Method for producing nanosheet or microsheet element by means of patterned carrier layer

Abstract

The present invention provides a method for preparing a nano-sheet or micro-sheet element based on a laminate (14), the nano-sheet or micro-sheet being made of graphene and / or other sheet-like material. The laminate (14) comprises a growth substrate (1), a nano-sheet or micro-sheet layer (2) and a carrier layer (3). The nanosheet or microsheet layer (2) is adapted to form the nanosheet element or microsheet element. The method comprises at least a step of electrochemical delamination of the laminate (14) by electrolysis such that the growth substrate (1) is separated from the nano-or micro-sheet layer (2) and the carrier layer (3). The electrochemical delamination step of the laminate (14) is carried out by means of a carrier layer (3) having a pattern (31) with a plurality of local depressions (311) and / or elevations (312).

Description

Technical Field

[0001] The present invention relates to a method for preparing a nanosheet element or a microsheet element, which is specifically made of graphene and / or other sheet materials (such as metal films, nanostructures, and isolation films).

[0002] According to the Marie Sklodowska-Curie grant agreement No. 101025295, the project involved in this application has received funding from the Horizon 2020 research and innovation program of the European Union. Background Art

[0003] Graphene is a material formed by only a single layer of carbon atoms, and these carbon atoms are interconnected by covalent bonds in a hexagonal repeating pattern. Especially due to its high mechanical strength, excellent thermal conductivity and electrical conductivity, as well as many other excellent properties, graphene is increasingly widely used in electronic devices such as biosensors, transistors, and integrated circuits (such as CMOS-based microchips). The application fields of such graphene devices include, for example, consumer electronics, medical technology, automotive engineering, optics, telecommunications, batteries, aerospace technology, and so on.

[0004] The application and utilization of graphene and graphene layered materials have become the subject of a large amount of academic research and development. Significant progress has been made in this field recently. However, the industrial production and commercial application of using graphene and / or other types of thin sheet materials have progressed slowly and face many challenges. The main reason for the slow application transformation is that there are many challenges in the process of transferring such thin sheet materials from their growth substrates to the target substrates.

[0005] In the conventional production process, the thin sheet material is synthesized on a growth substrate made of metal by chemical vapor deposition. Currently, the mainstream method for transferring the thin sheet material from the growth substrate to the target device is by etching the growth substrate. For example, EP 2679540A1, EP 2937313A1, EP 3135631A1, and US 2017 / 0365477A1 disclose methods for manufacturing graphene-based transistors using metal substrate etching technology. The method of etching the growth substrate has defects, because it will cause i) polymer contamination of the thin sheet material, ii) dissolution and thus loss of the growth substrate, iii) affect the reproducibility of the process, and iv) generate toxic chemical by-products. In addition, the etching process is time-consuming, which means that it takes 3 to 4 hours to etch a copper foil with a thickness of about 25 pm (an area of about 4 cm 2 ) using a 50 mM ammonium persulfate-based copper etchant. These factors seriously affect the electronic performance of the final device and significantly affect the attractiveness of its commercial development.

[0006] A feasible but in-practice inapplicable method for separating thin-film materials from a growth substrate is physical exfoliation. However, in the case of a small film thickness, physical exfoliation is not feasible because it may cause damage to the sample and the film will adhere to its growth substrate. US2020 / 0387073A1 discloses a delamination method based on physical delamination of each layer combined with the water penetration effect.

[0007] Another method is to use an electrochemical process of electrolysis to achieve rapid separation of thin-film materials from their growth substrates. The electrolytic cell used in the electrochemical process usually includes an anode, a cathode, and an electrolyte reagent (i.e., electrolyte solution). The cathode of the electrolytic cell can be composed of, for example, a thin-film material disposed on the growth substrate. The electrolysis process is initiated by applying a direct current voltage to the electrolytic cell. Electrolyte reagents such as sodium hydroxide, sodium persulfate, sodium chloride, or potassium persulfate can be used in this process. During this process, protons can diffuse through the thin-film material or penetrate from the side to form hydrogen bubbles at the interface between the growth substrate and the thin-film material of the electrolytic cell, thereby generating a delamination effect that prompts the separation of the thin-film material from its growth substrate. Electrochemical delamination through the electrolysis process is a feasible technique that can rapidly separate the thin-film material film from its growth substrate within just a few minutes. Therefore, separating thin-film materials from the growth substrate by electrolysis is an ultra-rapid technique for transferring two-dimensional thin materials from their growth substrates to target devices. For example, WO 2022 / 096640 A1, US2015 / 068684A1, CN 110581063 A, and CN111232964A disclose methods for electrochemical delamination through electrolysis. Other prior art documents that disclose graphene electrochemical transfer methods include US2020 / 0235212A1, US2014 / 0238873 A1, US2017 / 0361599 A1, and US2014 / 0130972 A1.

[0008] In order to transfer nanosheets or microsheets (i.e., thin-film materials or films) to a target substrate, certain structural stability must be imparted to the nanosheets or microsheets, which is usually achieved by attaching a carrier layer. The carrier layer is used for transfer and is removed after the nanosheets or microsheets are attached to the target substrate. Summary of the Invention

[0009] The object of the present invention is to provide a method that can prepare nano- or micro-sheet elements with high quality and high efficiency, thereby enabling large-scale industrial production.

[0010] This object is achieved by the method described in claim 1. More embodiments of this method are provided in the dependent claims.

[0011] Accordingly, the present invention provides a method for preparing a nano-sheet element or a micro-sheet element based on a laminate, the nano-sheet element or the micro-sheet element being made of graphene and / or other sheet materials (such as metal films, nanostructures, and isolation films), the laminate including a growth substrate, a nano- or micro-sheet layer, and a carrier layer, and adjusting the nano- or micro-sheet layer to form the nano-sheet element or the micro-sheet element.

[0012] Wherein, the method at least includes an electrochemical delamination step of the laminate by electrolysis, such that the growth substrate is separated from the nano- or micro-sheet layer and the carrier layer.

[0013] The electrochemical delamination step of the laminate by electrolysis is carried out through the carrier layer, and the carrier layer has a pattern, and the pattern has a plurality of local depressions and / or protrusions.

[0014] There are various reasons for using a patterned carrier layer. For example, the patterning of the carrier layer can be used as a marker for correctly positioning the nano- or micro-sheet layer on a target substrate, and / or for aligning the nano- or micro-sheet layer with certain functional features of the target substrate. In some embodiments, the pattern is in the form of through-going apertures that are also provided in the nano- or micro-sheet layer, and which may be required for specific functions of the nano- or micro-sheet layer in a target device. The through-holes may also exist in the nano- or micro-sheet layer to separate multiple nano-sheet elements or micro-sheet elements provided on the nano- or micro-sheet layer. Only one of these nano-sheet elements or micro-sheet elements may be used for a single target device. Therefore, the pattern in the form of through-holes or non-through-holes may have a perforating function. Accordingly, by providing a pattern in the form of through-holes, independent portions of the nano- or micro-sheet layer can be allocated to each of a plurality of target devices, and / or to each of a plurality of functional components of a single target device. In this case, when there are electrical contacts on the target device to be in contact with the nano-sheet element or the micro-sheet element, the nano- or micro-sheet layer can be patterned so as to correctly connect these contacts. Thereafter, the pattern of the carrier layer can be used as a marker for correctly positioning the nano- or micro-sheet layer on the contacts of the target substrate.

[0015] By using a pre-patterned carrier layer in the electrochemical delamination step instead of patterning the carrier layer after delamination, the production process can be significantly simplified and accelerated.

[0016] Therefore, the carrier layer is pre-patterned before the electrochemical delamination step. Combining the pre-patterned carrier layer with electrolysis-based delamination enables the rapid production of a large number of high-quality nanosheet or microsheet components. The pre-patterning of the carrier layer is typically carried out when the carrier layer is attached to the growth substrate by the nanosheet layer or microsheet layer, which significantly simplifies the device processing compared to the post-patterning process of the carrier layer implemented after removing the carrier layer from the growth substrate. In addition, if the carrier layer can be patterned when it is still attached to the growth substrate or even before that, the time for transferring the nanosheet layer or microsheet layer from the growth substrate to the target substrate can be greatly saved. If the nanosheet layer or microsheet layer attached to the growth substrate is adjusted to form a plurality of nanosheet or microsheet components, the advantage of patterning the carrier layer before electrochemical delamination is particularly significant.

[0017] Electrochemical delamination by electrolysis combined with pre-patterning of the carrier layer has significant advantages because the delamination process is generally not affected by the pattern of the carrier layer. In this case, local thinning or even absence of the carrier layer caused by the pattern usually does not have any impact on the delamination process. Other methods (such as growth substrate etching or physical peeling) not only significantly increase the time consumption, but also may cause problems due to local thinning of the carrier layer caused by the pattern. In addition, due to electrolysis, the growth substrate does not dissolve and can be reused multiple times. Moreover, encapsulating a plurality of nanosheet layers or microsheet layers by the electrochemical delamination step can avoid the risk of contaminating these layers with performance-degrading materials (such as polymers).

[0018] In this article, the nanosheet component or microsheet component is regarded as a finished component that is a part of the target device or suitable to be a part of it. In contrast, the nanosheet layer or microsheet layer refers to the material used to prepare one or more such nanosheet components or microsheet components. Therefore, even if the nanosheet layer or microsheet layer is separated from the growth substrate, it usually still does not represent the corresponding finished component. Fabricating a nanosheet component or microsheet component from the nanosheet layer or microsheet layer typically requires further processing steps. For example, such processing steps may involve cutting, sizing, deforming, or shaping the nanosheet layer or microsheet layer. In some (but not all) embodiments, the nanosheet layer or microsheet layer can correspond to the nanosheet component or microsheet component during the electrochemical delamination step.

[0019] If the thickness of an element (usually referring to its average thickness or median thickness) is in the nanometer or micrometer range, the element is regarded as a nanosheet element or a microsheet element. The nanometer range is 0.1 - 1000 nm, and the micrometer range is 0.1 - 1000 μm. Therefore, a nanosheet element or a microsheet element and / or a nanosheet layer or a microsheet layer can be composed of a single layer of carbon atoms or multiple layers of carbon atoms. In the case of multiple layers, the number of layers is preferably less than 1000 layers, more preferably less than 100 layers, and even more preferably less than 10 layers. A sheet refers to an element whose length and width are integer multiples of its thickness.

[0020] The nanosheet element or the microsheet element is preferably a functional element of an electronic device, such as a biosensor, an integrated circuit transistor (e.g., a CMOS-based microchip). The electronic device is particularly suitable for consumer electronics, medical technology, automotive engineering, optics, telecommunications, batteries, and aerospace technology. For example, it can be a Hall sensor, a capacitor (especially a supercapacitor), a photoelectric display, a current sensor, or a conductive layer, for use in, for example, injection-molded electronic products, transparent, wearable, and / or flexible electronic products. The nanosheet element or the microsheet element can also be used as part of a coating, such as a glass coating, or an anti-corrosion coating, or an anti-radiation coating, or a heat dissipation coating, or a hydrophobic / hydrophilic coating.

[0021] The nanosheet layer or the microsheet layer and the nanosheet element or the microsheet element are preferably but not necessarily made of graphene. In some embodiments, the nanosheet layer or the microsheet layer and the nanosheet element or the microsheet element can also be made of, for example, hexagonal boron nitride (hBN) or transition metal dichalcogenide (TMDC) or any other material. Alternatively, the nanosheet layer or the microsheet layer and the nanosheet element or the microsheet element can also be made of other thin sheet materials, such as thin films (referred to herein as brittle plastic films), polymer films, thermally evaporated or sputter-deposited metal films, micro-stamps, micro-molds, micro-patterns of polymer films or plastic films (by catalytic printing deposition), and such materials also need to be separated from their growth substrates.

[0022] Transition metal dichalcogenide (TMDC) is a class of two-dimensional semiconductor materials that contain transition metal atoms such as molybdenum (Mo), tungsten (W), and chalcogen atoms such as sulfur (S), selenium (Se), or tellurium (Te). Multiple types of TMDC are known, such as MoS2, MoSe2, WSe2, MoTe2, and WS2, where the metal atoms are sandwiched between the chalcogen atoms. TMDC is particularly preferably provided in a single layer form.

[0023] The laminate on which the method is based comprises at least a growth substrate, a nanosheet layer or a microsheet layer, and a carrier layer. Thus, the laminate forms the basis for the preparation of nanosheet elements or microsheet elements. In other words, the laminate is the basic component for the preparation of nanosheets or microsheet elements. The laminate is provided or prepared before performing the method. Of course, multiple nanosheet elements or microsheet elements can also be prepared by this method.

[0024] In addition to the growth substrate, the nanosheet layer or the microsheet layer, and the carrier layer, more than one additional layer may be present in the laminate. The nanosheet layer or the microsheet layer is preferably disposed between the growth substrate and the carrier layer. Before delamination, the layers of the laminate are usually adhered to each other over their entire surfaces. The nanosheet layer or the microsheet layer is preferably (usually directly) attached to the growth substrate. The carrier layer is preferably directly or indirectly attached to the nanosheet layer or the microsheet layer. The laminate preferably has the form of a wafer because it is commonly used in the semiconductor industry.

[0025] Electrochemical delamination of the laminate by electrolysis usually causes hydrogen bubbles to form between the growth substrate and the nanosheet layer or the microsheet layer, thereby causing a delamination effect between the layers.

[0026] In a particularly preferred embodiment, before the electrochemical delamination step, the carrier layer is patterned, in particular by photolithography patterning of the carrier layer or by directly placing a pre-patterned carrier layer. In the case of photolithography patterning, ultraviolet (UV) photolithography patterning can be particularly used. The lithography technique allows the carrier layer to be patterned directly on the nanosheet layer or the microsheet layer on the growth substrate. Alternatively or additionally, patterning can also be achieved by laser ablation or laser cutting, or by placing one or more parts of the carrier layer in a specific physical placement on the nanosheet layer or the microsheet layer. Alternatively or additionally, the pre-patterned carrier layer can be directly adhered to the nanosheet layer or the microsheet layer on the growth substrate by heating with heat.

[0027] The method may include an additional step of applying the nanosheet layer or the microsheet layer to the growth substrate, which can be achieved by, for example, chemical vapor deposition, physical sputtering, or electrodeposition, spin coating, screen printing, tape sticking, physical placement, or drop casting.

[0028] The method may further include an additional step of applying the carrier layer to the nanosheet layer or the microsheet layer, which can be achieved by, for example, spin coating, screen printing, tape, or physical placement. The carrier layer is preferably made of a polymer or plastic material.

[0029] Preferably, in the subsequent transfer after electrochemical delamination, the carrier layer has the function of adhering and supporting the nanosheet layer or microsheet layer on the target substrate. Therefore, the carrier layer provides structural stability for the nanosheet layer or microsheet layer. To this end, the carrier layer has intrinsic stability, that is, when the carrier layer is picked up and lifted from the edge, the carrier layer will not collapse or bend. Since the thickness of the nanosheet layer or microsheet layer is extremely small, it generally does not have intrinsic stability.

[0030] The multiple local depressions and / or protrusions of the pattern can be in the form of non-through holes or through holes. If in the form of through holes, the bottom of each local depression can be formed by an adjacent layer (such as a nanosheet layer or a microsheet layer).

[0031] Preferably, the growth substrate is made of a metal (such as copper, platinum or nickel), and the nanosheet layer or microsheet layer is synthesized, applied and / or prepared thereon.

[0032] In a particularly preferred embodiment, the method includes an additional step: after the electrochemical delamination step, transferring and preferably attaching the nanosheet layer or microsheet layer and the carrier layer to the target substrate. Preferably, the target substrate is adjusted to form the final device, and the nanosheet or microsheet element (constituted by the nanosheet layer or microsheet layer) is used and functions in the final device. During the transfer, the nanosheet layer or microsheet layer preferably remains attached to each other (especially bonded) with the carrier layer, but is separated from the growth substrate. In order to attach the nanosheet layer or microsheet layer to the target substrate, heat annealing is preferably applied.

[0033] The target substrate can be made of, for example, glass, polyimide or plastic. Its form can be, for example, an integrated chip or a flexible substrate. In a particularly preferred embodiment, the target substrate has more than one electrical contact. In this case, the nanosheet layer or microsheet layer is attached to the target substrate so that it connects these electrical contacts. The target substrate can have a pattern, which may or may not necessarily correspond to the pattern of the substrate layer. If the target substrate has a pattern, more than one depression can be formed for suspending the nanosheet layer or microsheet layer. More than one depression is particularly suitable for suspending the nanosheet layer or microsheet layer between two or more electrical contacts of the target substrate. In this case, each electrical contact is preferably placed on a local protrusion formed on the surface of the target substrate, or in each case, the electrical contact itself forms a local protrusion. "Suspension" means that the nanosheet layer or microsheet layer spans the corresponding depression of the target substrate, that is, the nanosheet layer or microsheet layer does not contact the bottom of the depression.

[0034] Preferably, during the transfer of the nanosheets or microsheets and the carrier layer to the target substrate, the nanosheets or microsheets are aligned with the target substrate using the pattern of the carrier layer. Since the base layer has been patterned during the electrochemical delamination step, this pattern can be used immediately when the nanosheets or microsheets and the carrier layer are separated from the growth substrate. For example, an image recognition and alignment system can be used to detect the pattern of the base layer and align the nanosheets or microsheets and the carrier layer with the target substrate. Thus, the nanosheets or microsheets can be correctly and automatically positioned on the target substrate.

[0035] Preferably, the image recognition and alignment system (if present) includes at least one camera that faces the nanosheets or microsheets and / or the target substrate during the transfer.

[0036] The target substrate may include one or more microchips. In particular, the microchips can be electrically connected to electrical contacts provided on the target substrate, which are preferably used to contact the nanosheets or microsheets or components. The microchips can have functions such as computing, sensing, and / or control units, for example.

[0037] In a further preferred step of the method, the carrier layer is removed from the nanosheets or microsheets after the transfer. The removal can be achieved, for example, by physical removal (such as peeling), or etching, or solvent-assisted dissolution.

[0038] Preferably, the transfer of the nanosheets or microsheets and the carrier layer to the target substrate is carried out by a pick-up element. The pick-up element can include a forklift. The size of the pick-up element (especially the forklift) is particularly adapted to the nanosheets or microsheets so that it can grasp and lift the nanosheets or microsheets and transfer them to the target substrate. Preferably, the forklift has a C-shaped part that serves as the contact point and pick-up point for the nanosheets or microsheets and extends horizontally during the transfer. In addition to the forklift, the pick-up element can also include a structure with a single extension or more than two parallel or non-parallel extensions that serve as the contact point and pick-up point for the nanosheets or microsheets and extend horizontally during the transfer.

[0039] Preferably, the pick-up element (especially the forklift, more specifically its C-shaped part) includes a magnetic element (especially an electromagnetic element) and / or a suction element for picking up the nanosheets or microsheets and the carrier layer. If the pick-up element (especially the forklift) includes a magnetic element, the nanosheets or microsheets or (more preferably) the carrier layer includes a corresponding element, such as a ferromagnetic element, for being attracted and bonded by the magnetic element of the pick-up element.

[0040] The same or another pick-up element, in particular a fork-like gripper, can also be used to handle the target substrate with attached nano- or micro-sheet layers, for example for removing the carrier layer and / or the polymer layer (see below).

[0041] The nanosheet or microsheet layer may have a uniform thickness covering its entire surface, or may be configured to have local protrusions and / or depressions. The depressions may be non-through or through, i.e., in the latter case, in the form of through holes. In particular, the structure may be provided to distinguish or separate multiple nanosheet or microsheet elements formed by the nanosheet or microsheet layer. The structure may be provided to the nanosheet or microsheet layer by, for example, laser ablation, laser cutting, UV lithography, or physical placement. In certain embodiments, the nanosheet or microsheet layer has a structure corresponding to the pattern of the carrier layer.

[0042] In a particularly preferred embodiment, a polymer layer is provided between the nanosheet or microsheet and the supporting layer. The polymer layer may be made of a material different from or the same as the supporting layer. In particular, it may be made of a plastic material. The method may comprise an additional step of fixing the polymer layer to the nanosheet or microsheet, which step may be achieved, for example, by spin coating, screen printing, tape or physical placement. Preferably, the polymer layer is fixed to the nanosheet or microsheet before the electrochemical delamination step. The polymer layer may, for example, have the function of providing additional structural stability to the nanosheet or microsheet and the supporting layer, or the polymer layer may be provided to achieve adhesion between the nanosheet or microsheet and the supporting layer. In certain embodiments, the polymer layer may also be provided to achieve certain functions in the final device.

[0043] The polymer layer may have a uniform thickness, i.e., no pattern, or may have a pattern that is different from or the same as that of the carrier layer. Preferably, the pattern of the polymer layer is formed by a plurality of local protrusions and / or depressions, which may be non-through or through. The pattern of the polymer layer may be formed by, for example, laser ablation, laser cutting, UV lithography, or direct stamping.

[0044] The polymer layer is preferably, but not necessarily, removed from the nanosheet or microsheet layer after transfer. Removal can be achieved, for example, by physical removal (eg, peeling), or by etching, or by dissolving in a solvent.

[0045] In addition to or in place of the polymer layer, any number of other layers may be disposed between the nanosheet or microsheet layer and the carrier layer. Preferably, the other layers and the polymer layer are transferred to the target substrate along with the nanosheet or microsheet layer. The other layers and the polymer layer may be configured to correspond to the pattern of the carrier layer and / or the structure of the nanosheet or microsheet layer.

[0046] In a preferred embodiment, one or more spacer elements, marker elements, washers, and / or magnetic pickup elements are attached to the carrier layer. One or more spacer elements, marker elements, washers, and / or magnetic pickup elements are particularly useful for transferring the nanosheet layer or microsheet layer and the carrier layer to the target substrate. For example, the marker element attached to the carrier layer can be used by an image recognition and alignment system to align the carrier layer and the nanosheet layer or microsheet layer with the target substrate. Other marker elements can also be provided on the target substrate for the image recognition and alignment system to use for the same purpose. In this case, the marker element on the carrier layer can be aligned with the marker element on the target substrate during the transfer process, so as to correctly position the nanosheet layer or microsheet layer on the target substrate.

[0047] In other embodiments, a frame can be attached to the carrier layer. For example, the frame can surround the area of the nanosheet element or microsheet element of the carrier layer. The frame can, for example, provide additional stability or make it convenient to handle through a fork gripper or other devices.

[0048] Electrolysis can be carried out based on a liquid electrolyte. In this case, the laminate is immersed in the electrolyte, and a voltage is applied between the anode and the cathode for delamination. The anode and the cathode are usually arranged on opposite sides of the interface between the nanosheet layer or microsheet layer and the growth substrate and are in contact with the electrolyte during this process. The growth substrate can be used to form the anode, or more preferably, to form the cathode. During the electrolysis process, hydrogen bubbles are formed at the interface between the nanosheet layer or microsheet layer and the growth substrate, resulting in the separation of the nanosheet layer or microsheet layer from the growth substrate.

[0049] Preferably, when performing electrochemical delamination, the laminate is fixed in a vertical or inclined position by a substantially L-shaped sample holder. Preferably, the laminate is immersed in the electrolyte together with the sample holder.

[0050] In some embodiments, a gas diffusion electrode can also be attached to the nanosheet layer or microsheet layer and used as the anode for the electrochemical delamination of the laminate. Thereafter, the cathode is preferably formed by the growth substrate. The gas diffusion electrode is preferably made of a porous material to allow specific gas exchange through the electrode.

[0051] As previously mentioned, electrochemical stratification can be performed using a liquid electrolyte. However, in certain embodiments, a dry electrolyte can be used for electrochemical stratification. In this case, the electrolyte is preferably formed by a polymer electrolyte membrane, which is arranged between the gas diffusion electrode and the nanosheet or microsheet layer during the electrochemical stratification of the laminate. And in this case, the cathode is preferably composed of a growth substrate. The gas diffusion electrode and the polymer electrolyte membrane are typically attached to the laminate in the following manner: the nanosheet or microsheet layer and the supporting layer are arranged between the growth substrate (on one side) and the gas diffusion electrode and the polymer electrolyte membrane (on the other side).

[0052] Therefore, during the electrolysis process, protons can diffuse through the gas diffusion electrode or penetrate from the side to form hydrogen bubbles, thereby generating a delamination effect that separates the nanosheets or microsheets from their growth substrate. Therefore, proton diffusion is not only facilitated through the gas diffusion electrode but can also be accelerated during the delamination process at defects such as grain boundaries and / or substrate wrinkles.

[0053] By using an electrolyte membrane (i.e., a solid electrolyte) for electrochemical layering, the problems associated with commonly used liquid electrolytes can be essentially avoided or at least reduced. The use of an electrolyte membrane can significantly reduce contamination of the nanosheets or microsheets by electrolyte substances during electrochemical layering. As a result, not only can nanosheet elements or microsheet elements be produced efficiently and on a large scale in industrial production, but their extremely high quality can also be ensured. In addition, the use of an electrolyte membrane simplifies the handling of laminates and electrolytic components. Moreover, compared to electrolysis using liquid electrolytes, this method can significantly reduce excess waste and lower production costs.

[0054] In certain embodiments, the nanosheet or microsheet may be a heterostructure formed by stacking multiple sublayers. Alternatively or additionally, the nanosheet element or microsheet element may be a heterostructure formed by stacking multiple sublayers, and the method further comprises the step of stacking the nanosheet or microsheet on at least one other nanosheet or microsheet. In various cases, the sublayers of the heterostructure are preferably two-dimensional extended crystals, i.e., lamellar crystals. Those skilled in the art generally refer to heterostructures formed by stacking multiple sublayers as van der Waals heterostructures. In certain embodiments, all sublayers of the heterostructure may be made of the same material and, in particular, have the same crystal structure. In other embodiments, the sublayers of the heterostructure may be made of different materials and / or have different crystal structures. For example, some sublayers may be made of graphene, while other sublayers may be made of hexagonal boron nitride, TMDC or other materials. In particular, the nanosheet or microsheet and / or nanosheet element or microsheet element may be made by die-by-die transfer technology. In this case, multiple sub-layers can be assembled into a heterostructure by die transfer technology, where each sub-layer or a subset of sub-layers is transferred in a different die to be stacked on one or more other sub-layers. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] The following describes the preferred embodiments of the present invention in conjunction with the accompanying drawings, which is intended to illustrate the preferred embodiments of the present invention rather than to limit the present invention.

[0056] Figure 1 shows a schematic cross-sectional view of a laminate having a growth substrate, a nanosheet layer or a microsheet layer, and a carrier layer before delamination according to a first embodiment of the present invention;

[0057] Figure 2a shows the transfer to the target substrate after electrochemical delamination Figure 1 Nanosheet or microsheet layers and carrier layers of the mid-laminate;

[0058] Figure 2b Shows completion Figure 2a After the transfer, the nanosheet layer or microsheet layer and the supporting layer are attached to the target substrate;

[0059] Figure 2c Shows completion Figure 2a After the transfer and removal of the carrier layer and other layers, the nanosheet layer or microsheet layer is attached to the target substrate;

[0060] Figure 3a shows the transfer to another different target substrate after electrochemical delamination. Figure 1 Nanosheet or microsheet layers and carrier layers of the mid-laminate;

[0061] Figure 3b Shows completion Figure 3a After the transfer, the nanosheet layer or microsheet layer and the supporting layer are attached to the target substrate;

[0062] Figure 3c Shows completion Figure 3a After the transfer and removal of the carrier layer and other layers, the nanosheet layer or microsheet layer is attached to the target substrate;

[0063] Figure 4a shows the transfer to a different target substrate after electrochemical delamination. Figure 1 Nanosheet or microsheet layers and a carrier layer in the mid-laminate;

[0064] Figure 4b Shows completion Figure 4a After the transfer, the nanosheet layer or microsheet layer and the supporting layer are attached to the target substrate;

[0065] Figure 4c Shows completion Figure 4a After the transfer and removal of the carrier layer and other layers, the nanosheet layer or microsheet layer is attached to the target substrate;

[0066] Figure 5 shows a schematic cross-sectional view of a laminate having a growth substrate, a nanosheet layer or a microsheet layer, and a carrier layer before delamination according to a second embodiment of the present invention;

[0067] Figure 6a shows the transfer to the target substrate after electrochemical delamination. Figure 5 Nanosheet or microsheet layers and carrier layers of the mid-laminate;

[0068] Figure 6b Shows completion Figure 6a After the transfer, the nanosheet layer or microsheet layer and the supporting layer are attached to the target substrate;

[0069] Figure 6c Shown in the completion Figure 6a After the transfer and removal of the carrier layer and other layers, the nanosheet layer or microsheet layer is attached to the target substrate;

[0070] Figure 7a shows the transfer to another different target substrate after electrochemical delamination. Figure 5 Nanosheet or microsheet layers and carrier layers of the mid-laminate;

[0071] Figure 7b Shows completion Figure 7a After the transfer, the nanosheet layer or microsheet layer and the supporting layer are attached to the target substrate;

[0072] Figure 7c Shown in the completion Figure 7a After the transfer and removal of the carrier layer and other layers, the nanosheet layer or microsheet layer is attached to the target substrate;

[0073] Figure 8a shows the transfer to a different target substrate after electrochemical delamination. Figure 5 Nanosheet or microsheet layers and carrier layers of the mid-laminate;

[0074] Figure 8b Shows completion Figure 8a After the transfer, the nanosheet layer or microsheet layer and the supporting layer are attached to the target substrate;

[0075] Figure 8c Shown in the completion Figure 8a After the transfer and removal of the carrier layer and other layers, the nanosheet layer or microsheet layer is attached to the target substrate;

[0076] Figure 9 shows a schematic cross-sectional view of a laminate having a growth substrate, a nanosheet layer or a microsheet layer, and a carrier layer before delamination according to a third embodiment of the present invention;

[0077] Figure 10 shows a schematic cross-sectional view of a laminate having a growth substrate, a nanosheet layer or a microsheet layer, and a carrier layer before delamination according to a fourth embodiment of the present invention;

[0078] Figure 11 shows a schematic cross-sectional view of a laminate having a growth substrate, a nanosheet layer or a microsheet layer, and a carrier layer before delamination according to a fifth embodiment of the present invention;

[0079] Figure 12 shows a schematic cross-sectional view of a laminate having a growth substrate, a nanosheet layer or a microsheet layer, and a carrier layer before delamination according to a sixth embodiment of the present invention;

[0080] Figure 13 shows a schematic cross-sectional view of a laminate having a growth substrate, a nanosheet layer or a microsheet layer, and a supporting layer before delamination according to a seventh embodiment of the present invention;

[0081] Figure 14 shows a schematic cross-sectional view of a laminate having a growth substrate, a nanosheet layer or a microsheet layer, and a supporting layer before delamination according to an eighth embodiment of the present invention;

[0082] Figure 15 shows a schematic cross-sectional view of a laminate having a growth substrate, a nanosheet layer or a microsheet layer, and a supporting layer before delamination according to a ninth embodiment of the present invention;

[0083] Figure 16 Shows a laminate fixed by a sample holder according to a first variant being immersed in an electrolyte for electrochemical delamination;

[0084] Figure 17 Shows a laminate fixed by a sample holder according to a second variant being immersed in an electrolyte for electrochemical delamination;

[0085] Figure 18 Shows a sample holder according to a third variant for immersing a laminate in an electrolyte for electrochemical delamination;

[0086] Figure 19a Shows a schematic perspective view of a first variant of a forked gripper that can be used to transfer a nanosheet layer or a microsheet layer and a carrier layer to a target substrate;

[0087] Figure 19b Shows Figure 19a the bottom surface of the forked gripper in, including a suction element and an electromagnetic element;

[0088] Figure 20a Shows a schematic perspective view of a second variant of a forked gripper that can be used to transfer a nanosheet layer or a microsheet layer and a carrier layer to a target substrate;

[0089] Figure 20b Shows Figure 20a the bottom surface of the forked gripper in, including a suction element and an electromagnetic element;

[0090] Figure 21 Shows a schematic perspective view of an image recognition and alignment system during the transfer of a nanosheet layer or a microsheet layer and a carrier layer to a target substrate by a forked gripper;

[0091] Figure 22 Shows a schematic cross-sectional view of a laminate to be electrochemically delaminated using a dry electrolyte, where for illustrative purposes, the nanosheet layer or microsheet layer and the growth substrate are shown separately. Detailed Description

[0092] Figures 1 to 22 Shows various inventive embodiments of the claimed method and its method steps. Figures 1 to 22 Also shows the elements, components, and parts for implementing the corresponding method or method steps. It should be noted that the combinations of the elements, components, and parts shown in the figures should only be understood as non-limiting examples. The individual elements, components, and parts in the described and / or illustrated embodiments can basically be replaced with each other as needed and can be supplemented with, for example, other elements. Elements, components, and parts having the same or similar functions in different embodiments or variants are labeled with the same reference numerals in the figures.

[0093] Figure 1 A laminate 14 is shown that includes a growth substrate 1, a nanosheet or microsheet layer 2, an optional polymer layer 4, and a carrier layer 3, which are bonded together in this order and, in each case, over their entire surfaces. The growth substrate 1 is typically made of a metal (such as copper) and is used to grow the nanosheet or microsheet layer 2 in a previous preparation step. For this purpose, the nanosheet or microsheet layer 2 can be applied to the growth substrate 1, for example, by chemical vapor deposition or spin coating. The nanosheet or microsheet layer 2 is preferably made of graphene, but can also be made of, for example, hexagonal boron nitride, or TMDC, or any other material. The growth substrate 1 and the nanosheet or microsheet layer 2 have a uniform thickness over their entire surfaces. The laminate 14 preferably has the form of a wafer, which is commonly used in the production of components in the semiconductor industry.

[0094] As can be seen from Figure 1 the cross-sectional view, the carrier layer 3 has a pattern 31 that consists of a plurality of local depressions 311 and protrusions 312. The depressions 311 and protrusions 312 are regularly distributed on the surface of the carrier layer 3. The depressions 311 are through-going depressions, meaning that they extend from the front surface to the back surface of the carrier layer 3. In this embodiment, the bottom of the depressions 311 is formed by the front surface of the polymer layer 4. The pattern 31 can serve, for example, as a marker for subsequent transfer and correct positioning of the carrier layer 3 and the nanosheet or microsheet layer 2 onto a target substrate.

[0095] The operation of applying the carrier layer 3 onto the polymer layer 4 can be carried out, for example, by spin coating or by directly placing a pre-patterned carrier layer 3. Preferably, the generation of the pattern 31 is accomplished by ultraviolet lithography and / or laser ablation. Alternatively, different parts of the pattern 31 (such as a plurality of local protrusions 312 in the form of island-like components) can also be physically placed on the polymer layer 4 and attached thereto, for example, by an adhesive.

[0096] The polymer layer 4 disposed between the nanosheet or microsheet layer 2 and the carrier layer 3 provides rigidity to the overall structure, and this property is particularly significant after the delamination of the growth substrate 1 in a subsequent step. This layer also increases the overall thickness of the laminate 14, which is beneficial for the handling of the laminate 14, especially after the removal of the growth substrate 1. The polymer layer 4 also serves to protect the nanosheet or microsheet layer 2 from external influences. The operation of applying the polymer layer 4 onto the nanosheet or microsheet layer 2 can be achieved, for example, by spin coating, spraying, or by directly placing the polymer layer 4.

[0097] In Figure 1In the illustrated embodiment, a spacer element 5 is provided on the front surface of the carrier layer 3. The spacer element 5 can be made of, for example, a plastic material and is used to facilitate the picking up and / or lifting of the sample after the growth substrate 1 is laminated. According to this embodiment, the spacer element 5 can be in the form of a plurality of small cubic elements or in the form of a single frame surrounding the front surface of the carrier layer 3.

[0098] In addition to or as an alternative to the spacer element 5, a marking element, a washer and / or a magnetic picking element can also be provided on the front surface of the carrier layer 3. The shapes of the marking element, the washer and / or the magnetic picking element can be the same as or different from those of the spacer element 5.

[0099] In order to remove the growth substrate 1 from the laminate 14, electrochemical delamination is carried out by electrolysis. During the electrolysis process, hydrogen bubbles are formed between the growth substrate 1 and the nanosheet layer or the microsheet layer 2, resulting in a delamination effect between the two layers. Thus, the growth substrate 1 can be separated from the nanosheet layer or the microsheet layer 2 in a very short time without damaging the growth substrate 1 or leaving impurities on the nanosheet layer or the microsheet layer 2. Since the growth substrate 1 remains intact, it can be reused, for example, for growing another layer of nanosheet layer or microsheet layer 2.

[0100] As shown in Figure 2a After the electrochemical delamination of the laminate 14, the sample containing the nanosheet layer or the microsheet layer 2, the polymer layer 4, the carrier layer 3 and the spacer element 5 is transferred to the target substrate 6. Through the pattern 31, the sample can be conveniently positioned and aligned with the target substrate 6 without any additional measures by the image recognition and alignment system 16 (see Figure 21 ). Figure 2b The target substrate 6 with the sample attached to its front surface is shown. The nanosheet layer or the microsheet layer 2 is directly attached to the front surface of the target substrate 6. In order to attach the nanosheet layer or the microsheet layer to the target substrate 6, heat annealing is preferably applied.

[0101] As the next step in the final device preparation, the polymer layer 4 and the carrier layer 3 attached with the spacer element 5 are removed from the nanosheet layer or the microsheet layer 2. This step can be achieved, for example, by rinsing with a suitable solvent or thermal separation. Figure 2c The final device is shown, in which the nanosheet layer or the microsheet layer 2 is attached to the target substrate 6, but the polymer layer 4, the carrier layer 3 and the spacer element 5 are absent.

[0102] Figure 3a -c and 4a-c show the transfer of the same sample as in Figure 2a -c to different target substrates 6. In Figure 3a -c, the target substrate 6 includes electrical contacts 61, which form local protrusions on the front surface of the target substrate 6 in various cases. In Figure 3cIn the final device shown, the electrical contact 61 is contacted and connected through a nanosheet element or a microsheet element formed by the nanosheet layer or the microsheet layer 2. As Figure 3b shown, the nanosheet layer or the microsheet layer 2 is applied to the target substrate 6 in a specific manner so as to conform to the structured front surface of the target substrate 6. Thus, the nanosheet layer or the microsheet layer 2 is not only located on the local protrusions formed by the electrical contacts 61, but also at the bottom of the depressions between the electrical contacts 61.

[0103] In Figure 4a -c, the bottom of the depression between the raised electrical contacts 61 is in a concave shape. The sample is placed on the target substrate 6 in a specific manner such that the nanosheet layer or the microsheet layer 2 spans the depression between the electrical contacts 61 ( Figure 4b ). Thus, the nanosheet layer or the microsheet layer 2 only contacts the electrical contacts 61 of the target substrate 6 and does not contact other parts. In other words, here the nanosheet layer or the microsheet layer 2 is suspended above the depression of the target substrate 6 formed between the electrical contacts 61.

[0104] Figure 5 Another variant of the laminate 14 is shown. Figure 5 The laminate 14 in Figure 1 differs from the laminate 14 in

[0105] Figure 5 in the structural configuration of the nanosheet layer or the microsheet layer 2 and the polymer layer 4. Both of these two layers include a structure with local protrusions and depressions. In various cases, the depressions are through holes, which means that the front surface of the growth substrate 1 is exposed within the depressions. The protrusions formed by the nanosheet layer or the microsheet layer 2 may or may not be interconnected. Here, the carrier layer 3 is patterned in a specific manner such that part of the front surface of the polymer layer 4 is also exposed. Figure 6a ), and attached to the target substrate 6 ( Figure 6b ). After removing the polymer layer 4, the carrier layer 3 and the spacer element 5, only the nanosheet layer or the microsheet layer 2 remains and together with the target substrate 6 constitutes the final device ( Figure 6c ).

[0106] Figure 7a -c and 8a-c show the transfer of the same sample as in Figure 6a -c to different target substrates 6. In Figure 7a -c, the target substrate 6 includes electrical contacts 61, which form local protrusions on the front surface of the target substrate 6 in various cases. In Figure 7cIn the final device shown, the electrical contacts 61 are contacted and connected by the nanosheet elements or microsheet elements formed by the nanosheet layer or microsheet layer 2. Figure 7b As shown, the nanosheet or microsheet layer 2 is applied to the target substrate 6 in a specific manner so that it conforms to the structured front surface of the target substrate 6. Therefore, the nanosheet or microsheet layer 2 is not only located on the local protrusions formed by the electrical contacts 61, but also located at the bottom of the recesses between the electrical contacts 61. However, due to the structure of the nanosheet or microsheet layer 2, some recesses of the target substrate 6 are not covered, which means that each electrical contact 61 does not necessarily need to be interconnected with all other electrical contacts 61.

[0107] exist Figure 8a In the embodiment shown in FIG-c, the bottom of the depressions formed between the raised electrical contacts 61 are partially lowered. The sample is placed on the target substrate 6 in a specific manner so that the nanosheet or microsheet layer 2 spans these lowered depressions between the electrical contacts 61 (see FIG-c). Figure 8b ). Therefore, the nanosheet or microsheet layer 2 contacts only the electrical contacts 61 of the target substrate 6 and does not contact other portions. In other words, the nanosheet or microsheet layer 2 is suspended above the corresponding depressions in the target substrate 6 formed between the electrical contacts 61. In the areas where the depressions are not lowered, the target substrate 6 is not covered by the nanosheet or microsheet layer 2.

[0108] Figures 9 - 15 Shows the Figure 1 and Figure 5 Other variations of laminate 14 besides . Figure 9 The laminate 14 and Figure 1 The laminate 14 in FIG. 1 is different in that an isolation layer 7 is added between the nanosheet or microsheet layer 2 and the polymer layer 4. The isolation layer 7 provides an electrical isolation function.

[0109] Figure 10 The variant shown is the same as Figure 9 The variant shown differs in that the structure of its polymer layer 4 corresponds to the pattern 31 of the carrier layer 3. Thus, the bottom of the individual recesses 311 in the pattern 31 is formed in each case by the isolation layer 7.

[0110] exist Figure 11 In the variant shown, the isolation layer 7 and the nanosheet or microsheet layer 2 are also structured. Here, the polymer layer 4 , the isolation layer 7 and the nanosheet or microsheet layer 2 all have the same structure corresponding to the pattern 31 of the carrier layer 3 .

[0111] Figure 12 A variant is shown in which the isolation layer 7 is disposed between the nanosheet or microsheet layer 2 and the polymer layer 4. Here, the isolation layer 7 extends into the through-hole formed by the nanosheet or microsheet layer 2, so that the through-hole is completely filled with the isolation layer 7.

[0112] Figure 13 shows the same laminate 14, but the nanosheet layer or microsheet layer 2 and the polymer layer 4 are additionally structured according to the pattern 31 of the carrier layer 3. Through this structuring, the bottom of the depression 311 is formed by the front surface of the growth substrate 1 that is exposed. Figure 1 The variant shown is the same as

[0113] Figure 14 the variant shown, except that here the nanosheet layer or microsheet layer 2 has a uniform thickness, i.e., a structure without depressions or protrusions. Figure 13 The variant of the laminate 14 shown is different from

[0114] Figure 15 the variant shown in that an isolation layer 7 is added. The isolation layer 7 has the same structure with protrusions and depressions as the nanosheet layer or microsheet layer 2 and the polymer layer 4. Figure 5

[0115] Figure 16 17 and Figure 16 show an electrolytic electrochemical delamination process based on two variants. For this purpose, the laminate 14 is placed vertically and clamped in a substantially L-shaped sample holder 11, and the laminate 14 and the sample holder 11 are immersed together in a beaker 8 containing an electrolyte 9 (see ). The laminate 14 is clamped by a clamp 12 connected to the sample holder 11. To facilitate the handling and clamping of the laminate 14 through the growth substrate 1, the nanosheet layer or microsheet layer 2 and the other layers 3 and 4 are present only on a partial surface of the growth substrate 1, rather than the entire surface. When performing electrochemical delamination, the anode 10 is additionally immersed in the electrolyte 9, and a voltage is applied between the anode 10 and the metal growth substrate 1. Thereby, the growth substrate 1 forms a cathode in the electrolysis. The connection wire 13 is used to apply a voltage to the growth substrate 1.

[0116] Figure 17 Figure 16 The sample holder 11 in Figure 17 is different from the sample holder in in that there is a bend at the fixing part. The shape of the growth substrate 1 is adjusted accordingly. Thereby, during electrolysis, when using the sample holder 11 shown in

[0117] Figure 16 17 and Figure 18 as well as In the laminates shown, each carrier layer 3 includes a pattern 31, but for the sake of illustration, this pattern is not shown.

[0118] Figure 18 ​FIG. 1 shows another possible design of the sample holder 11 . Here, the growth substrate 1 is fixed in both areas above and below the carrier layer 3 .

[0119] Figure 19a A first version of a pickup element in the form of a fork-shaped gripper 15 is shown for transferring the nanosheet or microsheet layer 1 together with the carrier layer 3 and the polymer layer 4 (if present) from the growth substrate 1 to the target substrate 6 after delamination. In addition to the fork-shaped gripper, any other pickup element can be used for the same purpose. The fork-shaped gripper 15 includes a fork-shaped element 152, which is C-shaped and extends in the horizontal direction. A vertically extending support rod 151 is connected to the fork-shaped element 152 for fixing the fork-shaped element 152 and moving it in the three directions of space X, Y and Z. The upper end of the support rod 151 is connected to a corresponding processing device, such as a robotic arm (not shown in the figure).

[0120] The fork-shaped member 152 is used to contact, pick up, transfer and place the sample comprising the delaminated nanosheet or microsheet layer 2, the supporting layer 3 and the polymer layer 4 (if present). When transferring the sample, the fork-shaped member 152 can be moved under or over the sample and then lifted up so that the sample is supported on the upper surface of the fork-shaped member 152. However, the preferred embodiment of the fork-shaped gripper 15 is as follows Figure 19b As shown, an air suction element 155 and / or electromagnetic element 156 are disposed on the bottom surface of the fork-shaped element 152. Activating the air suction element 155 and / or electromagnetic element 156 attracts and secures the sample. When the sample is placed on the target substrate 6, the air suction element 155 and / or electromagnetic element 156 are deactivated again. To allow the sample to be attracted by the electromagnetic element 156, the sample includes a ferromagnetic component, such as a ferromagnetic pickup element attached to the upper surface of the carrier layer 3. The air suction element 155 and / or electromagnetic element 156 enable rapid sample transfer without damaging the sample.

[0121] Figure 20a and 20b A second version of the forked gripper 15 is shown. Here, a forked element 152 is connected to a vertically extending rack 153, which meshes with a gear 154. By rotating the gear 154 (which may be part of a corresponding motorized operating device), the forked gripper 15 can be moved in the vertical Z direction. The underside of the forked element 152 is equipped with a plurality of suction elements 155 and an electromagnetic element 156 in the form of a C-shaped magnetic strip.

[0122] Figure 21Shows the steps of correctly aligning a sample containing nanosheets or microsheets 2 with a target substrate 6 using an image recognition and alignment system 16. For this purpose, the image recognition and alignment system 16 includes a camera, such as a CCD camera, for photographing the upper surface of the target substrate 6 and the position and orientation of the fork-shaped element 152 with the nanosheets or microsheets 2 and the carrier layer 3. With the aid of the pattern 31 of the carrier layer 3 and the alignment marks 17 optionally provided on the target substrate 6, the fork-shaped element 152 is moved by a controller so that the nanosheets or microsheets 2 are correctly aligned and placed on the target substrate 6.

[0123] To fix the nanosheets or microsheets 2 by thermal annealing, the target substrate 6 can be placed on a heating plate 18, which can be heated for this purpose.

[0124] To bring the nanosheets or microsheets 2 closer to the target substrate 6 and / or to align these two elements, the heating plate 18 or other device for fixing the target substrate 6 can also be movable. For example, the heating plate 18 can rotate about a vertical axis as shown by the double arrow in [[ID=1 In addition, the heating plate 18 can also be moved along the vertical Z-axis and / or the X-axis and / or the Y-axis.

[0125] ​ Shows another variant of the steps of the electrochemical delamination method that does not use a liquid electrolyte. Instead, a polymer electrolyte membrane 20 attached to the front surface of the carrier layer 3 is used. The carrier layer 3 has a pattern 31, but it is not shown in ​ For the sake of illustration. If the pattern 31 includes a through-dimple 311, the polymer electrolyte membrane 20 can also have a corresponding dimple. An anodic gas diffusion electrode 21 is provided on the front surface of the electrolyte membrane 20. The upper surface of the anodic gas diffusion electrode 21 is connected to a holder 22. The holder 22 is made of a flexible or rigid material, such as polydimethylsiloxane (PDMS), and has a specific porosity and / or permeability such that water can pass through the holder 22. Therefore, water in the environment can pass through the holder 22, and hydrogen ions generated by the anodic gas diffusion electrode 21 can pass through the electrolyte membrane 20.

[0126] It should be noted that, only for the sake of illustration, ​ The carrier layer 3 and the nanosheets or microsheets 2 shown are spaced apart from each other by a certain distance. However, before, during, and after the actual electrochemical delamination, the carrier layer 3 and the nanosheets or microsheets 2 are attached to each other.

[0127] For electrochemical delamination by electrolysis, a source of water (H2O) is provided to the holder 22, and a voltage is applied between the anode gas diffusion electrode 21 and the growth substrate 1 by the power supply 19. The growth substrate 1 is made of copper (Cu) and forms the cathode. The voltage difference between the anode and the cathode causes water molecules (H2O) to split into hydrogen ions (H + +) and oxygen (O). Thereby, oxygen is generated at the anode (i.e., at the anode gas diffusion electrode 21). The hydrogen ions pass through the anode gas diffusion electrode 21, the polymer electrolyte membrane 20, the carrier layer 3, and the nanosheet layer or microsheet layer 2. Additionally or alternatively, H2O molecules can also enter from the environment (i.e., the side) between the layer interfaces. At the growth substrate 1, especially at the interface between the growth substrate 1 and the nanosheet layer or microsheet layer 2, hydrogen gas is formed. The generation of such hydrogen bubbles causes the separation of the growth substrate 1 from the nanosheet layer or microsheet layer 2, which means that the laminate 14 is delaminated in a dry manner, where the laminate 14 remains under dry conditions and does not need to be immersed in an electrolyte.

[0128] In another method, hydrogen gas (H2) is used as the source at the holder 22, and the anode gas diffusion electrode 21 and the growth substrate 1 are connected to an electrical load such that hydrogen ions are generated at the gas diffusion electrode 21, and the hydrogen ions diffuse through the polymer membrane 20, the carrier layer 3, and the nanosheet layer or microsheet layer 2. At the growth substrate 1, the hydrogen ions react with oxygen ions to form water, thereby causing the separation of the nanosheet layer or microsheet layer 2.

[0129] The present invention is of course not limited to the foregoing embodiments and can be modified in various ways. For example, the polymer layer 4 can be omitted in all embodiments. The elements disclosed in different embodiments can be replaced, omitted, or added. Various further modifications can also be made.

[0130] List of reference numerals

[0131] 1 Growth substrate 15 Fork-shaped gripper

[0132] 2 Nanosheet layer or microsheet layer 151 Support rod

[0133] 3 Carrier layer 152 Fork-shaped element

[0134] 31 Pattern 153 Rack

[0135] 311 Depression 154 Gear

[0136] 312 Protrusion 155 Suction element

[0137] 4 Polymer layer 156 Electromagnetic element

[0138] 5 Spacer element

[0139] 16 Image recognition and alignment system

[0140] 6 Target Substrate

[0141] 61 Electrical Contact 17 Alignment Mark

[0142] 7 Isolation Layer 18 Heating Plate

[0143] 8 Beaker 19 Power Supply

[0144] 9 Liquid Electrolyte 20 Polymer Electrolyte Membrane

[0145] 10 Anode

[0146] 11 Sample Holder 21 Anode Gas Diffusion Electrode

[0147] 12 Clamp

[0148] 13 Connecting Wire 22 Holder

[0149] 14 Laminated Part H2O H2O Flow Direction

Claims

1. A method for preparing a nanosheet element or a microsheet element based on a laminate (14), the nanosheet element or the microsheet element being made of graphene and / or other sheet materials, the laminate (14) having a growth substrate (1), a nanosheet layer or a microsheet layer (2), and a carrier layer (3), and adjusting the nanosheet layer or the microsheet layer (2) to form the nanosheet element or the microsheet element, Among them, The method at least includes an electrochemical delamination step of the laminate (14) by electrolysis, such that the growth substrate (1) is separated from the nanosheet layer or the microsheet layer (2) and the carrier layer (3), Characterized in that, The electrochemical delamination step of the laminate (14) is carried out through the carrier layer (3), the carrier layer (3) having a pattern (31), the pattern (31) having a plurality of local depressions (311) and / or protrusions (312).

2. The method according to claim 1, wherein, After the electrochemical delamination step, the nanosheet layer or the microsheet layer (2) and the carrier layer (3) are transferred to a target substrate (6).

3. The method according to claim 2, wherein, During transfer, the pattern (31) of the carrier layer (3) is used to align the nanosheet layer or the microsheet layer (2) with the target substrate (6).

4. The method according to claim 2 or 3, wherein After transfer, the carrier layer (3) is removed from the nanosheet layer or the microsheet layer (2).

5. The method according to any one of claims 2 to 4, wherein The nanosheet layer or the microsheet layer (2) and the carrier layer (3) are transferred to the target substrate (6) by a fork-shaped gripper (15), the fork-shaped gripper preferably including an electromagnetic element (156) and / or a suction element (155) for picking up the nanosheet layer or the microsheet layer (2) and the carrier layer (3).

6. The method according to any one of the preceding claims, wherein, The nanosheet layer or the microsheet layer (2) has a structure corresponding to the pattern (31) of the carrier layer (3).

7. The method according to any one of the preceding claims, wherein, A polymer layer (4) is provided between the nanosheet layer or the microsheet layer (2) and the carrier layer (3).

8. The method according to any one of the preceding claims, wherein, One or more spacer elements (5), marking elements, washers, and / or magnetic pickup elements are attached to the carrier layer (3).

9. The method according to any one of the preceding claims, wherein, The growth substrate (1) serves as the cathode for the electrochemical delamination of the laminate (14).

10. The method according to any one of the preceding claims, wherein, During electrochemical delamination, the laminate (14) is fixed in a vertical or inclined position by a substantially L-shaped sample holder (11).

11. The method according to any one of the preceding claims, wherein, A gas diffusion electrode (21) attached to the nanosheet layer or the microsheet layer (2) is used as the anode for the electrochemical delamination of the laminate (14).

12. The method according to claim 11, wherein, During the electrochemical delamination of the laminate (14), a polymer electrolyte membrane (20) is provided between the gas diffusion electrode (21) and the nanosheet layer or the microsheet layer (2).

13. The method according to claim 11 or 12, wherein, During the electrochemical delamination of the laminate (14), a holder (22) is connected to the gas diffusion electrode (21), the holder (22) having a porosity and / or a permeability to allow a liquid, especially water, to pass through the holder (22) to reach the gas diffusion electrode (21).

14. The method according to any one of the preceding claims, Among them, The nanosheet layer or the microsheet layer (2) is a heterostructure formed by stacking a plurality of sub-layers, and / or The nanosheet layer or microsheet layer is a heterostructure formed by stacking multiple sublayers, and the method further includes the step of stacking the nanosheet layer or microsheet layer (2) on at least one other nanosheet layer or microsheet layer.

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