Method and device for adjusting electro-optical elements on a substrate

Abstract

The invention relates to a method and to a device for providing electro-optical components on a substrate (1'). The electro-optical components (3") are oriented by means of an adjustment tool (4') in an activated state on the basis of an output signal, wherein compensation structures (2') hold the electro-optical elements during the alignment or adjustment. The invention also relates to a product substrate having a plurality of electro-optical elements.

Description

[0001] Description

[0002] Method and device for aligning electro-optical elements on a substrate

[0003] The present invention relates to a method and a device for providing electro-optical elements or components on a substrate, in particular on a product substrate.

[0004] In the current state of the art, substrates are populated with functional chips for the production of sensors and / or assembled electro-optical components. These substrates can be used as so-called interposers for heterogeneous integration. Technologies are known that describe the production and / or handling of substrates populated with chips.

[0005] Images can be generated using so-called projectors. Projectors comprise individual radiating image elements. Laser diodes, in particular, are used to project an image onto a surface. For these optical applications, especially projectors, it is not sufficient for the electro-optical components to simply function; in particular, individual semiconductor lasers on the substrate, which represent individual pixels, must illuminate. The individual electro-optical elements must be precisely aligned or adjusted, particularly to ensure uniform illumination of the projection surface and simplify the optical design without additional homogenizers.To increase the performance of electro-optical elements or projectors, particularly to increase light output with the same electrical input power or to improve color fidelity or other quality features, radiation sources with beam steering elements are encapsulated in a housing. For this purpose, electro-optical elements are integrated or fixed onto product substrates to form electro-optical components.

[0006] In the micro-manufacturing of electro-optical components, all process steps are conventionally performed on or in a single substrate, requiring technical and technological compromises in material selection and manufacturing processes. These limitations reduce the quality and performance of the electro-optical components.

[0007] For the production of radiation sources, particularly light-emitting diodes or semiconductor lasers, so-called HI-V or H-VI compound semiconductors are preferred. Due to technological limitations, such as substrate size, brittleness, fragility, and / or residual stresses in the bulk material, substrate sizes that are possible and common with silicon substrates cannot be produced. To circumvent these technological limitations and, in particular, to ensure the performance of electro-optical components, alternative processes are required, especially to enable homogeneous integration of the finished product substrate with electro-optical components.

[0008] It is therefore the object of the invention to at least partially eliminate, and in particular to completely eliminate, the disadvantages cited in the prior art. In particular, it is an object of the invention to provide improved methods and devices for providing electro-optical components on a substrate. Furthermore, it is an object of the invention to provide a method and device with which electro-optical elements can be optimally aligned or adjusted.

[0009] The present object is achieved by the features of the independent claims. Advantageous developments of the invention are specified in the dependent claims. The scope of the invention also includes all combinations of at least two features specified in the description, the claims, and / or the drawings. For specified value ranges, values ​​within the specified limits are also considered to be disclosed as limit values ​​and can be claimed in any combination.

[0010] Accordingly, the invention relates to a method for providing electro-optical components on a substrate with at least the following steps: i) providing a substrate with at least one deformable compensation structure, ii) placing an electro-optical element on the at least one compensation structure, iii) activating the electro-optical element to emit a signal, iv) detecting the signal, v) adjusting the electro-optical element, wherein the adjustment is controlled by the detected signal.

[0011] In other words, the adjustment movement is performed based on the detected signal of the electro-optical element or component. Thus, the adjustment is based on an output signal of the electro-optical element and not on the relative position of the electro-optical element to the substrate or other components. This allows for advantageous fine adjustment or alignment of the output signal. Precise alignment of the electro-optical element itself or other optical means is not necessary, since the effective direction of the outgoing signal is specifically adjusted. A substrate or product substrate with multiple electro-optical elements adjusted in this way is therefore particularly efficient and powerful.Preliminary placement on one or more deformable, preferably plastically deformable, compensation structures or height compensation structures enables fine adjustment of the signal by moving the electro-optical element. The adjustment movement is controlled by the detected signal, allowing for more precise adjustment, preferably reaching a target value.

[0012] Detection occurs in an activated state of the placed electro-optical element, in which the signal is preferably transmitted or emitted by the electro-optical element in a specific direction. After placement, the electro-optical element is received on or in the at least one compensation structure and can be adjusted using an adjustment tool based on the detected signal, ensuring that the signal can be optimally output during subsequent operation of the product substrate or the electro-optical element. After adjustment, the electro-optical element is fixed by the at least one compensation structure, so that the adjusted electro-optical element continues to output the signal optimally.

[0013] Particularly preferably, the at least one compensation structure is a polymer. Particularly preferably, several electro-optical elements are placed side by side on one or more compensation structures and adjusted according to the invention based on the signal. Particularly preferably, the electro-optical element remains activated until the completion of the adjustment process, so that the signal is emitted constantly. The method is thus ideal for use in the fine adjustment of electro-optical elements on wafers.

[0014] In a preferred embodiment of the method for providing, the signal is electromagnetic radiation. It has been found that, in particular, signals in the form of electromagnetic radiation can be optimally enhanced by adjusting the electro-optical element. The radiation is preferably a focused beam and can be continuously detected for adjustment.

[0015] In a preferred embodiment of the method for providing, the detection of the electromagnetic radiation includes the radiation direction and / or intensity of the electromagnetic radiation. In this way, not only the direction or location of the signal can be adjusted, but also the intensity can be optimally adjusted. Furthermore, detecting the intensity of the electromagnetic radiation in combination with the direction enables more precise adjustment.

[0016] In a preferred embodiment of the method for providing, the transmitted signal is directed by at least one radiation-directing element to a sensor for detecting the signal. In this way, detection can advantageously take place at another, particularly remote, location.

[0017] This also increases accuracy because the signal is directed over a longer path, allowing the particularly focused beam to be detected with increased measurement accuracy. Furthermore, detection directly at the electro-optical element is not necessary, making the method more flexible and capable of being carried out without intermediate steps. A preferred embodiment of the method for providing provides for the at least one radiation directing element to be a micro-mirror. Micro-mirrors are particularly suitable for use in the method for providing, as they enable precise measurement outside the immediate vicinity of the electro-optical element. The micro-mirror can also advantageously be integrated into the electro-optical element.

[0018] In a preferred embodiment of the method for providing, steps iv) acquisition and v) adjustment are repeated iteratively until a target value of the signal s is acquired. The step of re-acquisition after adjustment takes place in the activated state of the electro-optical element. In this way, optimal alignment or adjustment of the signal can advantageously be carried out based on the re-acquired signal until the target value is acquired.

[0019] In a preferred embodiment of the method for providing, the electro-optical element remains permanently activated during the adjustment, so that the adjustment is controlled by the continuously detected signal. In this way, an efficient and particularly precise adjustment of the signal or the electro-optical element can be performed. The signal is continuously or discretely detected by a sensor, so that the adjustment can be controlled based on the signal.

[0020] In a preferred embodiment of the method for providing, the activation comprises contacting the electro-optical element. In this way, a voltage can be applied to the electro-optical element or the electro-optical element can be supplied with current, so that the electro-optical element is activated and outputs the signal. The contacting or activation can already occur during placement, thus enabling particularly efficient adjustment.

[0021] In a preferred embodiment of the method for providing, the electro-optical element is activated by applying a voltage source, and the rated power during activation is less than 50%, preferably less than 20%, particularly preferably less than 10%, of the operating power during normal operation of the electro-optical element. In this way, the electro-optical element can be adjusted particularly gently and efficiently. Furthermore, the heat input is significantly reduced.

[0022] In a preferred embodiment of the method for providing, the electro-optical element is an LED, a semiconductor laser, a micro-LED array, or a microprojector with microlenses. The method has been found to be particularly suitable for adjusting optical fibers. Advantageously, the projection surface or the location of the light can thus be adjusted particularly precisely. Provision for a microprojector with microlenses is particularly preferred, since these can be aligned particularly precisely.

[0023] In a preferred embodiment of the method for providing, the method additionally comprises the following step vi) fixing the electro-optical element after adjustment, wherein the fixing is carried out by treating the at least one compensation structure. In other words, the material of the at least one compensation structure is solidified or cured, for example by radiation or heat treatment, so that fixing in the adjusted position is ensured. Fixing can take place after adjustment or after the target value has been reached. It is preferred that a plurality of electro-optical elements are each first adjusted on at least one compensation structure and then fixing is carried out by surface-acting treatment methods which fix all of the electro-optical elements simultaneously.The compensation structures are designed to initially hold the electro-optical elements in the adjusted position after an adjustment until the adjustment of other electro-optical elements is adjusted based on the respective signals.

[0024] In a preferred embodiment, the relative change in the position of the electro-optical elements during adjustment is less than 500 micrometers, preferably less than 100 micrometers, particularly preferably less than 25 micrometers, most particularly preferably less than 1 micrometer, and optimally less than 500 nanometers. The change in position is understood as a relative movement of the electro-optical element.

[0025] Furthermore, the invention relates to a device for providing electro-optical components on a substrate, at least comprising: a) substrate holder for receiving a substrate with compensation structures, b) placement means for placing an electro-optical element on at least one compensation structure of the compensation structures, c) activation means for activating the electro-optical element so that the electro-optical element emits a signal, d) detection means for detecting the signal, e) adjustment means for adjusting the electro-optical element, wherein the adjustment means are configured such that the adjustment means can be controlled by the detected signal.

[0026] In other words, the device is capable of optimally aligning or adjusting electro-optical elements based on their output signal. The features described in connection with the method and the associated advantages can be applied analogously to the device and its control system. The activation means thus preferably comprise, for example, contacting means for contacting the electro-optical element. A control unit of the device can also be configured as a closed-loop control system by continuously detecting the signal. Adjustment is performed, for example, by actuators.

[0027] In a preferred embodiment of the device, the placement means, the activation means, and the adjustment means are formed by an adjustment tool. In other words, the functions of placement, activation, and adjustment can be performed by a single unit. The adjustment tool preferably also includes contacting means for contacting or activating the electro-optical element. In this way, the design of the device can be simplified, and provision and adjustment can be carried out more quickly.

[0028] In a preferred embodiment of the device, the alignment tool has the detection means so that when the electro-optical elements radiate normally onto the substrate surface, the alignment tool does not obscure the radiation to be adjusted or the signal. In a preferred embodiment of the device, the detection means are configured to detect the signal during adjustment so that the alignment means can be controlled by the detection means. The activation means preferably remains continuously in operation so that the electro-optical element continuously outputs a signal. The alignment means is thus advantageously controlled on the basis of the detection means. In this way, efficient and precise provision is possible.

[0029] Furthermore, the invention relates to a product substrate, at least comprising a plurality of electro-optical elements, wherein the plurality of electro-optical elements are each fixed by compensation structures, wherein the plurality of electro-optical elements are aligned according to the method for providing electro-optical components on a substrate. The product substrate produced using the method thus has optimally aligned or aligned electro-optical elements. In this way, in particular, particularly high efficiency during operation can be ensured. Furthermore, for example, the resolution of an image can be increased. Furthermore, further optical components are not required, since the alignment provides the signal particularly suitably on a projection surface.

[0030] In the following, the components of the device and the steps of the process are described in more detail by way of example, as well as the associated advantages.

[0031] The electro-optical elements are placed individually on a substrate provided with height compensation structures. During positioning, the electro-optical elements are preferably switched on individually, and the signal from the electro-optical element is used as a control variable to adjust the position and orientation of the electro-optical element on the substrate. After adjusting all electro-optical elements on the substrate using the height compensation structures, the electro-optical elements are fixed in the adjusted or set orientation and position.

[0032] Electro-optical components or elements can be manufactured as sensors or emitters, which exhibit more precise optical characteristics. The substrate assembly is controlled, with the controlled variable being the optical signal of the electro-optical element, not the position or geometric position of the electro-optical element. This allows for better optical performance. In particular, the light output / image sharpness is improved, since the electro-optical components are aligned directly in the active state based on the output signal.

[0033] At least one broad-spectrum light-emitting diode (LED) or at least one coherent, monochromatic emitter, in particular a semiconductor laser, can be used as radiation sources for outputting the signal. The method can be used for all radiation sources of the electromagnetic spectrum, in particular X-rays, UV radiation, or visible light. For the sake of clarity of the disclosure, the radiation sources used are referred to as electro-optical elements.

[0034] Beam steering elements can include passive components such as mirrors and / or prisms and / or light guides. Beam steering elements can also include active components such as dynamically controlled micromirrors, particularly MEMS mirrors. Electro-optical elements such as LEDs or semiconductor lasers, on the one hand, and beam steering elements such as MEMS mirrors, on the other, require different substrate materials and manufacturing technologies, so joint production of the electro-optical components is neither efficient nor technologically feasible. The finished product is advantageously created through heterogeneous integration. Heterogeneous integration combines the electro-optical elements, particularly finished semiconductor laser chips, on substrates with other components to form functioning units and components.

[0035] In particular, the electro-optical components can be used for electrical, electronic, optical and / or medical applications.

[0036] The invention is based on the idea that the electro-optical elements are provided individually in the switched-on state on or in compensation structures formed on the product substrate and are adjusted based on the signal emitted in the switched-on state. The signal of the switched-on or active electro-optical element is directed or guided towards an adjustment target and measured. The electro-optical element received by the compensation structure is mechanically adjusted until the measured signal reaches a desired value in position and / or intensity at the adjustment target. In this case, the electro-optical element held by the plastically deformable compensation structure is brought by means of an adjustment device into a position in which the desired value of the output signal is reached.

[0037] The compensation structures, or height compensation structures on the product substrate, are used to accommodate an electro-optical element on a product substrate. The compensation structures adhere to the substrate and the electro-optical elements similar to a putty or adhesive. In this way, electro-optical elements can be held or provided on the substrate with the help of the compensation structures.

[0038] A key difference from adhesives is that the compensation structures possess the necessary inherent stability to maintain the position and / or orientation of an electro-optical element after alignment, similar to cementing a component to a carrier. An alignment device positions and aligns an electro-optical element through targeted plastic deformation of the compensation structures. The electro-optical elements can be at least partially embedded in the compensation structures. At the same time, the alignment in the switched-on state ensures that the respective outgoing signal of each electro-optical element optimally reaches the alignment target or is aligned within the assembly.

[0039] After the signal of the electro-optical element reaches a target value by adjusting the electro-optical element in the switched-on state, the position and orientation of the respective electro-optical element are fixed, in particular by curing the height compensation structures.

[0040] In other words, the correct alignment of the signal from the electro-optical elements and their subsequent fixation through curing are crucial for optimal functionality on the substrate. Therefore, the precise geometric arrangement of the electro-optical elements is not necessary to achieve the optimal arrangement of the output signals on the substrate or product substrate. In this way, a correctly adjusted output or signal is achieved by the aligned electro-optical element in the product substrate.

[0041] The substrates can have any shape, but are preferably circular. The diameter of the substrates is, in particular, industrially standardized. For wafers, the industry-standard diameters are 1 inch, 2 inches, 3 inches, 4 inches, 5 inches, 6 inches, 8 inches, 12 inches, and 18 inches. Rectangular panels, which can be used in particular for display production, are subsumed as substrates. The alignment method can, in principle, handle any substrate, regardless of its diameter and / or size and / or shape and / or material. The same applies to the alignment device.

[0042] A product substrate is a substrate used for the production of electro-optical components. The product substrate can contain additional structures and elements such as micromirrors or micromirror arrays, which can also be integrated onto the product substrate in a heterogeneous integration step.

[0043] The micromirrors or micromirror arrays can be direct alignment targets, so that the signals reflected by the respective micromirrors are used for alignment. During operation of the electro-optical components, the micromirrors in particular can reflect the radiation of the electro-optical elements according to their intended function.

[0044] A compensation structure is a structure in the form of a discrete elevation, which is particularly designed as an island, knob, column, cylinder and / or pyramid and can accommodate an electro-optical element. The specified shapes for a compensation structure or a height compensation structure are to be understood as examples, so that any expedient shape of the height compensation structure is conceivable and possible. In addition, it is conceivable that an electro-optical element can be accommodated by several compensation structures. Furthermore, it is conceivable that several electro-optical elements are held by one compensation structure. A repeating compensation structure with several, in particular regularly arranged elevations, each for accommodating an electro-optical element is also conceivable. In a further preferred embodiment, several individual height compensation structures accommodate one electro-optical element.

[0045] The height compensation structures can be produced using known coating methods for liquid and thin films, particularly for materials used in optical lithography. These coating methods include spin coating, spray coating, chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PE-CVD), physical vapor deposition (PVD), dip coating, doctor blade coating, and screen printing; in these methods, the material is coated onto an existing film or substrate surface either by reaction of volatile precursors or by vapor condensation.

[0046] Other coating processes are also conceivable.

[0047] The height compensation structures are preferably manufactured using thick-film technology (thick resist technology).

[0048] In a preferred embodiment, the height of the height compensation structures is less than 200 micrometers, preferably less than 100 micrometers, particularly preferably less than 50 micrometers, most preferably less than 20 micrometers, optimally less than 10 micrometers, ideally less than 1 micrometer. The height is specified relative to the support surface or the substrate surface.

[0049] In a preferred embodiment, the lateral distance between individual height compensation structures—also called "pitch"—is less than 1 mm, preferably less than 500 micrometers, particularly preferably less than 100 micrometers, most preferably less than 50 micrometers, and ideally less than 25 micrometers. The distance is specified relative to the smallest distance between the height compensation structures. In an alternative preferred embodiment, height compensation structures can be patterned on a product substrate using imprint lithography.

[0050] The height compensation structures on the substrate are preferably made of a polymer or elastomer. However, it is conceivable that height compensation structures are made of pure metals, preferably low-melting metals such as gallium, indium, or tin, metal alloys, particularly eutectic alloys or transient-liquid-phase (TLP) alloys, or composite materials. It is conceivable that the height compensation structures are made of porous or foamed material.

[0051] Preferably, a height compensation structure comprises at least one, preferably two, particularly preferably at least three, most particularly preferably at least five, ideally at least seven of the following materials:

[0052] Polymer, especially

[0053] -Acrylester-styrene-acrylonitrile, acrylonitrile / methyl methacrylate, acrylonitrile / butadiene / acrylate, -Acrylonitrile / chlorinated polyethylene / styrene, acrylonitrile-butadiene-styrene, acrylic polymers, alkyd resins, butadiene rubber, butyl rubber, casein plastics, artificial horn, cellulose acetate, cellulose ethers and derivatives, cellulose hydrate, cellulose nitrate, chitin, chitosan, chloroprene rubber, cyclo-olefin copolymers, uniform polyvinyl chloride, epoxy resin, ethylene-ethyl acrylate copolymer, ethylene-polyvinyl acetate, ethylene-propylene copolymer, ethylene-propylene-diene rubber, ethylene-vinyl acetate, expandable polystyrene, fluororubber, urea-formaldehyde resin, urea resins, Isoprene rubber, lignin, melamine-formaldehyde resin, melamine resins, methyl acrylate / butadiene / styrene, natural rubber, perfluoroalkoxylalkane, phenol-formaldehyde resin, polyacetals, polyacrylonitrile, polyamide, polybutylene succinate, polybutylene terephthalate, polycaprolactone, polycarbonate, polycarbonates, polychlorotrifluoroethylene,Polyester. Polyesteramide, polyether alcohols, polyether block amide, polyetherimide, polyether ketones, polyethersulfone, polyethylene, polyethylene, polyethylene enterephthalate, polyhydroxy alkanoate, polyhydroxybutyrate, polyimide, polyisobutylene, polylactide (polylactic acid), polymethacrylmethylimide, polymethyl methacrylate, polymethylpentene, polyoxymethylene or polyacetal, polyphenylene ether, polyphenylene sulfide, polyphthalamide, polypropylene, polypropylene copolymers, polypyrrole, polystyrene, polysulfone, polytetrafluoroethylene, polytrimethylene terephthalate, polyurethane, polyvinyl acetate, polyvinyl butyral, polyvinyl chloride (rigid PVC), polyvinyl chloride (soft PVC), polyvinylidene fluoride, polyvinylpyrrolidone, styrene-acrylonitrile copolymer, styrene-butadiene rubber, styrene-butadiene-styrene, synthetic rubber, thermoplastic Polyurethane, unsaturated polyester, vinyl acetate copolymers, vinyl chloride / ethylene / methacrylate, vinyl chloride / ethylene, vinyl chloride-vinyl acetate copolymers,Plasticized polyvinyl chloride.,

[0054] A height compensation structure may also include at least one of the following materials:

[0055] -Metal, in particular gold, silicon, silicon nitride, silicon carbide, aluminum, titanium, copper, gallium, indium, tin.

[0056] -Semiconductor material, in particular GaAs, GaNInP, InxGa l -xN, InSb, InAs, GaSb, AIN, InN, GaP, BeTe, ZnO, CuInGaSe2, ZnS, ZnSe, ZnTe, CdS, CdSe, CdTe, Hg( l -x)Cd(x)Te, BeSe, HgS, AlxGa l -xAs, GaS, GaSe, GaTe, InS, InSe, InTe, CuInSe2, CuInS2, CuInGaS2, SiC, SiGeGallium arsenide,

[0057] -Elements, especially carbon, lithium, potassium, sodium.

[0058] The material of the compensation structure or height compensation structures can, in particular, be a mixture containing at least one material and an initiator added during coating, which initiates the curing reaction of the height compensation structures. Therefore, after the height compensation structures have been produced, the product substrate should be populated with electro-optical elements and adjusted during the pot life. Particularly advantageously, the compensation structures can have a thermal conductivity that is on the order of magnitude of the product substrate and / or the electro-optical elements, so that the amount of heat generated during operation of the electro-optical elements can be dissipated into the product substrate. Thus, the thermal conductivity can be on the order of magnitude of semiconductor materials.It is particularly advantageous if the material of the height compensation structures comprises a mixture, a base material and at least one filler with high thermal conductivity.

[0059] In a particularly preferred embodiment, the material of the height compensation structures comprises metal-polymer composites with fillers. This advantageously enables deformability during alignment of the electro-optical elements, adjusted fastening, and electrical contacting with a single material.

[0060] In a particularly preferred embodiment, the height compensation structures are electrically conductive. This allows them to be advantageously used simultaneously as electrical contacts. Activation is preferably achieved by applying a voltage source.

[0061] Particularly advantageously, the compensation structures can have a thermal expansion coefficient whose value deviates by no more than 20%, preferably no more than 10%, even more preferably no more than 5%, and most preferably no more than 1% from the thermal expansion coefficient of the product substrate and / or the thermal expansion coefficient of the electro-optical elements. This allows thermal stresses in the finished product to be reduced. The reduction in thermal stresses leads to greater reliability and greater product accuracy.

[0062] A first embodiment of an exemplary manufacturing method for aligned electro-optical elements comprises at least the following steps, in particular carried out successively and / or simultaneously, preferably with the following sequence: First method step: at least one height compensation structure, preferably a plurality of height compensation structures, is produced or provided on a prepared product substrate.

[0063] Second, optional process step: the separated electro-optical elements are subjected to an initial functional test so that a sorting takes place between functional electro-optical elements and rejects.

[0064] Third process step: A positioning tool picks up an electro-optical element and moves it over the product substrate into the designated position.

[0065] Fourth process step: A tool, preferably the positioning tool, electrically contacts the electro-optical element and switches it on so that the electro-optical element generates a signal for adjustment.

[0066] Fifth process step: The positioning tool places the electro-optical element on at least one height compensation structure. To do this, the electro-optical element is brought into contact with the height compensation structure in the required position; however, the relative position and / or orientation of the electro-optical element can be slightly adjusted for adjustment.

[0067] Sixth process step: The positioning tool aligns the switched-on electro-optical element in an iterative alignment process to the alignment target, in particular to a micromirror array. A test instrument can detect the generated and / or reflected optical signal and make the necessary position corrections based on the desired intensity maximum, in particular with impact alignment. The necessary control is known to those skilled in the art. The alignment process can be considered a real-time process, since the signal from the electro-optical element and the detection can occur without any time delay. Real-time measurement and alignment can be used particularly advantageously for height compensation structures with short processing and pot life in order to utilize the machinability period.

[0068] Seventh process step: The positioning tool deactivates the electro-optical element and releases the electrical contact. Optionally, a measuring device in the positioning tool can detect and store the position and / or orientation of the electro-optical element on the product substrate in the clamped position.

[0069] Eighth process step: The positioning tool releases the mechanical clamping of the electro-optical element without moving it further or changing its position and / or orientation.

[0070] Ninth, optional method step: The position and / or orientation of the electro-optical element is checked, in particular by optical means, and if a specified tolerance is exceeded, in particular as a result of elastic relaxation and / or creep of a height compensation structure, the adjustment of the electro-optical element is carried out again iteratively.

[0071] By measuring the adjusted electro-optical element in the clamped and switched-on position, a relationship is established between the geometric position and / or orientation and the detected, in particular optical, signal, so that renewed electrical contact is not required to check the orientation and / or position of the electro-optical element.

[0072] In other words, in this method step, the position and / or orientation of the clamped, adjusted, and switched-on electro-optical element is compared with the position and / or orientation of the released electro-optical element after a specified time. If the measurement deviation exceeds a certain tolerance, the electro-optical element is readjusted. In particular, the permissible geometric position and / or orientation deviation is less than 50 micrometers, preferably less than 10 micrometers, more preferably less than 5 micrometers, most preferably less than 0.1 micrometer, and optimally less than 500 nanometers.

[0073] Tenth process step: The optical elements are fixed on / in the height compensation structures on the product substrate. In particular, the populated product substrate is exposed to crosslinking radiation. Crosslinking strengthens and crosslinks each height compensation structure. In particular, UV radiation is used for crosslinking. This initiates curing of the material of the height compensation structures and / or causes complete curing. The curing time depends on factors such as the respective thickness and / or geometry and / or material properties and / or environmental conditions such as solvent saturation and / or temperature and / or flow velocities and / or partial vapor pressures of the ambient medium. The wavelength of the curing depends on the absorbance of the photoinitiator of the material of the

[0074] Height compensation structures depend, and is preferably adjusted to the wavelength of the curing radiation.

[0075] Alternatively, height compensation structures can be made of gradually curing material, which must be processed and adjusted within a pot life. The preferred pot life is preferably less than one hour, more preferably less than 30 minutes, most preferably less than 10 minutes, and optimally less than 5 minutes.

[0076] Alternatively, height compensation structures can be made of a thermally curing material, so that a heat treatment completely cures the material. For this purpose, temperature profiles with gradients of less than 10 degrees Celsius / minute, preferably less than 5 degrees Celsius / minute, particularly preferably less than 1 degree Celsius / minute, are used. Alternatively, height compensation structures can be made of a B-stage material. Chemically speaking, the B-stage material is a one-component system that is partially cured. However, an additional process step, particularly a heat treatment, is required for complete curing.

[0077] Complete curing of the material of the height compensation structures preferably takes place at the lowest possible temperature, but above room temperature. The temperature for curing the B-stage material is less than 60°C, preferably less than 50°C, even more preferably less than 40°C, and most preferably less than 30°C.

[0078] The B-stage material can also be chemically designed so that it hardens when exposed to electromagnetic radiation, especially UV light.

[0079] For metallic height compensation structures, local heat sources can be applied to the respective height compensation structure to provide the necessary ductility during the adjustment of the electro-optical element. In this specific process, it is conceivable that at least part of the electrical contacting is achieved via the height compensation structures.

[0080] For this purpose, at least one height compensation structure for an electro-optical element can be electrically conductive, so that the height compensation structure can integrate the functions of electrical contacting of at least one of the electrical connections and the compensation of the height and / or position and / or orientation.

[0081] If exactly one contact is made between an electro-optical element and the height compensation structure, the other required electrical contacts of the electro-optical element can be manufactured using an additive process. Due to the relatively large contact area, a high specific resistance of the material can be accepted compared to purely metallic contacts. In a further preferred embodiment, the height compensation structures can therefore electrically connect the electro-optical elements to the corresponding contacts. The number of height compensation structures per electro-optical element is at least 1, preferably at least 2, more preferably at least 4, most preferably at least 8, in the further case at least 100, and optimally at least 1000. In a special case, even at least 5000 height compensation structures are conceivable.

[0082] In a preferred embodiment, the height compensation structures are at least partially electrically conductive. This advantageously allows a current flow for activation to be conducted.

[0083] In particular, each height compensation structure provides an electrical connection to a contact. However, it is also conceivable that not all height compensation structures are electrically conductive and / or establish a connection to a contact. In one case, however, each height compensation structure is electrically conductive and establishes a connection to a contact, thus simultaneously acting as a conducting element.

[0084] In a further embodiment of the provision, an electro-optical element can be aligned on a substrate with height compensation structures. In further preferred embodiments, preferably two electro-optical elements, particularly preferably four electro-optical elements, most preferably eight electro-optical elements can be mounted in alignment. Generally speaking, in the optimal case, a number of 2 nelectro-optical elements are attached in an aligned manner, where n is a natural number. The electro-optical elements are preferably all aligned according to the provision method, based on the signal after activation. The alignment method or the alignment device offers several advantages. By separating the production of the electro-optical elements from the production of the product substrates, optimized conditions can be set with regard to the substrate material, the different substrate sizes, the substrate handling and the process speeds. This means that optimal manufacturing parameters can be used for the respective components and no technological compromises have to be made. This means that the different technologies are used in a targeted manner and the components are integrated during joining, in particular homogeneously integrated.

[0085] The structuring of the product substrate for the height compensation structures is carried out primarily using thick-film technology, which is a well-known technology, especially for MEMS. Therefore, handling the structured product substrate does not require any special technologies. This also applies to metallic height compensation structures, which can be manufactured using lift-off processes.

[0086] Advantageously, the geometry and / or size and / or nature of the height compensation structures can be determined via the photomasks of the lithography and with the structured layer on the product substrate.

[0087] The geometry and / or size and / or nature of the height compensation structures can be advantageously determined using the squeegee templates.

[0088] The production of compensation structures by lamination processes is particularly preferred, as these can be efficiently applied to the product substrates.

[0089] Active or switched-on electro-optical elements can be operated, in particular, at reduced power for adjustment purposes, allowing adjustment to the signal value without the need for cooling the electro-optical element. Advantageously, an initial position of the electro-optical elements can be adjusted after positioning on the compensation structures by means of coordinated material properties or geometry of the electro-optical elements and the compensation structures, such as viscosity, ductility, affinity to one another, and / or height, particularly the diameter of the height compensation structures. In this way, the iterative positioning effort of the positioning device is minimized.

[0090] In a particularly preferred embodiment of the height compensation structures, the material of the height compensation structures has a high thermal conductivity, so that the waste heat generated during operation of the electro-optical elements is dissipated over a large area, particularly through the product substrate. The thermal conductivity is between 0.1 W / (m*K) and 5000 W / (m*K), preferably between 1 W / (m*K) and 2500 W / (m*K), more preferably between 10 W / (m*K) and 1000 W / (m*K), most preferably between 100 W / (m*K) and 450 W / (m*K).

[0091] To the extent that device features are disclosed here and / or in the subsequent description of the figures, these shall also be deemed to be disclosed as process features and vice versa.

[0092] Further advantages, features, and details of the invention will become apparent from the following description of preferred embodiments and from the drawings. In the figures, advantages and features of the invention are identified by reference numerals identifying them according to embodiments of the invention, with components or features with the same or equivalent function being identified by identical reference numerals. These show: Figures 1 a-1 c schematic representations of method steps of an exemplary method according to the invention for adjusting electro-optical elements,

[0093] Figure 2 schematic representation of a process step of the

[0094] Adjusting the alignment of an active electro-optical element.

[0095] Fig. 1a shows a schematic product substrate 1 as the result of a process step with already formed height compensation structures 2. The height compensation structures 2 can be manufactured using photolithographic thick-film technology, so that, in particular, the height tolerance of the structures is below the required alignment tolerance of the electro-optical elements. Furthermore, the height compensation structures 2 are manufactured with an excess height so that they can be deformed when accommodating the optical elements and can securely accommodate the electro-optical elements.

[0096] Fig. 1b shows an exemplary method step for assembling and aligning the product substrate 1 with the height compensation structures 2. An electro-optical element 3 is placed on the product substrate 1 above the height compensation structures 2 using a positioning and alignment tool 4. During the placement and alignment of the electro-optical element 3, the electro-optical element 3 is electronically and / or electrically contacted with the positioning and alignment tool 4 and switched on or activated in order to adjust the position and / or orientation of the electro-optical element 3 relative to the signal of the active electro-optical element. The control steps used for this purpose are known to those skilled in the art. In this way, it can advantageously be ensured that the signal of the individually aligned element is optimally aligned.Thus, the elements adjusted in this way can be aligned on the product substrate for optimal signal output.

[0097] Fig. 1c shows a process step in the production of components. On the product substrate 1, aligned electro-optical elements 3 and 3' are embedded in height compensation structures 2. During the alignment of the electro-optical elements 3 and 3', the height compensation structures 2 are plastically deformed to varying degrees depending on the alignment requirements. The position and / or orientation of each electro-optical element 3 or 3' is defined using the cured, deformed height compensation structures 2 on the product substrate 1.

[0098] Since the height compensation structures 2 adhere well to both the product substrate 1 and the electro-optical elements 3, 3' and are inherently stable after curing, the targeted plastic deformation of the height compensation structures 2 before curing enables good positioning accuracy. The electro-optical elements 3, 3' are preferably at least partially embedded in the height compensation structures 2, and the curing of the height compensation structures 2 determines their position and / or orientation on the product substrate.

[0099] In order to enable cost-effective production of electro-optical elements 3, 3', the manufacturing tolerances of the electro-optical elements 3, 3' with regard to the chip geometry and / or the precise radiation location and / or radiation position can be coarser than in the case of so-called pick and place product substrates 1 without functional adjustment of the electro-optical elements 3, 3'. Since the product substrate is populated for heterogeneous integration of the electro-optical elements 3, 3' on the product substrate 1, in particular a higher radiation yield and / or better color matching and / or better functionality of the targeted, more precisely adjusted product substrate 1 is achieved. In other words, an adjustment of the respective electro-optical element 3 or 3' is carried out on the functional variable (the emitted radiation) and not on an independent geometric orientation of the element.Therefore, the functionality and the precise alignment of the electro-optical elements 3, 3' as in Fig. 1c is ensured with a wide scattering of the geometric position and / or location of the electro-optical elements 3, 3' in relation to the product substrate 1.

[0100] In Figures 1 a-1 c, the electrical contacts and the contacting of the components were not discussed. The contacting of the components is familiar to those skilled in the art.

[0101] Fig. 2 shows a process step in the production of components. An electro-optical element 3" is placed on the product substrate 1' above the height compensation structures 2' using a positioning and adjustment tool 4'. During the placement and adjustment of the electro-optical element 3", the electro-optical element 3" is electronically and / or electrically contacted and switched on using the positioning and adjustment tool 4' in order to adjust the position and / or orientation of the electro-optical element 3" relative to an adjustment target, in particular relative to a sensor 7 using the signal 6 of the electro-optical element 3".

[0102] As an example, an indirect adjustment of the electro-optical element 3" is shown, because the signal 6 of the electro-optical element 3" is deflected by a schematically shown beam deflection element, here a micromirror 5, and thus projected onto the sensor 7. For this purpose, the electro-optical element 3" is placed in the height compensation structures 2' in the switched-on state with the positioning and adjustment tool 4' and at least partially embedded, so that the signal 6 reflected by the micromirror 5 on the sensor 7 approximates the target value within a predetermined tolerance value. List of reference symbols: 1' product substrate, 2' compensation structure, height compensation structures, 3', 3" electro-optical elements, radiation source, 4' positioning and adjustment tool, micromirror, beam steering means, radiation steering element, signal, electromagnetic radiation, light beam, sensor, sensor plate

Claims

Patent claims 1) Method for providing electro-optical components (3, 3', 3") on a substrate (1, 1') with at least the following steps: i) providing a substrate (1, 1') with at least one deformable compensation structure (2, 2'), ii) placing an electro-optical element (3, 3', 3") on the at least one compensation structure (2, 2'), iii) activating the electro-optical element (3, 3', 3") to emit a signal (6), iv) detecting the signal (6), v) adjusting the electro-optical element (3, 3', 3"), wherein the adjustment is controlled by the detected signal (6). 2) Method according to claim 1, wherein the signal (6) is electromagnetic radiation (6). 3) Method according to claim 2, wherein the detection of the electromagnetic radiation (6) comprises the radiation direction and / or intensity of the electromagnetic radiation (6). 4) Method according to at least one of the preceding claims, wherein the emitted signal (6) is directed by at least one radiation directing element (5) to a sensor (7) for detecting the signal (6). 5) Method according to at least one of the preceding claims, wherein the at least one radiation directing element (5) is a micro-mirror (5). 6) Method according to at least one of the preceding claims, wherein the steps iv) of detection and v) adjustment are repeated iteratively until a desired value of the signal (6) is detected. 7) Method according to at least one of the preceding claims 1 to 5, wherein the electro-optical element (3, 3', 3") remains permanently activated during the adjustment, so that the adjustment is controlled by the continuously detected signal (6). 8) Method according to at least one of the preceding claims, wherein the activation comprises contacting the electro-optical element (3, 3', 3"). 9) Method according to at least one of the preceding claims, wherein the activation of the electro-optical element (3, 3', 3") takes place by applying a voltage source and wherein during activation the nominal power is less than 50%, preferably less than 20%, particularly preferably less than 10% of the operating power in normal operation of the electro-optical element. 10) Method according to at least one of the preceding claims, wherein the electro-optical element (3, 3', 3") is an LED or a semiconductor laser. 1 1 ) Method according to at least one of the preceding claims, wherein the method additionally comprises the following step vi) fixing the electro-optical element (3, 3 ', 3") after the adjustment, wherein the fixing is carried out by treating the at least one compensation structure (2, 2'). 2) Device for providing electro-optical components (3, 3', 3") on a substrate (1, 1'), at least comprising: a) substrate holder for receiving the substrate (1, 1') with compensation structures (2, 2'), b) placement means (4, 4') for placing an electro-optical element (3, 3', 3") on at least one compensation structure (2, 2') of the compensation structures (2, 2'), c) activation means (4, 4') for activating the electro-optical element (3, 3', 3") so that the electro-optical element (3, 3', 3") emits a signal (6), d) detection means (7) for detecting the signal (6), e) adjustment means (4, 4') for adjusting the electro-optical element, wherein the adjusting means (4, 4') are arranged such that the adjusting means (4, 4') can be controlled by the detected signal (6). 13) Device according to claim 12, wherein the placing means (4, 4'), the activating means (4, 4') and the adjusting means (4, 4') are formed by an adjusting tool (4, 4'). 14) Device according to at least one of the preceding claims, wherein the detection means (7) are arranged to detect the signal (6) during the adjustment, so that the adjustment means (4, 4') can be controlled by the detection means (7). 5) Product substrate, at least comprising a plurality of electro-optical elements (3, 3', 3"), wherein the plurality of electro-optical elements (3, 3', 3") are each fixed by compensation structures (2, 2'), wherein the plurality of electro-optical elements (3, 3', 3") are adjusted according to the method according to one of claims 1 to 11.

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