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

The method corrects substrate distortions using a reaction layer altered by an influencing agent, addressing alignment challenges in heterogeneous integration and enhancing bond quality and throughput.

WO2026092821A1PCT designated stage Publication Date: 2026-05-07EV GRP E THALLNER GMBH
View PDF 3 Cites 0 Cited by

Patent Information

Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
EV GRP E THALLNER GMBH
Filing Date
2024-10-28
Publication Date
2026-05-07

AI Technical Summary

Technical Problem

Existing methods for aligning and bonding substrates face challenges due to manufacturing defects and distortions, which can lead to deviations in the micrometer or nanometer range, affecting bond quality and throughput, particularly in heterogeneous integration processes like wafer-to-wafer and chip-to-wafer bonding.

Method used

A method involving a reaction layer integrated into a layer system on or within the substrate, which is altered by an influencing agent to induce a localized change, allowing transformation from an actual to a desired state, correcting distortions and ensuring precise alignment and bonding.

Benefits of technology

Enables precise correction of distortions in the micro- and nanometer range, ensuring reliable bonding and improving throughput by transforming substrates into an ideal starting point for further processing, particularly in fusion bonding.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure EP2024080458_07052026_PF_FP_ABST
    Figure EP2024080458_07052026_PF_FP_ABST
Patent Text Reader

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.
Need to check novelty before this filing date? Find Prior Art

Description

[0001] ■□I

[0002] EV Group E. Thallner GmbH MSP Ref: 43590 PT-WO PM / SK

[0003] Method for transforming a structure from an actual state to a desired 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 bonded directly to each other.

[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] The claimed method of the present invention can also be used, in particular, to distort already isolated functional units, especially chips, chiplets, or dies, particularly before and / or during a bonding process onto a large substrate or another isolated functional unit. The term "substrate" is used synonymously in the following text for large-area substrates, especially wafers, and isolated functional units, especially chips, chiplets, or dies. In particular, it is intended to bond a substrate in the form of an isolated functional unit to a large-area substrate in the form of a wafer for a temporary or permanent connection.

[0017] The functional units preferably have a thickness of less than 1 mm, preferably less than 100 pm, more preferably less than 50 pm, most preferably less than 1 pm, and most preferably less than 100 nm. Handling such functional units becomes increasingly difficult, especially at thicknesses below 100 pm. The comparatively small thicknesses allow for a particularly effective transition from the current state to the desired state, as a functional connection can be established very easily. This also permits, for example, a particularly high spatial resolution during the transition from the current state to the desired state. This makes it particularly easy to ensure that structures are perfectly congruent during bonding, or that the outer circumference of the functional unit or structure follows a desired profile.

[0018] 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.

[0019] 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 of the reaction layer to the back surface and the total thickness of the substrate is such that it is between 0.2 and 0.87, preferably between 0.3 and 0.87, and particularly preferably between 0.5 and 0.87. In specific embodiments, the reaction layer is located less than 50 pm, more preferably less than 25 pm, most preferably less than 1 pm, most preferably less than 500 nm, and most preferably less than 100 nm from the structures to be influenced.

[0020] The subsequent layer system is therefore arranged close to the side of the structure without contacting it.

[0021] By means of an influencing agent, such as a laser and / or an electric field, the reaction layer is locally altered physically and / or chemically at desired locations in such a way that this alteration results in a correction that restores the desired state of the substrate. This achieves the creation of a desired target state. For the first time, this makes it possible to selectively and, in particular, permanently adjust deviations in the micro- and / or nanometer range between the actual state and the target state, thus providing an ideal starting point for further processing steps or treatment. In particular, the method yields substrates that represent an ideal starting point for a fusion bond.

[0022] In particular, it may also be desirable to set the target state of a structure in such a way that features of the structure, i.e. certain properties, such as a geometric @

[0023] The form must be congruent with 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 occur, the structure must assume a state that is meaningful for the subsequent process, which may depend on other features or properties that are not present on the substrate itself, but rather on another substrate or a tool.

[0024] 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.

[0025] 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 careful selection of the layer's position, particularly its thickness, allows for precise control of the deformation while simultaneously protecting the substrate and the structure.Advantageously, the reaction layer, particularly in the form of a solvent layer, can also be embedded in materials that possess sufficient elasticity and thus allow deformation (without brittle fracture) in the event of partial destruction of the reaction layer. In particular, it is intended that a gap exists between the layer system or the reaction layer and the @.

[0026] Structure smaller than 50 nm, preferably smaller than 25 pm, even more preferably smaller than 1 pm, most preferably smaller than 500 nm and most preferably smaller than 100 nm.

[0027] 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.

[0028] 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 assess and document 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, thus eliminating the need for any control mechanism.

[0029] In particular, a substrate is understood to be either a large-area substrate, especially a wafer, or a single, functional unit produced from a large-area substrate, i.e., a die, chip, chiplet, etc. Where a reaction layer is mentioned, it is to be understood as the at least one reaction layer.

[0030] 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 is 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.

[0031] 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.

[0032] 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.

[0033] In this context, a strict distinction between displacement and distortion will no longer be made unless explicitly stated. The goal is always to create a desired state from the current state. However, these terms are familiar to those skilled in the field of elasticity theory. The substrate to be corrected can also be understood as the product substrate, since functional units for a final product are preferably produced on it.

[0034] Preferably, the modification is achieved by locally changing the volume and / or lattice structure of 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.

[0035] 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 structuring the layer system through the selection and / or sequence of 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.

[0036] 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.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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.

[0041] Preferably, the layer system is formed from at least one reaction layer and preferably 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.

[0042] The solvent layer of the layer system preferably comprises at least one material from one of the following material classes:

[0043] • Dielectric, in particular o Nitrite, in particular

[0044] ■ TiN, CrN, TaN, AIN, NiN, Si3N4o Carbide, especially carbon layers o Carbonitride, especially

[0045] ■ SiCN oxide and / or polymer and / or

[0046] Electric, preferably @ or metal, in particular

[0047] ■ Cr, Al, Ta, Co, Ni, Mn, Fe, Au, Ga, Sn, Ge, W, Cu, In

[0048] 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.

[0049] 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:

[0050] • 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

[0051] ■ AI, Sn, In, Ga

[0052] • 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

[0053] 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.

[0054] 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.

[0055] 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.

[0056] Preferably, the influencing agent affects several or all reaction layers simultaneously at one position, i.e., in a locally limited area.

[0057] 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 have 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 an initiation, the half-life is long compared to the time until the next processing step, and / or the change state is maintained by repeated initiation at least until the next further processing step.

[0058] 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.

[0059] 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).

[0060] 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.

[0061] 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.

[0062] 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 used, 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.

[0063] 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 EM 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 support substrate is preferably transparent to the laser beams.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] In one embodiment, the influencing agent acts on the reaction layer in a spatially and preferably temporally modulated manner. This allows for different degrees of influence of the influencing agent on the reaction layer to be set, 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.For example, it is conceivable to simultaneously expose different areas of the reaction layer with multiple beam paths, each of which is preferably processed or manipulated differently to exert a targeted inhomogeneous effect on the reaction layer. This allows for effects of varying magnitudes to be induced in the reaction layer simultaneously. It is also conceivable that properties of the laser light, such as its degree of focus or spot size in the area of ​​the reaction layer, could be adjusted during a single pass or for different areas of the reaction layer.

[0068] The reaction layer can be modified. For example, one or more lenses are moved to control the extent of the laser light's effect on the reaction layer in a targeted manner, particularly with spatial resolution.

[0069] 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.

[0070] 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.

[0071] The laser parameters can be selected such that only partial disruption occurs in the layer system, particularly in the reaction layer and / or the solution layer. The resulting distortions nevertheless lead to deformation of the wafer.

[0072] 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.

[0073] 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, for example, with regard to the transparency of the substrate to a specific type of light that is absorbed by the reaction layer to induce the change.

[0074] 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.

[0075] 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.

[0076] 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 contraction or expansion due to its phase properties.

[0077] For example, it is provided that the substrate is at least partially bonded to a larger substrate, in particular via the structure. Preferably, it is provided that at least one chip is bonded to the substrate, wherein a transformation of the structure on the substrate and / or the chip from its current state to the desired state is carried out during the bonding process.

[0078] Particularly preferred, it is also conceivable that the reaction layer could be used for post-processing a bonding process, in particular a bonding process of a substrate designed as a functional unit to a substrate designed as a wafer, or when bonding a substrate used as a functional unit to a wafer.

[0079] The substrate is used. In particular, the method is used in a C2W (chip-to-wafer) bonding process. The additional substrate is preferably a larger substrate or support substrate. Specifically, the functional unit is more than ten times, preferably 25 times, and most preferably more than 50 times smaller than the additional substrate with respect to lateral extent, i.e., extent parallel to the main plane of extension. Post-processing can advantageously correct any unintended distortions that may have occurred during the bonding process. If correction can be made during the bonding process itself, a post-processing step is advantageously eliminated. In particular, it is provided that the structures in the substrate provided as the functional unit are aligned with the structures in the substrate provided as the wafer.The reaction layer can be formed on the substrate configured as a functional unit and / or on the substrate configured as a wafer. It is particularly preferred that the reaction layer on the substrates is formed on the side opposite the interface through which the structures contact each other. In particular, several individual substrates configured as functional units can also be bonded to a common substrate configured as a wafer.

[0080] The method is preferably applied before further processing of the substrate and / or bonding of a chip. However, for large-area substrates, especially wafers, a particularly preferred embodiment allows the method to be applied during the bonding of a substrate provided as a chip, i.e., as a functional unit with a structure. By applying the method during bonding, displacements or distortions caused by the bonding process itself, particularly by the propagation of the bond wave between the substrate and the chip, can be actively compensated by introduced distortions. It is also conceivable to apply the method before bonding to prepare the substrate and / or the chip for bonding. In particular, the method is applied to a substrate and a chip before the bonding process.The two target states resulting from the actual states are preferably identical after the application of the method to the substrate and the chip.

[0081] The process can not only be used to distort a structured substrate by applying a manipulation agent so that the structures are shifted into a desired position, but it can also serve to intentionally prestress the substrate before C2W (chip-to-wafer) or D2W (die-to-wafer) assembly. C2W and D2W are used synonymously in the following text.

[0082] It is also conceivable that a substrate designed as a functional unit is brought into a specific shape, particularly a convex shape with respect to the bonding surface, by the influencing agent before bonding, so that the chip first makes point contact with the substrate or a second chip during bonding. It is preferably intended that the reaction layer is formed on the side facing a intended bonding surface. It would be conceivable that the chip is flattened by applying pressure to the bonding tool after point contact. Alternatively, it would be conceivable that a bond wave propagates spontaneously between the chip and the substrate after point contact, thus drawing the chip onto the substrate. In this case, no additional pressure would be necessary.

[0083] In a D2W process, several small substrates, chips, chiplets, or dies are bonded to other small substrates or to a larger substrate, particularly a wafer, using a chip bonder. During the bonding process, the formation of a bond wave creates tension between the small and large substrates, causing the small substrate to deform or fail to bond completely. Therefore, it is conceivable that the substrate area to which the small substrate is to be bonded is straightened before bonding using an appropriate process. The D2W bond then takes place immediately. The straightening process may have resulted in plastic and / or elastic deformation. It is crucial that the bond between the small and large substrates is as complete and defect-free as possible.

[0084] Preferably, the substrate is dissolved in a process that initiates a change state, transforming the structure from its current state to the desired state. This allows for simultaneous separation during the transition to the desired state. The substrate and structure preferably form part of a sandwich structure, with the reaction layer positioned between the substrates, which are preferably interconnected via the reaction layer. This allows, for example, the creation of a relatively thin substrate with a structure, as it can be grown on the reaction layer to form the sandwich structure. In this case, for instance, two substrates provided as a functional unit can be connected. Preferably, the structure is embedded within the grown substrate.When the substrate is dissolved with the structure, a transition from the actual to the desired state can be achieved by influencing the reaction layer. The substrates provided as a sandwich structure are preferably functional units.

[0085] Simultaneously transitioning from the current state to the target state and detaching the substrate with the structure advantageously allows both the transfer (for which detachment is necessary) and the target state to be achieved in a single step within the transfer of the substrates provided as a functional unit. The substrate to be bonded, particularly as a functional unit, is then advantageously in the target state during the bonding process.

[0086] For this purpose, the layer system between the substrates preferably includes a solvent layer, or alternatively, the reaction layer is also designed as a solvent layer. A solvent layer can thus be used in a single, functional unit, for example, as follows: A layer system with at least one reaction layer and / or a solvent layer is produced on a large-area substrate, in particular a wafer. Preferably, the solvent layer and the reaction layer are identical, i.e., they are produced and / or provided by a common layer, in particular made of the same material. At least one further layer is produced on the layer system, preferably by epitaxy, which can serve as the starting point for the fabrication of a functional unit, in particular a chip, chiplet, or MEMS component.It is also conceivable that at least one additional layer is created by a bonding process to form the layer system. After the structures in the functional units are fabricated, the large-area substrate is isolated. The chips obtained in this way are bonded to another large-area substrate, a product substrate, and / or other existing chips. Subsequently, the influencing agent, in particular a laser, is applied to the reaction layer, which is preferably designed as a release layer. The epitaxially grown part of the substrate, formed as a chip, remains on the product substrate, and the remaining part can be removed. During the release process, a desired straightening is simultaneously achieved by targeted application of the influencing agent to the reaction layer. Thus, straightening and separation are performed simultaneously.

[0087] Another possible application of the solvent layer involves creating a layer system with at least one reaction layer and one solvent layer on a large-area substrate, particularly a wafer. Preferably, the solvent layer and the reaction layer are identical. At least one further layer is then created on the layer system, preferably by epitaxy, which can serve as the starting point for the fabrication of a functional unit, in particular a chip, chiplet, or MEMS component. It is also conceivable that the at least one further layer is created by a bonding process to the layer system. After the structures in the functional units have been fabricated, the large-area substrate is not separated, but only grooves are created that surround the functional units and preferably extend beyond the solvent layer.The large-area substrate remains intact as a whole and is bonded to another substrate. Up to this point, it is still a W2W bonding process. The application of a bonding agent then destroys the bonding layer, allowing the functional units of the pre-formed grooves to be separated from the large-area substrate. The large-area substrate thus simultaneously fulfills the function of a carrier substrate. In particular, this allows for a transition back to the original state at a point in time when the substrates, provided as functional units, are transferred to another substrate and detached from the substrate serving as the carrier substrate.

[0088] In another embodiment, the method is applied before the separation (dicing) of a substrate into smaller substrates. The substrate is distorted or rectified in such a way that an optimal target state is achieved, enabling the individual small substrates, the dies, to be separated from the larger substrate as ideally as possible.

[0089] In another embodiment, the method is used to compensate for an obviously discernible curvature of a small substrate before it is picked up by a C2W bonder, i.e., in particular before bonding. By introducing distortions, an existing curvature can be counteracted and the small substrate flattened. This process preferably takes place after re-thinning and before and / or after dicing. Preferably, the method is applied while the substrate to be separated, or the already separated individual small substrates, are still on a support substrate, preferably a dicing tape. In another embodiment, the small substrates, which are bonded to form the large-area substrate with the C2W bonder, are distorted before and / or during and / or after bonding using the method according to the invention.In this case, a corresponding layer system must also be present on the small substrates. However, this case is simply a special case of the embodiments mentioned above, which were generally disclosed for a substrate. By applying the method to small substrates, it is particularly possible to fully bond incompletely bonded small substrates, especially those whose corners are incompletely bonded, to the large-area substrate or to other small substrates. This embodiment is also suitable for performing an overlay correction. This refers to the fact that the small substrates bonded to the large-area substrate have undergone displacement, rotation, or distortion during the bonding process. The actual state of the structure on the larger-area substrate therefore does not have the desired relationship to the actual state of the structure on the smaller substrate.By applying an influencing agent to an existing layer system, a correction can be made in this regard, especially if no heat treatment has yet been carried out to convert the pre-bond into a permanent fusion bond.

[0090] 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.

[0091] 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.

[0092] The following describes a process as it is carried out in a semiconductor factory (fab).

[0093] In a first process step, data describing the current state of a substrate and / or a chip 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".

[0094] 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.

[0095] In a third process step, the necessary processing steps will be calculated and determined in order to achieve the desired current state.

[0096] In a fourth process step, the system as described here and the described method for transitioning the substrate and / or the chip from the 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 be as close as possible. The goal is to minimize deviations between the target state and the current state. 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 capabilities 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.

[0097] 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.

[0098] 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 with 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. In a seventh step, the substrate and / or chip, now in the desired state, is processed using a different method. For example, a bonding process could be performed with a second substrate that has also undergone this process, and / or with additional chips.

[0099] In an eighth process step, the result of the seventh process step is verified and evaluated. Since the substrate, now populated with chips, can be further processed, it is necessary to restart the process from the first to the third steps, depending on how much data is already available about the substrate stack or the substrate itself.

[0100] 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.

[0101] In a first embodiment, the plant system consists of only a single cluster.

[0102] • Cluster

[0103] • Surveying device

[0104] • Device for transferring the substrate and / or the chips from the current state to the target state

[0105] • Bonding device, in particular a C2W or D2W bonder, or another device for carrying out further process steps

[0106] • Debonding device

[0107] In this embodiment, all devices are grouped in the same location, in the same cluster.

[0108] 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.

[0109] • Cluster 1 o Surveying device

[0110] • Device for transferring the substrate and / or the chips from the current state to the target state • Cluster 2 o Bonding device, in particular a C2W or D2W bonder, or another device for carrying out further process steps

[0111] • Cluster 3 or Debond device

[0112] This embodiment has the same number of devices as the first embodiment, however, the devices are grouped into clusters and these are distributed geographically.

[0113] In a third embodiment, the plant system also consists of three clusters.

[0114] • Cluster 1 o Surveying device

[0115] • Device for transferring the substrate and / or the chips from the current state to the target state

[0116] • Cluster 2 o Bonding device, in particular a C2W or D2W bonder, or another device for carrying out further process steps

[0117] • Cluster 3 o Debond device o Surveying device

[0118] The third cluster also has a surveying device.

[0119] In a fourth embodiment, the plant system consists of four clusters.

[0120] • Cluster 1 o Device according to the invention

[0121] • Cluster 2 o Bonding device, in particular a C2W or D2W bonder, or another device for carrying out further process steps

[0122] • Cluster 3 o Surveying device

[0123] • Cluster 3 or Debond device

[0124] The functions of the aforementioned devices are as follows. @

[0125] The measuring device is designed to measure a substrate and / or chips before, during, and / or after any process step. Measurement is preferably performed optically, but can also be acoustic or by tactile measurement (AFM).

[0126] The device for transferring the substrate and / or the chips 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 and / or the chip from the actual state to the desired state by means of an influencing agent on a reaction layer.

[0127] A bonding device is a device for bonding chips to substrates and / or to other chips. This device is commonly referred to simply as a bonder.

[0128] A debonding device is understood to be a device with which it is possible to separate a substrate or a chip. 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.

[0129] Further advantages, features, and details of the invention will become apparent from the following description of preferred embodiments and from the drawings. These show:

[0130] Figure 1 shows a top view of an undistorted substrate in a desired target state,

[0131] Figure 2 shows a top view of a distorted substrate in an undesired state.

[0132] Figure 3 shows a side view of a substrate with a layer system according to an exemplary embodiment of the present invention.

[0133] 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.

[0134] 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.

[0135] Figure 6 shows a side view of a first embodiment,

[0136] Figure 7 shows a side view of a second embodiment,

[0137] Figure 8 shows a side view of a third embodiment,

[0138] Figure 9 shows a side view of a fourth embodiment,

[0139] Figure 10a shows a side view of a first process step,

[0140] Figure 10b shows a side view of a second process step,

[0141] Figure 10c shows a side view of a third process step and

[0142] Figure 10d shows a side view of a fourth process step,

[0143] Figure 11 shows a side view of a debonding process.

[0144] Figure 12 Side view of a large-area substrate on which a layer system was deposited over the entire surface

[0145] In the figures, identical components or components with the same function are marked with the same reference symbols.

[0146] 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 that is ideal with respect to its intrinsic material properties and / or the processed structures 2. The @.

[0147] Substrate 1 represents an idealized target state in which all structures 2 are perfectly manufactured and aligned. In general, a target state will only be a state to be strived for; that is, the structures 2 will not be manufactured in an idealized way.

[0148] Figure 2 shows a simplified top view of a distorted substrate T. The distortions are clearly visible in the structures 2', which are twisted, stretched, compressed, sheared, hidden, or otherwise deformed. The representation of the distorted substrate T is greatly exaggerated. The magnitude of the distortions is usually in the micrometer or even nanometer range. However, distortions in the millimeter range 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-elongation, etc.Another 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 deformations. These distortions could also arise from elastic and / or plastic deformation. Regardless of the cause of the distortions in 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' in their current state are already distorted and are now to be straightened by deliberately introduced distortions in order to transition to the desired state.

[0149] 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.

[0150] 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, and in particular, fixed in place 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 is 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.

[0151] 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.

[0152] Although Figures 3 to 5 show a layer system 3 on a large-area substrate 1, T, such a layer system 3 can also be applied to a smaller, isolated substrate, in particular a chip, chiplet or die. The term substrate is therefore interpreted as broadly as possible in the context of the invention and can also include isolated substrates, in particular a chip, a chiplet or a die.

[0153] 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.In this case, it is conceivable that the volume expansion occurred solely due to the heat input and recedes upon cooling of the system. The volume expansion would therefore be reversible. Nevertheless, the substrate 1, with all its structures 2, could remain in a desired state for several seconds or even minutes. If a subsequent bonding or placement process with a C2W bonder is performed promptly, a desired bonding result can be achieved even in this case. This case is intended to demonstrate that the invention does not necessarily relate only to permanent distortions. Of course, a permanent distortion is conceivable and preferred in this specific case, particularly one caused by permanent volume expansion, especially by plastic deformation of the material.

[0154] 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.

[0155] Figure 8 shows a side view of the influence on a layer system 3 according to the invention, comprising two reaction layers 5r, 5r' and a solvent layer 5I. The left image shows how an influencing agent 8, preferably a laser, acts on the reaction layer 5r'. Several structures 2 are again located on the substrate 1, of which structure 2' is again not in its desired target position.

[0156] Preferably, the influencing agent 8 can selectively reach and influence both reaction layers 5r and 5r'. The result of the influence by the influencing agent 8 is visible in the right-hand image. In this embodiment, the influencing 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 can have a completely new crystal system and / or lattice system and exhibit completely different and / or new chemical and / or physical properties than the materials of the reaction layers 5r and 5r'. The newly formed material composition 11, in turn, locally causes a distortion 9 in the substrate 1 and ensures that the structure 2' (left-hand image) is shifted to its desired position.

[0157] 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.

[0158] Figures 6 to 9 illustrate some possible physical effects that can be used to distort a large-area substrate 1. Analogous effects exist when the layer system 3 is applied to a single substrate, a chip, chiplet, or die; that is, the measures shown in Figures 3 to 9 are used analogously to bring about a change from an actual state to a desired state of the substrate, in particular the functional unit, by inducing a change state in the reaction layer.

[0159] Figure 10a shows a side view of a large-area substrate 1s, which has several structures 2. Each of these structures 2 is, for example, a functional unit, such as a microchip. In this case, the structures 2 on the substrate 1s are already in their desired state, meaning that applying the method to the substrate 1s is not necessary this time. Accordingly, for the sake of clarity, no layer system 3 has been drawn on the substrate 1s.

[0160] Figure 10b shows a side view of a substrate 1s to which several smaller substrates 1c, also featuring a structure 2, were aligned and bonded, particularly using a C2W bonder. The structures 2 can be, for example, functional units such as a memory chip. By connecting a structure 2 on substrate 1s and another structure 2 on substrate 1c, a chip with the functionality of both structures 2 is subsequently created through heterogeneous integration. For the sake of simplicity, the representation of TSVs, intermediate layers, or other features is omitted here. Furthermore, the substrates 1c are depicted as very thick and large to improve clarity. It is evident that one of the bonded substrates 1c' was not bonded across its entire surface.The bond wave could not propagate completely and, particularly at the corners of substrate 1c', did not make contact with the underlying substrate 1s. It is conceivable that a corresponding layer system 3 is located on the back side of substrate 1c.

[0161] Figure 10c shows a side view of a substrate 1s in which a manipulation device 8, in particular a laser, acts on the layer system 3 of the imperfectly bonded substrate 1c'. This causes a distortion of the substrate 1c' such that the substrate 1c' is perfectly bonded to the substrate 1s again at the corners. For the sake of completeness, it is mentioned that the layer system 3 could theoretically also be located between the substrates 1c, 1c' and the substrate 1s. In this case, the layer system 3 would simultaneously function as a bonding system. However, there would then also have to be contacts, in particular TSVs, which establish an electrically conductive connection between the structures 2 of the substrate 1s and the structures 2 of the substrates 1c. In this case, the manipulation device 8 would also have to act through the substrates 1c, 1c' and / or the substrate 1s and should not damage the layer system 3 too severely.This case is rather suboptimal and will therefore not be discussed further.

[0162] Figure 10d shows a side view of a substrate 1s in which all substrates 1c have now been fully and correctly bonded.

[0163] Figure 11 shows a side view of three process steps for an alternative use of a layer system 3. The layer system 3 is located between two @

[0164] Substrates 1c, which preferably together form a chip 1c. In particular, the structure 2 is embedded here in the substrate shown below, which is formed by epitaxial growth on the layer system 3, and in the illustrated embodiment preferably terminates flush with the substrate 1c shown below on the underside. The two substrates 1c shown, together with the layer system 3, form a sandwich structure. Such a structure can be produced, for example, by providing a large-area substrate (not shown) with the layer system 3, and by creating a layer, in particular an epitaxial layer, on the layer system 3, which then forms the substrate, in which the structure 2 is produced. Subsequently, the large-area substrate (not shown) would be singulated, yielding a component shown in the first process step in Figure 11 (on the left).By applying a manipulation device 8, in particular a laser, distortion and / or separation would be possible, provided that the layer system 3 consists of a reaction layer 5r and / or a solvent layer 5I (for the sake of clarity, the explicit representation of the reaction layer 5r and / or the solvent layer 5I in the layer system 3 is omitted). In this way, a particularly thin chip, as shown in the third process step of Figure 11, can be produced. If no solvent layer 5I exists in the layer system 3, distortion can at least be carried out using the reaction layer 5r, which is located very close to the structure 2. In particular, it is provided that the distance between the layer system 3 and the structure 2 is less than 10 pm, preferably less than 5 pm, and most preferably less than 2.5 pm.This makes it particularly easy to correct or change structure 2, since substrate 1c between layer system 3 and structure 2 is comparatively thin.

[0165] Figure 12 shows a side view of a large-area substrate 1s on which a layer system 3 has been deposited over its entire surface. At least one further layer was then produced on the layer system 3 by epitaxy and / or by a bonding process. This layer is intended to form the actual functional units 1c, the chips, chiplets, or dies with their corresponding structures 2. By means of separation agents, in particular optical means such as a laser, or mechanical tools, in particular cutting tools such as blade or wire saws, grooves 12 are produced that extend into the layer system 3, in particular to a release layer (not shown). The large-area substrate thus produced now has several prefabricated but not yet detached functional units 1c, which can still be distorted and / or detached via the layer system 3.Through a W2W process, the functional units 1c can be bonded via their free surfaces to a second large-area substrate, which may also already contain functional units. By using an influencing agent, the functional units 1c are then distorted accordingly by a reaction layer 5r and separated from the large-area substrate by a dissolution layer 5I.

[0166] List of reference symbols:

[0167] 1, 1' Substrate in general

[0168] 10 substrate surface

[0169] 1s large-area substrate, especially wafers

[0170] 1c chip, chiplet or platelet substrate

[0171] 2, 2' structure

[0172] 3-layer system

[0173] 4 Carrier substrate

[0174] 5r reaction layer

[0175] 5I Solvent layer

[0176] 6 substrate holders

[0177] 7 fixing elements

[0178] 8, 8' Influencing agent

[0179] 9 Distortion

[0180] 10 Gas bubble

[0181] 11 Material, in particular alloy

[0182] 12 Nut

Claims

Claims 1. Method for converting 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 or during further processing, such as singulation or pick-up by a substrate holder (6), and / or before and / or during and / or after bonding a substrate (1c) preferably designed as a functional unit to a substrate (1s, 1c) preferably designed as a wafer or as a functional unit, for example during dissolution, 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 preferably 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).

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), wherein in particular the light is guided through an at least partially transparent, preferably completely transparent, substrate holder (6) and / or an at least partially transparent, preferably completely transparent, support substrate (4).

9. 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), wherein in particular the change state in the at least one reaction layer (5r) is brought about by means of a further influencing agent in the material composition.

10. Method according to one of the preceding claims, wherein the reaction layer (5r) is used for post-processing a bonding process, in particular a bonding process of a substrate (1c) designed as a functional unit to a substrate (1s) designed as a wafer, or when bonding a substrate (1c) used as a functional unit to a substrate (1s) designed as a wafer. - 35 / 37 - is used.

11. Method according to one of the preceding claims, wherein, upon loosening the substrate, the change state is initiated by which the structure is transformed from the actual state to the desired state.

12. Method according to one of the preceding claims, wherein the reaction layer (5r) is also a solvent layer (5I).

13. Method according to one of the preceding claims, wherein the substrate (1 , 1') is bonded to a further substrate, wherein a transformation of the structure from the actual state to the desired 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).

Citation Information

Patent Citations

  • Process and substrate system for separating carrier substrates

    WO2023179868A1

  • Method and device for compensating distortion

    WO2023078528A1

  • Multi-layer release stack for light induced transfer of components

    WO2023167582A1