METHOD FOR THINNING SOLID LAYERS INSERTED WITH COMPONENTS, AND MULTI-COMPONENT ARRANGEMENT

Description

[0001] The present invention relates according to claim 1 to a method for separating at least one solid layer from at least one solid body or to a method for providing at least one solid layer and according to claim 15 to a multi-component arrangement (see DE 10 2014 014486 A1, which discloses the preamble of claims 1 and 15).

[0002] A number of components in the semiconductor industry require thinned solid-state layers or substrates. However, since thin substrates are difficult to handle in conventional processes, and even wafers can only be produced up to a specific thickness using conventional wire-sawing processes, the most common method for manufacturing such components on thin substrates is grinding away or back-thinning the substrate after processing is complete.

[0003] In this process, a conventional wafer is fully processed before the final desired substrate thickness is achieved by removing excess material in a grinding and polishing step. This situation is disadvantageous for two reasons: firstly, valuable material is lost in the grinding step; secondly, the grinding / polishing step has the potential to damage the substrate and lead to a total loss of the already processed components, which already contain a large part of the wafer's added value.

[0004] Another method for thinning solids is disclosed in WO2014 / 177721A1. According to this method, a polymer layer is applied to a solid. By tempering the polymer layer, stresses are then generated in the solid, which separates a solid layer from the remaining solid.

[0005] The document DE 10 2012 001 620 A1 describes the use of an additional sacrificial layer between the solid body and the polymer film. This layer serves to improve the removal of the polymer film after the cleavage step, for example by chemically decomposing or detaching the sacrificial layer through the addition of suitable reactants. A disadvantage of this process, however, is the long time, which can be up to several hours, that elapses until the polymer layer is completely removed. This severely limits industrial use. To accelerate the polymer removal process, it is possible to introduce additional driving forces in the form of suitable tensile stresses that are effective even at room temperature through appropriate pretreatment. These lead to an increase in the attack surface for the reactants or the solvent and promote decomposition or detachment and dissolution.

[0006] Furthermore, WO 2010 / 072675 A2 discloses the inclusion of fillers in the polymer to locally influence the thermal expansion coefficient or the elastic modulus. However, it has been found that such fillers often impair the adhesion of the polymer to the surface of the solid to be divided, thus preventing sufficient force transmission.

[0007] DE 10 2013 016 682 A1 relates to a method for producing solid-state layers, the method comprising the following steps: providing a solid-state body for separating at least one solid-state layer; generating defects by means of a radiation source, in particular a laser, in the internal structure of the solid-state body to define a crack initiation point from which the solid-state layer is separated from the solid-state body and / or generating defects by means of the radiation source in the internal structure of the solid-state body to define a crack path along which the solid-state layer is separated from the solid-state body; arranging a receiving layer for holding the solid-state layer to the solid-state body;thermally applying the receiving layer to generate stresses in the solid body, whereby the stresses cause a crack to propagate from the crack initiation point and / or along the crack path in the solid body, whereby the crack separates the solid body layer from the solid body;

[0008] US 2009 / 0242010 A1 describes a method for separating a semiconductor layer from a wafer. The method comprises creating a separation plane in the wafer, attaching the wafer to a support element, and separating the semiconductor layer from the wafer along the separation plane. Creating the separation plane includes implanting ions into the wafer.

[0009] DE 10 2015 006 971 A1 describes a method for separating a semiconductor layer from a first wafer. The method comprises attaching the first wafer to a second wafer, creating modifications in the first wafer using laser beams, thereby defining a crack plane, and applying mechanical stress to the first wafer to separate the semiconductor layer from the first wafer along the crack plane. The modifications in the first wafer can be created before or after attaching the first wafer to the second wafer.

[0010] It is therefore an object of the present invention to improve the thinning of semiconductor substrates, in particular by preserving material and reducing wafer losses (the so-called yield loss) and / or to provide a possibility for more advantageous production of electrical components and / or to provide advantageous multi-component arrangements.

[0011] The aforementioned object is achieved according to claim 1 by a method for providing at least one solid layer, wherein the solid layer is separated from a solid. The method according to the invention preferably comprises at least the following steps: generating a plurality of modifications by means of laser beams inside the solid to form a detachment plane, wherein the modifications generate compressive stresses in the solid, separating the solid layer by separating the remaining solid and the solid layer along the detachment plane formed by the modifications, wherein at least components of the modifications generating the compressive stresses remain on the solid layer, wherein as many modifications are generated,that the solid layer detaches from the solid due to the modifications or wherein an external force is introduced into the solid to generate further stresses in the solid, wherein the external force is so strong that the stresses cause crack propagation along the detachment plane formed by the modifications, generating a material layer, in particular a metal layer, on the surface exposed by the separation of the solid layer from the solid to at least partially and preferably mostly and particularly preferably completely compensate for a deformation of the solid layer caused by the compressive stresses of the remaining modification components or to at least partially and preferably mostly or completely compensate for the compressive stresses.

[0012] This solution is advantageous because it allows for very flat solid layers to be created without the need for machining the solid layer. This is particularly useful for the solid material SiC, as its production is very expensive and material losses must therefore be avoided wherever possible. Furthermore, SiC is very hard, requiring the use of very expensive grinding tools, which wear out very quickly due to SiC's high hardness. This solution is also useful because the solid layers provided are already coated with a material layer, particularly a metal layer, to form an electrical contact and / or an interface for heat dissipation.

[0013] According to a preferred embodiment of the present invention, the surface of the solid-state layer exposed as a result of the separation has first surface portions that have an Ra value (average roughness) of less than 1, in particular less than 0.9 or less than 0.7 or less than 0.5, in particular between 0.01 and 0.4. Furthermore, the exposed surface of the solid-state layer preferably has second surface portions that have an Ra value (average roughness) of more than 1, in particular between 1 and 5. The proportion of the first surface portions is preferably greater than the proportion of the second surface portions, wherein the second surface portions constitute at least 1% or at least 2% or at least 5% or at least 10% or between 1% and 49% or between 1% and 40% or between 1% and 30% or between 1% and 20% of the total area formed from the first surface portions and the second surface portions.This solution is advantageous because the solid layer, even with portions having Ra values ​​between 1 and 5, can be further processed, particularly without further surface conditioning, such as grinding or lapping.

[0014] According to a further preferred embodiment of the present invention, the material layer, in particular the metal layer, is produced on the solid-state layer in a first aggregate state and a temperature above room temperature and is present in a second aggregate state at room temperature, wherein, through the transition from the first aggregate state to the second aggregate state, the metal layer acts on the solid-state layer to at least partially compensate and preferably completely compensate the deformation or compressive stresses caused by the compressive stresses of the remaining modification components.Alternatively, the metal layer can be produced on the solid-state layer in a temperature range above room temperature, wherein the temperature range is at least 100°C or 150°C or 200°C or 250°C or 300°C or 350°C or 400°C above room temperature and particularly preferably up to a maximum of 2000°C or lower than the melting or evaporation temperature of the solid-state material, wherein the cooling of the metal layer to room temperature acts on the solid-state layer to at least partially compensate and preferably completely compensate for the deformation caused by the compressive stresses of the remaining modification constituents or to compensate for the compressive stresses. Thus, the cooling and / or solidification of the metal layer creates forces, in particular tensile forces, by which the solid-state layer is deformed preferably negatively to the deformation caused by the compressive stresses or by which the compressive stresses are compensated.The compressive stresses preferably cause a deformation referred to as a bow. Room temperature is preferably defined as 20°C, although room temperature can also describe the temperature in a process chamber, which can preferably be between 0°C and 100°C or between 20°C and 200°C.

[0015] According to a further preferred embodiment of the present invention, the metal layer is produced by sputtering or electrochemical deposition. For example, in the case of a SiC solid-state layer containing modification components, known sputtering materials or materials suitable for electrochemical deposition, such as titanium, titanium tungsten, nickel, platinum, TaSi2, and / or gold, are preferably used. The thickness of the metal layer is preferably determined by the parameters of the thickness of the solid-state layer, the material of the solid-state layer, the area of ​​the solid-state layer, and the number and type of modifications.

[0016] According to a further preferred embodiment of the present invention, the solid body consists of silicon carbide (SiC) or comprises silicon carbide (SiC), wherein the solid body layer is preferably separated from the solid body with a thickness of less than 200 µm, in particular with a thickness of less than 150 µm, or less than 125 µm, or less than 110 µm, or less than 100 µm, or less than 90 µm, or less than 75 µm. This solution is advantageous because SiC is very easy to control using the methods proposed here, and thus electrical components can be produced with significantly less material loss and with significantly less wear on the treatment equipment.

[0017] According to a further preferred embodiment of the present invention, the electrical components are vertical components, in particular Schottky diodes and / or metal oxide semiconductor field-effect transistors (MOSFETs), wherein the metal layer forms an electrical contact, in particular an ohmic contact, and / or forms an interface for heat dissipation. This embodiment is advantageous because, with the present invention, vertical components can be produced very flat (e.g., through the use of SiC) and thus also lighter, with comparatively low material and wear losses. This creates the possibility of producing significantly more energy-efficient and cost-effective electrical components.

[0018] According to another preferred embodiment of the present invention, the electrical components are horizontal components, in particular high-electron-mobility transistors (HEMTs), with the metal layer preferably forming an interface for heat dissipation. This embodiment is advantageous because these components can be manufactured smaller, lighter, and more cost-effectively.

[0019] According to a further preferred embodiment of the present invention, a plurality of electrical components, in particular at least 4 or at least 9 or at least 36 or at least 100, are produced on average per cm² of a planar surface side of the solid-state layer, wherein the electrical components are separated from one another by dicing after their production. This embodiment is advantageous because the individual electrical components can be separated from one another quickly and very gently. The individual electrical components preferably have rectangular, in particular square, base areas. The electrical components preferably have outer edges between 0.1 mm and 5 mm.

[0020] Preferably, a laser modification layer is created in the solid or substrate, particularly before processing the components. This layer defines the subsequent thin layer or detachment layer. Particularly preferably, the further processes for building up or creating layers and / or for component production (lithography, etc.) take place only afterward.

[0021] The layers and / or components which form the composite structure together with the solid-state layer are preferably produced by means of lithography, in particular coating with, for example, metal compounds, resist coating, optical exposure (e.g. scanning through a photomask), developing the photoresist (in particular at low temperatures, such as temperatures below 70°C, in particular below 50°C or below 30°C or below ambient temperature or below 20°C or below 5°C or below 0°C), etching of structures. To produce a circuit, in particular a finished circuit, individual or several or all of these processes, in particular lithography processes, can be repeated multiple times, in particular more than 10 times or up to 10 times or more than 20 times or up to 20 times or more than 40 times or up to 40 times or more than 80 times or up to 80 times.

[0022] The solid remaining after the separation of the solid layer preferably has a thickness that is greater, in particular several times greater, than the thickness of the separated solid layer. The solid material is preferably a semiconductor material or comprises a semiconductor material.

[0023] It should be understood that "on or above" a surface of the solid layer to be separated can also be understood to mean that, in the case of a high-temperature step preceding the laser treatment to create the modifications, a coating can be applied to the surface created by the high-temperature process, on which the additional layer(s) and / or components for creating the composite structure are then arranged or created. By definition, the composite structure is only created after the laser treatment; any multilayer arrangement present prior to the laser treatment is referred to as a multilayer arrangement in this patent application, not as a composite structure.

[0024] Thinning here means reducing the thickness of the solid body, which is preferably a wafer, by the amount of material that would be removed abrasively, e.g. milled, ground or polished, in conventional manufacturing processes for solid bodies provided with components, in particular wafers.

[0025] Further preferred embodiments are the subject of the subclaims and the description parts listed below.

[0026] According to a preferred embodiment of the present invention, for introducing the external force, a receiving layer is arranged on an exposed surface of the composite structure, wherein the receiving layer comprises a polymer material and the receiving layer is subjected to thermal stress to generate, in particular mechanical, stresses in the solid body. The thermal stress represents a cooling of the receiving layer to a temperature below the ambient temperature. The cooling takes place in such a way that the polymer material of the receiving layer undergoes a partial or complete crystallization and / or a glass transition, and the stresses cause a crack in the solid body to propagate along the detachment plane, which crack separates the first solid layer from the solid body, or the external force is introduced into the solid body by applying ultrasound to the solid body.The solid body is preferably arranged in a container filled with a liquid. Ultrasound can be used with a frequency range of 20 kHz to 100 kHz, but also in the high-frequency sound range with a frequency range of 100 kHz to 1 MHz. Due to these frequencies, cavitation processes occur primarily on solid bodies in liquid media, with consequences such as collapsing cavitation bubbles. In liquid media, particularly in the area of ​​phase boundaries, implosion and deformation of dynamically forming cavitation bubbles and the formation of a microjet occur in the nanosecond range. The spatially resolved energy release occurs in the form of adiabatic heating in a very small space due to the very rapid compression of the gas. Extreme temperatures of up to 5000 Kelvin and pressures of up to 500 bar occur.which enable new physical reactions in the boundary layer region that would otherwise not occur. These enormous pressure differences result from the outward recoil of the bubble front (imploding shock wave). This results in greatly increased reaction rates in this region. According to the invention, a spatially resolved CNC-controlled application using an ultrasonic tip (sonotrode) is particularly preferred, which can specifically influence crack initiation and / or crack propagation. The spatially resolved pressure application can be used specifically for crack initiation and / or crack propagation.

[0027] The homogeneous and / or spatially resolved embodiment is advantageous because, particularly when using the recording layer, a very precise force introduction and thus crack initiation and / or crack guidance can be achieved.

[0028] According to a further preferred embodiment of the present invention, the solid body is treated with at least one high-temperature process prior to the production of the detachment plane, wherein the high-temperature process is carried out at a temperature between 70°C and the melting temperature or evaporation temperature of the material of the solid body.

[0029] Thus, performing the laser step on a partially processed wafer represents another possibility. According to the invention, this is particularly preferably done after the high-temperature steps but before the remaining processes. This solution is advantageous because not all structures that could be damaged by the laser process have yet been formed.

[0030] In this case, parameters of the laser process can be optimized in such a way that the stress in the solid body is minimized as much as possible, e.g. by gently applying the laser to the solid body multiple times, by increasing line spacing and decreasing energies with each pass.

[0031] The laser process is preferably carried out depending on the crystallographic orientation of the substrate. This means that the laser modification is particularly preferably carried out in such a way that microcracks arising during the treatment neither hinder lithography nor protrude supercritically from the modification plane and lead to substrate loss after the separation crack is initiated. For example, in SiC, initial lines can be directed parallel to the preferred crack direction to define a crack plane. In a second step, lines 90° to this direction are applied to finally initiate the cracks and define the separation plane.

[0032] Performing the high-temperature steps before creating the detachment plane is highly advantageous, since a significant increase in temperature above 70 °C is associated with increased mobility of dopant atoms, atoms of metallic impurities, dislocations, or other crystal defects. If the detachment plane had been created or partially created before the high-temperature step, microcracks resulting from this could extend or grow further into the solid or into the solid layer to be separated, requiring more material to be removed and thus resulting in greater losses.

[0033] According to a further preferred embodiment of the present invention, the at least one high-temperature process is an epitaxial process, a doping process, or a process using plasma. High-temperature processes are understood to mean all processes, in particular material-depositing processes, that are carried out at a temperature above 70°C. The temperature occurring is preferably less than 2000°C or less than the melting or evaporation temperature of the solid material. The high-temperature process preferably creates a multilayer arrangement of solid material and the one or at least one produced or arranged layer.

[0034] According to a further preferred embodiment of the present invention, at least one layer is produced on the solid body by the high-temperature process, wherein the at least one produced layer has predefined parameters, wherein at least one predefined parameter specifies a maximum degree of refraction and / or absorption and / or reflection and / or charge carrier generation by photoelectric effect of laser light waves, wherein the degree of refraction and / or absorption and / or reflection and / or charge carrier generation by photoelectric effect is less than 5% and preferably less than 1% and particularly preferably less than 0.1%. This embodiment is advantageous because interactions between all metallic elements of the circuit and laser light are prevented. As a result of interactions between a metallic layer or metallic components and laser light or laser radiation, the metallic layer and / or the components, in particular electrical conductor connections, can be damaged.

[0035] Furthermore, this embodiment solves the further problem that when the laser plane is introduced, if metallic structures or components (e.g. greater than 20 nm in length or extension in the laser penetration direction) are already arranged or produced on the substrate, the laser process is disrupted either by back reflections from the structures or by the structures themselves, because, for example, the transmission is not ideal. Since a multiphoton process is preferably used to produce the material modifications, the focus in the material must preferably be very precise, in particular ideal, in order to enable the required high intensities while at the same time ensuring the wavefronts are as undisturbed as possible. This advantage therefore also speaks in favor of laser treatment before the processing or production of the final structures, in particular layers and / or components.

[0036] According to a further preferred embodiment of the present invention, the modifications are preferably generated by means of multi-photon excitation, in particular two-photon excitation.

[0037] Preferably, a plurality of basic modifications are first generated on a line that runs at least in sections homogeneously, in particular curved, in particular in the homogeneously running section. These basic modifications are preferably generated with or depending on predefined process parameters. The predefined process parameters preferably include at least the pulse duration, pulse energy, pulse spacing within a line, distance between the lines, depth and / or numerical aperture. Preferably, at least one value of these process parameters and preferably several values ​​or all values ​​of these process parameters or more than two values ​​of these process parameters are determined depending on the crystal lattice stability of the solid. The value s 0 is particularly preferably selected such that the crystal lattice around the respective basic modifications remains intact, i.e.preferably less than 20µm or less than 10µm or less than 5µm or less than 1µm.

[0038] According to a further preferred embodiment of the present invention, trigger modifications for triggering subcritical cracks are generated, wherein at least one process parameter for generating the trigger modifications is different from at least one process parameter for generating the basic modifications, preferably several process parameters are different from one another. Additionally or alternatively, the trigger modifications can be generated in a direction that is inclined or spaced from the direction of the line along which the basic modifications are generated, wherein the subcritical cracks preferably spread by less than 5 mm, in particular less than 4 mm or less than 3 mm or less than 2 mm or less than 1 mm or less than 0.5 mm. An inclined orientation can, for example, correspond to an angle between 0° and 90°, preferably an angle between 85° and 90° and particularly preferably an angle of 90°.

[0039] It is a threshold process that is triggered when a critical intensity (i.e., power / area) is exceeded. This means that short pulses require less energy per pulse, while a higher numerical aperture concentrates the energy onto a smaller spot, thus requiring less energy to reach the threshold intensity.

[0040] A greater depth usually means absorption losses, which is why the energy must be adjusted accordingly, example SiC: NA=0.4, 180µm depth, 3ns pulse length, pulse energy approx. 7µJ, at 350µm depth more like 9µJ.

[0041] In general, harder materials (sapphire, aluminum oxide ceramic, SiC, GaN) require larger pulse overlap in the lines, i.e. smaller pulse spacings (<=1µm), for which the line spacings tend to be chosen larger (e.g. >5µm), while softer materials such as GaAs and Si tend to require larger pulse spacings (>1µm) and therefore smaller line spacings (<5µm).

[0042] Example SiC pattern - with fs pulses: Pulse energy approx. 800 nJ, pulse spacing 50 nm and greater, up to 200 nm, line pattern as follows: 30 lines with 1 µm spacing, then a 20 µm gap, then another 30 lines, then a 96 µm gap, and then again from the beginning, crossed with 30 lines, a 20 µm gap, and 30 lines (always with a 1 µm spacing between the lines), then a 300 µm gap, and then another 30 / 20 / 30 line block. Depth 180 µm, doping level of the SiC (characterized by sheet resistance >21 mOhm cm), pulse length 400 fs, numerical aperture 0.65.

[0043] According to a preferred embodiment, the solid-state material is silicon, wherein the numerical aperture is between 0.5 and 0.8, in particular 0.65, the irradiation depth is between 150µm and 1500µm, in particular 300µm, the pulse spacing is between 1µm and 5µm, in particular 2µm, the line spacing is between 1µm and 5µm, in particular 2µm, the pulse duration is between 50ns and 400ns, in particular 300ns, and the pulse energy is between 3µJ and 30µJ, in particular 10µJ.

[0044] According to a preferred embodiment, the solid-state material is SiC, wherein the numerical aperture is between 0.4 and 0.8, in particular 0.4, the irradiation depth is between 50µm and 500µm, in particular 180µm, the pulse spacing is between 0.1µm and 3µm, in particular 1µm, the line spacing is between 10µm and 100µm, in particular 75µm, the pulse duration is between 100fs and 10ns, in particular 3ns, and the pulse energy is between 0.5µJ and 30µJ, in particular 7µJ.

[0045] Example sample aluminum oxide ceramic: pulse spacing 500nm, line spacing 10µm, pulse duration 3ns, pulse energy 22µJ, NA=0.4 Example sample sapphire: 3x written lines at 0°, 45°, 90°, each with 1.5µm line spacing, pulse spacing 300nm, pulse energy in the first pass 350nJ, in the second pass 300nJ and in the third pass 250nJ, with an NA of 0.65 and a pulse duration of 250fs.

[0046] In general, surface roughness decreases with shorter pulses. Femtosecond pulses can produce better surfaces (roughness below 3 µm) than nanosecond pulses (more likely above 3 µm), but the process is more expensive and takes longer. Picosecond pulses represent a middle ground. The advantage of shorter pulses is that the phase transition occurs athermally, i.e., coupling occurs between the laser pulse and the crystal lattice, so fewer vibrations (phonons) are excited—thus resulting in a cooler overall process. For this, larger areas must be amorphized (phase transition) to build up the critical stress that triggers the cracks.

[0047] According to a further preferred embodiment of the present invention, the subcritical cracks propagate in the solid body between 5 µm and 200 µm, in particular between 10 µm and 100 µm or between 10 µm and 50 µm or between 10 µm and 30 µm or between 20 µm and 100 µm or between 20 µm and 50 µm or between 20 µm and 30 µm. This embodiment is advantageous because smaller crack propagation requires less post-processing effort. The subcritical cracks propagate along the crystal lattice boundaries; however, since the crystal lattice of the solid body is preferably inclined relative to the detachment plane, in particular at an angle between 0° and 6°, the result is a sawtooth-shaped surface in profile.The further the cracks run, the greater the distance between the valleys and peaks of this sawtooth-shaped surface, which means that more material must be removed if a surface roughness of less than 80nm or less than 50nm or between 20nm and 50nm is to be achieved.

[0048] According to a further embodiment of the present invention, the crack propagation of the subcritical cracks thus proceeds in an inclined direction deviating from an angle of 90° relative to the direction of incidence of the laser beams; in particular, the crack propagation direction is preferably inclined between 93° and 95°, in particular exactly 94°, relative to the direction of incidence.

[0049] According to a further preferred embodiment of the present invention, the sections between the regions of several lines in which the subcritical cracks have propagated tear as a result of the stresses or the introduction of the external force, which are generated, for example, by the glass transition or the ultrasonic treatment. This embodiment is advantageous because, due to the pre-damage caused inside the solid, particularly due to the subcritical cracks, the required stresses can be significantly lower. Furthermore, the crack is guided very precisely.

[0050] According to a further preferred embodiment of the present invention, the receiving layer is arranged or produced on a surface of the solid body which is opposite the surface of the solid body on which the layers and / or components for forming the composite structure are arranged.

[0051] Before the crack is triggered, the receiving layer according to the method, in particular in the form of a polymer film, is applied to the side of the solid body on which preferably no further layer and / or components are arranged.

[0052] The receiving layer according to a further preferred embodiment of the present invention consists at least predominantly and preferably completely of the polymer material, wherein the glass transition of the polymer material is between -130°C and 0°C, in particular between -85°C and -10°C or between -80°C and -20°C or between -65°C and -40°C or between -60°C and -50°C.

[0053] According to a further preferred embodiment of the present invention, the polymer material of the receiving layer consists of a polymer hybrid material or comprises such a material which forms a polymer matrix, wherein a filler is present in the polymer matrix, wherein the polymer matrix is ​​preferably a polydimethylsiloxane matrix and wherein the mass fraction of the polymer matrix in the polymer hybrid material is preferably 80% to 99% and particularly preferably 90% to 99%.

[0054] According to the invention, a polymer hybrid material is therefore specified for use in a splitting process, in which at least two solid fragments are produced from a solid starting material. The polymer hybrid material according to the invention comprises a polymer matrix and at least one first filler embedded therein. References to one or the filler are also intended to encompass the possibility of multiple fillers. For example, the filler can comprise a mixture of different materials, e.g., metal oxides, metal particles, and inorganic fibers.

[0055] Any polymer or a mixture of different polymers capable of generating the stresses necessary for splitting the solid starting material can be used as the polymer matrix. For example, the polymer matrix can be designed as an elastomer matrix, preferably as a polydiorganolsiloxane matrix, particularly preferably as a polydimethylsiloxane matrix. Such polymer materials are particularly easy to use as matrix material in combination with fillers, since the properties can be flexibly adjusted and adapted to the respective filler and the solid starting material to be split due to the variable degree of crosslinking. According to one embodiment, the mass fraction of the polymer matrix in the polymer hybrid material is 80% to 99%, preferably 90% to 99%.

[0056] The first filler can be organic or inorganic in nature and can consist of a chemical element as well as a chemical compound or a mixture of substances, for example an alloy.

[0057] The first filler is designed to act as a reactant, initiator, catalyst, or promoter during the detachment of the polymer hybrid material from the solid-state portion after separation, thereby resulting in a faster detachment of the polymer hybrid material from the solid-state portion after separation compared to a polymer material without a first filler.

[0058] The specific chemical composition and design of the first filler, as well as its mass fraction, depend particularly on the specific material of the polymer matrix to be removed, the solvent used for this purpose, and the reactants employed. Furthermore, the material of the solid starting material and the dimensions of the solid starting material to be separated also play a role.

[0059] The specific proportion of the first filler in the polymer matrix depends heavily on the filler material and its mode of action. Firstly, the polymer matrix must still be able to fulfill its function of generating stresses despite the filler. Secondly, the proportion of the first filler must be high enough to achieve the desired effect on polymer removal. The expert can determine the optimal mass fraction of the first filler in each case using simple concentration-dependent tests.

[0060] An additional filler, such as fumed silica, can also contribute to improving mechanical properties by forming an inorganic network within the polymer. In addition to these strong interactions in the form of a network, less strong interactions through purely hydrodynamic reinforcements can also contribute to improvements. One example is a targeted increase in viscosity, which enables improved processing in the splitting process and can thus contribute to improved manufacturing tolerances. Furthermore, this interaction makes it more difficult for the internal degrees of freedom to undergo structural reorientation with increasing reinforcement.

[0061] This leads to a desired reduction in the glass transition temperature of the polymer used in the polymer hybrid material, which enables the advantage of a lower temperature in the splitting process. According to the invention, the first filler in a polymer hybrid material is used to accelerate the detachment of the polymer hybrid material from a solid-state piece obtained by splitting using a splitting process in which a solid-state starting material is divided into at least two solid-state pieces.

[0062] The first filler can be distributed in the polymer matrix such that the mass fraction of the first filler decreases, starting from the outer, i.e. lower, interface of the polymer hybrid material, which is connected to the solid starting material during the splitting process, in the direction of a further interface of the polymer hybrid material arranged parallel to the lower interface. This means that the mass fraction of the filler close to the solid starting material or section is greater than in the remaining regions of the polymer hybrid material. This distribution of the first filler enables particularly effective removal of the polymer hybrid material after separation, since the first filler is located close to the interface with the solid section and can exert its effect there.At the same time, the remaining areas of the polymer hybrid material contain less or no portion of the first filler, so that the function of the polymer is influenced as little as possible.

[0063] In one embodiment, the polymer hybrid material is constructed in layers, wherein only one layer facing the solid starting material comprises the first filler, while the remaining polymer hybrid material is free of the first filler.

[0064] Furthermore, a lower region of the polymer hybrid material, directly adjacent to its lower interface, can be free of the first filler. This can result in a region sequence as follows: Adjacent to the solid starting material, there is initially a region without the first filler, followed by a region with a high proportion of the first filler, and then a region with a low proportion of the first filler or without the first filler.

[0065] These and all regions described below can be formed in the form of layers, ie the region extends predominantly parallel to the interface of the solid starting material to which the polymer hybrid material is applied and has a longitudinal and transverse extension at least in the region of this interface.

[0066] A lower region without a first filler can be provided, in particular, in the event that the first filler impairs the adhesion of the polymer hybrid material to the solid starting material. To avoid this, a region without a first filler is initially arranged, followed by a region with a high proportion of first filler so that the first filler can fulfill its function. A lower layer without a first filler can, for example, have a thickness between 10 µm and 500 µm, for example 100 µm.

[0067] Furthermore, an upper region of the polymer hybrid material, which directly borders its upper interface, can be free of the first filler. The upper interface is understood to be the interface that separates the polymer hybrid material from the environment, opposite the lower interface and the solid starting material. The lower and upper interfaces can be arranged parallel to each other.

[0068] Such an upper region without a first filler can be provided in particular if the first filler adversely affects the heat transfer between the environment and the polymer hybrid material, for example if the cooling of the polymer hybrid material would be delayed.

[0069] The first filler may comprise or consist of a material that can react with a reactant, preferably an oxidizing agent, to release a gaseous product.

[0070] This allows cavities to be generated in the polymer matrix, which allow faster access of the reactants and solvents to the polymer matrix and any existing sacrificial layer and also result in faster removal of the reactants and dissolved components.

[0071] By generating gaseous reaction products, additional driving forces can be introduced that further support the removal of the polymer hybrid material.

[0072] The formation of additional cavities and the creation of gaseous reaction products accelerate polymer removal and thus contribute to an increase in the overall yield of the splitting process. By varying the proportion of the first filler, the cavity density in the interface between the solid section and the polymer hybrid material, or between the sacrificial layer and the polymer hybrid material, can be specifically influenced.

[0073] The first filler may comprise a metal, in particular aluminum, iron, zinc and / or copper, or may consist of a metal, in particular the aforementioned metals.

[0074] "Consisting of" includes, with respect to all materials mentioned here, the possibility of technologically induced impurities or technologically induced admixtures which, for example, are useful for the production of the fillers and their distribution or binding to the polymer matrix.

[0075] Metallic fillers can react with oxidizing agents such as hydrochloric acid, nitric acid, citric acid, formic acid or sulfamic acid to release a gaseous product and thus be removed from the polymer hybrid material.

[0076] For example, aluminum reacts with concentrated hydrochloric acid to form solvated metal ions and hydrogen according to the following equation: 6 HCl + 2 Al + 12 H 2 O → 2 [AlCl 3 *6 H 2 O] + 3 H 2

[0077] Similarly, the reaction of zinc as a filler with concentrated hydrochloric acid leads to the formation of 5 additional cavities: Zn + 2 HCl → ZnCl 2 + H 2 In the examples mentioned, the generation of hydrogen introduces additional driving forces that further assist the removal of the polymer hybrid material. In addition, the first filler can improve the thermal conductivity within the polymer hybrid material, for example, if the first filler has a higher thermal conductivity than the polymer of the polymer matrix. This can be the case, for example, if A further advantage in the case where the first filler comprises a metal lies in the improved thermal conductivity within the polymer hybrid material. As a result, the improved thermal conductivity allows the stresses generated for the division of the solid starting material by means of cooling to be more effective, i.e.faster and with lower coolant consumption. This can increase the overall yield of the splitting process.

[0078] Furthermore, a second filler can be provided in the polymer hybrid material, which increases the adhesion of the polymer hybrid material to the solid starting material compared to a polymer hybrid material without a second filler. Preferably, the adhesion is increased compared to a polymer material without a filler.

[0079] For example, the second filler can be a filler that can be activated by plasma. Plasma activation results in new surface species that can be created to result in stronger interaction with the surface of the solid starting material, thereby improving the adhesion of the polymer hybrid material.

[0080] The type of surface species that can be achieved through plasma treatment depends primarily on the plasma process. For example, gases such as nitrogen, oxygen, silanes, or chlorosilanes can be added during plasma treatment, creating polar groups that can interact more strongly with the surface of the solid starting material.

[0081] The second filler can be distributed in the polymer matrix such that the mass fraction of the second filler increases toward the lower interface. For example, the polymer hybrid material can contain the second filler only in a region adjacent to the lower interface, whereby the region can also be formed as a layer within the meaning of the above definition.

[0082] This allows the second filler to be arranged preferentially near the interface between the polymer hybrid material and the solid starting material, thereby improving adhesion and thus enabling greater force transfer into the solid starting material to be divided. For example, the second filler can comprise core-shell polymer particles.

[0083] Particles are preferred whose polymer composition differs from the polymer matrix of the polymer hybrid material in that, in particular, the surface, i.e., the shell, of the core-shell particles can be activated more strongly, e.g., by means of low-temperature plasma.

[0084] Examples of these are core-shell particles comprising a polysiloxane core with an acrylate shell, or comprising a nanoscale silicate core with an epoxy shell, or comprising a rubber particle core with an epoxy shell, or comprising a nitrile rubber particle core with an epoxy shell. The second filler can be activated by low-temperature plasma, e.g., cold plasma. For example, the plasma can be generated by dielectric barrier discharge (DBE). Electron densities in the range of 1014 to 1016 m-3 can be generated. The average temperature of the "cold" non-equilibrium plasma (plasma volume) generated by DBE is approximately 300 ± 40 K at ambient pressure. The average temperature of the non-thermal plasma generated by DBE is approximately 70 °C at ambient pressure.

[0085] In DBE treatment, for example, the surface is exposed to unipolar or bipolar pulses with pulse durations ranging from a few microseconds to several tens of nanoseconds and amplitudes in the single-digit to double-digit kilovolt range. There are no metallic electrodes in the discharge space, and therefore no metallic contamination or electrode wear is to be expected.

[0086] Another advantage is high efficiency, since no charge carriers have to enter or exit the electrodes.

[0087] Dielectric surfaces can be modified and chemically activated at low temperatures. Surface modification can occur, for example, through interaction and reaction of the surface species by ion bombardment.

[0088] Furthermore, targeted process gases such as nitrogen, oxygen, hydrogen, silanes or chlorosilanes, e.g. Si x H y E z with E=F,Cl,Br,I,O,H and x=0 to 10, z=0 to 10, SiH 4 , Si(EtO) 4 or Me 3 SiOSiMe 3 , can be added during a plasma treatment in order, for example, to generate certain chemical groups on the surface. The second filler can also be activated by corona 5 treatment, flame treatment, fluorination, ozonation or UV treatment or excimer irradiation. Such activation generates, for example, polar groups on the surface of the second filler, which can interact with the surface of the solid starting material and thus improve adhesion. The polymer hybrid material may further comprise a third filler in addition to a polymer hybrid material having a first filler or to a polymer hybrid material having a first and a second filler.This third filler has a higher thermal conductivity and / or a higher elastic modulus compared to the polymer of the polymer matrix.

[0089] For example, the polymer's elastic modulus at low temperatures is in the low single-digit gigapascal range (approx. 1-3 GPa), whereas metallic fillers, for example, exhibit an elastic modulus in the double-digit to triple-digit gigapascal range. With a sufficiently high filler content, a percolating filler network is possible, enabling improved force coupling into the solid-state starting material.

[0090] Percolation is significantly influenced by the volumetric filler content of the respective fillers (e.g., 0.1 vol%, 1 30 vol% to 10 vol% depending on the aspect ratio). With increasing force application, the viscoelastic layer structure of the polymer structure can be submerged, creating multiple percolation pathways. This can enable improved heat transfer, as it can lead to improved contact between the fillers and the surface of the solid starting material.

[0091] The mechanical stability of the polymer hybrid material is achieved more quickly, even at low temperatures. Overall, this results in a lower standard deviation of the corresponding structural property profiles, such as the stress at break and the strain at break of the polymer hybrid material, thus increasing the overall yield of the splitting process. The spatially resolved property profile changes (stress peaks in the polymer hybrid material) and thus in the solid are smaller, leading to a higher overall yield of the splitting process and better quality of the produced solid fragments.

[0092] The third filler can improve heat transfer between the environment and the polymer hybrid material and accelerate heat conduction within the polymer hybrid material, allowing the polymer hybrid material to be cooled more quickly and the splitting process to be carried out more quickly and effectively.

[0093] By increasing the elastic modulus, higher stresses can be generated for the division of the solid starting material, so that even solid starting materials can be divided for which a particularly high stress is required.

[0094] In addition, the third filler can also serve to influence the thermal expansion coefficient. The goal is to achieve the greatest possible difference between the thermal expansion coefficients of the polymer hybrid material and the solid starting material to be divided, in order to generate additional stresses necessary for the division. Preferably, the third filler has a high thermal expansion coefficient, i.e., a coefficient of expansion that is higher than that of the polymer matrix. For example, the thermal expansion coefficient of the third filler can be more than 300 ppm / K.

[0095] The third filler can be distributed in the polymer matrix in such a way that the mass fraction of the third filler increases towards the upper interface in order to enable faster heat transfer, particularly at the interface to the environment.

[0096] The third filler may comprise a metal, particularly aluminum, iron, zinc, and / or copper, or consist of one of the aforementioned metals. Metals are generally characterized by high thermal conductivity and thermal diffusivity.

[0097] The described fillers (first, second, third filler) can be present in particulate form distributed throughout the polymer matrix, with the particle size being in the µm and nm range, based on at least one dimension of the particle. In addition to a spherical shape, the filler particles can also take on other configurations, for example, a rod-like or disc-like shape.

[0098] The filler particles can have any particle size distribution, for example, monomodal or bimodal, narrow, especially monodisperse, or broad. The fillers can be bonded to the polymer matrix both physically, e.g., by embedding in the polymer network, or chemically. Furthermore, one or more of the described fillers can comprise or consist of inorganic or organic fibers, for example, carbon, glass, basalt, or aramid fibers, provided the previously described functions are compatible. Optionally, a further filler can also be added that comprises or consists of the aforementioned fibers.

[0099] Fibers typically exhibit highly anisotropic properties. By directional positioning of the filler in the polymer hybrid material, it is possible to specifically influence the stresses required for splitting the solid starting material. This can contribute to increasing the overall yield of the splitting process. An additional advantage is that using an organic or inorganic filler as a fiber with a highly anisotropic structure can improve the mechanical properties within the polymer hybrid material.

[0100] The described fillers may also comprise or consist of core-shell particles. Additionally or alternatively, a further filler comprising or consisting of core-shell particles may be provided in the polymer hybrid material.

[0101] The use of core-shell polymer particles not only allows for improved activation but also allows for a new design of energy-absorbing mechanisms, which can collectively lead to increased impact and fracture toughness, particularly low-temperature impact toughness, of the polymer hybrid material when used in the splitting process, thus also contributing to a higher overall yield of the splitting process. For example, mechanical destruction of a film made of a polymer hybrid material can occur with a lower probability, thus increasing the possibility of reusing the film.

[0102] For example, by preventing crack propagation due to core-shell polymer particles, destruction of the film during the splitting process can be prevented and thus recycling routes can be opened up.

[0103] The elastomer particles contained in the particles can undergo plastic deformation and form cavities, which can absorb additional energy. Additional energy absorption can also be compensated for by shear flow in the matrix, which improves the overall mechanical properties. Core-shell particles are characterized by the fact that a generally spherical core made of one material is surrounded by a shell made of a second material. The shell can either completely enclose the core or be permeable. The materials can be inorganic, such as metals, or organic, such as polymers. For example, two different metals can be combined. However, it is also possible to surround a polymer core with a shell made of a metal or a second polymer.

[0104] Core-shell particles allow the properties of the first and second materials to be combined. For example, an inexpensive polymer core can be used to control the size and density of the filler particles, while the metallic shell can react as described above. Due to their often monodisperse particle size distribution, the properties of the core-shell particles can also be precisely predicted and tuned.

[0105] In addition, one or more fillers (first, second, and / or third filler) may comprise or consist of carbon in the form of carbon black, graphite, chopped carbon fibers, carbon nanofibers, preferably in the form of carbon nanotubes (CNTs), such as multi-walled carbon nanotubes (MWCNTs) and single-walled carbon nanotubes (SWCNTs). Carbon nanotubes are cylindrical graphite layers composed of a varying number of cylinders.

[0106] If these tubes consist of only one cylinder, they are called single-walled carbon nanotubes (SWCNTs). If two or more cylinders are present, they are either double-walled (DWCNTs) or multi-walled carbon nanotubes (MWCNTs). These can preferably be nested concentrically.

[0107] Depending on various design variants, the third filler can comprise or consist of MWCNTs, as these possess particularly high thermal conductivity (> 3000 W*(m*K) -1< ) ​​and simultaneously exhibit very high tensile strength in the range of 5-60 GPa. The high mechanical stability is reflected in the high tensile strength, extreme elasticity, and very good durability of the filler.

[0108] This is based on the sp2 hybridized strong σ-CC bonds combined with a delocalized p orbital as a π bond to three neighboring carbon atoms. Bends of up to 90° are possible.

[0109] Even higher property values ​​can be achieved with SWCNTs (Young's modulus: 410 GPa to 4150 GPa vs. graphite: 1000 GPa, SWCNTs: thermal conductivity approx. 6000 W*(m*K) -1< ). However, this results in a poorer performance-to-cost ratio compared to MWCNTs. The cylinder diameters of MWCNTs typically range from 1 nm to 100 nm, preferably from 5 to 50 nm, with a length of 500 nm to 1000 µm.

[0110] According to further embodiments, the third filler can comprise MWCNT, and the second and / or first filler can simultaneously comprise or consist of carbon black, since this can also improve thermal conductivity (e.g., up to 200 W*(m*K) -1< ). Since the use of carbon black, for example, has a significantly lower tensile strength with values ​​of < 0.4 GPa, a combination of both or additional fillers is possible and can lead to an improvement in the overall splitting yield and an improvement in the overall costs of the splitting process.

[0111] 20 The average diameters of the carbon black particles are in the range from 5 nm to 500 nm, preferably from 20 nm to 200 nm, particularly preferably from 40 nm to 100 nm.

[0112] Furthermore, the fillers may comprise or consist of silica, for example, fumed silica. 25 Additionally or alternatively, a further filler comprising or consisting of silica may be provided in the polymer hybrid material.

[0113] Pyrogenic silica can form a three-dimensional network and thereby contribute to improving mechanical stability. Thus, such a filler can be used to specifically adjust the mechanical properties of the polymer hybrid material. One or more of the fillers mentioned (first, second, third filler) can consist of the same material, provided this is compatible with their assigned function. For example, both the first and third fillers can comprise or be made of aluminum. As described above, aluminum can be used both to generate cavities and thus accelerate the detachment of the polymer hybrid material from the solid part, and to increase thermal conductivity. Such a design simplifies the manufacturing process, since it may be sufficient to add only one or two fillers to fulfill all functions.

[0114] The first and second, and possibly the third, fillers can also be made of different materials. This allows for individual and thus better adaptation of the filler to the desired function.

[0115] A film according to the invention comprises a polymer hybrid material as described above. The film can have a thickness of, for example, 0.5 to 5 mm.

[0116] A polymer hybrid material or a film according to the invention is applied to at least this surface, resulting in a corresponding composite structure. The applied polymer hybrid material or film is also referred to below as the receiving layer. The thickness of such a receiving layer can be, for example, between 0.5 mm and 5 mm, in particular between 1 mm and 3 mm. Optionally, the polymer hybrid material or film can also be applied to several exposed surfaces, in particular to surfaces arranged parallel to one another.

[0117] The thermal exposure preferably represents a cooling of the receiving layer below the ambient temperature and preferably below 10 °C and particularly preferably below 0 °C and further preferably below -10 °C or below -40 °C.

[0118] The cooling of the receiving layer most preferably occurs such that at least a portion of the receiving layer undergoes a glass transition or undergoes partial or complete crystallization. The cooling can be achieved below -130°C, which can be achieved, for example, using liquid nitrogen. This embodiment is advantageous because the receiving layer contracts and / or undergoes a glass transition as a function of the temperature change, and the resulting forces are transferred to the solid starting material, thereby generating mechanical stresses in the solid that lead to the initiation of a crack and / or crack propagation. The crack initially propagates along the first detachment plane to separate the solid layer.

[0119] In a further step, the polymer hybrid material or film is removed from the solid part, for example by a chemical reaction, a physical detachment process and / or mechanical removal.

[0120] The detachment process of the polymer hybrid material from the solid-state portion can take place at moderate ambient temperatures, e.g., in the range of 20 °C to 30 °C, preferably in the higher temperature range of 30 °C to 95 °C, e.g., from 50 °C to 90 °C, or, for example, in a lower temperature range between 1 °C and 19 °C.

[0121] The increased temperature range can shorten a chemical stripping reaction due to an increase in the reaction rate, e.g., when using a sacrificial layer between the polymer hybrid material and the solid. When using a sacrificial layer, stripping can occur in an aqueous solution, advantageously at a pH value in the range of 2-6. According to various embodiments, the stripping process can, for example, take place in the form of a treatment with a solution of a suitable apolar solvent, with moderate ambient temperatures in the range of 1°C to 50°C being preferred, and 20°C to 40°C being particularly preferred.

[0122] A particular advantage of this method is the removal without any thermal impact on the film. Aliphatic and aromatic hydrocarbons such as toluene, n-pentane, n-hexane, as well as halogenated solvents such as carbon tetrachloride, can be used advantageously. This allows additional forces to be introduced into the polymer hybrid material being removed and the interface with the solid section, since solvent treatment can induce very strong, reversible swelling of the polymer hybrid material, which simplifies the removal process overall.

[0123] According to further embodiments, a combination of the above-described removal mechanism of the sacrificial layer and the treatment with a suitable apolar solvent can be carried out - also without temperature influence on the film.

[0124] A stabilization layer can be arranged or created on the exposed layer or the exposed components of the produced composite structure to limit deformations of the exposed layer or the exposed components, wherein the deformations result from the mechanical stresses introduced by the receiving layer. The side with components is thus preferentially protected and held (e.g. against warping of the substrate or the solid and gray space conditions). This can be achieved using soluble polymers (organic) or holding layers. This embodiment is advantageous because it limits interactions with, for example, small meme structures. The surface texture of a wafer with components is usually irregular, which can lead to field enhancements and local surface damage in the event of excessive or abrupt movements.Thus, this embodiment represents a solution that provides good protection of the solid-state layer and the layers and / or components arranged and / or produced thereon, in particular against mechanical damage or destruction.

[0125] The method may preferably also or alternatively comprise one or more of the steps: providing a solid body for separating at least one solid body layer, wherein the solid body has a first planar surface portion and a second planar surface portion, wherein the first planar surface portion is preferably aligned substantially or exactly parallel to the second planar surface portion.

[0126] Creating defects by means of at least one radiation source, in particular a laser, in the internal structure of the solid body to specify a crack initiation point from which the solid body layer is separated from the solid body.

[0127] Creating defects or modifications by means of laser beams from at least one laser in the internal structure of the solid body to predetermine a crack path along which the solid body layer is separated from the solid body, wherein the laser beams penetrate into the solid body via the second planar surface portion. According to a further preferred embodiment of the present invention, the stabilizing layer consists of or comprises a preferably water-soluble ceramic, in particular Fortafix from Detakta, and / or a soluble polymer, in particular poly(ethylene glycol) (PEG), in particular with different and / or adapted chain lengths. Fortafix are one- and two-component ceramic cements for use as adhesives, glazes for protection against corrosion and chemical influences, casting compounds for mold making or for insulation, as dipping compounds for attaching heating wires, for inserting knife blades, e.g. in metal or ceramic handles.The polymer (PEG) is soluble in water and a number of organic solvents. It is insoluble in hexane, diethyl ether, and tert-butyl methyl ether—other organic solvents. Accordingly, the surface structures / components can be filled with PEG before a protective layer is applied. The stabilizing layer is preferably created in-situ or provided as a film. Additionally or alternatively, the stabilizing layer is cast in, or the layer and / or the exposed components are exposed to a liquid material, which only becomes a stabilizing layer upon curing or solidification. The stabilizing layer is additionally or alternatively removed from the layer or the exposed components by applying a solvent or by immersion in a solvent. The stabilizing layer thus comprises or consists of a ceramic material and / or it comprises or consists of a polymer material.

[0128] According to a further preferred embodiment of the present invention, the modifications are produced successively in at least one row or row or line, wherein the modifications produced in a row or row or line are preferably produced at a distance X and with a height H, so that a crack propagating between two successive modifications, in particular a crack propagating in the crystal lattice direction, the crack propagation direction of which is oriented at an angle W to the detachment plane, connects the two modifications to one another. The angle W is preferably between 0° and 6°, in particular 4°. The crack preferably propagates from a region below the center of a first modification to a region above the center of a second modification.The essential connection here is that the size of the modification can or must be changed depending on the distance between the modifications and the angle W.

[0129] According to a further preferred embodiment of the present invention, in a first step the modifications are produced on a line and preferably at the same distance from one another. Furthermore, it is conceivable that a plurality of these lines produced in the first step are produced. These first lines are particularly preferably produced parallel to the crack propagation direction and preferably in a straight line or in the shape of a circular arc, in particular in the same plane. After the production of these first lines, second lines are preferably produced for initiating and / or driving preferably subcritical cracks. These second lines are also preferably produced in a straight line. The second lines are particularly preferably inclined with respect to the first lines, in particular oriented orthogonally.The second lines preferably extend in the same plane as the first lines, or more preferably in a plane parallel to the plane in which the first lines extend. Subsequently, third lines are preferably generated to connect the subcritical cracks.

[0130] According to a further preferred embodiment of the present invention, a cooling device is provided for cooling the receiving layer to a temperature between -130°C and -10°C, in particular to a temperature between -80°C and -50°C. The cooling device preferably has a nebulizing means, in particular at least or exactly one perforated pipe, for nebulizing liquid nitrogen, and the cooling effect is particularly preferably generated by nebulized nitrogen. Alternatively, it is conceivable for the cooling device to have a nitrogen bath, wherein the receiving layer is positioned at a distance from liquid nitrogen held in the nitrogen bath. Alternatively, it is conceivable for the cooling device to be provided with a spray means, in particular liquid or mist-like, which preferably provides nitrogen uniformly, wherein the spray means is preferably arranged above and / or to the side of the receiving layer.This embodiment is advantageous because liquid nitrogen is highly suitable for the controlled cooling of objects. Furthermore, this embodiment is advantageous because it provides a much more energy-efficient process compared to low-temperature processes below -80°C or below -90°C.

[0131] The cooling device preferably comprises a nitrogen bath and a positioning device for defined adjustment of the distance of the position of the receiving layer to the liquid nitrogen held in the nitrogen bath, wherein the nitrogen bath and the positioning device are preferably arranged in a space that is at least partially and preferably completely separated from the environment.

[0132] According to a further preferred embodiment of the present invention, one or more temperature measuring devices are provided. Temperature measurements are preferably performed with the temperature measuring device(s), with the detected temperature values ​​preferably being used to regulate the position or flow through a nitrogen valve for temperature control.

[0133] For more homogeneous temperature control, a fan can also be used inside the chamber, which creates forced convection and thus reduces temperature gradients.

[0134] Another cooling option (not shown) is contact cooling with a temperature-controlled heat sink, through which, for example, a coolant flows in a closed circuit and is brought into contact with the solid body.

[0135] The temperature measurement is preferably carried out on the solid body, in particular on the receiving layer and / or on the underside of the solid body, the underside of the solid body preferably being arranged at a distance from the chamber bottom, wherein a positioning device is preferably provided for positioning the solid body, by means of which the distance of the solid body to the chamber bottom or the distance of the receiving layer to the liquid nitrogen can be changed, in particular depending on the temperature.

[0136] Furthermore, a chamber for accommodating the nitrogen and the positioning device is preferably provided, wherein the chamber is preferably closable and / or thermally insulated from the environment.

[0137] According to the present description, a solid starting material is preferably understood to be a monocrystalline, polycrystalline, or amorphous material. Due to the strongly anisotropic atomic bonding forces, monocrystalline materials with a strongly anisotropic structure are particularly suitable. The solid starting material preferably comprises a material or a material combination from one of main groups 3, 4, 5, and / or transition group 12 of the Periodic Table of the Elements, in particular a combination of elements from main groups 3, 4, or 5 and transition group 12, such as zinc oxide or cadmium telluride.

[0138] In addition to silicon carbide, the semiconductor starting material can also consist of silicon, gallium arsenide GaAs, gallium nitride GaN, silicon carbide SiC, indium phosphide InP, zinc oxide ZnO, aluminum nitride AlN, germanium, gallium(III) oxide Ga2O3, aluminum oxide Al2O3 (sapphire), gallium phosphide GaP, indium arsenide InAs, indium nitride InN, aluminum arsenide AlAs or diamond.

[0139] The solid body or workpiece (e.g., wafer) preferably comprises a material or a material combination from one of the main groups 3, 4, and 5 of the Periodic Table of Elements, such as SiC, Si, SiGe, Ge, GaAs, InP, GaN, Al 2 O 3 (sapphire), or AlN. Particularly preferably, the solid body comprises a combination of elements from the fourth, third, and fifth groups of the Periodic Table. Conceivable materials or material combinations are, for example, gallium arsenide, silicon, silicon carbide, etc. Furthermore, the solid body can comprise a ceramic (e.g. Al 2 O 3 - aluminum oxide) or consist of a ceramic, preferred ceramics are, for example, perovskite ceramics (such as Pb-, O-, Ti / Zr-containing ceramics) in general and lead-magnesium niobates, barium titanate, lithium titanate, yttrium-aluminum-garnet, in particular yttrium-aluminum-garnet crystals for solid-state laser applications, SAW ceramics (surface acoustic wave), such asLithium niobate, gallium orthophosphate, quartz, calcium titanate, etc. in particular. The solid body thus preferably comprises a semiconductor material or a ceramic material, or more preferably the solid body consists of at least one semiconductor material or a ceramic material. The solid body is preferably an ingot or a wafer. More preferably the solid body is a material that is at least partially transparent to laser beams. It is thus also conceivable for the solid body to comprise a transparent material or to consist of or be partially made of a transparent material, such as sapphire. Other materials that can be considered as solid body material alone or in combination with another material are, for example, "wide band gap" materials, InAlSb, high-temperature superconductors, in particular rare earth cuprates (e.g. YBa 2 Cu 3 O 7 ).Additionally or alternatively, it is conceivable for the solid to be a photomask, whereby in the present case, any photomask material known at the filing date, and particularly preferably combinations thereof, can be used as the photomask material. Furthermore, the solid may additionally or alternatively comprise or consist of silicon carbide (SiC).

[0140] The modifications can represent a phase transformation of silicon carbide into silicon and carbon.

[0141] The laser exposure according to the invention preferably brings about a substance-specific, spatially resolved accumulation of the energy input, resulting in a defined tempering of the solid at a defined location or locations and within a defined time. In a specific application, the solid can consist of silicon carbide, whereby a highly locally limited tempering of the solid to a temperature of, for example, more than 2830 + / - 40°C is preferably carried out. This tempering results in new substances or phases, in particular crystalline and / or amorphous phases, wherein the resulting phases are preferably Si (silicon) and DLC (diamond-like carbon) phases, which arise with significantly reduced strength. This reduced-strength layer then creates the detachment region or detachment plane.

[0142] Furthermore, the aforementioned object is achieved by a solid body produced by a method mentioned above and having at least one detachment plane within the solid body, wherein the detachment plane is formed from modifications produced by laser radiation. Furthermore, the solid body has a region resulting from a high-temperature treatment process.

[0143] According to a further preferred embodiment, the layers and / or component(s) are arranged or produced in the region. Alternatively, the layers and / or component(s) can be arranged or produced on a surface of the solid layer to be separated. The solid preferably has a thickness or average thickness of less than 1000 µm, in particular less than 800 µm or 700 µm or 600 µm or 500 µm or 400 µm or 300 µm or 200 µm or 100 µm or 80 µm or 50 µm.

[0144] The subject matter of the invention is therefore also the production of components on such a pretreated / modified wafer and the modified wafer itself as the component substrate.

[0145] Furthermore, the present invention relates to a multi-component assembly according to claim 15. The multi-component assembly according to the invention is preferably produced by means of claim 1 or claim 2 and particularly preferably has at least one solid layer.The solid-state layer preferably consists of more than 50% (by mass), in particular more than 75% (by mass) or more than 90% (by mass) or more than 95% (by mass) or more than 98% (by mass) or more than 99% (by mass) of SiC, wherein the solid-state layer has modifications or modification components that generate compressive stresses in the region of a first surface, wherein the modifications are amorphized (phase-transformed) components of the solid-state layer, wherein the modifications are spaced closer to the first surface or form it than to a second surface, wherein the second surface is parallel or substantially parallel to the first surface, wherein the first surface is flat or substantially flat and / or wherein the second surface is flat or substantially flat.Furthermore, the multi-component arrangement according to the invention also has a metal layer produced on the first surface of the solid-state layer. Furthermore, it is possible for one or more further layers and / or one or more further components to be arranged on the second surface, in particular for forming electrical components that can be used as horizontal or vertical components.

[0146] Preferably, the modifications are spaced from the second surface by less than 200 µm, in particular less than 150 µm or less than 110 µm or less than 100 µm or less than 75 µm or less than 50 µm.

[0147] For the purposes of the present invention, a surface is preferably considered to be substantially flat if each square centimeter of the surface, when the surface is in contact with an ideally smooth and ideally flat surface, touches the ideally smooth and ideally flat surface with at least one component.

[0148] A surface is preferably considered to be flat in the sense of the present invention if each square centimeter, in particular square millimeter, of the surface, when the surface lies against an ideally smooth and ideally flat surface, touches the ideally smooth and ideally flat surface with at least several, in particular with at least 2, 3, 4 or 5 components.

[0149] Furthermore, the subject matter of patent application DE 10 2016 123 679.9 filed with the German Patent and Trademark Office on December 7, 2016, is incorporated in its entirety by reference into the present patent application.

[0150] Further advantages, objects, and features of the present invention will be explained with reference to the following description of the accompanying drawings, which illustrate the separation method according to the invention by way of example. Components or elements that are preferably used in the method according to the invention and / or that are at least substantially identical in terms of their function in the figures may be identified by the same reference numerals, although these components or elements need not be numbered or explained in all figures.

[0151] It shows: Fig. 1a - a treatment process according to the invention; Fig. 2a-b two schematic examples of solid-state arrangements as can be provided according to the invention; Fig. 3a-i further schematic examples of solid-state arrangements according to the invention or solid-state arrangements that can be produced in the process according to the invention - as an intermediate product; Fig. 4 a schematic representation of two lines formed by modifications; Fig. 5a-d various cooling devices that can preferably be used for cooling in the process according to the invention, Fig. 6a-c three different schematic examples of crack propagation between modifications, Fig. 7 differently oriented modification lines for effecting different functions, Fig. 8 an example of a Schottky diode and Fig. 9 an example of a MOSFET.

[0152] Fig. 1a shows the provision of the solid body 1, in particular a wafer.

[0153] According to Fig. 1b the provided solid body 1 is coupled or glued or welded or screwed or clamped to a tool carrier (chuck) 3, wherein the tool carrier preferably comprises a cooling functionality and thereby preferably becomes the cooling device 3. The solid body 1 is preferably fixed, in particular glued, to the cooling device 3 in the longitudinal direction with its underside, which preferably lies longitudinally opposite the surface 5. The laser beams are thus introduced into the solid body 1 in the direction of the cooling device 3 via the surface 5, which is a component of the solid body layer to be separated. Particularly preferably, a high-temperature treatment of the surface 5 is also carried out, in particular an epitaxial material arrangement on the solid body surface 5, which preferably results in a further layer 145 or several further layers 145.The at least one high-temperature process is preferably an epitaxial process, a doping process, or a process using plasma, wherein the high-temperature process, in particular in the case of an epitaxial process, produces at least one layer 145 on the solid body 1, wherein the at least one produced layer 145 has predefined parameters, wherein at least one predefined parameter specifies a maximum degree of refraction and / or absorption and / or reflection of laser light waves, wherein the degree of refraction and / or absorption and / or reflection is below 5% and preferably below 1% and particularly preferably below 0.1%. Furthermore, the produced layer 145 or the further produced layers 145 can preferably be metal-free.

[0154] Fig. 1c shows a schematic of the creation of modifications 9 using laser beams. The laser beams preferably penetrate into the solid body 1 via the layer 145 previously created using the high-temperature process. Alternatively, however, it is also conceivable for the laser beams to penetrate into the solid body 1 via a free surface of the solid body 1, i.e., a surface not coated with the additional layer 145, in particular from below. In this case, the solid body 1 is preferably held laterally or at the outer ends (width and / or depth direction).

[0155] Fig. 1d shows a schematic sectional view of the solid body 1 after the creation of the modifications 9. According to this example, four blocks of modifications 9 are recognizable, which lead to the four crack portions 25, 27, 28, 29. Adjacent to the blocks with modifications 9, the reference numerals 41, 42, 43, 44, and 45 respectively denote regions without modifications 9 or regions in which fewer modifications 9 are created than in the regions in which the blocks of modifications 9 are created.

[0156] Fig. 1e shows a state according to which a receiving layer, in particular comprising a polymer material, is arranged or produced on further components (not shown) arranged on the surface 5 or on a further layer previously epitaxially produced on the surface 5. The receiving layer is preferably produced as a film and, after its production, is coupled, in particular bonded or glued, to the surface 5. However, it is also possible to form the receiving layer by applying a liquid polymer to the surface 5 and subsequently solidifying it.

[0157] Between the step of producing the modifications and the application of the receiving layer, an arrangement or production of further layers 150 and / or components 150 preferably takes place on the surface 5 or on a further layer 145 already produced thereon during a preceding high-temperature process.

[0158] Fig. 1f shows a schematic representation of the temperature control of the receiving layer. Preferably, the receiving layer is temperature-controlled, in particular cooled, to a temperature below ambient temperature, in particular to a temperature of less than 20°C, or less than 1°C, or less than 0°C, or less than -10°C, or less than -50°C, or less than -60°C. The material of the receiving layer 140 undergoes a glass transition or crystallization as a result of the cooling. The temperature control of the receiving layer is preferably carried out using liquid nitrogen, in particular using a nitrogen mist. Due to the temperature control, in particular due to the glass transition, the receiving layer contracts, thereby generating mechanical stresses in the solid body 1. Due to the mechanical stresses, a crack connecting the crack portions 25, 27, 28, 29 is triggered, through which the solid body portion 12 is separated from the solid body 1.

[0159] Fig. 2a shows an embodiment according to which the receiving layer 140 is arranged on a surface of the solid body which is further spaced from the modifications than a surface 5 parallel thereto or preferably substantially parallel or completely parallel thereto. Preferably, the surface has a further layer 145 (analogous to Fig. 1b-1f ). Components 150 or further material layers 150 are preferably arranged on the further layer 145 or on the exposed surface 5. A stabilization layer and / or a protective layer 142 is preferably arranged or produced on an exposed surface of the further material layer 150 or of the components 150. The components 150 can, for example, be cast, in particular with a polymer material and / or ceramic material. It is also conceivable that a stabilization device, in particular a further wafer, such as a glass wafer, is coupled, in particular glued or bonded, to the stabilization layer and / or protective layer 142. The stabilization layer and / or protective layer 142 or the stabilization layer and / or protective layer 142 and the stabilization device cause the components 150 orThe further material layer 150 deforms only slightly or not at all during or after separation. During separation, the deformation can be caused by the forces generated by the receiving layer 140, and after separation, deformation can be caused by the remaining modifications, in particular material transformations. In the event of a material transformation, the modifications cause compressive forces to arise, which, without the stabilizing layer / stabilizing device, would result in a warpage (BOW) of the separated solid layer.

[0160] A unit comprising the separated solid layer and the stabilizing layer and / or protective layer 142 arranged thereon, and any stabilizing device arranged thereon, is then preferably further treated for stress removal. Particularly preferably, the stabilizing layer 142 or the stabilizing device forms a holding device by means of which the separated solid layer can be fixed relative to a material removal device, in particular a grinding and / or polishing device, for a material removal treatment. The modification components remaining on the separated solid layer are then removed, in particular by machining, by means of the material removal device.

[0161] In the context of this invention, the solid layer is preferably always thinner than the remaining solid portion. However, it is also conceivable for the receiving layer to be arranged or created not on a surface of the subsequent solid layer, but on a surface of the remaining solid portion. If the solid material is silicon, then the separated solid layer preferably has a height of less than 40% of the height of the remaining solid, in particular less than 30% or 20% of the height of the remaining solid.In the case of silicon, predetermined parameters are preferably provided for the modification generation, the numerical aperture is preferably between 0.5 and 0.8, in particular 0.65, the irradiation depth is between 150µm and 1000µm, in particular 300µm, the pulse spacing is between 1µm and 5µm, in particular 2µm, the line spacing is between 1µm and 5µm, in particular 2µm, the pulse duration is between 50ns and 400ns, in particular 300ns, and the pulse energy is between 3µJ and 30µJ, in particular 10µJ.

[0162] If the material is SiC, the separated solid layer preferably has a height of less than 50% of the height of the remaining solid, in particular less than 45% or 40% or 35% or 30% or 25% of the height of the remaining solid. In the case of SiC, predetermined parameters are preferably provided for the modification generation, the numerical aperture is preferably between 0.4 and 0.8, in particular 0.4, the irradiation depth is preferably between 50 µm and 500 µm, in particular 180 µm, the pulse spacing is preferably between 0.1 µm and 3 µm, in particular 1 µm, the line spacing is preferably between 10 µm and 100 µm, in particular 75 µm, the pulse duration is preferably between 1 fs and 10 ns, in particular 3 ns, and the pulse energy is preferably between 0.5 µJ and 30 µJ, in particular 7 µJ.

[0163] Also in Fig. 2b can be analogous to the Fig. 1b-1f A further layer 145 may be created, even if it has not been identified. The further material layers or components 150 are therefore preferably created or arranged on the further layer 145 or on an exposed surface of the solid body.

[0164] Furthermore, Fig. 2b that the receiving layer can be arranged on a surface of the remaining solid body and a further receiving layer 146 can be arranged on the components or further material layers 150. The components can additionally be provided with a stabilization layer 142, whereby the further receiving layer 146 is preferably arranged or produced on the stabilization layer and / or protective layer 142. The further receiving layer 146 is preferably provided as a film and preferably also consists at least partially of a polymer material. Particularly preferably, the further receiving layer 146 comprises the same material as the receiving layer 140 or 142. This embodiment is advantageous because the stresses for generating the crack can be introduced into the solid body from two sides.

[0165] The Figuren 3a bis 3i show various arrangements that can be provided after the production of the further material layers or components 150 for initiating the crack.

[0166] The Figuren 3a-3i show various solid arrangements 176 which are advantageous for introducing crack guiding and / or crack initiation stresses.

[0167] Fig. 3a shows a processed solid body 1 or wafer with structures or components 150.

[0168] Compared to the Fig. 3a The solid 1 shown in Fig. 3b In the solid body 1 shown, a receiving layer 140 is arranged or produced on the component side, in particular on the components 150 or the additional material layers 150. The receiving layer 140 is preferably arranged on the solid layer to be separated. The receiving layer 140 can also be referred to as a split film and is thus preferably laminated to the structural side. In the subsequent step, the entire arrangement is then cooled, causing the split or crack initiation and / or crack guidance.

[0169] Compared to the representation of the Fig. 3b is according to the Fig. 3c A holding layer / bonded wafer is arranged on the underside of the solid body or on the exposed surface of the solid body. The holding layer can also be a tool carrier or chuck 3. In the subsequent step, the entire assembly is cooled, which causes the split or crack initiation and / or crack guidance.

[0170] Fig. 3d shows opposite the Fig. 3b an arrangement according to which the solid body is provided with receiving layers 140, 146 on both sides. The further receiving layer 146 is arranged on a surface of the remaining solid body, wherein an adhesion-promoting layer 148 and / or sacrificial layer 149 and / or protective layer 142 can be arranged or created between the further receiving layer 146 and the solid body 1. The two receiving layers 140 and 146 are preferably laminated. In the subsequent step, the entire arrangement is cooled, which causes the split or crack initiation and / or crack guidance.

[0171] Fig. 3e shows an arrangement according to which, compared to the Fig. 3d In the known arrangement, no adhesion-promoting layer 148 and / or sacrificial layer 149 and / or protective layer 142 is arranged or produced between the further receiving layer 146 and the solid body 1. In the subsequent step, the entire arrangement is then cooled, causing the split or crack initiation and / or crack guidance.

[0172] Fig. 3f shows an arrangement that is inverse to that of Fig. 3d known arrangement, ie the adhesion-promoting layer 148 and / or sacrificial layer 149 and / or protective layer 142 is not arranged or produced between the further receiving layer 146 and the solid body 1, but is / are arranged or produced between the receiving layer 140 and the solid body 1 and thus is / are produced or arranged on the solid body layer to be separated. One or more layers can be produced on the components 150 or the structures, for example by means of spin coating. The subsequent step is then cooling the entire arrangement, which causes the split or the crack initiation and / or crack guidance.

[0173] Fig. 3g shows an arrangement or characteristic that is a combination of the arrangements of the Figuren 3d und 3f The solid body is preferably laminated on both sides with split film. A protective layer and / or adhesion-promoting layer and / or sacrificial layer can also be provided on both sides beneath the split film. Spin coating, for example, is also possible on the structures. The subsequent step is cooling the entire assembly, which causes the split or crack initiation and / or crack propagation.

[0174] Fig. 3h shows an arrangement similar to that shown in Fig. 3b The arrangement shown is that the receiving layer is not arranged or laminated on a surface of the solid layer to be separated, but rather on the residual solid remaining after separation. The separation then occurs as a result of cooling, analogous to the separation from an ingot or as in an ingot process.

[0175] Fig. 3i shows an arrangement similar to that of Fig. 3c known arrangement, wherein one or more of the following layers or devices is / are arranged or produced on the component side of the solid body or on or above the components 150. These layers or devices are preferred: at least or exactly one adhesion-promoting layer 148 and / or at least or exactly one sacrificial layer 149 and / or at least or exactly one protective layer 142 and / or at least or exactly one stabilizing device 3, in particular a tool carrier or chuck or another wafer. The subsequent step is then cooling the entire arrangement, which causes the split or crack initiation and / or crack guidance.

[0176] Fig. 4 shows an illustration of an example of a writing pattern during XY machining: Arrows 170, 172 represent the laser feed direction, the black circles represent the different laser shots or modifications 9, which do not overlap in their damaging effect on the material. It is preferable for the laser to first move in one direction and create modifications 9 before reversing and writing modifications 9 in the second (lower) direction.

[0177] The Figuren 5a bis 5d show various cooling devices 174. The solid state arrangements 176 processed in these cooling devices 174 result from the various Figuren 1a bis 3i The embodiments or designs shown and described of the solid bodies 1 provided with one or more receiving layers 140, 146 are shown. The cooling devices 174 shown here all use a liquefied gas 178 as the starting cooling medium for cooling. This starting cooling medium is either nebulized or vaporized, depending on the embodiment. The starting cooling medium is preferably liquid nitrogen. Alternative cooling methods, e.g., using Peltier elements, are also conceivable and possible.

[0178] The cooling device 174 preferably serves to cool the receiving layer 140, 146 to a temperature between -130°C and -10°C, in particular to a temperature between -80°C and -50°C.

[0179] According to Fig. 5a The cooling device 174 comprises a nitrogen bath, wherein the receiving layer is positioned at a distance, in particular by means of an adjustable positioning device 180, from the liquid nitrogen held in the nitrogen bath. Thus, the solid-state arrangement is preferably arranged on a positioning device or on a holder above a nitrogen bath. This results in a temperature gradient across the chamber height, and the temperature at the solid-state arrangement can be adjusted via the fill level with the initial cooling medium or the position of the solid-state arrangement 176 (distance from the bottom of the chamber).

[0180] According to the embodiments of the Figuren 5b bis 5d the cooling device can preferably comprise a nebulizing means, in particular at least or exactly one perforated pipe, for nebulizing liquid nitrogen or a nebulizing means for nebulizing liquid nitrogen and the cooling effect can be generated by nebulized or vaporized nitrogen.

[0181] According to Fig. 5b A homogeneous spray device / fogger is preferably provided for spraying or atomizing. The spraying or atomizing preferably takes place above the solid-state arrangement 176. Furthermore, temperature measurements are preferably performed for temperature control, which output data for controlling a valve, in particular a nitrogen valve. The temperature measurements are preferably performed on the substrate or on the solid-state 1 or on the receiving layer 140.

[0182] The substrate or the solid body 1 or the solid body arrangement 176 preferably rests above the chamber floor in order to avoid nitrogen settling at the bottom of the chamber.

[0183] According to Fig. 5c A perforated pipeline is preferably used as a homogeneous spray device. Furthermore, temperature measurements are preferably performed for temperature control, which provide output data for controlling a valve, in particular a nitrogen valve. The temperature measurements are preferably performed on the substrate or on the solid body 1 or on the receiving layer 140.

[0184] The substrate or the solid body 1 or the solid body arrangement 176 preferably rests above the chamber floor in order to avoid nitrogen settling at the bottom of the chamber.

[0185] According to Fig. 5d shows a cooling device 176 that has a homogeneous sprayer / fogger 182 for cooling preferably several or each side. Furthermore, temperature measurements are preferably performed for temperature control, which output data for controlling a valve, in particular a nitrogen valve. The temperature measurements are preferably performed on the substrate or on the solid body 1 or on the receiving layer 140.

[0186] The substrate or the solid body 1 or the solid body arrangement 176 preferably rests above the chamber floor in order to avoid nitrogen settling at the bottom of the chamber.

[0187] The chamber 184 of the cooling device 174 is preferably closed in order to reduce a temperature gradient as much as possible by insulation.

[0188] Fig. 6 shows three examples of preferred relationships between crystal lattice orientation and modification generation. This method is particularly useful for separating solid layers from a solid consisting of SiC or containing SiC. These relationships result in a further method according to the invention. This further method according to the invention is preferably used for separating at least one solid layer 4 from at least one solid 1, in particular from a wafer from an ingot or for thinning a wafer.The further method according to the invention preferably comprises at least the steps: generating a plurality of modifications 9 by means of laser beams in the interior of the solid body 1 to form a detachment plane 8, and introducing an external force into the solid body 1 to generate stresses in the solid body 1, wherein the external force is so strong that the stresses cause crack propagation along the detachment plane 8.

[0189] According to the invention, the modifications are produced one after the other in at least one row or series or line, wherein the modifications 9 produced in a row or series or line are preferably produced at a distance X and with a height H, so that a crack propagating between two successive modifications, in particular a crack propagating in the crystal lattice direction, the crack propagation direction of which is oriented at an angle W to the detachment plane, connects the two modifications to one another. The angle W is preferably between 0° and 6°, in particular 4°. The crack preferably propagates from an area below the center of a first modification to an area above the center of a second modification. The essential relationship here is therefore that the size of the modification can or must be changed depending on the distance between the modifications and the angle W.

[0190] Furthermore, this method can also comprise the step of creating a composite structure by arranging or creating layers and / or components 150 on or above an initially exposed surface 5 of the solid body 1, wherein the exposed surface 5 is preferably a component of the solid body layer 4 to be separated. Particularly preferably, the modifications for forming the detachment plane 8 are created before the creation of the composite structure.

[0191] To introduce the external force, a receiving layer 140 can be arranged on an exposed surface 5 of the composite structure or the solid body, for example, analogously to the previously described methods.

[0192] The three figures 6a to 6c illustrate how the size of the laser-amorphized / phase-transformed damage / modification zone influences the height traversed by the sawtooth pattern of the crack. Generally, the crack runs along the crystal planes, i.e., between individual atoms of the crystal. In the modified zone, these clear planes no longer exist, so the crack stops.

[0193] By preferably using the highest possible numerical aperture, the damage zone can be reduced along the beam direction, as well as laterally in the focal plane. Since only the threshold intensity needs to be reached, a lower pulse energy is sufficient.

[0194] If the damaged area is suitably smaller, the laser modifications can be placed more densely, which makes the sawtooth run shorter and results in an overall smaller height extension of the modified plane (first image).

[0195] However, if the damage zone is larger (higher energy and / or lower numerical aperture - Fig. 6b ) - the increased pressure of the amorphized zone also triggers a larger microcrack, which can be captured (ie stopped in a controlled manner) by a damage zone of greater extent at a greater distance.

[0196] Fig. 6c Finally, the danger arises when the damaged area is not sufficiently large and excessive cracks are triggered by the laser modification. Firstly, the cracks extend too far – meaning the height difference caused by the cracks is greater than desired – and secondly, the cracks are driven beneath the other damaged areas and not stopped by the amorphized material. This then leads to material loss, as all torn material layers must be removed for the final product or for further laser processing.

[0197] Fig. 7 shows a schematically illustrated snapshot from a further method according to the invention. This further method is preferably used to separate at least one solid layer 4 from at least one solid body 1, in particular from a wafer from an ingot or for thinning a wafer. The further method according to the invention preferably comprises at least the steps: generating a plurality of modifications 9 by means of laser beams in the interior of the solid body 1 to form a detachment plane 8, and introducing an external force into the solid body 1 to generate stresses in the solid body 1, wherein the external force is so strong that the stresses cause crack propagation along the detachment plane 8.

[0198] According to the invention, in a first step the modifications are produced on a line 103 and preferably at the same distance from one another. Furthermore, it is conceivable that a plurality of these lines produced in the first step are produced. These first lines are particularly preferably produced parallel to the crack propagation direction and preferably in a straight line or in the shape of a circular arc, in particular in the same plane. After the production of these first lines, second lines 105 are preferably produced for initiating and / or driving preferably subcritical cracks. These second lines are also preferably produced in a straight line. The second lines are particularly preferably inclined with respect to the first lines, in particular oriented orthogonally. The second lines preferably extend in the same plane as the first lines or particularly preferably in a plane that is parallel to the plane in which the first lines extend.Subsequently, third lines are preferably created to connect the subcritical cracks.

[0199] This process is particularly useful for separating solid layers from a solid made of SIC or containing SiC.

[0200] Furthermore, the modifications can be produced one after the other in at least one row, series or line, wherein the modifications 9 produced in a row, series or line are preferably produced at a distance X and with a height H, so that a crack propagating between two successive modifications, in particular a crack propagating in the crystal lattice direction, the crack propagation direction of which is oriented at an angle W to the detachment plane, connects the two modifications to one another. The angle W is preferably between 0° and 6°, in particular 4°. The crack preferably propagates from an area below the center of a first modification to an area above the center of a second modification. The essential relationship here is therefore that the size of the modification can or must be changed depending on the distance between the modifications and the angle W.

[0201] Furthermore, this method can also comprise the step of creating a composite structure by arranging or creating layers and / or components 150 on or above an initially exposed surface 5 of the solid body 1, wherein the exposed surface 5 is preferably a component of the solid body layer 4 to be separated. Particularly preferably, the modifications for forming the detachment plane 8 are created before the creation of the composite structure.

[0202] To introduce the external force, a receiving layer 140 can be arranged on an exposed surface 5 of the composite structure or the solid body, for example, analogously to the previously described methods.

[0203] Thus, in the further laser process according to the invention, lines parallel to the crack propagation direction (preferably called transverse lines) are generated, preferably on SiC (but also on other materials), to first define a plane for preferential crack initiation (crack initiation) before longitudinal lines drive the cracks. The cracks are first initialized transversely, then longitudinally, before a final step inserts lines between the longitudinal lines of the second step to initiate the cracks across the entire surface. This enables shorter crack propagation paths, which minimizes the final surface roughness. Example image for transverse lines (with the sawtooth) and crack initiation lines (on the wave crests of the sawtooth).

[0204] Fig. 8 shows an example of a Schottky diode 200. This diode 200 preferably has a solid-state layer 4, which in turn has portions modified by laser radiation, in particular modifications 9. The modifications 9 are produced in the vicinity of a first surface of the solid-state layer 4. A metal layer 20 has preferably been produced on this first surface of the solid-state layer 4, in particular by sputtering or chemical deposition. The solid-state layer 4 has a second surface opposite the first surface, on which a further layer 145 is produced, in particular by means of an epitaxial process. The solid-state layer 4 preferably consists of highly doped SiC or has highly doped SiC, and the produced layer 145 preferably consists of weakly doped SiC or has weakly doped SiC. Weakly doped here preferably means less doped than highly doped.Thus, the produced layer 145 preferably has less doping per unit volume than the solid-state layer 4. The reference numeral 150 denotes a Schottky contact.

[0205] Fig. 9shows an example of the structure of a MOSFET 250. This MOSFET 250 preferably has a solid-state layer 4, which in turn has portions modified by laser radiation, in particular modifications 9. The modifications 9 are produced in the vicinity of a first surface of the solid-state layer 4. A metal layer 20 has preferably been produced on this first surface of the solid-state layer 4, in particular by sputtering or chemical deposition. The metal layer 20 preferably forms a drain (high) via a connection 259. The solid-state layer 4 has a second surface opposite the first surface. A further layer, in particular n-type SiC, is formed, in particular produced or arranged on the second surface. The reference numeral 256 denotes a further material or element, in particular p-type SiC. The reference numeral 254 stands for n+.Reference numeral 255 preferably designates one or more channels, in particular for conducting current. The layer / view designated by reference numeral 253 preferably consists of or comprises SiO2. Reference numeral 251 designates a source (low), and reference numeral 252 designates a gate.

[0206] The present invention can thus relate to a method for providing at least one solid layer 4, wherein the solid layer 4 is separated from a solid 1. The method according to the invention preferably comprises the steps of: generating a plurality of modifications 9 by means of laser beams inside the solid 1 to form a detachment plane 8, wherein compressive stresses are generated in the solid 1 by the modifications 9, separating the solid layer 4 by separating the remaining solid 1 and the solid layer 4 along the detachment plane 8 formed by the modifications 9, wherein at least components of the modifications 9 generating the compressive stresses remain on the solid layer 4, wherein as many modifications 9 are generated,that the solid layer 4 detaches from the solid body 1 due to the modifications 9 or wherein an external force is introduced into the solid body 1 to generate further stresses in the solid body 1, wherein the external force is so strong that the stresses cause crack propagation along the detachment plane 8 formed by the modifications, generating a metal layer on the surface exposed by the separation of the solid layer 4 from the solid body 1 to at least partially and preferably mostly and particularly preferably completely compensate for a deformation of the solid layer 4 caused by the compressive stresses of the remaining modification components or to at least partially and preferably mostly or completely compensate for the compressive stresses, see claim 1.,

[0207] Furthermore, the present invention may relate to a method for producing electrical components using the method according to claim 1, see claim 2.

Claims

1. Method for providing at least one solid-state layer (4), wherein the solid-state layer (4) is separated from a solid body (1) and wherein the method at least comprises: generating a plurality of modifications (9) by means of laser beams inside the solid body (1) in order to form a separation plane (8), wherein compressive stresses are generated in the solid body (1) by the modifications (9), separating the solid-state layer (4) by a separation of the remaining solid body (1) and the solid-state layer (4) along the separation plane (8) formed by the modifications (9), wherein at least portions of the modifications (9) generating the compressive stresses remain on the solid-state layer (4), wherein so many modifications (9) are generated that the solid-state layer (4) separates from the solid body (1) due to the modifications (9) or wherein an external force is introduced into the solid body (1) in order to generate further stresses in the solid body (1), wherein the external force is so strong that the stresses cause a crack propagation along the separation plane (8) formed by the modifications, wherein the method is characterized by generating a metal layer (20) on the surface exposed by the separation of the solid-state layer (4) from the solid body (1) for at least partially and preferably predominantly and particularly preferably completely compensating a deformation of the solid-state layer (4) caused by the compressive stresses of the remaining modification portions, or for at least partially and preferably predominantly or completely compensating the compressive stresses.

2. Method according to claim 1, for generating electrical components, wherein the method further comprises: generating a composite structure by arranging or generating layers and / or components (150) on or above an initially exposed surface (5) of the solid body (1), wherein the exposed surface (5) is a portion of the solid-state layer (4) to be separated.

3. Method according to claim 1 or 2, wherein the metal layer is generated on the solid-state layer (4) in a first aggregate state and a temperature above room temperature and is present in a second aggregate state at room temperature, wherein, due to the transition from the first aggregate state to the second aggregate state, the metal layer acts on the solid-state layer in order to at least partially compensate and preferably completely compensate the deformation caused by the compressive stresses of the remaining modification portions, or the metal layer is generated on the solid-state layer (4) in a temperature range above room temperature, wherein the temperature range is at least 100°C or 150°C or 200°C or 250°C or 300°C or 350°C or 400°C above room temperature and particularly preferably up to a maximum of 2000°C or less than the melting or evaporation temperature of the solid-state material, wherein, due to the cooling of the metal layer to room temperature, the solid-state layer acts on the solid-state layer in order to at least partially compensate and preferably completely compensate the deformation caused by the compressive stresses of the remaining modification portions.

4. Method according to one of the preceding claims, wherein the metal layer is generated by sputtering or electrochemical deposition.

5. Method according to one of the preceding claims, wherein the solid body consists of silicon carbide, SiC, or comprises SiC, wherein the solid-state layer (4) is separated from the solid body (1) with a thickness of less than 200 µm, in particular with a thickness of less than 150 µm or of less than 125 µm or of less than 110 µm or of less than 100 µm or of less than 90 µm or of less than 75 µm.

6. Method according to claim 5, wherein a numerical aperture is between 0.4 and 0.8, in particular at 0.4, an irradiation depth is between 50 µm and 500 µm, in particular at 180 µm, a pulse spacing is between 0.1 µm and 3 µm, in particular at 1 µm, a line spacing is between 10 µm and 100 µm, in particular at 75 µm, a pulse duration is between 100 fs and 10 ns, in particular at 3 ns or between 3 ns and 0.2 ns, in particular between 2 ns and 0.5 ns or between 1.5 ns and 0.6 ns, and a pulse energy is between 0.5 µJ and 30 µJ, in particular at 7 µJ.

7. Method according to one of claims 2 to 6, wherein the electrical components are vertical components, in particular Schottky diodes (200) and / or metal oxide semiconductor field effect transistors (MOSFETs) (250), and wherein the metal layer forms an electrical contact, in particular an ohmic contact, and / or forms an interface for heat dissipation.

8. Method according to one of claims 2 to 6, wherein the electrical components are lateral components, in particular high electron mobility transistors, HEMTs, and wherein the metal layer preferably forms an interface for heat dissipation.

9. Method according to one of claims 2 to 8, wherein a plurality, in particular at least 10 or at least 50 or at least 100, of electrical components is generated on average per cm2 of a planar surface side of the solid-state layer, and wherein the electrical components are separated from one another by means of dicing after their generation.

10. Method according to one of the preceding claims, wherein a receiving layer (140) is arranged on an exposed surface (5) of the composite structure or of the solid-state layer (4) to be separated in order to introduce the external force, wherein the receiving layer (140) comprises a polymer material and the receiving layer (140) is acted on thermally in order to generate, in particular mechanically, stresses in the solid body (2), wherein the thermal application represents a cooling of the receiving layer to a temperature below the ambient temperature, wherein the cooling takes place in such a way that the polymer material of the receiving layer (140) undergoes a glass transition and wherein a crack propagates in the solid body (2) along the separation plane (8) as a result of the stresses, which crack separates the solid-state layer (4) from the solid body (2).

11. Method according to one of the preceding claims, wherein the solid body (1) is treated with at least one high-temperature method before the generation of the separation plane (8), wherein the high-temperature method is carried out with a temperature between 70°C and the melting temperature or evaporation temperature of the material of the solid body (1), wherein the at least one high-temperature method is an epitaxy method, a doping method or a method using plasma, wherein at least one layer (145) is generated on the solid body (1) by the high-temperature method, wherein the at least one generated layer (145) has predefined parameters, wherein at least one predefined parameter specifies a maximum degree of refraction and / or absorption and / or reflection of laser light waves, and wherein the degree of refraction and / or absorption and / or reflection is below 5% and preferably below 1% and particularly preferably below 0.1%.

12. Method according to one of the preceding claims, wherein the modifications (9) are generated by means of multi-photon excitation, wherein firstly a plurality of base modifications are generated on a line, in particular a curved line, which runs homogeneously at least in sections, in particular in the homogeneously running section, wherein these base modifications are generated with predefined process parameters, wherein the predefined process parameters preferably comprise the energy per shot and / or the shot density, wherein at least one value of these process parameters and preferably both values or all values of these process parameters or more than two values of these process parameters is / are fixed depending on the crystal lattice stability of the solid body, wherein the value is selected such that the crystal lattice remains intact around the respective base modifications, wherein furthermore triggering modifications for triggering subcritical cracks are generated, wherein at least one process parameter for generating the triggering modifications is different from at least one process parameter for generating the base modifications, preferably a plurality of process parameters are different from one another, and / or the triggering modifications are generated in a direction which is inclined or spaced apart from the running direction of the line along which the base modifications are generated, and wherein the subcritical cracks propagate less than 5 mm.

13. Method according to claim 12, wherein the subcritical cracks propagate in the solid body between 5 µm and 200 µm, in particular between 10 µm and 100 µm or between 10 µm and 50 µm or between 10 µm and 30 µm or between 20 µm and 100 µm or between 20 µm and 50 µm or between 20 µm and 30 µm, and / or sections between the regions of a plurality of lines in which the subcritical cracks have propagated tear in as a result of the stresses which are generated by the glass transition.

14. Method according to one of the preceding claims, wherein a stabilizing layer (142) for limiting deformations of the exposed layer or of the exposed components (150) is arranged or generated on the exposed surface or the exposed layer or the exposed components (150) of the generated composite structure, wherein the deformations result from the mechanical stresses introduced by means of the receiving layer (150), wherein the stabilizing layer (142) preferably comprises a ceramic material or consists of a ceramic material and / or comprises a polymer material or consists of a polymer material, the stabilizing layer (142) is preferably generated in-situ or is provided as a film and / or the stabilizing layer (142) preferably casts in the layer or the exposed components (150) and / or the stabilizing layer (142) is preferably removed from the layer or removed from the components (150) by application of a solvent or by immersion in a solvent.

15. Multi-component arrangement which comprises at least one solid-state layer, wherein the solid-state layer consists of SiC to an extent of more than 50% (by mass), in particular to an extent of more than 75% (by mass) or to an extent of more than 90% (by mass) or to an extent of more than 95% (by mass) or to an extent of more than 98% (by mass) or to an extent of more than 99% (by mass), wherein the solid-state layer comprises modifications or modification portions which generate compressive stresses in the region of a first surface, wherein the modifications are amorphized portions of the solid-state layer, wherein the modifications are spaced apart closer to the first surface, or also form the latter, than to a second surface, wherein the second surface is formed parallel or substantially parallel to the first surface, wherein the first surface is planar or substantially planar, characterized in that the multi-component arrangement further comprises a metal layer, wherein the metal layer is generated on the first surface of the solid-state layer, and wherein the first surface is formed by separating the solid-state layer from a solid body.