METHOD FOR MANUFACTURING AN OPTOELECTRONIC ARRANGEMENT AND OPTOELECTRONIC ARRANGEMENT

Abstract

The invention relates to a method for manufacturing an arrangement comprising the following steps: providing a plurality of optoelectronic components, in particular microLEDs, arranged on a substrate, wherein each optoelectronic component of the plurality of optoelectronic components comprises a contact area that is electrically connected to a contact line on the substrate. A dielectric material is arranged on the substrate and the plurality of optoelectronic components such that the dielectric material forms a surface with a plurality of continuous projections, each projection being located above one of the respective optoelectronic components.The dielectric material of the protrusions is partially removed to expose edge regions of the multiple optoelectronic components, and a conductive transparent layer is applied to the exposed edge regions and the dielectric material on the substrate to establish electrical contact with each of the multiple optoelectronic components.

Description

[0001] The present invention relates to a method for manufacturing an optoelectronic arrangement comprising a plurality of optoelectronic components, and to an optoelectronic arrangement. BACKGROUND

[0002] The fabrication of components often requires the installation of optical components on their emission surfaces. While lenses, collimators, and other components are readily available for optoelectronic devices with dimensions on the order of a few hundred micrometers, the fabrication of smaller optoelectronic components, known as microLEDs, is more challenging. Sometimes, such components are placed on a test stand or even on the final substrate and tested prior to completion. While this approach has proven efficient, it is also costly.

[0003] However, the cost-effective and competitive mass production of optoelectronic devices requires efficient and less complex manufacturing steps. The aim of this application is therefore to provide aspects for an improved manufacturing process for optoelectronic devices. SUMMARY OF THE INVENTION

[0004] These and other objectives are addressed by the subject matter of the independent claims. Features and further aspects of the proposed principles are set forth in the dependent claims.

[0005] The present application proposes a novel method for fabricating an array comprising a plurality of optoelectronic components, and in particular microLEDs, thereby achieving improved uniform and efficient light output. The proposed principle allows lenses or other optical elements to be attached directly to the top surface of the optoelectronic components using slightly modified fabrication steps. This enables faster fabrication without additional backend manufacturing steps. Furthermore, the proposed method offers a high level of integration at the wafer level and allows the fabrication of microLED arrays.

[0006] According to the proposed principle, a method for fabricating an arrangement comprises a first step in which a plurality of optoelectronic components, in particular microLEDs, are provided. These optoelectronic components are arranged on the substrate. The substrate may comprise a backplane, a temporary support substrate, or any other rigid or flexible material on which the plurality of optoelectronic components can be placed. Each of the multiple optoelectronic components comprises a contact area. The contact area faces the substrate and is attached to it.

[0007] In some cases, the contact area is electrically connected to a contact line on the substrate. This line may run along the top surface or be connected via vias through the substrate or parts thereof. The line on the substrate may have a contact pad or contact area that is larger than the corresponding contact area of ​​each optoelectronic component. This allows for the arrangement of a large number of components with wider tolerances.

[0008] The multiple optoelectronic components also include an emission surface located essentially opposite the contact surface and the substrate. Therefore, in some cases, the optoelectronic components are implemented as vertical microLEDs, where the contact surfaces for conducting current through the optoelectronic component are arranged on opposite sides of the respective component. In other cases, the optoelectronic components are implemented as horizontal microLEDs, where the contact surfaces for driving the microLED are arranged on the same side and preferably opposite the main emission surface of the component.

[0009] The proposed method further comprises the application of a first dielectric material to the substrate and the surface of the several optoelectronic components, such that the dielectric material forms a surface with several continuous projections. In this context, the term "continuous projection" refers to a projection that does not exhibit a step-like structure, but rather presents a smooth, continuous curve in a cross-sectional view.

[0010] Each protrusion is located above one of the several optoelectronic components. In other words, the surface of the dielectric material arranged on the substrate and the optoelectronic components is not flat and even, but actually comprises several protrusions, the positions of which correspond to the position of the optoelectronic component on the substrate.

[0011] The dielectric material of the protrusions is now at least partially removed, exposing at least the edge regions of the multitude of optoelectronic components. Additionally, and optionally, portions of the dielectric material between the respective optoelectronic components can also be removed. Finally, according to the proposed principle, a conductive transparent layer is applied at least to the exposed edge sections of the multitude of optoelectronic components and to the dielectric material on the substrate, thus covering both. The conductive transparent layer forms an electrical contact with each of the multitude of optoelectronic components.

[0012] The present application therefore proposes the use of an optically transparent dielectric material in which the optoelectronic components arranged on the substrate are embedded, in order to additionally provide optical elements on an emission surface of the optoelectronic components. The corresponding processes are possible without dry etching, so that these steps can be integrated into existing processes and used at the wafer level.

[0013] In this respect, the size of the optoelectronic components can be less than 100 µm in length or diameter, corresponding to so-called micro-LEDs. Such micro-LEDs have a length of up to a few µm and are typically in the range of about 5 µm to about 50 µm. The optoelectronic components can be implemented as bulk or surface emitters without restriction. Bulk emitters are suitable, for example, when the dielectric material is filled with converter particles. Vertical and horizontal components, i.e., with their contact surfaces on opposite sides or on the same sides, are possible for this application.

[0014] In some cases, the dielectric material of the protrusion is at least partially removed, leaving a portion of the material behind to form a curved residual section on the surface of each of the multiple optoelectronic components. In other words, when parts of the dielectric material are removed, a portion of the protrusions remains above the top surface of the optoelectronic components, forming corresponding optical structures, such as lenses and the like.

[0015] The curvature and shape of the optical structures can be adjusted based on the amount of material deposited on each of the several optoelectronic components and the removal rate. Consequently, by varying the amount of material deposited on the top surface of the optoelectronic components and the curvature of the protrusions and projections during the removal process, the shape and form of the optical elements processed in this step can be adjusted.

[0016] In some other aspects, the step of at least partially removing the dielectric material includes removing a portion of the applied dielectric material located above the substrate. In these cases, removing portions of the dielectric material involves not only removing the dielectric material above the top surface of the optoelectronic components, but also material between the optoelectronic components. Consequently, the dielectric material adjacent to the edge of the optoelectronic components is flattened during this step, resulting in a height difference between the top surface of the dielectric material on the substrate and the exposed top surface of the edge region of the optoelectronic components.

[0017] According to aspects of the proposed principle, this height difference is kept smaller than the thickness of the transparent conductive layer deposited on the substrate, so that the transparent conductive layer rises above the exposed surface. Therefore, the distance u between a surface plane of the dielectric material on the substrate adjacent to the edge sections of the multiple optoelectronic components and a plane of the edge sections is smaller than the thickness of the deposited transparent conductive layer.

[0018] This approach ensures that during the deposition of the transparent conductive layer, a smooth and continuous transition is formed from the upper layer of the dielectric material between the optoelectronic components to the exposed surfaces of the respective optoelectronic components. Such a smooth transition is particularly advantageous with brittle materials like ITO, reducing the risk of breakage under thermal or mechanical stress.

[0019] In several other aspects, the thickness of the dielectric material on the substrate is therefore greater directly adjacent to the edge than the thickness at a greater distance. Consequently, during the dielectric material removal process, more material is removed between two adjacent optoelectronic components above the substrate than closer to the edge regions of the respective components. In some aspects, the dielectric material terminates at the edge regions of several optoelectronic components; that is, the top surface of the edge regions of the optoelectronic components is at the same level as the directly adjacent dielectric material, resulting in a continuous transition.

[0020] Some further aspects relate to the application of a dielectric material between the multiple optoelectronic components on the substrate, as well as to these components themselves.

[0021] In some aspects, the step of applying the dielectric material involves spinning it onto the substrate. Alternatively, the dielectric material can be applied, particularly to the top surface of the multiple optoelectronic components. Similarly, the dielectric material can be sprayed onto the substrate, specifically onto the top surface of the multiple optoelectronic components. In such cases, it is advantageous if the optoelectronic component has a relatively low viscosity, allowing the dielectric material to flow between the components and distribute itself evenly across the substrate's surface.

[0022] In some applications, the dielectric material is deposited in a low-viscosity form, such as a liquid, and subsequently heat-treated or irradiated to increase its viscosity. The dielectric material may contain fillers such as SiO2 or converter particles. In some cases, particularly when the first dielectric material forms optical lenses or other optical elements on its surface, its refractive index is approximately equal to, or slightly lower than, that of the conductive transparent layer. Possible materials for the first dielectric include, but are not limited to, silicones and siloxanes.

[0023] Pretreatment of the low-viscosity dielectric material transforms it into a more solid form suitable for further processing. In addition to heat treatment, the applied initial dielectric material can also be irradiated with UV light, with either heat treatment or UV irradiation adjusting the material's strength. This allows the dielectric material to be further modified or processed in subsequent steps, particularly facilitating the shaping of optical elements on the top surface of optoelectronic components made from the applied initial dielectric material.

[0024] The step of at least partially removing the first dielectric material can include plasma etching. Additionally or alternatively, chemical etching or mechanical removal processes can be performed. For example, mechanical removal processes are possible to create a substantially uniform and smooth surface of the dielectric material, fully exposing the surface of the numerous optoelectronic components.

[0025] Some further aspects relate to additional steps for producing the arrangement according to the proposed principle.

[0026] For example, the process can also include the step of depositing a second photostructurable dielectric material onto the conductive transparent layer. This second photostructurable dielectric material can, for instance, be spin-deposited onto the conductive transparent layer to obtain a smooth and essentially flat surface. In a subsequent step, the second photostructurable dielectric material is structured to form light-shaping or other optical elements over the top surface of the multitude of optoelectronic components. These optical elements can include lenses, collimators, output coupling structures, and the like.

[0027] It is possible that the second photostructurable dielectric material includes conversion particles to convert the light emitted from the top of the optoelectronic components.

[0028] To structure the second photostructurable dielectric material, a photoresist layer can be applied to it. The photoresist itself can then be structured, and the portion of the second photostructurable dielectric material not protected by the structured photoresist can be removed. In some cases, the photostructurable dielectric material is preheated or treated with light to shape the optical element above the surface. This allows for the creation of microlenses in a desired shape after the portions of the second photostructurable dielectric material not protected by the structured photoresist have been removed.

[0029] In this respect, the structuring of the photoresist may involve removing the photoresist and removing unilluminated parts, or vice versa, before removing the material of the second photostructurable dielectric material protected by the structured photoresist.

[0030] The second dielectric material can include BCB or spin-on-glass (SOG) materials suitable for this purpose. For example, siloxanes or silicon-based materials can be used for the first and / or second dielectric material. In some cases, flat material can be incorporated into the first and second dielectric materials to achieve different physical and chemical properties. In some cases, TiO₂ is incorporated into the first dielectric material to increase the reflectivity of the support structure.

[0031] Several other aspects concern an arrangement comprising a carrier with a multitude of contact lines. A multitude of optoelectronic components are arranged on the carrier such that a first contact area of ​​each of the multitude of optoelectronic components connects to a respective contact line.

[0032] Each of the multiple optoelectronic components also includes an emission surface that is essentially opposite the contact lines. Therefore, in some cases, the optoelectronic components can be arranged as vertical components where the respective contact surfaces are located on opposite sides. In other embodiments, the optoelectronic components can be implemented as horizontal microLEDs where the respective contact surfaces are located on the same side.

[0033] The arrangement according to the proposed principle also includes a first dielectric material positioned between the multitude of optoelectronic components on the substrate. This first dielectric material extends onto the substrate in such a way that it is connected to the side walls of the respective optoelectronic components. In other words, the multitude of optoelectronic components is embedded within the first dielectric material.

[0034] A conductive transparent layer is arranged on the first dielectric material and at least partially on edge portions of the top surface of each plurality of optoelectronic components, connecting their second contact area. In some cases, the conductive transparent layer extends over both the first dielectric material and the top surface of each of the plurality of optoelectronic components. Consequently, the conductive transparent layer can cover the entire arrangement. A light-shaping optical element is also provided on the top surface of each of the plurality of optoelectronic components according to the proposed arrangement. The conductive transparent layer covers one of substantially two opposing surfaces of the light-shaping optical element.

[0035] In some aspects, the conductive transparent layer extends from the edge region across the light-shaping optical element, thereby covering the underlying light-shaping optical element. The light-shaping optical element may have a curvature that forms a lens on the top surface of each of the multiple optoelectronic components.

[0036] In some other aspects, the light-shaping element can comprise a second dielectric material that may differ from the first. In this respect, the conductive transparent layer can, in some cases, be positioned between the light-shaping structure and the surface of the optoelectronic components. Similar to the previous embodiments, the light-shaping element can be configured as a lens, collimator, or any other optical component.

[0037] Several aspects relate to the arrangement of the conductive transparent layer on the substrate, as well as the height of the top surface of the optoelectronic components. In some aspects, the conductive transparent layer has a thickness greater than the distance between the top surface of the first dielectric material on the substrate, adjacent to the edge regions of the multiple optoelectronic components, and a plane of these regions. Consequently, the conductive transparent layer forms a smooth and continuous transition from a point above the substrate to the top surface of the optoelectronic components. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Further aspects and embodiments according to the proposed principle become clear with regard to the various embodiments and examples, which are described in detail in connection with the accompanying drawings, in which Fig. 1 shows an embodiment of an optical arrangement with a µLED on a substrate; Fig. 2A and Fig. 2B shows two optoelectronic components with optical elements arranged on their upper surfaces; Fig. 3 shows a first embodiment of an optical arrangement according to the proposed principle; Fig. 4 shows a second embodiment of an optical arrangement according to the proposed principle; Fig. 5A and Fig. 5B Illustrate two initial process steps for the manufacture of an optical arrangement according to some aspects of the proposed principle; Fig. 6A and Fig. Figure 6B shows two further process steps for the production of an optical arrangement according to some aspects of the proposed principle; Fig. 7A and Fig. Figure 7E shows several process steps for manufacturing another optical arrangement according to some aspects of the proposed principle. DETAILED DESCRIPTION

[0039] The following embodiments and examples reveal various aspects and their combinations according to the proposed principle. The embodiments and examples are not always to scale. Likewise, various elements may be enlarged or reduced to highlight individual aspects. It is understood that the individual aspects of the embodiments and examples shown in the figures can readily be combined without contradicting the principle of the invention. Some aspects have a regular structure or shape. It should be noted that in practice, minor differences and deviations from the ideal form may occur without contradicting the inventive concept.

[0040] Furthermore, the individual figures and aspects are not necessarily depicted in the correct size, nor do the proportions between the individual elements have to be essentially correct. Some aspects are emphasized by magnification. However, terms such as "above," "over," "below," "under," "larger," "smaller," and the like are correctly represented in relation to the elements within the figures. Thus, it is possible to deduce such relationships between the elements from the figures.

[0041] Fig. Figure 1 shows an embodiment of a conventional optoelectronic arrangement 1, which is subsequently modified with aspects of the proposed principle.

[0042] The optoelectronic arrangement comprises a support substrate 30 on which a plurality of optoelectronic components 1 are arranged.

[0043] The optoelectronic components 10 each comprise a semiconductor body 11 with a top surface 12 and a bottom surface 13. The top surface 12 also includes a main exit surface. The bottom surface 13 further comprises a contact area for contacting the optoelectronic component 1 with a contact pad 21 of the support substrate 30.

[0044] The optoelectronic component 1 is implemented here as a microLED, specifically as a surface emitter and a horizontal microLED. The term "surface emitter" means that the main light emission occurs through the top surface 12. In contrast, a so-called "volume emitter" emits light across its entire volume. The term "vertical component" or "vertical microLED" refers to a component that includes two contact surfaces on opposite sides, for example, a contact surface on the bottom surface 13 and a contact surface on the top surface 12, where one of the contact surfaces can also form an emission surface. A horizontal microLED includes contact surfaces on the same side of its body.

[0045] Although the proposed principle and embodiments mainly illustrate vertical surface emitter components, the proposed principle is neither limited to surface or volume emitters as such, nor is it limited to horizontal or vertical components as previously defined.

[0046] The substrate 30 comprises several different layers, 37, 32, and 36. Layer 32 forms an intermediate layer located between the upper layer 36 and the lower layer 37. The intermediate layer 32 includes a contact surface 33 with several conductive contact lines, which are connected via a via 31 to the upper layer 36 of the substrate 30. The via 31 connects the contact surface 21 on the surface of the upper layer 36, on which the optoelectronic component 1 or µLED is located. In the present embodiment, the µLED 1 is configured as a horizontal surface emitter. Therefore, the upper layer 36 includes a second contact line 20 that connects to the other contact of the µLED.

[0047] In the present embodiment, the optoelectronic components are designed as microLEDs with a diameter of approximately several tens of micrometers, for example, between 10 µm and 50 µm. To position the microLEDs correctly and without defects on the substrate, the contact area 21 can be larger than the respective contact area or even the underside 13 of the respective microLED. This ensures correct positioning and electrical contact of the microLED on the substrate and its contact area 21, even if the microLED is placed on the substrate 30 with certain tolerances.

[0048] The Fig. 2A and Fig. Figure 2B shows two embodiments of an optoelectronic device and an optoelectronic arrangement 1 according to the proposed principle. The arrangement 1 comprises an optoelectronic component 10 mounted on a respective support substrate, which in the respective Fig. 2A and Fig. Figure 2B is not shown. The optoelectronic component 10 is designed as a microLED with a semiconductor body 11 and a main surface 12. The microLEDs, configured as vertical components, include a contact area 12a arranged as a ring-shaped structure on the top surface 12 and extending around a central area of ​​the top surface. However, the contact area 12a of the vertical component can also encompass the entire top surface.

[0049] The optoelectronic component in Fig. 2A comprises a metallic contact 38 at the circumferential edges 12a, which form part of the contact surface of the optoelectronic component. The metallic contact 38 therefore also includes a circumferential structure, wherein the central part of the top surface 12 remains uncovered but, as can be seen in the sectional view of the embodiment, is slightly recessed. A transparent dielectric material 35 is arranged in the recess and the central part above the main exit surface. The transparent dielectric material 35 comprises a circular hemisphere or an oval shape that forms a microlens on a surface of the optoelectronic component. To contact the optoelectronic component, a transparent conductive layer 40 is applied to the metallic contact 38 as well as to the lens structure 35. The conductive transparent layer 40 comprises, for example, ITO.

[0050] In contrast, the conductive transparent layer 41 extends into Fig. 2B across the entire microlens formed by the dielectric transparent material 35 down to the contact area 12a of the top surface 12. This structure therefore leads to a different angle between the section of the conductive transparent layer 40 on the dielectric material 35 and the contact area 12a or 38, as shown in the Fig. 2A and Fig. 2B is shown. The angle between the conductive transparent layers 40 and 41 is slightly different, with the angle in the case of Fig. 2A becomes larger due to the additional material 38. This steeper angle, as in Fig. 2A is particularly advantageous for ITO and other brittle materials. A larger angle results in a smoother and more continuous transition during the deposition of the conductive transparent layer onto the structure and reduces the risk of increased resistance in the transition region due to fracture between sections 41 and 40.

[0051] In this respect, a steeper angle can also be achieved by changing the surface tension of the dielectric material deposited on the surface of the optoelectronic component. The angle depends on the surface properties between the dielectric material 35 and the surface of the semiconductor body 11. The angle between them can be adjusted by changing the viscosity of the dielectric material during deposition, its composition (e.g., by adding solvents, etc.), preheating measures, and other process parameters. A steeper angle promotes a smoother and crackle-free transition of the conductive transparent material.

[0052] Fig. Figure 3 shows another embodiment of an optoelectronic arrangement 1 according to some aspects of the proposed principle.

[0053] The arrangement comprises a carrier 30 with an upper support layer 36, as shown, on which a plurality of µLEDs and optoelectronic components 10 are arranged. Each of the µLEDs is configured as a vertical µLED with a lower contact area 13 that is directly arranged and positioned on a respective contact area 21 of the support layer 36. The plurality of µLEDs 10 is embedded in a transparent dielectric material 34. The dielectric material 34 extends from the top surface of the support layer 36 near the upper edge regions of the optoelectronic components. However, the dielectric material 34 between the plurality of optoelectronic components is slightly recessed and does not extend over the top surface of the components.

[0054] A conductive transparent contact layer of ITO is arranged on the top surface of the dielectric material in regions between the plurality of optoelectronic components. The conductive transparent contact layer extends further onto the optoelectronic components, forming regions 41 and 40 respectively. In particular, region 42 is deposited on the dielectric material 34 between the plurality of optoelectronic components. Region 40 extends over the dielectric transparent material 35, which is applied to the main exit surface. Regions 41 are located near the circumferential edges of each of the optoelectronic components and comprise a transition or step-like structure, as shown in Fig. 3 shown to connect section 42 of the conductive transparent layer to section 40 of the conductive layer and contact area 12a of the optoelectronic components.

[0055] As shown here, the thickness of the conductive transparent layer is chosen such that the distance from the top surface of the dielectric material 34 between the optoelectronic components and the top surface, which is the contact area 12a of the optoelectronic components, is equal to or less than the thickness of the conductive electrical layer applied to the material 34. This allows a smooth transition from the brittle material to a contact area 12a and the contact lenses 35.

[0056] The material of the contact lenses 35 is the same as the dielectric material 34 between the optoelectronic components and is processed and manufactured using the same steps as described in detail below. The size and curvature of the microlenses 35 are determined by the manufacturing parameters and adjusted so that the angle between the conductive layer 40 on the top surface of the microlenses and the section 41 is as large as possible to avoid fractures during the deposition of the conductive layer material or thermal stresses during subsequent operation of the device.

[0057] Fig. Figure 4 illustrates another embodiment of the proposed principle. In this embodiment, the dielectric material 35 is completely removed from the top surface of the optoelectronic components 10. A conductive transparent layer is applied to the top surface of each of the optoelectronic components 10, as well as to the intervening dielectric material 34, thereby contacting the contact areas 12a of each component. A dielectric transparent layer 40 with a flat surface, acting as an optical lens, is formed on the top surface 12 of each of the optoelectronic components. This structure is formed separately after the application and formation of the conductive transparent layer 40.

[0058] The two embodiments shown herein in Fig. 3 and Fig. Four are processed simultaneously, enabling wafer-wide fabrication and formation of optical structures on the top surfaces of optoelectronic components and microLEDs. Fig. 5A and Fig. Figure 5B illustrates some process steps for a method for manufacturing an optical arrangement according to the proposed principle.

[0059] In Fig. Figure 5A shows a carrier 30, of which only a single layer 36 is shown. The carrier 30 comprises a plurality of contact lines 21 on its respective top surface. The contact lines 21 are connected through the top layer 36 of the carrier 30 via a plurality of vias 31. The area of ​​the contact lines 21 is designed to be larger than the respective base contacts 13 of a plurality of optoelectronic components mounted on it. This allows the optoelectronic components to be easily repositioned when mounted on the carrier 30 without losing the electrical contact between the base contact area 13 and the contact lines 21. Fig. Figure 5A shows the result after applying the several optoelectronic components 10 in the form of vertical µLEDs ( ) to the contact lines 21. Each of the optoelectronic components includes a top surface 12, which also forms the main emission surface of the µLED.

[0060] In a subsequent step, a dielectric material 34 is applied to the surface of the support 30 and the components 10 using a centrifugal technique. The dielectric material 34 has a viscosity that allows it to flow between the spaces between the optoelectronic components on the support. Furthermore, the amount of material 34 applied to the support 30 and the optoelectronic component is adjusted so that the top surface of the dielectric material 34 extends beyond the top surface 12 of the optoelectronic components. Thus, the optoelectronic components are completely embedded in the dielectric material.

[0061] Due to the obstacles on the substrate 30, namely the optoelectronic components 10, the dielectric material 34 applied to the substrate forms small protrusions and projections over the optoelectronic components or the µLEDs 10. These protrusions 34 are in Fig. 5B is shown and essentially follows the positions of the optoelectronic components.

[0062] As seen in the section view of Fig. As shown in Figure 5B, the protrusions and elevations 34a are smooth and extend continuously along the surface plane, so that no sharp steps are formed on the surface of the dielectric material 34a. Rather, the curvature of the protrusion 34 depends to some extent on the surface tension of the optoelectronic components and the dielectric material 34a, its deposition viscosity, the total amount of material deposited, and other adjustable parameters. Consequently, the curvature of the protrusions 34a can be adjusted to some extent and, for example, increased by using slightly less dielectric material.

[0063] The dielectric material 34a can now be pretreated to ensure a certain stability for further production.

[0064] In some subsequent steps, which are described in the Fig. 6A and Fig. As shown in Figure 6B, the dielectric material 34 is now processed and partially removed in the areas between the optoelectronic components. For this purpose, a plasma etching process or a similar anisotropic process is carried out. The plasma etching process removes portions of the dielectric material 34, starting from its top surface. However, due to the material located on the top surface of the optoelectronic components 10, the plasma etching process causes the dielectric material 34 to be removed between the optoelectronic components as well as around the edge regions of the respective optoelectronic components, leaving a portion of the dielectric material in the center. These portions of the dielectric material remaining on the top surface form microlenses 35 on the optoelectronic components, as shown in Figure 6B. Fig. 6A is shown.

[0065] Due to the plasma etching process, the dielectric material 34 is also removed between the optoelectronic components, resulting in a step-like structure between the upper edges of the optoelectronic components 10 and the surface of the directly adjacent dielectric material 34. In other words, the surface of the dielectric material 34 between the optoelectronic components lies slightly below the surface of the optoelectronic components themselves.

[0066] In a subsequent step, a conductive transparent layer 40, 41 and 42 is applied to the top surface of the material 34, the remaining material 35, and the circumferential edge regions of the several optoelectronic components 10. The result is in Fig. Figure 6B illustrates this. The thickness of the applied material is adjusted and specified such that the regions 42 on the top surface of the dielectric material 34 extend over the surface of the optoelectronic components 10. Consequently, several circumferential transition regions 41 of the transparent conductive layer are formed, which contact the contact regions 12a of the optoelectronic components. Furthermore, the conductive transparent material extends over the dielectric material 35 and forms the top sections 40 on the optical lenses. Depending on the refractive index, the optical lenses and the conductive transparent layer material 40 can form specific optical functions, such as collimating or dispersive lenses.

[0067] The Fig. Figures 7A to 7E illustrate another embodiment of the proposed principle. In this embodiment, the dielectric material 34 comprises conversion particles or other filler particles to increase or modify the reflectivity or wavelength of the light emitted by the optoelectronic components. Accordingly, in some cases, the optoelectronic components 10 are now implemented as volume emitters that emit not only from their main surface 12 but also laterally. In some aspects, they are primarily surface emitters. Additionally, the contact lines 21 on the substrate 36 are connected to a conductive metal structure 20, which forms supply and control lines for the optoelectronic components.

[0068] After the multitude of optoelectronic components are arranged on the carrier 30 and these optoelectronic components are placed in the Fig. In the dielectric material 34 shown in 7A, which is embedded, the first dielectric material 34 is at least partially removed from the surface 12 of the optoelectronic components, leaving an exposed top surface. In an embodiment of Fig. 6B In the following step, material of a transparent conductive contact layer is applied to the top of the dielectric material 34 and the optoelectronic components 10.

[0069] Similar to the previous embodiment, the thickness of the conductive layer material is adjusted to ensure a smooth transition across the entire circumference of the respective optoelectronic components. The layer then forms a continuous transition from region 42 to region 40. This transition of the conductive layer material ensures that, particularly with brittle materials such as ITO, no breaks occur that could lead to high, undesirable contact resistance or an unreliable electrical contact.

[0070] In a subsequent step in Fig. In step 7B, a second dielectric material 50 is applied to the transparent conductive layer 40, 42, and 41. The second dielectric material 50 can be the same as the first dielectric material 34, but it can also comprise materials other than the first dielectric material. Furthermore, the second dielectric material 50 is a photostructurable material, allowing the layer to be structured by photolithographic means.

[0071] For this purpose, a photoresist layer is applied to the surface of the second dielectric material 50 and subsequently structured, for example using a photomask, to form areas 60 above the main surface 12 of the underlying optoelectronic components, as shown in Fig. 7C is shown. The second dielectric material is illuminated to form areas of illuminated material, as shown in Fig. 7D representation. In a subsequent step, the material in these areas 52 is removed and the photoresist layer 60 is peeled off to expose optical elements 41 on the top side of the optoelectronic components, resulting in the final structure of Fig. 7E leads. The second dielectric material can be further processed, cured, or healed to form a variety of stable optical elements on the µLEDs.

[0072] In an alternative embodiment, a photomask or a shadow mask is aligned over the deposited second dielectric material 50. The mask can then be directly illuminated, leading to the development of specific areas of the second dielectric material. Subsequently, the area no longer needed can be removed.

[0073] The proposed principle enables the simultaneous fabrication of a variety of optoelectronic components, including the structuring and shaping of optical elements. The proposed step can be easily integrated into currently available processes, leading to cost-effective mass production of microLEDs with top-side optical elements. Although the present embodiments are shown with some specific substrates, including power supply and control strips, the proposed principle is not limited to these and can also be used for temporary substrates requiring a subsequent transfer process. REFERENCE MARK LIST 1 optoelectronic arrangement 10 optoelectronic component 11 Semiconductor bodies 12 upper surface 12a Contact area 13 lower contact 20 Contact Line 21 Contact area 30 carriers 31 Through-hole plating 33 Contact area 32 Intermediate support position 33 Contact level 34 Dielectric layer 35 Dielectric material, optical element 35a Dielectric material, optical element 36 upper support layer 37 Carrier layer 38 metal contacts 40 conductive transparent layer 41 Conductive transparent layer at the edge areas 42 conductive transparent layers

Claims

[1] Method for producing an arrangement comprising: - Providing a plurality of optoelectronic components, in particular µLEDs, arranged on a substrate, wherein each optoelectronic component of the plurality of optoelectronic components comprises a contact area electrically connected to a contact line on the substrate and an emission surface substantially opposite the contact area; - Applying a dielectric material to the substrate and the plurality of optoelectronic components, such that the dielectric material forms a surface with a plurality of continuous protrusions, each protrusion being located above one of the respective optoelectronic components; - at least partial removal of the dielectric material of the protrusions, so that at least the edge areas of the several optoelectronic components are exposed; - Applying a conductive transparent layer at least to the exposed edge sections of the multiple optoelectronic components and the dielectric material on the substrate to establish electrical contact with each of the multiple optoelectronic components. [2] Method according to claim 1, wherein the at least partial removal of the dielectric material of the projections comprises leaving a curved residual section of the projection on the surface of each of the multiple optoelectronic components forming respective lenses, wherein the curvature is optionally based on the material arranged on each of the multiple optoelectronic components and the ablation rate. [3] Method according to one of the preceding claims, wherein the step of at least partially removing the dielectric material comprises removing a part of the applied dielectric material from the support, such that a distance between a surface plane of the dielectric material on the support next to the edge sections of the plurality of optoelectronic components and a plane of the edge sections is less than a thickness of the deposited conductive transparent layer. [4] Method according to one of the preceding claims, wherein the thickness of the dielectric material on the support directly next to the edge is greater than the thickness at a greater distance, wherein in particular the dielectric material closes at edge sections of the plurality of optoelectronic components. [5] Method according to any one of the preceding claims, wherein the step of applying a dielectric material comprises at least one of the following: - Application of the dielectric material - apply the dielectric material, in particular, to the top surface of the multitude of optoelectronic components; - spray the dielectric material, especially onto the top surface of the multitude of optoelectronic components - Heat treatment of the applied dielectric material, in particular after the step of at least partial removal of the material; - Irradiation of the applied dielectric material, especially with UV light. [6] Method according to any of the preceding claims, wherein the step comprises at least partially removing the dielectric material: - Plasma etching of the material; - the chemical etching of the material; - mechanical removal of the material. [7] A method according to any of the foregoing claims, further comprising: - Application of a second photostructurable dielectric material, in particular by spinning it onto the conductive transparent layer; - Structuring the second photostructurable dielectric material to form light-shaping structures over the top of the multitude of optoelectronic components. [8] The method of claim 7, further comprising: - Providing and aligning a shadow mask or photomask over the second photostructable dielectric material after the application of the second photostructable dielectric material. [9] Method according to claim 7, wherein the structuring step comprises at least one of the following steps: - Application of a photoresist to the second photostructurable dielectric material; - Structuring the photoresist; - Removal of material of the second photostructurable dielectric material that is not protected by the structured photoresist. [10] Method according to claims 7 to 9, wherein the structuring of the second photostructurable dielectric material comprises the step - Preheating or light-treating the second photostructurable dielectric material to shape the structures above the top surface. [11] Method according to claims 7 to 10, wherein the second dielectric material comprises BCB and / or a spin-on glass material. [12] arrangement, encompassing - a carrier with a multitude of contact lines; - a plurality of optoelectronic components arranged on the carrier such that a first contact area of ​​each of the plurality of optoelectronic components connects a respective contact line, wherein each of the plurality of optoelectronic components comprises an emission surface that is substantially opposite the contact line; - a first dielectric material that is arranged between the multitude of optoelectronic components on the substrate and connected to its wall; - a conductive transparent layer that is arranged on the first dielectric material and at least partially on edge sections of a top surface of each of the several optoelectronic components and connects a second contact area of ​​the same; - a light-shaping optical structure on the top side of each of the multiple optoelectronic components, wherein the conductive transparent layer covers one of substantially two opposing surfaces of the same. [13] Arrangement according to claim 12, wherein the conductive transparent layer extends from the edge region over the light-shaping optical structure and thereby covers the light-shaping optical structure; or wherein the conductive transparent layer is arranged between the light-shaping optical structure and the top surface of each of the multiple optoelectronic components. [14] Arrangement according to one of claims 12 to 13, wherein - the light-shaping structure is designed as a lens that includes the first dielectric material; or - the light-shaping structure comprises a second dielectric material that differs in particular from the first dielectric material. [15] Arrangement according to one of claims 12 to 14, wherein the conductive transparent layer has a thickness greater than a distance between a top surface plane of the first dielectric on the support adjacent to the edge regions of the multiple optoelectronic components and a plane of the edge regions.

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