Method for converting a structure from an actual state into a target state, arrangement consisting of a substrate and a reaction layer, and apparatus for carrying out such a method

Abstract

The invention relates to a method for transferring a structure (2', 2), which is arranged on a substrate (1, 1') and / or which is embedded in the substrate (1, 1'), from an actual state into a target state, in particular before further processing, e.g. singulation or accommodation into a substrate holder (6), or / or before and / or during a bonding of substrates (1, 1'), comprising: - Providing a substrate (1, 1') having at least one structure (2', 2) in the actual state, - Providing at least one reaction layer (5r) which is integrated in particular into a layer system (3), - Implementing an operative connection between the at least one reaction layer (5r) and the substrate (1, 1') in such manner that a state of change in the at least one reaction layer (5r) causes a deformation in the substrate (1, 1'), - Triggering the state of change in the at least one reaction layer (5r) by means of an influencing means (8), wherein the state of change in the at least one reaction layer (5r) is induced in a locally limited manner such that the structure (2', 2) is transferred from the actual state into the target state.

Description

[0001] ■□I

[0002] Erich Thallner MSP Reference: 42323 PT-WO PM / SK

[0003] Method for converting a structure from an actual state to a target state, arrangement of substrate and reaction layer and device for carrying out such a method.

[0004] The present invention relates to a method for transforming a structure from an actual state to a desired state, an arrangement of substrate and reaction layer and a device for carrying out such a method.

[0005] In recent years, it has become necessary to develop increasingly complex methods for aligning and bonding substrates. One of the most important bonding methods is fusion bonding. Fusion bonding is a type of direct bonding. The substrate surfaces of two substrates are directly bonded together.

[0006] This bonding process has made it possible in recent years to stack substrates with functional units of varying functionality on top of each other. This enabled a three-dimensional structure. Simultaneously, it increased the packing density and, for the first time, made it possible to produce dies or composite chips or chiplets. This concept is known as heterogeneous integration.

[0007] One approach to heterogeneous integration is to use a wafer-to-wafer (W2W) process. In this process, two substrates, specifically wafers, are aligned and bonded to each other. Each substrate contains a correspondingly large number of functional units. The main challenge lies in ensuring that all functional units of the first substrate are correctly aligned and bonded to the functional units of the second substrate. This alignment is usually achieved using alignment marks or contact points, particularly through silicon vias (TSVs) of the respective functional units.

[0008] A second possibility for heterogeneous integration is to use a C2W (chip-to-wafer) method. In this method, a single functional @

[0009] A unit, in particular a plate, a chip or a chiplet, is aligned and bonded to a substrate or other isolated functional unit already located on a substrate using a C2W bonder.

[0010] The biggest problem, and thus a task of this invention, is that, in general, neither the substrates nor the individual functional units can be manufactured without defects, in particular without distortion, or they change during other process steps and deviate from the desired target shape, i.e., more generally, a target state. These deviations may only be in the micrometer or even nanometer range, but nevertheless have an impact on the bond quality and thus on the throughput.

[0011] The present invention solves the problem with a method according to claim 1, with an arrangement according to claim 14, and with a device according to claim 15. Advantageous embodiments of the invention are specified in the dependent claims. The scope of the invention also includes all combinations of at least two features specified in the description, in the claims, and / or in the drawings. Where specified value ranges are given, values ​​lying within the stated limits are also considered disclosed limits and may be claimed in any combination.

[0012] According to a first aspect of the present invention, a method is provided for transferring a structure arranged on and / or embedded in a substrate from an actual state to a desired state, in particular before further processing, such as singulation or pickup by a substrate holder, and / or before and / or during bonding of substrates, comprising:

[0013] Providing a substrate with at least one structure in its current state, providing a reaction layer, in particular integrated into a layer system,

[0014] Realizing an active connection between the at least one reaction layer and the substrate, wherein the active connection is designed such that a change state in the at least one reaction layer causes a deformation in the substrate,

[0015] Triggering the change state in the at least one reaction layer by means of an influencing agent, @ wherein the change state in the at least one reaction layer is locally limited in such a way that the structure is transformed from the actual state to the target state.

[0016] In contrast to the prior art, this approach proposes transforming a non-ideal substrate with a structure in its existing state into a desired target state through actively induced rectification. A reaction layer is used for this purpose, preferably integrated into a layer system. The reaction layer or the layer system is preferably located on and / or within the substrate. In other words, it is proposed to reverse an undesired distortion by acting on the reaction layer, i.e., to rectify or distort the structure in or on the substrate. It proves particularly advantageous that the influencing agent does not act on the substrate but on the reaction layer. This also avoids or reduces any negative impact of the influencing agent on the substrate.

[0017] In particular, a substrate or a substrate stack can have more than one layer system. It is conceivable that a first layer system is located on the back side of a substrate and that global, strong active compounds are generated via this layer system, while a further layer system located on the opposite side of the substrate, particularly near structures, allows the generation of local active compounds. Preferably, the substrate comprises a layer system formed on the back side of the substrate and / or a further reaction layer, particularly as part of another layer system or as a single layer, which is spaced from the back side and, for example, arranged within the substrate. The back side of the substrate faces the side with the structure.Preferably, the ratio between the distance to the back side and the total thickness of the substrate is established for the further reaction layer, which assumes a value between 0.2 and 0.87, preferably between 0.3 and 0.87 and particularly preferably between 0.5 and 0.87.

[0018] In special embodiments, the reaction layer is located less than 50 pm, preferably less than 25 pm, most preferably less than 1 pm, most preferably less than 500 nm, and most preferably less than 100 nm away from the structures to be influenced.

[0019] The subsequent layer system is thus positioned close to the surface of the structure without directly contacting it. Using a manipulation method, such as a laser and / or an electric field, the reaction layer is locally altered physically and / or chemically at desired locations, resulting in a correction that restores the substrate to its target state. This achieves the creation of a desired target state. For the first time, this makes it possible to precisely and permanently adjust deviations in the micrometer and / or nanometer range between the actual and target states, thus providing an ideal starting point for further processing steps. In particular, this method yields substrates that represent an ideal starting point for fusion bonding.

[0020] In particular, it may be desirable to set the target state of a structure so that its features, i.e., certain properties such as a geometric shape, are identical to features of a structure already present on the substrate, even if the structures themselves appear distorted in relation to a rectangular coordinate system. The target state, therefore, always refers to a desired state, which does not necessarily represent a theoretical optimal state. The target state serves, in particular, the purpose of ensuring the reliability of a subsequent process. For this to be achieved, the structure must assume a state that is meaningful for the subsequent process, which may in turn depend on other features or properties that are not present on the substrate itself, but rather on another substrate or a tool.In such cases, even the theoretical optimal state may be unsuitable, as it does not take into account a deviation from the optimal state of the other characteristic.

[0021] The functional connection between the reaction layer and the substrate can be direct or indirect, for example, via an intermediate layer. It is conceivable that a functional connection between the substrate and the reaction layer exists via a bond. It is also conceivable that the reaction layer has grown on the substrate, for example, by means of epitaxy. In particular, the functional connection is designed to transmit mechanical stresses and / or shear forces to the substrate. It is especially preferred that the reaction layer acts on the outer surface or side surface opposite the structure. In other words, the deformation caused by the reaction layer on a side opposite the structure is transmitted via the substrate and leads to a stress-relieving effect on the side surface where the structure is located.The substrate thus transmits the deformation caused by the reaction layer. This also applies analogously to a further reaction layer that is arranged within the substrate.

[0022] The effective distance of the reaction is preferably as small as possible. In particular, the effective distance is less than 1 mm, preferably less than 1 pm, and even more preferably less than 1 nm. This preferably small effective distance is achieved by positioning the layer system, and especially the reaction layer, as close as possible to the substrate surface to be modified. The reaction in the reaction layer can lead to elastic and / or plastic deformation along the effective connection. Elastic deformation is preferred. A suitable choice of substrate, especially its thickness, enables precise control of the deformation while simultaneously protecting the substrate and the structure. Advantageously, the reaction layer, particularly in the form of a solution layer, can also be embedded in materials that possess sufficient elasticity and thus allow deformation (without brittle fracture) even if the reaction layer is partially destroyed.In particular, it is provided that the distance between the layer system or the reaction layer and the structure is less than 50 pm, preferably less than 25 pm, even more preferably less than 1 pm, most preferably less than 500 nm and most preferably less than 100 nm.

[0023] To determine the position and required intensity with which the reaction layer acts on the substrate, or with which the influencing agent acts on the reaction layer, the person skilled in the art preferably uses empirical data and / or simulations that also take into account, for example, the thickness of the substrate and / or the type of bond between the structure and the substrate, or, if applicable, between the reaction layer and the substrate. Preferably, a machine learning algorithm trained on test data is used to determine the intensity, extent, position, and / or type of influence exerted on the reaction layer by the influencing agent. It is also conceivable that different influencing agents are provided and / or used to induce the desired state of change in the reaction layer.

[0024] In particular, after each application of the influencing agent to the reaction layer, preferably even during the application, the substrate surface is measured in order to measure and record the success of the application and, based on this, to improve the application. Preferably, a control loop can be created by combining the observation, especially in-situ, with the application. However, it is also conceivable that the substrate surface is measured only once before the application to the reaction layer and that the application to the reaction layer is controlled solely based on this data, so that no control is necessary.

[0025] In particular, a substrate is understood to be a large-area substrate, especially a wafer. Where a reaction layer is mentioned, it is to be understood as the at least one reaction layer.

[0026] In particular, a locally confined state of change is understood to be one whose lateral extent in a plane parallel to the principal extension plane is smaller than the lateral extent of the structure measured parallel to the principal extension plane. It is preferably provided that the ratio between the lateral extent of the state of change and the lateral extent of the structure assumes a value less than 1, preferably less than 0.8, and most preferably less than 0.6. This allows for targeted counteracting of distortion in specific areas, especially if the distortion does not extend over the entire structure.

[0027] In mechanics, displacement is understood as the difference between the positions of a considered volume element, or in the extreme case, a point, between two different states. A multitude of such displacements for different spatial positions results in a displacement field.

[0028] Distortion is defined as the change in displacement with respect to location. Therefore, if the displacement of a body along a line is always constant, its distortion along that line is zero.

[0029] In this context, a strict distinction between displacement and distortion will no longer be made unless explicitly stated. The aim is always to create a desired state from the current state. However, these terms are familiar to those skilled in the art of elasticity theory. The substrate to be corrected can also be understood as a product substrate, since functional units for a final product are preferably produced on it. Preferably, the change in the at least one reaction layer is achieved by locally altering the volume and / or lattice structure within the at least one reaction layer and / or by generating a locally confined gas bubble within the at least one reaction layer. In one embodiment, the action of the influencing agent causes a volume change, i.e., a volume contraction or volume expansion, of the layer. Preferably, the volume change occurs through thermal expansion.

[0030] Another possibility is that heat input from the influencing agent causes a reaction layer to expand significantly, thereby generating internal stresses that in turn plastically deform another reaction layer. The individual reaction layers can thus influence each other. By correctly selecting and / or sequencing the appropriate reaction layers, the layer system itself becomes a crucial factor in the success of the equalization process through the application of an influencing agent.

[0031] It is also conceivable that the reaction layer is subjected to an electric and / or inductive magnetic field, thus inducing a change in the reaction layer. Mechanical action on the reaction layer is also conceivable, for example, via vacuum fixation. In one embodiment, the action of the influencing agent causes a solid-state phase transformation. This solid-state phase transformation can be accompanied by a change in volume.

[0032] In one embodiment, the action of the influencing agent causes a phase transformation through melting and / or solidification. The influencing agent facilitates a transition from the solid to the liquid phase. In particular, by selecting a suitable layer combination, an alloy can be created that, upon solidification, again undergoes a volume change. By selectively choosing the alloying elements in the different layers of the layer system, it is possible to control volume contraction or expansion, depending on whether the resulting alloy has a smaller or larger molar volume than the phases of the individual layers. However, the phase transformation to a melt can itself produce the desired volume contraction or expansion, achieving the desired effect.

[0033] In one embodiment, the action of the influencing agent causes a phase transformation through sublimation and / or resublimation. A local, spontaneous sublimation of the solid material is conceivable, followed by bubble formation, particularly gas bubble formation. The resulting gas bubble can, for example, be confined to a local area by overlying and / or underlying layers that are less sensitive to the influencing agent. In particular, the gas bubble formation is accompanied by a change in volume, preferably an increase in volume.

[0034] In one embodiment, the influence of the influencing agent causes a phase transformation between an amorphous and a crystalline phase. Preferably, an amorphous phase exists in a metastable state and is crystallized by the influencing agent, in particular a laser beam. However, it is also conceivable that the influencing agent, in particular an ion beam, amorphizes a crystalline phase.

[0035] Furthermore, it is preferably provided that the influencing agent alters a material state, for example, a phase and / or lattice structure change, in the reaction layer. It is also conceivable that partial liquefaction of the reaction layer eliminates shear forces in the liquefied area, while shear forces or mechanical stresses persist in other areas, thereby generating a new mechanical stress state in the substrate that contributes to or causes the straightening of the structure.

[0036] Preferably, the layer system is formed from at least one reaction layer and at least one release layer. The layer system comprises at least the reaction layer. If, for example, the substrate is bonded to a support substrate, the layer system preferably has at least one release layer that can be used in a subsequent process step to release the substrate from the support substrate. Such a release layer was disclosed, for example, in WO 2023 179 868 A1, the disclosure of which, with regard to the layer system, in particular the release layer, is explicitly referenced here.

[0037] The solvent layer of the layer system preferably comprises at least one material from one of the following material classes: @

[0038] • Dielectric, in particular o Nitrite, in particular

[0039] ■ TiN, CrN, TaN, AIN, NiN, Si3N4o Carbide, especially carbon layers o Carbonitride, especially

[0040] ■ SiCN oxide and / or polymer and / or

[0041] • Electric medium, preferably metal, in particular

[0042] ■ Cr, Al, Ta, Co, Ni, Mn, Fe, Au, Ga, Sn, Ge, W, Cu, In

[0043] All subsequent layers of the layer system serve to generate a physical and / or chemical reaction in order to produce the corresponding equalization. Layers that can induce a physical and / or chemical reaction to produce the corresponding equalization are referred to as reaction layers.

[0044] A particular advantage is that the reaction layer also serves as the solvent layer, meaning that the materials used in the solvent layer can also be considered suitable for the reaction layer. Nitrides, in particular, are especially well-suited for gas bubble formation. However, the range of usable materials for the reaction layer can be further expanded with regard to their physical properties, resulting in additional material classes or materials:

[0045] • Material with a low melting point, for example less than 700°C, preferably less than 500°C, even more preferably less than 300°C, most preferably less than 200°C and most preferably less than 100°C, in particular low-melting metal, in particular

[0046] AI, Sn, In, Ga @

[0047] • Material with a high coefficient of thermal expansion, especially greater than 4x10 -6 1 / K, preferably larger than 10x10-6 1 / K and especially preferably larger than 25x10' 6 1 / K, such as Zn, Al, Sn, Ag, Cu, Au

[0048] Preferably, the layer system comprises several different reaction layers. This advantageously allows for influencing the interaction between the reaction layer and the substrate. Furthermore, it enables greater flexibility in the selection and design of the influencing agent. For example, it is possible to utilize the influence of different influencing agents to induce a preferred and particularly favorable state of change in the reaction layer(s), i.e., in the layer system.

[0049] Each reaction layer can preferably be sequentially activated by an influencing agent. Particularly when using a laser as the influencing agent, achieving selectivity by using a different wavelength and / or intensity and / or pulse length and / or polarization and / or a different focal point is relatively straightforward.

[0050] Each reaction layer can be prestressed by introducing residual stresses. These can be compressive and / or tensile residual stresses, which may be inhomogeneously distributed within the reaction layer or even generated only at specific points.

[0051] Preferably, the influencing agent affects several or all reaction layers simultaneously at one position, i.e., in a locally limited area.

[0052] Preferably, the change state is intended to be temporary. It has been found that for the desired state, it is sufficient if the modified state is maintained only until a further processing step, such as bonding, is performed. This allows for greater flexibility in how the change state is achieved. It does not need to involve permanent plastic deformation. Preferably, the change state is maintained until the further processing is carried out or the bonding is completed. The change state, once initiated, can have a corresponding half-life, i.e.,Although they can generally be terminated independently after initiation, the half-life is large compared to the time span to the next processing step, and / or the change state is maintained by repeated initiation at least until the next further processing step.

[0053] In an improvement of the aforementioned embodiments, a further layer, particularly one that is easily plasticizable, is deposited above the reaction layer. Due to the changes in the reaction layer, the easily plasticizable layer is plastically deformed and can thus retain its deformation even after the removal of the influencing agent. This eliminates the need for any subsequent process or further treatment to occur within a specific time interval.

[0054] Preferably, the reaction layer is continuous beneath the structure or beneath several structures. This allows, for example, the locally limited change state to be initiated at any position beneath the structure(s).

[0055] Preferably, the substrate and the reaction layer are arranged on a support substrate and / or a substrate holder. This presents corresponding challenges for the influencing agent. Accordingly, the support substrate and / or the substrate holder are adapted to the influencing agent. For example, a suitable material is selected to allow a certain degree of transparency. It is also conceivable that a two-dimensional arrangement of heating elements is formed in the substrate holder, with which the reaction layer can be selectively thermally influenced.

[0056] In particular, it is provided that light from a laser source and / or an electric field is used as the influencing agent. It is preferably provided that the light is guided through a substrate holder that is at least partially transparent, preferably completely transparent, and / or a support substrate that is at least partially transparent, preferably completely transparent.

[0057] If the substrate holder and / or the support substrate and / or the product substrate is a silicon substrate, then the laser wavelength should be between 1 pm and 10 pm, as silicon has a very high transmittance (transmittance) of up to 50% in this wavelength range. If other substrates are chosen, it may be necessary to select a laser with a different wavelength. A further advantage of this sophisticated process is that, ideally, neither the product substrate nor the support substrate is damaged.

[0058] In particular, it is provided that laser light, especially pulsed laser light, is used for separation. The laser light preferably lies in the infrared or ultraviolet region of the electromagnetic spectrum. In a preferred embodiment of the method, the laser beams have a wavelength between 0.1 pm and 500 pm, preferably between 0.2 pm and 100 pm, more preferably between 0.3 pm and 50 pm, most preferably between 0.5 pm and 10 pm, and most preferably between 1 pm and 2.5 pm. In this way, the separation layer can be irradiated particularly efficiently and precisely. The substrate is preferably transparent to the laser beams.

[0059] In a preferred embodiment of the method, the pulse energy of the laser beams is between 0.01 pJ and 128 pJ, preferably between 0.125 pJ and 64 pJ, more preferably between 0.25 pJ and 32 pJ, most preferably between 0.5 pJ and 16 pJ, and most preferably between 1 pJ and 8 pJ. It has been found that damage to the product substrate can be avoided with these pulse energies.

[0060] In a preferred embodiment of the method, the pulse duration of the laser beams is between 1 ps and 1 ps, preferably between 100 ns and 1 ps, more preferably between 1 ns and 1 ps, most preferably between 500 ps and 1 ps, and most preferably between 50 ps and 1 ps. This pulse duration allows for targeted application for separation.

[0061] In a preferred embodiment of the method, the laser cross-sectional area (spot size) is provided to be smaller than 2,000 pm. 2 , preferably smaller than 500 pm 2 , preferably smaller than 80 pm 2 , preferably smaller than 20 pm2, most preferably smaller than 1 pm 2 This is possible. A small laser area can increase the resolution of the effect on the reaction layer.

[0062] In one embodiment, the influencing agent is used to modulate the reaction layer spatially and, preferably, temporally. This allows for different degrees of influence of the influencing agent on the reaction layer, thereby enabling targeted spatial resolution during the transition from the actual state to the desired state. For example, it would be conceivable to use various optical systems, in particular optics and / or adjustable optics (such as two lenses whose distance from each other can be changed), which result in different sizes of the laser spot being projected onto a focal plane, especially a reaction layer. Furthermore, the distance (pitch) between individual spots can be varied. Additionally, the spots can be positioned precisely.One possibility is to simultaneously expose different areas of the reaction layer with multiple beam paths, each preferably processed or manipulated differently to exert a targeted inhomogeneous effect on the reaction layer. This allows for the simultaneous induction of effects of varying magnitudes within the reaction layer. It is also conceivable that properties of the laser light, such as its degree of focus or spot size within the reaction layer, can be modified during a single pass or for different areas of the reaction layer. For example, one or more lenses can be moved to precisely control the extent of the laser light's effect on the reaction layer, particularly with spatial resolution.

[0063] In a preferred embodiment of the method, the distance between the laser beams' areas of effect on the reaction layer is at least 0.1 pm, preferably at least 1 pm, more preferably at least 5 pm, even more preferably at least 10 pm, and most preferably at least 50 pm, so that the laser beam areas do not overlap. This allows for particularly simple and efficient manipulation of the reaction layer and generation of reactions with correspondingly high resolution. In particular, short lever distances or effective distances are achieved, which in turn enables high spatial resolution for deformations. In certain exceptional cases, however, an overlap of the areas of effect may also be desirable.

[0064] The laser is optimized for the lowest possible energy input, so that apart from the desired reaction in the reaction layer, no further damage occurs, in particular no damage to the product substrate.

[0065] The laser parameters can be selected so that only partial disruption occurs in the layer system, particularly in the reaction layer and / or the solution layer. The resulting distortions still lead to deformation of the wafer.

[0066] Another advantage is the low temperature input, particularly for the product substrate. The resulting temperatures are preferentially concentrated within the layer system. In particular, the pulsed and highly focused laser largely prevents a significant temperature increase in the product substrate.

[0067] The influencing agent preferably does not act on the layer system through the substrate surface of the substrate to be distorted, which contains the structures, but rather from the back side. However, if the substrate to be distorted is thin enough and transparent enough for the influencing agent, then influencing the layer system through the substrate to be distorted is conceivable and possible. Arranging the reaction layer on the side surface of the substrate opposite the structure proves particularly advantageous because it simplifies the application of the influencing agent. For example, the structure does not impair the influencing agent. Furthermore, there are fewer limitations with regard to the properties of the substrate, such as its transparency to a specific type of light that is absorbed by the reaction layer to induce the change.

[0068] In particular, it is conceivable that the influencing agent alters the material composition in the at least one reaction layer. For example, a chemical reaction is induced by the influencing agent, such as between materials of adjacent reaction layers or different materials within the same reaction layer. Preferably, an alloy is formed. It is conceivable, for example, that a reaction layer is at least partially, and especially regionally, liquefied by the influencing agent and forms an alloy with the material from another reaction layer through diffusion.

[0069] It is particularly preferred that the change state in the reaction layer is induced by means of a further influencing agent in the material composition. By using a multi-stage process with several influencing agents, flexibility in adapting the excitation state is possible.

[0070] It is conceivable, for example, that an alloy is only formed through the local solid-liquid phase transition determined by the influencing agent, and that this alloy can then be influenced by further influencing agents, particularly electric and / or magnetic fields. Thus, it is conceivable that in a first process step, the influencing agent creates a corresponding alloy at well-defined positions, which, in subsequent process steps, then causes a contraction or expansion due to its phase properties.

[0071] For example, it is provided that the substrate is at least partially bonded to a larger substrate, particularly via the structure. Preferably, it is provided that the substrate is bonded to a further substrate, with the structure being transformed from its current state to the desired state during the bonding process.

[0072] The method is preferably applied before further processing of the substrate. However, for large-area substrates, especially wafers, a particularly preferred embodiment allows the method to be applied during a bonding process. By applying the method during bonding, displacements or distortions caused by the bonding process itself, particularly by the movement of the bonding wave, can be actively compensated by introduced distortions. It is also conceivable to apply the method before bonding to prepare the substrate for bonding. In particular, the method is applied to two substrates to be bonded together before the bonding process. The two target states resulting from the actual states are preferably identical after the method has been applied to both substrates.

[0073] A further object of the present invention is an arrangement comprising a substrate with a structure in its current state and at least one reaction layer, in particular integrated into a layer system, for carrying out a process according to the invention. All advantages and properties described for the process can be transferred analogously to the arrangement and vice versa.

[0074] A further object of the present invention is a device for carrying out the method according to the invention, wherein the device comprises at least one influencing means. All advantages and properties described for the method according to the invention can be transferred analogously to the device and vice versa.

[0075] The following describes a process as it is carried out in a semiconductor factory (fab).

[0076] In a first process step, data describing the current state of a substrate are measured and provided. This provision can be done via software and / or hardware. The data preferably consists of position and / or displacement and / or distortion maps, which will subsequently be referred to simply as "data".

[0077] In a second step, the current state is compared with a target state, also stored in a computer. The target state is likewise represented by data.

[0078] In a third process step, the necessary processing steps will be calculated and determined in order to achieve the desired current state.

[0079] In a fourth process step, the system as described here and the described method for transitioning the substrate from its current state to the target state are used to bring the current state as close as possible to the desired target state. Tolerance and threshold values ​​are permitted. The process does not necessarily have to be carried out until the current state perfectly matches the target state, but it should come as close as possible. The goal is to minimize deviations between the target and current states. In this process step, in-situ observation of the current state is optional. It is possible that the device generating the distortions does not have the necessary monitoring equipment to track the current state. In this case, the process is more controlled than regulated. Advantageously, however, the device has an optical system for in-situ observation.

[0080] In a fifth, optional step, the newly achieved current state can be measured again. This measurement can be performed with a different device and / or method, in the same device / cluster where the previous steps were carried out, in a different device / cluster, or even in a different country.

[0081] In a sixth, optional step, the current state is compared again with the target state. From this point onward, a decision is made whether to proceed back to the first step. If the process continues from the first step, a loop is initiated that only ends when the result of the sixth step is satisfactory. This loop can therefore be executed multiple times.

[0082] In a seventh process step, the substrate, now brought to the desired target state, is processed using a different method. For example, a bonding process could be carried out with a second substrate that has also undergone this process.

[0083] In an eighth process step, the result of the seventh process step is verified and evaluated. Since the substrate stack thus generated can be further processed, it is necessary to restart the process at the first three steps, depending on how much data about the substrate stack or the substrate is already available.

[0084] The device can also be part of a plant system. A plant system consists of at least one cluster, which in turn consists of at least one device.

[0085] In a first embodiment, the plant system consists of only a single cluster.

[0086] • Cluster

[0087] • Surveying device

[0088] • Device for transferring the substrate from its current state to its target state

[0089] • Bonding device or other device for carrying out further process steps

[0090] • Debonding device

[0091] In this embodiment, all devices are grouped in the same location, in the same cluster.

[0092] In a second embodiment, the plant system consists of three clusters. The clusters can be geographically far apart, particularly in different countries, or located at different positions within a semiconductor plant.

[0093] • Cluster 1 o Measuring device • Device for transferring the substrate from its current state to its target state

[0094] • Cluster 2 o Bonding device or another device for carrying out further process steps

[0095] • Cluster 3 or Debond device

[0096] This embodiment has the same number of devices as the first embodiment, however, the devices are grouped into clusters and these are distributed geographically.

[0097] In a third embodiment, the plant system also consists of three clusters.

[0098] • Cluster 1 o Surveying device

[0099] • Device for transferring the substrate from its current state to its target state

[0100] • Cluster 2 o Bonding device or other device for carrying out further process steps

[0101] • Cluster 3 o Debond device o Surveying device

[0102] The third cluster also has a surveying device.

[0103] In a fourth embodiment, the plant system consists of four clusters.

[0104] • Cluster 1 o Device according to the invention

[0105] • Cluster 2 o Bonding device or other device for carrying out further process steps

[0106] • Cluster 3 o Surveying device

[0107] Cluster 3 o Debond device The tasks of the aforementioned devices are as follows.

[0108] The measuring device is designed to measure a substrate and / or a substrate stack before, during, and / or after any process step. Measurement is preferably performed optically, but can also be performed acoustically or by tactile measurement (AFM).

[0109] The device for transferring the substrate from the actual state to the desired state is understood to be the device described here, which is capable of carrying out the process for transferring the substrate from the actual state to the desired state by means of an influencing agent on a reaction layer.

[0110] A bonding device is a device used for bonding substrates. Colloquially, this device is simply called a bonder.

[0111] A debonding device is understood to be a device with which it is possible to separate a substrate or a substrate stack. The debonding device can, in particular, be identical to the device according to the invention. In this case, the layer system of the substrate or substrate stack would contain not only a reaction layer but also a release layer, or the reaction layer could simultaneously be the release layer at which the separation is carried out.

[0112] Further advantages, features, and details of the invention will become apparent from the following description of preferred embodiments and from the drawings. These show:

[0113] Figure 1 shows a top view of an undistorted substrate in a desired target state,

[0114] Figure 2 shows a top view of a distorted substrate in an undesired state.

[0115] Figure 3 shows a side view of a substrate with a layer system according to an exemplary embodiment of the present invention.

[0116] Figure 4 shows a side view of a substrate with a layer system on a substrate holder. Layer system according to an exemplary embodiment of the present invention.

[0117] Figure 5 shows a side view of a substrate with a layer system on a support substrate layer system according to an exemplary embodiment of the present invention.

[0118] Figure 6 shows a side view of a first embodiment,

[0119] Figure 7 shows a side view of a second embodiment,

[0120] Figure 8 shows a side view of a third embodiment,

[0121] Figure 9 shows a side view of a fourth embodiment,

[0122] Figure 10a shows a side view of a first process step,

[0123] Figure 10b shows a side view of a second process step,

[0124] Figure 10c shows a side view of a third process step and

[0125] Figure 10d shows a side view of a fourth process step.

[0126] In the figures, identical components or components with the same function are marked with the same reference symbols.

[0127] Figure 1 shows a simplified top view of a non-distorted substrate 1, which has several structures 2. These structures 2 can be, for example, functional units such as microchips, MEMS, LEDs, memory chips, etc. However, the structures 2 can also simply be applied distortion markers whose shape indicates whether the substrate surface is distorted in its pure, untreated state. It is conceivable, for example, that distortions are introduced into the substrate during the cutting, grinding, and / or polishing process, distortions that are already present before the processing of functional units even begins. In principle, all types of measurable, especially topographic, structures 2 are conceivable.Figure 1 serves primarily for illustrative purposes and represents an idealized substrate 1, which is ideal with respect to its intrinsic material properties and / or the processed structures 2. The substrate 1 represents an idealized target state in which all structures 2 are perfectly manufactured and corrected. In general, a target state will only be a state to be achieved; that is, the structures 2 will not be manufactured in an idealized manner. Figure 2 shows a simplified top view of a distorted substrate T. The distortions are clearly recognizable in the structures 2', which are twisted, stretched, compressed, sheared, hidden, or otherwise deformed. The representation of the distorted substrate T is greatly exaggerated. Usually, the magnitude of the distortions is on the order of micrometers or even nanometers. However, distortions on the order of millimeters are conceivable.The distortions of the structures 2' can arise in a variety of ways. Possible causes include errors in exposure processes, coating processes, etching processes, multiple bonding and debonding processes necessary for the production of individual parts of the structures 2', cleaning processes, plastic deformation, self-expansion, etc. A further influencing factor can be temperature changes in conjunction with inhomogeneous and / or anisotropic thermal expansion of the substrate T and / or the structures 2', which leads in particular to plastic deformation. The distortions could also arise from elastic and / or plastic deformation. Regardless of the cause of the distortions of the structures 2', such substrates T are undesirable and very difficult to process further. Therefore, the aim is to develop a method and a device that can produce a substrate 1 according to Figure 1 from a substrate T from Figure 2.One could also say that the structures 2' of the current state are already distorted and are now to be corrected by targeted newly created distortions in order to transition to the desired state.

[0128] Figure 3 shows a simplified side view of a distorted substrate T, on the underside of which a layer system 3, comprising several layers 5, has been applied. The distorted substrate has structures 2'. In particular, the distortion can be seen in Figure 3 by the fact that the central structure 2' is located too far to the right. The layer system 3 can comprise any number of layers 5. In a layer 5, a chemical and / or physical reaction can be induced by an influencing agent, in particular electromagnetic radiation, most preferably by a laser. This chemical and / or physical reaction causes the part of the substrate 2' located above the area of ​​influence to distort accordingly and preferably to reach the desired target state. Figure 3 is also intended to show that, according to the invention, only a substrate T and a corresponding layer system 3 are necessary.

[0129] Figure 4 shows a simplified side view of a distorted substrate T with a layer system 3, which is preferably placed directly onto a substrate holder 6, in particular, fixed by means of fixing elements 7. The substrate holder is preferably transparent so that a control element (not shown) can act on the layer system 3 through the substrate holder 6. It would also be conceivable, though less preferred, to fix the substrate T to the substrate holder 6 via the substrate surface 10'. In this case, the transparency of the substrate holder 6 would be necessary to monitor the changes in the structures 2' on the substrate surface 10' while the control element acts on the layer system 3 from the top (not shown). In another conceivable device, the substrate holder 6 would be opaque.In this case, one would need to know the current state of the structures 2' and work exclusively with empirical data and / or models to correctly set the target state. A support substrate 4, as shown in Figure 5, is a useful addition, but as can be seen in Figure 4, not necessary.

[0130] Figure 5 shows a simplified side view of a distorted substrate T on a support substrate 4, with a layer system 3 located between them. This embodiment is particularly advantageous when the substrate T is already very thin. In this case, the support substrate 4 primarily serves for mechanical stabilization. A combination of Figures 4 and 5 is also conceivable; that is, the embodiment according to Figure 5 is used, in which the substrate T is located on a support substrate 4 via the layer system 3, and this support substrate 4 is then fixed to a substrate holder 6 according to Figure 4.

[0131] Figure 6 shows a side view of the manipulation of a preferred layer system 3 comprising a reaction layer 5r and a solvent layer 5I. The left image shows how a manipulation agent 8, preferably a laser, acts on the reaction layer 5r. The reaction layer 5r is connected to a substrate 1 on which several structures 2 are located, one of which, structure 2', is not in its desired target position. Preferably, the manipulation agent 8 can selectively reach and influence only the reaction layer 5r. The right image shows the result of the manipulation by the manipulation agent 8. In this embodiment, the manipulation agent 8 has led to a local volume expansion of the reaction layer 5r. This, in turn, leads to a local distortion 9 in the substrate 1 and causes structure 2' (left image) to be displaced to its target position.It's conceivable that in this case, the volume expansion occurred solely due to the heat input and recedes again when the system cools down. The volume expansion would therefore be reversible. @.

[0132] Nevertheless, substrate 1 could be in a desired state with all its structures 2 for a few seconds or even minutes.

[0133] Figure 7 shows a side view of the manipulation of a layer system 3 according to the invention, comprising two reaction layers 5r, 5r' and a solvent layer 5I. The left image shows how a manipulation agent 8, preferably a laser, acts on the reaction layer 5r'. Several structures 2 are again located on the substrate 1, one of which, structure 2', is not in its desired target position. Preferably, the manipulation agent 8 can selectively reach and influence only the reaction layer 5r'. The right image shows the result of the manipulation by the manipulation agent 8. In this embodiment, the manipulation agent 8 has locally caused blistering in the reaction layer 5r'. The material of the reaction layer 5r' is, for example, sublimated.The reaction layer 5r could be a plastically deformable layer whose shape is retained even when the sublimated gas from the layer system 3 diffuses. The gas bubble 10, in turn, leads to a local distortion 9 in the substrate 1 and ensures that the structure 2' (left image) is shifted to its desired position.

[0134] Figure 8 shows a side view of the manipulation of a layer system 3 according to the invention, comprising two reaction layers 5r, 5r' and a solvent layer 5I. The left image shows how a manipulation agent 8, preferably a laser, acts on the reaction layer 5r'. Several structures 2 are again located on the substrate 1, one of which, structure 2', is not in its desired target position. Preferably, the manipulation agent 8 can selectively reach and influence both reaction layers 5r, 5r'. The right image shows the result of the manipulation by the manipulation agent 8. In this embodiment, the manipulation agent 8 has locally caused a reaction between the reaction layers 5r and 5r', resulting in a new material composition 11, in particular an alloy.The material composition 11 may have a completely new crystal system and / or lattice system and exhibit entirely different and / or new chemical and / or physical properties compared to the materials of the reaction layers 5r, 5r'. The newly formed material composition 11, in turn, leads to a local distortion 9 in the substrate 1 and causes the structure 2' (left image) to be shifted to its target position.

[0135] Figure 9 shows a side view of the modification of a layer system 3, comprising two reaction layers 5r, 5r' and a dissolution layer 5I, and is to be understood as a further development of the embodiment in Figure 8. In this specific extension of the embodiment from Figure 8, the material 11 itself does not yet generate the distortion 9. However, the physical properties of the material composition 11 are utilized by a second modification agent 8' in such a way that the distortion 9 can be generated, and in particular, even controlled.For example, it would be conceivable that by selectively choosing the reaction layers 5r, 5r' and using the influencing agent 8, a specific material composition 11 with electrorestrictive properties could first be produced, and in a further process step according to Figure 9, an electrorestrictive control of the material 11, which causes the distortion 9, could be achieved using an externally applied electric field, which can now be considered a second influencing agent 8'. Materials 11 with magnetically controllable properties, i.e., magnetorestrictive materials, would also be conceivable.

[0136] Reference symbol list:

[0137] 1, 1' Substrate in general

[0138] 10 substrate surface

[0139] 1s large-area substrate, especially wafers

[0140] 1c chip, chiplet or platelet substrate

[0141] 2, 2' structure

[0142] 3-layer system

[0143] 4 Carrier substrate

[0144] 5r reaction layer

[0145] 5I Solvent layer

[0146] 6 substrate holders

[0147] 7 fixing elements

[0148] 8, 8' Influencing agent

[0149] 9 Distortion

[0150] 10 Gas bubble

[0151] 11 Material, in particular alloy

Claims

Claims 1. Method for transferring a structure (2', 2) arranged on and / or embedded in a substrate (1 , 1') from an actual state to a desired state, in particular before further processing, such as singulation or pickup by a substrate holder (6), and / or before and / or during bonding of substrates (1 , 1'), comprising: - Providing a substrate (1, T) with at least one structure (2', 2) in its current state, - Providing at least one reaction layer (5r), which is in particular integrated into a layer system (3), - Realizing an active connection between the at least one reaction layer (5r) and the substrate (1, T), wherein the active connection is designed such that a change state in the at least one reaction layer (5r) causes a deformation in the substrate (1 , 1'), - Triggering the change state in the at least one reaction layer (5r) by means of an influencing agent (8), wherein the change state in the at least one reaction layer (5r) is caused in a locally limited manner such that the structure (2', 2) is transformed from the actual state to the desired state.

2. Method according to claim 1, wherein to change in the at least one reaction layer (5r) a volume and / or a lattice structure in the at least one reaction layer (5r) is locally changed and / or a locally confined gas bubble (10) is generated in the at least one reaction layer (5r).

3. Method according to one of the preceding claims, wherein the layer system (3) is formed from the at least one reaction layer (5r) and at least one solvent layer (5I).

4. Method according to one of the preceding claims, wherein the layer system (3) comprises several, in particular different, reaction layers (5r). - 25 / 28 - 5. Method according to one of the preceding claims, wherein the change state is limited in time.

6. Method according to one of the preceding claims, wherein the reaction layer (5r) is formed continuously below the structure (2, 2') or below several structures (2, 2').

7. Method according to one of the preceding claims, wherein the substrate (1 , 1') and the at least one reaction layer (5r) are arranged on a support substrate (4) and / or a substrate holder (6).

8. Method according to one of the preceding claims, wherein light from a laser source and / or an electric and / or magnetic field and / or thermal energy is used as the influencing means (8).

9. Method according to claim 8, wherein the light is guided through an at least partially transparent, preferably fully transparent, substrate holder (6) and / or an at least partially transparent, preferably fully transparent, support substrate (4).

10. Method according to one of the preceding claims, wherein the influencing agent is applied to the reaction layer in a locally and preferably temporally modulated manner.

11. Method according to one of the preceding claims, wherein the influencing agent (8) changes the material composition in the at least one reaction layer (5r).

12. Method according to claim 11, wherein the change state in the at least one reaction layer (5r) is induced by means of a further influencing agent in the material composition.

13. Method according to one of the preceding claims, wherein the substrate (1, T) is bonded to a further substrate, wherein a transfer of the structural @ tur from the actual state to the target state is carried out during the bonding process.

14. Arrangement of substrate (1 , 1') with a structure (2, 2') in its current state and at least one reaction layer (5r), in particular integrated into a layer system (3), for carrying out a method according to one of the preceding claims.

15. Device for carrying out the method according to any one of the preceding claims 1 to 13, wherein the device comprises at least one influencing means (8).

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