source.

[0005] The invention also relates to a device, in particular an optoelectronic structural element, in particular a light-emitting diode.

[0006] The present invention relates to an optoelectronic device in which an arrangement with a plurality of light sources for generating light is provided. Such an arrangement may for example be a pixelated array of LEDs, in which one pixel in each case forms one light source.

[0007] As light emitters of photoelectron emitter units, LEDs (LED = Light Emitting Diode) are considered in particular. LEDs are usually Lambertian radiators. The light emitted from the light output surface is not directional. Therefore, the light is usually emitted over the entire solid angle range adjacent to the light output surface.

[0008] In many applications, it is desirable to have a lighting unit with a photoelectron emitter unit with a desired radiation pattern. For very small components, such as components used in the field of high resolution displays or consumer electronics, it is desirable to have a lighting unit that allows directional radiation into a certain solid angle and suppresses radiation into other solid angles as much as possible.

[0009] Technical solutions for beam shaping of the electromagnetic radiation already emerging from the light exit surface of the lighting unit are known from the prior art. For example, optical systems, in particular lenses, can be used to collimate the electromagnetic radiation propagating freely in space. Such lighting units with optical systems downstream of the light exit surface can be quite large. This can be undesirable.

[0010] The invention is based on the problem of providing a lighting unit with an improved radiation pattern, in particular compared to a Lambertian radiator.

[0011] The lighting unit according to the present invention includes at least one photoelectron emitter unit that emits electromagnetic radiation through a light exit surface and a photonic structure that beam shapes the electromagnetic radiation before it emerges through the light exit surface, where the photonic structure shapes the electromagnetic radiation such that it has a constant far field.

[0012] In this way, the photonic structure changes the radiation pattern of the lighting unit from a Lambertian radiator to a defined radiation pattern in the far field. Thus, the expression that the electromagnetic radiation has a specific far field means that the radiation pattern is defined, especially in the far field, and different from the radiation pattern of a Lambertian radiator, where "far field" means an area at least a few centimeters or meters away from the lighting unit, depending on the application.

[0013] The photonic structure may be arranged, in particular in a layer, below the light exit surface and / or between the photoelectron emitter unit and the light exit surface. The photonic structure may thus be integrated into the lighting unit and may be made compact. The photonic structure may be integrated into the light exit surface or an end face of the photonic structure may form the light exit surface.

[0014] The photoelectron emitter unit may comprise at least one LED. The photoelectron emitter unit may comprise a field of LEDs, also called an array.

[0015] The photonic structures may be photonic crystals, quasi-periodic photonic structures or deterministic aperiodic photonic structures. Photonic crystals are understood to be periodic structures that create a photon band structure by periodically varying the refractive index of light. This band structure may have band gaps in certain frequency ranges. These properties can be created by aperiodic, but nevertheless ordered structures. Such structures are in particular quasi-periodic or deterministic aperiodic structures. They may be, for example, helical photonic arrangement structures.

[0016] The photonic structure may be a one-dimensional photonic structure, in particular a one-dimensional photonic crystal, which has a periodic variation of the refractive index along one direction, in particular this direction may extend parallel to the light output surface.

[0017] The one-dimensional structure can form a beam in a first spatial direction. In this case, the photonic effect can be obtained already after a few periods of the photonic structure. For example, the photonic structure can be configured such that the electromagnetic radiation is at least approximately collimated in the first spatial direction. Thus, a collimated beam can be generated at least in the first spatial direction.

[0018] Collimation optics may be arranged downstream of the light exit surface in the radiation direction, the optics being configured to collimate the electromagnetic radiation in a further second spatial direction, perpendicular to the first spatial direction. The first and second directions may be mutually orthogonal directions parallel to the planar light exit surface. In this way, a beam collimated in both directions can be generated along a main radiation direction away from the light exit surface and perpendicular to both the first and second directions.

[0019] According to one configuration of the invention, the photonic structure, in particular the photonic structure formed as a one-dimensional photonic crystal, may be configured such that the main emission direction of the electromagnetic radiation runs at an angle to the normal to the light exit surface, this angle being different from 0 degrees. The main emission direction may therefore run at an incline to the normal to the light exit surface. This allows a beam collimated in at least one direction to be emitted, for example obliquely, from the light exit surface.

[0020] The photonic structure formed as a one-dimensional photonic crystal may be arranged in a layer below, in particular directly below, the light output surface. In this case, the one-dimensional photonic crystal may have a periodically repeating sequence extending in one direction of two materials with different optical refractive indices. The materials may each have a rectangular or parallelogram cross section. In this case, the interface where the materials meet each other may be inclined with respect to the light output surface.

[0021] Such structures can be formed, for example, by etching trenches in a substrate having a light output surface, the trenches extending parallel to each other at an angle to the light output surface. The trenches can be filled with a material having a different optical index of refraction than the substrate material etched away. The angle may depend on the inclination of the trench with respect to the light output surface, and the width of the trenches or the width of the substrate material remaining between the trenches affects the wavelength at which the photonic structure is effective. Typically, the width of the trenches and the width of the substrate material located between the trenches are tailored to the wavelength of the electromagnetic radiation.

[0022] The photonic structure may be a two-dimensional photonic structure, in particular a two-dimensional photonic crystal. An end face of the two-dimensional photonic structure may form the light output surface of the lighting unit, or the two-dimensional photonic structure may be arranged in a layer below the light output surface.

[0023] The two-dimensional structures, in particular two-dimensional photonic crystals, may be configured to influence the electromagnetic radiation such that it forms a defined, in particular discrete, pattern in the far field, so that the illumination unit can be used, for example, in surface topography systems for face recognition.

[0024] As described above, the photonic structure may be disposed in a layer below the light exit surface, or an end face of the photonic structure may form the light exit surface, such that the photonic structure is directly below and encompasses the light exit surface.

[0025] The photonic structure may be formed in a semiconductor layer of the photoelectron emitter unit.

[0026] The photoelectron emitter unit may include a layer having a conversion material, and the photonic structure may be formed in the layer having the conversion material or in a layer between the layer having the conversion material and the light exit surface.

[0027] The optoelectronic emitter unit may comprise at least one optoelectronic laser, for example a VCSEL (vertical-cavity surface-emitting laser). It is also conceivable to arrange several lasers in a field.

[0028] The invention also relates to a surface topography detection system comprising an illumination unit, the illumination unit comprising: The surface topography sensing system further comprises at least one photoelectron emitter unit which emits electromagnetic waves through a light exit surface and a photonic structure which beam shapes the electromagnetic radiation before it emerges through the light exit surface, where the photonic structure shapes the electromagnetic radiation such that it has a constant far field, where the photonic structure is a two-dimensional photonic structure, in particular a two-dimensional photonic crystal, where the two-dimensional photonic structure is configured such that the electromagnetic radiation creates a defined, in particular discrete, pattern in the far field, and the surface topography sensing system further comprises a detection unit, in particular equipped with a camera, formed for detecting the pattern in the far field.

[0029] The surface topography sensing system may include an analysis device configured to determine deviations of the pattern relative to a predetermined reference pattern.

[0030] The analyzer may be configured to determine the shape and / or structure of an object illuminated by the pattern in response to the determined deviations.

[0031] The invention also relates to a scanner for scanning an object, where the scanner comprises an illumination device according to the invention, which can preferably be used for line-by-line detection of the object.

[0032] It can also be considered as a challenge to further design the lighting unit in such a way that it allows for a change in the polarization and / or brightness of the radiation emitted by the at least one emitter, in particular of visible light, in a relatively simple manner. In this case, it can be important that the corresponding lighting unit is designed as space-saving and energy-efficient as possible, where in particular the need to use additional optical elements should be reduced.

[0033] Furthermore, it may be considered desirable to provide a simple, safe and robust lighting unit for emitting polarized electromagnetic radiation as required, which does not cause major problems when combined with other lighting units. Moreover, it is desirable to fabricate the lighting unit on an industrial scale, preferably with already known manufacturing methods. Therefore, technical solutions are desired that are designed in a particularly space-saving manner, allow energy-efficient operation with a high light output, and can be manufactured within an economically rational framework.

[0034] Therefore, a preferred configuration of the lighting device according to the invention relates to an illumination unit comprising at least one emitter unit emitting radiation via a light exit surface and a polarizing element at least partially adjacent to the light exit surface and for changing the polarization and / or the intensity of the radiation emitted by the emitter unit as it passes through the polarizing element, characterized in that the polarizing element has a three-dimensional photonic structure.

[0035] The discussion of a polarizing element changing polarization also includes the creation of polarized radiation from unpolarized radiation. A polarizing element may also cause only a change in the intensity of radiation, possibly depending on the wavelength, without creating or changing the polarization. Thus, the term "polarizing element" should not be interpreted narrowly in the sense that all configurations must provide for changing or creating polarization.

[0036] Based on the configuration according to the invention, an illumination unit is provided in which radiation generated by an emitter, e.g. an LED, reaches the polarizing element directly, thereby realizing a particularly compact unit for providing polarized radiation as required, which unit can also be combined in an advantageous manner with at least one further illumination unit and / or polarizing element, preferably at least one polarizing element having complementary properties.

[0037] An essential advantage of the use of three-dimensional photonic structures, in particular photonic crystals, for polarizing electromagnetic radiation, preferably visible light, is that the arrangement of the photonic structures in the region of the light exit surface of the emitter provides a particularly compact and space-saving solution. By placing a specially designed polarizing element adjacent to the light exit surface, the electromagnetic radiation can be appropriately polarized, while minimizing losses of the electromagnetic radiation whose polarization does not correspond to the polarization direction of the polarizing element. In general, it is conceivable for the photonic structure to be arranged on the light exit surface or for the photonic structure to be suitably formed in the semiconductor layer in which the light exit surface is arranged or on the semiconductor layer adjacent to the light exit surface in the beam direction.

[0038] It is particularly advantageous here that the three-dimensional structure used as polarizing element makes it possible to change the radiation pattern of the lighting unit particularly effectively in terms of its polarization properties, so that different wavelengths can be distinguished by different polarization properties or radiation directions.

[0039] According to one embodiment of the invention, the emitter unit comprises at least one LED, which preferably emits white, red, green or blue light, which is incident on a polarizing element, which polarizes the radiation in the direction of vibration.

[0040] Otherwise, according to one development of the invention, it is provided that the emitter unit, in particular the LED and the polarizing element, are formed from different layers arranged on top of one another in a layer stack. It is also important that the radiation generated in at least one layer of the emitter enters a polarizing element, which is also in the form of a layer, before being emitted from the layer stack into the environment. In an advantageous manner, it is conceivable that the three-dimensional structure used as the polarizing element is arranged on or in the same semiconductor chip as the emitter unit. In the case of using the emitter unit with an LED, it is further conceivable that the photonic structure is applied to the LED chip or is at least part of the LED chip. In such an inventive configuration, a particularly space-saving and energy-efficient lighting unit is available, in which the polarized radiation is generated directly at the chip level, which does not require the arrangement of additional optical elements in the downstream beam path for this purpose. Such a technical solution therefore represents not only a cost-efficient but also a space-saving and energy-efficient technical solution for providing polarized radiation.

[0041] In a further configuration of the invention, the polarizing element has helical and / or rod-shaped structural elements. In this case, the three-dimensional photonic structure is configured in such a way that the light emitted by the emitter unit, in particular an LED, leaves the photonic structure only with a certain polarization. A corresponding three-dimensional photonic structure having helical and / or rod-shaped structural elements in the region of the light exit surface transmits only radiation with a certain polarization direction. Advantageously, the configuration and dimensions of the structure are in each case adapted to the radiation emitted by the emitter unit, in particular an LED. A helical structure results in a circular polarization, while a rod-shaped structure results in a linear polarization of the radiation passing through the structure.

[0042] According to a further development, it is also conceivable that the lighting unit has an LED as an emitter unit, the radiation emitted by the LED impinges on a conversion element with a conversion material as excitation light, and the converted radiation is emitted. In this case, it is generally conceivable that a three-dimensional photonic structure is arranged in the beam path between the LED and the conversion element and / or behind the conversion element, which polarizes the excitation light and / or the converted radiation in a suitable manner. It is also possible to combine the conversion element and the three-dimensional photonic structure in the same layer. This makes it possible to generate directly polarized converted light.

[0043] For example, a three-dimensional photonic structure can be filled with a conversion material. 3+ (Ce is cerium), Eu 2+ (Eu is europium), Mn 4+ The host material may be doped with ions of manganese (Mn) or neodymium. For example, YAG or LuAG can be used. Here, YAG stands for yttrium aluminum garnet. LuAG stands for lutetium aluminum garnet.

[0044] Quantum dots can also be used as conversion materials to fill three-dimensional photonic structures.

[0045] Quantum dots can be very small, for example with dimensions in the range of 10 nm. They are therefore particularly suitable for filling three-dimensional photonic structures. It is generally conceivable to produce the structures by etching away material from the layer in which the structures are formed. The recesses thus formed can then be filled with a conversion material, which for example contains quantum dots. The quantum dots may for example be incorporated in a liquid material filling the recesses. The liquid material may be at least partially evaporated, leaving the quantum dots in the recesses. In this case, part of the liquid material may solidify. The quantum dots may therefore be embedded in a matrix.

[0046] In a further configuration of the invention, the polarizing element comprises at least one three-dimensional photonic crystal. It is also conceivable that the polarizing element comprises at least two two-dimensional photonic crystals arranged in succession along the beam path of the radiation passing through the polarizing element.

[0047] Advantageously, it may be advantageous to use one three-dimensional photonic crystal or at least two two-dimensional photonic crystals arranged in succession in the beam path so that the structure on which the radiation is incident is transparent for radiation of a certain wavelength or several certain wavelengths and / or only in a certain direction. In this way, it is also possible to adjust the desired polarization of the radiation incident on the polarizing element. In this connection, it is conceivable to manufacture the structure directly in the conversion material or to incorporate additional layers of other materials. Here, the properties of the three-dimensional photonic structure are preferably designed in such a way that the transmission conditions are different for various wavelengths. In this way, for example, the converted radiation can pass through the polarizing element unhindered and the excitation light can be redirected. It is likewise conceivable that at least one of the radiation, i.e. the excitation light on the one hand and the converted radiation on the other hand, passes through the polarizing element only with a certain polarization.

[0048] In one configuration of the invention, it may further be provided that the polarizing element has at least two different transmittances depending on the wavelength of the radiation passing through the polarizing element. In this connection, a special development provides that the emitter unit comprises an LED and a conversion element having a conversion material which emits converted radiation when excited by the excitation light emitted by the LED, and that the excitation light incident on the polarizing element is polarized differently and / or absorbed with a different strength when passing through the polarizing element compared to when the converted radiation passes through.

[0049] In this way, the properties of the 3D photonic structure are designed to have different transmission conditions for different wavelengths. In this case, for example, the converted light may pass through the 3D photonic structure unhindered, while the excitation light may be redirected. Similarly, the converted radiation may only exit the 3D photonic structure with a specific polarization.

[0050] It is further assumed that one of the two radiations having different wavelengths is distinguished by the different properties of the polarization and propagation direction of the polarizing element. It is therefore advantageously provided that a combination of LED and conversion element that achieves complete conversion filters out part of the excitation light, except for a relatively small portion of radiation having a specific wavelength, so that a thinner layer of conversion material can be used.

[0051] The advantages of the invention can be used in a particularly advantageous manner if an emitter unit with an LED is provided and the three-dimensional structure of the polarizing element is applied directly on the LED chip, preferably on a semiconductor layer of the LED, which mediates the generated radiation reaching the light exit surface. According to this configuration, the three-dimensional photonic structure is arranged directly on or in the LED chip. Such a technical solution allows an increased resolution of the image generation on the basis of polarized radiation emission and allows the components for beam generation to be configured relatively compact. This can be achieved, for example, in that radiation emitted by several components or lighting units with complementary properties is imaged via a common optical system. Optical systems suitable for this are disclosed in the present application. The lighting units thus formed can therefore be used in particular in the field of household appliances.

[0052] In other respects, the present invention relates to a method for manufacturing an illumination unit comprising at least one emitter unit emitting radiation via a light exit surface and a polarizing element at least partially adjacent to the light exit surface and changing the polarization and / or brightness of the radiation emitted by the emitter unit as it passes through the polarizing element.

[0053] According to the invention, this method could be developed by providing a chip equipped with an LED as an emitter unit and applying a three-dimensional photonic structure as a polarizing element to its light exit surface, for example by two-photon lithography or oblique deposition, and / or introducing a photonic structure into a semiconductor layer of the LED adjacent to the light exit surface.

[0054] According to a special development of the method, the three-dimensional structure can change its dimensions depending on the wavelength of the radiation emitted by the LED.

[0055] Advantageously, a lighting unit configured according to at least one embodiment of the invention can be used in a device for generating three-dimensional images, in particular for displaying on a display, monitor or screen.

[0056] Particularly advantageously, the lighting unit constructed according to the invention can further be used for computer-aided generation of three-dimensional images, where it is advantageous that the lighting unit according to the invention with a three-dimensional photonic structure as a polarizing element changes the radiation pattern of the LED with respect to the polarization properties, so that discrimination of different wavelengths can be achieved due to different, wavelength-specific polarization properties or radiation directions.

[0057] A major advantage here is that polarized radiation, in particular polarized light, can be generated directly on the substrate with the emitter unit, in particular at the level of the LED chip, or the selectivity can be increased by complete conversion. By emitting suitably polarized radiation, the resolution of the three-dimensional image can be increased while at the same time the structural elements or lighting units required for image generation can be reduced. This can be advantageously achieved by imaging the light of several structural elements with complementary properties onto a display or screen via a common optical system. Particularly in the field of household appliances, a combination of complementary polarizing elements can be used to generate three-dimensional images in a particularly advantageous manner.

[0058] It may also be desirable to further design not only conversion elements for optoelectronic components, but also radiation sources with such conversion elements in such a way that the arrangement of the individual components is particularly space-saving and thus the structural form of the radiation source consisting of an emitter for emitting excitation light and a conversion element can be particularly small. Here, it may be of great importance to selectively radiate the radiation emitted by the radiation source into a certain spatial region and to reliably prevent radiation into other regions in a relatively simple manner. Furthermore, it may be desirable to have a technical solution that is characterized by a high energy efficiency and thus a relatively high light output compared to known technical solutions.

[0059] Furthermore, it may be considered desirable for a radiation source consisting of an emitter for emitting excitation light and a conversion element for generating converted radiation to be realizable in a simple and cost-effective manner in terms of manufacturing technology, in particular by known manufacturing methods. In this respect, it may be considered desirable to specify a method for manufacturing the radiation source.

[0060] The invention also relates to a conversion element for an optoelectronic component, which comprises at least one layer with a conversion material which emits converted radiation in the emission region when excited by incident excitation light. According to the invention, the conversion element is characterized in that the layer comprises, at least in some regions, a structure in which the conversion material is at least partially arranged, which structure is configured in such a way that the radiation is emitted as a directed beam bundle towards the emission region. An essential feature of the invention is the provision of a layer patterned in a suitable manner, in or on which a conversion material is applied which emits converted radiation when excited by excitation or pump light. By combining the conversion material on the one hand and the components of the patterned layer for selective beam steering and / or shaping on the other hand, an element is created which can selectively emit radiation in the emission region of the radiation source in a particularly space-saving manner and limited to a desired spatial region. In this connection, it is conceivable that the excitation light as well as the converted radiation emitted by the conversion element are directed in a suitable manner so that radiation is emitted only in a specific direction, while emitting such radiation in other directions and / or regions is excluded.

[0061] It is generally conceivable that at least some regions of the structure, also referred to herein as photonic structure, are coated with a suitable conversion material and / or at least individual regions, for example recesses of the structure, are filled with a suitable conversion material. In this case, the structure is configured such that the emitted converted radiation is emitted as a beam bundle in the desired direction of the emission area. In this connection, it is also conceivable to configure the structure such that there are different areas from which beam bundles of radiation are emitted. In this way, conversion elements can be provided which are used in optoelectronic components and adjust the radiation pattern of the optoelectronic component as required. In particular, by suitable patterning of the layers, it is possible to provide conversion elements and change the emission profile of the optoelectronic component in which the conversion element is used such that no further radiation is emitted according to Lambert's law and a suitably unidirectionally directed beam or beam bundle is generated.

[0062] The conversion material is Ce 3+ (Ce is cerium), Eu 2+ (Eu is europium), Mn 4+ The host material may be doped with ions of manganese (Mn) or neodymium. For example, YAG or LuAG can be used. Here, YAG stands for yttrium aluminum garnet. LuAG stands for lutetium aluminum garnet.

[0063] As conversion material, quantum dots also come into consideration. They are very small, for example in the range of 10 nm. They are therefore particularly suitable for filling the aforementioned recesses of the photonic structure. It is generally conceivable to produce the photonic structure by etching away the material of the recess from the layer in which the photonic structure is formed. The recess can then be filled with a conversion material, which comprises, for example, quantum dots. The quantum dots may for example be incorporated in a liquid material filling the recess. The liquid material may be at least partially evaporated, leaving the quantum dots in the recess. In this case, part of the liquid material may solidify. The quantum dots may therefore be embedded in a matrix.

[0064] Photonic structures do not usually change the spectral properties of quantum dots. However, quantum dots have a narrow emission spectrum. Photonic structures can be adapted to this narrow emission spectrum, thereby improving the directional selectivity they provide. Thus, the radiation pattern of quantum dots as converters can be very efficiently influenced by photonic structures.

[0065] In one embodiment of the present invention, it is provided that the structure has structural elements arranged quasi-periodically or deterministically aperiodically. Such a regular structure offers the advantage that the optical properties of the conversion element with the corresponding patterned layer can be adjusted particularly reliably, safely and reproducibly. In this case, the structure is advantageously configured such that radiation of a certain wavelength or a certain wavelength range can be transmitted through the layer, particularly in a predefined direction, while this radiation cannot be transmitted through the layer in other directions. Alternatively or additionally, the patterned layer can be configured such that it is transparent or non-transparent to radiation of a certain wavelength, at least in a wide range.

[0066] According to a development of the invention, it is provided that the layer comprises at least one photonic crystal. By using a suitable photonic crystal, the propagation of radiation of a selected wavelength or wavelength range can be specifically blocked, at least in a specific direction, so that a beam or beam bundle of converted radiation can be emitted, if necessary, in a directed manner, in a spatial region or emission region provided for this purpose. Deterministic non-periodic structures and quasi-periodic structures can have the same functions as photonic crystals. However, slightly different properties may exist in the far field. Thus, when photonic crystals are mentioned in this specification, this also applies to deterministic non-periodic structures and / or quasi-periodic structures.

[0067] Photonic crystals are understood to mean periodic structures that create a photon band structure by periodically varying the refractive index of light. This band structure can have a band gap in a certain frequency range. Alternatively, this property can also be created in aperiodic, but ordered structures. Such structures are in particular quasi-periodic or deterministic aperiodic photonic structures. They can be arranged, for example, in a spiral.

[0068] Furthermore, it is advantageous for the structure to have at least one recess in which the conversion material is arranged. Advantageously, in this connection, it is proposed that the structure has a number of protrusions and recesses, the recesses being at least partially filled with a suitable conversion material. In this way, the conversion element can be realized relatively easily by combining the structure provided by the invention with a conversion material so that the converted radiation is only emitted in a particularly limited emission area and thus is emitted in a particularly targeted manner. In principle, in this connection, it is conceivable to configure the conversion element in such a way that the excitation light is appropriately directed by the structure to the area of ​​the conversion material provided for this purpose and / or the converted radiation enters the structure and is thus emitted as a suitably emitted beam bundle in the desired emission area.

[0069] Advantageously, the layer with the structure is configured such that the layer has at least one optical band gap. In this context, a band gap is understood to be a region of the layer with solid material that is between the valence band and the conduction band. This band gap makes the solid used in the layer and thus the conversion element with the layer transparent to radiation in a certain frequency range. By suitable adjustment of the band gap and / or selection of the solid material, the optical properties of the conversion element can be appropriately adjusted. In particular, it is possible to configure the layer such that only a part of the incident radiation passes through the layer and is emitted into the emission region. Advantageously, the structure of the layer has an average thickness of at least 500 nm. In this case, advantageously, a photonic structure, in particular a photonic crystal, a quasi-periodic structure or a deterministic aperiodic structure, with a layer thickness of at least 500 nm is selected, whereby the optical band gap is created.

[0070] According to one further development of the invention, it is provided that the layer with the structures is designed in such a way that the directional beam bundle is emitted perpendicular to the plane in which the layer is arranged, whereby it is provided that the radiation emitted into the emission region is arranged perpendicular to the layer plane, while the radiation components emitted into other spatial regions are reliably suppressed.

[0071] Furthermore, it is an advantageous development of the invention if an optical filter element is arranged on at least one side of the layer. Advantageously, such a filter element is configured as a filter layer that is applied on the side of the patterned layer with conversion material. By using such a filter element or filter layer, it is possible that only a certain part of the radiation is incident on the layer with conversion material or that only a certain part of the converted radiation emitted by the patterned layer with conversion material is emitted into a desired spatial region.

[0072] Thus, advantageously, the filter element, in particular the filter layer, is configured in such a way that only that part of the radiation which is required as excitation light or which should be emitted appropriately in the emission region can pass through the filter element or filter layer.

[0073] Furthermore, the invention relates to a radiation source with an LED, which irradiates an excitation light onto a conversion element formed according to at least one of the previously described configuration examples of a conversion element constructed according to the invention. The conversion element itself has at least one layer with a conversion material, which, when excited by the excitation light emitted by the LED, emits converted radiation into a radiation area. In this connection, it is conceivable to combine an LED with a conversion element in such a way that all of the excitation light emitted by the LED is converted into converted radiation or only a part of the excitation light emitted by the LED is converted into converted radiation. It is also important that the radiation emitted by the radiation source is directed only into a desired spatial area. In this way, the radiation source generates a directional beam or a directional beam bundle that is emitted in an appropriately selected direction or into an appropriately selected radiation area.

[0074] According to one development of the invention, the patterning layer with the conversion material is part of the semiconductor substrate of the LED. In this case, the structure can advantageously be formed in the semiconductor substrate of the LED. In this connection, it is further advantageously conceivable to produce the structure by suitable etching of the LED semiconductor substrate and then to at least partially coat the structure with the conversion material and / or fill the etched recesses of the structure with the conversion material.

[0075] Furthermore, it is advantageously provided that the structure with the conversion material is configured such that the converted radiation is emitted to the emission area perpendicular to the plane in which the semiconductor substrate is arranged. In this case, the structure is configured such that the converted radiation is emitted to the emission area only perpendicular to the surface of the LED chip due to the band gap effect. This technical solution results in a high directivity of the converted radiation emitted by the conversion element. In this connection, it is conceivable that the structure, in particular the photonic structure, for example in the form of a photonic crystal, is arranged only in the topmost layer of the semiconductor material of the LED or at least partially also in the active zone. In order to ensure the generation of the optical band gap, it is also advantageous that the layer thickness of the structure is at least 500 nm.

[0076] In a special configuration, it is provided that at least one filter layer is arranged on at least one side of the patterning layer. In this connection, it is also conceivable that the excitation light generated by the LED is suppressed in a certain wavelength range by using the filter layer. In this way, the generation of directional radiation in the patterning layer of the conversion element can make systems based on the complete conversion of the excitation light, especially those with étendue limitations, significantly more efficient than known technical solutions.

[0077] According to a development of the invention, the radiation source is configured to emit visible white light or visible converted light having the colours characteristic of the RGB colour space, namely red, green and blue.

[0078] According to a further configuration, the radiation source comprises an LED or several LEDs which are arranged next to each other in an array and can be individually driven and controlled.

[0079] According to a further configuration, the radiation source may be, for example, a pixelated array in which the individual pixels of a larger component are individually turned on and off.

[0080] It is advantageous to use photonic structures as described herein in combination with very small LEDs, such as the LEDs mentioned above, or pixelated arrays, since classical optical components such as lenses can only be used to a very limited extent at small sizes. Furthermore, with photonic structures, the contrast between adjacent pixels can be improved, since they provide directionality.

[0081] According to further configurations, it is also possible to design the radiation source as a chip-sized package, in particular in components without a suitable housing, where optical elements of the type described here are particularly advantageous, since classical lenses cannot be fitted well in very compact components or would make the components too large.

[0082] Furthermore, the invention also relates to a method for manufacturing a radiation source having at least one of the above-mentioned specific characteristics, characterized in that the structure is formed by at least one etching step in a semiconductor substrate of the LED, whereby it is advantageous if the structure, in particular selected recesses therein, are at least partially filled with a conversion material.

[0083] There may be a need for structures that can provide extraction, particularly light extraction, from a semiconductor body.

[0084] According to a first aspect, a method for producing a device, in particular an electronic component, in particular an optoelectronic component, in particular a light-emitting diode, is proposed, in which a surface region of a semiconductor body providing the device is patterned and the patterned surface region is planarized to produce an extraction structure, in particular an optical extraction structure, in order to obtain a planarized surface of the surface region. In particular, planarization means forming a planarity, which can also be called flatness.

[0085] According to a second aspect, a device, in particular an electronic component, in particular an optoelectronic component, in particular a light-emitting diode, is proposed, in which an extraction structure is created in a surface region of a semiconductor body providing the device by patterning the surface region and planarizing the patterned surface region to obtain a planarized surface of the surface region.

[0086] The proposed extraction structure can be used to emit light from a surface in a direction perpendicular to the surface.

[0087] According to the proposed arrangement, patterning of a surface area of ​​a semiconductor body, which may also be called a die, can be performed by generating a random topology in the surface area.

[0088] According to a further proposed configuration, the random topology can be generated by directly roughening the surface of the surface region of the semiconductor body which comprises the first material.

[0089] According to a further proposed configuration, the random topology can be created by applying a transparent second material, in particular Nb2O5, having a high refractive index, in particular a refractive index greater than 2, to the surface region and roughening this second material, which can be provided as a layer on the surface region.

[0090] According to a further proposed configuration, the patterning of the surface region of the semiconductor body can be effected by creating an ordered topology in the surface region.

[0091] According to a further proposed configuration, an ordered topology can be generated by applying a transparent second material, in particular Nb2O5, with a high refractive index, in particular a refractive index greater than 2, and patterning periodic photonic crystals or aperiodic photonic structures, in particular quasi-periodic or deterministic aperiodic photonic structures, in the second material. The second material can be provided as a layer.

[0092] Photonic crystals are understood to mean periodic structures that create a photon band structure by periodically varying the refractive index of light. This band structure can have a band gap in a certain frequency range. Alternatively, this property can also be created in aperiodic, but ordered structures. Such structures are in particular quasi-periodic or deterministic aperiodic photonic structures. They can be arranged, for example, in a spiral.

[0093] According to a further proposed configuration, the planarization of the surface region of the semiconductor body can be achieved by applying a transparent third material having a low refractive index, in particular below 1.5, in particular SiO2, to the surface region. The third material can be provided as a layer.

[0094] According to a further proposed configuration, TEOS (tetraethyl orthosilicate) can be used to apply SiO2 as a transparent third material with a low refractive index.

[0095] According to a further proposed configuration, the thinning of the third material with a low refractive index can be performed until at the surface the highest peaks of the first material of the semiconductor body or the highest peaks of the second material with a high refractive index are flat and / or smooth.

[0096] According to a further proposed configuration, the thinning can be performed by chemical mechanical polishing (CMP).

[0097] According to a further proposed configuration, the transfer of the device can be performed using stamping techniques.

[0098] According to a further proposed configuration, the planarized surface may be flat and / or smooth and have a roughness in the range of less than 20 nanometers, in particular less than 1 nanometer, as average roughness value.

[0099] According to a further proposed configuration, the extraction structure can comprise a transparent third material with a low refractive index, in particular SiO2, on the semiconductor roughened first material of the structural element.

[0100] According to a further proposed configuration, the extraction structure can have a transparent third material with a low refractive index, in particular SiO2, on a roughened transparent second material with a high refractive index, in particular Nb2O5, where the second material may be provided on a semiconductor first material of the structural element.

[0101] According to a further proposed configuration, the extraction structure can comprise a transparent third material with a low refractive index, in particular SiO2, on a transparent second material with a high refractive index, where the second material is provided on the semiconductor first material of the structural element and can comprise a periodic photonic crystal or an aperiodic photonic structure, in particular a quasi-periodic or deterministic aperiodic photonic structure.

[0102] It may also be considered desirable to provide improved optoelectronic devices that emit light at least substantially perpendicular to the light emitting surface.

[0103] The present invention also relates to an optoelectronic device including an arrangement having a plurality of light sources for generating light to be emitted from a light emission surface of the optoelectronic device, and further including at least one photonic structure disposed between the light emission surface and the plurality of light sources.

[0104] At least one photonic structure (in particular a photonic crystal or a pillar structure, also referred to herein as a column structure) allows for beam shaping of the emitted light before it leaves the device through the light exit surface.

[0105] In particular, the photonic structure may be configured to beam shape the light generated by the light source, in particular the photonic structure may be formed such that the light exits at least substantially perpendicularly from the light exit surface, in this way improving the directionality of the emitted light.

[0106] Photonic crystals are known per se. They are in particular periodic structures of the optical refractive index that occur or are created in transparent solids. In particular, so-called two-dimensional photonic crystals are concerned here, in which the optical refractive index varies periodically in two mutually perpendicular spatial directions, in particular in two mutually perpendicular spatial directions that run parallel to the light exit surface.

[0107] According to one embodiment of the invention, the arrangement is an array having a plurality of pixels arranged in a layer as light sources, the photonic crystal being arranged or formed in a layer, whereby the photonic crystal may be arranged directly in the layer in which the pixels of the array are arranged, or may be arranged in a layer above the light sources, whereby the photonic crystal is still located between the light sources and the light exit surface.

[0108] In particular, this layer may comprise a semiconductor material, and the photonic crystal may be patterned in the semiconductor material. As examples of semiconductor materials, the GaN or AlInGaP material systems are considered, where GaN stands for gallium nitride, and where AlInGaP stands for aluminum indium gallium phosphide. Examples of other possible material systems include AlN (aluminum nitride) and InGaAs (indium gallium arsenide).

[0109] A photonic crystal can be realized by forming a periodic change in the optical refractive index in a semiconductor material, and for this purpose, a high refractive index material such as Nb2O5 (niobium (V) oxide) can be used and appropriately introduced into the semiconductor material. In this case, the photonic crystal is preferably formed as a two-dimensional photonic crystal having a periodic change in the optical refractive index in two spatial directions perpendicular to each other in a plane extending parallel to the light emission direction.

[0110] According to one configuration of the invention, the arrangement is an array with a plurality of pixels arranged in a first layer as light sources, and a photonic crystal arranged in a further second layer, the second layer being located between the first layer and the light exit surface. The photonic crystal can thus be arranged or housed in an additional second layer above the layer with the plurality of pixels. The photonic crystal can again be formed, for example, as a two-dimensional photonic crystal. The photonic crystal can be realized by holes or recesses formed in a high refractive index material, for example Nb2O5. In this way, the photonic crystal can be or may be formed by forming corresponding patternings in the high refractive index material. The photonic structure can be filled with a low refractive index material, for example silicon dioxide.

[0111] According to one aspect of the invention, the arrangement comprises a number of LEDs as light sources, the LEDs being arranged in a first layer and the photonic crystal being arranged or formed in a further second layer, the second layer being located between the first layer and the light exit surface. In particular in combination with LEDs arranged in an array, the photonic crystal may be provided in a further second layer above the first layer with the LEDs. This is preferably formed as a two-dimensional photonic crystal, realised in the form of a periodic change in the optical refractive index in two spatial directions parallel to the light exit surface and running perpendicular to each other. As an example of a high refractive index material, Nb2O5 may again be mentioned, and the photonic crystal may be patterned by providing holes or recesses in the high refractive index material. The photonic structure may be filled with a low refractive index material, for example silicon dioxide.

[0112] A distinction can be made between horizontal and vertical LEDs. In the case of horizontal LEDs, the electrical terminals are on the back of the LED, not facing the light-emitting surface. In contrast, vertical LEDs have one electrical terminal on the front and one on the back of the LED, where the front faces towards the light-emitting surface.

[0113] In pixelated arrays with bipolar electrical contacts on the backside, the entire array surface can be patterned, for example in the form of a photonic crystal, in particular without omitting mesa trenches or contact surfaces. A similar arrangement can be achieved with lateral light-emitting diodes arranged below the carrier substrate.

[0114] According to one aspect of the invention, in an array or arrangement of lateral light emitting diodes for electrically contacting light sources, the poles may be electrically connected to each other by a contact layer that reflects the generated light and is located below the photonic structure and the light source as viewed from the light output surface on the top surface, and the contact layer may have at least two electrically isolated regions to avoid short circuits between the poles.

[0115] According to another configuration of the invention, in an arrangement of a vertical light-emitting diode for electrical contact with a light source, the first pole not facing the light output surface, in particular the positive pole, may be electrically connected to a contact layer that reflects the generated light, the contact layer being located below the photonic structure and the light source as viewed from the light output surface on the top.

[0116] According to one embodiment of the invention, the second pole, in each case the other, in particular the negative, facing the light exit surface, may be electrically connected by a layer of an electrically conductive and optically transparent material, in particular ITO, and a filler material may be arranged between the layer and the reflective contact layer.

[0117] According to one configuration of the invention, each of the light sources may have a recombination zone, and the photonic crystal may be arranged in the vicinity of the recombination zone such that the photonic crystal changes the optical density of states present in the region of the recombination zone, in particular such that a band gap is generated for at least one optical mode whose propagation direction is parallel and / or at a small angle to the light output surface. In order to generate an optical band gap in the region of the recombination zone, it is advantageous for the photonic crystal to be very close to the recombination zone. Furthermore, in order to generate a band gap, it is advantageous for the height of the photonic crystal to be large, in particular 300 nm or more, as viewed perpendicularly to the light output surface. The photonic crystal can thus suppress the emission of light whose propagation direction is parallel and / or at a small angle to the light output surface, so that the light already emitted in the light generating region can be made directional. Light is thereby generated only in a limited emission cone perpendicular to the light output surface. Here, the opening angle of the emission cone depends on the photonic crystal and can be a small value, for example up to 20°, up to 15°, up to 10° or up to 5°.

[0118] The photonic crystal may be arranged on a plane extending parallel to the light exit surface, regardless of the position of the light spot.

[0119] Photonic crystals can be produced using known lithography techniques, such as nanoimprint lithography or immersion EUV stepper (EUV stands for extreme ultraviolet).

[0120] The photonic structure may include a plurality of pillar structures extending at least partially between the light output surface and a plurality of light sources, each pillar being assigned to a light source and aligned so as to be coplanar with the light output surface when viewed in a direction perpendicular to the light output surface.

[0121] A pillar can also be called a column. A pillar or column preferably has a longitudinal axis extending perpendicular to the light exit surface. If a pillar and its assigned light source are aligned in the same plane, this means in particular that the longitudinal extension axis of the pillar intersects the center point of the light source.

[0122] When viewed perpendicular to the longitudinal axis, the pillars may have a circular, square or polygonal cross-section. Preferably, the pillars have a height to diameter aspect ratio of at least 3:1, where the height is measured in the direction of the longitudinal axis of the pillar.

[0123] In particular, the pillars are made of a high refractive index material, such as Nb2O5. Because of the higher refractive index compared to the surrounding materials, the amount of light emitted parallel to the longitudinal axis of the pillars can be increased compared to other spatial directions. The pillars act as waveguides. This allows light along the longitudinal axis of the pillars to be extracted more efficiently than light along other propagation directions. This improves the directivity of the light in the direction of the longitudinal axis. Furthermore, since the longitudinal axis of the light preferably extends perpendicular to the light exit surface, the light extraction perpendicular to the light exit surface can be improved.

[0124] The arrangement may be an array having a number of pixels arranged in a first layer as light sources, and the pillars may be arranged in a further second layer, the second layer being between the first layer and the light exit surface. Thus, the pillars may be arranged on the surface of the pixelated array. In this case, the pillar or column structure may be formed independently from the high refractive index material. Furthermore, the gaps between the pillars may be filled with a filling material, such as silicon dioxide, having a low refractive index.

[0125] The arrangement structure may have a number of LEDs as light sources arranged in a first layer, and the pillars may be arranged or formed in a further second layer, where the second layer is between the first layer and the light exit surface.

[0126] The arrangement may be an array having a plurality of pixels arranged in a first layer as light sources, the pillars being arranged in the first layer as well. In particular, the pillars may be arranged in the first layer such that at least a respective portion of the pillar is closer to the light output surface than the light source assigned to the pillar. The pillars may thereby function as optical waveguides between the light source and the light output surface. The pillars may be formed from a semiconductor material of the array arranged in the first layer, the semiconductor material having a high refractive index. In particular, the semiconductor material of the first layer may be etched away so as to leave the pillars. The gaps between the pillars may again be filled with a low refractive index material.

[0127] The arrangement may be an array having a number of pixels in the form of pixels, in particular LEDs, as light sources, where the pixels are formed in pillars. In this way, an array can be created in which the individual pixels are in the form of pillars. In this respect, each pillar is advantageously an LED and serves as an individual pixel. The length of the pillar, relative to the longitudinal axis of the pillar, can correspond to half the wavelength of the emitted light, and the recombination zone of the LEDs formed by the pillar is preferably located in the center of the pillar. The recombination zone is therefore located at a local maximum of the density of photonic states. This allows a significant increase in the amount of light emitted parallel to the longitudinal direction of the pillar. Due to the waveguide effect, light with a propagation direction parallel to the longitudinal axis is extracted more efficiently than light with other propagation directions.

[0128] The aspect ratio of the pillar height to diameter is advantageously 3:1. At typical emission wavelengths, the pillar height is about 100 nm and the diameter is 30 nm. It is also possible to scale up the height and / or diameter to a larger value, which is easier to manufacture. Between the pillars with the light source, a material with a lower refractive index than the semiconductor material of the pillar, such as silicon dioxide, may be filled.

[0129] In the case of pillars with a light source, a p-contact can be provided on the bottom surface of the pillar, not facing the light exit surface. An n-contact can be provided, for example, on the top surface of the pillar at half the height of the pillar. The n-contact can be provided on a transparent conductive material, in particular as an intermediate layer of a filling material or as a top layer on the pillar. ITO (indium tin oxide) is for example a possible material for the n-contact layer. It is also possible to reverse the arrangement of the n-contact and the p-contact.

[0130] In particular, in the case of an arrangement of light-emitting diodes for electrical contact connection shaped as a pillar or column, in particular vertical, one first pole, in particular the positive pole, in each case may be electrically connected to a reflective contact layer which may be formed on and / or along a first longitudinal end of the light-emitting diode.

[0131] The other, in each case in particular the negative, second pole may be electrically connected to a further layer of electrically conductive and optically transparent material, in particular ITO, which may be arranged in the centre of the pillar or column as an intermediate layer or on and / or along a second longitudinal end of the pillar, which second longitudinal end is opposite the first longitudinal end.

[0132] According to a further aspect, an optoelectronic device is proposed for generating light emission perpendicular to the light emitting surface, in particular from a planar, pixelated array or arrangement of light emitting diodes, in which optically acting structures, in particular nanostructures such as photonic crystals or pillar structures, are patterned along the entire light emitting surface in order to emit light in the perpendicular direction.

[0133] According to a further aspect, a method for producing an optoelectronic device for generating light emission perpendicular to the light emitting surface, in particular from a planar, pixelated array or arrangement of light emitting diodes, is proposed, in which optically active structures are patterned along the entire light emitting surface in order to emit light in the perpendicular direction.

[0134] In particular, a planar array means in particular an array that is planar. Furthermore, the surface of the array or field is advantageously smooth. In particular, a pixelated array is a monolithic pixelated array.

[0135] All the materials mentioned, in particular the photonic crystals, pillars or filling materials, preferably have a low absorption coefficient, in particular the absorption coefficient being a measure of the reduction in intensity of electromagnetic radiation as it passes through a given material.

[0136] The configuration variants of the present invention will be described in more detail below with reference to the accompanying drawings. [Brief description of the drawings]

[0137] [Figure 1] FIG. 2 is a perspective view of a first variant of the lighting unit according to the invention; [Diagram 2] FIG. 4 is a cross-sectional view of a second variant of the lighting unit according to the present invention. [Diagram 3] FIG. 3 is a diagram showing an arrangement structure of a plurality of lighting units in FIG. 2. [Figure 4] FIG. 11 is a perspective view of a fourth variant of the lighting unit according to the present invention. [Diagram 5] 5 shows a block diagram of a surface topography sensing system including the illumination unit of FIG. 4. [Figure 6] FIG. 1 shows an illumination unit including an emitter unit having a light exit surface to which a polarizing element of a three-dimensional photonic structure is applied. [Figure 7] FIG. 1 illustrates a three-dimensional photonic structure having multiple helical structural elements. [Figure 8] FIG. 1 shows an illumination unit comprising an emitter unit having a light exit surface provided with a polarizing element having a three-dimensional photonic structure with wavelength-selective properties. [Figure 9] FIG. 1 shows an illumination unit having an emitter unit and a three-dimensional photonic structure filled with a conversion material. [Figure 10] 1A and 1B show top and cross-sectional views of a radiation source comprising an LED and a conversion element formed of a patterned layer filled with conversion material located only on the topmost layer of the LED semiconductor material; [Figure 11] FIG. 2 shows a cross-sectional view of a radiation source having an LED, a conversion element formed of a patterning layer filled with conversion material arranged only on the topmost layer of the LED semiconductor material, and a filter layer applied to the topmost layer of the LED semiconductor material; [Figure 12]1A and 1B show top and cross-sectional views of a radiation source comprising an LED and a conversion element formed of a patterned layer filled with a conversion material that extends to the active zone of the LED semiconductor material. [Figure 13] FIG. 2 shows a cross-sectional view of a radiation source having an LED, a conversion element formed of a patterned layer filled with conversion material extending to the active zone of the LED semiconductor material, and a filter layer applied to the top layer of the LED semiconductor material. [Figure 14] FIG. 1 is a diagram showing an example of the configuration of a proposed device. [Figure 15] FIG. 13 is a diagram showing a further example configuration of the proposed device. [Figure 16] FIG. 13 is a diagram showing a further example configuration of the proposed device. [Figure 17] FIG. 1 is a diagram showing an example of a configuration of a proposed method. [Figure 18a] FIG. 2 is a top view of the first proposed device. [Figure 18b] FIG. 2 is a cross-sectional view of a first proposed device. [Figure 19a] FIG. 13 is a top view of the second proposed device. [Figure 19b] FIG. 2 is a cross-sectional view of a second proposed device. [Figure 20a] FIG. 13 is a top view of the third proposed device. [Figure 20b] FIG. 13 is a cross-sectional view of a third proposed device. [Figure 21a] FIG. 13 is a top view of the fourth proposed device. [Figure 21b] FIG. 11 is a cross-sectional view of the fourth proposed device. [Figure 22a] FIG. 13 is a top view of the fifth proposed device. [Figure 22b] FIG. 13 is a cross-sectional view of the fifth proposed device. [Figure 23a] FIG. 13 is a top view of the sixth proposed device. [Figure 23b] FIG. 13 is a cross-sectional view of the sixth proposed device. [Figure 24a] FIG. 13 is a top view of the seventh proposed device. [Figure 24b] FIG. 13 is a cross-sectional view of the seventh proposed device. [Figure 25a] FIG. 13 is a top view of the eighth proposed device. [Figure 25b] FIG. 13 is a cross-sectional view of the eighth proposed device. [Figure 26a] FIG. 13 is a top view of the ninth proposed device. [Figure 26b] FIG. 13 is a cross-sectional view of the ninth proposed device. [Figure 27] 4 shows a cross-sectional view of a further variant of the device according to the invention.

[0138] The illumination unit 11 shown in Fig. 1 comprises at least one photoelectron emitter unit 13, which is formed to emit electromagnetic radiation 19, e.g. visible or infrared light of different wavelengths, via a light exit surface 15. Here, a photonic structure 17 is provided for beam shaping the electromagnetic radiation before it is emitted via the light exit surface 15. The photonic structure 17 shapes the electromagnetic radiation 19 such that it has a defined pattern 23 in the far field 21.

[0139] In particular, the photonic structure 17 of the lighting unit 11 of Fig. 1 is a one-dimensional photonic crystal 25. This structure extends to the light exit surface 15 in the illustrated variant. The end faces of the photonic crystal 25 thus form the light exit surface 15. The one-dimensional photonic crystal 25 has a periodic variation of the optical refractive index along the first direction R1.

[0140] The crystal 25 or the periodic variation is set to beam-shape the electromagnetic radiation emitted by a light source (not shown) of the emitter unit. In particular, the propagation of light along the first direction R1 is blocked. As a result, the emitted radiation 19 in the far field 21 spreads only slightly along the first direction R1. It is thus characteristic that the electromagnetic radiation 19 in the far field 21 forms a narrow strip 27. The electromagnetic radiation 19 is therefore collimated with respect to the first direction R1.

[0141] The light source is in particular an LED, which is typically a Lambertian radiator. Using the photonic structure 17 and the resulting beam shaping, a directional collimated electromagnetic radiation 19 can be generated.

[0142] As FIG. 1 shows diagrammatically, the emitted electromagnetic radiation 19 leaves the emitter unit 13 in the form of a light cone that is substantially fanned out along the second direction R2. The central axis of the light cone extends along a main radiation direction H that runs perpendicular to the light exit surface 15. Not shown are any collimation optics downstream of the light exit surface 15, as seen in the main radiation direction H. By means of these optics, the electromagnetic radiation 19 can be collimated in a second spatial direction R2 that runs perpendicular to the first spatial direction R1. In this way, the electromagnetic radiation 19 can be collimated in the far field 21 with respect to the two directions R1, R2. This results in a spot.

[0143] The illumination device 11 according to Fig. 1 is particularly suitable for use in optical scanners, where the illumination device 11 can in particular be used for line-scanning applications with a strip-like light image in the far field 21.

[0144] In the lighting device 11 shown in Fig. 2, a one-dimensional photonic crystal 25 is formed on top of the emitter unit 13. An end face of the crystal 25 forms the light exit surface 15 for electromagnetic radiation generated by an optoelectronic light source, not shown, for example an LED, passing through the photonic crystal 25 and emitted via the light exit surface 15.

[0145] In contrast to the variant according to FIG. 1, in the lighting unit of FIG. 2 the main emission direction H of the electromagnetic radiation 19 extends at an angle α with respect to the normal N of the light output surface 15. Here, the angle α is not 0 degrees. For example, the angle α can be in the range of 30 degrees to 60 degrees. This is achieved in that the one-dimensional photonic crystal 25 has a periodically repeated sequence of two materials 31, 33 with different optical refractive indices, extending in a first direction R1. The materials 31, 33 have a parallelogram-shaped cross section, as shown diagrammatically in FIG. 2, and the interface at which the materials 31, 33 abut each other is inclined with respect to the light output surface 15 without being orthogonal.

[0146] Such a structure can be formed, for example, by etching parallel trenches 29 in a substrate 31 having a light output surface 15 at an angle to the light output surface 15. The trenches 29 can be filled with a material 33 having a different optical index of refraction than the etched away substrate material 33. The angle α here may depend on the inclination of the trenches 29 with respect to the light output surface 15. The width of the trenches 29 and the width of the respective substrate material 31 remaining between the two trenches 29 influence the wavelengths at which the photonic crystal 25 can be effective. Typically, the width of the trenches 29 and the width of the substrate material 33 located between the two trenches, and thus the periodicity of the photonic crystal structure 25, are adapted to the wavelength of the electromagnetic radiation provided by the light source or by a conversion material arranged between the light source and the photonic crystal.

[0147] By means of the one-dimensional photonic crystal 25, the lighting unit 11 according to Fig. 2 can also generate light strips 27 in the far field 21, as explained with reference to Fig. 1. In contrast to the variant of Fig. 1, the main radiation direction H in the variant of Fig. 2 is inclined by an angle α to the normal N. Collimation optics arranged downstream allow the strips 27 to be point-like or circular structures in the far field 21.

[0148] The variant shown in Fig. 3 comprises a number of lighting units 11 from Fig. 2 arranged in a line or array. The light beams 19 emitted by the individual lighting units 11 have the same main radiation direction H. The light beams 19 can also be collimated by additional collimation optics 35, in particular lenses, in a second direction which runs perpendicular to the image plane in the illustration in Fig. 2. This results in a point-like or circular imaging of the emitted radiation 19 in the far field behind the optics 35.

[0149] The use of photonic crystals in the illumination device 11 according to Figures 2 and 3 effectively results in a higher resolution compared to a line or array arrangement of the illumination device 11 according to Figure 3. Furthermore, a smaller beam cross section can be realized, especially in the far field downstream of the optical system 35. This allows the optical system 35 and possibly further subsequent optical systems to be made more compact, since collimation in the first direction R1 (see Figure 2) occurs solely through the photonic crystal 25 integrated in the illumination device 11.

[0150] In the variant of Fig. 4, the illumination unit 11 comprises a photonic structure 17 which is a two-dimensional photonic crystal 37, the end faces of which form the light exit surface 15. At least one optoelectronic light source, optionally provided with a conversion material, is arranged behind the photonic crystal 37 as seen from the light exit surface 15. The photonic crystal 37 is formed in order to shape the electromagnetic radiation 19 emitted via the light exit surface in such a way as to generate a defined, discrete pattern 39 in the far field 21. In the illustrated example, the pattern 39 consists of a plurality of distributed light points 41, but other patterns are also possible.

[0151] The illumination unit 11 of Figure 4 is suitable for use, for example, in a surface topography detection system 43 illustrated in the block diagram of Figure 5. In addition to the illumination unit 11, the system 43 includes a detection unit 45 with a camera 47 configured to detect the pattern 39 when it illuminates an object (not shown).

[0152] Furthermore, an analysis device 49 is provided which is arranged to ascertain the deviation of the pattern 39 with respect to a predefined reference pattern which can for example be determined from the detection of the projection of the pattern 39 onto a flat surface.

[0153] The analysis device 49 is further configured to determine the shape and / or structure of an object illuminated by the pattern 39 in the far field 21 depending on the determined deviation of the pattern 39. Thus, by means of this system 43, for example, face detection can be realized.

[0154] In the variant of Figure 4, downstream optics for pattern generation can be omitted, since the pattern 39 is already generated by the photonic crystal 37. The illumination device 11 according to Figure 4 and thus the system 43 according to Figure 5 can therefore be realized in a particularly compact manner.

[0155] FIG. 6 shows a lighting unit 1 with an emitter unit 2 having a light exit surface 3 to which a polarizing element 4 is applied in the form of a polarizing layer with a three-dimensional photonic structure. According to the configuration example shown in FIG. 6, the emitter unit 2 is an LED 5 that emits light in the visible or possibly ultraviolet wavelength range. The light emitted by the LED 5 is guided to the three-dimensional photonic structure, where it is polarized in a certain vibration direction depending on the configuration and dimensions of the structure. Depending on the configuration of the three-dimensional photonic structure, circular or linear polarization can occur. It is important that only light with a certain polarization is emitted from the lighting unit 1.

[0156] 7, circular polarization occurs when the three-dimensional photonic structure of the polarizing element 4 has helical structural elements 6. On the other hand, if the structural elements of the three-dimensional photonic structure are rod-shaped, in particular those called nanorods, linear polarization of the radiation guided through the three-dimensional photonic structure results.

[0157] The lighting unit 1 shown in Fig. 6 is manufactured by a two-photon lithography process, an oblique deposition process, laser interference lithography or holographic patterning. In this connection, it should be noted that the helical structural element 6 shown in Fig. 7 has been manufactured using an oblique deposition process.

[0158] As shown in Fig. 6, the illumination unit 1 can be advantageously combined with further illumination units having complementary properties, such that illumination units 1 having different polarization and / or transmission properties are combined for image generation.

[0159] The radiation polarized in different vibration directions, generated by a number of illumination units with in each case complementary properties, is imaged onto a display or screen by means of a common optical system. Such a device can be advantageously used for applications in which three-dimensional images are created.

[0160] As shown in FIG. 6, by using a three-dimensional photonic structure formed with a polarizing element 4 and arranged on the surface or light exit surface 3 of the LED chip, it is possible to generate light with fundamentally different properties compared to currently known LEDs, in particular with a defined polarization. Here, the provision of a three-dimensional photonic structure on the chip surface has the great advantage that no additional optical components, such as for example conventional polarizing filters, are necessary. The lighting unit can therefore be constructed relatively small. Being patterned directly on the semiconductor chip of the LED 5, such a lighting unit 1 is also more energy-efficient than known lighting units, in which the selection of the polarization takes place at a later point in time. Each photon that fails to pass through the three-dimensional photonic structure due to its properties remains in the LED chip and can be emitted anew by a reabsorption process.

[0161] FIG. 8 shows an illumination unit 1 comprising an emitter unit 2 having a light exit surface 3 to which is applied a polarizing element 4 having a three-dimensional photonic structure with wavelength-selective properties.

[0162] In this case, the photonic structure is constructed as a three-dimensional photonic crystal, or it can be constructed by stacking several two-dimensional photonic crystals one on top of the other.

[0163] The three-dimensional photonic structure is configured to have wavelength-specific transmittance and polarization properties, meaning that the transmittance and polarization properties of the three-dimensional photonic structure vary with the wavelength of the incident radiation.

[0164] The lighting unit 1 shown in Fig. 8 has an emitter unit, which also has an LED 5. Furthermore, a conversion element 7 is provided which has a layer of a conversion material. Upon excitation by excitation light 8 emitted by the LED 5, the conversion material emits converted radiation 9 having a wavelength different from the wavelength of the excitation light 8.

[0165] When both the unconverted excitation light 8 and the converted emission 9 hit the 3D photonic structure, they are affected differently depending on their wavelength in terms of transmission and polarization. As can be seen in Figure 8, the converted emission 9 is extracted perpendicular to the surface of the LED chip, while the excitation light 8 is deflected laterally.

[0166] Such lighting units can preferably be used in components in which radiation with different wavelengths is generated, where different functions can be realized by combining LEDs with conversion elements. Depending on the configuration of the three-dimensional photonic structure and the wavelength of the excitation light 8 emitted by the LED in each case, it is possible to completely suppress the excitation light 8, while the converted radiation 9 radiates through the three-dimensional photonic structure. It is also conceivable to polarize the excitation light 8, while the converted radiation 9 is extracted perpendicularly to the chip surface, as shown in FIG. 8. Of course, this mechanism can also be reversed. It is further conceivable to polarize the converted radiation 9 in a special way, while the excitation light 8 exits unchanged through the chip surface. Here again, the mechanism can also be reversed.

[0167] 9 comprises an emitter unit, again in the form of an LED 15, and a three-dimensional photonic structure 11, for example configured as a spiral. The structure 11 is filled with a conversion material 13.

[0168] 10 shows a top view and a cross-sectional view of a radiation source 6 comprising an LED and a layer 2 arranged on a semiconductor substrate 8 of the LED 7, the layer 2 having structures 4 with a suitable conversion material. The patterned layer 2 with the conversion material forms a conversion element 1, which emits converted radiation into the emission area 3 of the radiation source 6 when excited by excitation light emitted by the LED 7.

[0169] The structures 4 provided in the layer 2 with conversion material are configured in such a way that the converted radiation is emitted exclusively in a specific emission area 3 as a directional beam flux.

[0170] According to the configuration example shown in FIG. 10, the converted radiation is emitted in a direction perpendicular to the plane in which the LED chip is disposed together with its semiconductor substrate.

[0171] The patterning layer 2 shown in Fig. 10 is a two-dimensional photonic crystal etched into the LED semiconductor substrate. The individual, here rod-shaped, recesses of the structures 4 are filled with a conversion material. The layer thickness of the structures 4 is at least 500 nm, which results in a band gap in the crystalline solid material and thus in a directional emitted converted radiation from the conversion element 1.

[0172] Such photonic structures can significantly improve the directivity and therefore the efficiency, especially for etendue-limited systems.By providing the corresponding structures 4 and the layer 2 with the appropriate conversion material directly on the surface of the LED 7, it is possible to eliminate the need for additional optical elements that would otherwise be provided, and thus to realize a relatively small constructed radiation source using the present invention.

[0173] The radiation source 6 shown in FIG. 10 can also be used to realize very small components, for example pixelated LED arrays for high resolution displays, or integrated components, for example in the field of consumer electronics.

[0174] Otherwise, a particularly energy-efficient radiation source is provided, since, on the one hand, light is not emitted in unwanted directions that are not arranged perpendicular to the surface of the LED chip, and, on the other hand, the entire converted light can be utilized. Furthermore, even the mode of excitation light emitted by the LED 7, which is directed to the active zone 9 and has a low extraction efficiency from the LED 7, can be efficiently converted in this way.

[0175] Additionally, Figure 11 shows a cross-sectional view of a radiation source 6 which is constructed as explained in relation to Figure 10, but which additionally comprises a filter element in the form of a filter layer 5 which is opaque to radiation in a selected wavelength range and which is applied to the top of the radiation source 6. In this case, the filter layer 5 has the function of a color filter.

[0176] Such a technical configuration is found in particular in radiation sources 6, in which LEDs 7 are combined with the conversion element 1 in such a way that the light emitted by the LEDs 7 is completely converted. By means of a suitably configured filter layer 5, the radiation emitted in the emission area 3 can be limited to radiation of a desired wavelength. Likewise, by means of such a filter layer 5, it is ensured that the filter layer 5, if necessary, prevents excitation light emitted by the LEDs 7 that has not been converted into converted radiation by the conversion element 1 from emitting in the emission area 3.

[0177] Figure 12 again shows a radiation source 6 with an LED 7 and a conversion element 1 applied to a semiconductor substrate 8 of the LED 7. The conversion element 1 comprises a layer 2 with a conversion material and a structure 4 applied to the semiconductor substrate 8 of the LED 7. The patterning layer 2 is preferably a photonic crystal, a quasi-periodic or a deterministic aperiodic photonic structure. The structure 4 of the layer 2 is filled with a suitable conversion material.

[0178] However, in contrast to the configuration example described in Fig. 10, the patterning layer 2 is not only arranged on the semiconductor substrate in the region above the radiation source 6, but also extends into the active zone 9 of the LED 7. Here too, a patterning layer 2 having a layer thickness of more than 500 nm is provided, thus creating an optical band gap. Again, this allows efficient conversion of the mode of the excitation light emitted by the LED 7, which is guided to the active zone 9 and has a low extraction efficiency from the LED.

[0179] Complementarily, Fig. 13 shows the configuration of a radiation source 6 as configured as in Fig. 12, with additionally a filter element 5 applied to the top layer of the radiation source 6, configured in the form of a filter layer acting as a color filter. Such a color filter offers the possibility to limit the emission of the converted radiation within the emission range in case of complete conversion of the excitation light emitted by the LED 7, or to selectively suppress the emission of unconverted excitation light in case of incomplete conversion.

[0180] An example of one possible configuration of the proposed device is shown in Fig. 14. According to Fig. 14, a semiconductor body with a first material 1, which can also be called a die, is shown, here formed as a light-emitting diode.

[0181] An extraction structure A is formed. A surface region 9 of the semiconductor body which provides the device is provided with a planarized surface 7. The surface region 9 is patterned for this purpose and subsequently planarized.

[0182] The semiconductor body can be produced epitaxially, such that the surface region 9 is produced facing a carrier, not shown. In principle, all surface regions of the semiconductor body which provides the device can be patterned and subsequently planarized to form the extraction structure A, in particular the optical extraction structure A. Electromagnetic radiation of other wavelengths can also be extracted, provided that the patterning and planarization are matched thereto.

[0183] 14 shows patterning of a surface region 9 of a semiconductor body, where a random topology is generated in the surface region 9. Here, the random topology is formed by directly roughening the first material 1 of the semiconductor body on the surface region 9.

[0184] Here, topology refers specifically to spatial structures.

[0185] A transparent third material 5 with a low refractive index, in particular below 1.5, is then applied to planarize the surface region 9 of the semiconductor body. This is followed by a thinning of the applied transparent third material 5 with a low refractive index until the highest peaks of the first material 1 of the semiconductor body are flat and / or smooth at the surface 7 of the patterned surface region 9. The third material 5 can be applied as a layer.

[0186] The thinning can be accomplished by chemical mechanical polishing (CMP).

[0187] Possible structures embossed into the surface region 9 may be random topologies, such as for example roughened surfaces. Random topologies, such as for example roughened surfaces, are already used in large LEDs.

[0188] Light extraction is improved by the extraction structure A having a planarized surface 7. For this purpose, the first material 1, for example of an LED semiconductor or LED die, is first directly patterned as in FIG.

[0189] A transparent third material 5 with a low refractive index used for planarization can be SiO2, which can in particular be provided by TEOS (tetraethyl orthosilicate).

[0190] The refractive index (Brechungsindex), also called the refractive index (Brechzahl) or optical density, and formerly called the refractive index (Brechungszahl), is a property of an optical material. It is the ratio of the wavelength of light in a vacuum to the wavelength in the material, and thus the ratio of the phase velocity of light in a vacuum to the phase velocity in the material. The refractive index is dimensionless and generally depends on the frequency of the light, which is called dispersion. At the interface between two media with different refractive indices, light is refracted or reflected. A medium with a higher refractive index is called optically dense.

[0191] A low refractive index can in particular be less than 1.5. Other usable materials with low refractive index are, for example, crown glass with a refractive index of, for example, 1.46, PMMA with a refractive index of, for example, 1.49, and quartz glass with a refractive index of, for example, 1.46. These refractive indices occur at the wavelength of the sodium D line of 589 nm. The refractive index of silicon dioxide is, for example, 1.458. Other materials can be used as well.

[0192] The same reference numbers in all figures refer to the same features.

[0193] FIG. 15 shows a second example configuration of the proposed device.

[0194] To improve the light extraction, instead of the configuration example according to Fig. 15, a transparent second material 3 with a high refractive index can be applied to the light-emitting diode and patterned in a suitable manner. A suitable second material 3 with a high refractive index is, for example, Nb2O5. These alternatives are shown in Figs. 15 and 16.

[0195] A high refractive index may in particular be greater than 2. Other usable high refractive index materials include, for example, zinc sulfide with a refractive index of, for example, 2.37, diamond with a refractive index of, for example, 2.42, titanium dioxide with a refractive index of, for example, 2.52, silicon carbide with a refractive index of, for example, 2.65, and titanium dioxide with a refractive index of, for example, 3.10. These refractive indices occur in particular at the wavelength of the sodium D line, 589 nm. For example, the refractive index of niobium (V) oxide is 2.3. Other materials may also be used.

[0196] In a surface region 9 of the semiconductor body providing the device, an extraction structure A is formed. Similarly, a patterning of the surface region 9 also takes place here.

[0197] The patterning of the surface region 9 is performed by generating a random topology in the surface region 9, as in the case of figure 14. According to figure 14, the generation of the random topology is performed by directly roughening the surface 7 of the surface region 9 with the first material 1, whereas according to figure 15, the random topology is formed by applying a transparent second material 3 having a high refractive index, in particular a refractive index greater than 2, in particular in the form of a layer to the surface region 9 and roughening the second material 3.

[0198] This is followed by planarization, in particular by layer-wise application of a transparent third material 5 having a low refractive index, in particular below 1.5, to the patterned surface region 9. The third material 5 can be applied as a layer. A thinning of the applied transparent third material 5 having a low refractive index can then be performed until the highest peaks of the second material 3 having a high refractive index at the surface 7 of the patterned surface region 9 are flat and / or smooth.

[0199] A transparent third material 5 with a low refractive index can be SiO2, in particular provided by TEOS (Tetraethylorthosilicate). Thinning can be performed by chemical mechanical polishing (CMP).

[0200] FIG. 16 shows an example of the configuration of the proposed device.

[0201] Alternatively, an ordered topology can be generated in the surface region 9 in order to pattern the surface region 9 .

[0202] In this case, an ordered topology is generated by applying a transparent second material 3 having a high refractive index, in particular a refractive index greater than 2, to the surface region 9, in particular in the form of a layer, and patterning periodic photonic crystals or aperiodic photonic structures, in particular quasi-periodic or deterministic aperiodic photonic structures, in the second material 3.

[0203] Alternatively, it is in principle also possible to pattern periodic photonic crystals or aperiodic photonic structures, in particular quasi-periodic photonic structures or deterministic aperiodic photonic structures, directly into the first material 1 of the semiconductor body without the second material 3. In this case, a device with an extraction structure A can be formed, in which the semiconductor first material 1 of the structural element is provided with a transparent third material 5 with a low refractive index, in particular SiO2, and the first material 1 can be patterned with periodic photonic crystals or aperiodic photonic structures, in particular quasi-periodic or deterministic aperiodic photonic structures.

[0204] Photonic crystals consist of patterned semiconductors, glasses or polymers and are usually manufactured by methods known from microelectronics. Their special structure allows light to propagate through the medium in the way required for the function of the component. This allows light to be guided, on the order of magnitude of the wavelength, but also to be filtered and wavelength-selectively reflected.

[0205] These are periodic dielectric structures whose periodic length can be adjusted to affect the propagation of electromagnetic waves in the same way that periodic electric potentials affect the propagation of electrons in semiconductor crystals, and so they exhibit unique optical properties, such as Bragg reflection of visible light.

[0206] In particular, similar to the formation of an electronic band structure, a photonic band structure is formed, which can have a forbidden energy region (photonic band gap, PBG) in which electromagnetic waves cannot propagate within the crystal. In other words, photonic crystals can be regarded as the optical analogue of electronic semiconductors, that is, "optical semiconductors."

[0207] After patterning of the periodic photonic crystal or aperiodic photonic structure, in particular a quasi-periodic or deterministic aperiodic photonic structure, a transparent third material 5 with a low refractive index is applied, in particular in the form of a layer, to the patterned surface area 9 and planarized. Suitable for this purpose is, for example, SiO2 deposited with the aid of TEOS (tetraethyl orthosilicate). The third material 5 is subsequently thinned until the highest peaks of the second material 3 with a high refractive index at the surface 7 are smoothed out.

[0208] A suitable process for thinning is CMP (Chemical Mechanical Polishing), which uniformly removes layers with thicknesses in the micrometer and nanometer range. The result is a flat and / or smooth surface. The roughness is in particular in the range of a few nanometers as average roughness value (rms). The produced planarized surface 7 can be used to transfer light-emitting diodes using conventional stamping techniques.

[0209] In this way, the removal efficiency can be improved compared to untreated surfaces. Transfer processes using stamping techniques remain further possible.

[0210] FIG. 17 shows an example of a configuration of the proposed method.

[0211] In a first step S1, a surface region 9 of the semiconductor body providing the device is patterned to form an extraction structure A. In a second step S2, the patterned surface region 9 is planarized to obtain a planarized surface 7 of the surface region 9. This planarization comprises two sub-steps.

[0212] According to a first substep S2.1, a transparent third material 5 having a low refractive index, in particular less than 1.5, is applied to the patterned surface region 9, in particular in the form of a layer.

[0213] The second substep S2.2 involves thinning the provided transparent third material 5 with a lower refractive index until the highest peaks of the first material 1 of the semiconductor body or the highest peaks of the second material 3 with a higher refractive index at the surface 7 of the patterned surface region 9 are flat and / or smooth.

[0214] In a third step S3, the transfer of the device can be carried out using stamping techniques, in which the semiconductor body is lifted up from the planarized surface 7.

[0215] In all of the configuration examples described below, the semiconductor materials used may in particular be the material systems GaN, AlInGaP, AlN or InGaAs.

[0216] 18a and 18b show an optoelectronic device for emitting light, preferably perpendicularly, from a light output surface 21. The device comprises an array 11 with pixels, in which optically active nanostructures in the form of photonic crystals K are formed over the entire light emitting surface of the light output surface 21. Furthermore, the array 11 comprises an array of light sources, each with a recombination zone 2 located at the recombination surface 1.

[0217] The recombination zone 2 is formed in a first layer of optically active semiconductor material 3 of the array 11. In this layer with semiconductor material 3, photonic crystals or photonic crystal structures K are patterned, i.e. in the form of two-dimensional photonic crystals. Here, the photonic crystals K are arranged between the recombination zone 2 and the light exit surface 21. In this respect, the photonic crystal structures K may be arranged independently of the position of the individual pixels, in the illustrated example one pixel corresponding to one light source with the recombination zone 2.

[0218] The optically active photonic crystal structure K is free-standing in air or, as shown, is filled with a first filling material 7, in particular SiO2, which is in particular electrically insulating and optically transparent, having a refractive index smaller than the refractive index of the semiconductor material 3. The filling material 7 also advantageously has a small absorption coefficient.

[0219] In order to electrically contact the light sources in the array 11, the two electrical poles of each light source are electrically connected by an optically reflective contact layer 5. The contact layer 5 is located on the side of the optically active semiconductor material 3 that does not face the optically active photonic crystal structure K and is arranged at the bottom as shown in FIG. 1b. Such a contact connection results in a very strong and localized recombination zone 2. Here, the contact layer 5 has at least two regions that are electrically insulated from each other so that the electrically separated poles can be connected.

[0220] The photonic crystal K can be patterned over the entire light emitting surface 21 such that only light can leave the component having a propagation direction at least approximately perpendicular to the surface 21. If the photonic crystal K is close to the recombination surface 1 and the layer thickness of the photonic crystal K is large compared to the distance to the recombination zone 2, the optical density of states in the light generation region is further modified.

[0221] In this way, a complete band gap of optical modes with a propagation direction parallel to a particularly flat, i.e. particularly planar and / or smooth, surface of the pixelated array 11 can be generated, whereby the emission of light with a propagation direction parallel to the light emitting surface is completely suppressed.

[0222] In particular, light can be generated only within a limited emission cone specified by the photonic crystal K. In this case, the directionality is already ensured at the light generation stage, which effectively increases the efficiency compared to angle-selective optics that only affect the light extraction.

[0223] The orientation of the photonic crystal K is independent of the location of the individual pixels, and no particular orientation of the pixel structure relative to the photonic structure K is required, allowing processing of the entire surface of the wafer.

[0224] It is advantageous if the device has uniform optical properties across the array 11, or which vary only slightly so as not to disturb the optical environment of the photonic crystal K.

[0225] Figures 19a and 19b show a second proposed optoelectronic device in plan view and cross-section, respectively. In the pixelated array 11, the photonic crystal K is arranged in a second layer of material 9, in particular Nb2O5, on top of a first layer of optically active semiconductor material 3, as an alternative to the configuration example shown in Figures 18a and 18b. Here, material 9 has a large optical refractive index and is arranged on a planar and / or smooth surface of semiconductor material 3. Advantageously, material 9 also has low absorption.

[0226] The photonic crystal K may also be formed as a free-standing two-dimensional photonic crystal from the aforementioned material 9, where the free space is air. The free space may thus be filled with a material 7 having a lower refractive index. The filling material may be, for example, SiO2.

[0227] The contact connections here are similar to those shown in FIGS. 18a and 18b and allow for a very localized recombination zone 2.

[0228] Figures 20a and 20b show a third proposed optoelectronic device in plan view and cross section, respectively. The device shown comprises as a light source an arrangement of vertical light-emitting diodes 13 and, arranged in an overlying layer, a two-dimensional photonic crystal structure K extending under the entire light-emitting surface 21 and made of a material 9 with a high refractive index. The gaps of the structure K are filled with a filling material 7, which again has a low optical refractive index.

[0229] The vertical light emitting diode 13 has upper and lower electrical contacts along a vertically oriented longitudinal axis that runs perpendicular to the light output surface 21. Thus, the light emitting diode has an electrical contact on the front side and also on the back side. Here, the side of the LED 13 that does not face the light output surface 21 is referred to as the back side, while the front side faces the light output surface 21.

[0230] The device comprises an electrically conductive, light-reflecting contact layer 5 for electrically connecting the rear contacts of the LEDs 13. A third layer of an electrically conductive, optically transparent material 17, for example ITO, is provided for electrically connecting the front contacts of the LEDs 13. Via bonding wires 19, an electrical connection can be made with the corresponding poles of a current source.

[0231] In and along the recombination surface 1 a further, in particular electrically insulating, filler material 15 may be arranged between the third layer and the optically reflective contact layer 5 .

[0232] Figures 21a and 21b show a fourth proposed optoelectronic device in plan and cross-sectional views. The device comprises an arrangement of lateral light emitting diodes (LEDs) 13 with their respective recombination zones 2 and an optically active two-dimensional photonic crystal structure K underlying the entire light emitting surface 21. The photonic crystal structure K is in a layer of a material 9 with a high refractive index, e.g. Nb2O5. The gaps are also filled with a filling material 7 with a low optical refractive index, e.g. silicon dioxide.

[0233] In the case of a lateral light-emitting diode 13, the two electrical contacts are located on the rear side of the light-emitting diode 13. The two poles of the LED 13 are in each case electrically connected by mutually electrically isolated areas of the optically reflective contact layer 5.

[0234] In the region of the recombination surface 1 , between the material layer 9 and the contact layer 5 a filling material 15 , in particular an electrically insulating filling material 15 , is arranged.

[0235] The efficiency of the light generation can be relatively high in the configurations according to Fig. 18a-21b, because in these configuration examples, the light directionality or directional property can already be achieved during the light generation, especially if the band structure of the photonic crystal K allows a higher density of photonic states to be achieved in the region of the recombination zone 2 for the emission of light perpendicular to the light exit surface. Furthermore, the patterning of the photonic crystal K can have the advantage that it can be performed uniformly over the entire wafer. No specific positional or orientational relationship is required between the photonic crystal and the individual pixels or light-emitting diodes. This can significantly reduce the manufacturing effort, especially compared to alternative approaches in which structures are individually placed at each pixel.

[0236] Figures 22a and 22b show in plan and cross-section a fifth proposed optoelectronic device. The device includes a pixelated array 11 and an optically active pillar structure P, in particular a structure having pillars or columns patterned across an emitting surface 21. The array 11 is preferably smooth and flat.

[0237] The pixelated array 11 comprises pixels each with one light source comprising a respective recombination zone 2 located in a recombination plane 1, said zone being arranged in a first layer comprising an optically active semiconductor material 3.

[0238] On this first layer, pillar structures P are formed, where the pillars P are assigned to light sources, such that each pillar P is arranged directly above the recombination zone 2 of the assigned light source 2. In this regard, the longitudinal axis L of each pillar P passes in particular through the center M of the recombination zone 2 of the assigned light source 2.

[0239] The pillars P consist of a material 9 with a high refractive index, for example Nb2O5. In the spaces between the columns P, a filling material 7 with a low refractive index, for example silicon dioxide, may be placed.

[0240] The pillars P may be arranged above the layer with the light sources, in particular by additionally applying the pillars P above the array 11. Alternatively, the pillars can be etched into the semiconductor material 3. For this purpose, the semiconductor material layer can be configured with a corresponding height. Since the semiconductor material usually has a high refractive index, material can be etched away to leave the pillars 9. The areas vacated by the etching can be filled with a material with a lower refractive index.

[0241] Since the pillars P act like waveguides that guide the light upwards in the direction of the longitudinal axis L, the pillars P can improve the emission of light in a direction perpendicular to the light exit surface 21 .

[0242] In the array 11, the two electrical poles of the light sources are in each case electrically connected by a reflective contact layer 5 in order to make an electrical contact between the light sources and the recombination zone 2. The contact layer 5 is formed on the side of the semiconductor material that does not face the optically active pillar structure P. The contact layer 5 can have two separate areas so that the two poles can be electrically contacted separately from one another. Such a type of contact leads to a very strong and localized recombination zone 2.

[0243] 23a and 23b show a sixth proposed optoelectronic device in plan and cross-sectional views. The device comprises an arrangement of vertical light-emitting diodes 13, also called LEDs, on top of which an optically active pillar structure P, in particular having a pillar or column, is arranged, with the longitudinal axis L of the pillar P passing at least substantially through the centre point of the recombination zone 2 of the LEDs 13.

[0244] The pillar structure P may be free-standing in air or may be filled with a first, in particular electrically insulating and optically transparent, filling material 7 and arranged above the light-emitting diodes. The filling material 7 may have a refractive index smaller than the refractive index of the material 9 of the pillar P and / or the semiconductor material 3 of the LED 3.

[0245] As already mentioned, the LEDs are vertical light emitting diodes 13. They have one, particularly positive, electrical pole on their rear side facing the reflective contact layer 5 and another electrical pole on their front side facing the pillar P.

[0246] The pole on the front side of the light source is electrically connected to a corresponding current supply circuit (not shown) by a layer of electrically conductive and optically transparent material 17, in particular ITO, and by contact wires 19. The layer with material 17 is disposed between the light source and the pillar 17 as shown.

[0247] Thereby, the second filler material 15 may be disposed in gaps within the layers of the LED 13 and thus between the layer with material 17 and the contact layer 5 .

[0248] The dimensions of the pillar structures P may correspond to the dimensions of a light emitting diode 13 or a pixel of the array 11 .

[0249] Figures 24a and 24b show the seventh proposed optoelectronic device in plan view and cross-section. Unlike the variants of Figures 23a and 23b, the device according to Figures 24a and 24b comprises an arrangement of lateral light-emitting diodes 13, the electrical poles of which are arranged on the back side of the light-emitting diodes 13. Thus, for electrical contact connection, the electrical poles of the light source can be electrically connected through two electrically separated areas of the reflective contact layer 5. Therefore, no intermediate layer with material 17 is required as in the variant with vertical light-emitting diodes described above.

[0250] 18 to 21, the pillar P variant has a significantly larger structure size of up to 1 μm in diameter and can therefore be more easily manufactured using standard techniques. Therefore, the process requirements are low and high-resolution lithography is sufficient to manufacture the pillars.

[0251] Pillar structures, in particular pillars or columns, made of an optically active semiconductor material 3 or a material 9 with the highest possible refractive index can be precisely patterned above the individual pixels of the array 11 or above the vertical light-emitting diodes 13 (FIGS. 23a and 23b) or above the horizontal light-emitting diodes 13 (FIGS. 24a and 24b). The individual pixels or light-emitting diodes 13 may have a diameter of less than 1 μm and the pillars may have an aspect ratio height:diameter of at least 3:1. The pillars are advantageously etched directly into the semiconductor material 3, as is possible in FIGS. 22a and 23b as well as in FIGS. 24a and 24b, since according to FIG. 23b no third layer 17 is formed, or the pillars are made of another material 9 with a high refractive index and advantageously low absorption, which is applied to the surface of the array 11. A material with a high refractive index can be, for example, Nb2O5. The pillar structures can be free-standing or filled with a material 7 with a low refractive index. An example of a low refractive index filling material is SiO2. The refractive index of the pillar is higher than that of the surrounding material, which enhances the emission parallel to the longitudinal axis of the pillar compared to other spatial directions. Due to the waveguide effect, light along the longitudinal axis of the pillar is extracted more efficiently than light having other propagation directions. This can improve the directivity or directionality of the emitted light.

[0252] Figures 25a and 25b show in plan and cross-sectional views an eighth proposed optoelectronic device, which comprises an arrangement of light-emitting diodes 13, each formed as a pillar P and thus in the shape of a column.

[0253] The length of the pillars P corresponds to half the wavelength of the light emitted in the semiconductor material 3, and the recombination zone 2 may advantageously be located at the center M of each pillar and thus at a local maximum of the photonic density of states. The pillars P may have an aspect ratio of height:diameter of at least 3:1.

[0254] In the illustrated arrangement, the pillars P may be approximately 100 nm high and only approximately 30 nm in diameter, which requires very fine resolution patterning techniques that are difficult to translate at wafer level with current manufacturing techniques.

[0255] Alternatively, the dimensions can be scaled up for ease of manufacture, in which case the emitted light becomes less directional as the size of the pillar patterning increases. The length of the pillar P is preferably a multiple of half the wavelength of the emitted light in the semiconductor material, and each recombination zone 2 can be located at a maximum of the photonic density of states.

[0256] Due to the pillar patterning of the LEDs 13, the light emission parallel to the longitudinal axis of the pillars P is effectively enhanced due to a larger density of photonic states. Due to the waveguide effect, light having a propagation direction along the longitudinal axis of the pillars P is extracted more efficiently than light having other propagation directions. The space between the pillars P is filled with a material 7, which advantageously has a very small absorption coefficient and a refractive index smaller than that of the semiconductor material 3. A filling material with a small refractive index could be, for example, SiO2.

[0257] In this arrangement of light-emitting diodes 13 shaped as pillars P or columns, in particular vertical light-emitting diodes 13, a first pole, in particular the positive first pole, is in each case electrically connected by a reflective contact layer 5 for contact-connecting to a recombination zone 2 arranged in the recombination surface 1. The contact layer 5 is formed at a lower first longitudinal end of the light-emitting diode 13.

[0258] The other, in particular the negative, second pole in each case is electrically connected to a third layer of conductive transparent material 17, in particular ITO, and is connected by a bonding wire 19, for example to a corresponding pole of a current supply circuit.

[0259] According to this arrangement, the third layer is formed in and along the recombination surface 1 at the longitudinal centre of a light emitting diode 13 shaped as a pillar P or column.

[0260] Figures 26a and 26b show a ninth proposed optoelectronic device in plan and cross-sectional views. In contrast to the variant of Figures 25a and 25b, the device according to Figures 26a and 26b has a vertical LED formed as a pillar P.

[0261] A lower electrical contact, in particular a p-type contact, is established via the lower surface of the pillar P, in particular by contact connection to the contact layer 5 .

[0262] The top electrical contact, in particular the n-type contact, is on the upper side of the pillars P. This contact is established via a top layer with an optically transparent and electrically conductive material 17. The top layer extends over the pillars P and a first filling material 7 that fills the gaps between the pillars P. The top layer material 17 can be, for example, ITO (indium tin oxide). Via bonding wires 19, a connection to a current supply circuit can be established.

[0263] By electrically contacting the light emitting diodes within the pillars P, a very strong localized recombination zone 2 is created, and a top contact, in particular an n-type contact, can be made at the level of the recombination zone 2 or on the upper side of the pillars P. Each pillar P creates an individual pixel.

[0264] The light emission parallel to the longitudinal axis of the pillar-shaped light-emitting diode 13 according to Figures 25a-26b is enhanced, which improves the directionality of the emitted light compared to conventional low aspect ratio light-emitting diodes. Compared to the arrangement according to Figures 22a-24b, the arrangement according to Figures 25a-26b can significantly affect the light generation process, thereby achieving high directionality and efficiency.

[0265] 27 shows a cross-sectional view of a further optoelectronic device in which a two-dimensional photonic crystal K is arranged on top of a layer in which an array of light sources with a recombination zone 2 is arranged. In this case, the photonic crystal K is arranged in the region close to the recombination zone 2 in such a way that it changes the optical density of states present in the region of the recombination zone 2, in particular in such a way that a band gap of at least one optical mode having a propagation direction parallel and / or at a small angle to the light output surface 21 is created and / or the density of states of at least one optical mode having a propagation direction perpendicular to the light output surface 21 is increased.

[0266] This is achieved in particular by the height H of the photonic crystal K being at least 300-500 nm, preferably at most 1 μm. The height H of the photonic crystal may depend on the high refractive index material of the photonic crystal.

[0267] Furthermore, preferably, the distance A between the center M of the recombination zone 2 and the lower surface of the photonic crystal K is at most 1 μm, preferably a few nm.

[0268] All configurations described with photonic crystals K are advantageously two-dimensional photonic crystals with a periodic variation of the optical refractive index in two mutually perpendicular spatial directions extending parallel to the light exit surface, and even more advantageously pillar structures in which pillars P or columns are arranged in an array such that the longitudinal axes L of the pillars P extend perpendicular to the light emitting surface 21.

[0269] Possible fields of application for the devices described herein are, for example, the automotive sector, lighting of all kinds, household appliances and video walls.

[0270] Features mentioned in connection with one embodiment and / or claim may be combined with other embodiments and / or claims even if the features are not mentioned in connection with other embodiments and / or claims.

Claims

1. 1. A lighting unit, comprising: at least one photoelectron emitter unit (13) emitting electromagnetic radiation (19) via a light exit surface (15); a photonic structure (17) for beam shaping said electromagnetic radiation (19) before said electromagnetic radiation (19) exits through said light exit surface (15); Including, An illumination unit, wherein the photonic structure (17) shapes the electromagnetic radiation (19) such that the electromagnetic radiation (19) has a specific far-field (21).

2. 2. The lighting unit according to claim 1, wherein the photonic structure (17) is a one-dimensional photonic structure, in particular a one-dimensional photonic crystal (25).

3. 3. The lighting unit according to claim 1, wherein the photonic structure (17), in particular as a one-dimensional photonic crystal (25), is configured such that the emitted electromagnetic radiation (19) is at least approximately collimated in a first spatial direction (R1).

4. 4. The lighting unit according to claim 3, further comprising a collimation optical system (35) arranged downstream of the light exit surface (15) as viewed in the main radiation direction (H), the optical system (35) being formed to collimate the electromagnetic radiation (19) in a further second spatial direction (R2) extending perpendicular to the first spatial direction (R1).

5. 5. The lighting unit according to claim 1, wherein the photonic structure (17), in particular the photonic structure (17) formed as a one-dimensional photonic crystal (25), is formed such that the main radiation direction (H) of the electromagnetic radiation (19) extends at an angle (α) to a normal (N) of the light exit surface (15), wherein the angle (α) is not 0°.

6. 6. The lighting unit according to claim 5, wherein the photonic structure (17) formed as a one-dimensional photonic crystal (25) is arranged in a layer below the light exit surface (15), the one-dimensional photonic crystal (25) having a periodically repeated sequence extending in a first direction (R1) of two materials (31, 33) with different optical refractive indices, the materials (31, 33) having abutting interfaces extending non-orthogonally and inclined with respect to the light exit surface (15).

7. 2. The lighting unit according to claim 1, wherein the photonic structure (17) is a two-dimensional photonic structure, in particular a two-dimensional photonic crystal (37).

8. 8. The lighting unit according to claim 7, wherein the two-dimensional photonic structure (37) is configured such that the electromagnetic radiation (19) generates a defined, in particular discrete, pattern (39) in the far field (21).

9. the photonic structure (17) is arranged in a layer, in particular a semiconductor layer, beneath the light exit surface (15), and / or the photonic structure (17) is formed in a semiconductor layer of the photoelectron emitter unit (13), and / or 9. The lighting device according to claim 1, wherein the photoelectron emitter unit (13) comprises a layer having a conversion material, and the photonic structure (17) is formed in the layer having the conversion material or in a layer between the layer having the conversion material and the light exit surface (15).

10. 10. The lighting device according to any one of the preceding claims, wherein the photonic structure (17) is a quasi-periodic or deterministic aperiodic photonic structure, in particular instead of a photonic crystal.

11. A surface topography detection system comprising an illumination unit (11), The lighting unit (11) at least one photoelectron emitter unit (13) emitting electromagnetic radiation (19) via a light exit surface (15); A photonic structure (17) for beam shaping said electromagnetic radiation (19) before said electromagnetic radiation (19) exits through said light exit surface (15), wherein: The photonic structure (17) shapes the electromagnetic radiation (19) so that the electromagnetic radiation (19) has a specific far-field (21); said photonic structure (17) being a two-dimensional photonic structure, in particular a two-dimensional photonic crystal (37); The two-dimensional photonic structure (37) is configured such that the electromagnetic radiation (19) generates a defined, in particular discrete, pattern (39) in the far field (21).

1. A surface topography sensing system comprising: The surface topography detection system (43) a detection unit (45), in particular comprising a camera (37), configured to detect said pattern (39) in said far field (21); The surface topography sensing system further comprises:

12. The surface topography sensing system of claim 11, further comprising an analyzer (49) configured to determine deviations of said pattern (39) relative to a predetermined reference pattern.

13. 13. The surface topography sensing system of claim 12, wherein the analysis device (49) is configured to determine the shape and / or structure of the object illuminated by the pattern (39) depending on the determined deviation.

14. A scanner for scanning an object, comprising at least one illumination device according to any one of claims 1 to 10.

15. at least one emitter unit (2) emitting radiation via a light exit surface (3); and a polarizing element (4) at least partially adjacent to said light exit surface (3) and changing the polarization and / or intensity of radiation emitted by said emitter unit (2) as said radiation passes through said polarizing element (4). A lighting unit (1) comprising: The polarizing element (4) has a photonic structure. A lighting unit (1).

16. 16. The lighting unit according to claim 15, wherein the photonic structure is a three-dimensional photonic structure and / or the polarizing element (4) is configured in the form of a layer arranged in at least a partial area of ​​the light exit surface (3).

17. 17. Lighting unit according to claim 15 or 16, characterized in that the emitter unit (2) comprises at least one LED (5).

18. 18. The lighting unit according to claim 15, wherein the emitter unit (2) comprises an LED (5) which emits light, in particular red, green, blue, ultraviolet or infrared light, which enters the polarizing element (4), and the polarizing element (4) polarizes the radiation in a vibration direction when the radiation passes through the polarizing element (4).

19. 19. The lighting unit according to any one of claims 15 to 18, wherein the polarizing element (4) has spiral and / or rod-shaped structure elements (6).

20. 20. The lighting unit according to claim 15, wherein the emitter unit (2) comprises at least one conversion element (7) with a conversion material which emits converted radiation (9) when excited by excitation light (8) emitted by the LED (5).

21. 21. Illumination unit according to any one of claims 15 to 20, characterized in that the polarizing element (4) comprises at least one three-dimensional photonic crystal (11).

22. 22. The lighting unit according to any one of claims 15 to 21, wherein the polarizing element (4) comprises at least two two-dimensional photonic crystals arranged in succession along a beam path of the radiation passing through the polarizing element (4).

23. 23. The lighting unit according to claim 15, wherein the polarizing element (4) has at least two different polarization properties and / or transmittances depending on the wavelength of the radiation passing through the polarizing element (4).

24. 24. The lighting unit according to claim 15, wherein the emitter unit (2) comprises an LED (5) and a conversion element (7) provided with a conversion material which emits converted radiation (9) when excited by excitation light (8) emitted from the LED (5), and wherein the excitation light (8) incident on the polarizing element (4) is polarized differently and / or absorbed with a different strength when it passes through the polarizing element (4) compared to when the converted radiation (9) passes through.

25. 25. The lighting unit according to claim 15, wherein the emitter unit (2) comprises an LED (5), and the three-dimensional structure of the polarizing element (4) is at least partially introduced into a semiconductor layer of the LED (5) adjacent to the light exit surface (3).

26. 26. The lighting unit according to any one of claims 15 to 25, wherein the photonic structure is a three-dimensional photonic structure (11), and a conversion material (13) is arranged within the three-dimensional photonic structure.

27. A method for manufacturing an illumination unit (1) comprising at least one emitter unit (2) emitting radiation via a light exit surface (3) and a polarizing element (4) at least partially adjacent to said light exit surface (3) and for changing the polarization and / or the intensity of radiation emitted by said emitter unit (2) as said radiation passes through said polarizing element (4), comprising: Providing a chip with an LED (5) as an emitter unit (2) and providing a light exit surface (3) of said chip with a particularly three-dimensional photonic structure as a polarizing element (4), in particular by two-photon lithography or oblique deposition, and / or arranging said photonic structure in a semiconductor layer of said LED (5) adjacent to said light exit surface. A method comprising:

28. 28. The method of claim 27, wherein the photonic structure is dimensioned according to the wavelength of the radiation emitted by the LED (5).

29. Use of an illumination unit (1) according to any one of claims 15 to 26 in a device for generating three-dimensional images.

30. 30. Use according to claim 29, of a lighting unit (1) according to any of claims 15 to 26 for computer-aided generation of three-dimensional images.

31. A conversion element (1) for an optoelectronic component, the conversion element (1) having at least one layer (2) with a conversion material which, when excited by incident excitation light, emits converted radiation into an emission region (3), The layer (2) has at least in some areas a structure (4) in which the conversion material is at least partially arranged and which is configured so that the radiation is emitted as a directional beam bundle towards the emission area (3). A conversion element (1).

32. 32. The conversion element according to claim 31, wherein the structure (4) is configured quasi-periodically or deterministically aperiodically.

33. 33. Conversion element according to claim 31 or 32, wherein the layer (2) comprises at least one photonic crystal, a quasi-periodic photonic structure or a deterministic aperiodic photonic structure.

34. 34. Conversion element according to any one of claims 31 to 33, characterized in that the structure (4) has at least one recess in which the conversion material is arranged.

35. 35. Conversion element according to any one of claims 31 to 34, wherein the layer (2) has an optical band gap.

36. 36. Conversion element according to any one of claims 31 to 35, wherein the structure (4) has an average thickness of at least 500 nm.

37. 37. The conversion element according to any one of claims 31 to 36, wherein the layer (2) having the structures (4) is configured such that the directional beam bundle is emitted perpendicular to a plane in which the layer (2) is arranged.

38. 38. Conversion element according to one of claims 31 to 37, characterized in that an optical filter element (5) is arranged on at least one side of the layer (2).

39. A radiation source (6) comprising an LED (7) and a conversion element (1) according to any one of claims 31 to 38, The LED (7) is configured to emit excitation light to the conversion element (1), the conversion element (1) having at least one layer (2) with a conversion material. A radiation source (6).

40. 40. The radiation source according to claim 39, wherein the layer (2) is part of a semiconductor substrate (8) of the LED (7).

41. 41. The radiation source according to claim 39 or 40, wherein the structure is formed in the semiconductor substrate (8) of the LED (7).

42. 42. The radiation source according to any one of claims 39 to 41, wherein the structure (4) with the conversion material is configured such that converted radiation is emitted into the emission region (3) in a direction perpendicular to a plane in which the semiconductor substrate (8) is arranged.

43. 43. The radiation source according to any of claims 39 to 42, wherein the structure (4) is at least partially arranged in an active layer (9) of the LED (7).

44. A method for manufacturing a radiation source (6) according to any of claims 39 to 43, characterized in that the structure (4) is formed by at least one etching step in a semiconductor substrate (8) of the LED (7).

45. 45. The method of claim 44, wherein the structure (4) is at least partially filled with the conversion material.

46. A method for producing a device, in particular an electronic component, in particular an optoelectronic component, in particular a light-emitting diode, said method comprising the steps of: A step (S1) of patterning a surface region (9); and Planarizing the patterned surface area (9) to obtain a planarized surface (7) of the surface area (9) (S2). by forming an extraction structure (A) in a surface area (9) of the semiconductor body providing said device. A method comprising:

47. Method according to claim 46, wherein the patterning of the surface region (9) is performed by generating a random topology in the surface region (9).

48. 48. The method according to claim 47, wherein the generation of the random topology is performed by directly roughening the surface (7) of the surface region (9) of the semiconductor body comprising the first material (1).

49. 48. The method according to claim 47, wherein the random topology is generated by applying a transparent second material (3) having a high refractive index, in particular a refractive index greater than 2, to the surface region (9), in particular in the form of a layer, and roughening the second material (3).

50. 47. The method according to claim 46, wherein the patterning of the surface region (9) is performed by creating an ordered topology in the surface region (9).

51. 51. The method according to claim 50, wherein the generation of the ordered topology is achieved by applying a transparent second material (3) having a high refractive index, in particular a refractive index greater than 2, to the surface region (9), in particular in the form of a layer, and patterning periodic photonic crystals or aperiodic photonic structures, in particular quasi-periodic or deterministic aperiodic photonic structures, in the second material (3).

52. The transparent second material (3) having a high refractive index is Nb ２ O ５ 52. The method of claim 49 or 51, comprising:

53. 53. The method according to any one of claims 46 to 52, wherein the planarization is performed by a first substep (S2.1) of applying a transparent third material (5) having a low refractive index, in particular a refractive index below 1.5, to the patterned surface region (9), in particular in the form of a layer.

54. 54. The method according to claim 53, wherein planarization is performed by a second substep (S2.2) of thinning the applied transparent third material (5) having a lower refractive index until the highest peaks of the first material (1) of the semiconductor body or the highest peaks of the second material (3) having a higher refractive index at the surface (7) of the patterned surface region (9) are flat and / or smooth.

55. The transparent third material (5) having a low refractive index is SiO ２ 55. The method according to claim 53 or 54, which comprises the steps of:

56. 56. The method of claim 54 or 55, wherein the thinning is performed by chemical mechanical polishing (CMP).

57. 57. The method according to any one of claims 54 to 56, wherein the transfer (S3) of the device is performed by a stamping technique.

58. In devices, in particular electronic components, in particular optoelectronic components, in particular light-emitting diodes, Patterning (S1) of a surface region (9), and Planarization (S2) of the patterned surface region (9) to obtain a planarized surface (7) of the surface region (9). by providing an extraction structure (A) in a surface region (9) of the semiconductor body providing said device. A device comprising:

59. 59. The device according to claim 58, wherein the planarized surface (7) is flat and / or smooth and has a roughness in the range of less than 20 nanometers, in particular less than 1 nanometer, as an average roughness value.

60. The extraction structure (A) comprises a transparent third material (5) with a low refractive index, in particular SiO.sub.2, deposited on the roughened semiconductor first material (1) of the structural element. ２ 60. The device of claim 58 or 59, comprising:

61. The extraction structure (A) is made of a roughened transparent second material (3) having a high refractive index, in particular Nb ２ O ５ On top of this, a transparent third material (5) with a low refractive index, in particular SiO ２ 60. The device according to claim 58 or 59, wherein the second material (3) is applied to the semiconductor first material (1) of the structural element.

62. The extraction structure (A) is a transparent third material (5) having a low refractive index, in particular SiO, on a transparent second material (3) having a high refractive index. ２ 60. The device according to claim 58 or 59, wherein the second material (3) is applied to the semiconductor first material (1) of the structural element and comprises a periodic photonic crystal or an aperiodic photonic structure, in particular a quasi-periodic or deterministic aperiodic photonic structure.

63. 1. An optoelectronic device, comprising: an arrangement (11) comprising a plurality of light sources for generating light emitted from a light exit surface of the optoelectronic device; At least one photonic structure (K, P) arranged between the light exit surface and the plurality of light sources; The optoelectronic device comprises:

64. 64. An optoelectronic device as claimed in claim 63, wherein the photonic structure is configured to beam shape light generated by the light source, in particular such that the light is emitted at least substantially perpendicularly from the light emission surface.

65. 65. An optoelectronic device according to claim 63 or 64, wherein the photonic structure comprises a photonic crystal (K).

66. 66. An optoelectronic device according to any one of claims 63 to 65, wherein the arrangement structure (11) is an array having a plurality of pixels arranged in a layer as light sources, and a photonic crystal is arranged or formed in the layer.

67. An optoelectronic device as claimed in any one of claims 63 to 65, wherein the arrangement structure (11) is an array having a plurality of pixels arranged in a first layer as light sources, and a photonic crystal is arranged in a further second layer, wherein the second layer is arranged between the first layer and the light exit surface.

68. An optoelectronic device as claimed in any one of claims 63 to 65, wherein the arrangement structure (11) has a plurality of LEDs arranged in a first layer as a light source and a photonic crystal arranged in a further second layer, the second layer being arranged between the first layer and the light exit surface.

69. 69. An optoelectronic device as claimed in any one of claims 63 to 68, wherein each of the light sources has a recombination zone and the photonic crystal is arranged in a region adjacent to the recombination zone such that the photonic crystal changes the optical density of states present in the region of the recombination zone, in particular such that a band gap is created for at least one optical mode whose propagation direction is parallel and / or at a small angle to the light output surface.

70. the photonic crystal (K) is arranged relative to a plane extending parallel to the light exit surface, independent of the position of the light spot, and / or The photonic crystal is a two-dimensional photonic crystal having a periodic change in optical refractive index in two spatial directions perpendicular to each other across the plane.

70. An optoelectronic device according to any one of claims 65 to 69.

71. 71. The optoelectronic device of claim 63, wherein the photonic structure comprises a plurality of pillar structures (P) extending at least partially between the light emitting surface and the plurality of light sources, each one of the pillars being assigned to one light source and aligned so as to be coplanar with the light emitting surface when viewed in a direction perpendicular to the light emitting surface.

72. 72. The optoelectronic device of claim 71, wherein the arrangement structure (11) is an array having a plurality of pixels arranged in a first layer as light sources, and the pillars are arranged in a further second layer, wherein the second layer is arranged between the first layer and the light exit surface.

73. 72. The optoelectronic device of claim 71, wherein the arrangement structure (11) has a plurality of LEDs as light sources arranged in a first layer, and the pillars are arranged or formed in a further second layer, wherein the second layer is arranged between the first layer and the light exit surface.

74. 72. An optoelectronic device according to claim 71, wherein the arrangement (11) is an array having a plurality of pixels as light sources, where each pixel is formed by a respective pillar.

75. A method for manufacturing an optoelectronic device, in particular a device according to any one of claims 63 to 74, comprising the steps of: Providing or manufacturing an arrangement (11) comprising a plurality of light sources for generating light to be emitted from a light output surface of the optoelectronic device; The method further comprising: disposing at least one photonic structure (K, P) between said light exit surface and said plurality of light sources.

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