Method for processing device having [mu] LEDs and device

Abstract

The invention relates to a method for processing a device having a plurality of [mu] LEDs, comprising the steps of providing a plurality of vertical [mu] LEDs on a carrier substrate, the [mu] LEDs having a contact area on a top surface opposite the carrier substrate, and embedding the plurality of vertical [mu] LEDs in a photoactive material, the photoactive material covers a space between adjacent [mu] LEDs of the plurality of optoelectronic components and a top surface of the plurality of optoelectronic components. A portion of the photoactive material over the top surface at least partially including the contact region is irradiated and developed, thereby removing the portion of the photoactive material such that a portion of the top surface at least partially including the contact region is exposed. A conductive transparent layer is deposited over the remaining photoactive material and the exposed portion of the top surface to electrically contact the contact area.

Description

[0001] The present invention relates to a method for processing optoelectronic components, particularly μLEDs, and an optoelectronic device comprising a plurality of μLEDs. Background Technology

[0002] Testing a number of μLEDs at a time and at various stages of their manufacturing process is necessary to avoid large batches of damaged components and improve yield during production. While some testing can be performed directly at the wafer level, dedicated test equipment, known as test carriers, is also typically provided.

[0003] To fabricate such a test carrier, multiple μLEDs are removed from a production wafer and placed on a corresponding carrier test substrate. The multiple μLEDs are then further processed to realize the test carrier, which is subsequently used for various electrical and optical tests. However, as a device with multiple μLEDs, the fabrication and realization of such a test carrier is prone to errors.

[0004] Specifically, the process of spin-coating a dielectric material, such as SOG (spin-on glass), onto the carrier and the corresponding μLED creates steps around the μLED. Due to these steps around the μLED, any conductive layer (such as ITO) deposited and sputtered onto the SOG material tends to crack. In particular, subsequent stress testing during the testing process, under conditions where the device is subjected to real-life scenarios, can lead to fractures in the conductive layer material. These problems are not necessarily limited to test carriers but typically involve devices with multiple μLEDs, such as displays, light projectors, etc.

[0005] In conventional techniques, the SOG material on the top surface is removed to expose the surface of the μLED through a dry etching process. However, due to various tolerances such as the thickness of the μLED, slight tilt when placing the μLED on the carrier substrate, solder thickness, and other factors, the top surfaces of multiple μLEDs are often uneven. Therefore, the etching process that removes the SOG material to expose all surfaces will etch the SOG material between the μLEDs, making it difficult to perform a defined and reproducible process for depositing conductive material for testing and other purposes.

[0006] Therefore, it is desirable to improve devices with multiple μLEDs to produce error-resistant structures with higher reproducibility. Summary of the Invention

[0007] This and other objectives are addressed by the subject matter of the independent claim. Features and other aspects of the proposed principle are outlined in the dependent claims.

[0008] The inventors propose an improvement to the process steps for producing and manufacturing devices with multiple μLEDs by embedding multiple μLEDs in a planarizing material (which is photoactive), thus allowing the device to be easily structured without a dry etching process. Therefore, regions of such photoactive material can be developed using a photomask layer or a direct laser imaging device, thereby subsequently exposing the contact surfaces for contacting the multiple μLEDs.

[0009] The newly proposed step eliminates the need for reverse etching or mechanical polishing to remove the spin-coated glass material, instead requiring only a simpler removal of a portion of the photoactive material. The photoactive polymer material remains on the device, allowing the optoelectronic components and μLEDs to be embedded. This reduces the risk of damaging the corresponding μLEDs during processing due to the aforementioned tolerances and enables improved process control. Furthermore, several steps used in conventional processing techniques can be skipped, resulting in a faster manufacturing process, which is particularly suitable for devices used for testing purposes.

[0010] Several aspects relate to methods for processing devices having multiple optoelectronic components, particularly μLEDs. Such methods include the step of providing multiple vertical components, particularly vertical μLEDs, on a carrier substrate. Each vertical optoelectronic component includes a contact region on a top surface opposite the carrier substrate.

[0011] In this regard, the term "vertical optoelectronic component" refers to an optoelectronic component comprising two contact regions on opposite sides. In the proposed principle, such a vertical optoelectronic component is arranged on a carrier substrate and connected to a corresponding contact region on the carrier substrate with its respective bottom contact region. Opposite contact regions are arranged on the top surface of the optoelectronic component.

[0012] The term "μLED" refers to an optoelectronic component, which can be a bulk emitter or a surface emitter, and includes lengths or widths of less than 70 μm and as small as a few micrometers. Typical μLEDs include lengths of approximately 4 μm to 20 μm (e.g., 15 μm, 10 μm, or 8 μm). Due to their size, these μLEDs are typically implemented as vertical optoelectronic components.

[0013] Based on the proposed principle, multiple vertical optoelectronic components are embedded in a photoactive material. The photoactive material fills the spaces between adjacent vertical optoelectronic components and the top surfaces of such components. The material forms a generally flat surface on the carrier substrate and the components, while the optoelectronic components may produce small, hill-shaped, curved protrusions on the plane of the photoactive material. Therefore, the photoactive material may not be completely flat, but rather slightly uneven, with roughness typically less than 1 μm or less than 0.5 μm, and of course less than the height of the vertical optoelectronic components.

[0014] The portion of the photoactive material located above the top surface of the contact area that at least partially contains the corresponding optoelectronic component is then irradiated and thus developed. The developed portion can then be removed, leaving the undeveloped portion. Alternatively, the steps can be reversed, i.e., for example, the photoactive material not located above the top surface of the contact area that at least partially contains the corresponding optoelectronic component is irradiated and developed, and then the undeveloped portion above the top surface is removed.

[0015] In both cases, the subsequent removal will expose at least a portion of the top surface containing the contact area.

[0016] Then, a conductive transparent layer is provided on the remaining photoactive material and the exposed portion of the top surface of the vertical optoelectronic component to electrically contact the contact area of ​​the corresponding optoelectronic component.

[0017] As noted, the proposed principle protects optoelectronic components from potential damage by embedding them in a photoactive material, while the corresponding top surface can be exposed and subsequently contacted without additional etching steps. Furthermore, it reduces or completely eliminates potential edges between the optoelectronic components and the spin-coated glass material due to the varying etching rates used in conventional techniques. However, it retains the advantages of maintaining very precise positioning of photomask layers or direct laser imaging processing.

[0018] In some other aspects, a structured mask layer is provided on the photoactive material such that a portion of the top surface, at least partially containing the contact region, is exposed. In this respect, the structured mask layer may include multiple transparent elements, such as holes or lenses. These transparent elements are located above the portion of the top surface that at least partially contains the contact region. The photoactive material above these portions is then irradiated to be removed in a later, more simplified cleaning step without the need for etching the photoactive material.

[0019] A direct laser imaging device can be used instead of a structured photomask layer. Here, the positions of the top surface of multiple optoelectronic components on a carrier substrate are first obtained. After obtaining such positions, a portion of the photoactive material above the top surface, which at least partially comprises the contact area of ​​the vertical optoelectronic components, is illuminated using a direct laser imaging device. The advantage of this particular process is that the positions of the respective top surfaces of these components can be obtained after the multiple optoelectronic components have been placed on the carrier substrate, but before these components are embedded in the photoactive material. Therefore, tolerances or tilts during the positioning or arrangement process of the multiple optoelectronic components on the carrier substrate can be compensated for.

[0020] In some other aspects, the step of developing the photoactive material includes the step of removing the irradiated portion, such that the unirradiated portion of the photoactive layer remains on the carrier substrate. However, this particular step can also be reversed, such that the step of developing the protective material includes the step of removing the unirradiated portion, such that the irradiated portion of the photoactive layer remains on the carrier substrate.

[0021] The latter step is clearly useful when the carrier substrate, encompassing multiple optoelectronic components, is further processed to realize a display or any other device, and the photoactive material remains on the carrier substrate during normal operation of such a device. In such cases, protecting the photoactive material from oxygen or other degrading substances may be useful.

[0022] Some additional aspects involve the step of providing a structured mask layer. Such a step may include providing a structured mask layer comprising multiple transparent portions such as holes, lenses, etc. The structured mask layer is disposed over a photoactive layer material such that each or all of the multiple transparent portions are positioned over a corresponding portion of a top surface that at least partially includes the contact area. However, the transparent portions in the structured mask layer are slightly smaller than the area of ​​the top surface. Therefore, during subsequent irradiation steps, the photoactive layer on the top surface is not fully irradiated, but only a portion of it is irradiated, resulting in the material at the peripheral edges remaining undeveloped.

[0023] Therefore, after the step of removing the developed portion, a small portion of photoactive material can remain on the outer edge of the top surface of the corresponding optoelectronic component. In this regard, the multiple transparent portions can include circular or rectangular shapes. Alternatively, the multiple transparent portions can also be elliptical or polygonal. The recesses formed thereon in the exposed contact area after removing the irradiated photoactive material can include the same shape.

[0024] Some steps involve embedding multiple vertical optoelectronic components into a photoactive material. In some aspects, the photoactive material can be sputtered onto a carrier substrate and the optoelectronic components, thereby covering the optoelectronic components and their top surfaces. Alternatively, the photoactive material can be deposited onto the carrier substrate and the multiple optoelectronic components by spin coating.

[0025] As an alternative, the photoactive material can be disposed onto a carrier substrate, and particularly between adjacent optoelectronic components in a plurality of vertical optoelectronic components. In some cases, a portion of the photoactive material can also be disposed onto the top surface of some of the plurality of vertical optoelectronic components. In yet another alternative, the photoactive material can be sprayed onto the carrier substrate, and particularly between adjacent optoelectronic components. The photoactive material can also be sprayed onto some or all of the top surfaces of the plurality of vertical optoelectronic components.

[0026] In this regard, the development step may include etching the irradiated or developed portions of the photoactive material. Alternatively, the unirradiated portions of the photoactive material (corresponding to the undeveloped portions) may be etched. However, such an etching process differs from the etching process for spin-coating glass materials in conventional techniques and is similar to simply removing the photoactive material using a solvent suitable for material removal. These solvents are typically non-abrasive and do not interfere with or damage the optoelectronic components or the deactivated portions of the photoactive material.

[0027] Heat treatment can be performed after the photoactive material is set, or before or after the development step. For example, after development and removal, the remaining photoactive material can be baked to further improve stability and prevent delamination in subsequent steps. In this regard, the coefficient of thermal expansion (CTE) is selected such that, for the temperature range used during operation of the apparatus, the CTE is similar to that of the surrounding material.

[0028] The conductive transparent layer may include ITO and may be sputtered onto the top surface of the remaining photoactive material and optoelectronic components, such that the conductive transparent layer extends along the edge between the exposed contact area of ​​the photoactive material and the top surface. In this respect, the thickness of the conductive transparent layer, or simply the amount of sputtered material, is sufficiently large such that the thickness on the exposed contact area of ​​the top surface is smoothly connected to the conductive transparent material on the photoactive layer surrounding the exposed contact area.

[0029] On the other hand, the invention relates to a device having multiple optoelectronic components. The device includes a carrier substrate comprising multiple contact leads. Multiple vertical optoelectronic components, and particularly μLEDs, are arranged on the carrier substrate, and particularly on the multiple contact leads. The device is arranged such that a first contact region of each of the multiple vertical optoelectronic components is connected to a corresponding contact lead on the carrier substrate. Furthermore, each of the multiple vertical optoelectronic components includes a second contact region opposite to the first contact region.

[0030] Based on the proposed principle, a non-conductive, deactivated photoactive material is disposed on a carrier substrate, and multiple vertical optoelectronic components are embedded within the deactivated photoactive material. A portion of the deactivated photoactive material extends onto the top surface of the respective plurality of vertical optoelectronic components, exposing at least a portion of the second contact region. For example, the portion of the top surface covered by the deactivated photoactive material may include the peripheral edge portion of the plurality of vertical optoelectronic components. A conductive transparent layer covers the deactivated photoactive material and the exposed contact regions of the plurality of vertical optoelectronic components, thereby providing electrical contact.

[0031] Because the thickness of the deactivated photoactive material extending to the top surface is significantly smaller, the step between the exposed contact area and the photoactive material is thin enough to allow the transparent conductive layer to form a stable, well-defined, and controllable contact. More specifically, such a step, unlike in conventional techniques, is not arranged along the sidewalls of the optoelectronic component, avoiding the risk of fracture or breakage of the conductive transparent material due to thermal stress. In some cases, the thickness of such a step can range from a few nm to approximately 500 nm, and in any case, less than 1 μm. Therefore, in some cases, the transparent conductive material can include a thickness greater than that of the step of photoactive material extending horizontally above the top surface.

[0032] In some respects, the exposed area of ​​the top surface may include circular, rectangular, polygonal, or elliptical shapes.

[0033] Some aspects relate to the shape and structure of a portion of deactivated photoactive material extending above the top surface of a vertical optoelectronic component. As already mentioned, the deactivated photoactive material extends along the peripheral edge of the respective optoelectronic component on the top surface. In some aspects, the surface of the deactivated photoactive material may include curvature such that the thickness of the photoactive material partially increases toward the exposed contact area. Thus, the thickness of the photoactive material may become larger toward the center of the respective optoelectronic component.

[0034] This characteristic is modulated and controlled to some extent by the amount of material deposited and also by the deposition technique. For example, spin-coating, i.e., photoactive materials, can result in a different surface shape than sputtering photoactive materials, creating protrusions and bumps due to the barriers provided by the optoelectronic components. Thus, the portion of the deactivated photoactive material extending onto the top surface can include curvature, having a slope that increases toward the exposed contact area when viewed in cross-section. However, any roughness of the photoactive material surface (i.e., the distance between the lowest and highest portions) can be less than 1 μm, and particularly less than 500 nm. Attached Figure Description

[0035] Further aspects and implementations of the proposed principles will become apparent from the various embodiments and examples described in detail with reference to the accompanying drawings, in which:

[0036] Figure 1 A to Figure 1 D illustrates a method for processing the device;

[0037] Figures 2A to 2D Methods for processing the device based on some aspects of the proposed principles are shown;

[0038] Figure 3Alternative method steps during processing of the device are shown, based on some aspects of the proposed principles;

[0039] Figures 4A to 4C A top view of the optoelectronic components during processing of the device is shown, based on some aspects of the proposed principles;

[0040] Figure 5 A device with optoelectronic components embedded in such a material is shown. Detailed Implementation

[0041] The following embodiments and examples disclose various aspects and combinations thereof based on the proposed principles. The embodiments and examples are not always drawn to scale. Similarly, different elements may be shown enlarged or reduced in size to emphasize aspects. It goes without saying that the aspects of the embodiments and examples shown in the figures can be combined with each other without contradiction to the principles of the invention. Some aspects illustrate regular structures or forms. It should be noted that in practice, minor differences and deviations from the ideal form may occur; however, this does not contradict the idea of ​​the invention.

[0042] Furthermore, the various figures and aspects are not necessarily shown at the correct size, and the proportions between the elements need not be substantially accurate. Some aspects are highlighted by showing them enlarged. However, terms such as "above," "above," "below," "under," "larger," and "smaller" correctly express the elements in the figures. Therefore, such relationships between elements can be inferred from the figures.

[0043] Figure 1 A device incorporating optoelectronic components, particularly μLEDs, is shown. The μLEDs include very small diameters of less than 70 μm or even smaller, for example, but not limited to less than 20 μm or even less than 10 μm. The optoelectronic components and μLEDs are... Figure 1 A is implemented as a vertical optoelectronic component having a bottom surface 22 and a top surface 21 opposite to the bottom surface. The bottom surface and the top surface include respective contact areas, which in the present case extend along their respective entire surfaces. The optoelectronic component 20 is arranged with its bottom surface 22 and its contact areas on a corresponding contact plane 15 located on the carrier 10.

[0044] Contact plane 15 provides electrical contact with the optoelectronic component and is also connected to contact leads disposed within carrier 10. Carrier 10 may be a substrate, wafer structure, or any other suitable rigid element on which the optoelectronic component is disposed. During subsequent processing steps, a transparent dielectric layer 10a is deposited on the surface of carrier 10. Dielectric layer 10a also covers the top surface 21 of the optoelectronic component and its sidewalls. Dielectric 10a comprises SiO2 or any other suitable material. It is sputtered onto the corresponding surface to provide better wetting and contact of spin-coated glass material or dielectric material 30a, which is subsequently deposited on top of dielectric layer 10a.

[0045] Figure 1 The spin coating process shown in B results in protrusions 35a of spin-coated material on the top of surface 21 of the optoelectronic component. The protrusions 35a are formed by spin coating glass material 30a, as the total amount used for spin coating is slightly larger than the actual usable volume between the optoelectronic components on the carrier. Furthermore, the spin coating itself, as well as other surface effects between the dielectric material 10a and the spin-coated glass material 30a, may cause some material to deposit on the top surface.

[0046] In any case, it is necessary to remove excess material from the top surface. For this purpose, a plasma etching process is performed, which produces… Figure 1 The structure depicted in Figure C exposes the top surface 21 of the optoelectronic component 10. However, the plasma etching process also removes portions of the material 30a adjacent to the optoelectronic component and portions of the dielectric material 10a. Since the etching rate of the dielectric material 10a is slower than that of the spin-coated glass material 30a, edges or steps are typically formed between the optoelectronic component 20 and the dielectric material 10a, and between the dielectric material 10a and the spin-coated glass material 30a.

[0047] Therefore, during subsequent sputtering processes, such as those using an ITO conductive transparent layer, adhesion between the spin-coated glass material and the conductive transparent material near the edge of the optoelectronic component decreases. This is partly due to the exposed dielectric material 10a, which can lead to delamination between the three different materials, namely 30a, 10a, and 40. Furthermore, the step between the optoelectronic component 20 and the conductive transparent layer 40 can also cause cracks or fractures in the conductive transparent layer 40, especially since the materials used are typically brittle and prone to breakage.

[0048] Therefore, the inventors propose a new planarization embedding material for devices with multiple optoelectronic components, which can be more easily processed and has a reduced risk of delamination or breakage of transparent conductive layer materials.

[0049] Figure 5A corresponding device with optoelectronic components embedded in such a material is shown. The μLED 20 comprises a layer stack having two distinctly doped layers 26 and 27, with an active region 25 disposed between them. The respective two distinctly doped layers 26 and 27 may include various current distributions and current transport sublayers, as well as a cladding layer adjacent to the active region 25 (not shown herein). Different semiconductor materials, including group III-V semiconductor materials (such as GaN, GaP, or GaAs), are suitable, although other material systems including ternary or quaternary systems (such as InGaN, AlGaN, AlGaP, InGaP, InAlGaN, InGaAlP, or combinations thereof) may be used. The optoelectronic components are implemented as vertical μLEDs having two opposing surfaces 21 and 22, each of which includes an electrical contact. Furthermore, the surface 21 forming the top surface is roughened to provide improved light extraction.

[0050] The μLED 20 is disposed on a contact plane 15 disposed on a carrier substrate 10 with its bottom surface 22. The element 15 is connected to a contact line in an intermediate layer 11 disposed within the carrier substrate 10.

[0051] According to the proposed principle, the optoelectronic component is embedded in an inactivated photoactive material 30, which extends from the surface of the carrier substrate 10 to a level corresponding to the top surface 21 of the optoelectronic component. The term "inactivated photoactive material" refers to a photoactive material that has been treated so that irradiation of the material no longer affects its properties.

[0052] A small portion of the deactivated photoactive material 30 extends slightly onto the top surface around the edge of the optoelectronic component. The thickness of the additional material is small and can be less than 1 μm, or even less than 300 nm or even less than 100 nm. A conductive transparent layer 40 is deposited on top of the deactivated photoactive material 30 and on the top surface and contact area of ​​the optoelectronic component. The thickness of this conductive transparent layer 40 is greater than the thickness of the protrusion 32 of the deactivated photoactive material extending on the top surface. Therefore, only very small or insignificant steps are formed in the conductive transparent layer 40, thereby reducing the risk of cracking or delamination.

[0053] Figures 2A to 2DAn embodiment of a method for processing an apparatus having multiple optoelectronic components is shown. The method includes providing a carrier substrate 10 and contact elements 15, the carrier substrate 10 having multiple contact leads, and the contact elements 15 arranged in a specific structure on the surface of the carrier substrate. For example, the individual contact elements 15 may be arranged in rows and columns, with a predetermined distance between them. Using various transfer processes, the multiple optoelectronic components are attached to corresponding contact elements 15 on the carrier substrate.

[0054] like Figure 2A As shown, the bottom surface 22 of the optoelectronic component is slightly smaller than the corresponding contact element 15 on which the optoelectronic component is placed. This allows for the compensation of small tolerances or misalignments of the various components during the transfer process and ensures that the contact area on the bottom surface of each optoelectronic component is in electrical contact with the corresponding contact element 15. Solder material is used to attach the bottom surface with the contact area to the contact element.

[0055] In subsequent processing steps, photoactive material 30 is spin-coated onto the surface of the carrier substrate 10 and into the spaces between the optoelectronic components. The amount of photoactive material used is adjusted so that the total volume is slightly larger than the available volume, such that portions of the photoactive material form small protrusions 35 on the top of the optoelectronic components 20. More specifically, these protrusions 35 now resemble small hills that follow the position of the optoelectronic components and completely cover the top surface 21.

[0056] Photoactive materials are defined as materials that can be easily photostructured without requiring additional etching steps to provide their structured layers. A typical example is the silicone glass from Merck, which can be found at https: / / www.merckgroup.com / research / science-space / presentations / 2017-10-Micro-LED-Proposed-PPT-V3.pdf.

[0057] like Figure 2B As depicted, based on the proposed principles, a photomask structure 50 is now arranged above an assembly of optoelectronic components on a carrier substrate. The photomask structure 50 includes multiple transparent portions 51 (such as lenses or simple transparent windows) positioned opposite the top surface 21 of the respective optoelectronic components. The diameter of the respective transparent portions 51 is slightly smaller than the top surface 21 to again compensate for potential misalignment that could result in slightly different distances between adjacent devices during the arrangement of the optoelectronic components. Furthermore, the smaller size prevents illumination into photoactive material adjacent to the optoelectronic components, which could potentially lead to the removal of photoactive material that develops between the components.

[0058] However, the transparent portion 51 is large enough to cover the contact area on the top surface 21 even during periods of small misalignment. The photoactive material 30 is irradiated with light 55 of a specific wavelength, thereby exposing and developing the portion 36 of the photoactive material opposite the transparent portion 51. Figure 2B As shown, development causes the photoactive material 36 to cover a portion of the top surface 21, but may leave the edge portion 32 of the photoactive material undeveloped.

[0059] The developed portion is then removed using a simple removal process for the photoactive material 30, such as a solvent or gentle etching step. The irradiated and developed portion 36 will then be removed. Figure 2C Recesses 33 and openings are provided in the photoactive material on the top surface 21 of each of the various optoelectronic components shown. However, as shown, small material portions 32 are retained on the peripheral edge of the optoelectronic component 20. Such material portions 32 are relatively small in size, and their thickness can range from tens of nm to hundreds of nm. Furthermore, due to spin-coating, these portions 32 may include small curvatures or inclined surfaces, resulting in an increase in thickness along the central direction of the exposed top surface 21. It should also be noted in this respect that, in the figures, the increase in curvature and thickness is clearly excessive.

[0060] In other words, the thickness of these material portions is small, but can vary slightly, and potentially increases from the edge of the top surface 21 towards the center. However, the thickness of the photoactive material between two adjacent devices (i.e., in the middle between two components) is very small compared to the overall height difference between the top of the surface 21 of those components, and can range from a few nanometers to about 400 nm. Typically, the height difference is smaller than the thickness of the conductive layer subsequently deposited on the surface of the photoactive material 30 and the top surface of the optoelectronic component. The resulting structure is as follows: Figure 2D As shown.

[0061] The conductive transparent layer 60 comprises ITO and is sputtered onto the top surface of the photoactive material 30, thereby producing a substantially uniform thickness throughout the device. In regions 61 and 63, the thickness is approximately 50 nm to 300 nm, but can be smaller or larger depending on the overall size of the optoelectronic component and the thickness of the overlapping portion 32 on the top surface. However, the thickness is small enough that no steps or edges are generated during the sputtering process. In this respect, Figure 2D The total height distance has been magnified to show the sputtering process.

[0062] The proposed principle enables the provision of devices comprising multiple optoelectronic components on a carrier substrate using photoactive materials and conductive transparent layers deposited thereon. The photoactive material does not delaminate from the sidewalls of the optoelectronic components due to thermal or mechanical stress, thus providing a surface on which the conductive transparent layer can be deposited. Furthermore, no significant steps that could cause cracking or breakage of the conductive transparent layer are created between the sidewall edges of the optoelectronic components and the photoactive material. Instead, the conductive transparent layer can be deposited on a smooth and flat surface of both the photoactive material and the top surface of the optoelectronic components. In some additional processing steps, the photoactive material can be deactivated or otherwise treated to stabilize the material and make it resistant to oxygen or other gases or liquids.

[0063] In this method, a structured photomask layer is used to irradiate portions of the photoactive layer, and these portions are subsequently removed from the optoelectronic components. However, the process can also be reversed, in which the photoactive material 30 between the optoelectronic components (which are located above the carrier substrate) is irradiated, and the unirradiated material is subsequently removed from the top surface 21 of the optoelectronic components. Variations in this process step can depend on the photoactive material used and the subsequent stability after the fabrication and processing of the completed device.

[0064] Furthermore, due to the fixed arrangement of the transparent portions 51 regarding the position of the optoelectronic components on the carrier substrate, the photomask layer may be subject to potential misalignment.

[0065] Therefore, in some aspects, it is not used such as Figure 2B The structured photomask shown is suitable. Conversely, Figure 3 An alternative embodiment is shown in which a portion of the photoactive material 30 is specifically irradiated using a direct laser imaging device.

[0066] More specifically, in the preceding steps, and particularly before spin-coating the photoactive material onto the carrier substrate, the precise position of the optoelectronic components 20 disposed on the carrier substrate 10 is captured. Potential misalignments of some optoelectronic components are identified. Evaluation of the corresponding positions of the optoelectronic components allows for realignment of the subsequent irradiation process to ensure proper irradiation of the portion 36 of the photoactive material directly above the contact area. Thus, misalignments of the optoelectronic components during the placement step are compensated for. Figure 3 As shown, after capturing and evaluating the location, a portion 36 of the photoactive material is irradiated using a laser direct imaging device. Again, similar to the previous embodiments, a small portion 32 of the material 30 can remain unexposed to cover the edges of the optoelectronic components.

[0067] Figures 4A to 4C A top view is shown illustrating the corresponding methodological steps based on the proposed principles. (See figure.) Figure 4AAs depicted, in this embodiment, the optoelectronic component 20 is formed in a rectangular shape having a top surface 21. The photoactive material 30 completely surrounds the optoelectronic component 20 and also covers the top surface.

[0068] Figure 4B The result of irradiating a photoactive material using a photomask structure (not shown here) is illustrated, with the transparent portion 51 of the photomask structure positioned directly above the central portion of the top surface 21 of the optoelectronic component 20. In this particular embodiment, the transparent portion of the photomask structure comprises an elliptical shape and is subsequently irradiated to reveal the underlying photoactive material.

[0069] The resulting developed photoactive material portion 36 also includes an elliptical shape and is subsequently removed to expose the underlying top surface. Figure 4C The final result is shown, in which a small recess 33 is formed in the photoactive material 30 to expose the top surface 21 of the optoelectronic component 20. Furthermore, a small peripheral portion 32 remains on the top surface of the optoelectronic component.

[0070] List of reference numerals

[0071] 10. Carrier substrate

[0072] 10a dielectric material layer

[0073] 11. Intermediate Layer

[0074] 15 Contact elements

[0075] 20 Optoelectronic Components

[0076] 21 Top surface

[0077] 22 Bottom surface

[0078] 25 Active Area

[0079] 26 Doped layers

[0080] 27 Doped layer

[0081] 30 Photoactive Materials

[0082] 30a Spin-coated glass material

[0083] 32 Edge portion

[0084] 33 recess

[0085] 35, 35a protrusions

[0086] 36. Developed portion

[0087] 40 Conductive transparent layer

[0088] 50 Photomask Structure

[0089] 51 Transparent parts

[0090] 55 Light

[0091] 60 Conductive transparent layer

[0092] Areas 61 and 63

Claims

1. A method for processing an apparatus having multiple optoelectronic components, particularly μLEDs, comprising the following steps: - A plurality of vertical optoelectronic components are provided on a carrier substrate, the optoelectronic components having a contact area on a top surface opposite to the carrier substrate; - The plurality of vertical optoelectronic components are embedded in a photoactive material, the photoactive material covering the space between adjacent optoelectronic components and the top surface of the plurality of vertical optoelectronic components; - Irradiate a portion of the photoactive material above the top surface that at least partially includes the contact area; -Develop the photoactive material, thereby removing a portion of the photoactive material, such that a portion of the top surface containing at least part of the contact area is exposed; - Provide a conductive transparent layer on the remaining photoactive material and the exposed portion of the top surface to electrically contact the contact area.

2. The method according to claim 1, wherein, The steps for irradiating a portion of the body include the following: - A structured mask layer is provided on the photoactive material, such that a portion of the photoactive material above the top surface that at least partially includes the contact region can be exposed to irradiation; - Irradiation of the exposed portion of the photoactive material; 3. The method according to claim 1, wherein, The steps for irradiating a portion of the body include the following: -Provide direct laser imaging equipment; - Obtain the position of the top surface of the plurality of optoelectronic components on the carrier substrate; - Irradiate a portion of the photoactive material above the top surface, which at least partially includes the contact area, using the direct laser imaging device.

4. The method according to any one of the preceding claims, wherein, The development step includes the following steps: removing the irradiated portion, leaving the unirradiated portion of the photoactive layer on the carrier substrate; or The development step includes the following steps: removing the unirradiated portion, so that the irradiated portion of the photoactive material remains on the carrier substrate.

5. The method according to any one of the preceding claims, wherein, The steps for providing a structured mask layer include the following: - Provides a structured mask layer that includes multiple transparent sections; - The structured mask layer is disposed above the photoactive material such that each of the plurality of transparent portions is positioned above a corresponding portion of the top surface that at least partially includes the contact area, wherein the area of ​​the transparent portion is smaller than the area of ​​the top surface.

6. The method according to claim 3, wherein, Each of the plurality of transparent portions comprises a shape that is one of a circle, a rectangle, a polygon, and an ellipse.

7. The method according to any one of the preceding claims, wherein, The steps of embedding the plurality of vertical optoelectronic components into the photoactive material include: - Deposit the photoactive material such that the photoactive material forms curved protrusions above the locations of the plurality of vertical optoelectronic components; wherein, optionally, after the development step, a portion of the curved protrusions remains on the top surface.

8. The method according to any one of the preceding claims, wherein, The step of embedding the plurality of vertical optoelectronic components includes one of the following: - Spin-coating the aforementioned photoactive material; - Sputtering the photoactive material; - Distribute the photoactive material, particularly onto the top surface of the plurality of vertical optoelectronic components; - Spray the photoactive material, particularly onto the top surface of the plurality of vertical optoelectronic components; - Photoactive materials set by heat treatment, especially photoactive materials set by heat treatment after the development step.

9. The method according to any one of the preceding claims, wherein, The developing steps include: -Etching the irradiated portion of the photoactive material; -Etch the un-irradiated portion of the photoactive material; - Bake the remaining photoactive material.

10. The method according to any one of the preceding claims, wherein, The conductive transparent layer comprises ITO and is sputtered onto the remaining photoactive material such that the conductive transparent layer extends along the edge between the photoactive material and the exposed contact area on the top surface.

11. An apparatus comprising: - A carrier substrate, the carrier substrate including a plurality of contact leads; - A plurality of vertical optoelectronic components, particularly μLEDs, are arranged on the carrier substrate such that a first contact region of each of the plurality of vertical optoelectronic components is connected to a corresponding contact lead of the plurality of contact leads, wherein each of the plurality of vertical optoelectronic components includes a second contact region opposite to the first contact region; - A non-conductive, deactivated photoactive material on the carrier substrate, wherein the plurality of vertical optoelectronic components are embedded in the deactivated photoactive material, wherein a portion of the deactivated photoactive material extends to the top surface of the respective plurality of vertical optoelectronic components, thereby partially exposing the second contact region; - A conductive transparent layer that covers the exposed contact areas of the deactivated photoactive material and the plurality of vertical optoelectronic components.

12. The apparatus according to claim 11, wherein, The deactivated photoactive material includes at least one of the following: -TiO2; -SiO2; -Siloxane filler materials; and -graphite.

13. The apparatus according to any one of claims 11 to 12, wherein, The portion of the deactivated photoactive material extending onto the top surface includes curvature such that the thickness of the photoactive material partially increases toward the exposed contact area; or The portion of the deactivated photoactive material extending onto the top surface includes curvature that, when viewed in cross-sectional view, has a slope that increases toward the exposed contact area.

14. The apparatus according to any one of claims 11 to 13, wherein, The exposed area on the top surface includes one of the following shapes: -Circular; -rectangle; - Polygons; and -Oval shape.

15. The apparatus according to any one of claims 11 to 14, wherein, The transparent conductive material includes a thickness greater than ? of the steps of the deactivated photoactive material extending above the horizontal level of the top surface.

16. The apparatus according to any one of claims 11 to 15, further comprising a dielectric layer disposed on a portion of the carrier substrate and along the sidewalls and the plurality of vertical optoelectronic components.

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