Growth method of gallium nitride thin film and quasi Van der Waals epitaxial gallium nitride thin film

Abstract

The invention provides a gallium nitride thin film and a growth method of a quasi Van der Waals epitaxial gallium nitride thin film. The method comprises the following steps: step 101, transferring or directly growing on a substrate to obtain a two-dimensional material layer; step 102, processing the two-dimensional material layer by adopting a plasma enhanced MOCVD (Metal Organic Chemical Vapor Deposition) method; and step 103, performing quasi Van der Waals epitaxial growth of gallium nitride on the processed two-dimensional material layer to form the gallium nitride single crystal film. The invention also provides the gallium nitride film prepared by the method. According to the method provided by the invention, the quasi van der Waals epitaxy is carried out by using the plasma enhanced MOCVD, and plasma treatment and epitaxial growth can be completed in situ. Compared with MBE equipment, the method has the characteristics of high growth speed and large growth quantity in quasi Van der Waals epitaxy; compared with traditional MOCVD, the possibility that the two-dimensional material is polluted in the substrate transfer process can be reduced, and the crystal growth quality is improved.

Description

Technical Field

[0001] The invention relates to a gallium nitride film and a growth method of a quasi-van der Waals epitaxial gallium nitride film, belonging to the technical field of semiconductor materials and devices. Background Art

[0002] In recent years, the integration of two-dimensional materials and traditional semiconductors in device applications has attracted increasing attention. Two-dimensional materials include many types, such as graphene, h-boron nitride, and transition metal sulfides. The special properties of two-dimensional materials can be used to improve the performance of three-dimensional material devices. Among the many two-dimensional materials, graphene has attracted much attention due to its good conductivity, excellent mechanical strength, optical transparency, and large-scale production. In recent years, there is a heteroepitaxial technology called quasi-van der Waals epitaxy (QVDWE). This epitaxial technology can realize flexible and transferable semiconductor devices, which has not only become a frontier hot area in materials science, but also has practical industrial application value. In theory, the weak van der Waals force at the QVDWE interface can alleviate the strain caused by lattice mismatch and reduce dislocation density. When using graphene as an intermediate layer, the epitaxial layer is not connected to the substrate by covalent bonds, which reduces the lattice mismatch and thermal mismatch problems. More importantly, there is only a weak van der Waals force on the surface of the two-dimensional material, which makes mechanical exfoliation possible, and mechanical exfoliation can easily release the epitaxial layer from the substrate. In this way, the epitaxial layer can be transferred to any other substrate for subsequent device manufacturing, which reduces costs in a sense.

[0003] In van der Waals epitaxy, the epitaxial structure and the substrate are bonded by van der Waals forces, which is different from traditional epitaxy, where chemical bonds are formed between the film and the substrate. However, the strength of van der Waals forces is usually one to two orders of magnitude lower than the strength of chemical bonds. Therefore, it is difficult to achieve highly oriented nucleation and growth of nitride single crystals on graphene through van der Waals forces. The crystal quality of nitride films grown on graphene using van der Waals epitaxy is not as good as expected.

[0004] Quasi-van der Waals epitaxy introduces a small number of covalent bonds at the interface based on van der Waals epitaxy. This epitaxy method uses defects on the graphene surface to provide unsaturated dangling bonds as nucleation sites to induce highly oriented nucleation of gallium nitride. The arranged nucleation islands expand and merge to form a single-crystalline gallium nitride film. In this case, the epitaxial film is coupled to the graphene layer through a combination of covalent bonds and van der Waals forces. The covalent bond determines the epitaxial relationship between the epitaxial layer above and the graphene. In quasi-van der Waals epitaxy technology, graphene needs to be specially treated or even destroyed, and this process usually requires the participation of plasma. Generally speaking, MBE in the equipment for growing gallium nitride can achieve this process, but the MBE growth rate is extremely slow, and only a small amount is grown at a time, which cannot meet the actual industrial production requirements. Another MOCVD device generally does not have plasma, which means that other equipment is needed to process the two-dimensional material on the substrate. A single MOCVD cannot complete quasi-van der Waals epitaxy, which increases the cost of the equipment. In addition, new impurities will be introduced during the transfer process of the substrate, affecting the subsequent gallium nitride crystal quality. The quality of the transfer needs to be ensured, which increases the complexity of the production process. Summary of the invention

[0005] The purpose of the present invention is to provide a growth method of quasi-van der Waals epitaxial gallium nitride material, which can complete plasma treatment and epitaxial growth in situ, so as to solve the problems that the quality of general van der Waals epitaxial crystals is poor, the growth quantity is small and the growth rate is slow when MBE is used for quasi-van der Waals epitaxy, and the substrate treated with plasma in MOCVD for quasi-van der Waals epitaxy is contaminated during the transmission process.

[0006] To achieve the above object, the present invention provides a method for growing a quasi-van der Waals epitaxial gallium nitride film, which comprises the following steps:

[0007] Step 101, transferring or directly growing a two-dimensional material layer on a substrate;

[0008] Step 102, treating the two-dimensional material layer by plasma enhanced MOCVD method;

[0009] Step 103 , performing quasi-van der Waals epitaxial growth of gallium nitride on the processed two-dimensional material layer to form a gallium nitride single crystal thin film.

[0010] The present invention provides a method for growing a quasi-van der Waals epitaxial gallium nitride film, which utilizes a plasma-enhanced MOCVD method with a plasma component in a reaction chamber to perform plasma treatment on a two-dimensional material layer on a substrate, thereby forming unsaturated CN dangling bonds on the surface of the two-dimensional material. The dangling bonds serve as nucleation sites to promote the growth of gallium nitride, thereby overcoming the problem that in simple van der Waals epitaxy, only relatively low-intensity van der Waals forces exist on the surface of the two-dimensional material to interact with the gallium nitride grown thereon, which makes it difficult to obtain the nucleation and growth of gallium nitride single crystals.

[0011] According to a specific embodiment of the present invention, preferably, the substrate is a sapphire substrate, a silicon single crystal substrate, a spinel substrate, a silicon carbide substrate, a zinc oxide substrate, an aluminum nitride composite substrate grown on sapphire, a gallium nitride composite substrate grown on sapphire, a gallium nitride substrate or an aluminum nitride substrate.

[0012] According to a specific embodiment of the present invention, preferably, the substrate is a sapphire substrate, and the orientation of the sapphire substrate is (0001).

[0013] According to a specific embodiment of the present invention, preferably, the two-dimensional material is single-crystalline graphene or h-boron nitride.

[0014] According to a specific embodiment of the present invention, preferably, the two-dimensional material layer is 1-3 layers of graphene, or h-boron nitride with a thickness of 1-4 nm.

[0015] According to a specific embodiment of the present invention, preferably, the thickness of the single-layer graphene is 0.35 nm, and the thickness of the two-dimensional material layer is 0.35 nm-2 nm.

[0016] According to a specific embodiment of the present invention, preferably, the h-boron nitride is grown directly on the substrate by MOCVD method.

[0017] According to a specific embodiment of the present invention, preferably, the method of transferring the two-dimensional material layer is wet transfer.

[0018] According to a specific embodiment of the present invention, preferably, the wet transfer further comprises: using polymethyl methacrylate to solidify the two-dimensional material layer to form a support film; more preferably, the solidification temperature is 100-150°C.

[0019] According to a specific embodiment of the present invention, preferably, the wet transfer also includes: etching and removing the substrate on which the two-dimensional material is grown, transferring the two-dimensional material with the cured film from the solution into deionized water for cleaning after etching, transferring and attaching it to the target substrate, drying it, and baking it to remove moisture; then removing the polymethyl methacrylate to obtain a single layer of two-dimensional material, followed by annealing.

[0020] According to a specific embodiment of the present invention, preferably, the process of preparing a single-layer two-dimensional material is repeated to obtain a multi-layer two-dimensional material.

[0021] According to a specific embodiment of the present invention, preferably, the treatment method of step 102 is nitrogen plasma treatment, which specifically includes: heating the reaction chamber of the plasma enhanced MOCVD under a hydrogen atmosphere, then stopping the introduction of hydrogen, starting to introduce nitrogen, and using a radio frequency power supply to convert the nitrogen into nitrogen plasma, so as to treat the surface of the two-dimensional material layer to form dangling bonds.

[0022] According to a specific embodiment of the present invention, preferably, in step 103, the metal gallium source for growing gallium nitride is triethylgallium or trimethylgallium.

[0023] According to a specific embodiment of the present invention, preferably, in step 103, a plasma-assisted MOCVD device is used to carry out quasi-van der Waals epitaxial GaN epitaxial growth, preferably nitrogen is used as a carrier gas, the RF power is preferably 750-950W, the nitrogen flow rate is preferably 200-300sccm, the TEGa flow rate is preferably 60-100sccm, the gas pressure of the reaction chamber is preferably 2-5Pa, the temperature is preferably 700-800°C, and the thickness of the grown GaN is preferably 500nm-3μm.

[0024] According to a specific embodiment of the present invention, preferably, in step 103, the gallium nitride is grown by a two-step method: firstly, a nucleation layer is grown at a low temperature, and then a gallium nitride single crystal thin film is formed by high temperature growth.

[0025] The present invention also provides a gallium nitride film, which is prepared by the above growth method.

[0026] The method provided by the present invention uses plasma enhanced MOCVD to perform quasi van der Waals epitaxy, and can complete plasma treatment and epitaxial growth in situ. Compared with MBE equipment, this method has the characteristics of fast growth speed and large growth quantity in quasi van der Waals epitaxy; compared with traditional MOCVD, it can reduce the possibility of contamination of two-dimensional materials during substrate transfer and improve the quality of crystal growth.

[0027] The beneficial effects of the present invention are:

[0028] 1. The preparation method provided by the present invention adopts quasi-van der Waals epitaxy to introduce covalent bonds at the interface between the two-dimensional material and the epitaxial layer, and utilizes the unsaturated dangling bonds provided by the surface defects after the two-dimensional material is treated as nucleation sites to induce highly oriented gallium nitride nucleation, and expand and merge to form a single crystal gallium nitride film, thereby overcoming the problem of difficulty in obtaining high-quality single crystal nitridation in van der Waals epitaxy due to the presence of only low-strength van der Waals forces on the surface of the two-dimensional material.

[0029] 2. The preparation method provided by the present invention combines the advantages of MOCVD and MBE in quasi-van der Waals epitaxy, and can perform plasma treatment on the two-dimensional material on the substrate to form dangling bonds, and directly grow subsequent gallium nitride thereon without transferring to other equipment, thereby reducing or even avoiding the pollution and damage to the two-dimensional material caused by the transfer of the substrate. At the same time, compared with the quasi-van der Waals epitaxial growth of MBE equipment, it has the ability to grow on multiple substrates at one time, and has good industrial application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic flow chart of the quasi-van der Waals epitaxial gallium nitride thin film epitaxy method of the present invention;

[0031] Figure 2 A schematic diagram of the structure of an epitaxial wafer obtained by the method of the present invention;

[0032] Figure 3 The XRD rocking curve of the (002) surface of the GaN epitaxial layer prepared in Example;

[0033] Figure 4 The XRD rocking curve of the GaN epitaxial layer (102) prepared in the embodiment;

[0034] Figure 5 The SEM scanning image of the surface morphology of the GaN film prepared in the example:

[0035] Figure 6 This is an optical microscope photograph of the interface region of the GaN film prepared in Example after peeling.

[0036] Description of Figure Numbers:

[0037] 1-substrate, 2-two-dimensional material layer, 3-GaN material film. DETAILED DESCRIPTION

[0038] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it should not be construed as limiting the applicable scope of the present invention.

[0039] The present invention provides a method for growing a quasi-van der Waals epitaxial gallium nitride film, the process of which is as follows: Figure 1 As shown, the structure of the prepared epitaxial wafer is as follows Figure 2 The preparation method comprises the following specific steps:

[0040] Step 101, transfer or directly grow a two-dimensional material layer 2 on a prepared substrate 1; the two-dimensional material layer is the basis of quasi-van der Waals epitaxy, and the force between the two-dimensional material layer and the substrate is van der Waals force rather than covalent bond, which weakens the influence of the substrate on the epitaxial layer above, thereby broadening the substrate selection range for epitaxial gallium nitride.

[0041] In step 101, the substrate material may be a sapphire substrate, a silicon single crystal substrate, a spinel substrate, a silicon carbide substrate, a zinc oxide substrate, an aluminum nitride composite substrate grown on sapphire, a gallium nitride composite substrate grown on sapphire, a gallium nitride substrate or an aluminum nitride substrate; the substrate size may be 2 inches or 4 inches.

[0042] In step 101, before forming the two-dimensional material layer 2, the substrate 1 can be cleaned by ultrasonic cleaning, and residual moisture must be removed after cleaning; the cleaning agents used in the ultrasonic cleaning can be ultrapure water, acetone, isopropanol and deionized water in order, and the time can be 5-15 minutes for each cleaning step; the method for removing residual moisture can be blowing dry with a nitrogen gun or oven drying, the drying temperature can be 150-250°C, and the drying time can be 15-120 minutes.

[0043] The two-dimensional material in step 101 can be single crystal graphene, and the growth method of graphene can be to grow it on the surface of copper foil using CVD technology; the substrate for graphene growth can be a copper (111) substrate; the growth pressure can be atmospheric pressure; the growth temperature can be 950-1100°C; 400-600sccm of Ar and 10-200sccm of H2 can be introduced as carrier gas; the carbon source for graphene growth can be methane; the methane flow rate during graphene growth can be 5-30sccm; and the graphene growth time can be 1-3 hours.

[0044] The two-dimensional material in step 101 may be h-boron nitride (h-BN), and the h-BN may be grown directly on a substrate by MOCVD.

[0045] In step 101 , the number of layers of the two-dimensional material may be 1-3 layers of graphene; the thickness of h-BN may be 1-4 nm.

[0046] The method of transferring the two-dimensional material layer in step 101 can be a wet transfer method; wherein the solution used in the wet transfer does not react with the substrate. The wet transfer can use polymethyl methacrylate to solidify the two-dimensional material layer to form a support film, wherein the curing temperature can be 100-150°C; after curing, the substrate on which the two-dimensional material grows is etched, and specifically (NH)4S2O8 aqueous solution can be selected, and the concentration of the aqueous solution can be 0.5-2mol / L; after etching, the two-dimensional material with the solidified film is separated and can be washed with deionized water; then the two-dimensional material with the solidified film is attached to the target substrate, and can be dried at a temperature of 150-200°C for 2-4 hours to remove moisture; then the solidified film can be removed with hot acetone, and a layer of two-dimensional material is obtained after the removal is completed; repeat this process to obtain more layers of two-dimensional material. After obtaining a suitable number of layers, annealing can be used to remove organic matter and oxide residues, wherein the annealing temperature can be 300-400° C.; the annealing can be performed in an atmosphere of 50-200 sccm hydrogen and 200-400 sccm argon; and the annealing time can be 2-4 hours.

[0047] Step 102, treating the two-dimensional material layer 2 obtained in step 101 in a plasma enhanced MOCVD device to improve the surface conditions of the two-dimensional material and create defects on the surface of the two-dimensional material. These defects will provide unsaturated dangling bonds, which can serve as nucleation sites for gallium nitride, triggering highly oriented nucleation and forming a single crystal film.

[0048] The treatment method in step 102 can be nitrogen plasma treatment, and the reaction chamber of the plasma enhanced MOCVD is heated in a hydrogen atmosphere, wherein the flow rate of hydrogen can be 50-200sccm, the temperature can be 700-800°C, and the heating time can be 5-15min; then the introduction of hydrogen is stopped, and nitrogen is started, and the nitrogen is converted into nitrogen plasma by using a radio frequency power supply to treat the surface of the two-dimensional material layer to form dangling bonds, wherein the power of the radio frequency can be 750-950W, the flow rate of nitrogen can be 100-200sccm, the gas pressure of the reaction chamber can be 1-5pa, and the treatment time can be 1-3min.

[0049] Step 103 , introducing a metal gallium source and a nitrogen source, and performing quasi-van der Waals epitaxial growth of gallium nitride on the two-dimensional material layer 2 processed in step 102 to form a gallium nitride single crystal thin film 3 .

[0050] In step 103 , the metal gallium source may be triethylgallium (TEGa) or trimethylgallium (TMGa).

[0051] In step 103 , the nitrogen source may be nitrogen plasma or ammonia gas.

[0052] In step 103, nitrogen or hydrogen may be used as a carrier gas when growing the GaN material film.

[0053] In step 103, a plasma-assisted MOCVD device can be used to perform quasi-van der Waals epitaxial GaN epitaxial growth, wherein nitrogen can be selected as a carrier gas, the RF power can be 750-950W, the nitrogen flow rate can be 200-300sccm, the TEGa flow rate can be 60-100sccm, the gas pressure of the reaction chamber can be 2-5Pa, the temperature can be 700-800°C, and the thickness of the grown GaN can be 500nm-3μm.

[0054] In step 103, MOCVD equipment can be used to perform quasi-van der Waals GaN epitaxial growth, and a two-step method can be used for growth, wherein: the low-temperature nucleation layer can be grown for 5-10 minutes under the conditions of NH3 flow rate 5000-10000sccm, TMGa 5-10sccm, and temperature 570-620°C, and the reaction chamber pressure can be 100-400mbar; the high-temperature growth can be grown under the conditions of NH3 flow rate 3000-8000sccm, TMGa 30-50sccm, and temperature 1000-1100°C, and the reaction chamber pressure can be 100-400mbar, and the thickness of the high-temperature grown GaN can be 500nm-4μm, preferably 1μm-3μm.

[0055] Example

[0056] This embodiment provides a method for growing a quasi-van der Waals epitaxial gallium nitride film, comprising the following steps:

[0057] A 2-inch single-crystal single-polished sapphire (0001) substrate was selected as the epitaxial substrate and ultrasonically cleaned in ultrapure water, acetone, isopropanol, and deionized water in turn as preparation for wet transfer. After the cleaning work was completed, the residual moisture on the surface was blown dry with N2 to prevent moisture from contaminating the subsequent two-dimensional materials.

[0058] The three-layer single-crystalline graphene two-dimensional material was transferred to a sapphire substrate by wet transfer, wherein the synthesis of graphene was as follows: a copper (111) substrate was placed in a CVD device, 500 sccm Ar and 15 sccm H2 were introduced at atmospheric pressure and heated to 1020°C, and then 15 sccm CH4 was introduced for graphene growth, and the growth time was 2.5 hours; after the growth was completed, the CH4 gas flow was turned off and the sample was cooled to room temperature; the wet transfer process was as follows: first, a layer of polymethyl methacrylate (PMMA) was spin-coated on the surface of graphene / Cu, and then cured at 135°C to form a support film; then, the PMMA / graphene film was separated from the growth substrate by etching the Cu film under the graphene in a (NH)4S2O8 (1.5 mol / L) aqueous solution. After coming out, washing with deionized water, attaching the PMMA / graphene film to the target substrate, drying at room temperature and baking at 185°C for 4 hours to remove moisture; then removing the PMMA layer with hot acetone to obtain a transferred layer of graphene on the target substrate; repeating the above steps to obtain more layers of graphene; after the transfer, annealing for 4 hours at 400°C in a 120sccm hydrogen and 350sccm argon environment to remove organic matter and oxide residues; wherein the solution used in the wet transfer does not react with the amorphous substrate.

[0059] The substrate with the transferred graphene is placed on the graphite disk in the reaction chamber of the plasma enhanced MOCVD equipment, and the graphene surface is treated, specifically including: first, 70 sccm of hydrogen is introduced, the air pressure in the reaction chamber is reduced to 1 Pa by a molecular pump, the rotation speed of the graphite disk is set to 250 revolutions per minute, and the temperature is started to rise, and the temperature is raised from room temperature to 700°C within 15 minutes to complete the heating process; then the introduction of hydrogen is stopped and replaced with nitrogen, and the nitrogen is converted into nitrogen plasma by an RF power supply, the forward RF power is 950 W, the flow rate of nitrogen is 140 sccm, the air pressure in the reaction chamber is controlled to be 1 Pa, the treatment time is 3 minutes, and the temperature is maintained at 700°C during the treatment to complete the treatment of the graphene surface.

[0060] Quasi-van der Waals epitaxial growth of GaN is carried out on the processed graphene / sapphire substrate, specifically including: maintaining the forward RF power at 950W, the nitrogen flow rate at 140sccm, the gas pressure in the reaction chamber at 1pa, the temperature at 700°C, and gradually starting to introduce TEGa within one minute, with the flow rate increasing from 0 to 78sccm; then reducing the RF power to 850W, increasing the nitrogen flow rate from 140sccm to 240sccm, and introducing 30sccm of hydrogen to carry out GaN quasi-van der Waals epitaxial growth for 2 hours to obtain a GaN film about 500nm thick.

[0061] The XRD rocking curves of the (002) and (102) planes of the GaN epitaxial layer prepared in this embodiment are shown in Figures 1 and 2. Figure 3 and Figure 4 As shown, the SEM scanning image of the GaN film surface is as follows Figure 5 As shown. Figure 3-Figure 5 It can be seen that the GaN film has a high crystal quality.

[0062] Figure 6 This is an optical microscope photograph of the interface region of the GaN film prepared in Example after peeling. Figure 6 The brighter area in the middle is the exposed substrate after GaN stripping. Figure 6 It can be seen that the GaN film has good strippability.

Claims

1. A method for growing a quasi-van der Waals epitaxial gallium nitride film, comprising the following steps: Step 101, transferring or directly growing a two-dimensional material layer on a substrate; Step 102, treating the two-dimensional material layer by plasma enhanced MOCVD method; Step 103 , performing quasi-van der Waals epitaxial growth of gallium nitride on the processed two-dimensional material layer to form a gallium nitride single crystal thin film.

2. The growth method according to claim 1, wherein: The substrate is a sapphire substrate, a silicon single crystal substrate, a spinel substrate, a silicon carbide substrate, a zinc oxide substrate, an aluminum nitride composite substrate grown on sapphire, a gallium nitride composite substrate grown on sapphire, a gallium nitride substrate or an aluminum nitride substrate; Preferably, the size of the substrate is 2 inches to 4 inches; Preferably, the substrate is a sapphire substrate, and the orientation of the sapphire substrate is (0001).

3. The growth method according to claim 1, wherein: The two-dimensional material is single crystal graphene or h-boron nitride; Preferably, the two-dimensional material layer is 1-3 layers of graphene, or h-boron nitride with a thickness of 1-4 nm; Preferably, the thickness of the single-layer graphene is 0.35 nm, and the thickness of the two-dimensional material layer is 0.35 nm-2 nm.

4. The growth method according to claim 3, wherein: The graphene is synthesized by CVD method; Preferably, the substrate on which the graphene is grown is a copper (111) substrate; Preferably, the pressure of graphene growth is atmospheric pressure; Preferably, the temperature of the growth of the graphene is 950-1100°C; Preferably, the carbon source for the growth of the graphene is methane; more preferably, the methane flow rate during the growth of the graphene is 5-30 sccm; Preferably, during the growth process of the graphene, 400-600 sccm of Ar and 10-200 sccm of H2 are introduced as carrier gases; Preferably, the growth time of the graphene is 1-3 hours.

5. The growth method according to claim 3, wherein: The h-boron nitride is grown directly on the substrate by MOCVD method.

6. The growth method according to claim 1, wherein: The method of transferring the two-dimensional material layer is wet transfer; Preferably, the solution used in the wet transfer does not react with the substrate; Preferably, the wet transfer further comprises: curing the two-dimensional material layer using polymethyl methacrylate to form a support film; more preferably, the curing temperature is 100-150° C.; Preferably, the wet transfer further comprises: etching and removing the substrate on which the two-dimensional material is grown, transferring the two-dimensional material with the solidified film from the solution into deionized water for cleaning after etching, transferring and attaching it to the target substrate, air-drying it, and baking it to remove moisture; then removing the polymethyl methacrylate to obtain a single-layer two-dimensional material, and then performing annealing treatment; More preferably, the etching is performed using an aqueous solution of ammonium persulfate (with a concentration of 0.5-2 mol / L); More preferably, the drying is performed at 150-200° C. for 2-4 hours; More preferably, the removal of polymethyl methacrylate is carried out in acetone; Preferably, the process of preparing a single layer of two-dimensional material is repeated to obtain a multi-layer two-dimensional material; Preferably, the annealing temperature is 300-400° C., the annealing atmosphere is preferably 50-200 sccm hydrogen and 200-400 sccm argon, and the annealing time is preferably 2-4 hours.

7. The growth method according to claim 1, wherein: The treatment method of step 102 is nitrogen plasma treatment, which specifically includes: heating the plasma enhanced MOCVD reaction chamber in a hydrogen atmosphere, then stopping the introduction of hydrogen, starting to introduce nitrogen, and using a radio frequency power supply to convert the nitrogen into nitrogen plasma, so as to treat the surface of the two-dimensional material layer to form dangling bonds; During the heating process, the flow rate of hydrogen is preferably 50-200 sccm, the heating temperature is preferably 700-800°C, and the heating time is preferably 5-15 min; Preferably, the power of the radio frequency is 750-950W; Preferably, the flow rate of the nitrogen gas is 100-200 sccm; Preferably, the gas pressure of the reaction chamber is 1-5 Pa; Preferably, the treatment time is 1-3 min.

8. The growth method according to claim 1, wherein: In step 103, the metal gallium source for growing gallium nitride is triethylgallium or trimethylgallium; In step 103, the nitrogen source when growing gallium nitride is nitrogen plasma or ammonia; In step 103, nitrogen or hydrogen is used as a carrier gas when growing gallium nitride; In step 103, a plasma-assisted MOCVD device is used to perform quasi-van der Waals GaN epitaxial growth. Nitrogen is preferably used as a carrier gas, the RF power is preferably 750-950 W, the nitrogen flow rate is preferably 200-300 sccm, the TEGa flow rate is preferably 60-100 sccm, the gas pressure of the reaction chamber is preferably 2-5 Pa, the temperature is preferably 700-800°C, and the thickness of the grown GaN is preferably 500 nm-3 μm.

9. The growth method according to claim 8, wherein: In step 103, the gallium nitride is grown by a two-step method: firstly, a nucleation layer is grown at a low temperature, and then a gallium nitride single crystal thin film is formed by high temperature growth; Preferably, the preparation process of the nucleation layer is to grow for 5-10 minutes under the conditions of NH3 flow rate 5000-10000sccm, TMGa flow rate 5-10sccm, temperature 570-620°C, and the reaction chamber pressure during the process is 100-400mbar; Preferably, the high temperature growth process is carried out under the conditions of NH3 flow rate of 3000-8000sccm, TMGa flow rate of 30-50sccm, and temperature of 1000-1100°C, and the reaction chamber pressure during the process is preferably 100-400mbar; Preferably, the thickness of the GaN material film grown at high temperature is 500 nm-4 μm, more preferably 1 μm-3 μm.

10. A gallium nitride thin film prepared by the growth method according to any one of claims 1 to 9.

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