Method and apparatus for releasing an adhesive base structure for detaching an electronic component

Abstract

A method comprising: • Mounting a plurality of electronic components (100) on associated parts of an adhesive base structure (102) on a temporary carrier (112, 112'); and • Detaching the parts of the base structure (102) by irradiating the parts of the base structure (102) with electromagnetic radiation (104) in order to thereby detach the electronic components (100); • Transferring the electronic components (100) to and batch soldering the electronic components (100) onto one or more permanent supports (108).

Description

Background of the inventionField of the invention

[0001] The present invention relates to a method and an apparatus. Description of the state of the art

[0002] Packages can be encapsulated electronic chips with electrical connections extending from the encapsulation and connectable to an electronic peripheral. Before packaging, a semiconductor wafer is separated into a plurality of electronic chips. After the wafer is separated into the separate electronic chips, the electronic chips of the wafer can be picked up and placed at a target.

[0003] US 2005 / 0 164 472 A1 discloses a method for singulating thin chips from a sawn wafer. In this method, the chips are arranged on a glass plate using an adhesive film. To pick up the chips individually from the glass plate using a vacuum pipette, corresponding areas of the adhesive film are irradiated with a radiation source, for example, through the glass plate. This heats the adhesive film, causing it to lose its adhesive properties, allowing the chips to be picked up using the vacuum pipette.

[0004] EP 3 742 477 A1 discloses a method for transferring components between different substrates. A second substrate with an adhesive layer is pressed onto the components, which are initially arranged on a first substrate. Heat is then applied, for example by radiation, to cure the adhesive layer, thereby firmly bonding the components to the second substrate. Subsequently, the components are transferred to a third substrate by selectively irradiating corresponding areas of the adhesive layer with light, thereby locally melting the adhesive layer. As a result, threads of molten adhesive material are formed, which are intended to slow the falling of the components.

[0005] JP 2010-56213 A discloses a method for mounting a semiconductor device on a mounting element. In the method, a semiconductor substrate is attached to an adhesive carrier material, and then the semiconductor substrate is singulated. To transfer the singulated semiconductor devices from the carrier material to a mounting element, the carrier material is irradiated with UV light, thereby reducing the adhesive force of the carrier material so that it is lower than the adhesive force of a conductive material that attaches the semiconductor device to a surface of the mounting element. The carrier material can then be removed from the electronic device. The carrier material is made, for example, of a UV-curable resin. Summary of the invention

[0006] There may be a need to handle electronic components efficiently.

[0007] According to an exemplary embodiment of a first aspect, a method is provided, the method comprising mounting a plurality of electronic components on associated parts of an adhesive base structure on a temporary carrier, and detaching the parts of the base structure by irradiating the base structure with electromagnetic radiation to thereby detach the electronic component. Furthermore, the method comprises transferring the electronic components to and batch soldering the electronic components onto one or more permanent carriers.

[0008] According to another exemplary embodiment of the first aspect, an apparatus is provided comprising an electromagnetic radiation source configured to irradiate at least one mounting portion of an adhesive base structure on a temporary carrier, on which mounting portion an electronic component is mounted, to thereby detach the electronic component from the mounting portion, and an alignment unit for aligning a mutual position between, on the one hand, a carrier for carrying the electronic component and, on the other hand, the detached electronic component (which, for example, falls downwards by means of gravity), such that the (for example, falling downwards) electronic component is transferred to the carrier and lands thereon. The apparatus is configured for batch soldering a plurality of the electronic components onto one or more permanent carriers.

[0009] According to an exemplary embodiment of a second aspect, an apparatus is provided which comprises an electromagnetic radiation source which is configured to irradiate at least one mounting portion of an adhesive base structure, on which mounting portion an electronic component is mounted, in order to thereby detach the electronic component from the mounting portion, and a pick-and-place unit which is configured, after detachment, to pick up the electronic component on one side by means of a picking tool, then to further pick up the electronic component on an opposite other side by means of another picking tool, and subsequently to place the electronic component with the one side on a carrier.

[0010] According to an exemplary embodiment of a third aspect, an apparatus is provided which comprises a fastening unit configured to fasten a preform of the electronic component on one side to a temporary carrier during the manufacture of the electronic component, a further fastening unit configured to fasten the electronic component on an opposite other side to a further temporary carrier, an electromagnetic radiation source configured to irradiate at least one mounting portion on which the electronic component is mounted, an adhesive base structure arranged between the further temporary carrier and the electronic component to thereby detach the electronic component from the mounting portion, and a pick-and-place unit configured toAfter detaching, pick up the electronic component on one side using a picking tool and then place the electronic component on a carrier.

[0011] According to an exemplary embodiment of a fourth aspect, a method is provided which comprises irradiating at least a portion of an adhesive base structure on a temporary carrier with electromagnetic radiation to thereby detach a plurality of electronic components from the base structure, to transfer the electronic components to another carrier having a changed pitch, and subsequently transferring the electronic components to and batch-connecting (preferably batch-soldering) the electronic components to one or more permanent carriers according to the changed pitch.

[0012] According to an exemplary embodiment of the fourth aspect, an apparatus is provided comprising an electromagnetic radiation source configured to irradiate an adhesive base structure on a temporary carrier on which a plurality of electronic components are mounted, in order to thereby detach the electronic components from the base structure, and an alignment unit configured to align a mutual position between, on the one hand, a further carrier for carrying the electronic components and, on the other hand, the detached electronic components, in order to transfer the electronic components to the further carrier with the changed (for example, increased) pitch, wherein the alignment unit can optionally be further configured to align the further carrier with one or more permanent carriers,for subsequently transferring the electronic components to and connecting (in particular by soldering, preferably by diffusion soldering) the electronic components to the one or more permanent supports in accordance with the changed pitch.,

[0013] According to an exemplary embodiment of the first aspect, an electronic component mounted on an adhesive base structure can be detached therefrom by dissolving material of the base structure using electromagnetic radiation. The detachment of the electronic component from the previously adhesive base structure can be performed in an aligned manner between the electronic component and the carrier, such that the detached electronic component is transferred to the carrier (e.g., falling under gravity or transferred in another manner, e.g., using gas pressure) and lands thereon, where it can rest or be permanently bonded.

[0014] Advantageously, the detachment of an electronic component from a previously adhesive base structure can be triggered by at least partially detaching the adhesive material, so that the adhesive force is weakened or eliminated, causing the electronic component to be transferred (e.g., falling downwards or transferred by means of gas pressure). Positioning a carrier at a predicted landing position of the, for example, falling downwards or otherwise transferred electronic component can make it possible to mount the electronic component on the carrier in a very simple and reliable manner. Consequently, it can be possible to handle electronic components efficiently. In particular, the detachment of a chip from a dicing tape can be accomplished without needling from the backside, which can avoid conventional disadvantages associated with die knocking, i.e.A lateral contact of adjacent electronic components that have already been separated from a wafer assembly and are individually detached by means of a needle-lifting of each electronic component from the back. By replacing such a conventional approach with a laser-assisted process of dissolving an adhesive base structure, the risk of damage to the electronic component and the detachment effort can be significantly reduced.

[0015] According to an exemplary embodiment of the second aspect, an adhesive base structure with a mounted electronic component is selectively irradiated with electromagnetic radiation to trigger detachment of the electronic component from the adhesive base structure. This can enable a pick-and-place unit to pick up the detached electronic component on one side and further pick up the picked-up electronic component on an opposite side for placing the electronic component on a carrier.Selectively irradiating an adhesive base structure with electromagnetic radiation can cause a loss of adhesive retention force, which can allow a pick-and-place unit, which has at least two pick-up tools for handling the electronic component on either side, to place it with a desired main surface facing a target carrier or other surface. This architecture can enable the electronic component to be mounted on a carrier or similar device in a very simple and reliable manner and to handle the electronic components efficiently.

[0016] According to an exemplary embodiment of the third aspect, a preform of an electronic component is attached to a temporary carrier on one side. Furthermore, the electronic component can be attached to another temporary carrier on an opposite other side, and the first temporary carrier can be removed. By irradiating an adhesive base structure between the further temporary carrier and the electronic component with electromagnetic radiation, the electronic component can be detached from the adhesive base structure. This can then make it possible to pick up the electronic component and place it on a target carrier. Such an approach can make it possible to mount the electronic component on the carrier in a very simple and reliable manner and to handle the electronic components efficiently.

[0017] According to an exemplary embodiment of the fourth aspect, an adhesive base structure on a temporary carrier carrying a plurality of electronic components can be exposed to electromagnetic radiation to detach the electronic components from the base structure. This allows them to be transferred from the temporary carrier to a further carrier (e.g., a heat-resistant carrier, such as a metal plate, with an adhesive surface) with a modified (preferably enlarged) pitch compared to a pitch of the electronic components on the temporary carrier. Thereafter, the electronic components can be transferred from the further carrier (from which they can be detached) to one or more permanent carriers (such as, for example, a lead frame with lead frame structures) in accordance with the modified pitch. By means of simultaneous connection (e.g., by means of batch soldering, i.e.By soldering the electronic components together (a common soldering process), they can be firmly bonded to the permanent carrier or carriers. The additional carrier can be removed from the resulting packages. Such a process can be extremely efficient and can also involve transferring the pitch corresponding to one wafer level to another pitch corresponding to a lead frame level or similar, and can be fully compatible with batch diffusion soldering.

[0018] The first, second, third and / or fourth aspects may be realized individually or in any combination. Description of further exemplary embodiments

[0019] Further exemplary embodiments of the methods and apparatus are explained below.

[0020] In the context of the present application, the term "electronic component" may in particular encompass a semiconductor chip (in particular a power semiconductor chip), an active electronic device (for example, a transistor), a passive electronic device (for example, a capacitance or an inductance or an ohmic resistance), a sensor (for example, a microphone, a light sensor, or a gas sensor), an actuator (for example, a loudspeaker), and a microelectromechanical system (MEMS). However, in other embodiments, the electronic component may also be of a different type, for example, a mechatronic element, in particular a mechanical switch, etc. In particular, the electronic component may be a semiconductor chip having at least one integrated circuit element (for example, a diode or a transistor) in a surface portion thereof.The electronic component may be a bare die or may be pre-packaged or encapsulated. Semiconductor chips implemented according to exemplary embodiments may be formed using silicon technology, gallium nitride technology, silicon carbide technology, etc.

[0021] In the context of the present application, the term "electronic component preform" may, in particular, refer to a semi-finished product that already has some functionality, but not yet all of the functionality, of a fully manufactured electronic component. For example, an electronic component preform may still form part of a wafer assembly before being separated therefrom. It is also possible that an electronic component preform may still lack a structural feature of a fully manufactured electronic component, such as all or part of the pads necessary for it to be operational.

[0022] In the context of the present application, the term "carrier" (which may also be referred to as "electronic component carrier") may in particular refer to a support structure (which may be at least partially electrically conductive) which serves as a mechanical support for the electronic component(s) to be mounted thereon and which may also contribute to the electrical connection between the electronic component(s) and the periphery of the package. In other words, the carrier may fulfill a mechanical support function and an electrical connection function. Such a carrier may be a permanent carrier, i.e., may form part of a finished package (see, for example, Fig. 1). A carrier may comprise or consist of a single part, multiple parts connected via an encapsulation or other package components, or a subassembly of carriers. If the carrier forms part of a lead frame, it may also be or comprise a die pad. However, such a carrier may also be a temporary carrier, i.e., it may be removed before completing the manufacture of a package (see, for example, Fig. 18).

[0023] In the context of the present application, the term "temporary support" may in particular refer to a support structure, which is shaped, for example, as a plate or a tape, which is to be attached to an electronic component or a preform thereof only during part of a manufacturing process and which is to be removed from the electronic component or its preform before completion of the manufacturing process.

[0024] In the context of the present application, the term "adhesive base structure" may, in particular, refer to a sticky physical structure configured to temporarily adhere to an electronic component, for holding the electronic component, e.g., on a temporary support, by means of an adhesive force. For example, the adhesive base structure may be an adhesive base layer, which may, for example, be continuous or patterned.

[0025] In the context of the present application, the term “mounting section of the adhesive base structure” may in particular refer to a subsection of an adhesive base structure on which subsection an electronic component is mounted with direct physical contact.

[0026] In the context of the present application, the term "dissolving at least a portion of the base structure" may, in particular, refer to dissolving or removing a material of the base structure. For example, dissolving the base structure may be embodied as converting the material of the base structure from a solid phase to a gaseous phase. It is also possible for a base structure to be dissolved by vaporizing or burning it. For example, an adhesive base structure that is dissolved may be embodied as a UV-sensitive adhesive comprising triazene. Such an adhesive can be converted exclusively into gaseous components (in particular carbon dioxide, water vapor, and / or nitrogen gases) by means of UV radiation.

[0027] In the context of the present application, the term "detachment of the electronic component" may specifically refer to triggering a separation of the electronic component, for example, from a temporary support. Such detachment of an electronic component may be triggered by deactivating an adhesive force of a previously adhesive base structure that held the electronic component to a temporary support or other structure. More generally, the detachment of an electronic component from a structure may be accomplished by reducing or eliminating a holding force.

[0028] In the context of the present application, the term "electromagnetic radiation source" may, in particular, refer to an emitter of electromagnetic radiation. An electromagnetic radiation source may be configured to emit electromagnetic radiation of a specific wavelength or range of wavelengths. For example, an electromagnetic radiation source may be configured to emit monochromatic or polychromatic light, for example, in an ultraviolet range, a visible range, and / or an infrared range. For example, a laser may be implemented as the electromagnetic radiation source.

[0029] In the context of the present application, the term "aligning a mutual position between a carrier and an electronic component which is detached and falls downwards by gravity so that the electronic component lands on the carrier" may in particular mean that a suitable spatial relationship between the carrier and the electronic component can be deliberately selected or adjusted so that when the previously attached electronic component loses its holding force, the electronic component falls downwards under gravity and automatically reaches the position of the carrier.In one embodiment, this may be achieved by a static arrangement between a pre-attached electronic component and a carrier, such that releasing a fastening force of the electronic component forces the electronic component to fall vertically downwards onto the carrier arranged vertically below. In another embodiment, this may be achieved by relative movement between the carrier and the pre-attached electronic component, wherein the relative movement and the fall trajectory are coordinated with the positions between the electronic component and the carrier to ensure that the falling electronic component reaches the carrier.

[0030] In the context of the present application, the term "pick-and-place unit" may specifically refer to an assembly configured for picking an electronic component or a preform thereof from an initial position and / or initial orientation and placing it in a different, final position and / or a different final orientation. For example, this may be accomplished by means of vacuum suction or gripping.

[0031] In the context of the present application, the term "pick-and-place unit comprising a picking tool and another picking tool" may specifically refer to a pick-and-place unit having two different picking tools, such as two different vacuum suction elements or two different grippers. For example, one picking tool may pick up the electronic component on one main surface, and the other picking tool may pick up the electronic component on the opposite, other main surface.

[0032] In the context of the present application, the term “pitch” may in particular refer to a center-to-center distance between adjacent electronic components and / or between adjacent functional electronic component sections.

[0033] In embodiments, various detachment strategies for detaching an electronic component from an adhesive base structure can be performed using electromagnetic radiation. First, a desired exposure strategy can be selected, for example, homogeneous exposure, spiral scanning, grayscale lithography, etc. This selection can be made, for example, to achieve minimal impact and sufficient placement accuracy. For example, such a strategy can also be selected in accordance with substrate exchange times, which can be a relevant factor, especially for low-density leadframe applications.

[0034] In one embodiment, the method comprises mounting a plurality of electronic components on associated parts of the adhesive base structure, and detaching the parts of the base structure by irradiating the parts, in order to thereby detach the electronic components by dissolving corresponding sections of the adhesive base structure, in particular simultaneously or sequentially. By selectively irradiating only a single or a group of electronic components with electromagnetic radiation, only the irradiated subgroup of electronic components is selectively detached by dissolving one or more corresponding sections of the adhesive base structure, whereas all remaining non-irradiated electronic components remain adhered to the adhesive base structure. This makes it possible to precisely define one or more electronic components that are to be detached at a time.

[0035] In one embodiment, the method comprises detaching at least a portion of the base structure such that the base structure is converted from a component-bearing solid state into a component-removing dissolved gaseous and / or liquid state. Thus, the aggregate state of the base structure material can be changed—preferably triggered by irradiation with electromagnetic radiation—which causes the adhesive base structure to vanish from an interface between the electronic component and a temporary support. Thus, the detachment process may not only convert the adhesive base structure from an adhesive to a non-adhesive configuration, but may also convert it from a solid to a gaseous or liquid phase, thereby promoting the detachment of an associated electronic component in a precisely definable and rapid manner.

[0036] In one embodiment, the method comprises irradiating the base structure with an electromagnetic radiation source configured as a laser to thereby detach the electronic component. Advantageously, a laser beam may be capable of applying a large amount of energy in a short time to a spatially precisely definable portion of the adhesive base structure. Furthermore, a laser may have a precisely defined wavelength, which may be set to a value at which laser-triggered dissolution of the base structure material is efficient or works best. Consequently, a laser may be a preferred choice for an electromagnetic radiation source that triggers the dissolution of the adhesive base structure material.

[0037] In one embodiment, the method comprises aligning a mutual position between, on the one hand, a carrier for supporting the electronic component and, on the other hand, the detached electronic component (which, for example, falls downwards due to gravity), such that the detached (e.g., falling downwards) electronic component is transferred to and lands on the carrier. When a temporary carrier having a bottom surface to which an electronic component is adhered by means of an adhesive base structure is subjected to an influence that dissolves the adhesive base structure, the trajectory of the detached (e.g., falling) electronic component is precisely predictable by physical laws.Consequently, a carrier can be arranged at a position directly beneath the previously adhered electronic component to ensure that the (e.g., falling) detached electronic component automatically lands on the carrier. Thus, a die placement process can be triggered by pure spatially selective irradiation in combination with appropriate spatial alignment between the electronic component and the carrier. As a result, the process of mounting an electronic component on the carrier can be significantly simplified compared to conventional approaches. Various embodiments exist for transferring the detached electronic component. As mentioned, the transfer of the detached electronic component can be accomplished by triggering, so that the electronic component falls downwards by gravity.However, in other embodiments, it is also possible for the detached electronic component to be transferred by means of gas pressure, gravity, or an expansion of the base structure (e.g., adhesive) or an intermediate layer. In all of these embodiments, the detached electronic component can be transferred such that the transferred electronic component lands on the receiving carrier. Accordingly, the apparatus can be configured such that the detached electronic component falls downwards by means of gravity, so that the falling electronic component lands on the carrier. Additionally or alternatively, the apparatus can be configured such that the detached electronic component is transferred such that it lands on the carrier by means of gas pressure, gravity, or an expansion of the base structure or an intermediate layer.

[0038] In one embodiment, the method comprises detaching at least a portion of the base structure while the electronic component is disposed on a bottom side of the adhesive base structure. With such a geometry, the electronic component automatically falls downward under gravity after detachment. No further action is required for a process of mounting the electronic component on the carrier disposed underneath.

[0039] In another embodiment, the method comprises detaching at least a portion of the base structure while the electronic component is disposed on top of the adhesive base structure. In such a configuration, the electronic component does not fall downwards, but is still supported in a now non-adhesive manner on the temporary carrier beneath the electronic component. After detaching a portion of the adhesive base structure therebetween, the electronic component is thus now in a configuration in which it can be freely detached from the temporary carrier with a low force. This can be accomplished, for example, by means of a vacuum suction tool or by means of a mechanical gripper.

[0040] In one embodiment, the method comprises, after detachment, picking up the electronic component on one side thereof using a picking tool, in particular a suction-type picking tool, and subsequently placing the picked-up electronic component on a carrier. For example, the side of the electronic component that was previously attached to the now-detachable adhesive base structure can be bonded to a target surface, for example, a carrier.

[0041] In one embodiment, the method comprises, after picking up (for example, by means of a first picking tool), a further picking up (for example, by means of a second picking tool) of the electronic component on an opposite other side thereof by means of another picking tool, in particular another suction-type picking tool, and subsequently placing the electronic component with one side on the carrier. For certain applications, it may be desired that a target main surface of the electronic component, which faces away from another main surface on the now dissolved adhesive base structure, is brought into direct physical contact with a target surface, for example, a carrier. To achieve this, two picking tools can cooperate accordingly.A first pick-up tool can pick up the electronic component from the temporary carrier at its target main surface after the previously adhesive base structure has been dissolved. A second pick-up tool can then pick up the picked electronic component at the other main surface, thereby exposing it at its target main surface. The second pick-up tool can then attach the electronic component with its target main surface to a target surface, for example, a carrier.

[0042] In another embodiment, the method comprises, prior to picking, attaching the electronic component on an opposite other side to a temporary carrier, and after picking, placing the picked electronic component with the other side on the permanent carrier. For example, it may be possible to implement an additional temporary carrier on which an electronic component can be placed to expose a target main surface thereof for subsequent connection to a target surface, e.g., a carrier. Advantageously, such reassembly using two temporary carriers may eliminate the need for a second picking tool.

[0043] In one embodiment, the method comprises detaching at least a portion of the base structure by irradiating it with electromagnetic radiation, thereby detaching a plurality of electronic components, in order to transfer the plurality of electronic components to another carrier with a modified, for example, enlarged, pitch compared to another pitch of the plurality of electronic components on the temporary carrier. Accordingly, the apparatus can be configured to control the irradiation of at least the mounting portion of the adhesive base structure with electromagnetic radiation, thereby detaching a plurality of electronic components from the mounting portion, in order to transfer the plurality of electronic components to the carrier with the modified, in particular enlarged, pitch compared to another pitch of the plurality of electronic components on the temporary carrier.Advantageously, the described transfer may adjust a pitch (i.e., mutual center-to-center distances between adjacent electronic components or corresponding functional portions thereof) between the electronic components as they are separated from a common wafer and the electronic components to be mounted on a permanent carrier (e.g., a corresponding leadframe structure).

[0044] In one embodiment, the further carrier is a further temporary carrier. Preferably, the further carrier is a high-temperature-resistant carrier, for example, temperature-resistant up to at least 220°C. For this purpose, the further carrier can be a metal carrier. Thus, the further carrier can be a temperature-resistant carrier (for example, a metal plate) that can withstand subsequent high-temperature processing, for example, by diffusion soldering of the electronic components onto the one or more permanent carriers. The further carrier can be removed before completing the manufacture of the packages.

[0045] In one embodiment, the method comprises disposing a soft and sticky layer between the plurality of electronic components and the further carrier. Preferably, the soft and sticky layer is a high-temperature-resistant layer, for example, temperature-resistant up to at least 220°C. The soft and sticky layer can be adhesive on both sides and can be removable without leaving residues on the electronic components. The soft and sticky layer can be configured to withstand a diffusion soldering temperature without damage.

[0046] In one embodiment, the aforementioned support, which is a high-temperature-resistant support and which is covered with a high-temperature-resistant soft and sticky layer, may form part of the apparatus.

[0047] In one embodiment, the method comprises transferring the plurality of electronic components from the further carrier to one or more permanent carriers, in particular by means of batch diffusion soldering (i.e., connecting the electronic components to the at least one permanent carrier by means of simultaneous diffusion soldering) and / or by applying pressure and heat. For example, the permanent carriers may be various leadframe structures of a leadframe. Such a leadframe structure may comprise a die pad for receiving an electronic component (or a plurality of electronic components) and may comprise at least one conductor section comprising one or more conductors.However, other types of permanent supports may also be possible, for example, a DCB (Direct Copper Bonding) substrate, a DAB (Direct Aluminum Bonding) substrate, an AMB (Active Metal Brazing) substrate, an IMS (Insulated Metal Substrate), a PCB (Printed Circuit Board), etc. A solder layer comprising a solder material for performing diffusion soldering (or another type of soldering) may be preformed on the respective permanent support and / or on one or more pads of the respective electronic component.

[0048] In one embodiment, the solder material comprises tin or a tin alloy, in particular at least one from the group consisting of AgSn, AuSn, NiSn, CuSn, AgCuSn, and InSn. Tin can have excellent soldering properties. At least one additional metallic component can refine the properties of the solder material. The solder materials mentioned can be used for diffusion soldering.

[0049] In one embodiment, the solder material has a thickness in a range of 5 µm to 100 µm, particularly in a range of 10 µm to 50 µm. Thus, diffusion soldering can promote a compact design of the resulting package.

[0050] In one embodiment, the method comprises mounting the electronic component onto the adhesive base structure on an optically transparent temporary carrier and irradiating at least a portion of the base structure with electromagnetic radiation through the optically transparent temporary carrier to dissolve the base structure. Thus, it may be possible to connect the electronic component(s) by means of an adhesive base structure on a temporary carrier that is optically transparent to electromagnetic radiation suitable for dissolving the adhesive base structure. The electromagnetic radiation that triggers the dissolution of the adhesive base structure can then move through the temporary carrier to reach the adhesive base structure to be destroyed by the radiation.The described geometry can increase the reliability of the dissolution and detachment process, as it can be ensured that the entire connection area between the temporary carrier and the electronic component can be reached by the electromagnetic radiation beam.

[0051] In one embodiment, the method comprises irradiating the base structure by scanning the base structure using an electromagnetic radiation source. The scanning can be accomplished by moving, on the one hand, the electromagnetic radiation source and / or an electromagnetic radiation beam therefrom (for example, by tilting a reflection mirror) and, on the other hand, the base structure relative to each other. Thus, a relative movement can be adjusted between, on the one hand, the temporary carrier with the electronic component(s) and the adhesive base structure therebetween, and, on the other hand, the electromagnetic radiation source (for example, a laser device) or its beam (for example, a laser beam).This mutual movement can ensure that the electromagnetic radiation beam scans a predefined trajectory on the adhesive base structure, thereby dissolving the adhesive base structure material in a precisely definable manner. For example, a temporal sequence can be defined according to which the electronic components are forced to fall downwards due to gravity after dissolving a previously adhesive base structure material.

[0052] In one embodiment, the method comprises irradiating the base structure through a partially optically transparent and partially opaque mask arranged between the base structure and the electromagnetic radiation source. With such a configuration, the electromagnetic radiation is allowed to pass only through the optically transparent part(s) of the mask, but not through the opaque portion(s). This may enable the use of an electromagnetic radiation source that emits light over a wide spatial area. Irradiated portions may be defined by the mask design.

[0053] In particular, the mask may be embodied as a grayscale mask configured to irradiate a portion of the base structure corresponding to an edge of the electronic component with a higher intensity than another portion of the base structure corresponding to a center of the electronic component. In other words, the optically transparent portion of the mask may have a grayscale profile that allows different amounts of light to pass through different portions of the optically transparent portion. For example, a dark gray portion may allow less light to pass through than a light gray portion. Advantageously, an edge region of a transmissive window in the mask may be configured to allow more light transmission than a central region of the transmissive window.This can make the detachment process most efficient along the perimeter of the electronic component. It has been found that the detachment process can be carried out particularly reproducibly and precisely if the dissolution process of the adhesive base structure begins at the perimeter of the electronic component.

[0054] In one embodiment, the method comprises thinning and then separating a wafer into a plurality of electronic components while the wafer is arranged on the adhesive base structure. Thus, the adhesive base structure on a temporary carrier can hold the wafer and its individual electronic components in place during a singulation or dicing process. For example, the separation can be accomplished by mechanical dicing (e.g., using one or more cutting blades), laser dicing (e.g., using at least one laser beam), and / or dicing by etching (e.g., plasma dicing). An earlier wafer thinning process (e.g., accomplished by grinding) can also be performed while the wafer is attached to a temporary carrier by means of an adhesive base structure.After thinning and separating, the adhesive base structure can be released (particularly in a spatially resolved manner) to detach the thinned and separated electronic components.

[0055] In one embodiment, the method comprises forming pads on a thinned surface of the wafer after thinning and before dicing. Consequently, pads (e.g., electrically conductive connections) can still be formed on the thinned wafer at the wafer level. This can be accomplished using a metal deposition and patterning process.

[0056] In one embodiment, the device comprises the adhesive base structure configured to be released and thus removed when irradiated with electromagnetic radiation. For example, the adhesive base structure may be an adhesive that can be vaporized using a laser beam. Such a configuration may be preferred because the adhesive base structure disappears after the dissolution process and can therefore release the electronic component(s).

[0057] In another embodiment, the apparatus comprises the adhesive base structure configured to be transformed from an adhesive state to a non-adhesive or less adhesive state when irradiated with electromagnetic radiation. Thus, it is possible for the adhesive base structure to be made of a material that is chemically transformed into a less or non-adhesive configuration by the influence of light. For example, detachment can then be achieved by transforming the adhesive base structure into a configuration in which its adhesive force is below its gravity, so that the electronic component simply falls downward without requiring further action.

[0058] In one embodiment, the electromagnetic radiation source comprises a laser. This has the advantage that the wavelength and spatial range of influence can be precisely selected to ensure the detachment of the electronic component in a very precise and definable manner. The high power of a laser beam can also be extremely advantageous for this purpose.

[0059] In one embodiment, the alignment unit is configured to statically place the vertically falling electronic component in lateral alignment with the statically placed carrier, such that the vertically falling electronic component lands on the carrier (which is static during the fall). Such a configuration is described in Fig. 1. The detached electronic component simply moves downward under gravity and reaches the wearer without requiring any further action.

[0060] In another embodiment, the alignment unit is configured to dynamically move the electronic component and the carrier relative to each other along a lateral direction that is transverse to gravity, so that the downwardly falling electronic component lands on the carrier, taking into account the lateral movement (in particular during the fall). Such a configuration is described in Fig. 2. In such an embodiment, it is possible, for example, for the electronic component to move horizontally and the carrier to remain stationary, or vice versa, so that the detached electronic component can have motion trajectories in both the horizontal and vertical directions and / or such that the carrier can move horizontally. The relative carrier-component positioning can be adjusted taking into account the motion components of the electronic component and / or the carrier.

[0061] In one embodiment, the apparatus comprises a control unit configured to control the electromagnetic radiation source to perform the irradiation and the alignment unit to perform the alignment. For example, such a control unit may be a processor that coordinates the functionality of said components of the system. For example, such a control unit may be controlled by means of a software program.

[0062] In one embodiment, the apparatus comprises the carrier having an adhesive medium on a major surface at which the falling electronic component is stopped. The fallen electronic component may preferably adhere to the adhesive medium. For example, the adhesive medium may comprise at least one of an adhesive solder paste, an adhesive sintering paste, and an adhesive. When the detached electronic component falls as a result of the loss of adhesive force by the dissolved adhesive base structure and reaches the carrier, the adhesive medium thereon causes the downwardly falling electronic component to stop and remain adhered to the adhesive medium.When the adhesive medium is configured as an adhesive solder paste, adhesive sinter paste, or the like, the resulting configuration is directly ready for a permanent connection between the carrier and the electronic component, for example, by soldering or sintering. Thus, exemplary embodiments can significantly increase the efficiency of a die assembly process.

[0063] The adhesive medium can also be referred to as a tacky mediator. The adhesive medium can be a tacky paste, which can be directly subjected to soldering or sintering. It is also possible for the adhesive medium to be a tacky paste applied to a (for example, sputtered) layer of diffusion solder on the substrate. Such a tacky paste can be volatile when the precipitated electronic component is bonded to the substrate using diffusion soldering, which can involve temperatures above 200 °C.

[0064] In one embodiment, the apparatus comprises the electronic component having pads on both opposing major surfaces and / or experiencing vertical current flow during operation. For example, the electronic component may be a field-effect transistor chip having a drain pad on one major surface and both a source pad and a gate pad on the other major surface. Such a device may have vertical current flow when active.

[0065] In one embodiment, a thickness of the electronic component may be in a range of 5 µm to 100 µm, in particular in a range of 10 µm to 60 µm. Such very thin electronic components, in particular semiconductor chips, may be particularly susceptible to damage during conventional needle-assisted detachment processes, in particular due to the phenomenon of die knocking. However, a laser-assisted detachment process according to an exemplary embodiment may eliminate the phenomenon of die knocking.

[0066] In one embodiment, the electronic component is configured as a power semiconductor chip. Thus, the electronic component (e.g., a semiconductor chip) can be used for power applications, for example, in the automotive sector, and can, for example, have at least one integrated insulated-gate bipolar transistor (IGBT) and / or at least one transistor of another type (e.g., a MOSFET, a JFET, a HEMT, etc.) and / or at least one integrated diode. Such integrated circuit elements can, for example, be manufactured using silicon technology or based on wide-bandgap semiconductors (e.g., silicon carbide, gallium nitride). A semiconductor power chip can include one or more field-effect transistors, diodes, inverter circuits, half-bridges, full-bridges, drivers, logic circuits, other devices, etc.

[0067] In one embodiment, the package is configured as a power package. A power package may be a package that includes at least one power chip as the electronic component. Thus, the package may be configured as a power module, for example, an encapsulated power module, for example, a semiconductor power package. For example, an exemplary embodiment of the package may be an intelligent power module (IPM). Another exemplary embodiment of the package is a dual inline package (DIP).

[0068] In one embodiment, the package comprises an encapsulation that encapsulates at least a portion of the electronic component. In the context of the present application, the term “encapsulation” may in particular refer to a substantially electrically insulating material that surrounds at least a portion of an electronic component and a portion of a carrier to provide mechanical protection, electrical insulation, and optionally contribute to heat dissipation during operation. In particular, the encapsulation may be a molding compound. A molding compound may comprise a matrix of flowable and curable material and filler particles embedded therein. For example, the filler particles may be used to adjust the properties of the molding compound, in particular to enhance thermal conductivity.As an alternative to a molding compound (e.g. based on epoxy resin), the encapsulation can also be a potting compound (e.g. based on a silicone gel).

[0069] In one embodiment, the package comprises at least one electrically conductive coupling element that electrically couples the electronic component to the carrier (in particular to a die pad and / or to at least one conductor). Such an electrically conductive coupling element can be a clip, a bonding wire, or a bonding tape. A clip can be a curved electrically conductive body that establishes an electrical connection with a high connection area to an upper main surface of a corresponding electronic component. In addition or alternatively to such a clip, it is also possible to implement one or more other electrically conductive connecting bodies in the package, for example a bonding wire and / or a bonding tape that connects the electronic component to the die pad and / or a conductor, or connects different pads of an electronic component.

[0070] For example, according to other example embodiments, a package may be configured as one of the group consisting of a leadframe-connected power module, a control integrated power system (CIPOS) package, a transistor outline (TO) package, a quad flat no leads (QFN) package, a small outline (SO) package, a small outline transistor (SOT) package, and a thin small outline (TSOP) package. Packages for sensors and / or mechatronic devices are also possible embodiments. Furthermore, example embodiments may also relate to packages that function as nanobatteries or nanofuel cells or other devices with chemical, mechanical, optical, and / or magnetic actuators.Therefore, according to an exemplary embodiment, the package is fully compatible with standard packaging concepts and appears externally as a conventional package, which is extremely user-friendly.

[0071] In one embodiment, at least one further electronic component is mounted on the carrier. Thus, a plurality of electronic components, each of which can be detached from an adhesive base structure, can be mounted side by side on the same carrier. For example, at least two electronic components can be mounted on one carrier. This can make it possible to realize even complex or sophisticated electronic functionality.

[0072] A semiconductor substrate, in particular a silicon substrate, can be used as the substrate or wafer that forms the basis of the electronic components. Alternatively, a silicon oxide or other insulating substrate can be provided. It is also possible to implement a germanium substrate or a III-V semiconductor material. For example, exemplary embodiments can be implemented using GaN or SiC technology.

[0073] The above and other objects, features and advantages of the present invention will become apparent from the following description and the appended claims, taken in conjunction with the accompanying drawings, in which like parts or elements are designated by like reference numerals. Short description of the drawings

[0074] The accompanying drawings, which are included to provide a further understanding of exemplary embodiments of the invention and constitute a part of the specification, illustrate exemplary embodiments of the invention.

[0075] In the drawings: Fig. 1 shows an apparatus according to an exemplary embodiment. Fig. 2 shows an apparatus according to an exemplary embodiment. Fig. 3 shows an apparatus according to an exemplary embodiment. Fig. 4 to Fig. 6 show various views of structures obtained during the execution of a method according to an exemplary embodiment. Fig. 7 to Fig. 9 show various views of structures obtained during the execution of a method according to an exemplary embodiment. Fig. 10 shows an apparatus according to an exemplary embodiment. Fig. 11 shows an apparatus according to an exemplary embodiment. Fig. 12 and Fig. 13 show various views of structures obtained during the execution of a method according to an exemplary embodiment. Fig. 14 and Fig. 15 show various views of structures obtained during the execution of a method according to an exemplary embodiment. Fig. 16 to Fig. 21 show various views of structures obtained during the execution of a method according to an exemplary embodiment. Detailed description of exemplary embodiments

[0076] The representation in the drawing is schematic and not to scale.

[0077] Before exemplary embodiments are described in more detail with reference to the figures, some general considerations are summarized based on which exemplary embodiments were developed.

[0078] Traditionally, pick-and-place processes are used to peel known good dies from a dicing tape by pushing a needle from the back into a central portion. As a result, the tape begins to peel away from the corners of the die. However, this can cause adjacent dies to butt against each other. This phenomenon, known as die knocking, can cause severe damage to the die. For example, a small radius can cause pitting and / or cracking.

[0079] Furthermore, delamination of the dies from the tape using the conventional approach described can take a significant amount of time.

[0080] Furthermore, the risk of die knocking may require the creation of a large safety margin around an active area. This, in turn, can lead to a reduced active area. Thus, due to the die knocking effect, no improvement in the utilization of the significant area is conventionally possible. Die knocking during die pick-up due to needle ejection phenomena may require defined distances from neighboring dies to avoid damage. A minimum distance between active areas of the dies can be 90 µm—including the aforementioned safety margin. Typical values ​​for a distance between the active areas can even exceed 100 µm.

[0081] The problems associated with die knocking can be even more severe for small-kerf technologies, such as plasma dicing. Plasma dicing can reduce damage to the bulk material compared to mechanical sawing. Furthermore, plasma dicing can produce a very narrow kerf width (typically less than 10 µm), making the aforementioned safety margins insufficient in such a scenario.

[0082] In conclusion, needle-based die detachment can cause damage and may require countermeasures that affect units per hour and chip design and manufacturing effort.

[0083] According to an exemplary embodiment of a first aspect, an electronic component is attached to a temporary carrier via an adhesive base structure. The attached electronic component can be separated from the temporary carrier by dissolving a sacrificial material of the base structure. By dissolving, the previously adhesive base structure can be locally removed (e.g., evaporated). For example, this removal, dissolution, or detachment can be triggered by electromagnetic radiation, heat, or chemically. Upon detachment of the electronic component from the previously adhesive base structure, the detached electronic component can fall by gravity without the need for further action and can land on a spatially aligned carrier below. Thus, the detachment process can already suitably prepare for the assembly of the falling electronic component on the carrier below.By removing the adhesive base structure, the adhesive force can disappear, causing the electronic component to fall downward. This can enable efficient handling of the electronic components.

[0084] According to an exemplary embodiment of a second aspect, an adhesive base structure with the attached electronic component is selectively irradiated with electromagnetic radiation to trigger the detachment of the electronic component from the adhesive base structure. This can enable a pick-and-place unit to pick up the detached electronic component on one side and further pick up the picked electronic component on an opposite side to place the electronic component on a carrier. After the further picking process, the initially used picking tool can be removed from the electronic component.Selectively irradiating an adhesive base structure with electromagnetic radiation can cause a loss of adhesive holding force, allowing a pick-and-place unit, which has at least two pick-up tools for handling the electronic components on either side, to place them with a desired main surface onto a target surface, such as a permanent carrier. This architecture can enable the electronic component to be mounted on the carrier in a very simple and reliable manner and the electronic components to be handled efficiently.

[0085] According to an exemplary embodiment of a third aspect, a preform of an electronic component is attached to a temporary carrier on one side. Furthermore, the electronic component may be attached to another temporary carrier on an opposite side. Thereafter, the initial temporary carrier may be removed from the electronic component. By irradiating an adhesive base structure between the further temporary carrier and the electronic component with electromagnetic radiation, the electronic component may be detached from the adhesive base structure. This may allow the electronic component to then be picked up and placed on a target surface, for example, a permanent carrier.Such an approach can enable the electronic component to be mounted on the carrier in a very simple and reliable manner and the electronic components to be handled efficiently.

[0086] According to various embodiments, a pick-and-place architecture with laser-assisted die detachment may enable a reduced chip edge safety zone. Advantageously, die picking may be performed without a pin ejection, but, for example, in a laser-assisted manner. A correspondingly manufactured electronic component (e.g., a semiconductor chip) may be formed with an extremely small edge safety zone. For example, such a safety edge zone of an electronic component according to an exemplary embodiment may be smaller than 90 µm, in particular in a range from 70 µm to below 90 µm, for example, below 80 µm. For example, a safety edge zone may extend as a circumferentially closed edge structure that extends around an entire circumference of an active area of ​​the electronic component.Preferably, such an electronic component can be singulated from a wafer assembly using plasma dicing, chemical etching, or laser dicing at its edge. After singulation, such an electronic component can be transferred using a laser-assisted pick-and-place process, in which die knocking is inherently prevented. Consequently, a gentle method for performing die picking for thin and fragile dies can be provided. Furthermore, a reduced unused edge area can be enabled.

[0087] Fig. 1 shows an apparatus 120 according to an exemplary embodiment. Fig. 1 a direct dynamic detachment process.

[0088] The apparatus 120 shown includes an electromagnetic radiation source 106 embodied as a laser source. The electromagnetic radiation source 106 is configured to irradiate a mounting portion 150 of an adhesive base structure 102 with electromagnetic radiation 104. For example, the emitted beam of electromagnetic radiation 104 may be ultraviolet (UV) light configured to dissolve the material of the adhesive base structure 102, as described in more detail below. For example, the UV light may be a pulsed laser light having a wavelength of 265 nm. It is also possible for the UV light generated by the electromagnetic radiation source 106 to have a wavelength of 355 nm. More generally, the electromagnetic radiation source 106 may be a laser source configured to emit a pulsed or continuous laser beam.The generated beam of electromagnetic radiation 104 can be directed onto a reflection mirror 152, from where the electromagnetic radiation 104 is reflected toward an optically transparent temporary support 112. The optically transparent temporary support 112 can have a diameter in a range of approximately 20 cm to 50 cm (8 inches to 20 inches), for example, can have a diameter of approximately 30 cm (12 inches). The optically transparent temporary support 112 can be a glass plate. The beam of electromagnetic radiation 104 propagates through the optically transparent temporary support 112. A plurality of electronic components 100 are mounted on the back of the optically transparent temporary support 112, i.e., on the main surface of the optically transparent temporary support 112 facing away from the incident beam of electromagnetic radiation 104.More specifically, the electronic components 100 are mounted on the optically transparent temporary carrier 112 by means of an adhesive base structure 102 therebetween.

[0089] The electronic components 100 may be semiconductor chips that have been diced from a previously integral wafer. For example, the electronic components 100 may be power semiconductor chips. For example, each of the electronic components 100 may comprise at least one monolithically integrated circuit element, for example, a field-effect transistor (for example, a metal-oxide-semiconductor field-effect transistor, MOSFET, a junction field-effect transistor, JFET), a diode, etc. A vertical thickness, d, of the electronic components 100 may be less than 100 µm, for example, in a range from 20 µm to 80 µm, for example, 50 µm. An area of ​​a main surface of the electronic components 100 may be in a range of 1 mm 2 up to 35 mm2 be.

[0090] In the illustrated embodiment, the adhesive base structure 102 is a continuous layer of a solid or viscous adhesive by which the electronic components 100 are held on a lower major surface of the optically transparent temporary carrier 112. In the illustrated embodiment, the adhesive base structure 102 is a continuous layer covering the major surfaces of all electronic components 100 and sections therebetween. Alternatively, the adhesive base structure 102 may be formed from a plurality of unconnected islands, each for holding a respective electronic component 100 on the optically transparent temporary carrier 112 by means of an adhesive force.

[0091] The above-mentioned electromagnetic radiation source 106 in combination with the reflection mirror 152, an alignment camera 154 (configured for alignment and inspection), and a control unit 124 constitute a scanner for scanning the component-holding main surface of the optically transparent temporary carrier 112. The scanner can scan the temporary carrier 112 along a predefined or definable trajectory. Such a trajectory can be, for example, a meander trajectory, a spiral trajectory, etc. In other words, the scanner can selectively irradiate a specific surface portion of the temporary carrier 112, including the adhesive base structure 102 thereon, with electromagnetic radiation 104.Thus, it may be possible to irradiate the base structure 102 by scanning the base structure 102 with a beam of electromagnetic radiation 104 emitted by the electromagnetic radiation source 106. This may be accomplished by moving, on the one hand, the electromagnetic radiation source 106 and / or the beam of electromagnetic radiation 104 and, on the other hand, the base structure 102 relative to each other. For example, the reflection mirror 152 may be tilted to move the beam of electromagnetic radiation 104 impinging on the adhesive base structure 102. This may result in a relative movement between the beam and the base structure 102, and consequently in scanning.

[0092] Advantageously, the combination of the properties of the adhesive base structure 102 and the laser light can ensure that the adhesive base structure 102 is released and dissolves when irradiated with laser light of sufficient intensity and a suitable wavelength. In this context, release can mean dissolving, removing, or evaporating the adhesive base structure 102 or a portion thereof, which therefore disappears in the sections irradiated with the laser light. The adhesive base structure 102 can be made of a UV-sensitive adhesive. For example, irradiating such an adhesive base structure 102 with UV light can convert the material of the adhesive base structure 102 into carbon dioxide, water vapor, nitrogen gases, etc.In the embodiment shown, the scanner scans a mounting portion 150 of the adhesive base structure 102 with the electromagnetic radiation 104, thereby selectively removing the adhesive base structure 102 in the mounting portion 150. By selectively irradiating the mounting portion 150, the electronic component 100, which was previously held thereon by adhesion, is detached from the mounting portion 150 and therefore falls downwards due to gravity, see reference numeral 156.

[0093] As also in Fig. 1, a plurality of permanent supports 108, each for supporting a respective electronic component 100 to form a respective package 158, are arranged beneath the electronic components 100 mounted on the temporary support 112. For example, the supports 108 may be embodied as a leadframe structure forming part of a common leadframe. Such supports 108 may be metal plate sections, for example, made of copper. For example, a copper leadframe may be used to form the supports 108 and may have a size of up to 100 x 300 mm 2 As an alternative to leadframe-like supports 108, other embodiments may also use laminate-like permanent supports 108, etc.

[0094] Referring again to the apparatus 120, it comprises an alignment unit 122 for aligning a mutual position between, on the one hand, a respective permanent carrier 108 for supporting a respective electronic component 100 and, on the other hand, the detached electronic component 100 falling downwards under gravity, so that the downwardly falling electronic component 100 lands on the associated carrier 108. The alignment unit 122 can be used for the purpose of aligning index holes 160 and / or upset structures 162 of the lead frame. As shown, the alignment unit 122 can be controlled by means of a control unit 124 and can ensure a correct mutual spatial relationship between a laser-detached, downwardly falling electronic component 110 and the associated carrier 180.The illustrated control unit 124, for example, a processor or a control computer, may be configured to control the electromagnetic radiation source 106 to perform the irradiation, and the alignment unit 122 to perform the alignment. For example, the alignment unit 122 may force the temporary carrier 112 and / or the array of carriers 108 to move forward (for example, toward the right side of . Fig. 1) after the electromagnetic radiation source 106 has detached a respective electronic component 100 from the temporary carrier 112 and the fallen electronic component 100 has landed on an associated carrier 108. This procedure can then be repeated with the next electronic component 100 and the carrier 108.

[0095] According to Fig. 1, the alignment unit 122 is configured to statically place the vertically dropping electronic component 100 in lateral alignment with the statically placed carrier 108, such that the vertically dropping electronic component 100 lands on the static carrier 108. Thus, the alignment unit 122 can adjust a mutual alignment between the carrier 108 and the electronic component 100 with respect to a vertical optical axis 164 by horizontally moving the carrier 108 and / or the electronic component 100 only before a detachment process. During the detachment process, the carrier 108 and the electronic component 100 can remain at static positions in the horizontal direction.After the detachment process, the carriers 108 and / or the electronic components 100 may be moved horizontally with respect to the beam of electromagnetic radiation 104 to align a next pair of carrier 108 and electronic component 100.

[0096] As an alternative to sequentially detaching the individual electronic components 100 from the base structure 102, it may also be possible to adapt the electromagnetic radiation-based detachment such that a group of electronic components 100 is simultaneously detached from the adhesive base structure 102 by being irradiated together by the electromagnetic radiation 104.

[0097] Referring now in more detail to the process of forming a package 158, Fig. 1, each carrier 108 has an adhesive medium 126 on a top major surface against which the landing electronic component 100 is stopped. The adhesive medium 126 may, for example, comprise an adhesive solder paste. When a detached electronic component 100 lands on an associated carrier 108, it is forced by the sticky adhesive medium 126 to remain on the carrier 108. Thereafter, the carrier-component-adhesive medium assembly may be subjected to soldering to form a permanent solder connection between the carrier 108 and the electronic component 100 using the adhesive medium 126 made of a solderable material. For example, the adhesive medium 126 may be a sticky paste, which may have a thickness of, for example, 80 µm to 120 µm.

[0098] Thereafter, one or more electrical connections of the electronic component 100 can be established, for example, using electrically conductive connection structures, for example, at least one bond wire and / or clip (not shown). The electronic component 100 and the carrier 108, as well as the medium 126 and the optional electrically conductive connection structure, can then be subjected to encapsulation, for example, molding. The individual packages 158 can then be separated from the leadframe assembly.

[0099] By taking the described measures, very simple handling of the electronic components 100 can be enabled without the risk of damage. In short, a direct transfer of electronic components 100 to a carrier 108 can be achieved. In particular, no pick-and-place configuration using a needle to lift the electronic components 100 from a backside is required. Consequently, the problems associated with die knocking can be overcome. In contrast, chip detachment can be accomplished in a laser-assisted manner by selectively detaching portions of an adhesive base structure 102 to thereby detach the individual electronic components 100 using gravity.

[0100] As already mentioned, the adhesive base structure 102 can be configured to release when irradiated with UV electromagnetic radiation 104. Electromagnetic radiation 104 of a different wavelength can be used, for example, visible light and / or infrared light. It is also possible to implement another trigger for releasing the adhesive base structure 102, for example, heat or a chemical treatment. In the described preferred embodiment, however, the adhesive base structure 102 is configured to be converted from an adhesive solid or viscous state to a gaseous state, such that it disappears from the interface between the temporary carrier 112 and the electronic component 100 when irradiated with the electromagnetic radiation 104. Consequently, the adhesive base structure 112 can Fig. 1 between the temporary carrier 112 and the electronic component 100 can be completely removed, rather than being converted from an adhesive configuration to a less adhesive configuration. This can make the detachment process fast, accurate, and highly reproducible.

[0101] In order to process electronic components 100 of different types with the same apparatus 120, it may be possible to set an adaptive exposure pattern. A vertical distance, h, between the adhered electronic component 100 and the top surface of the adhesive medium 126 can be set appropriately and depending on the application. The coordinate systems x1, y1 of the permanent supports 108 and the coordinate systems x2, y2 of the temporary support 112 can be set using the alignment unit 122. A movement dimension ΔX1 of the permanent support 108 and a movement dimension ΔX2 of the temporary support 112 after each localized dissolution process can also be set using the alignment unit 122.

[0102] Fig. 2 shows an apparatus 120 according to an exemplary embodiment. Illustratively, the embodiment of Fig. 2 a direct dynamic detachment process with an on-the-fly transfer.

[0103] The apparatus 120 according to Fig. 2 differs from the apparatus 120 according to Fig. 1 in particular that according to Fig. 2, the alignment unit 122 is configured to dynamically move the electronic components 100 and the carrier 108 relative to each other along a lateral direction (which is a horizontal direction here) transversely (which is perpendicular here) to the force of gravity (which is effectively along a vertical direction). This is accomplished in such a way that the downwardly falling electronic component 100 lands on the carrier 108 taking into account the lateral movement, i.e., has a vertical and a horizontal movement component during the fall. Consequently, the optically transparent temporary carrier 112 can also be horizontally moved towards the right side of Fig. 2. As a result, a falling electronic component 100, which is detached from the temporary carrier 112 by means of UV radiation, can thus move along an inclined trajectory instead of purely vertically, as indicated by the reference numeral 126 in Fig. 2. The alignment unit 122 can take into account horizontal and vertical motion components of a falling electronic component 100 for correctly positioning the associated carrier 108 with respect to the electronic component 100.

[0104] Fig. 3 shows an apparatus 120 according to another exemplary embodiment. While Fig. 1 and Fig. 2 shows embodiments in which a spatially limited laser beam dynamically scans an adhesive base structure 102 to release or dissolve it in order to detach the electronic components 100, Fig. 3 an embodiment in which a mask 114 is used in combination with a spatially broad illumination by means of UV light.

[0105] According to Fig. 3, the adhesive base structure 102 is irradiated with UV light through a partially optically transparent and partially opaque mask 114, which is arranged between the light-sensitive adhesive base structure 102 and the light-emitting electromagnetic radiation source 106 (the latter is in Fig. 3 and emits the incident electromagnetic radiation 104). According to Fig. 3, the mask 114 is advantageously embodied as a grayscale mask configured to irradiate a portion of the base structure 102 that is connected to an edge of the electronic component 100 with a higher intensity than another portion of the base structure 102 that is connected to a center of the electronic component 100. To keep it brief, Fig. 3 an alternative exposure concept based on grayscale lithography.

[0106] More precisely, Fig. 3 shows a diagram having an abscissa 166, along which a spatial coordinate is plotted, corresponding to the horizontal extent of the adhesive base structure 102. An irradiation intensity is plotted along an ordinate 168, showing an electromagnetic radiation intensity according to which the respective spatial section of the adhesive base structure 102 is irradiated with UV light due to the spatially dependent optical transmittance characteristic of the transmissive section 173 of the mask 114, which is delimited by the opaque sections 174. As can be seen from the plotted diagram, the optical transmittance of the transmissive section 173 has a maximum at the edges 172 and a minimum in a central section 176 of the adhesive base structure 102.As a result, the process of UV-triggered detachment or dissolution of the adhesive base structure 102 begins at the peripheral edge of the adhesive base structure 102, as shown by arrows 178. This can lead to a highly controlled decomposition of the adhesive base structure 102, starting at its edges and extending from there toward the center. This, in turn, can enable outgassing from the outer perimeter of the die-like electronic component 100. Advantageously, the electronic component 100 is fabricated according to . Fig. 3 is detached from the optically transparent temporary carrier 112 in a well-controllable manner.

[0107] Fig. 4 to Fig. 6 show various views of structures obtained during the execution of a method according to an exemplary embodiment.

[0108] Referring to Fig. 4, a semiconductor wafer 116 is thinned by grinding using a grinding tool 180, while the wafer 116 is arranged on an adhesive base structure 102. The latter, in turn, is formed on an optically transparent temporary carrier 112. The adhesive base structure 102 may be made of a photopolymer. The optically transparent temporary carrier 112 may, for example, be a UV-transparent carrier, for example made of glass, such as Borofloat®. For example, the wafer 116 may be a processed semiconductor wafer, for example a silicon wafer. As shown, the pads 117, 118 are already formed on a lower major surface of the wafer 116, which faces away from the grinding tool 180. For example, each pair of pads 117, 118 may be a source pad and a gate pad of a transistor chip, which may later be singulated from the wafer 116 as respective electronic components 100.

[0109] Referring to Fig. 5, the wafer 116 has been separated into a plurality of electronic components 100 while the wafer 116 is still arranged on the adhesive base structure 102. Such separation can be accomplished, for example, by mechanical dicing, laser dicing, and / or plasma dicing.

[0110] After the thinning, which in Fig. 4, and before the separation described above with reference to Fig. As described in Figure 5, the pads 119 can be formed on the thinned surface of the wafer 116, for example, one for each electronic component 100. For example, each pad 119 can be a drain pad of the aforementioned transistor chip. Thus, the fabricated electronic components 100 can have a vertical current flow through the semiconductor body 113 and between the pads 117, 118, 119. In other words, the electronic component 100 is equipped with pads 117, 118, 119 on both opposite main surfaces and experiences a vertical current flow during operation.

[0111] To keep it short, Fig. 5, that the wafer 116 can be subjected to backside metallization and dicing (for example, using a low-kerf technology, for example, plasma dicing).

[0112] Referring to Fig. 6 was the structure which in Fig. 5 is sent to a backend processing. The structure, which is shown in Fig. 5, has been rotated from top to bottom and is now subjected to irradiation with electromagnetic radiation 104 emitted by the electromagnetic radiation source 106. More precisely, only the electronic component 100 on the right side of Fig. 6 is irradiated with UV light so that the associated portion of the adhesive base structure 102 is dissolved. This causes only this electronic component 100 to fall downwards due to a loss of adhesion, see reference numeral 156. Although this is Fig. 6, the electronic component 100 may fall directly onto an aligned carrier 108, for example a lead frame structure as described above with reference to Fig. 1 and Fig. 2 is described.

[0113] Fig. 7 to Fig. 9 show various views of structures obtained during the execution of a method according to exemplary embodiments. To keep it brief, in particular Fig. 9 shows a pick-and-place configuration using flip tools in combination with laser-assisted detachment of an electronic component 100. A flip bonder can be used for this purpose.

[0114] Referring to Fig. 7, a wafer 116 is subjected to thinning by grinding, as described with reference to Fig. 4. This can lead to the formation of bulges 182. Particularly when processing thin wafers 116, bulges 182 can be created during grinding as non-underfilled areas. A water-soluble resin can be used to prevent this, for example, HogoMax™. According to Fig. 7, the temporary carrier 112 may be a UV-transparent carrier, for example, a silicon dioxide plate or a tape. The adhesive base structure 102 may be a UV adhesive (e.g., having a thickness in a range of 0.5 µm to 15 µm).

[0115] A difference between Fig. 7 and Fig. 4 is that according to Fig. 4 the pads 117, 118 are embedded in the adhesive base structure 102, whereas according to Fig. 7 are arranged on top of the adhesive base structure 102.

[0116] Referring to Fig. 8 is the structure of Fig. 7 after grinding, backside metallization and separation. These processes can be described as with reference to Fig. 4 and Fig. 5 described.

[0117] For example, if the silicon thickness of the respective electronic component 100 is approximately 40 µm, the singulation can be accomplished using a plasma treatment with patterned copper on the backside. This can be particularly suitable for a hard carrier. In another scenario, where the semiconductor thickness is no greater than 110 µm, the singulation can be performed using laser dicing, which is also compatible with a hard carrier. If the thickness of the semiconductor body is greater than 110 µm, the singulation can be performed using mechanical dicing on a tape.

[0118] Referring to Fig. 9, further handling of the electronic components 100 can be carried out while the electronic components 100 remain attached to the adhesive base structure 102 on the upper main surface of the optically transparent temporary carrier 112. The electronic components 100 according to Fig. 9 do not fall down under gravity when the adhesive base structure 102 is released, since the electronic components 100 are in accordance with Fig. 9 are mounted on the top side instead of on the bottom side of the temporary support 112.

[0119] The procedure of handling the electronic components 100 is carried out by means of the apparatus 120, which in Fig. 9. The apparatus 120 includes the electromagnetic radiation source 106, for example, a laser source, configured to irradiate a mounting portion 150 of the adhesive base structure 102, on which an electronic component 100 to be detached is mounted. By irradiating the mounting portion 150 of the base structure 102 with a beam of electromagnetic radiation 104, the mounting portion 150 is destroyed and removed, thereby detaching the electronic component 100 from the mounting portion 150, since no adhesive force is exerted.

[0120] Furthermore, the apparatus 120 according to Fig. 9, a pick-and-place unit 128 is configured to pick up the electronic component 100 on one side after detachment by means of a pick-up tool 110. In the embodiment shown, the pick-up tool 110 is a vacuum suction tool that lifts the detached electronic component 100 therebetween by means of a vacuum force. In the embodiment shown, the main surface of the electronic component 100, at which it is picked up by the pick-up tool 110, corresponds to the backside metallization in the form of the pad 119. However, for certain applications, it may be desirable for the pad 119 (e.g., a drain pad of a transistor chip) to be placed on a target surface, for example, a carrier 108 (in Fig. 9 not shown).

[0121] To achieve this goal, the pick-and-place unit 128 includes a further pick-up tool 110'. In this described embodiment, the further pick-up tool 110' is a further vacuum suction tool configured to hold the detached electronic component 100 therebetween by means of a vacuum force. Fig. For simplicity, only one pick-up tool 110 / 110' is shown in Figure 9, however, in this embodiment, two separate pick-up tools 110, 110' are provided. To make the pad 119 accessible for placement on the aforementioned target surface, the electronic component 100 can be picked up by the further pick-up tool 110' at its main surface, which has the pads 117, 118, while still being held by the pick-up tool 110 at the main surface, which has the pad 119. After the electronic component has been picked up by the further pick-up tool 110' at its opposite side, the pick-up tool 110 can be removed from the electronic component 100. Subsequently, the exposed pad 119 of the electronic component 100 can be placed by the further pick-up tool 110' on the target surface, for example, on a permanent carrier 108.

[0122] In summary, the electronic component 100 can be formed or placed on the adhesive base structure 102 on the optically transparent temporary carrier 112. The base structure 102 can then be irradiated with the electromagnetic radiation 104 through the optically transparent temporary carrier 112 to release the base structure 102 beneath the electronic component 100. Consequently, a portion of the base structure 102 can be released while the electronic component 100 is disposed on a top side of the adhesive base structure 102. After release, the electronic component 100 is picked up on one side thereof by the pick-up tool 110. After this pick-up, the electronic component 100 is further picked up on an opposite, other side thereof by the further pick-up tool 110'.Illustratively, a detached, separated, and picked-up electronic component 100 is transferred from the pick-up tool 110 to the further pick-up tool 110'. In the embodiment shown, the pick-up tool 110 is a vacuum suction tool that lifts the detached electronic component 100 therebetween using a vacuum force. Subsequently, the electronic component 100 is placed with one side on the carrier 108 by the further pick-up tool 110'. In the embodiment shown, the further pick-up tool 110' is another vacuum suction tool that holds the electronic component 100 therebetween using a vacuum force.

[0123] The embodiment of Fig. 9 has the advantages of a small number of process steps, rapid detachment from the temporary carrier 112, significantly fewer problems compared to the use of needles, minimal impact due to laser detachment (thus enabling thinner silicon chips), no die knocking occurs, carrier reuse is easy (in particular, without etching or thinning), and a long lifetime of the temporary carrier 112 can be achieved. Furthermore, a particularly gentle way of performing die picking for thin and fragile dies can be provided. With regard to the reduced edge problems, a lower manufacturing effort can be achieved. In particular, laser-assisted die detachment has proven extremely advantageous.

[0124] Fig. 10 shows an apparatus 120 according to another exemplary embodiment. In this embodiment, the electronic components 100 are mounted on an adhesive base structure 102, which is applied to an underside of an optically transparent temporary carrier 112. Thereafter, a portion of the base structure 102, which relates to a specific electronic component 100, is detached by irradiating the portion of the base structure 102 with electromagnetic radiation 104 emitted by an electromagnetic radiation source 106, thereby detaching the electronic component 100. As a result, the detached electronic component 100 falls downwards by gravity, see reference numeral 156, onto a permanent carrier 108 (in Fig. 10 not shown). This process can be described, for example, as above with reference to Fig. 1, Fig. 3 or Fig. 6 described.

[0125] To keep it short, the embodiment of Fig. 10, a direct transfer of an electronic component 100 by means of laser-assisted detachment. This can lead to the detached electronic component 100 automatically falling onto a leadframe-like carrier 108.

[0126] Fig. 11 shows an apparatus 120 according to yet another exemplary embodiment. The embodiment of Fig. 11 involves the mounting and re-mounting of electronic components 100 on two temporary supports 112, 112' (only one of which is in Fig. 11). A simple pick-and-place tool and laser-assisted chip removal can also be implemented.

[0127] The embodiment of Fig. 11 can be based on a structure as described in Fig. 9, but without the two-part receiving tool 110 / 110' shown there. Based on such a structure, the upper main surface of the electronic components 100 can be Fig. 9 to a further temporary carrier 112', for example, a tape or a hard carrier. More specifically, the pads 119 of the electronic components 100 can be connected to an adhesive base structure 102 on the further temporary carrier 112'. Thereafter, the initial temporary carrier 112 can be separated, for example, by irradiation with electromagnetic radiation or by applying heat. The resulting structure can be turned from top to bottom, which can lead to the structure shown in Fig. 11 (without the receiving tool 110). As shown in Fig. As shown in Figure 11, a portion of the adhesive base structure 102 on the further temporary carrier 112' may then be selectively irradiated with the electromagnetic radiation 104 emitted by the electromagnetic radiation source 106 to detach it from the further temporary carrier 112'. Thereafter, the detached electronic component 110 may be picked up by the pick-up tool 110 of a pick-and-place assembly 128 at the exposed main surface having the pads 117, 118, and may be placed with the exposed pad 119 on a target surface (e.g., a permanent carrier 108).

[0128] Consequently, the electronic components are already placed on the temporary carrier 112' with their pads 119 before being picked up. After picking up, the electronic component 100 is placed on the carrier 108 with the side with the pad 119. After the electronic components 100 have been mounted on the adhesive base structure 102 on the optically transparent additional temporary carrier 112', at least a portion of the base structure 102 is irradiated with the electromagnetic radiation 104 through the optically transparent additional temporary carrier 112' in order to detach the base structure 102 and thereby detach the associated electronic component 100.

[0129] To carry out the described method, the apparatus 120 can be used, which in Fig. 11. The apparatus 120 comprises a fastening unit 130 (schematically shown in Fig. 11) which is configured to attach a preform of the electronic component 100 at one side to a temporary carrier 112 during the manufacture of the electronic component 100, see Fig. 9 (without the receiving tool 110 / 110'). Another fastening unit 132 (schematically shown in Fig. 11) is configured to attach the electronic components 100 to the further temporary carrier 112' on an opposite other side. The electromagnetic radiation source 106 also forms part of the apparatus 120 and is configured to irradiate a portion of the adhesive base structure 102 disposed between the temporary carrier 112' and the electronic components 100, thereby detaching the electronic component 100 from the adhesive base structure 102. The pick-and-place unit 128 of the apparatus 120 is configured to, after detachment, pick up the electronic component 100 on one side with the pick-up tool 110, and subsequently place the electronic component 100 on a carrier 108.

[0130] Thus, the embodiment of Fig. 11 only a single pick-up tool 110 and uses two temporary carriers 112, 112'. Due to the reassembly (e.g., relamination) of the electronic components 100 from the temporary carrier 112 to the further temporary carrier 112', the back of the electronic components 100 (which are to be attached to the carrier 108 according to a specific application) is already on the correct side, so that a single pick-up tool 110 is sufficient.

[0131] As an alternative to Fig. 11, it is also possible that the adhesive base structure 112 shown is structured to have gaps between adjacent electronic components 100.

[0132] Fig. 12 and Fig. 13 show various views of structures obtained during the execution of a method according to an exemplary embodiment. In particular, it may be possible to use a UV-sensitive adhesive for all processes (in particular, singulation and die attachment).

[0133] Referring to Fig. 12, a soft adhesive 188 may be applied to an abrasive substrate 184 (e.g., made of glass) with a laser ashing layer 186 therebetween. A wafer 116 with pads 117, 118 on a front side thereof may be mounted on the soft adhesive 188. A backside metallization layer 190 may be formed on top of the wafer 116.

[0134] Referring to Fig. 13, a plurality of electronic components 100 are mounted with pads 117, 118 on the front side and a pad 119 on the back side on an adhesive base structure 102 which is already patterned to form individual mounting sections 150, one for each electronic component 100.

[0135] Advantageously, the reassembly of the electronic components 100 onto the UV-sensitive adhesive on the temporary carrier 112' can be performed. The separation can be accomplished by means of a laser treatment and / or a mechanical treatment. The thickness of the UV adhesive can be in a range of 0.5 µm to 15 µm, which can be possible in all embodiments. A pick-and-place process can be performed using a pick-up tool 110. Laser-assisted detachment of the electronic components 100 can be performed.

[0136] In the case of an unstructured backside metal, a UV-sensitive material can be spun onto the backside of the wafer before reassembly on a tape.

[0137] Fig. 14 and Fig. 15 show various views of structures obtained during the execution of a method according to an exemplary embodiment.

[0138] Referring to Fig. 14, it may be possible to use only a UV-sensitive adhesive for die attachment. Re-mounting onto the tape can be done using the UV-sensitive adhesive.

[0139] Referring to Fig. 15, a dicing tape can be used as a temporary carrier 112. A pick-and-place process can be performed using flip tools with laser detachment. Direct transfer of an electronic component 100 can be accomplished with laser detachment.

[0140] In the case of an unstructured backside metal, a UV-sensitive material can be spun onto the backside of the wafer before re-assembling it onto a tape.

[0141] Fig. 16 to Fig. 21 show various views of structures obtained during the execution of a method according to an exemplary embodiment.

[0142] In particular, this embodiment relates to a batch die transfer process. Such a process can be particularly advantageous for thin dies, for example, for electronic components with a thickness of less than 200 µm, especially less than 100 µm. The described embodiment implements laser detachment in combination with pitch adjustment.

[0143] Generally, ultra-thin dies must be transferred from a wafer to a substrate using low-impact and low-effort procedures because their small thickness makes them vulnerable to damage. Diffusion soldering can provide superior Rth and Ron properties of the resulting packages. It can also prevent tilting and is compatible with many chip and packaging technologies (e.g., lead frame, PCB embedding, lead frame embedding, embedded die in mold compound). Especially for ultra-thin dies, diffusion soldering can provide reduced solder thickness and prevent solder creepage at a die edge. However, conventional dicing foil adhesion and variations of this parameter do not adequately match the fragility of thin dies during pick-up.Diffusion soldering can be slow and costly when performed on a heated substrate (for example, at a temperature of 360 °C) and for each die individually in a serial process. During processing, the dies can be ground and backside sputtered onto a glass carrier. They can then be transferred to a dicing tape and separated. In a backend, they can be sequentially picked and placed on lead frames. However, the pick-and-place process can be slow. In addition, the process can result in reduced chip thickness and increased brittleness, for example, in electronic components based on silicon carbide (SiC) technology. Poor control of dicing tape adhesion can lead to pick-up problems. This problem can become more severe with increasingly thin chips.

[0144] To overcome at least some of the aforementioned and / or other disadvantages, the embodiment of Fig. 16 to Fig. 21 isolated dies are laser transferred to another carrier with the following properties: Pitches (e.g., in one or two perpendicular directions in the horizontal plane) at wafer and carrier level can be different. The pitches (e.g., in one or two perpendicular directions in the horizontal plane) on the carrier can be identical to the pitches on a, e.g., permanent, carrier (e.g., a leadframe, DCB, etc.) in both directions in the horizontal plane. Intermediate carrier material can be implemented that is stable at temperatures for batch diffusion soldering (e.g., stable at least up to 220°C, or even up to 250°C or more). The intermediate carrier material can be sticky to hold the die in place during transport and during positioning on a leadframe or similar.The carrier and the adhesive material can be removed without residue after batch soldering.

[0145] An embodiment of the process is described in more detail below: The starting point can be the structure which is Fig. 16, which corresponds to the structure shown in Fig. 4, so that for the purpose of consistency the description of Fig. 4 and Fig. 5. A glass substrate 112 used for grinding and dicing has a base structure 102 thereon made of a photopolymer adhesive. Grinding, backside preparation, and dicing on the glass substrate 112 can be performed as described above. The adhesive medium of the base structure 102 can be an adhesive with a light-to-heat conversion (LTHC) release coating. The transparent substrate 112 can be a glass substrate.

[0146] Referring to Fig. 17, the base structure 102 is irradiated with electromagnetic radiation 104 emitted by an electromagnetic radiation source 106 (for example, a laser source) to detach the electronic components 100 from the temporary carrier 112 by at least partially dissolving the base structure 102 or by converting the base structure 102 into a non-adhesive state. Another temporary carrier 112' is arranged beneath the detached electronic components 100, such that the detached electronic components 100 are attached to another base structure 102 on the another temporary carrier 112'. Consequently, reassembly of the electronic components 100 on the transparent carrier 112' with a photopolymer interface structure 102 is accomplished. This can bring the pads 117 to 119 of the electronic components 100 into a desired alignment.If this is not necessary or desired, the process can be performed by . Fig. 17 should be omitted.

[0147] Fig. 17 also shows a pitch, b, ie, a characteristic center-to-center distance between adjacent electronic components 100 or functional portions thereof, corresponding to a wafer level. As in Fig. 17, different electronic components 100 may have different sizes and / or a different number of pads 117 to 119.

[0148] Referring to Fig. 18 is the lower section of the structure, which in Fig. 17 (with identical electronic components 100, which are shown in Fig. 18) are rotated from top to bottom so that another temporary support 108' is arranged beneath the mounted electronic components 100. The further temporary support 108' may be made of a high-temperature-resistant material, for example, a metal plate. Under the control of a control unit 124, an alignment unit 122 may move the temporary supports 112', 108' relative to each other for alignment purposes, or more precisely, for pitch adjustment.

[0149] More specifically, a high-temperature-resistant soft and sticky layer 131 made of a material that can be removed without residues can be arranged on the further temporary carrier 108', which faces the electronic components 100 that are attached to the base structure 102 of the temporary carrier 112'.

[0150] In the arrangement shown and described, it may be possible to detach at least a portion of the base structure 102 by irradiating it with electromagnetic radiation 104 from an electromagnetic radiation source 106. This may be accomplished to detach the electronic components 100 from the temporary carrier 112' in order to transfer the plurality of electronic components 100 to the further temporary carrier 108'. For example, the electronic components 100 may fall downward under gravity onto the soft and sticky layer 131 on the further temporary carrier 108'. Advantageously, this transfer of the electronic components 100 from the temporary carrier 112' to the temporary carrier 108' may be performed with an increased pitch B>b of the electronic components 100 on the temporary carrier 108' compared to the previous pitch b of the electronic components 100 on the temporary carrier 112'.In short, pitch adjustment may adjust the component-to-component spacing of the electronic components 100 to match a pitch B of the permanent supports 108, as shown in FIG. Fig. 19 is shown.

[0151] Thus, a laser-assisted high-speed transfer of dies to the intermediate carrier 108' with the adhesive medium can be accomplished with on-the-fly pitch adjustment. Consequently, reassembly of the electronic components 100 on the heat-resistant carrier foil assembly 108', 131 can be performed with a changed pitch B. The changed pitch B corresponds to a lead frame pitch (see Fig. 19).

[0152] Referring to Fig. 19, the permanent supports 108, which are embodied here as ladder frame structures, are arranged on top of the structure, which is on the lower side of Fig. 18. The permanent supports 108 are aligned with the electronic components 100 on the support 108' in accordance with the changed pitch B. In other words, the pitch B of the electronic components 100 on the temporary support 108' may be identical to the pitch B of the permanent supports 108. The lead frame structures shown in Fig. 19 as permanent supports 108 can be substituted in other embodiments by other permanent supports 108, for example DBC, AMB, IMS, PCB, a laminate.

[0153] Although not shown, a solder layer may be formed on a surface of the permanent supports 108 facing the electronic components 100 and / or on a surface of the electronic components 100 facing the permanent supports 108. Such a solder layer may be configured for diffusion soldering and may be made of NiSn, for example.

[0154] Although this is Fig. 19, it may alternatively be possible to rotate the temporary carrier 108' with the attached electronic components 100 from top to bottom, and arrange the permanent carriers 108 beneath the electronic components 100 on the temporary carrier 108'. Thus, in an alternative embodiment, optional reassembly for an upside-up arrangement can be performed. Batch diffusion soldering can then be performed with the intermediate carrier 108' on top.

[0155] Referring to Fig. 20, hot plates 135, 137 above and below the structure of Fig. 19, for applying mechanical pressure and providing heat. Consequently, all electronic components 100 are connected to an associated permanent carrier 108 by diffusion soldering. This transfers the plurality of electronic components 100 from the further carrier 108' to the permanent carriers 108. This is accomplished by simultaneous or batch diffusion soldering under the application of pressure and heat provided by the hot plates 135, 137. Advantageously, this results in batch diffusion soldering.

[0156] Referring to Fig. 21, the temporary carrier 108' and the soft and sticky layer 131 can be removed from the resulting packages 158 without leaving any residue.

[0157] In an abstract formulation, the embodiment of Fig. 16 to Fig. 21 a method comprising irradiating at least a portion of an adhesive base structure 102 on a temporary carrier 112, 112' with electromagnetic radiation 104 to thereby detach a plurality of electronic components 100 from the base structure 102 in order to transfer the electronic components 100 to another carrier 108' with a modified pitch b->B. The method further comprises subsequently transferring the electronic components 100 to one or more permanent carriers 108 in accordance with the modified pitch B, and batch soldering the electronic components 100 onto the one or more permanent carriers 108.

[0158] In an abstract formulation, the embodiment of Fig. 16 to Fig. 21 an apparatus 120 comprising an electromagnetic radiation source 106, which is configured to irradiate an adhesive base structure 102 on a temporary carrier 112, 112', on which a plurality of electronic components 100 are mounted, in order to thereby detach the electronic components 100 from the base structure 102. The apparatus 120 further comprises an alignment unit 122, which is configured to align a mutual position between, on the one hand, a further carrier 108' for carrying the electronic components 100 and, on the other hand, the detached electronic components 100, in order to transfer the electronic components 100 to the further carrier 108' with the changed pitch B.The alignment unit 122 may be further configured to align the further carrier 108' with one or more permanent carriers 108, to subsequently transfer the electronic components 100 to and connect the electronic components 100 to the one or more permanent carriers 108 in accordance with the changed pitch B.

[0159] The soft and sticky layer 131 can be embodied as a tacking film to support the batch diffusion soldering process. Thus, the soft and sticky layer 131 can be a film with a tacking surface. Corresponding adhesive forces can be, for example, van der Waals forces. The soft and sticky layer 131 can be, for example, silicon-based, can comprise cellophane, etc. The soft and sticky layer 131 can be a film applied to the hard carrier 108' (which can be flat or a roll) or in a frame.

[0160] Various alternatives to the design of Fig. 16 to Fig. 21 can be implemented. For example, the electronic components 100 can be mounted on the permanent carrier(s) 108 in a source-down configuration. A relamination step can be omitted in such an embodiment, and a photopolymer can be formed on the abrasive carrier. In one embodiment, a double delamination can be performed.

[0161] In yet another embodiment, a pitch change may take place during the first re-mounting of the glass carrier (for example, such that the processing according to Fig. 17 can be omitted, and the process with Fig. 18). For example, this can be accomplished by means of a photopolymer on the first carrier.

[0162] Furthermore, alternative connections between the electronic components 100 and the permanent carriers 108 are possible, for example, an adhesive connection (e.g., chips with an adhesive deposit), a soft solder (e.g., using tin, silver, lead), a sintered material (e.g., using silver and / or copper), a copper-copper connection (e.g., formed by hybrid bonding or by ultrasonic welding), etc.

[0163] Still on the embodiment of Fig. 16 to Fig. 21, a process is disclosed which includes: - Thinning a wafer on a first carrier (see Fig. 16) - Separating the dies from the wafer (this can be done at several stages, see for example Fig. 16) - Transferring the dies to a second transparent carrier with a layer that can be photoactivated (see Fig. 17) - Transferring the dies to a third carrier capable of withstanding the process temperatures of a backend process by evaporating the photocomponent of the layer using a laser and changing the pitch to the backend requirements (see Fig. 18) - Alignment of the permanent carriers (for example substrates) to the dies on the third carrier (see Fig. 19) - Joining the dies and the permanent carriers using a hot process (see Fig. 20) - Remove the third carrier (see Fig. 21).

[0164] Optionally, for multi-chip products, it may be possible to transfer different chip types to the third carrier. For example, it may be possible to transfer the chips to the carriers for direct encapsulation.

Claims

[1] A method comprising: • Mounting a plurality of electronic components (100) on associated parts of an adhesive base structure (102) on a temporary carrier (112, 112'); and • Detaching the parts of the base structure (102) by irradiating the parts of the base structure (102) with electromagnetic radiation (104) in order to thereby detach the electronic components (100); • Transferring the electronic components (100) to and batch soldering the electronic components (100) onto one or more permanent supports (108). [2] The method of claim 1, wherein the electronic components (100) are connected to the at least one permanent carrier (108) by batch diffusion soldering. [3] The method of claim 1, wherein the electronic components (100) are bonded to the at least one permanent carrier (108) by means of an adhesive medium on a major surface of the at least one carrier (108), the adhesive medium being at least one of an adhesive solder paste, an adhesive sintering paste, and an adhesive. [4] The method according to any one of claims 1 to 3, wherein the method comprises dissolving the at least part of the base structure (102) such that the base structure (102) is converted from a component-bearing solid state to a component-releasing dissolved gaseous and / or liquid state. [5] The method according to any one of claims 1 to 4, wherein the method comprises irradiating the base structure (102) with an electromagnetic radiation source (106) configured as a laser to thereby detach the electronic component (100). [6] The method according to any one of claims 1 to 5, wherein the method comprises aligning a mutual position between, on the one hand, a carrier (108, 108') for carrying the electronic component (100) and, on the other hand, the detached electronic component (100) so that the electronic component (100) is transferred to and lands on the carrier (108, 108'). [7] The method according to any one of claims 1 to 6, wherein the method comprises releasing the at least a portion of the base structure (102) while the electronic component (100) is disposed on a bottom side of the adhesive base structure (102). [8] The method according to any one of claims 1 to 5, wherein the method comprises detaching the at least a portion of the base structure (102) while the electronic component (100) is disposed on a top surface of the adhesive base structure (102). [9] The method according to claim 8, wherein the method comprises, after the detaching, picking up the electronic component (100) at one side thereof by means of a picking tool (110), in particular a suction type picking tool, and subsequently placing the picked up electronic component (100) on a carrier (108). [10] The method according to claim 9, wherein the method comprises, after picking up, further picking up the electronic component (100) on an opposite other side thereof by means of another picking tool (110'), in particular another suction-type picking tool, and subsequently placing the electronic component (100) with said one side on the carrier (108), wherein the method in particular comprises prior to picking up, attaching the electronic component (100) to an opposite other side of a temporary support (112'), and after picking up, placing the picked up electronic component (100) with the other side on the carrier (108). [11] The method according to any one of claims 1 to 10, wherein the method comprises detaching the at least part of the base structure (102) by irradiating with electromagnetic radiation (104) to thereby detach a plurality of electronic components (100) in order to transfer the plurality of electronic components (100) to a further carrier (108') with a changed, in particular enlarged, pitch (B) compared to another pitch (b) of the plurality of electronic components (100) on the temporary carrier (112, 112'). [12] The method according to claim 11, comprising at least one of the following features: wherein the further carrier (108') is a further temporary carrier; wherein the further carrier (108') is a high-temperature-resistant carrier, in particular is temperature-resistant at least up to 220 °C and / or is a metal carrier; wherein the method comprises Arranging a soft and sticky layer (131), in particular a high-temperature-resistant layer, further in particular temperature-resistant at least up to 220 °C, between the plurality of electronic components (100) and the further carrier (108'); wherein the method comprises Transferring the plurality of electronic components (100) from the further carrier (108') to one or more permanent carriers (108), in particular by applying pressure and heat. [13] The method according to any one of claims 1 to 12, comprising at least one of the following features: wherein the method comprises Mounting the electronic component (100) on the adhesive base structure (102) on an optically transparent temporary carrier (112, 112'), and Irradiating the base structure (102) with electromagnetic radiation (104) through the optically transparent temporary carrier (112, 112') to release at least a part of the base structure (102); wherein the method comprises irradiating the base structure (102) by scanning the base structure (102) by means of an electromagnetic radiation source (106) by moving, on the one hand, the electromagnetic radiation source (106) and / or an electromagnetic radiation beam thereof and, on the other hand, the base structure (102) relative to each other; wherein the method comprises irradiating the base structure (102) through a partially optically transparent and partially opaque mask (114) which is arranged between the base structure (102) and the electromagnetic radiation source (106), in particular a grayscale mask which is configured to irradiate a portion of the base structure (102) corresponding to an edge of the electronic component (100) with a higher intensity than another portion of the base structure (102) corresponding to a center of the electronic component (100). [14] The method of any one of claims 1 to 13, wherein the method comprises thinning and then separating a wafer (116) into a plurality of electronic components (100) while the wafer (116) is disposed on the adhesive base structure (102). [15] The method of claim 14, wherein the method comprises, after thinning and before separating, forming pads (119) on a thinned surface of the wafer (116). [16] Apparatus (120) comprising: • an electromagnetic radiation source (106) configured to irradiate at least one mounting portion (150) of an adhesive base structure (102) on a temporary carrier (112, 112'), on which mounting portion (150) an electronic component (100) is mounted, to thereby detach the electronic component (100) from the mounting portion (150); and • an alignment unit (122) for aligning a mutual position between, on the one hand, a carrier (108, 108') for carrying the electronic component (100) and, on the other hand, the detached electronic component (100), so that the electronic component (100) is transferred to and lands on the carrier (108, 108'); • wherein the apparatus (120) is configured for batch soldering a plurality of the electronic components (100) to one or more permanent supports. [17] The apparatus (120) according to claim 16, comprising one of the following features: wherein the apparatus (120) is configured such that the detached electronic component (100) falls downwards by means of gravity, so that the downwardly falling electronic component (100) lands on the carrier (108, 108'); wherein the apparatus (120) is configured such that the detached electronic component (100) is transferred by means of gas pressure, or by means of gravity, or an expansion of the base structure (102) or an intermediate layer such that it lands on the carrier (108, 108'); wherein the apparatus (120) comprises the adhesive base structure (102) configured to release when irradiated with electromagnetic radiation (104); wherein the apparatus (120) comprises the adhesive base structure (102) configured to be converted from an adhesive state to a non-adhesive or less adhesive state when irradiated with electromagnetic radiation (104); wherein the electromagnetic radiation source (106) comprises a laser. [18] The apparatus (120) according to any one of claims 15 to 17, comprising one of the following features: wherein the alignment unit (122) is configured to statically place a vertically downwardly falling electronic component (100) in lateral alignment with the statically placed carrier (108, 108') such that the vertically downwardly falling electronic component (100) lands on the carrier (108, 108'); wherein the alignment unit (122) is configured to dynamically move the electronic component (100) and the carrier (108, 108') relative to each other along a lateral direction transverse to gravity, such that a downwardly falling electronic component (100) lands on the carrier (108, 108') taking the lateral movements into account. [19] The apparatus (120) according to any one of claims 15 to 18, comprising a control unit (124) configured to control the electromagnetic radiation source (106) to perform the irradiation and the alignment unit (122) to perform the alignment. [20] The apparatus (120) according to any one of claims 15 to 19, comprising at least one of the following features: comprising the carrier (108) having an adhesive medium (126) on a main surface at which the landing electronic component (100) is stopped, wherein in particular the adhesive medium (126) comprises at least one of an adhesive solder paste, an adhesive sintering paste, and an adhesive; comprising the carrier (108') which is a high-temperature-resistant carrier covered with a high-temperature-resistant soft and sticky layer (131); comprising the electronic component (100) having pads (117, 118, 119) on both opposite main surfaces and / or experiencing a vertical current flow during operation; wherein the apparatus (120) is configured to control the irradiation of at least the mounting portion (150) of the adhesive base structure (102) with electromagnetic radiation (104), thereby detaching a plurality of electronic components (100) from the mounting portion (150) in order to transfer the plurality of electronic components (100) to the carrier (108, 108') with a changed, in particular enlarged, pitch (B) compared to another pitch (b) of the plurality of electronic components (100) on the temporary carrier (112, 112').

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