DEVICE, WAFER AND METHOD FOR MANUFACTURING AN ELECTRONIC COMPONENT

Abstract

A device is specified. The device includes the following features: - 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). Furthermore, a wafer and a method for manufacturing an electronic component are specified.

Description

[0001] A device, a wafer, and a method for manufacturing an electronic component are described.

[0002] 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. Furthermore, an improved wafer is to be specified, from which micro-components are transferred to another element, particularly using a simplified method.

[0003] 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.

[0004] 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.

[0005] Advantageous embodiments and further developments of the device, the wafer and the method are the subject of the dependent claims.

[0006] 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 extent plane. Preferably, the wafer is secured in the opening of the annular holder such that the principal extent plane of the wafer and the principal extent 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.

[0007] For example, the 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. Most 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.

[0008] For example, the ring-shaped holder may be made of one of the following materials: metal, ceramic, plastic, quartz glass, or sapphire. The metal could be aluminum or steel.

[0009] According to a further embodiment of the device, the wafer comprises a plurality 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 zone 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"), then the active area comprises at least one electronic component of a circuit, such as a diode, a transistor, a voltage regulator, a rectifier, and / or an electrical resistor. In the case of a micro-IC, the active area is, for example, enclosed by a single-crystal silicon layer.

[0010] 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 therefore lies, for example, between 1.5 micrometers and 25 micrometers.

[0011] The micro-component is characterized in particular by its exceptionally small dimensions. For example, the edge length of a micro-component, viewed from above in 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 non-destructively removable holding structures. Besides the term micro-component, the following notations can also be used, for example: µ-component, µ-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 phosphor for wavelength conversion. The phosphor is, for instance, part of a wavelength-converting layer within the micro-converter. In particular, the phosphor could be a quantum dot phosphor.

[0015] According to another embodiment, the wafer has a plurality 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 a further 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 for transferring the micro-components includes a laser, a punch, and / or a heating device.

[0017] According to one embodiment, the device comprises the annular holder and the wafer, which is secured in the opening of the annular holder. Furthermore, the wafer contains the plurality of micro-components, and the annular holder is configured to be connected 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 involves using a ring-shaped holder to secure the wafer in the transfer system. This allows for precise alignment and close positioning of the 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, maximizing surface utilization. Additionally, the use of this holder allows for the processing of wafers of varying sizes within the same transfer system, as the wafer's surface area can be adjusted to the system's dimensions. In particular, this approach eliminates the need for a film, which is required for transferring micro-components 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 (LED) with particularly small dimensions. Generally, a micro-LED is not a laser that generates electromagnetic laser radiation through stimulated emission.

[0021] As a rule – this is also a very important criterion in addition to 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 may 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.

[0023] For example, for rectangular micro-LEDs, 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, especially when viewed from above the active zone.

[0024] Most of these micro-LEDs are provided on carrier wafers with holding structures that can be removed without damaging the micro-LED.

[0025] Currently, the primary applications for micro-LEDs are 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 applications such as small monolithic displays for augmented reality (AR) applications, particularly smart glasses. Further applications are also being developed, especially in data communication and pixelated lighting applications.

[0026] In the literature you will find various spellings for “micro-LED”, e.g. µLED, µ-LED, uLED, u-LED or Micro Light Emitting Diode.

[0027] 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 metallurgical bond 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.

[0028] According to a further 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. Alternatively, the edge of the wafer can be straight or rounded without a chamfer. The first chamfer of the wafer edge 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.

[0029] The first chamfer of the wafer edge rests, in particular, on a foot of the ring-shaped holder. Specifically, the foot has an inclined outer surface on which the chamfer of the wafer edge rests in direct contact and preferably over its entire surface. The ring-shaped holder is designed to be inserted into the transfer system with its foot facing downwards along a direction of gravity. In this way, the foot contributes to fixing the wafer in the transfer system. The foot forms, in particular, a projection of the ring-shaped holder that extends into the opening of the ring-shaped holder. For example, the foot extends along the entire opening of the wafer.

[0030] For example, in this embodiment of the device, the edge of the wafer is further mechanically fastened to a second main surface, which faces away from the first chamfer of the wafer's edge, by means of an adhesive. The adhesive, which additionally provides a stable mechanical connection between the wafer and the annular holder, can also be applied selectively or completely circumferentially, as seen from a top view of the device. For example, in this embodiment, the adhesive is at least partially arranged between the annular holder and the edge of the wafer.

[0031] According to a further 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.

[0032] According to a further embodiment, the ring-shaped holder has a slope on one outer surface. This slope is specifically designed to secure the device in the transfer system. For example, the slope on the outer surface runs parallel to a sloping support surface of the base. In particular, the slope is intended to be installed in the transfer system facing downwards along the direction of gravity.

[0033] According to a further embodiment of the device, the wafer is clamped in the annular holder. In particular, the wafer is not attached to the annular holder with an adhesive or other joining element, but is in direct contact with the annular holder. In this embodiment, the wafer preferably has a first chamfer and a second chamfer extending from two opposing main surfaces of the wafer, such that the edge of the wafer has two inclined, converging surfaces. In this embodiment, the annular holder preferably also has two inclined surfaces at its opening, on which the first chamfer and the second chamfer of the wafer's edge rest.

[0034] According to a further embodiment, the ring-shaped holder has at least two sections that are mechanically and stably connected to each other by an adhesive and / or a fastening element. In particular, this embodiment of the ring-shaped holder is designed in conjunction with a clamped connection between the wafer and the ring-shaped holder. For example, a screw or a clamp can be used as the fastening element. In particular, the fastening element is designed to allow the two sections of the ring-shaped holder to be separated from each other without damage.

[0035] According to a further embodiment of the device, the annular holder has at least three cover elements that partially cover the wafer. In this embodiment, 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 the 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 microcomponents due to the wafer's fixation in the annular holder. For example, the cover elements are designed as projections with a semicircular base.

[0036] According to a further 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 such that it faces 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.

[0037] 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 to install the wafer 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 herein in connection with the device can also be implemented in the wafer alone, and vice versa.

[0038] According to one embodiment, the wafer comprises a plurality of micro-components and at least three connection areas configured for a mechanically stable connection to a transfer system. In particular, the connection areas are arranged along an edge of the wafer. The micro-components can be identical or different from one another. Preferably, at least one central area of ​​the wafer is completely covered with micro-components. Likewise, an edge 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 preferably designed to be separate from one another and are separated, for example, by portions of the edge area that are covered with micro-components.

[0039] According to a further 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 forming the connection areas, so that the wafer is configured to be installed in the transfer system at these locations. For this purpose, the transfer system has, 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.

[0040] According to another embodiment of the wafer, 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, for example, made of or comprise 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 comprises the same material as the retention structures or is made of the same material as the retention structures.

[0041] 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 instance, formed across the entire area between the support wafer and the micro-components. Specifically, recesses, which may be air-filled, are arranged between the assembly layer and the micro-components. Furthermore, the polymer layer structure may include 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.

[0042] According to another embodiment of the wafer, 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. In particular, there are no recesses between the mounting layer of the polymer layer structure and the micro-components.

[0043] According to another embodiment of the wafer, a material of the holding 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 holding structures and / or the material of the assembly layer is BCB or a polyimide.

[0044] According to a further embodiment, the wafer comprises at least three measuring areas that are free of micro-components. The measuring areas are specifically configured for distance measurement and / or tilt measurement, particularly using 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.

[0045] The measuring areas are typically located at the edge of the wafer. For example, the measuring areas of the wafer may consist solely of portions of the support wafer. Furthermore, it is also possible that only a single mounting layer of the polymer layer structure is present in the measuring area. Alternatively, the polymer layer structure in the measuring area may be identical to that in the rest of the wafer and may include, in addition to the mounting layer, retaining structures and / or separating elements.

[0046] The device and the wafer are specifically designed for use in a method 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 method, and vice versa.

[0047] According to one embodiment of the method, a micro-component is transferred from a device and / or a wafer to another element. In particular, the method involves the successive transfer of several micro-components from the device and / or the wafer to the other element.

[0048] 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.

[0049] 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.

[0050] According to one embodiment of the method, the transfer of the micro-components to the further element takes place using a laser. For example, holding structures and / or a mounting layer and / or other parts of a polymeric layer structure are at least partially dissolved using the laser, so that a pulse is transmitted to the micro-component to be transferred, causing it to detach from the wafer and, in particular, from the polymeric layer structure and be transferred to the further element.

[0051] 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 embodiment of the method, the micro-components are connected to the carrier wafer, in particular by retaining structures, which are broken open by the stamp. Another possibility is to expand a gas, for example air, located in a recess 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.

[0052] According to a further 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.

[0053] According to a further embodiment of the method, a tilt of the wafer relative to the target wafer is determined and, in particular, corrected. Here, measuring areas of the wafer are used in particular, where a tilt of the wafer relative to the target wafer is determined, for example, using a conical sensor.

[0054] The present method can be used in particular to produce electronic components with micro-LEDs as active elements. Such electronic components can be, for example, transparent and opaque symbols and characters, as well as luminous films.

[0055] 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 electronics. These electronic components can also be found in ambient lighting, RGB displays, headlights, displays, and projectors.

[0056] 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. The Fig. 1 and Fig. Figure 2 shows schematic views of a device according to an exemplary embodiment. The Fig. 3 and Fig. Figure 4 shows schematic sectional views of a wafer according to two embodiments. The Fig. 5 and Fig. Figure 6 shows schematic views of a wafer according to a further embodiment. The Fig. Figure 7 shows a schematic sectional view of a wafer according to a further embodiment. The Fig. Figures 8 to 13 show schematic sectional views of a device according to various embodiments. The Fig. 14 and Fig. Figure 15 shows schematic views of a device according to a further embodiment. The Fig. 16 and Fig. Figure 17 shows schematic views of a wafer in a transfer system according to an exemplary embodiment. The Fig. Figure 18 shows a schematic representation of a stage of a process according to an exemplary embodiment. The Fig. 19 and Fig. Figure 20 shows schematic representations of a device according to an exemplary embodiment. The Fig. 21, Fig. 22 and Fig. Figure 23 schematically shows measurements of a wafer tilt according to various embodiments.

[0057] 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.

[0058] The device according to the exemplary embodiment of the Fig. 1 and Fig. 2 has a ring-shaped holder 1 with an opening 2. Fig. Figure 2 shows a sectional view of the device according to the Fig. 1 along the intersection line AA.

[0059] A wafer 3 is fixed in the opening 2 of the annular holder 1 using an adhesive 4. Specifically, the wafer 3 is mechanically stable in the opening 2 of the annular holder 1 due to the adhesive 4. The adhesive 4 is applied 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.

[0060] 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. Furthermore, the wafer 3 has three measuring areas 7, which are configured for tilt measurement ( Fig. 1).

[0061] 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 plurality 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 described below with reference to the Fig. 3 to 7 explained in more detail, which are in Fig. 2. Show in more detail the section of wafer 3 labelled B.

[0062] The wafer 3 according to the embodiment of the Fig. Wafer 3 has a carrier wafer 9. Furthermore, wafer 3 comprises micro-components 11, which in this case are designed as micro-LEDs 12.

[0063] 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, directing 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, 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.

[0064] The wafer 3 according to the embodiment of the Fig. 3 further features a polymeric layer structure 20 with holding structures 21, an assembly layer 22 and separating elements 23.

[0065] The mounting layer 22 is fully and materially 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.

[0066] The wafer 3 according to the embodiment of the Fig. 4 differs from the wafer according to the embodiment of the Fig. 3 in the design of the polymeric layer structure 20. In particular, the polymeric layer structure 20 has no holding 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 polymeric layer structure 20.

[0067] The wafer 3 according to the embodiment of the Fig. 5 and Fig. In contrast to wafer 3 according to the embodiment of the Fig. Four recesses 24 are located between the polymer layer structure 20 and the micro-LEDs 12. The recesses 24 are, for example, air-filled ( Fig. 5). Fig. Figure 6 shows a top view of wafer 3 according to the Fig. 5.

[0068] Furthermore, the wafer 3 has a fully applied bonding layer 25 that mechanically connects the micro-LEDs 12 to separating elements 23 of a polymeric layer structure 20. The separating elements 23 form anchors 26 that mechanically connect the bonding layer 25 to the carrier wafer 9. In the area of ​​the separating elements 23, the bonding layer 25 forms retaining straps 27, which are primarily strip-shaped and span the recesses 24. Fig. 6) The compound layer 25, for example, comprises or consists of a metal, oxide, or nitride such as SiNx. In this case, the compound layer 25 replaces the passivation layer 19 and performs its function in the micro-LEDs 12.

[0069] The wafer 3 according to the embodiment of the Fig. In contrast to wafer 3 according to the exemplary embodiment of the Fig. 5 and Fig. 6 A sacrificial layer 28 is 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.

[0070] The Fig. Figures 8 to 13 show sections of a device with an annular holder 1 and a wafer 3, which is attached in an opening 2 of the annular holder 1. In particular, the figures shown illustrate the connection between the annular holder 1 and the wafer 3.

[0071] In the device according to the exemplary embodiment of the Fig. In section 8, the wafer 3 is attached to the annular holder 1 by means of an adhesive 4. Specifically, the adhesive 4 is located in and completely fills a gap 29 between the annular holder 1 and an edge 30 of the wafer 3. The adhesive 4 forms a meniscus 33 on a second main surface 31 of the wafer 3, which is opposite a first main surface 32 of the wafer 3. 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.

[0072] In the device according to the exemplary embodiment of the Fig. 9 The annular holder 1 has a foot 34 with an inclined contact surface 35. Furthermore, the wafer 3 has a first chamfer 36 of an edge 30. The first chamfer 36 has an inclined partial surface 37 that extends 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 contact surface 35 of the foot 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.

[0073] The device according to the exemplary embodiment of the Fig. 10, unlike the device according to the exemplary embodiment of the Fig. 9 a ring-shaped 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 ring-shaped holder 1 is directed downwards in the direction of a gravitational force G to secure the ring-shaped holder 1 in a transfer system 40. F provided (compare) Fig. 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.

[0074] The device according to the exemplary embodiment of the Fig. 11, unlike the device of Fig. 9 a wafer 3 with a second chamfer 41 on 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 has according to Fig. 11 two chamfers 36, 41 which are formed on an edge 30 of the wafer 3.

[0075] 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 results in particularly good anchoring of the wafer 3 in the opening 2 of the annular holder 1.

[0076] In the devices according to the exemplary embodiments of the Fig. 12 and Fig. In contrast to the devices according to embodiments 8 to 11, the wafer 3 is mechanically fixed in the opening 2 of the ring-shaped holder 1 by a clamp and not by an adhesive 4.

[0077] The devices of Fig. 12 and Fig. Figure 13 comprises a wafer 3 whose edge 30 has a first chamfer 36 and a second chamfer 41. Both chamfers 36 and 41 extend from a main surface 31 and 32 of the wafer 3, respectively, 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 and 41.

[0078] Furthermore, the ring-shaped holder 1 of the device according to the exemplary embodiment of the Fig. 12 two sections 44 which are symmetrically formed and mechanically stably connected with an adhesive 4.

[0079] The device according to the exemplary embodiment of the Fig. 13, unlike the device according to Fig. 12 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.

[0080] The device according to the exemplary embodiment of the Fig. 14 and Fig. 15 has a ring-shaped holder 1 with cover elements 46, which partially extend over a second main surface 31 of the wafer 3 and are mechanically stable connected to it only in the area of ​​the cover elements 46 by an adhesive 4. Fig. Figure 14 shows a top view of the device and Fig. 15 a section of a sectional view in the area of ​​a cover element 46.

[0081] Fig. 16 and Fig. Figure 17 shows 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.

[0082] The wafer 3 has, in particular, four connection areas 48, which are arranged opposite each other at the edge 30 of the wafer 3. Each connection area 48 has a first chamfer 36 and a second chamfer 41, as shown in Fig. Figure 17 shows that the edge 30 of the wafer 3 is formed without a chamfer between the connection areas 48. 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.

[0083] Fig. 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.

[0084] In the procedure according to the Fig. 18. A device such as that shown, for example, in the Fig. 1 and Fig. As already described in section 2, the wafer 3 is placed into a transfer system 40. Wafer 3, for example, is designed as shown in the... Fig. 3 described.

[0085] Furthermore, transfer system 40 contains an element 50 onto which at least one micro-LED 12 from wafer 3 is transferred using the process. This element 50 is a target wafer 51, which is also mechanically stable mounted in 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.

[0086] 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 onto the target wafer 51.

[0087] The laser 52 is directed in a horizontal direction R. H The micro-LEDs 12 are moved across wafer 3, transferring them successively to the target wafer 51 in subsequent steps. In these subsequent steps, several micro-LEDs 12 are transferred to the target wafer 51 in a freely programmable pattern.

[0088] To ensure the most error-free electronic components possible in the method according to the exemplary embodiment of the Fig. To obtain 18, it is advantageous, due to the small distance D between the device and the target wafer 51, that they are arranged as parallel to each other as possible. Based on the Fig. Therefore, in sections 19 to 23, methods for determining a tilting of the wafer 3 in the ring-shaped holder 1 are described in more detail.

[0089] The Fig. 19 and Fig. Figure 20 shows schematic representations of a device with a wafer 3, the tilt of which is determined relative to a target wafer 51. The device is configured, for example, as shown in the Fig. 1 and Fig. 2 already described. In particular, wafer 3 has three measuring areas 7. One measuring area 7 is separated from section B of the Fig. 19 and Fig. 20 included and in the Fig. 21, Fig. 22 and Fig. 23 shown in detail.

[0090] Fig. Figure 21 shows a schematic cross-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 shown in the Fig. 18 described.

[0091] In the case of wafer 3 according to the embodiment of the Fig. In measuring area 7, the micro-components 11 have been removed, leaving only the polymer layer structure 20 with an assembly layer 22, retaining structures 21, and separating elements 23 on the carrier wafer 9. The remaining wafer 3 is formed as already shown in the Fig. 3 described.

[0092] For tilt measurement, a confocal sensor 54 is used, which generates two different confocal reflections R1 and R2 within the measuring range. The confocal sensor 54 is also enclosed by the transfer unit 40. A first confocal reflection R1 is generated on an outer surface 10 of the carrier wafer 9, and a second confocal reflection R2 is generated on the polymer layer structure 20. Finally, a third confocal reflection R3 is generated on a main surface 55 of the target wafer 51, which faces the wafer 3. From the three confocal reflections R1, 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 the 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.

[0093] In the embodiment according to the Fig. 22 is in measuring range 7, unlike the embodiment of the Fig. 21 a material of the polymeric layer structure 20 applied in an unstructured manner, so that it is flush with a radiation emission surface 16 of the micro-LEDs 12.

[0094] In this embodiment, a fourth confocal reflection R4 is additionally generated on an outer surface of the material of the polymer layer structure 20 during distance measurement.

[0095] In the embodiment according to the Fig. 23 The polymer layer structure 20 is completely removed in the measuring area 7. A first confocal reflection R1 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 invention is not limited to the description provided by means of 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 claims, even if that feature or combination itself is not explicitly stated in the claims or exemplary embodiments. Reference symbol list 1 ring-shaped holder 2 openings 3 wafers 4 Adhesive 5 Positioning element 6 Notch of the wafer 7 Measuring range 8 functional layers 9 carrier wafers 10 Outer surface of the carrier wafer 11 micro-component 12 micro-LEDs 13 epitaxial semiconductor layer sequence 14 active zones 15 metal mirrors 16 Radiation emission surface 17 electrical contact 18 Passivation 19 Passivation layer 20 polymer layer structure 21 Support structure 22 Assembly layer 23 Separating element 24 Exclusion 25 Compound layer 26 anchors 27 Restraint strap 28 Victim class 29 gap 30 Edge of the wafer 31 second main surface of the wafer 32 first main surface of the wafer 33 Meniscus 34 feet 35 inclined support surface 36 first phase 37 inclined partial surface 38 Outer surface of the ring-shaped holder 39 Slanted 40 Transfer facility 41 second phase 42 cavities 43 Inner surface of the ring-shaped holder 44 sections 45 Fastening element 46 Cover element 47 Mounting element 48 Connection area 49 Edge area 50 Element 51 target wafers 52 lasers 53 electromagnetic laser radiation 54 convoluted sensor 55 Main area of ​​the target wafer 56 lower main surface of the wafer 57 upper main surface of the wafer B section G F Gravitational force D distance R H horizontal direction R H R1, R2, R3, R4 confocal reflex

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 any 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 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 support wafer (9) by means of retaining structures (21). [14] Wafer (3) according to any 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 any 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 any 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: Transferring 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 any 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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