Device, wafer and method for producing an electronic component

Abstract

The invention relates to a device. The device comprises the following features: - an annular holder (1) and a wafer (3) which is fastened in an opening (2) of the annular holder (1), wherein - the wafer (3) has a plurality of micro-components (11), - the annular holder (1) is configured to be connected to a transfer system (40), and - the transfer system (40) is configured to transfer the micro-components (11) from the wafer (3) to a further element (50). The invention also relates to a wafer and to a method for producing an electronic component.

Description

[0001] Description

[0002] DEVICE, WAFER AND METHOD FOR MANUFACTURING AN ELECTRONIC COMPONENT

[0003] A device, a wafer, and a method for manufacturing an electronic component are described.

[0004] An improved device is to be specified. In particular, a device for a simplified method for manufacturing an electronic component is to be specified, in which micro-components are transferred from one wafer to another element. Furthermore, an improved wafer is to be specified, from which micro-components are transferred to another element, particularly using a simplified method.

[0005] Furthermore, an improved method for manufacturing an electronic component is to be specified, in which, in particular, micro-components are transferred in a simplified manner from one wafer to another element.

[0006] These tasks are solved by a device having the features of claim 1, by a wafer having the features of claim 11 and by a method having the steps of claim 17.

[0007] Advantageous embodiments and further developments of the device, the wafer and the method are the subject of the dependent claims.

[0008] According to one embodiment, the device comprises an annular holder and a wafer that is secured in an opening of the annular holder. In particular, the annular holder and the wafer have a principal extension plane. Preferably, the wafer is secured in the opening of the annular holder such that the principal extension plane of the wafer and the principal extension plane of the annular holder are at least parallel to each other and / or coincide. For example, the wafer completely fills the opening of the annular holder, particularly together with an adhesive for securing the wafer in the opening.

[0009] For example, an outer circumference of the annular holder is round, oval, and / or at least partially circular. The opening of the annular holder has, in particular, the same shape as a surface of the wafer. The wafer is, in particular, mechanically stable within the opening of the annular holder. For example, an edge of the opening of the annular holder and an outer circumference of the annular holder are geometrically similar or identical to each other. Particularly preferably, the wafer and the annular holder are flush with each other at a first main surface and / or at a second main surface opposite the first main surface. In particular, the wafer can be removed from the annular holder without damage. In other words, the annular holder is, in particular, reusable.

[0010] For example, the ring-shaped holder may be made of or comprise one of the following materials: metal, ceramic, plastic, quartz glass, or sapphire. The metal could be, for example, aluminum or steel. According to another embodiment of the device, the wafer has a multitude of micro-components. In particular, the micro-components are micro-semiconductor chips. A micro-semiconductor chip has, in particular, an active zone. The active zone comprises, in particular, at least one electronic and / or optoelectronic element that forms the basis for the function of the micro-semiconductor chip. For example, the active zone is part of an epitaxial semiconductor layer sequence or another single-crystal semiconductor layer.If the micro-semiconductor chip is a light-emitting micro-semiconductor chip, such as a micro-LED, the active region typically comprises a pn junction configured to generate electromagnetic radiation. If the micro-semiconductor chip is, for example, a micro-IC (IC being short for "integrated circuit"), the active region comprises at least one electronic component of a circuit, such as a diode, a transistor, a voltage regulator, a rectifier, and / or a resistor. In the case of a micro-IC, the active region is, for example, enclosed by a single-crystal silicon layer.

[0011] The epitaxial semiconductor layer sequence is grown epitaxially on a growth substrate. The micro-component is characterized in particular by the fact that the growth substrate is located away from the epitaxial semiconductor layer sequence. Furthermore, the micro-component is preferably free of a mechanically stabilizing support as an alternative to a growth substrate. A typical thickness of a micro-component is therefore, for example, between 1.5 micrometers and 25 micrometers. The micro-component is characterized in particular by its exceptionally small dimensions. For example, the edge length of a micro-component in a top view of the active zone is less than or equal to 100 micrometers, or less than or equal to 70 micrometers, or less than or equal to 50 micrometers.

[0012] In particular, micro-components are provided on carrier wafers with holding structures that can be removed without damaging the micro-components. Besides the term micro-component, the following notations can also be used, for example: ^component, p-component, u-component, u-component.

[0013] For example, the micro components include micro-LEDs, micro-converters and / or micro-ICs.

[0014] The micro-converter is specifically designed to convert electromagnetic radiation of a first wavelength range into electromagnetic radiation of a second wavelength range that differs from the first. In other words, the micro-converter is wavelength-converting. For example, the micro-converter incorporates a wavelength-conversion phosphor. The phosphor is, for instance, part of a wavelength-converting layer of the micro-converter. In particular, the phosphor can be a quantum dot phosphor.

[0015] According to another embodiment, the wafer has a large number of micro-components. These micro-components can be identical or different from one another. Preferably, the micro-components cover as large an area of ​​the wafer as possible. In particular, at least part of the wafer's edge is covered with micro-components.

[0016] According to another embodiment of the device, the ring-shaped holder is configured to be connected to a transfer system. For example, the ring-shaped holder has connecting elements designed for connection to mounting elements of the transfer system. The transfer system is specifically configured to transfer the micro-components from the wafer to another element, for example, a target wafer. For example, the transfer system includes a laser, a punch, and / or a heating device for transferring the micro-components.

[0017] According to one embodiment, the device comprises an annular holder and a wafer that is secured in the opening of the annular holder. The wafer also contains numerous micro-components, and the annular holder is configured to connect to the transfer system. In this embodiment, the transfer system is configured to transfer the micro-components from the wafer to the next element, such as a target wafer or target substrate.

[0018] One of the proposed solutions is to use a ring-shaped holder for the wafer to secure it in the transfer system. This allows the wafer to be precisely aligned and positioned very close to a target wafer for laser transfer, as explained in more detail below. Furthermore, the ring-shaped holder enables the placement of as many micro-components as possible within the wafer, thus maximizing surface utilization. Additionally, the use of the ring-shaped holder allows for the processing of wafers of varying sizes in the same transfer system, as the wafer's surface area can be adapted to the system's dimensions. In particular, this eliminates the need for a foil, onto which the micro-components must be transferred in other processes.

[0019] According to one embodiment of the device, the micro-components are micro-LEDs.

[0020] A micro-LED, for example, is any light-emitting diode (abbreviated "LED") with particularly small dimensions. Generally, a micro-LED is not a laser that generates electromagnetic laser radiation through stimulated emission.

[0021] In the usual case - this is also a very important criterion besides size - the growth substrate is removed in micro-LEDs, so that typical thicknesses of such micro-LEDs are, for example, in the range of 1.5 micrometers to 25 micrometers.

[0022] A micro-LED does not necessarily have to have a rectangular emission surface. For example, a micro-LED can have an emission surface where, viewed from above the active zone, each lateral extent of the emission surface is less than or equal to 100 micrometers or less than or equal to 70 micrometers. For rectangular micro-LEDs, for example, an edge length of less than or equal to 70 micrometers or less than or equal to 50 micrometers is often cited as a criterion, particularly when viewed from above the active zone.

[0023] Most of these micro-LEDs are provided on carrier wafers with holding structures that can be removed without damaging the micro-LED.

[0024] Currently, the primary application for micro-LEDs is in displays. Micro-LEDs form pixels or subpixels and emit light of a defined color. Due to their small pixel size and high density with close spacing, micro-LEDs are suitable for small monolithic displays for AR applications (AR stands for "augmented reality"), particularly smart glasses. Further applications are also being developed, especially in data communication and pixelated lighting applications.

[0025] In the literature you will find various spellings for “micro-LED”, e.g. pLED, p-LED, uLED, u-LED or Micro Light Emitting Diode.

[0026] According to one embodiment of the device, the wafer is fixed in the opening of the annular holder with an adhesive, in particular in a mechanically stable and reversible manner. For example, the adhesive completely surrounds the opening of the annular holder. The adhesive achieves, in particular, a mechanically stable and material-bonded connection between an edge of the wafer and the opening of the annular holder. For example, the adhesive completely fills a gap between the wafer and the annular holder. For example, the adhesive is a polymeric material that can be cured by UV light, a catalyst, or heat. For example, the adhesive is a transparent acrylate adhesive.

[0027] According to another embodiment of the device, an edge of the wafer has a first chamfer. The edge delimits the wafer, in particular in a lateral direction that runs in the principal extension plane of the wafer. For example, the chamfer is formed along the entire edge of the wafer. The edge of the wafer can also be straight or rounded, for example, without a chamfer. The first chamfer of the edge of the wafer comprises, in particular, a first beveled partial surface of the edge, which extends, in particular, from a first principal surface of the wafer to a side surface of the wafer.

[0028] The first chamfer of the wafer edge rests, in particular, on a foot of the annular holder. Specifically, the foot has an inclined outer surface on which the chamfer of the wafer edge is in direct contact and preferably fully supported. The annular holder is designed to be inserted into the transfer system with its foot facing downwards along a direction of gravity. Thus, the foot contributes to fixing the wafer in the transfer system. The foot forms, in particular, a projection of the annular holder that extends into the opening of the annular holder. For example, the foot extends along the entire opening of the wafer. In this embodiment of the device, for example, the edge of the wafer is further mechanically secured by an adhesive to a second main surface, which faces away from the first chamfer of the wafer edge.The adhesive, which provides an additional mechanically stable bond between the wafer and the ring-shaped holder, can be applied either at specific points or completely around the entire circumference when viewed from above. For example, in this embodiment, the adhesive is at least partially positioned between the ring-shaped holder and the edge of the wafer.

[0029] According to another embodiment of the device, the edge of the wafer has a second chamfer. For example, the chamfer is formed as a second beveled portion of the edge, extending from the second main surface of the wafer. For example, the second chamfer is symmetrical to the first chamfer. In this embodiment as well, the wafer is attached to the ring-shaped holder, for example, with an adhesive. In particular, the adhesive fills a gap between the ring-shaped holder and the wafer, for example, completely.

[0030] According to another embodiment, the ring-shaped holder has a bevel on one of its outer surfaces. This bevel is specifically designed to secure the device in the transfer system. For example, the bevel on the outer surface runs parallel to a sloping support surface of the base. Specifically, the bevel is intended to be installed in the transfer system facing downwards along the direction of gravity. According to yet another embodiment of the device, the wafer is clamped in the ring-shaped holder. In this embodiment, the wafer is not attached to the ring-shaped holder with an adhesive or any other joining element, but is in direct contact with the ring-shaped holder.Particularly preferably, in this embodiment, the wafer has a first chamfer and a second chamfer extending from two opposing main faces of the wafer, such that the edge of the wafer has two inclined, converging partial surfaces. In this embodiment, the ring-shaped holder also preferably has two inclined partial surfaces at its opening, on which the first chamfer and the second chamfer of the wafer's edge rest.

[0031] According to another embodiment, the ring-shaped holder has at least two parts that are mechanically stably connected to each other with an adhesive and / or a fastening element. In particular, this

[0032] The design consists of a ring-shaped holder with a clamped connection between the wafer and the ring-shaped holder. A screw or a clamp, for example, can be used as the fastening element. In particular, the fastening element is designed to allow the two parts of the ring-shaped holder to be separated from each other without causing damage.

[0033] According to another embodiment of the device, the ring-shaped holder has at least three cover elements that partially cover the wafer. In this

[0034] In this design, the cover elements are preferably mechanically bonded to the wafer using an adhesive. In particular, the cover elements extend from the annular holder over the first and / or second main surface of the wafer. This allows for point fixing of the wafer in the annular holder, thus reducing the area that cannot be covered with micro-components due to the wafer's fixation in the annular holder. For example, the cover elements are designed as projections with a semicircular base.

[0035] According to another embodiment of the device, a lower main surface of the wafer is flush with the annular holder. In particular, the lower main surface of the wafer is configured to be installed in the transfer system so that it points towards a target wafer. Specifically, the wafer's micro-components are arranged closer to the lower main surface of the wafer than to an upper main surface of the wafer opposite the lower main surface. If the lower main surface of the wafer is flush with the annular holder, the device does not collide with the target wafer and simultaneously exhibits high stability.

[0036] One idea of ​​the present application is to use an annular holder to install the wafer, from which the micro-components are to be transferred to another element, into the transfer system. However, it is also possible for the wafer to be installed directly into the transfer system, for example, by mechanically connecting the wafer to mounting elements of the transfer system in a stable manner. A corresponding wafer is disclosed below. All embodiments of the wafer disclosed here in connection with the device can also be implemented on the wafer alone, and vice versa. According to one embodiment, the wafer comprises a plurality of micro-components and at least three connection areas designed for a mechanically stable connection with a transfer system. In particular, the connection areas are arranged on an edge of the wafer.The micro-components can be identical or different. Preferably, at least one central area of ​​the wafer is completely covered with micro-components. Likewise, a peripheral area of ​​the wafer surrounding the central area is covered with micro-components, except for the connection areas. This allows for the most complete possible coverage of the wafer with micro-components. The three connection areas are specifically designed to be separate from one another and are separated, for example, by portions of the peripheral area that are covered with micro-components.

[0037] According to another embodiment of the wafer, each connection area has a first chamfer and a second chamfer on one edge of the wafer. In other words, the edge of the wafer has a double chamfer in each of the connection areas. Specifically, the edge of the wafer is chamfered from both main surfaces at three different locations that form the connection areas, so that the wafer is designed to be installed in the transfer system at these locations. For this purpose, the transfer system includes, in particular, mounting elements with inclined bearing surfaces for the first chamfer and the second chamfer of the connection areas. For example, the wafer has exactly four connection areas, each opposite the other. If the wafer has only three connection areas, these are particularly preferably arranged regularly along the edge of the wafer.

[0038] According to another wafer design, the micro-components are attached to a support wafer by means of retention structures. In particular, the support wafer is transparent to electromagnetic radiation, for example, from the ultraviolet spectral range. For example, the support wafer is a sapphire wafer. The retention structures are made of, for example, a polymeric material. The polymeric material is, for example, benzocyclobutene (BCB) or polyimide (PI). In particular, the retention structures are part of a polymeric layer system that contains the same material as the retention structures or is made of the same material as the retention structures.

[0039] In addition to the retention structures, the polymer layer system includes, for example, an assembly layer from which the retention structures extend. The assembly layer is, for example, formed across the entire surface between the support wafer and the micro-components. In particular, recesses, which are, for example, air-filled, are arranged between the assembly layer and the micro-components. Furthermore, it is possible that the polymer layer structure includes separating elements that extend from the assembly layer as frame-shaped projections between the micro-components, particularly in the same direction as the retention structures.

[0040] According to another wafer design, the micro-components are attached to the carrier wafer via the mounting layer. For example, the mounting layer is in direct contact with the carrier wafer, particularly across its entire surface. The mounting layer is also in direct contact with the micro-components. Specifically, there are no gaps between the mounting layer of the polymer layer structure and the micro-components.

[0041] According to another wafer design, a material of the support structures and / or a material of the assembly layer is designed to be dissolved by irradiation with electromagnetic laser radiation. For example, the material of the support structures and / or the material of the assembly layer is BCB or a polyimide.

[0042] According to another embodiment, the wafer comprises at least three measuring areas that are free of micro-components. These measuring areas are specifically designed for distance measurement and / or tilt measurement, particularly with the aid of a confocal sensor. In other words, the measuring areas are configured to determine a tilt of the wafer using a confocal sensor, for example, relative to a target wafer.

[0043] The measuring areas are located, in particular, at the edge of the wafer. For example, the measuring areas of the wafer may be formed only by portions of the carrier wafer. Furthermore, it is also possible that only a mounting layer of the polymer layer structure is present in the measuring area. It is also possible that the polymer layer structure in the measuring area is formed as in the rest of the wafer and, in addition to the mounting layer, includes retaining structures and / or separating elements. The device and the wafer are specifically designed to be used in a process for manufacturing an electronic component. Consequently, all features and embodiments described in connection with the device and / or the wafer can also be implemented in the process, and vice versa.

[0044] According to one implementation of the method, a micro-component is transferred from a device and / or a wafer to another element. In particular, the method involves the sequential transfer of several micro-components from the device and / or the wafer to the other element.

[0045] In particular, the micro-components form functional elements in the electronic component being manufactured. If the micro-components are micro-LEDs, they form, for example, the pixels of a display.

[0046] In particular, the micro-components can be transferred precisely and cost-effectively to another element such as the target wafer using this method, according to freely defined patterns.

[0047] According to one implementation of the process, the transfer of the micro-components to the other element takes place with the aid of a laser. For example, holding structures and / or a mounting layer and / or other parts of a polymer layer structure are at least partially dissolved with the aid of the laser, so that a pulse is transferred to the micro-component to be transferred, causing it to detach from the wafer and in particular from the polymer layer structure and be transferred to the other element.

[0048] Alternatively, the transfer of the micro-components to the next element can also be achieved using a stamp, such as a silicone stamp. In this implementation of the process, the micro-components are connected to the support wafer, particularly by retaining structures, which are broken open by the stamp. Another possibility is to expand a gas, for example air, located in a cavity between the retaining structures and the micro-components, for example by heating, so that the retaining structures also detach and the micro-components are transferred to the next element.

[0049] According to another embodiment of the method, the additional element is a target wafer arranged parallel to the wafer. In particular, both the wafer and the target wafer are placed in a transfer system. The distance between the wafer and the target wafer is, for example, between 50 micrometers and 150 micrometers. Such a small distance is particularly necessary when the transfer is carried out using a laser.

[0050] According to another embodiment of the method, a tilt of the wafer relative to the target wafer is determined and, in particular, corrected. Here, measurement areas of the wafer are used where a tilt of the wafer relative to the target wafer is determined, for example, with the aid of a conical sensor. Electronic components with micro-LEDs as active elements can be produced using this method. Such electronic components can be, for example, transparent and opaque symbols and characters, as well as luminescent films.

[0051] Furthermore, white micro-LEDs, micro-converters, micro-ICs, and other micro-components can be fabricated using this method. The finished electronic components can be used, for example, in the automotive sector, in industry, in displays, and in consumer products. These electronic components can also be used in ambient lighting, RGB displays, headlights, displays, and projectors.

[0052] Further advantageous embodiments and developments of the device, the wafer and the method result from the exemplary embodiments described below in conjunction with the figures.

[0053] Figures 1 and 2 show schematic views of a device according to an exemplary embodiment.

[0054] Figures 3 and 4 show schematic sectional views of a wafer according to two exemplary designs.

[0055] Figures 5 and 6 show schematic views of a wafer according to a further embodiment.

[0056] Figure 7 shows a schematic sectional view of a wafer according to another embodiment. Figures 8 to 13 show schematic sectional views of a device according to various embodiments.

[0057] Figures 14 and 15 show schematic views of a device according to a further embodiment.

[0058] Figures 16 and 17 show schematic views of a wafer in a transfer system according to an exemplary embodiment.

[0059] Figure 18 shows a schematic representation of a stage of a process according to an exemplary embodiment.

[0060] Figures 19 and 20 show schematic representations of a device according to an exemplary embodiment.

[0061] Figures 21, 22 and 23 schematically show measurements of a tilting of the wafer according to various exemplary embodiments.

[0062] Identical, similar, or similarly functioning elements are marked with the same reference symbols in the figures. The figures and the relative sizes of the elements depicted within them are not to be considered to scale. Rather, individual elements, particularly layer thicknesses, may be exaggerated for clarity and / or better understanding.

[0063] The device according to the embodiment shown in Figures 1 and 2 has an annular holder 1 with an opening 2. Figure 2 shows a sectional view of the device according to Figure 1 along section line AA. A wafer 3 is fixed in the opening 2 of the annular holder 1 with an adhesive 4. In particular, the wafer 3 is mechanically stable in the opening 2 of the annular holder 1 by the adhesive 4. The adhesive 4 is arranged completely around the perimeter between the wafer 3 and the annular holder 1. The wafer 3, together with the adhesive 4, completely fills the opening 2 of the annular holder 1.

[0064] The annular holder 1 includes a positioning element 5 that engages in a notch 6 of the wafer 3. The positioning element 5 serves to align the wafer 3 in the annular holder 1. The wafer 3 also has three measuring areas 7, which are configured for tilt measurement (Figure 1).

[0065] The wafer 3 has a functional layer 8 arranged on a support wafer 9. The support wafer 9 is transparent to ultraviolet radiation. An outer surface 10 of the support wafer 9 is polished. The functional layer 8 comprises a multitude of micro-components 11. A lower main surface 56 of the wafer 3 is flush with the annular holder 1. The micro-components 11 are arranged closer to the lower main surface 56 of the wafer 3 than to an upper main surface 57 of the wafer 3, which is opposite the lower main surface 56. The design of the functional layer 8 and the micro-components 11 is explained in more detail below with reference to Figures 3 to 7, which show the section of the wafer 3 labeled B in Figure 2 in greater detail.

[0066] The wafer 3 according to the embodiment shown in Figure 3 has a carrier wafer 9. Furthermore, the wafer 3 comprises micro-components 11, which in this case are configured as micro-LEDs 12.

[0067] The micro-LED 12 has an epitaxial semiconductor layer sequence 13 with an active zone 14 that generates electromagnetic radiation during operation. A metal mirror 15 is arranged on a rear main surface and on side surfaces of the micro-LED 12, which directs the electromagnetic radiation generated in the active zone 14 towards a radiation emission surface 16 of the micro-LED 12. Electrical contacts 17 are also arranged on the rear main surface, which are configured to electrically connect the micro-LEDs 12 to electrical terminals of another element. A passivation layer 18 is applied over the metal mirror 15. A passivation layer 19 is also applied over the entire surface of the radiation emission surface 16 of the micro-LED 12.

[0068] The wafer 3 according to the embodiment shown in Figure 3 further comprises a polymeric layer structure 20 with holding structures 21, a mounting layer 22 and separating elements 23.

[0069] The mounting layer 22 is fully and integrally bonded to the carrier wafer 9. The retaining structures 21 extend from the mounting layer 22 and connect the micro-LEDs 12 to the carrier wafer 9. Air-filled recesses 24 are arranged between the mounting layer 22 and the micro-LEDs 12. Furthermore, a separating element 23 is arranged between each pair of directly adjacent micro-LEDs 12, extending along the side faces of the micro-LEDs 12. The wafer 3 according to the embodiment shown in Figure 4 differs from the wafer according to the embodiment shown in Figure 3 in the configuration of the polymeric layer structure 20. In particular, the polymeric layer structure 20 does not have any retaining structures 21. Rather, the mounting layer 22 is in direct contact not only with the carrier wafer 9 but also with the micro-LEDs 12. The micro-LEDs 12 are partially embedded in the polymer layer structure 20.

[0070] In contrast to the wafer 3 shown in Figures 5 and 6, the wafer 3 according to the embodiment shown in Figure 4 has recesses 24 between the polymer layer structure 20 and the micro-LEDs 12. The recesses 24 are, for example, filled with air (Figure 5). Figure 6 shows a top view of the wafer 3 according to Figure 5.

[0071] Furthermore, the wafer 3 has a fully applied interconnect layer 25, which mechanically connects the micro-LEDs 12 to separating elements 23 of a polymeric layer structure 20. The separating elements 23 form anchors 26, which mechanically connect the interconnect layer 25 to the carrier wafer 9. In the area of ​​the separating elements 23, the interconnect layer 25 forms retaining straps 27, which are particularly strip-shaped and span the recesses 24 (Figure 6). The interconnect layer 25 comprises, for example, a metal, oxide, or nitride such as SiNx, or consists of one of these materials.

[0072] In this case, the compound layer 25 replaces the passivation layer 19 and performs its function in the micro-LEDs 12. The wafer 3 according to the embodiment shown in Figure 7, unlike the wafer 3 according to the embodiment shown in Figures 5 and 6, has a sacrificial layer 28 arranged between the micro-LEDs 12 and the polymeric layer structure 20. For example, the sacrificial layer 28 comprises or consists of a nitride, such as SiNx, or an oxide, such as TiO2. The sacrificial layer can also comprise or consist of a polymer or silicon.

[0073] Figures 8 to 13 show sections of a device with an annular holder 1 and a wafer 3, which is secured in an opening 2 of the annular holder 1. In particular, the figures show the connection between the annular holder 1 and the wafer 3.

[0074] In the device according to the embodiment shown in Figure 8, the wafer 3 is attached to the annular holder 1 by means of an adhesive 4. Specifically, the adhesive 4 is arranged in a gap 29 between the annular holder 1 and an edge 30 of the wafer 3 and completely fills this gap. On a second main surface 31 of the wafer 3, which is opposite a first main surface 32 of the wafer 3, the adhesive 4 forms a meniscus 33. In this case, the second main surface is the upper main surface 57 of the wafer 3 and the first main surface is the lower main surface 56 of the wafer 3.

[0075] In the device according to the embodiment shown in Figure 9, the annular holder 1 has a base 34 with an inclined support surface 35. Furthermore, the wafer 3 has a first chamfer 36 along an edge 30. The first chamfer 36 has an inclined partial surface 37 extending from a first main surface 32 of the wafer 3. The chamfered partial surface 37 of the first chamfer 36 rests in direct contact with the support surface 35 of the base 34. The device also includes an adhesive 4 for mechanically fixing the wafer 3 in an opening 2 of the annular holder 1, which extends from a second main surface 31 of the wafer 3 to the annular holder 1.

[0076] The device according to the embodiment shown in Figure 10, unlike the device according to the embodiment shown in Figure 9, has an annular holder 1 in which an outer surface 38 has a slope 39. The slope 39 runs parallel to the inclined partial surface 37 of the first chamfer 36 of the wafer 3. In particular, the slope 39 of the annular holder 1 is designed to secure the annular holder 1 in a transfer system 40 by directing it downwards in the direction of a gravitational force G. F provided (compare Figure 18). Furthermore, the adhesive 4 extends completely into a gap 29 between the annular holder 1 and the edge 30 of the wafer 3. This results in a particularly good fixation of the wafer 3 in the opening 2 of the annular holder 1.

[0077] The device according to the embodiment shown in Figure 11, unlike the device in Figure 9, has a wafer 3 with a second chamfer 41 at its edge 30, which has an inclined partial surface 37 extending from a second main surface 31 of the wafer 3. In other words, the wafer 3 according to Figure 11 has two chamfers 36, 41 formed at an edge 30 of the wafer 3. In this device, the adhesive 4 not only fills a gap 29 between the edge 30 of the wafer 3 and the annular holder 1, but also a cavity 42, which is bounded by the inclined partial surface 37 of the second chamfer 41 and an inner surface 43 of the annular holder 1. This ensures particularly good anchoring of the wafer 3 in the opening 2 of the ring-shaped holder 1.

[0078] In the devices according to the embodiments of Figures 12 and 13, the wafer 3 is mechanically fixed in the opening 2 of the annular holder 1 by a clamping mechanism, unlike in the devices according to embodiments 8 to 11, and not by an adhesive 4.

[0079] The devices of Figures 12 and 13 comprise a wafer 3 whose edge 30 has a first chamfer 36 and a second chamfer 41. The two chamfers 36, 41 each extend from a main surface 31, 32 of the wafer 3 towards the edge 30, so that the cross-sectional area of ​​the wafer 3 decreases continuously in the region of the edge 30. An edge 30 of the wafer 3 is in direct contact with an inner surface 43 of the annular holder 1, in particular with the inclined partial surfaces 37 of the chamfers 36, 41.

[0080] Furthermore, the ring-shaped holder 1 of the device according to the embodiment of figure 12 has two sections 44 which are symmetrically formed to each other and are mechanically stable connected with an adhesive 4.

[0081] In contrast to the device shown in Figure 12, the device according to the embodiment shown in Figure 13 has a fastening element 45, for example a screw, which mechanically connects the two parts 44 of the ring-shaped holder 1 in a stable and reversible manner.

[0082] The device according to the embodiment shown in Figures 14 and 15 has an annular holder 1 with cover elements 46, which extend partially over a second main surface 31 of the wafer 3 and are mechanically stably connected to it only in the area of ​​the cover elements 46 by an adhesive 4. Figure 14 shows a top view of the device and Figure 15 shows a section of a sectional view in the area of ​​a cover element 46.

[0083] Figures 16 and 17 show an embodiment of a wafer 3 which is inserted directly into a transfer system 40 without an annular holder 1, in this case by clamping it into mounting elements 47 of the transfer system 40.

[0084] The wafer 3 has, in particular, four connection areas 48, which are arranged opposite each other on the edge 30 of the wafer 3. Each connection area 48 has a first chamfer 36 and a second chamfer 41, as shown in Figure 17. Between the connection areas 48, the edge 30 of the wafer 3 is formed without a chamfer. This makes it possible, in particular, to arrange micro-components 11 on the wafer 3 in those parts of an edge region 49 where no connection area 48 is provided.

[0085] Figure 17 shows a section in which the wafer 3 with a connection area 48 is inserted into a mounting element 47 of a transfer system 40 by means of a clamping. The mounting element 47 has inclined surfaces for clamping the double chamfer. In the method according to Figure 18, a device, such as that already described with reference to Figures 1 and 2, is inserted into a transfer system 40. The wafer 3 is designed, for example, as described with reference to Figure 3.

[0086] Furthermore, the transfer system 40 contains an element 50 onto which at least one micro-LED 12 from wafer 3 is transferred using the method. This element 50 is a target wafer 51, which is also mechanically stable mounted in the transfer system 40. Wafer 3 and target wafer 51 are arranged parallel to each other and have a very small distance D between them, for example, between 50 micrometers and 150 micrometers. The target wafer 51 is held in place by a gravitational force F. G The arrangement is positioned below wafer 3. However, it can also be arranged upside down or vertically, so that the process is practically unaffected by gravity.

[0087] Furthermore, the transfer system 40 includes a laser 52 which, during operation, emits electromagnetic laser radiation 53, for example, from the UV range. The electromagnetic laser radiation 52 passes through a carrier wafer 9 of the wafer 3 and encounters a polymer layer structure 20 of the wafer 3, which is dissolved by the irradiation with the electromagnetic laser radiation 53, so that a micro-LED 12 is transferred to the target wafer 51.

[0088] The laser 52 is directed in a horizontal direction R. H The micro-LEDs 12 are moved across wafer 3, so that several micro-LEDs 12 are successively transferred to the target wafer 51 in further steps. In these further steps, several micro-LEDs 12 are transferred successively to the target wafer 51 in a freely programmable pattern.

[0089] To obtain electronic components that are as free of defects as possible in the method according to the embodiment shown in Figure 18, it is advantageous, due to the small distance D between the device and the target wafer 51, that these are arranged as parallel to each other as possible. Therefore, methods for determining a tilt of the wafer 3 in the annular holder 1 are described in more detail with reference to Figures 19 to 23.

[0090] Figures 19 and 20 show schematic representations of a device with a wafer 3 whose tilt relative to a target wafer 51 is determined. The device is configured, for example, as already described with reference to Figures 1 and 2. In particular, the wafer 3 has three measuring areas 7. One measuring area 7 is included in section B of Figures 19 and 20 and is shown in detail in Figures 21, 22, and 23.

[0091] Figure 21 shows a schematic sectional view of wafer 3 in measuring area 7 and a section of an opposite target wafer 51. For example, wafer 3 and target wafer 51 are mounted in a transfer system 40, as already described with reference to Figure 18.

[0092] In the wafer 3 according to the embodiment shown in Figure 21, the micro-components 11 are removed from the measuring area 7, so that only the polymer layer structure 20 with a mounting layer 22, retaining structures 21 and separating elements 23 are arranged on the carrier wafer 9. The rest of the wafer 3 is formed as already described with reference to Figure 3.

[0093] For tilt measurement, a confocal sensor 54 is used, with which two different confocal reflections RI and R2 are generated within the measuring range. The confocal sensor 54 is also included by the transfer system 40. A first confocal reflection RI is generated at an outer surface 10 of the carrier wafer 9, and a second confocal reflection R2 is generated at the polymer layer structure 20. Finally, a third confocal reflection R3 is generated at a main surface 55 of the target wafer 51, which faces the wafer 3. From the three confocal reflections RI, R2, and R3, a distance D between wafer 3 and the target wafer 51 is determined in measuring range 7. Wafer 3 has a total of three measuring ranges 7, and the distance D between wafer 3 and target wafer 51 is determined in all three measuring ranges 7. From the determined distances D, a tilting of wafer 3 relative to the target wafer 51 can then be determined and corrected.

[0094] In the embodiment shown in Figure 22, in contrast to the embodiment shown in Figure 21, a material of the polymeric layer structure 20 is applied in an unstructured manner in the measuring area 7, so that it is flush with a radiation emission surface 16 of the micro-LEDs 12.

[0095] In this embodiment, a fourth confocal reflection R4 is additionally generated at an outer surface of the polymer layer structure 20 during distance measurement. In the embodiment according to Figure 23, the polymer layer structure 20 is completely removed in the measuring area 7. A first confocal reflection RI is determined at an outer surface 10 of the support wafer 9, a second confocal reflection R2 at a main surface of the support wafer 9 opposite the outer surface 10, and a third confocal reflection R3 at a main surface 55 of the target wafer 51 for tilt measurement.

[0096] The present application claims priority over German application DE 102024117724 . 1 , the disclosure content of which is hereby incorporated by reference.

[0097] The invention is not limited to the description provided by the exemplary embodiments. Rather, the invention encompasses every new feature as well as every combination of features, which in particular includes every combination of features in the patent claims, even if that feature or combination itself is not explicitly specified in the patent claims or exemplary embodiments.

[0098] Reference character list

[0099] 1 ring-shaped holder

[0100] 2 Opening

[0101] 3 wafers

[0102] 4 adhesive

[0103] 5 Positioning element

[0104] 6 Notch of the wafer

[0105] 7 Measuring range

[0106] 8 functional layers

[0107] 9 carrier wafers

[0108] 10 Outer surface of the carrier wafer

[0109] 11 micro-component

[0110] 12 micro-LEDs

[0111] 13 epitaxial semiconductor layer sequence

[0112] 14 active zones

[0113] 15 metal mirrors

[0114] 16 Radiation emission surface

[0115] 17 electrical contact

[0116] 18 Passivation

[0117] 19 Passivation layer

[0118] 20 polymer layer structure

[0119] 21 Support structure

[0120] 22 Assembly layer

[0121] 23 Separating element

[0122] 24 Exclusion

[0123] 25 Compound layer

[0124] 26 anchors

[0125] 27 Restraint strap

[0126] 28 Victim class

[0127] 29 gap

[0128] 30 Edge of the wafer

[0129] 31 second main surface of the wafer 32 first main surface of the wafer

[0130] 33 Meniscus

[0131] 34 feet

[0132] 35 inclined support surface

[0133] 36 first phase

[0134] 37 inclined part surface

[0135] 38 Outer surface of the ring-shaped holder

[0136] 39 Slanted

[0137] 40 Transfer system

[0138] 41 second phase

[0139] 42 cavities

[0140] 43 Inner surface of the ring-shaped holder

[0141] 44 sections

[0142] 45 Fastening element

[0143] 46 Cover element

[0144] 47 Mounting element

[0145] 48 Connection area

[0146] 49 Edge area

[0147] 50 Element

[0148] 51 target wafers

[0149] 52 lasers

[0150] 53 electromagnetic laser radiation

[0151] 54 convoluted sensor

[0152] 55 Main area of ​​the target wafer

[0153] 56 lower main surface of the wafer

[0154] 57 upper main surface of the wafer

[0155] B section

[0156] G F Gravitational force

[0157] D distance

[0158] R H horizontal direction R H

[0159] RI, R2, R3, R4 confocal reflex

Claims

Patent claims 1. Device comprising: - an annular holder (1) and a wafer (3) which is attached in an opening (2) of the annular holder (1), wherein - the wafer (3) has a large number of micro-components (11), - the ring-shaped holder (1) is designed to be connected to a transfer system (40), and - the transfer system (40) is set up to transfer the micro-components (11) from the wafer (3) to another element (50).

2. Device according to the previous claim, wherein the micro-components (11) are micro-LEDs (12).

3. Device according to the previous claim, wherein the wafer (3) is fixed in the opening (2) of the annular holder (1) with an adhesive (4).

4. Device according to one of the preceding claims, wherein the annular holder (1) has a foot (34) on which a first chamfer (36) of an edge (30) of the wafer (3) rests.

5. Device according to one of the preceding claims, wherein the edge (30) of the wafer (3) has a second chamfer (41).

6. Device according to one of the preceding claims, wherein the annular holder (1) has a slope (39) on an outer surface (38).

7. Device according to one of the preceding claims, wherein the wafer (3) is clamped in the annular holder (1).

8. Device according to one of the preceding claims, wherein the annular holder (1) has two sections (44) which are mechanically stably connected to each other by means of an adhesive (4) and / or a fastening element (45).

9. Device according to one of the preceding claims, wherein - the ring-shaped holder (1) has at least three cover elements (46) that partially cover the wafer (3), and - the cover elements (46) are mechanically stably connected to the wafer (3) with an adhesive (4).

10. Device according to one of the preceding claims, wherein a lower main surface (56) of the wafer (3) is flush with the annular holder (1).

11. Wafer (3) comprising a plurality of micro-components (11) and at least three connection areas (48) which are arranged for mechanically stable connection with a transfer system (40), wherein the connection areas (48) are arranged on an edge (30) of the wafer (3).

12. Wafer (3) according to the previous claim, wherein at least one of the connection area (48) has a first chamfer (36) and a second chamfer (41) at the edge (30) of the wafer (3).

13. Wafer (3) according to one of claims 11 to 12, wherein the micro-components (11) are attached to a carrier wafer (9) by means of retaining structures (21).

14. Wafer (3) according to one of claims 11 to 13, wherein the micro-components (11) are attached to the carrier wafer (9) by means of a mounting layer (22).

15. Wafer (3) according to one of claims 11 to 14, wherein a material of the holding structures (21) and / or a material of the assembly layer (22) is configured to be released by irradiation with electromagnetic laser radiation (53).

16. Wafer (3) according to one of claims 11 to 15, comprising at least three measuring areas (7) which are free of micro-components (11) .

17. Method for manufacturing an electronic component comprising the following step: Transfer of a micro-component (11) from a device according to one of claims 1 to 10 and / or from a wafer (3) according to claims 11 to 16 to a further element (50) .

18. Method according to the previous claim, wherein the transfer takes place using a laser (52).

19. Method according to one of claims 17 to 18, wherein - the further element (50) is a target wafer (51) arranged parallel to the wafer (3), and - a distance (D) between the wafer (3) and the target wafer (51) is between inclusive 50 micrometers and inclusive 150 micrometers.

20. Method according to one of claims 17 to 19, wherein a tilt of the wafer (3) relative to the target wafer (51) is determined and corrected before the transfer of the micro-component (11).

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