Stripping method of ultrathin-layer two-dimensional material

Abstract

The embodiment of the invention discloses a stripping method of an ultrathin-layer two-dimensional material. The method comprises the steps that a two-dimensional material plate is cleaved into two-dimensional material sheets at least once through a heat release adhesive tape; carrying out surface roughening treatment on the bonding surface of the substrate sheet; the heat release adhesive tape pasted with the two-dimensional material sheet is pasted on the bonding surface of the substrate sheet, and the whole body is placed in a vacuum environment for pressure maintaining. Wherein the substrate is subjected to surface roughening treatment, and the whole sample assembly is subjected to vacuum pressure maintaining, so that the effective adsorption of the substrate to the two-dimensional material sheet can be improved, the viscosity of the substrate combined with the heat release adhesive tape is further promoted, and interlayer separation of the two-dimensional material sheet is facilitated under the upper and lower dual effects; the two-dimensional material sheets left by separation well keep the original smooth stacking property between material layers, that is, the section generated by stripping is smooth and large in area, and the situation that the actual application value of the material sheets is affected due to surface roughness and fragmentation is avoided.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of material technology, and in particular to a method for stripping ultra-thin layers of two-dimensional materials. Background Art

[0002] Two-dimensional materials such as single-crystal graphite and molybdenum disulfide, whose electrons can only move freely (planar motion) in two dimensions at the non-nanoscale (1-100nm), have many unique physical and chemical properties, such as high conductivity, high strength, low friction coefficient and heat resistance, which have attracted widespread attention in both basic research and applications.

[0003] Taking graphite as an example, in the field of ultra-slippery materials, in order to obtain sufficiently thin graphite flakes, in the existing process, lasers or chemical reagents are often used to directly peel off graphite flakes from graphite of a certain thickness. However, the graphite flakes peeled off in this way have a small area and many uneven areas, that is, the degree of fragmentation is large, and a large number of wrinkles are easily generated on the surface during the transfer process, thereby affecting its electrical and mechanical properties, and reducing the subsequent practical application value of graphite flakes made into graphite islands, etc. Summary of the invention

[0004] The embodiment of the present application provides a method for stripping ultra-thin layers of two-dimensional materials, which is used to easily strip off large-area two-dimensional material sheets with smooth surfaces and no defects, thereby improving the practical application value of the material sheets with high quality.

[0005] A first aspect of an embodiment of the present application provides a method for stripping an ultra-thin layer of two-dimensional material, comprising:

[0006] Cleavage the two-dimensional material sheet at least once through a thermal release tape into a two-dimensional material sheet, wherein the thickness of the two-dimensional material sheet is 1 to 10 micrometers;

[0007] The bonding surface of the base sheet is subjected to a surface roughening treatment; the bonding surface refers to the surface pre-bonded with the two-dimensional material sheet;

[0008] Affixing the heat release tape with the two-dimensional material sheet attached to the base sheet, and the two-dimensional material sheet is attached to the adhesive surface to form a sample assembly;

[0009] Placing the entire sample assembly in a vacuum environment, applying pressure, and maintaining the pressure for a preset time;

[0010] The thermal release tape is heated to separate the thermal release tape from the two-dimensional material sheet, thereby obtaining a two-dimensional material sheet that is separately attached to the base sheet.

[0011] Optionally, after the two-dimensional material plate is cleaved at least once into two-dimensional material flakes by means of a thermal release tape, before the thermal release tape with the two-dimensional material flakes attached thereto is attached to the base sheet, the method further comprises:

[0012] One of the main surfaces of the two-dimensional material sheet is etched to make the main surface clean and have a concave-convex structure; the main surface is parallel to the stacking direction of each material layer in the two-dimensional material sheet, and the main surface is pre-adhered to the thermal release tape and jointly attached to the base sheet.

[0013] Optionally, the etching process on one of the main surfaces of the two-dimensional material sheet includes:

[0014] The two-dimensional material sheet is placed in a reactive ion etching (RIE) device to perform an etching treatment for a preset time on one of the main surfaces of the two-dimensional material sheet.

[0015] Optionally, when the RIE equipment uses oxygen plasma for etching, the preset time length includes 1 to 3 minutes.

[0016] Optionally, the pressure of the environment in which the pressure-maintaining treatment is performed is below 10 Pa.

[0017] Optionally, the preset time of the pressure-maintaining process is 1 to 2 hours.

[0018] Optionally, the heating temperature is 100 to 200 degrees Celsius.

[0019] Optionally, the surface roughening treatment is performed by plasma sputtering.

[0020] Optionally, when the plasma sputtering treatment uses argon plasma to perform sputtering etching, the duration of the sputtering etching is 5 to 10 minutes.

[0021] Optionally, the two-dimensional material sheet is highly oriented pyrolytic graphite.

[0022] Optionally, after obtaining the two-dimensional material sheet attached to the base sheet alone, the method further comprises:

[0023] Performing film coating, gluing, exposure and development processing on the two-dimensional material sheet separately attached to the base sheet, so that the expected pattern appears on the two-dimensional material sheet;

[0024] The material above the developed two-dimensional material slice is etched to obtain a two-dimensional material island arranged based on the expected pattern.

[0025] It can be seen from the above technical solutions that the embodiments of the present application have at least the following advantages:

[0026] In the embodiment of the present application, the surface of the substrate sheet is roughened, and the sample assembly is placed in a vacuum environment for pressure maintenance. This can improve the effective adsorption of the substrate sheet to the two-dimensional material sheet, further promote the adhesion of the substrate sheet combined with the heat release tape, and help the two-dimensional material sheet to separate from each other through dual effects. The two-dimensional material sheet left after separation can well maintain the original flat stacking properties between the material layers, that is, the cross-section produced by peeling is flat and large, avoiding the actual application value of the material sheet affected by surface roughness and fragmentation. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0028] It should be noted that, although the steps in the process diagrams (if any) involved in the embodiments are drawn in sequence as indicated by the arrows, unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowcharts involved in the embodiments may include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least a portion of the steps or stages in other steps.

[0029] Figure 1 A schematic flow chart of a method for stripping an ultra-thin layer of two-dimensional material according to an embodiment of the present application;

[0030] Figure 2 A schematic diagram of the effect of the method for peeling off an ultra-thin layer of two-dimensional material according to an embodiment of the present application;

[0031] Figure 3 A schematic diagram of a wet etching process for a method for stripping an ultra-thin layer of two-dimensional material according to an embodiment of the present application;

[0032] Figure 4 Schematic diagram of the dry etching process of the ultra-thin layer two-dimensional material stripping method according to an embodiment of the present application. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings. The described embodiments should not be regarded as limiting the present application. All other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of this application.

[0034] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims and drawings of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0035] In the following description, similar expressions such as "a specific implementation" or "a specific example" are involved, which describe a subset of all possible embodiments, but it can be understood that "a specific implementation" or "a specific example" can be the same subset or different subsets of all possible embodiments, and can be combined with each other without conflict. In the following description, the term multiple refers to at least two. In some specific examples, the numerical value mentioned in this application reaches the threshold value (if any), which may include the case where the former is greater than the latter of the threshold value; if similar expressions such as "any" or "at least one" are mentioned, it can specifically refer to any one of the listed examples or any combination of these examples.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein are only for the purpose of describing the embodiments of this application and are not intended to limit this application.

[0037] The method of the present application will be described in further detail below.

[0038] See also Figure 1 In a first aspect, the present application provides some specific embodiments of a method for exfoliating an ultra-thin layer of two-dimensional material, the embodiment comprising the following steps:

[0039] Step S11, cleaving the two-dimensional material plate into two-dimensional material sheets at least once using a thermal release tape;

[0040] The above-mentioned two-dimensional material can specifically be a two-dimensional material such as graphite or molybdenum disulfide, and the graphite can be highly oriented pyrolytic graphite (HOPG) or natural graphite. For ease of explanation and understanding, the embodiments of the present application mainly use natural graphite as a two-dimensional material for exemplary explanation. In the experiment, a piece of natural graphite with a size of 1.2mm*1.2mm*(thickness)1mm can be cleaved more than once by a thermal release tape to obtain a graphite sheet with a thickness of 1 to 10 microns.

[0041] Step S12, performing surface roughening treatment on the bonding surface of the base sheet;

[0042] The above-mentioned base sheet can be a substrate such as a silicon (Si) sheet, a sapphire sheet or a glass sheet. This substrate is generally required to have a flat and clean surface and to have good van der Waals force with the two-dimensional material; the above-mentioned bonding surface refers to the surface that is pre-bonded with the two-dimensional material sheet. Of course, in some demand situations, other surfaces of the base sheet except the bonding surface can also be roughened, without specific limitation.

[0043] In some examples, the surface roughening treatment method can be a plasma sputtering treatment method. Taking Si wafer as an example, a clean Si wafer can be subjected to argon Ar plasma sputtering treatment, so that the bonding surface of the Si wafer is bombarded into a microporous surface, that is, a concave-convex structure is formed, thereby increasing the roughness of the bonding surface; the micropores mentioned in each embodiment of the present application mainly refer to non-through grooves. Compared with a smooth surface, the above-mentioned concave-convex structure can subsequently utilize its own microporous gaps to enhance the adhesion between the base sheet and the graphite layer, facilitate the subsequent bonding tape adhesion, and allow the graphite to separate from the layers by dual action of the upper and lower layers, thereby further thinning to obtain a large-area graphite sheet with a smooth surface.

[0044] Of course, in some examples, plasma sputtering treatment can be performed with an inert gas other than Ar, or with oxygen. The above plasma sputtering treatment mainly uses Ar because the applicant has found through multiple experiments that the inert gas Ar plasma, due to its high ionization rate, can easily form a surface microstructure when treating the substrate, and combined with vacuum negative pressure exhaust, it can increase the physical adsorption force between graphite and the substrate. In addition, in comparison, the use of Ar plasma + vacuum negative pressure treatment currently has a better effect, while the effect and success rate of stripping large-area and flat graphite using oxygen or nitrogen plasma treatment are much worse.

[0045] In some specific examples, when Ar is used, the corresponding plasma sputtering treatment time can be within 5 to 10 minutes, which can be set according to actual conditions and is not limited here.

[0046] Step S13, attaching the thermal release tape with the two-dimensional material sheet to the base sheet, and attaching the two-dimensional material sheet to the adhesive surface to form a sample assembly;

[0047] The lower surface of the graphite with the heat release tape on the upper surface can be adhered to the bonding surface of the Si wafer after the plasma sputtering treatment to form a sample assembly as a whole.

[0048] Step S14, placing the entire sample assembly in a vacuum environment, applying pressure, and maintaining the pressure for a preset time;

[0049] Exemplarily, the above-mentioned sample assembly is placed in a vacuum device for pressure treatment. Here, placing the sample assembly in a vacuum environment for pressure treatment helps to discharge the gas on the microporous surface of the substrate to form a low pressure, thereby increasing the physical adsorption force between the graphite and the substrate; similarly, it can promote the discharge of gas between the thermal release tape and the graphite, increase the physical adsorption force between the two, and further ensure the possibility of thinning the graphite again through the double suction of the upper and lower forces.

[0050] In some specific examples, the ambient pressure of the above-mentioned pressure-holding treatment can be below 10Pa; the preset time of the pressure-holding process can be 1 to 2 hours. Of course, the ambient pressure and pressure-holding time used for the pressure-holding treatment can be set according to actual conditions and are not limited here.

[0051] Step S15, heating the thermal release tape to separate the thermal release tape from the two-dimensional material sheet, thereby obtaining a two-dimensional material sheet that is separately attached to the base sheet.

[0052] The sample assembly can be placed on a heating table for heating, so that the heat release tape fails due to heating (i.e. loses its stickiness) and the two-dimensional material sheet can be released onto the substrate. In view of the implementation of the vacuum pressure treatment, the heat release of the heat release tape can tear off at least one layer of graphite on the surface, that is, the original graphite sheet can be peeled off from the middle layer due to the effective adsorption force of the upper and lower surfaces, such as making the graphite sheet stacked by n layers of graphite be peeled off less than n layers, thereby achieving the thinner sheet production requirements.

[0053] In some specific examples, the temperature for heating the heat release tape may be 100 to 200 degrees Celsius. Of course, this may be set according to actual conditions as long as the heat release tape can be rendered ineffective. This is not limited here.

[0054] In summary, in the embodiments of the present application, the surface of the substrate sheet is roughened, and the sample assembly as a whole is placed in a vacuum environment for pressure maintenance treatment, which can improve the effective adsorption of the substrate sheet to the two-dimensional material sheet, further promote the adhesion of the substrate sheet combined with the heat release tape, and help the two-dimensional material sheet to separate from each other through dual effects from top to bottom, so that the two-dimensional material sheet left after separation can well maintain the original flat stacking properties between the material layers, that is, the cross-section produced by peeling is flat and large, avoiding the actual application value of the material sheet affected by surface roughness and fragmentation.

[0055] See also Figure 2 Based on the above example descriptions, some specific possible implementation examples will be provided below. In actual applications, the implementation contents between these examples can be combined or implemented separately as needed according to the corresponding functional principles and application logic. If implemented in combination, the execution order between the combined examples can be determined according to their respective processing logics, which can be determined by the actual scenario.

[0056] based on Figure 1 In some specific examples, the cleavage process of step S11 can be implemented by combining the use of polymer fiber tape (such as 3M brand tape) and thermal release tape. For example, the upper and lower surfaces of graphite can be respectively affixed with 3M brand tape and thermal release tape, and by peeling off one or both of the tapes, the graphite can be peeled off from each other, thereby obtaining gradually thinned graphite.

[0057] based on Figure 1 In some specific examples, after step S11 and before step S13, the method of the embodiment of the present application can also: etch one of the main surfaces of the two-dimensional material sheet so that the main surface is clean and has a concave-convex structure; the main surface is parallel to the stacking direction of each material layer in the two-dimensional material sheet, and the main surface is pre-bonded with a thermal release tape and jointly attached to the base sheet.

[0058] Exemplarily, the upper surface (or main surface) of the graphite sheet can be etched so that the main surface is clean and has a concave-convex structure, that is, it presents a microporous rough surface. The above-mentioned main surface is parallel to the stacking direction of each material layer in the two-dimensional material sample. For example, the graphite sample is generally stacked up and down by each layer of graphite layer, so the exposed surface of the uppermost and lowermost graphite layers can be called the main surface of the graphite sample. For ease of explanation, the embodiment of the present application mainly uses the exposed surface of the uppermost graphite layer as the etched main surface. Compared with the smooth surface, the above-mentioned concave-convex structure can subsequently utilize the microporous gap to enhance the adhesion between the tape and the graphite layer, which is convenient for the subsequent peeling of the flat sample sheet from the interlayer through the adhesion of the tape, that is, to achieve the effect of thinning the graphite.

[0059] In some specific examples, the above-mentioned etching process may specifically include: placing the two-dimensional material sheet into a reactive ion etching (RIE) device to perform an etching process for a preset time on one main surface of the two-dimensional material sheet.

[0060] In some specific examples, if the above RIE equipment uses oxygen plasma for etching, the preset etching time may include 1 to 3 minutes. Of course, the specific time may be set according to the actual situation and is not limited here.

[0061] In summary, the method of the embodiment of the present application is to transfer graphite after sputtering the substrate with Ar plasma, and combine it with vacuum pressure treatment, so that effective physical adsorption can be formed on the bottom graphite without a binder; in addition, the graphite transferred by the embodiment of the present application is in direct rigid contact with the substrate (i.e., no adhesive is required in the middle), and the peeled surface is pollution-free. In contrast, the graphite sheets prepared by the existing method are small and broken, and are often accompanied by defects such as a certain degree of stepped surface (i.e., uneven cross-section), and the thickness of most graphite sheets is not thin enough; and after adopting the method of the embodiment of the present application, large pieces of thin graphite sheets with a flat surface and no defects of ten microns or less can be easily peeled off, and this defect-free and flat two-dimensional material (graphite, molybdenum disulfide, etc.) at the level of ten microns or less also has a wider value in practical applications. Therefore, the method of the embodiment of the present application can also be called a large-area peeling and transfer process of two-dimensional materials on substrates.

[0062] based on Figure 1 In some specific examples, after step S15, the method of the embodiment of the present application may also include (micro-processing the two-dimensional material sheet to form a two-dimensional material island): coating, gluing, exposing and developing the two-dimensional material sheet separately attached to the substrate sheet so that the expected pattern appears above the two-dimensional material sheet; etching the material above the developed two-dimensional material sheet to obtain a two-dimensional material island arranged based on the expected pattern.

[0063] In practical applications, the etching process in this micro-machining process can be implemented in different ways such as wet etching or dry etching. The wet etching process can refer to a lift-off process, which mainly uses the chemical reaction of the solution to strip (or etch) the photoresist layer; while the dry etching process refers to a waterless stripping process that does not use a solution to strip the photoresist layer. In addition, what is different is that for the coating process (such as metal film) in micro-machining, the coating process is executed after the glue coating when the lift-off process is used, and before the glue coating when the dry etching process is used; for this reason, the same HOPG sample is processed through the lift-off process or the dry etching process, and the position and size of the graphite islands finally formed on the substrate are different relative to the HOPG sample as a whole. For details, please see the following text description, Figure 3 , Figure 4 .

[0064] 1. Lift-off process is used to remove the photoresist layer in micromachining

[0065] As a possible implementation mode, the above-mentioned micro-machining process may specifically include: coating, exposing and developing the sample flakes on the substrate so that the upper surface of the sample flakes shows the expected pattern not covered by the photoresist layer; coating the photoresist layer and the expected pattern, and using a lift-off process to peel off the photoresist layer to obtain a mask directly deposited on the upper surface and forming the expected pattern; etching the sample flakes according to the deposition position of the mask to obtain two-dimensional material islands arranged in the expected pattern.

[0066] Specifically, Figure 3 As shown, the HOPG flakes on the silicon wafer can be coated with glue (such as photoresist), exposed, and developed to obtain a photoresist pattern not covered by the photoresist layer; then, a metal film can be plated on the surface of the photoresist layer and the upper surface of the exposed HOPG flakes through electron beam evaporation or magnetron sputtering, and then the unnecessary photoresist can be dissolved away using a remover of the lift-off process to retain the required metal pattern mask; finally, the HOPG flakes can be etched using oxygen plasma with reference to the distribution position of the metal pattern mask to form pieces of graphite islands.

[0067] 2. Dry etching process is used to strip the photoresist layer in micromachining

[0068] As another possible implementation, the above-mentioned micro-machining process may specifically include: coating the sample flakes on the substrate to obtain a mask layer; coating, exposing and developing the mask layer so that the expected pattern covered by the photoresist layer appears above the sample flakes; dry etching the developed photoresist layer and the mask layer according to a preset etching selectivity to obtain two-dimensional material islands arranged according to the expected pattern; the etching selectivity refers to the etching rate ratio between the photoresist exposed above the sample flakes and the coating material under the same etching conditions.

[0069] Specifically, Figure 4 As shown, the HOPG flakes attached to the substrate can be coated (such as (metal film or other dielectric film), and the coating process can be specifically electron beam evaporation or magnetron sputtering process; then, the HOPG flakes can be coated, exposed, and developed to design the expected pattern covered by the photoresist layer, that is, surface patterning design is performed; using gas plasma such as oxygen or argon, the developed HOPG flakes are dry-etched to dissolve the top layer of material (because etching is from top to bottom), such as dissolving all the photoresist and the exposed part of the metal film on the top, and retaining the metal film originally covered and protected by the photoresist. Of course, in order to achieve such an ideal product effect with both deletion and retention, it is necessary to control the etching selectivity between the photoresist and the metal film, which is crucial for accurately controlling the size and shape of the graphite island forming pattern; the remaining metal film can be used as the graphite island cover, and finally, the metal island cover mask can be etched away to complete the preparation of the graphite island.

[0070] Exemplarily, the calculation formula of the above etching selectivity ratio can be recorded as: etching selectivity ratio = etching rate of masking layer material (such as photoresist) / etching rate of etched material (such as metal), such as Figure 3 As shown, selecting a low selectivity (i.e., the denominator is greater than the numerator) here means that during the etching process, the photoresist on the metal film is as small as possible, and the metal layer that is not covered and protected by the photoresist (i.e., exposed) is etched away as much as possible. Because etching is generally from top to bottom, the selectivity is small or even non-existent, so the etching selectivity in this formula can be between 1:5 and 1:10. Of course, in practical applications, the value of the above etching selectivity can be comprehensively determined according to the thickness, distribution size, etc. of the covered photoresist and metal film, and is not specifically limited.

[0071] In summary, the method of the embodiment of the present application can peel off a flat graphite sheet of ten microns or less. In addition, experiments have shown that this graphite sheet can obtain an extremely low friction coefficient in the friction and wear test with three-dimensional materials (spherical surfaces) and two-dimensional materials (graphite islands), and can maintain a high surface flatness and no defects during the transfer process; this graphite sheet and the substrate sheet can be in rigid contact and tightly adhered, which has a wide range of use value for the transfer of specific devices. In short, the method of the embodiment of the present application realizes the large-area, thin-layer, pollution-free, binder-free transfer of two-dimensional super-slippery materials (single-crystal graphite, molybdenum disulfide, etc.) on a flat substrate and close fit, providing a feasible reference solution for the high-quality transfer of super-slippery materials of ten microns or less in related devices.

[0072] Compared to Figure 1 The examples shown illustrate that the above-mentioned additional or detailed example contents or possible implementation methods do not necessarily have to be executed during the specific implementation. If more than two examples or possible implementation methods are added, these examples or possible implementation methods can be implemented in combination or separately. If implemented in combination, the execution order between the combined examples can be determined according to their respective processing logic, which can be determined according to the actual scenario.

[0073] The above embodiments are only used to illustrate the technical solution of the present application, but not to limit it.

Claims

1. A method for exfoliating an ultra-thin layer of two-dimensional material, characterized in that: include: Cleavage the two-dimensional material sheet at least once through a thermal release tape into a two-dimensional material sheet, wherein the thickness of the two-dimensional material sheet is 1 to 10 micrometers; The bonding surface of the base sheet is subjected to a surface roughening treatment; the bonding surface refers to the surface pre-bonded with the two-dimensional material sheet; Affixing the heat release tape with the two-dimensional material sheet attached to the base sheet, and the two-dimensional material sheet is attached to the adhesive surface to form a sample assembly; Placing the entire sample assembly in a vacuum environment, applying pressure, and maintaining the pressure for a preset time; The thermal release tape is heated to separate the thermal release tape from the two-dimensional material sheet, thereby obtaining a two-dimensional material sheet that is separately attached to the base sheet.

2. The method for exfoliating an ultra-thin layer of two-dimensional material according to claim 1, characterized in that: After the two-dimensional material plate is cleaved at least once into two-dimensional material flakes by the thermal release tape, before the thermal release tape with the two-dimensional material flakes attached to the base sheet is attached, the method further comprises: One of the main surfaces of the two-dimensional material sheet is etched to make the main surface clean and have a concave-convex structure; the main surface is parallel to the stacking direction of each material layer in the two-dimensional material sheet, and the main surface is pre-adhered to the thermal release tape and jointly attached to the base sheet.

3. The method for stripping an ultra-thin layer of two-dimensional material according to claim 2, characterized in that: The etching process on one of the main surfaces of the two-dimensional material sheet comprises: The two-dimensional material sheet is placed in a reactive ion etching (RIE) device to perform an etching treatment for a preset time on one of the main surfaces of the two-dimensional material sheet.

4. The method for stripping an ultra-thin layer of two-dimensional material according to claim 3, characterized in that: When the RIE equipment uses oxygen plasma for etching, the preset duration ranges from 1 to 3 minutes.

5. The method for exfoliating an ultra-thin layer of two-dimensional material according to claim 1 or 2, characterized in that: The environmental pressure of the pressure-maintaining treatment is below 10 Pa, and the preset time of the pressure-maintaining process is 1 to 2 hours.

6. The method for stripping an ultra-thin layer of two-dimensional material according to claim 1 or 2, characterized in that: The heating temperature is 100 to 200 degrees Celsius.

7. The method for exfoliating an ultra-thin layer of two-dimensional material according to claim 1 or 2, characterized in that: The surface roughening treatment is performed by plasma sputtering.

8. The method for stripping an ultra-thin layer of two-dimensional material according to claim 7, characterized in that: When the plasma sputtering process uses argon plasma to perform sputtering etching, the duration of the sputtering etching is comprised between 5 and 10 minutes.

9. The method for exfoliating an ultra-thin layer of two-dimensional material according to claim 1 or 2, characterized in that: The two-dimensional material plate adopts highly oriented pyrolytic graphite.

10. The method for exfoliating an ultra-thin layer of two-dimensional material according to claim 1 or 2, characterized in that: After obtaining the two-dimensional material sheet separately attached to the base sheet, the method further comprises: Performing film coating, gluing, exposure and development processing on the two-dimensional material sheet separately attached to the base sheet, so that the expected pattern appears on the two-dimensional material sheet; The material above the developed two-dimensional material slice is etched to obtain a two-dimensional material island arranged based on the expected pattern.

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