A method of preparing a patterned monolayer two-dimensional material

Abstract

The embodiment of the present application provides a kind of to two-dimensional atomic crystal material transfer technical field, with a kind of preparation patterned monolayer two-dimensional material method, the method comprises: preparation upper surface has multiple PDMS protrusions patterned PDMS stamp, and make multiple PDMS protrusions with preset pattern style arrangement;Continuous monolayer two-dimensional TMDs film is grown on film substrate;The monolayer two-dimensional TMDs film is transferred to the upper surface of the PDMS protrusion, and patterned monolayer two-dimensional TMDs film is obtained;The patterned monolayer two-dimensional TMDs film is transferred to target substrate, and patterned monolayer two-dimensional material is obtained.The patterned monolayer two-dimensional material is transferred by the method, and the problems that two-dimensional material patterning and two-dimensional material transfer process in prior art are complex, cost is high, time-consuming long are solved.

Description

TECHNICAL FIELD

[0001] The embodiment of the present application relates to the technical field of two-dimensional material transfer, in particular to a method for preparing a patterned single-layer two-dimensional material BACKGROUND

[0002] Two-dimensional atomic crystal material, i.e. two-dimensional material, is widely studied in the field of microelectronic devices due to its unique structure and physical properties. At present, mechanical exfoliation method and chemical vapor deposition (CVD) method are main methods for obtaining two-dimensional material. However, in the process of constructing new two-dimensional electronic devices, a transfer step is generally needed to transfer the grown two-dimensional material to a new target substrate (such as SiO2 / Si substrate, flexible PET substrate, etc.) to realize compatibility with silicon semiconductor process or realize the preparation of flexible electronic devices.

[0003] Using a two-dimensional material transfer platform, positioning and transferring different two-dimensional materials is a common method for laboratory to develop prototype devices and characterize properties at present. In order to obtain high-density integration of two-dimensional electronic devices, the transferred two-dimensional material often needs subsequent micro-processing steps such as spin-coating photoresist, optical exposure, development, reactive ion etching (RIE), and photoresist removal, to realize the patterning of two-dimensional material.

[0004] In the process of implementing the present application, the applicant found that there are at least the following problems in the prior art: the process is complex, the cost is high, and the time is long in the process of preparing a patterned single-layer two-dimensional material. SUMMARY

[0005] In order to solve the problems of complex process, high cost and long time in the process of preparing a patterned single-layer two-dimensional material, the embodiment of the present application provides a method for preparing a patterned single-layer two-dimensional material.

[0006] The method comprises:

[0007] Preparation of a patterned PDMS stamp with a plurality of PDMS protrusions on the upper surface, and the plurality of PDMS protrusions are arranged in a preset pattern;

[0008] Growth of a continuous single-layer two-dimensional TMDs film on a thin film substrate;

[0009] Transferring the single-layer two-dimensional TMDs film to the upper surface of the PDMS protrusion to obtain a patterned single-layer two-dimensional TMDs film;

[0010] Transferring the patterned single-layer two-dimensional TMDs film to a target substrate to obtain a patterned single-layer two-dimensional material.

[0011] The technical scheme has the following beneficial effects: the method for transferring the patterned two-dimensional material by using the technical means of the patterned PDMS stamp and the surface tension of water achieves the technical effects of simple operation, cost saving and high efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0013] Figure 1 is a flowchart of a method for preparing a single-layer two-dimensional material array according to an embodiment of the present application;

[0014] Figure 2 is a schematic diagram of a PDMS stamp structure according to an embodiment of the present application;

[0015] Figure 3 is a schematic diagram of a thin film substrate and a single-layer two-dimensional TMDs thin film according to an embodiment of the present application;

[0016] Figure 4 is a schematic diagram of adding water from the edge of the PDMS stamp to the thin film substrate according to an embodiment of the present application;

[0017] Figure 5 is a schematic diagram of transferring a single-layer two-dimensional TMDs to the upper surface of the PDMS protrusion according to an embodiment of the present application;

[0018] Figure 6 is a schematic diagram of transferring the patterned single-layer two-dimensional TMDs thin film to a target substrate according to an embodiment of the present application;

[0019] Figure 7 is a schematic diagram of transferring the patterned single-layer two-dimensional TMDs thin film to a target substrate according to an embodiment of the present application;

[0020] Figure 8 is a magnified picture of the patterned PDMS stamp under an optical microscope according to an embodiment of the present application;

[0021] Figure 9a is a partial magnified picture of the patterned PDMS stamp under an optical microscope according to an embodiment of the present application;

[0022] Figure 9b is another partial magnified picture of the patterned PDMS stamp under an optical microscope according to an embodiment of the present application

[0023] Figure 10ais a partial enlarged picture of the single-layer two-dimensional TMDs film transferred to the upper surface of the PDMS protrusion under an optical microscope according to an embodiment of the present application;

[0024] Figure 10b is another partial enlarged picture of the single-layer two-dimensional TMDs film transferred to the upper surface of the PDMS protrusion under an optical microscope according to an embodiment of the present application;

[0025] Figure 11a is a picture of the patterned two-dimensional TMDs material obtained on the target substrate under an optical microscope with 100 times magnification when the PDMS protrusion is 10 μm x 10 μm and the protrusion spacing is 30 μm according to an embodiment of the present application;

[0026] Figure 11b is a picture of the patterned two-dimensional TMDs material obtained on the target substrate under an optical microscope with 200 times magnification when the PDMS protrusion is 10 μm x 10 μm and the protrusion spacing is 30 μm according to an embodiment of the present application;

[0027] Figure 11c is a picture of the patterned two-dimensional TMDs material obtained on the target substrate under an optical microscope with 500 times magnification when the PDMS protrusion is 10 μm x 10 μm and the protrusion spacing is 30 μm according to an embodiment of the present application;

[0028] Figure 11d is a picture of the patterned two-dimensional TMDs material obtained on the target substrate under an optical microscope with 1000 times magnification when the PDMS protrusion is 10 μm x 10 μm and the protrusion spacing is 30 μm according to an embodiment of the present application;

[0029] Figure 12a is a picture of the patterned two-dimensional TMDs material obtained on the target substrate under an optical microscope with 200 times magnification when the PDMS protrusion is 20 μm x 20 μm and the protrusion spacing is 20 μm according to an embodiment of the present application;

[0030] Figure 12b is a picture of the patterned two-dimensional TMDs material obtained on the target substrate under an optical microscope with 500 times magnification when the PDMS protrusion is 20 μm x 20 μm and the protrusion spacing is 20 μm according to an embodiment of the present application

[0031] The reference signs are as follows:

[0032] 01, PDMS stamp; 02, film substrate; 03, single-layer two-dimensional TMDs film; 04, rubber-tipped dropper; 05, water; 06, target substrate; 07, patterned single-layer two-dimensional TMDs film. DETAILED DESCRIPTION

[0033] With reference to the accompanying drawings, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative work are within the protection scope of the present application.

[0034] The technical solutions of the above-described embodiments of the present application will be described in detail below in combination with specific application examples. Technical details not introduced in the implementation process can be referred to the related descriptions in the foregoing.

[0035] Two-dimensional atomic crystal materials have been widely studied in the field of microelectronic devices due to their unique structure and physical properties. The unique structure and properties of two-dimensional materials, such as no dangling bonds on the material surface, monocrystalline atomic layer thickness, and van der Waals force between layers, contain rich new physics and novel effects. In particular, two-dimensional TMDs materials represented by MoS2, WSe2, WS2, and MoSe2 have semiconductor characteristics, suitable band gap, high carrier mobility, and long-term stability at room temperature, which make it possible to develop new electronic devices.

[0036] At present, mechanical exfoliation and chemical vapor deposition (CVD) are the main methods to obtain two-dimensional materials. With the deepening of research and the improvement of growth process, CVD has initially realized the preparation of wafer-scale continuous thin films of two-dimensional materials (MoS2, h-BN, WSe2, etc.). These methods have solved the problem of small lateral size and uncontrollable layer number of samples prepared by traditional mechanical exfoliation method to some extent. Controllable preparation of large-area and high-quality two-dimensional materials is the premise of obtaining high-performance two-dimensional electronic devices and realizing array integration. However, in the process of constructing new two-dimensional electronic devices, it is generally necessary to transfer the grown two-dimensional materials to a new target substrate (such as SiO2 / Si substrate, flexible PET substrate, etc.) to realize compatibility with silicon semiconductor process or realize the preparation of flexible electronic devices.

[0037] Using a two-dimensional material transfer platform, positioning and transferring different two-dimensional materials is a common method for prototype device development and property characterization in laboratories at this stage. Common transfer methods include dry transfer and wet transfer, and common transfer media are generally flexible organic polymers such as PMMA, PDMS, PS, PVA, etc. Based on the positioning and transferring method, micron (μm) to centimeter (cm) two-dimensional material transfer has been realized. However, in order to obtain high-density integration of two-dimensional electronic devices, the transferred two-dimensional material often needs subsequent spin-on photoresist, optical exposure, development, reactive ion etching (RIE), and de-gluing micro-processing steps to achieve two-dimensional material patterning. The above micro-processing steps have the disadvantages of complex process, high cost, long time-consuming, and easy to introduce impurity particles on the material surface. If a new transfer technology can be developed to realize large-area transfer and material patterning in one step, it will help to further expand the application range of two-dimensional electronic devices and improve the device preparation efficiency.

[0038] The embodiment of the present application utilizes a patterned PDMS stamp to realize the method for preparing a patterned two-dimensional material. In the traditional mass transfer micro-LED technology, the growth substrate needs to be etched by a chemical solution (HF, NaOH) to obtain a suspended structure, and the thickness of the transferred light-emitting diode (GaN) is above several hundred nanometers. The method for preparing a patterned two-dimensional TMDs material of the embodiment of the present application can realize the separation of the two-dimensional TMDs material and the growth substrate only by using the surface tension of water. In addition, the thickness of the transferred two-dimensional material is below 1 nanometer, and the method has the advantages of simple operation, repeatability, and high efficiency. The method provides a basis for the preparation of a high-density two-dimensional TMDs material array and device integration.

[0039] As shown in Figure 1 , the method for preparing a patterned single-layer two-dimensional material comprises:

[0040] S1, preparing a patterned PDMS stamp 01 with a plurality of PDMS protrusions on the upper surface, and arranging the plurality of PDMS protrusions in a preset pattern;

[0041] S2, growing a continuous single-layer two-dimensional TMDs film 03 on a thin film substrate 02;

[0042] S3, transferring the single-layer two-dimensional TMDs film 03 to the upper surface of the PDMS protrusion to obtain a patterned single-layer two-dimensional TMDs film 07;

[0043] S4, transferring the patterned single-layer two-dimensional TMDs film 07 to a target substrate 06 to obtain a patterned single-layer two-dimensional material.

[0044] The embodiment of the present application obtains a patterned single-layer two-dimensional material by transferring the patterned PDMS stamp 01. PDMS represents polydimethylsilane, which is a kind of organic silicon and has good adhesion with a silicon wafer. Due to the good adhesion between PDMS and the silicon wafer, the PDMS stamp 01 can be used to conveniently realize the transfer of the two-dimensional material. According to requirements, a patterned mold is selected. Since PDMS is a viscous liquid material, the PDMS is spin-coated in the patterned mold. After processing, the patterned PDMS stamp 01 with a plurality of PDMS protrusions on the upper surface is obtained, as shown in Figure 2 As shown in Figure 8 The patterned PDMS stamp 01 under an optical microscope contains regularly and orderly arranged PDMS protrusions, wherein Figure 8 The scale is 40 μm. Generally, the size of the PDMS protrusion is between 10 μm and 50 μm, and the interval is between 10 μm and 50 μm, as shown in Figure 11a to Figure 11d The size of the PDMS protrusion is 10 μm x 10 μm, and the protrusion interval is 30 μm, as shown in Figure 12a , Figure 12b The size of the PDMS protrusion is 20 μm x 20 μm, and the protrusion interval is 20 μm.

[0045] As shown in Figure 9a , as shown in Figure 9b The patterned PDMS stamp under an optical microscope is a partial enlarged view, wherein Figure 9a The scale is 30 μm, Figure 9b The scale is 10 μm.

[0046] The PDMS protrusion can be a cylindrical structure or other regular polygonal structure. The embodiment of the present application adopts the cuboid structure of the PDMS protrusion, as shown in Figure 2 The PDMS stamp 01 is fixed at the middle position of the glass slide, so that the PDMS stamp 01 can be conveniently operated. The number of the PDMS protrusions, the arrangement mode and the shape of the upper surface are determined by the patterned mold, for example, the array of regularly arranged cuboids.

[0047] After the PDMS stamp 01 is prepared, the two-dimensional material needs to be obtained, so that the two-dimensional material is transferred to the target position by the PDMS stamp 01. Generally, the two-dimensional material can be obtained by generating a two-dimensional material film. The two-dimensional TMDs material represented by MoS2, WSe2, WS2 and MoSe2, wherein TMDs represents a transition metal chalcogenide, has become an important material for developing new electronic devices due to the semiconductor characteristics, suitable band gap, high carrier mobility and long-term stability at room temperature. Therefore, the two-dimensional material transferred by the embodiment of the present application is taken as an example to be explained.

[0048] As shown inFigure 3 As shown, a thin film substrate 02 for generating a two-dimensional material thin film is selected, the thin film substrate 02 is a single crystal sapphire substrate containing a silicon dioxide layer or polished, a continuous monolayer two-dimensional TMDs thin film is generated on the thin film substrate 02.

[0049] After generating the monolayer two-dimensional TMDs thin film 03, since the film is continuous, in order to obtain a patterned two-dimensional TMDs material, the PDMS stamp 01 is used to paste the monolayer two-dimensional TMDs material on the upper surface of the PDMS protrusion, so that the upper surface of the PDMS protrusion covers the monolayer two-dimensional TMDs thin film. Since the PDMS protrusion is generated according to the demand using a patterned mold, the upper surface of the PDMS protrusion is a preset pattern, and the arrangement of the PDMS protrusion is also a preset arrangement, so that the monolayer two-dimensional TMDs material covered by the upper surface of the PDMS protrusion forms a patterned monolayer two-dimensional TMDs thin film 07 with the same arrangement as the PDMS protrusion and the same shape and size as the upper surface of the PDMS.

[0050] After the patterned monolayer two-dimensional TMDs thin film 07 is covered on the PDMS protrusion, it is necessary to separate the patterned monolayer two-dimensional TMDs thin film 07 from the PDMS protrusion and place it on the target substrate 06, that is, to transfer the patterned monolayer two-dimensional TMDs thin film 07 to the target substrate 06 through the PDMS stamp 01, and finally obtain a patterned monolayer two-dimensional TMDs material on the target substrate 06. At this time, the patterned monolayer two-dimensional TMDs material on the target substrate 06 can be used for related research and production in the microelectronics field. Two-dimensional TMDs material is part of two-dimensional material, and two-dimensional TMDs material is the most commonly used and researched two-dimensional material. Therefore, the embodiment of the present application realizes the preparation of patterned monolayer two-dimensional material by patterning the monolayer two-dimensional TMDs material. The patterning not only realizes the patterning of a single monolayer two-dimensional material through the shape of the upper surface of the PDMS protrusion, but also realizes the change of the monolayer two-dimensional material from a continuous monolayer two-dimensional material to a patterned arrangement in a preset arrangement style through different arrangement modes of the PDMS protrusion.

[0051] Further, a patterned PDMS stamp 01 with a plurality of PDMS protrusions on the upper surface is prepared, and the plurality of PDMS protrusions are arranged in a preset manner, comprising:

[0052] designing a patterned mold;

[0053] filling the patterned mold with PDMS by spin coating process;

[0054] curing the PDMS in the patterned mold;

[0055] The cured PDMS is demolded from the patterned mold to obtain the patterned PDMS stamp 01.

[0056] The PDMS stamp 01 is obtained through a patterned mold, such as an SU-8 patterned mold. The mold is designed to meet specific requirements (e.g., pattern shape, arrangement, size). PDMS is spin-coated into the patterned mold. Under centrifugal force, the mold is filled with PDMS, resulting in a smooth and even surface. Since PDMS is a viscous liquid, it needs to be cured after filling the mold. After curing, the PDMS is demolded from the patterned mold, ultimately yielding the patterned PDMS stamp 01. The PDMS protrusions on the stamp 01 have a preset pattern and arrangement. The upper surface of the PDMS protrusions is smooth, even, and has a certain degree of adhesion. In this embodiment of the invention... Figure 1 The dimensions (length * width) of the PDMS stamp 01 shown are 3mm * 3mm, the dimensions (length * width * height) of the PDMS protrusions on the PDMS are 10μm × 10μm × 15μm, and the spacing between the PDMS protrusions is 30μm.

[0057] Furthermore, such as Figure 4 , Figure 5 As shown, the step of transferring the single-layer two-dimensional TMDs film 03 onto the upper surface of the PDMS protrusion to obtain a patterned single-layer two-dimensional TMDs film 07 includes:

[0058] Invert the PDMS stamp 01 so that the PDMS protrusion of the PDMS stamp 01 is bonded to the single-layer two-dimensional TMDs film 03.

[0059] Separate the single-layer two-dimensional TMDs film 03, which is attached to the PDMS protrusion, from the film substrate 02;

[0060] The portion that contacts the upper surface of the PDMS protrusion

[0061] The single-layer two-dimensional TMDs film 03 is peeled off to obtain a patterned single-layer two-dimensional TMDs film 07.

[0062] The PDMS stamp 01 is inverted, and the upper surface of the PDMS protrusion is in contact with the film substrate 02. Under the action of external pressure, the upper surface of the PDMS protrusion is pasted with the monolayer two-dimensional TMDs material film (such as a monolayer MoS2 film) on the film substrate 02. Water is used to separate the monolayer two-dimensional TMDs film 03 originally attached to the film substrate 02 from the film substrate 02. Because the upper surface of the PDMS protrusion has been pasted on the monolayer two-dimensional TMDs film 03, after the monolayer two-dimensional TMDs film 03 is separated from the film substrate 02, the PDMS stamp 01 is slowly lifted. The part of the monolayer two-dimensional TMDs film 03 pasted on the upper surface of the PDMS protrusion is separated from the monolayer two-dimensional TMDs film 03 outside the upper surface of the PDMS protrusion as the PDMS stamp 01 is lifted. In this way, a patterned monolayer two-dimensional TMDs film 07 is obtained, as shown in FIG. 3. Because the PDMS protrusions in the PDMS stamp 01 are periodically and regularly arranged, the continuous monolayer two-dimensional TMDs film 03 is converted into a TMDs array that is periodically and regularly arranged. The size of the patterned monolayer two-dimensional TMDs film is consistent with the size of the PDMS protrusion. Figure 5 Further, the separation of the monolayer two-dimensional TMDs film 03 pasted on the PDMS protrusion from the film substrate 02 includes: dripping water 05 from the side of the PDMS stamp 01 to the film substrate 02, so as to separate the monolayer two-dimensional TMDs film 03 from the film substrate 02.

[0063] Further, the separation of the monolayer two-dimensional TMDs film 03 pasted on the PDMS protrusion from the film substrate 02 includes: dripping water 05 from the side of the PDMS stamp 01 to the film substrate 02, so as to separate the monolayer two-dimensional TMDs film 03 from the film substrate 02.

[0064] As shown in FIG. 4, a few drops of water 05 are dripped from the edge of the side of the PDMS stamp 01 to the film substrate 02 by using a tool such as a rubber-headed dropper 04. Under the action of the surface tension of the water 05, the water 05 penetrates into the interface between the monolayer two-dimensional TMDs film 03 and the film substrate 02, and promotes the separation of the monolayer two-dimensional TMDs film 03 from the film substrate 02. Figure 4

[0065] Further, the transfer of the patterned monolayer two-dimensional TMDs film 07 to a target substrate 06 to obtain a patterned monolayer two-dimensional material includes:

[0066] The PDMS protrusion pasted with the patterned monolayer two-dimensional TMDs film 07 is in contact with the target substrate 06, so as to paste the patterned monolayer two-dimensional TMDs film 07 to the target substrate 06.

[0067] The PDMS stamp 01 is separated from the patterned monolayer two-dimensional TMDs film 07, so as to transfer the patterned monolayer two-dimensional TMDs film 07 to the target substrate 06 to obtain a patterned monolayer two-dimensional material.

[0068] As shown in FIG. 5, the PDMS stamp 01 is separated from the patterned monolayer two-dimensional TMDs film 07, so as to transfer the patterned monolayer two-dimensional TMDs film 07 to the target substrate 06 to obtain a patterned monolayer two-dimensional material.​Figure 6 As shown in FIG. 1, a PDMS stamp 01 with a patterned monolayer two-dimensional TMDs film 07 is inverted, and the inverted PDMS stamp 01 is in contact with a target substrate 06. Then, an external force is applied to the PDMS stamp 01. Under the action of the external force, the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is attached to the target substrate 06. Then, the PDMS stamp 01 is slowly lifted, and the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is separated from the PDMS protrusion. Figure 5 As shown in FIG. 1, a PDMS stamp 01 with a patterned monolayer two-dimensional TMDs film 07 is inverted, and the inverted PDMS stamp 01 is in contact with a target substrate 06. Then, an external force is applied to the PDMS stamp 01. Under the action of the external force, the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is attached to the target substrate 06. Then, the PDMS stamp 01 is slowly lifted, and the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is separated from the PDMS protrusion. Figure 10a As shown in FIG. 1, a PDMS stamp 01 with a patterned monolayer two-dimensional TMDs film 07 is inverted, and the inverted PDMS stamp 01 is in contact with a target substrate 06. Then, an external force is applied to the PDMS stamp 01. Under the action of the external force, the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is attached to the target substrate 06. Then, the PDMS stamp 01 is slowly lifted, and the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is separated from the PDMS protrusion. Figure 10b As shown in FIG. 1, a PDMS stamp 01 with a patterned monolayer two-dimensional TMDs film 07 is inverted, and the inverted PDMS stamp 01 is in contact with a target substrate 06. Then, an external force is applied to the PDMS stamp 01. Under the action of the external force, the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is attached to the target substrate 06. Then, the PDMS stamp 01 is slowly lifted, and the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is separated from the PDMS protrusion. Figure 10a The scale of FIG. 1 is 30 μm. Figure 10b The scale of FIG. 1 is 10 μm.

[0069] As shown in FIG. 1, a PDMS stamp 01 with a patterned monolayer two-dimensional TMDs film 07 is inverted, and the inverted PDMS stamp 01 is in contact with a target substrate 06. Then, an external force is applied to the PDMS stamp 01. Under the action of the external force, the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is attached to the target substrate 06. Then, the PDMS stamp 01 is slowly lifted, and the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is separated from the PDMS protrusion. Figure 11a to Figure 11d As shown in FIG. 1, a PDMS stamp 01 with a patterned monolayer two-dimensional TMDs film 07 is inverted, and the inverted PDMS stamp 01 is in contact with a target substrate 06. Then, an external force is applied to the PDMS stamp 01. Under the action of the external force, the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is attached to the target substrate 06. Then, the PDMS stamp 01 is slowly lifted, and the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is separated from the PDMS protrusion. Figure 11a Figure 11b Figure 11c Figure 11d As shown in FIG. 1, a PDMS stamp 01 with a patterned monolayer two-dimensional TMDs film 07 is inverted, and the inverted PDMS stamp 01 is in contact with a target substrate 06. Then, an external force is applied to the PDMS stamp 01. Under the action of the external force, the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is attached to the target substrate 06. Then, the PDMS stamp 01 is slowly lifted, and the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is separated from the PDMS protrusion. Figure 11a The scale of FIG. 1 is 100 μm. Figure 11b The scale of FIG. 1 is 40 μm. Figure 11c The scale of FIG. 1 is 20 μm. Figure 11d The scale of FIG. 1 is 10 μm.

[0070] As shown in FIG. 1, a PDMS stamp 01 with a patterned monolayer two-dimensional TMDs film 07 is inverted, and the inverted PDMS stamp 01 is in contact with a target substrate 06. Then, an external force is applied to the PDMS stamp 01. Under the action of the external force, the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is attached to the target substrate 06. Then, the PDMS stamp 01 is slowly lifted, and the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is separated from the PDMS protrusion. Figure 12a Figure 12b As shown in FIG. 1, a PDMS stamp 01 with a patterned monolayer two-dimensional TMDs film 07 is inverted, and the inverted PDMS stamp 01 is in contact with a target substrate 06. Then, an external force is applied to the PDMS stamp 01. Under the action of the external force, the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is attached to the target substrate 06. Then, the PDMS stamp 01 is slowly lifted, and the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is separated from the PDMS protrusion.

[0071] Further, the film substrate 02 includes a silicon substrate containing a silicon dioxide layer or a polished single crystal sapphire substrate. As shown in FIG. 1, a PDMS stamp 01 with a patterned monolayer two-dimensional TMDs film 07 is inverted, and the inverted PDMS stamp 01 is in contact with a target substrate 06. Then, an external force is applied to the PDMS stamp 01. Under the action of the external force, the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is attached to the target substrate 06. Then, the PDMS stamp 01 is slowly lifted, and the patterned monolayer two-dimensional TMDs film 07 on the upper surface of the PDMS protrusion is separated from the PDMS protrusion. Figure 3 ​​​​The thin film substrate 02 shown is a 1cm x 1cm silicon substrate containing a silicon dioxide layer, wherein the thickness of the silicon dioxide layer is about 300nm.

[0072] Further, the target substrate 06 comprises: a silicon substrate containing a silicon dioxide layer, a glass substrate, a flexible polyimide or a flexible polyethylene terephthalate substrate. As shown Figure 6 The target substrate 06 shown is a 1cm x 1cm silicon substrate containing a silicon dioxide layer, wherein the thickness of the silicon dioxide layer is about 300nm, and the glass substrate, the flexible polyimide or the flexible polyethylene terephthalate can also be used as the substrate.

[0073] Further, the continuous monolayer two-dimensional TMDs film 03 is generated on the thin film substrate 02, and is realized by using a chemical vapor deposition method.

[0074] At present, the main methods for obtaining two-dimensional materials are mechanical exfoliation and chemical vapor deposition (CVD) method. With the deepening of research and the improvement of growth process, the CVD method has preliminarily realized the preparation of wafer-level continuous two-dimensional material film, and to some extent, solved the problems of small lateral size and difficult control of the number of layers in the traditional mechanical exfoliation method. Therefore, in the embodiment of the present application, the CVD method is used to generate a monolayer two-dimensional TMDs film 03, wherein the selected TMDs film is a monolayer, continuous molybdenum disulfide (MoS2) film, and the monolayer, continuous MoS2 film is uniformly distributed on the thin film substrate 02.

[0075] Further, the area of the thin film substrate 02 is not less than the area of the PDMS stamp 01.

[0076] Since the PDMS protrusions on the PDMS stamp 01 are the carriers for preparing and transferring the patterned monolayer two-dimensional TMDs film 07, if the area of the thin film substrate 02 is less than that of the PDMS stamp, the protrusions in the PDMS stamp 01 cannot be completely covered by the monolayer two-dimensional TMDs film 03, and finally the patterned monolayer two-dimensional TMDs film 07 in the preset arrangement cannot be obtained.

[0077] Further, the area of the target substrate 06 is not less than the area of the PDMS stamp 01.

[0078] The continuous monolayer two-dimensional TMDs film generated by the CVD method is pasted on the upper surface of the PDMS protrusion by using the adhesion of the upper surface of the PDMS protrusion in the PDMS stamp 01, and then is transferred to the target substrate 06 by the PDMS stamp 01. If the area of the target substrate 06 is less than that of the PDMS stamp 01, only part of the PDMS protrusions can contact the target substrate 06, so that only part of the patterned monolayer two-dimensional TMDs film 07 can be transferred, and the patterned two-dimensional material in the preset arrangement cannot be obtained on the target substrate 06.

[0079] The embodiment of the present application adopts the principle of interaction between the stamp and the ink pad, and under the tension effect of the water surface, the two-dimensional material is transferred from one carrier to another carrier, and patterning is realized in the process, and finally the patterned two-dimensional material is obtained. The embodiment of the present application is simple to operate, does not need to use special materials, saves preparation cost, and can quickly and efficiently obtain the patterned two-dimensional material by using the method of the embodiment of the present application.

[0080] It should be understood that the specific order or hierarchy of steps in the processes disclosed is an example of illustrative approaches. Based upon design preferences, it should be understood that the specific order or hierarchy of steps in the processes can be re-arranged while remaining within the scope of the present disclosure. The accompanying method claims present elements of the various steps in a sample order, and are not meant to be limited to the specific order or hierarchy presented.

[0081] In the above detailed description, various features are grouped together in single embodiments for the purpose of streamlining the disclosure. Such disclosed approaches should not be interpreted as reflecting an intention that the claimed embodiments require more features than are explicitly recited in each claim. On the contrary, as indicated above, the inventiveness resides in less, the claimed subject matter than in the disclosed single embodiments. Accordingly, the claims are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate preferred embodiment.

[0082] In order for any person skilled in the art to implement or use the present application, the above discloses the disclosed embodiments. For those skilled in the art, various modifications of these embodiments are obvious, and the general principles defined herein can also be applied to other embodiments without departing from the spirit and protection scope of the present disclosure. Therefore, the present disclosure is not limited to the embodiments given herein, but is consistent with the broadest scope of the principles and novel features disclosed in the present disclosure.

[0083] The above description includes examples of one or more embodiments. Of course, describing all possible combinations of components or methods for describing the above embodiments is not possible, but those of ordinary skill in the art should recognize that various embodiments can be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations falling within the scope of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the scope of the term is similar to the term "including", as explained in the claims as a conjunction word. In addition, the use of any one term "or" in the specification or claims is to mean "non-exclusive or".

[0084] The above detailed description of the specific embodiments of the present application is provided for the purpose of further explaining the objects, technical solutions and advantages of the present application, and it should be understood that the above description is only a specific embodiment of the present application and is not used to limit the protection scope of the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for preparing patterned single-layer two-dimensional materials, characterized in that, The method includes: A patterned PDMS stamp with multiple PDMS protrusions on its upper surface is prepared, and the multiple PDMS protrusions are arranged in a preset pattern. A continuous monolayer two-dimensional TMD thin film is grown on a thin film substrate; The single-layer two-dimensional TMDs film is transferred onto the upper surface of the PDMS protrusion to obtain a patterned single-layer two-dimensional TMDs film. The patterned monolayer two-dimensional TMDs thin film is transferred onto the target substrate to obtain a patterned monolayer two-dimensional material; Preparing a patterned PDMS stamp with multiple PDMS protrusions on its upper surface, and arranging the multiple PDMS protrusions in a preset pattern, includes: Design patterned molds; The patterned mold is filled with PDMS using a spin coating process; The PDMS within the patterned mold is cured. The cured PDMS is demolded from the patterned mold to obtain a patterned PDMS stamp; Among them, the size of the PDMS raised bumps in the patterned PDMS stamp is between 10 and 50 μm, and the spacing is between 10 and 50 μm. The step of transferring the single-layer two-dimensional TMDs film onto the upper surface of the PDMS protrusion to obtain a patterned single-layer two-dimensional TMDs film includes: The PDMS stamp is inverted so that the PDMS protrusion of the PDMS stamp is adhered to the single-layer two-dimensional TMDs film; Separate the single-layer two-dimensional TMDs film bonded to the PDMS protrusion from the film substrate; The single-layer two-dimensional TMDs film outside the contact portion with the upper surface of the PDMS protrusion is peeled off to obtain a patterned single-layer two-dimensional TMDs film. The separation of the single-layer two-dimensional TMDs film bonded to the PDMS protrusion from the film substrate includes: Water is dripped onto the thin film substrate from the side of the PDMS stamp to separate the monolayer two-dimensional TMDs film from the thin film substrate. The thickness of the single-layer two-dimensional TMDs film is less than 1 nanometer.

2. The method for preparing patterned single-layer two-dimensional materials as described in claim 1, characterized in that, The process of transferring the patterned monolayer two-dimensional TMDs thin film onto a target substrate to obtain a patterned monolayer two-dimensional material includes: The PDMS protrusions with the patterned monolayer two-dimensional TMDs film attached are brought into contact with the target substrate, so that the patterned monolayer two-dimensional TMDs film is attached to the target substrate. The PDMS stamp is separated from the patterned monolayer two-dimensional TMDs film, so that the patterned monolayer two-dimensional TMDs film is transferred onto the target substrate to obtain a patterned monolayer two-dimensional material.

3. The method for preparing patterned single-layer two-dimensional materials as described in claim 1, characterized in that, The thin film substrate includes a silicon substrate containing a silicon dioxide layer or a polished single-crystal sapphire substrate.

4. The method for preparing patterned single-layer two-dimensional materials as described in claim 1, characterized in that, The target substrate comprises: a silicon substrate containing a silicon dioxide layer, a glass substrate, and a flexible polyimide or flexible polyethylene terephthalate substrate.

5. The method for preparing patterned single-layer two-dimensional materials as described in claim 1, characterized in that, A continuous monolayer two-dimensional TMD thin film was formed on a thin film substrate using chemical vapor deposition.

6. The method for preparing patterned single-layer two-dimensional materials as described in claim 1, characterized in that, The area of ​​the thin film substrate is not less than the area of ​​the PDMS stamp.

7. The method for preparing patterned single-layer two-dimensional materials as described in claim 1, characterized in that, The area of ​​the target substrate is not less than the area of ​​the PDMS stamp.

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