Method for separating a total substrate into a first substrate and a second substrate, and device for a method of this type

Abstract

The invention relates to a method for separating a total substrate (3) into a first substrate (13) and a second substrate (23), wherein the first substrate (13) and / or the second substrate (23) is intended as a component of an electronic device, comprising: providing the total substrate (3), comprising the first substrate (13) and the second substrate (23), wherein the first substrate (13) and the second substrate (23) are connected to one another along a bonding interface via a created bond, preferably via a connection created by a fusion bond; and separating the total substrate (3) into the first substrate (13) and the second substrate (23) along the bonding interface, wherein a chemical processing agent and preferably a non-chemical agent are used to separate the total substrate (3) into the first substrate (13) and the second substrate (23).

Description

[0001] Method for separating a total substrate into a first substrate and a second substrate and device for such a method

[0002] The present invention relates to a method for separating an entire substrate into a first substrate and a second substrate and to a device for such a method.

[0003] With advancing miniaturization, there is a growing need for more powerful, smaller, thinner and faster electronic devices, which require correspondingly smaller, thinner, more powerful and faster chips.

[0004] To increase chip performance, the computing power of the chips is increased, following Moore's observation. This involves smaller chips with a large number of feedthroughs and contacts, and in particular, chips are manufactured in stacks of layers of identical or different circuits.

[0005] For stacking the layers, thin-film technology can be used at the transistor level, or finished, thinned chips or substrates can be aligned with each other and joined, in particular bonded, together.

[0006] Hybrid bond and fusion bond technology, which is primarily used for the production of SOI substrates, memory units, MEMS components, or image sensors, requires continuously improved quality control of the joined substrates. Fusion bonds and / or hybrid bonds hold the substrates together in the prebond process primarily through van der Waals forces. A subsequent heat treatment permanently bonds the joined substrate. In the case of a hybrid bond, the metallic feedthroughs and contacts are bonded together during the heat treatment. During the quality control of the prebond, alignment errors, particles, or gas inclusions can be detected, which would lead to intolerable defects that require correction.

[0007] With permanent bonding processes, correction of the bonded entire substrate is not possible, so only the defective substrates or chips can be separated. Fusion-bonded entire substrates in the prebond process can be separated from each other non-destructively, allowing the substrates to be rejoined after separation. In the prior art, fusion-bonded entire substrates have been separated for several years using so-called debonding processes, as disclosed, for example, in US Pat. No. 9,806,054 B2.

[0008] The separation of the entire substrate joined by fusion bonding in the prebond and the rejoining proves to be a technologically and financially sensible option compared to the separation of entire substrates, especially if the substrates are assigned to a different pairing in order to compensate for the incorrect alignment or distortions measured on the entire substrate that exceed the tolerance values.

[0009] The separated substrates are subjected to cleaning and optionally renewed surface activation, then realigned to each other and bonded together by fusion bonding.

[0010] The bond strength of fusion-bonded substrates has been continuously increased in recent years because the substrates are held together with optimized surface activation by means of plasma treatment with increased bond strength in the prebond.

[0011] Plasma activation ensures, in particular, that a reservoir is created in at least one of the two substrates in which a fluid, in particular water, can be stored. This stored water results in several physical and chemical changes after bonding of the two substrates, which can lead to an improvement in bond strength even at relatively low temperatures. These effects are explained in detail in the publications WO2012100786A1, WO2012136267A1, WO2012136268A1, WO2012136266A1, and WO2014015899A1.

[0012] Subsequent heat treatment to achieve the final bond strength can thus be performed at lower temperatures and / or in a shorter time. The increased strength of the prebond reduces the chance of non-destructively opening the faulty bonded substrate.

[0013] The approaches of mechanically detaching a first substrate from the second substrate, which are also used in temporary bonding and debonding, as disclosed in US 9,296,193 B2 or in US 9,922,862 B2, cannot be adapted without restriction without risking substrate fracture.

[0014] The object of the present invention is therefore to demonstrate a modified debonding method for fusion-bonded substrates in which stronger prebonds can be separated.

[0015] The present invention solves this problem with a method according to claim 1 and a device according to claim 13. Further advantageous embodiments can be found in the description, the dependent claims, and the figures. The scope of the invention also includes all combinations of at least two of the features specified in the description, the claims, and / or the drawings. In the case of value ranges, values ​​within the stated limits should also be disclosed as limit values ​​and claimable in any combination.

[0016] According to a first aspect, a method is provided for separating an overall substrate into a first substrate and a second substrate, wherein the first substrate and / or the second substrate is provided or intended as a component of an electronic or electromechanical device, comprising:

[0017] Providing the overall substrate comprising the first substrate and the second substrate, wherein the first substrate and the second substrate are connected to one another via a generated connection, preferably via a connection generated by a fusion bond, along a bonding interface, wherein the overall substrate is a non-destructively detachable connection, in particular a prebond, and

[0018] - Separating the entire substrate into the first substrate and the second substrate along the bonding interface, wherein a means for chemical processing and preferably a means for non-chemical processing is used to separate the entire substrate into the first substrate and the second substrate. Compared to the methods known from the prior art, the invention provides that a means for chemical processing is used and in particular is combined with a means for non-chemical processing when separating along the bonding interface. The means for chemical processing and the means for non-chemical processing preferably act simultaneously or sequentially together on the bonding interface of the entire substrate. The first substrate and the second substrate are connected to one another via the bonding interface in the entire substrate.It has been shown that this allows the separation to be carried out in a more controlled manner, i.e. largely without uncontrolled breakage. In particular, it has been found that a mechanical separation force, which emanates in particular from the means for non-chemical processing, can be increased with the effect of a chemical solvent during the separation of a fusion-bonded overall substrate, and as a result the bonds of a prebond can be broken. This reduces the mechanical separation force required for separation and decreases the risk of substrate breakage. This ensures that the first substrate and / or the second substrate can be reused even after separation. For example, the first substrate and the second substrate can be joined together again. Furthermore, the separation process can be accelerated.As a means for non-chemical processing, an optical means, for example using laser light, a means for irradiation, for example with light or particles, in particular ions, and / or a mechanical means, for example in which a cutting edge acts on a region of the bonding interface to separate it along a separation plane or along the bonding interface, are also conceivable. The means for non-chemical processing can be a system, in particular a substrate holder system, which, for example, causes the first substrate and the second substrate to be pulled apart. The means for non-chemical processing preferably causes a separating force that acts mechanically on the first substrate and the second substrate.This is achieved, for example, by substrate holders that are attached to the first substrate and the second substrate, if the first substrate and the second substrate are still connected to each other via the bonding interface in the overall substrate. In this case, the non-chemical, particularly mechanical, means is formed by the first substrate holder and / or the second substrate holder, which exert a mechanical separation force upon separation.

[0019] The entire substrate is preferably a fusion bond that can be separated non-destructively without heat treatment. The prebond describes a state of the fusion bond in which the two substrates are bonded together solely by van der Waals forces. This bonding process primarily takes place between silicon substrates and / or silicon oxide substrates or other non-metallic, preferably dielectric substrates, preferably semiconductor substrates. The bond produced in this way is referred to as a prebond because it is a precursor to a permanent connection. In the semiconductor industry, it is very often desirable to undo a (temporary) connection created by a prebond if it is discovered after joining that the two substrates were not optimally aligned or were even incorrectly aligned. The separation preferably takes place along a separation plane that runs along a bonding interface orthe bonding interface, which runs between the first and second substrates and is particularly preferably created or formed by fusion bonding. The bonding interface thus differs from the first substrate and / or second substrate in terms of its physical and / or chemical properties. This separation plane or bonding interface particularly preferably runs along a plane parallel to the main extension plane of the substrates, wherein the main extension plane is predetermined by a general course of the entire substrate, the first substrate, and the second substrate. The chemical bonds that exist between the two bonded substrates are at least partially broken using a solvent.The solvent acts on the existing bonds between the substrate surfaces of the entire substrate to be separated, thereby reducing the separation force, particularly the mechanical one, required for complete debonding. In particular, the solvent has a locally corrosive effect on the prebond bonds, causing a type of stress corrosion to facilitate separation along the separation plane.

[0020] According to the invention, it is conceivable to use a fluid, i.e. gases and / or liquids, as a means for chemical processing.

[0021] An electrical component is understood to be, for example, a chip or a component of a printed circuit board. In particular, the electrical component comprises electrical vias and / or electrical connections. The electrical component preferably further comprises a conductor track structure.

[0022] For example, it is provided that the first substrate and the second substrate are reconnected to one another after separation, preferably via a fusion bond. This advantageously makes it possible to incorporate the separation method into a correction mechanism in which an unwanted offset between the first substrate and the second substrate was detected and separation was subsequently required for correction. Furthermore, it is advantageously possible to incorporate the separation method into a correction mechanism in which particles were detected between the first substrate and the second substrate and separation was subsequently required for cleaning and correction.

[0023] According to a preferred embodiment, a mechanical tool is used as the means for non-chemical processing or as a further means for non-chemical processing. It is particularly preferred if the mechanical tool interacts with the entire substrate, in particular at the bonding interface. A cutting means, such as a blade, is conceivable as a mechanical tool. In particular, the mechanical tool acts on the entire substrate in addition to a force application, wherein the force application emanates from holders to which the first substrate and the second substrate are bonded and acts on the entire substrate. Particularly preferably, the mechanical tool acts on the entire substrate in a direction that runs essentially parallel to the main extension plane.In one conceivable embodiment, the mechanical tool can comprise at least two separating elements, in particular separating blades or separating wires, which mechanically act on the entire substrate from two opposite sides, in particular simultaneously, to separate the first substrate and the second substrate from each other. In particular, it is preferably provided that the tool, in addition to a separating force, acts on the bonding interface, which emanates from the substrate holder system and attempts to pull the first substrate and the second substrate apart.

[0024] In a further preferred embodiment, a solvent is used as the means for chemical processing. In particular, it is provided that a fusion-bonded overall substrate is in a chemical reaction equilibrium. If the reaction equilibrium is shifted according to Le Chatelier's principle by exposing the fusion-bonded overall substrate to a solvent that dissolves the prebond connection in the bonding interface, the equilibrium shifts such that the substrates are separated from one another due to the action of the solvent. The person skilled in the art specifically uses solvents for the overall substrate that shift the reaction equilibrium in the bonding interface, preferably according to Le Chatelier's principle, and thus separate the overall substrate.To accelerate the chemical separation reaction, the non-chemical means, preferably a complementary mechanical tool, is preferably used.

[0025] A possible important chemical reaction of a substrate surface terminated with hydroxyl groups is

[0026] This chemical equilibrium reaction describes the conversion of hydroxyl groups through a condensation reaction to form a silicon-oxygen compound with the elimination of water. The Si atoms each originate from one of the two substrates that make up the overall substrate. The oxygen connects them together.

[0027] Preferably, the solvent is incorporated into the first substrate and / or the second substrate, in particular in such a way that supersaturation is established in the region of the binding interface. The first substrate and / or the second substrate, in particular due to their porous design, is thus designed to serve as a reservoir with which the reaction direction of an equilibrium reaction is influenced.

[0028] The storage takes place after the prebond, but in any case during the heat treatment. The aforementioned activation of at least one of the two substrate surfaces allows the storage of a fluid, particularly water. This water, stored in the reservoir prior to bonding, is required for other physical and chemical effects, which will not be discussed in detail here. It is important to understand that after the water has been used up, the reservoir is largely empty and can be refilled. If, after a fusion bond has been completed in the prebond, it is determined that the two substrates need to be separated again, the entire substrate can be placed in a solvent, particularly water. This water then diffuses not only across the interface, but also via the reservoir to the top or bottom of the interface, i.e.the bond interface, and, according to Le Chatelier's principle, exerts a constraint on the aforementioned chemical equilibrium. Since an excess of water is present, the aforementioned chemical equilibrium reacts to avoid the external constraint, i.e., the excess of water. The chemical equilibrium thus reacts to the left and cleaves the Si-O-Si bond through hydrolysis. It is therefore preferable for a chemical bond to be cleaved through hydrolysis in the region of the bond interface.

[0029] An important aspect is therefore the supersaturation of the interface with a solvent, especially water, via an existing porous reservoir.

[0030] In particular, it is provided that the entire substrate is placed in a solvent bath. It is preferably provided that the entire substrate and the solvent bath are designed such that the bonding interface is located below a solvent surface or below a level of the solvent, respectively, so that the solvent can continuously act on the bonding interface until complete separation between the first substrate and the second substrate occurs. A solvent bath is a particularly energy-saving method for promoting chemically induced separation. In particular, a tank is provided for the solvent bath to provide the solvent.Preferably, it is conceivable that the solvent bath comprises means for promoting the penetration of the solvent into a notch between the first substrate and the second substrate or for promoting the exchange of solvent in the notch between the first substrate and the second substrate. This selectively and preferentially provides unused solvent at the bonding interface to be severed. For example, a means for causing movement of the solvent in the solution bath is conceivable.

[0031] It is particularly preferably provided that the solvent is directed onto the bonding interface by means of a nozzle element. In particular, a solvent jet is directed onto the bonding interface. As a result, the solvent can effectively support chemical separation upon impacting the bonding interface. For example, it is conceivable that particularly advantageous dissolution can be achieved by means of jet pressure. A solvent jet is preferably directed onto a peripheral edge of the entire substrate. It is also conceivable that the bonding interface is acted upon by means of a plurality of nozzle elements, preferably simultaneously. It is also conceivable that the trough in which the solvent is located is constructed to be pressure-stable and that increasing the solvent pressure results in an increased diffusion rate of the solvent into the reservoir.This is especially necessary when the solvent's surface tension makes it very difficult for it to penetrate a reservoir with a relatively small pore size. It is also conceivable to add surfactants to reduce the surface tension and facilitate the solvent's access to the reservoir.

[0032] It is particularly preferred if a first contribution to the separation is made by the means for chemical processing and a second contribution is made by the means for non-chemical processing, wherein the ratio between the first contribution and the second contribution assumes a value between 1:99 and 99:1. The ratios of the contributions of the chemical separation reaction to the proportions of the mechanical separation reaction vary from the ratio of chemical contribution to the mechanical or optical contribution of 1:99 to 99:1. A ratio of 0:100 would be a purely mechanical / optical separation process without the use of a chemical solvent, and a ratio of 100:0 would be a purely chemical separation process. For example, to compare and determine the respective proportions, the respective methods are carried out individually, and a separation duration is then determined. The respective contribution can be estimated based on these durations.

[0033] Furthermore, it is preferably provided that the solvent is exchanged, in particular renewed, after a defined number of times, preferably after each complete separation of the substrates. This advantageously ensures that the next complete separation is provided with the purest possible solvent composition, which effectively initiates separation. For example, the solvent is drained from the tank for this purpose.

[0034] Furthermore, it is preferably provided that the solvent is an aprotic-nonpolar solvent and / or an aprotic-polar solvent and / or a protic solvent. Preferably, the solvent and / or the solvent mixture (a mixture of at least two solvents) are used specifically for the chemical separation reaction of the entire substrate. The solvent or the solvent mixture can contain one or more components from the lists given: • aprotic-nonpolar solvents, in particular alkanes, alkenes, alkynes, aromatics with aliphatic and / or aromatic substituents, esters, in particular of carboxylic acid, ethers, symmetrically constructed molecules, carbon-containing solvents with their sulfides and / or oxides, halogenated hydrocarbons, in particular perfluorinated hydrocarbons, and / or

[0035] • aprotic-polar solvents, in particular ketones, lactones, lactams, nitriles, nitro compounds, tertiary carboxylic acid amides, urea derivatives, sulfoxides, sulfones, carbonic acid esters and / or

[0036] • contain protic solvents, in particular water, short-chain alcohols, primary and secondary amines, carboxylic acids, primary and secondary amides, mineral acids, and / or

[0037] 1,1,1-trichloroethane, 1,2-dichloroethane (ethylene dichloride), 1,4-dioxane, 1-butanol, 1-butanol,

[0038] 1-Decanol, 1-Octanol, 1-Pentanol (amyl alcohol), 1-Propanol, 2-Butanol, 2-Ethyl-1 -butanol,

[0039] 2-Ethylhexanol, 2-Methyl-1-propanol, 2-Methyl-2-propanol (tert-Butanol), 2-Octanol, 2- Propanol, 2-Propanol (Isopropylalkohol), 3-Methyl-1 -butanol (Isoamylalkohol), 4-Methyl-2- pentanol (MIBC), Aceton, Acetonitril, Anilin, Anisol, Benzol, Benzonitril, Benzylalkohol, Brombenzol, Chinolin, Chlorbenzol, Chloroform, Cyclohexan, Cyclohexanol, DCM), Diacetonalkohol, Dibutylether, Diethylenglycol, Diethylether, Dimethylacetamid, Dimethylformamid, Dimethylsulfoxid, Eisessig, Essigsäureanhydrid, Essigsäureethylester, Ethanol, Ethanol, Ethylenglycol, Ethylenglycoldimethylether, Formamid, Hexanol, Methanol, Methanol, Methylenchlorid (Dichlormethan,, M ethylethyl keton (Butanon), n-Heptan, n-Hexan, Nitrobenzol, Nitromethan, N-Methyl-2-pyrrolidon (NMP), N-Methylformamid, n-Pentan, Petro- lether / Leichtbenzin, Piperidin, Propanol, Propylencarbonat (4-Methyl-1 ,3-dioxol-2-on), Pyridin, Schwefelkohlenstoff, Sulfolan, tert-Amylalkohol, tert-Butanol, tert-Butylmethylether (MTBE), Tetrachlorethen,Carbon tetrachloride, tetrahydrofuran, tetrahydrofurfuryl alcohol, toluene, trichloroethylene, triethylamine, triethylene glycol, triethylene glycol dimethyl ether (triglyme), water, γ-butyrolactone. It is particularly preferred that a solvent mixture be used to ensure the most optimal dissolution of the binding interface.

[0040] The specific solvent used depends on the material system to be separated. Ultrapure distilled water has proven advantageous for breaking silicon oxide-silicon oxide bonds or silicon-silicon oxide bonds, as it allows the bonds between the substrate surfaces (Si-O-Si bonds) to be severed, and the substrate surfaces are then terminated again with OH groups. At this stage, the interaction between the substrates again occurs via van der Waals forces, which are known to be much weaker than the forces of the prebond. Thus, the substrates of the overall substrate can be separated from each other chemically and mechanically more effectively than with mechanical separation.

[0041] Furthermore, it is preferably provided that after separation, the first substrate and / or the second substrate is cleaned by means of a cleaning device and / or dried by means of a drying device. This advantageously makes it possible to free the separated first and second substrates from contaminants that remain as particles or residues after separation. In this case, cleaning is particularly preferably carried out with distilled water or DI water, and drying is carried out in such a way that a particle-free provision of surfaces of the separated first substrate and second substrate is possible. The first substrate and the second substrate can then be joined to one another, for example.

[0042] In particular, it is provided that a solvent supply is adjusted by means of a dosing device. This advantageously makes it possible to adjust the solvent supply, in particular its dosage and / or concentration, in a targeted manner, preferably depending on the type and / or properties of the binding interface. It is conceivable that a dosage and / or solvent concentration changes during the separation treatment. This preferably allows the separation measures to be further optimized and, in particular, further adapted to the respective requirements.

[0043] It is particularly preferably provided that a separating force is exerted on the first substrate and on the second substrate, wherein the separating force acts substantially perpendicular to a main extension plane of the first and / or second substrate. In other words: the separating force attempts to separate the first substrate and the second substrate from one another, in particular to pull them apart. In particular, shear forces are avoided which would otherwise or possibly act on the first substrate and the second substrate from holding devices for fixing the entire substrate to the first substrate and the second substrate, as long as the first substrate and the second substrate are still connected to one another via the bonding interface. In this way, the abrasive effect of particles in the bonding interface on the substrate surfaces of the first substrate and the second substrate is preferably avoided.For example, it is provided that the first substrate is fastened in a first substrate holder and the second substrate is fastened in a second substrate holder, wherein during separation, in addition to the action of the means for chemical processing, the tool of the first substrate holder and the second substrate holder are also moved apart.

[0044] A first exemplary embodiment of a method according to the invention comprises the following steps, in particular carried out consecutively and / or simultaneously, in particular with the following sequence:

[0045] In preparation for the method for separating bonded substrates, the entire substrate is loaded into the device for separating bonded substrates. In a first method step, the entire substrate is secured on a substrate holder, in particular a first substrate holder. In various embodiments of the method, this securing can be achieved using vacuum fixation and / or, preferably, mechanical fixation. In a second method step, the entire substrate secured on one substrate holder is attached to a second substrate holder, in particular, an upper substrate holder. This securing can be achieved using vacuum fixation and / or, preferably, mechanical fixation.

[0046] In a third process step, the separation of the entire substrate is initiated by inserting a separating element, preferably a mechanical tool, in particular a blade, between the first substrate and the second substrate of the entire substrate, along the original bonding interface. Alternatively, clamping rings at the respective substrate edges of the first substrate and the second substrate can exert a force perpendicular to the bonding interface into the entire substrate.

[0047] In a fourth process step, a solvent is introduced into the bonding interface to break the chemical bonds. A tray of the device is filled with the solvent to above the level of the bonding interface. The solvent gradually penetrates the breaking interface, the bonding interface and / or an existing reservoir, and separates the first and second substrates. Alternatively to the fourth process step, the entire substrate can be immersed in a tray already filled with solvent.

[0048] This merely represents a kinematic reversal for the process. In a fifth process step, after this initial opening of the bonding interface of the entire substrate and exposure to solvent, the substrates are additionally mechanically clamped. Preferably, they are clamped particularly on the side where the mechanical tool penetrates the bonding interface by applying a vertical tensile force that pulls the first and second substrates apart in a wedge shape. This causes solvent to continue to flow into the bonding interface, where the mechanical and chemical separation of the entire substrate takes place.

[0049] In a sixth process step, as the separation process progresses, in addition to the wedge-shaped separation of the substrates, they are also pulled apart vertically by gradually, in particular stepwise, moving the first and second substrate holders, with the substrates mounted thereon, away from each other. In a seventh process step, the substrates are completely separated from each other. In an eighth process step, the substrates are cleaned, dried, and transported and deposited by means of a transport device into the storage device, in particular substrate boxes.

[0050] A second exemplary embodiment of a method according to the present invention comprises the following steps, in particular carried out consecutively and / or simultaneously, in particular with the following sequence:

[0051] In preparation for the bonded whole substrate dicing process, the whole substrate is loaded into the bonded whole substrate dicing device.

[0052] In a first method step, the entire substrate is placed on a first substrate holder, in particular the lower substrate holder, and secured. In various embodiments of the method, the securing or securing can be achieved with vacuum fixation and / or, preferably, with mechanical fixation. In a second method step, the entire substrate secured on one substrate holder is secured to a second substrate holder, in particular the upper substrate holder. The securing or securing can be achieved with vacuum fixation and / or, preferably, with mechanical fixation.

[0053] In a third process step, the separation of the entire substrate is initiated by introducing solvent into the bonding layer of the entire substrate from at least one nozzle element, in particular at comparatively high pressure, in particular at 0.1 bar overpressure, preferably at 0.5 bar overpressure, more preferably at 1 bar overpressure, most preferably at 2 bar overpressure, and optimally at 5 bar overpressure. The solvent thus gradually penetrates the breaking bond interface and separates the substrates from one another. The positioning of the solvent jet in the separation plane and the timing and dosing duration play at least as important a role for the successful separation of the substrate stack as the pressure of the solvent jet.

[0054] The escaping solvent is collected in a drip tray of the separation device. When using a few milliliters of solvent, in particular, the tray can be dispensed with entirely. In a fourth process step, after this initial opening of the bonding interface of the entire substrate and exposure to solvent, the first substrate and the second substrate are additionally mechanically clamped. Preferably, they are clamped, particularly on the side where the solvent penetrates the bonding interface from the nozzle element, by applying a vertical tensile force that pulls the first and second substrates apart in a wedge shape. This causes solvent to continue flowing into the bonding interface, and the mechanical and chemical separation of the entire substrate occurs.

[0055] In a fifth process step, as the separation process or severing progresses, in addition to being pulled apart in a wedge shape, the substrates are also pulled apart vertically, in particular stepwise, by the first and second substrate holders, each with the first and second substrates mounted thereon, moving away from each other. In a sixth process step, the substrates are completely separated from each other. In a seventh process step, the substrates are cleaned, dried, and transported and deposited by means of a transport device into the storage device, in particular substrate boxes.

[0056] A third exemplary embodiment of a method according to the present invention comprises the following steps, in particular carried out consecutively and / or simultaneously, in particular with the following sequence:

[0057] In preparation for the process for separating bonded substrates, the entire substrate is loaded into the device for separating bonded substrates. In a first process step, the entire substrate is secured on a first substrate holder, in particular a lower substrate holder. In various embodiments of the process, the securing can be achieved with vacuum fixation and / or preferably with mechanical fixation. In a second process step, the entire substrate secured on one substrate holder is attached to a second substrate holder, in particular an upper substrate holder. The securing can be achieved with vacuum fixation and / or preferably with mechanical fixation.

[0058] In a third process step, the separation of the entire substrate is initiated by inserting the release agent or mechanical tool, in particular a blade, between the substrates of the entire substrate along the original bonding interface. In a fourth process step, particularly simultaneously with the third process step, solvent is introduced from a nozzle element, particularly at high pressure, into the bonding interface at the blade. This way, the release agent and the substrate are lubricated with the solvent, allowing the separation to proceed with less damage to the substrate.

[0059] As an alternative to introducing the solvent into the mechanically strained bonding interface at high pressure, a defined volume of solvent, in particular a few milliliters, in particular a drop of solvent, can be introduced into the bonding interface at low pressure so that the capillary forces and / or surface tensions draw the solvent into the bonding interface.

[0060] Alternatively, clamping rings at the respective substrate edge can exert a force perpendicular to the bonding interface into the entire substrate. This allows the solvent to gradually penetrate the breaking bond interface and separate the substrates.

[0061] In a fifth process step, after this initial opening of the bonding interface of the entire substrate by means of the blade and exposure of the bonding interface to solvent, the substrates are additionally mechanically clamped. Preferably, they are clamped particularly on the side on which the blade penetrates the bonding interface by applying a vertical tensile force that pulls the substrates apart in a wedge shape. This causes solvent to continue to flow, opening the bonding interface and mechanically and chemically separating the entire substrate. In a sixth process step, as the separation process progresses, in addition to the wedge-shaped pulling apart of the substrates, they are also pulled apart vertically by gradually, in particular stepwise, moving the first and second substrate holders, with the substrates attached to them, away from each other.In a seventh process step, the substrates are completely separated from each other. In an eighth process step, the blade is preferentially retracted to an initial position.

[0062] In a ninth process step, the substrates are cleaned, dried and transported and placed into the storage device, in particular substrate boxes, by means of a transport device.

[0063] Preferably, processes in the device according to the invention are carried out automatically. Automation requires measurement and control systems as well as computer-aided process steps. For this purpose, processes can be created, stored, and executed as recipes. Recipes are optimized collections of values ​​for parameters that are functionally or process-related. The use of recipes allows the reproducibility of production processes to be ensured.

[0064] According to a further aspect of the present invention, a device for carrying out a method according to the invention is provided, i.e., a device for separating the first substrate and the second substrate from one another or for separating an entire substrate, wherein the device comprises a means for non-chemical processing and a means for chemical processing. All advantages and properties described for the method can be applied analogously to the device, and vice versa. In the following, the device is also referred to as a separating device.

[0065] Preferably, the means for non-chemical processing and the means for chemical processing are integrated into a tool component. This makes it particularly easy to process the same location in the bonding interface simultaneously with the tool component. An exemplary device for separating preferably fusion-bonded substrates can include at least one of the following functional units, whereby several similar units and / or functionally integrated units in one device can be advantageous according to the invention:

[0066] -Alignment device for reproducibly placing the entire substrate to be separated in a receiving device, and

[0067] -Receiving device for receiving a complete substrate to be separated in a receiving device, and

[0068] -Separation device with combined mechanical or optical means or means for accelerating particles and means for providing chemical agents, with holding devices, in particular a first substrate holder and / or a second substrate holder, dosing device for solvents, with moving devices for the separation device and in particular for the separated substrates, and -Cleaning device, in particular with DI water for removing the particles from the substrate surface and / or generating OH bonds for renewed fusion bonding, and

[0069] -Drying device for drying the cleaned substrates particle-free, and -Transport device for the first and / or second substrates and / or the entire substrate, and

[0070] -Storage device for total substrate and / or for separate substrates, and

[0071] - Media supply modules, particle reduction device, substrate identification reading device. An exemplary device can advantageously be constructed in a modular design. A further development of the device for separating entire substrates can be part of a complex fusion bonding device with measurement and reprocessing.

[0072] In particular, mechanical alignment devices, for example with notch detection and electronic-mechanical sensors, can be used for the alignment device, so that substrates, ie first substrate, second substrate and / or entire substrate, can be gently fixed in position.

[0073] In another particularly advantageous embodiment of the device, an alignment device can comprise image capture means, in particular at least one camera system for overall substrate and / or substrate detection and / or substrate edge detection with corresponding control and computer-based data evaluation. In a preferred device for separating entire substrates, the entire substrate, which has been assembled in particular from a first product substrate and a second product substrate, is held in a receiving device on a substrate holder.

[0074] Substrate holders can be

[0075] -mechanical fixations, in particular clamps and / or

[0076] - Vacuum fixations, in particular with individually controllable vacuum tracks or interconnected vacuum tracks and / or

[0077] - electrical fixations, in particular electrostatic fixations and / or

[0078] - magnetic fixations and / or

[0079] - Adhesive fixations, in particular with gel pads or fixations with adhesive, in particular controllable, surfaces. The fixations can be controlled electronically. For example, devices for separating entire substrates have proven particularly advantageous.

[0080] A first embodiment of a separation device or a device for carrying out a method according to the invention with combined means for chemical and non-chemical processing comprises a tank for chemically treating the entire substrate to be separated with the solvent. The substrate holding device and the alignment device are integrated into the separation device, so that an entire substrate can be placed on loading pins, in particular in an automated manner, and secured in an appropriately aligned manner on the substrate holding device.

[0081] The separation device is fluidically connected to a media supply and a media outlet so that solvents can be metered into the tank. The metered amount of solvent varies depending on the design. However, it is generally true that the solvent level must be above the level of the bonding interface of the entire substrate in order to carry out the chemical separation. The media outlet removes the used and, in some cases, consumed solvent from the tank, particularly after each separation of the entire substrate. It has proven particularly advantageous if the tank can be cleaned, particularly automatically, between separation processes. For cleaning, the tank can advantageously be rinsed with, in particular, DI water from cleaning nozzles connected to the supply modules. The separation device can include a cutting blade for mechanically separating the entire substrate.

[0082] In another embodiment of the separating device, it can comprise at least two separating blades which mechanically separate the entire substrate from two opposite sides, in particular simultaneously.

[0083] In a further embodiment of the separating device, it may include at least one separating blade and at least one fluid nozzle that can be aligned with the bonding interface of the entire substrate.

[0084] In a further embodiment of the separating device, it can include an integrated separating blade with at least one nozzle element or a fluid nozzle. In the integrated separating blade with a fluid nozzle, the fluid nozzle is functionally and materially connected to the separating blade, so that the separating blade can be moved with the integrated nozzle using a movement device and / or positioning device. Thus, the separating device requires exactly one integrated positioning device for the nozzle element and for the separating blade.

[0085] In one conceivable embodiment of the separation device, it does not comprise a mechanical separating blade, but merely at least one nozzle for the purely chemical separation of the entire substrate. Designed particularly as a slit nozzle or fan nozzle, the separation device can specifically direct the solvent, particularly at high pressure, into the immediate vicinity of the bonding layer, so that the entire substrate is separated. In particular, a clamping and lifting device can perform the mechanical separation of the entire substrate at the same time.

[0086] In an alternative embodiment of the separation device, the substrate is immersed in the solvent at least up to the bonding interface to be separated, and additional solvent is directed into the bonding interface using at least one nozzle at high pressure to initiate the separation of the entire substrate. In particular, the clamping and lifting device can carry out the mechanical separation of the entire substrate at the same time. All embodiments of the separation device can include at least one mechanical clamping and lifting device. The clamping and lifting device serves to hold the first substrate, in particular at the substrate edge and / or on the back, and to release the entire substrate with a normal separation force as a reinforcement of the effect of the separation blade and the solvent, and in particular to lift the upper substrate from the lower substrate without transverse movement.

[0087] The advantage of the normal lifting of the first substrate from the second substrate is that in the case of structured substrates, the structures are not sheared during the separation process, which is an undesirable force stress for the structures.

[0088] Thus, according to the invention, in particular the entire substrate made up of structured substrates and / or substrates with through-hole plating and / or so-called hybrid bonds can be gently separated from one another and, in further process steps, corrected and bonded together again.

[0089] A further embodiment of the clamping and lifting device of the separating device can, in particular, clamp the upper substrate completely at the edge section where the separating blade was used, and then lift it off. An alternative embodiment of the clamping and lifting device of the separating device can, in particular, clamp the upper substrate in approximately 180-degree sections with two jaws and lift it accordingly. Particularly advantageous is the possibility of increasing the lifting with an additional vacuum device, which acts across the entire surface of the substrate to be separated. An alternative embodiment of the clamping and lifting device of the separating device can, in particular, clamp the upper substrate in approximately 90-degree sections with four jaws or in approximately 120-degree sections with three jaws and lift it accordingly. It is possible to increase the number of discrete clamping jaws so that the effect of complete clamping can be achieved.The angle specifications correspond to the technical, in particular special machine construction, non-tolerated values ​​according to ISO 22081. The second and / or first substrate can remain clamped in particular mechanically on the first and / or second substrate holder of the substrate holding device.

[0090] The exemplary device for separating entire substrates can preferably include at least one separation device. The separation device includes the dosing device for the solvent, so that each entire substrate to be separated is treated with freshly formulated and / or freshly purified solvent. This prevents cross-contamination between the substrates.

[0091] When using water, especially DI water as a solvent, the solvent can be filtered, purified and reused in the circuit to separate the total substrate.

[0092] In particularly preferred embodiments, the dosing device for the solvent of the separation device can be designed as at least one alignable and / or movable nozzle element, with which the bonding interface of the entire substrate to be separated can be treated with solvent at overpressure, so that the chemical separation reaction can proceed at an increased reaction rate. The volume of solvent for the separation of an entire substrate is less than 50 ml, preferably less than 5 ml, more preferably less than 1 ml, most preferably less than 0.1 ml, and optimally less than 0.01 ml. Fan nozzles or slit nozzles, which apply a linear force to the bonding interface, are particularly advantageous.This results in a more gentle separation than with the use of nozzles, which emit the solvent like a coherent jet and act on the bonding interface over a small area like a point.

[0093] In a further embodiment of the dosing device according to the invention for the solvent of the separating device, the movable nozzle element and the separating blade form an integrated unit, so that separate alignment and movement of the dosing device can be eliminated. This embodiment is advantageous for dosing, in particular for a single drop of solvent for separating the entire substrate, which is mechanically separated, in particular simultaneously, with the blade.

[0094] The exemplary device for separating entire substrates can preferably include a cleaning device. The cleaning device, in particular using DI water, removes any particles from the substrate surface after the separation of the entire substrate and / or uses DI water to create OH bonds on plasma-treated substrate surfaces for subsequent fusion bonding. The exemplary device for separating entire substrates can preferably include a transport device for substrates and / or the entire substrate. The transport device for substrates and / or the entire substrate can, in particular, be at least one robot with at least one end effector, which comprises a part of the device for separating entire substrates, in particular according to the present invention.To reduce the cycle time of the device, transport devices with at least two specialized end effectors have proven advantageous: at least one end effector can transport at least one complete substrate, and at least one end effector can transport at least one separate substrate. It is advantageous for reducing the cycle time of the device for separating complete substrates if at least one end effector of the transport device is specialized for transporting the complete substrate, and two end effectors can, in particular, simultaneously receive and transport at least two separate substrates.

[0095] The exemplary device for separating entire substrates can preferably include a drying device. The drying device enables the cleaned substrates to be dried particle-free, in particular by utilizing the Marangoni effect. For this purpose, the separated substrates can at least be brought into contact with dry gas or with other solvents. Further drying options in the possible embodiments of the invention can also include centrifugal devices and / or hot plates.

[0096] The exemplary device for separating entire substrates can preferably include a storage device for substrates and / or the entire substrate. The storage device for the entire substrate and / or for separated substrates includes, in particular, both the receiving and handling device and the transfer device for the transport device, as well as optionally intermediate storage and heating devices in the form of heating plates.

[0097] The storage device is particularly flexibly designed for at least two common substrate sizes (especially wafer sizes), so that 200 mm wafers and 300 mm wafers can be stored, transported, and separated without adapting the device. Particularly advantageously, the device for separating entire substrates is convertible for any substrate shape and substrate size. The first substrate, the second substrate, and / or the entire substrate, i.e., the substrates, can have any desired shape, but are preferably circular. The diameter of the substrates is, in particular, industrially standardized. The industry-standard diameters for wafers are 1 inch, 2 inches, 3 inches, 4 inches, 5 inches, 6 inches, 8 inches, 12 inches, and 18 inches.

[0098] The device's embodiments can, in principle, handle any substrate, regardless of its diameter. Square substrates, also called panels, are subsumed as substrates.

[0099] The exemplary device for separating entire substrates can preferably advantageously be constructed in a modular design. Modules are to be understood as functional units of the device, which in particular have standardized sizes and are connected in the device via standardized interfaces. This enables cost-effective conversion and adaptation of the device according to the invention if empty module spaces in the device are expanded and / or newly occupied with individual modules. A further development of the device according to the invention for separating entire substrates can be part of a complex fusion bonding device with measurement of the alignment and / or edge defects and reprocessing.

[0100] Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments and from the drawings.

[0101] They show in:

[0102] Fig. 1 schematically shows an implementation of a method step according to a first exemplary embodiment of the present invention.

[0103] Fig. 2 schematically shows an implementation of a method step according to a second exemplary embodiment of the present invention and

[0104] Fig. 3 schematically shows an implementation of a method step according to a third exemplary embodiment of the present invention.

[0105] In the figures, identical components or components with the same function are identified by the same reference numerals. Figure 1 schematically shows an implementation of a method step according to a first exemplary embodiment of the present invention, carried out using an exemplary device according to the present invention, which is represented as a schematic structural sketch.

[0106] Such a device 7 for separating an entire substrate 3 into a first substrate 13 and a second substrate 23 comprises a first, in particular lower, substrate holder 1 and a second, in particular upper, substrate holder 2. The entire substrate 3 to be separated is fastened to the first substrate holder 1 with mechanical clamps 4. Preferably, the second substrate 23 of the entire substrate 3 can be additionally fastened to the upper substrate holder 2 with further mechanical clamps 4. The first substrate holder 1 with the mechanical clamps 4 and with the entire substrate 3 to be separated is located in a tank 5 for the chemical separation of the entire substrate 3. For this purpose, liquid solvent 6 is fed into the tank 5 via a bonding interface, which forms a planned separation plane, so that the solvent 6 penetrates the bonding interface and can separate the entire substrate 3 into the first substrate 13 and the second substrate 23.

[0107] Figure 2 schematically shows an implementation of a method step according to a second exemplary embodiment of the present invention, which is represented as a schematic structural sketch.

[0108] The device 7 for separating the entire substrate 3 also comprises a first, in particular lower, substrate holder 1 and a second, in particular upper, substrate holder 2. The entire substrate 3 to be separated is fastened to the first substrate holder 1 with mechanical clamps 4. Preferably, the second substrate 23 of the entire substrate 3 can be additionally fastened to the second substrate holder 2 with further mechanical clamps 4. The first substrate holder 1 with the mechanical clamps 4 and with the entire substrate 3 to be separated is located in the tank 5 for chemical separation of the entire substrate 3. In the method step shown, the entire substrate 3 is separated with a nozzle element 8, in particular with a nozzle that directs solvent 6 into the bonding interface. The solvent 6 penetrates the bonding interface and enables the separation of the entire substrate 3 along the separation plane or the bonding interface.Figure 3 schematically shows an implementation of a method step according to a third exemplary embodiment of the present invention, which is represented as a schematic structural sketch.

[0109] The device 7 for separating entire substrates 3 includes a first, in particular lower, substrate holder 1 and a second, in particular upper, substrate holder 2. The entire substrate 3 to be separated is fastened to the first substrate holder 1 with mechanical clamps 4. Preferably, the second substrate 23 of the entire substrate 3 can be additionally fastened to the upper substrate holder 2 with further mechanical clamps 4. The first substrate holder 1 with the mechanical clamps 4 and with the entire substrate 3 to be separated is located in a trough 5 for the chemical separation of the entire substrate 3, in particular for collecting the liquid solvent (not shown), which promotes the separation of the entire substrate 3. In the method step shown, the entire substrate 3 is separated with a mechanical tool 9, in particular with a wedge, which is guided into the bonding interface.To accelerate the separation of the entire substrate 3, the liquid solvent (not shown) can be directed into the tank 5 above the bonding interface to lubricate the mechanical tool 9. The solvent penetrates the bonding interface and enables the separation of the entire substrate 3.

[0110] List of reference symbols:

[0111] 1 first substrate holder

[0112] 2 second substrate holder

[0113] 3 Total substrate

[0114] 4 terminal

[0115] 5 tub

[0116] 6 Solvents

[0117] 7 Device

[0118] 8 nozzle element

[0119] 9 Tools

[0120] 13 first substrate

[0121] 23 second substrate

Claims

Claims 1 . A method for separating a complete substrate (3) into a first substrate (13) and a second substrate (23), wherein the first substrate (13) and / or the second substrate (23) is intended as a component of an electronic component, comprising: Providing the overall substrate (3) comprising the first substrate (13) and the second substrate (23), wherein the first substrate (13) and the second substrate (23) are connected to one another via a generated connection along a bonding interface, and - separating the entire substrate (3) into the first substrate (13) and the second substrate (23) along the bonding interface, wherein a means for chemical processing and preferably a means for non-chemical processing is used to separate the entire substrate (3) into the first substrate (13) and the second substrate (23).

2. Method according to claim 1, wherein the entire substrate (3) is held together essentially by means of van der Waals' forces, in particular is a prebond, and preferably the connection produced is a connection produced by a fusion bond.

3. Method according to one of the preceding claims, wherein the first substrate (13) and the second substrate (23) are pulled apart in response to the means for non-chemical processing, in particular in a wedge shape.

4. Method according to one of the preceding claims, wherein a substrate holder system with a first substrate holder (13) and a second substrate holder (23) is used as the means for non-chemical processing, wherein the first substrate (13) is fastened in a first substrate holder (1) and the second substrate (23) is fastened in a second substrate holder (23), wherein during the separation, in addition to the action by the means for chemical processing, the first substrate holder (1) and the second substrate holder (2) are moved apart.

5. Method according to one of the preceding claims, wherein a separating force is applied to the first substrate (13) and to the second substrate (23), wherein the separating force acts substantially perpendicular to a main extension plane of the first substrate (13) and / or the second substrate (23).

6. Method according to one of the preceding claims, wherein a mechanical tool (9) is used as the means for non-chemical processing or as a further means for non-chemical processing.

7. Method according to one of the preceding claims, wherein a solvent (6) for shifting a reaction equilibrium, preferably according to the principle of Le Chatelier, is used as the means for chemical processing.

8. The method according to claim 7, wherein the solvent (1) is incorporated in the first substrate (13) and / or second substrate (23) to form a reservoir, in particular such that supersaturation is established in the region of the binding interface.

9. The method according to any one of claims 7 or 8, wherein a chemical compound is cleaved in the region of the binding interface by hydrolysis.

10. The method according to claim 6 or 7, wherein the solvent (6) is directed onto the binding interface by means of a nozzle element (8).

11. Method according to one of the preceding claims, wherein after the separation, the first substrate (13) and / or the second substrate (23) is cleaned by means of a cleaning device and / or dried by means of a drying device.

12. Method according to one of the preceding claims, wherein a solvent supply is adjusted by means of a metering device.

13. Device (7) for carrying out a method according to one of the preceding claims, wherein the device (7) comprises a means for non-chemical Processing and a device for providing a means for chemical processing.

14. Device (7) according to claim 13, wherein the means for non-chemical processing and the means for chemical processing are integrated into a common tool component.

15. Device (7) according to claim 13 or 14, wherein the device (7) comprises a first substrate holder (1) for fixing to the first substrate (13) and a second substrate holder (2) for fixing to the second substrate (23), wherein a Distance between the first substrate holder (1) and the second substrate holder (2) is variable.

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