A transfer method of a two-dimensional bismuth oxy selenide film and a hetero integration method thereof

Abstract

The application provides a two-dimensional bismuth selenide oxide film transfer method and a hetero-integration method thereof, and relates to the technical field of semiconductor materials.The two-dimensional bismuth selenide oxide film transfer method provided by the application realizes lossless and clean transfer of the bismuth selenide oxide film through a composite transfer medium of a TRT layer / a support layer / a stress layer / an oxide layer.In the transfer process, the oxide layer serves as a contact layer to ensure that the bismuth selenide oxide is not damaged in the transfer process, and excellent electrical properties of the bismuth selenide oxide are ensured.The stress layer provides tensile stress, and can realize dry lossless peeling of wafer-level bismuth selenide oxide.The support layer can avoid cracking of the film in the peeling process, realize lossless and clean transfer of the bismuth selenide oxide film, and the bismuth selenide oxide film after transfer is complete and continuous, the surface is flat, the surface roughness is less than 0.65 nm, and the film uniformity is good.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor materials, and in particular to a two-dimensional bismuth selenide oxide film transfer method and a hetero-integration method thereof. BACKGROUND

[0002] Two-dimensional bismuth selenide oxide is a new type of air-stable high-mobility two-dimensional semiconductor material, which is a tetragonal phase, and is formed by alternately stacking positively charged [Bi2O2] n 2n+ and negatively charged [Se] n 2n- The unique crystal structure and band structure of two-dimensional bismuth selenide oxide make it have very excellent properties, such as super-high carrier mobility, suitable band gap, and small effective mass. Notably, two-dimensional bismuth selenide oxide has a native high-quality gate oxide of bismuth selenide, and the interface is atomically flat, which can be comparable to SiO2 / Si. Therefore, two-dimensional bismuth selenide oxide has attracted widespread attention from the industry and academia, and has shown its potential practical value in the fields of electronic devices, optoelectronic devices, flexible devices, and memory devices. K

[0003] At present, high-quality bismuth selenide oxide nanosheets and films can be obtained on mica, strontium titanate, lanthanum aluminate, and other substrates by chemical vapor deposition (CVD), molecular beam epitaxy (MBE), pulsed laser deposition (PLD), and metal organic chemical vapor deposition (MOCVD) methods. Notably, to realize the hetero-integration of bismuth selenide oxide and silicon-based substrates and construct multifunctional optoelectronic devices, a reliable wafer-level bismuth selenide oxide film transfer method is needed to transfer it from the growth substrate surface without damage and clean, so as to be hetero-integrated with the target functional substrate. However, the existing transfer method uses polymethyl methacrylate (PMMA) as a transfer medium and uses hydrofluoric acid (HF) wet etching of the substrate, which will damage the crystal quality of bismuth selenide oxide and seriously affect its properties, and these methods can only transfer micron-sized nanosheets, with low transfer efficiency. Therefore, developing a non-destructive, clean, wafer-level bismuth selenide oxide film transfer method will help the development of bismuth selenide oxide in the fields of electronics and optoelectronics.

[0004] The prior art CN116053338A discloses a MoO 3-x ​A preparation method of a near-infrared photoelectric sensor of Bi2O2Se hetero-integration discloses a method for transferring layered Bi2O2Se nanosheets to a SiO2 / Si wafer from a mica substrate, using PMMA as a transfer medium, and then removing the substrate by etching with hydrofluoric acid to realize the transfer of Bi2O2Se nanosheets. It can be seen that the transfer method of the two-dimensional bismuth selenide oxide film in the prior art does not solve the problem of damage to the crystal quality of bismuth selenide oxide, and cannot improve the transfer efficiency of the two-dimensional bismuth selenide oxide film. SUMMARY

[0005] The present application is directed to the defects and deficiencies of the current wafer-level bismuth selenide oxide film transfer method, which causes damage to the crystal quality of bismuth selenide oxide, seriously affects its properties, and has low transfer efficiency. A two-dimensional bismuth selenide oxide film transfer method is provided, which realizes non-destructive and clean transfer of wafer-level bismuth selenide oxide film through a specific transfer medium, and improves the transfer efficiency of two-dimensional bismuth selenide oxide film.

[0006] Another object of the present application is to provide a two-dimensional bismuth selenide oxide film hetero-integration method.

[0007] In a first aspect, the present application provides a two-dimensional bismuth selenide oxide film transfer method, comprising the following steps:

[0008] S1. Forming an oxide layer, a stress layer, a support layer and a TRT layer on the surface of the two-dimensional bismuth selenide oxide film in sequence to obtain a composite structure of TRT layer / support layer / stress layer / oxide layer / two-dimensional bismuth selenide oxide / growth substrate;

[0009] S2. Peeling the TRT / support layer / stress layer / oxide layer / two-dimensional bismuth selenide oxide from the surface of the growth substrate, and then transferring the two-dimensional bismuth selenide oxide to a target substrate.

[0010] According to the two-dimensional bismuth selenide oxide film transfer method provided by the present application, preferably, the composite structure at least meets one of the following conditions:

[0011] (1) The thickness of the oxide layer is 2-20 nm;

[0012] (2) The thickness of the stress layer is 300-2000 nm;

[0013] (3) The thickness of the support layer is 1000-3000 nm.

[0014] According to the two-dimensional bismuth selenide oxide film transfer method provided by the present application, preferably, the oxide of the oxide layer in S1 includes hafnium oxide and / or aluminum oxide, and / or, the stress layer in S1 is any one of a Cr layer, a Mo layer, a Pt layer and a Ni layer, and the support layer is an Au layer, an Ag layer or a Cu layer.

[0015] According to the method for transferring the two-dimensional bismuth selenide oxide film provided by the application, preferably, the oxide layer in S1 is formed in any one of the following manners:

[0016] (1) atomic layer deposition, the deposition source of the atomic layer deposition is hafnium tetra (dimethylamino), trimethylaluminum and water, and the growth temperature is 100-250 DEG C;

[0017] (2) electron beam evaporation, and the deposition rate is 0.1-5 angstrom / s.

[0018] According to the method for transferring the two-dimensional bismuth selenide oxide film provided by the application, preferably, the specific operation of transferring the two-dimensional bismuth selenide oxide to the target substrate in S2 is as follows:

[0019] After the two-dimensional bismuth selenide oxide is peeled off from the surface of the growth substrate, a PPC layer and a PDMS layer are sequentially formed on the surface of the two-dimensional bismuth selenide oxide, a TRT layer / support layer / stress layer / oxide layer / two-dimensional bismuth selenide oxide / PPC / PDMS structure is obtained, the TRT layer and the support layer / stress layer are removed, the two-dimensional bismuth selenide oxide is attached to the target substrate through the PDMS layer, and then the PDMS layer and the PPC layer are removed, so that the two-dimensional bismuth selenide oxide is transferred to the target substrate.

[0020] According to the method for transferring the two-dimensional bismuth selenide oxide film provided by the application, preferably, the support layer / stress layer is removed by etching with a ferric chloride solution.

[0021] According to the method for transferring the two-dimensional bismuth selenide oxide film provided by the application, preferably, the etching concentration of the ferric chloride solution etching is 0.5-2 mol / L, and the etching time is 1-5 min.

[0022] According to the method for transferring the two-dimensional bismuth selenide oxide film provided by the application, preferably, the PPC layer on the surface of the two-dimensional bismuth selenide oxide is formed in the following manner:

[0023] The PPC solution is spin-coated on the surface of the two-dimensional bismuth selenide oxide to form a PPC layer, the spin-coating rotation speed is 1000-10000 rpm, and the baking and gelation temperature is 50-120 DEG C.

[0024] In the second aspect, the application further provides a method for hetero-integrating two-dimensional bismuth selenide oxide, which transfers the two-dimensional bismuth selenide oxide to a target substrate by using the method for transferring the two-dimensional bismuth selenide oxide film provided by the application, so as to realize the hetero-integration of the two-dimensional bismuth selenide oxide.

[0025] According to the method for hetero-integrating two-dimensional bismuth selenide oxide provided by the application, preferably, the target substrate comprises any one of a silicon wafer, a silicon oxide wafer, quartz and a polyethylene terephthalate substrate.

[0026] Beneficial effects:

[0027] The transfer method of the two-dimensional bismuth selenide oxide film provided by the application realizes lossless and clean transfer of the bismuth selenide oxide film through the composite transfer medium of the TRT layer / support layer / stress layer / oxide layer. In the transfer process, the oxide layer as the contact layer can ensure that the bismuth selenide oxide is not damaged in the transfer process, and ensure excellent electrical properties thereof. The stress layer provides tensile stress, and can realize dry lossless peeling of the wafer-level bismuth selenide oxide. The support layer can avoid cracking of the film in the peeling process, and realize lossless and clean transfer of the bismuth selenide oxide film.

[0028] The bismuth selenide oxide film transferred by the transfer method of the application is complete and continuous, has a smooth surface, a surface roughness less than 0.65 nm, and good film uniformity. The growth substrate after dry peeling can be used for repeated growth of the bismuth selenide oxide film, and the growth substrate can be repeatedly peeled and reused. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to make the content of the application more easily understood, the application will be further described in detail below according to specific embodiments of the application and in conjunction with the drawings.

[0030] Figure 1 It is a flowchart of the two-dimensional bismuth selenide wafer transfer method of the application.

[0031] Figure 2 It is a morphology diagram and an optical microscope diagram of the two-dimensional bismuth selenide after peeling and after transfer in Example 1, wherein a is the morphology diagram of the two-dimensional bismuth selenide after peeling, b is the morphology diagram of the two-dimensional bismuth selenide after transfer, and c is the optical microscope diagram of the two-dimensional bismuth selenide wafer after transfer.

[0032] Figure 3 It is a surface roughness statistic of the bismuth selenide oxide film after transfer in Example 1, and the embedded diagram is an atomic force microscope image of the surface of the two-dimensional bismuth selenide oxide film after transfer.

[0033] Figure 4 It is a Raman spectrum diagram of the bismuth selenide oxide film after transfer in Example 1.

[0034] Figure 5 It is a typical field effect transistor performance curve of the bismuth selenide oxide film after transfer in Example 1.

[0035] Figure 6 It is an optical image of repeated growth and peeling in Example 2.

[0036] Figure 7 It is a morphology diagram and an optical microscope diagram of the two-dimensional bismuth selenide film after peeling and after transfer in Example 3, wherein a is the morphology diagram of the two-dimensional bismuth selenide after peeling, b is the morphology diagram of the two-dimensional bismuth selenide after transfer, and c is the optical microscope diagram of the two-dimensional bismuth selenide wafer after transfer.

[0037] Figure 8 The morphology and optical microscope images of the two-dimensional bismuth selenide oxide film after peeling and transferring are shown in Figure 1, wherein a is the morphology of the two-dimensional bismuth selenide oxide film after peeling, b is the morphology of the two-dimensional bismuth selenide oxide film after transferring, and c is the optical microscope image of the two-dimensional bismuth selenide oxide wafer after transferring.

[0038] Figure 9 The morphology and optical microscope images of the two-dimensional bismuth selenide oxide film after peeling and transferring are shown in Figure 2, wherein a is the morphology of the two-dimensional bismuth selenide oxide film after peeling, b is the morphology of the two-dimensional bismuth selenide oxide film after transferring, and c is the optical microscope image of the two-dimensional bismuth selenide oxide wafer after transferring. DETAILED DESCRIPTION

[0039] The following examples are used to illustrate the present application, but are not used to limit the scope of the present application. If the specific technology or condition is not specified in the examples, the technology or condition described in the literature in the art or according to the product manual is used. If the manufacturer of the reagent or instrument is not specified, it is a conventional product that can be purchased through a regular channel.

[0040] Abbreviations:

[0041] TRT: thermal release tape;

[0042] PPC: polypropylene carbonate;

[0043] PDMS: polydimethylsiloxane film.

[0044] In the specific embodiment, the present application provides a transfer method of a two-dimensional bismuth selenide oxide film, comprising the following steps:

[0045] S1. Forming an oxide layer, a stress layer, a support layer and a TRT layer on the surface of the two-dimensional bismuth selenide oxide film in sequence to obtain a composite structure of TRT layer / support layer / stress layer / oxide layer / two-dimensional bismuth selenide oxide / growth substrate;

[0046] S2. Peeling the TRT / support layer / stress layer / oxide layer / two-dimensional bismuth selenide oxide from the surface of the growth substrate, and then transferring the two-dimensional bismuth selenide oxide to a target substrate.

[0047] It should be noted that:

[0048] In the two-dimensional bismuth selenide oxide thin film transfer method provided by the present invention, a composite transfer medium consisting of a TRT layer, a support layer, a stress layer, and an oxide layer is formed on the surface of the two-dimensional bismuth selenide oxide thin film. The oxide layer in the composite transfer medium acts as a contact layer to ensure that the bismuth selenide oxide is not damaged during the transfer process and to guarantee its excellent electrical properties. The stress layer provides tensile stress, enabling dry non-destructive peeling of wafer-level bismuth selenide oxide. The support layer increases the toughness of the stress layer and prevents cracks from forming in the support layer / stress layer during the peeling process. The TRT layer acts as a self-supporting layer to facilitate the transfer operation. Through the action of the TRT layer, the support layer / stress layer / oxide layer / two-dimensional bismuth selenide oxide as a whole can be peeled off from the growth substrate surface without damage and cleanly. Then, combined with the bonding medium, it is transferred to a new target substrate.

[0049] The two-dimensional bismuth selenide oxide film mentioned in this invention is preferably a wafer-level two-dimensional bismuth selenide oxide film, which can achieve non-destructive and clean transfer of large-size wafer-level two-dimensional bismuth selenide oxide films of two inches or more.

[0050] In specific embodiments, the oxide layer mentioned in this invention is an oxide resistant to corrosion by oxidizing acidic solutions such as ferric chloride. To better protect the oxide layer's resistance to corrosion by oxidizing acidic solutions such as ferric chloride and prevent ferric chloride from penetrating the oxide layer and damaging bismuth selenide oxide, the thickness of the oxide layer in the composite structure mentioned in this invention is preferably 2~20 nm, more preferably 3~10 nm, for example, it can be a value of 2 nm, 4 nm, 5 nm, 6 nm, 8 nm, 10 nm, 12 nm, 14 nm, 16 nm, 18 nm or 20 nm or any range thereof. Meanwhile, if the oxide layer thickness is too thick, it will increase the rigidity of the oxide / bismuth selenide oxide, which is not conducive to conformal bonding to the target substrate and is prone to breakage. Therefore, the thickness is preferably no more than 20 nm.

[0051] In a specific embodiment, the growth temperature of the oxide layer is preferably 100~250℃, more preferably 100~150℃.

[0052] In order to provide sufficient strain energy to peel off the bismuth selenide oxide film without increasing the time for depositing the metal film, the thickness of the stress layer in the composite structure mentioned in this invention is preferably 300~2000nm, more preferably 500~1000nm, for example, it can be a point value of 300nm, 500nm, 800nm, 1000nm, 1200nm, 1500nm, 1800nm ​​or 2000nm or any range thereof.

[0053] Similarly, in order to avoid the cracking of the bismuth selenide film during the peeling, while not increasing the plating time, the thickness of the support layer in the composite structure mentioned in the present application is preferably 1000-3000 nm, more preferably 1500-2000 nm, for example, it can be 1000 nm, 1200 nm, 1500 nm, 1800 nm, 2000 nm, 2200 nm, 2500 nm, 2800 nm or 3000 nm, etc. Point value or range value composed of any of them.

[0054] The thickness of the oxide layer, the thickness of the stress layer and the thickness of the support layer in the composite structure mentioned in the present application can be individually preferred, or can be jointly preferred, and the more preferred embodiment is to simultaneously and synergistically optimize the thickness of the oxide layer, the thickness of the stress layer and the thickness of the support layer.

[0055] In a specific embodiment, the oxide layer of the present application serves as a contact layer, which can ensure that the bismuth selenide is not damaged during the transfer process and ensures its excellent electrical properties. Any oxide that can achieve this function in the art can be used as the material of the oxide layer of the present application, for example, it can be preferably hafnium oxide and / or aluminum oxide.

[0056] In a specific embodiment, the stress layer submitted in the present application provides tensile stress, which can achieve dry and non-destructive peeling of wafer-level bismuth selenide. The support layer submitted in the present application can avoid cracking of the film during the peeling process. Similarly, any material that can achieve the corresponding function in the art can be applied to prepare the stress layer and the support layer of the present application. For example, the stress layer in S1 is any one of Cr layer, Mo layer, Pt layer and Ni layer, and the support layer is Au layer, Ag layer or Cu layer.

[0057] In a specific embodiment, for example, the stress layer can be more preferably a nickel layer, and the support layer can be a copper layer.

[0058] Among them, the materials of the stress layer and the support layer mentioned in the present application can be individually preferred, or can be jointly preferred, and the more preferred embodiment is to simultaneously and synergistically optimize.

[0059] For example, in a specific embodiment, the stress layer is preferably a nickel layer with a thickness of 500 nm, and the support layer is a copper layer with a thickness of 1500 nm. The stress layer and the support layer can be formed by magnetron sputtering deposition.

[0060] In a specific embodiment, the formation method of the oxide layer in S1 of the present application is not specifically limited, and any method that can be achieved in the art can be used to form the oxide layer. For example, the following any one of the formation methods can be specifically used:

[0061] (1) Atomic layer deposition, the deposition source material of the atomic layer deposition is tetrakis (dimethylamino) hafnium, trimethylaluminum and water, and the growth temperature is 100-250 DEG C;

[0062] (2) Electron beam evaporation, the deposition rate is 0.1-5 angstrom / s.

[0063] In the specific embodiment, the oxide is preferably hafnium oxide, the forming method is atomic layer deposition, and the thickness is 5 nm.

[0064] In the specific embodiment, the application further provides a specific operation method for transferring the two-dimensional bismuth selenium oxide to the target substrate in S2.

[0065] After the two-dimensional bismuth selenium oxide is peeled off from the surface of the growth substrate, a PPC layer and a PDMS layer are formed on the surface of the two-dimensional bismuth selenium oxide in sequence, a TRT layer / support layer / stress layer / oxide layer / two-dimensional bismuth selenium oxide / PPC / PDMS structure is obtained, the TRT layer and the support layer / stress layer are removed, and the two-dimensional bismuth selenium oxide is attached to the target substrate through the PDMS layer, and then the PDMS layer and the PPC layer are removed.

[0066] In some specific embodiments, transferring the two-dimensional bismuth selenium oxide to the target substrate more preferably comprises the following steps:

[0067] S1. Covering a layer of oxide on the surface of the two-dimensional bismuth selenium oxide, then depositing a stress layer and a support layer, and attaching a thermal release tape (TRT) to obtain a composite structure one of “TRT / stress layer / support layer / oxide / two-dimensional bismuth selenium oxide / growth substrate”;

[0068] S2. Dry peeling the TRT / stress layer / support layer / oxide / two-dimensional bismuth selenium oxide from the surface of the growth substrate, then spin coating a layer of polypropylene carbonate (PPC) on the surface of the two-dimensional bismuth selenium oxide to obtain a composite structure two of “TRT / metal / oxide / two-dimensional bismuth selenium oxide / PPC”;

[0069] Attaching a polydimethylsiloxane film (PDMS) to the surface of the PPC in the composite structure two, heating to release the TRT, then etching the metal using a ferric chloride solution, removing the stress layer / support layer, cleaning and drying to obtain a composite structure three of “PDMS / PPC / two-dimensional bismuth selenium oxide / oxide”;

[0070] Attaching the composite structure three to the target substrate, heating to release the PDMS, and then using an organic solvent to remove the PPC after baking.

[0071] In the specific embodiment, the two-dimensional bismuth selenide oxide film mentioned in S1 of the present application is preferably a two-dimensional bismuth selenide oxide film with a thickness of 3-15 nm grown by chemical vapor deposition on a substrate such as "sapphire" and "strontium titanate", and the film size is preferably 2 inches or more. More preferably, the thickness of the bismuth selenide oxide film is 10 nm, and the growth substrate is sapphire.

[0072] In the specific embodiment, the dry peeling mentioned in S2 of the present application is preferably dry mechanical peeling, and TRT is used as a self-supporting layer to apply external stress to completely separate the two-dimensional bismuth selenide oxide film from the growth substrate.

[0073] The present application does not specifically limit the removal method of the specific TRT layer and the support layer / stress layer, and any removal method that ensures the clean and undamaged removal of the two-dimensional bismuth selenide oxide film is acceptable. In some specific embodiments, the support layer / stress layer mentioned in the present application can be removed by etching with a ferric chloride solution.

[0074] In other specific embodiments, in order to more thoroughly etch the metal of the support layer / stress layer without damaging the two-dimensional bismuth selenide oxide film, the present application further preferably uses a ferric chloride solution with an etching concentration of 0.5-2 mol / L to etch the support layer / stress layer, and the etching time is preferably 1-5 min. For example, the etching concentration can be 0.5 mol / L, 0.8 mol / L, 1.0 mol / L, 1.5 mol / L, 1.8 mol / L, 2 mol / L, etc. or any range value formed by any of them, and the etching time can be 1 min, 2 min, 3 min, 4 min, 5 min, etc. or any range value formed by any of them.

[0075] In some specific embodiments, the etching concentration of the ferric chloride solution is 1 mol / L, and the etching time is 5 min.

[0076] In some specific embodiments, after the stress layer / support layer is removed by etching with a ferric chloride solution, the number of cleaning times after cleaning and drying is preferably 3-5 times, and each cleaning time is 15 min.

[0077] In some specific embodiments, the formation method of the PPC layer on the surface of the two-dimensional bismuth selenide oxide mentioned in the present application is as follows:

[0078] The PPC solution is spin-coated on the surface of the two-dimensional bismuth selenide oxide to form a PPC layer, the spin-coating speed is 1000-10000 rpm, preferably 2000-6000 rpm, and the baking temperature is 50-120℃, preferably 60-80℃.

[0079] The spin coating speed can be, for example, 1000 rpm, 3000 rpm, 5000 rpm, 8000 rpm, 10000 rpm, or any range formed by any of the above values. The baking temperature can be, for example, 50 DEG C, 80 DEG C, 100 DEG C, 120 DEG C, or any range formed by any of the above values.

[0080] In the embodiment, the solvent of the PPC solution mentioned in S2 can be anisole, and the concentration of the PPC solution can be 2-6 wt%, for example, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, or any range formed by any of the above values.

[0081] In the embodiment, the specific process parameters for spin coating the PPC are as follows:

[0082] The solvent of the PPC solution is anisole, the concentration of the PPC solution is 4 wt%, the spin coating speed is 2000 rpm, and the baking temperature is 80 DEG C.

[0083] In the embodiment, the forming method of the PDMS layer mentioned in S2 can be roll bonding.

[0084] In the embodiment, the heating temperature for releasing the PDMS mentioned in S2 is 160-200 DEG C, for example, 160 DEG C, 170 DEG C, 180 DEG C, 190 DEG C, 200 DEG C, or any range formed by any of the above values.

[0085] In the embodiment, the specific heating temperature for releasing the TRT mentioned in S2 is 90-150 DEG C, preferably 100-120 DEG C, for example, 90 DEG C, 100 DEG C, 110 DEG C, 120 DEG C, 130 DEG C, 140 DEG C, 150 DEG C, or any range formed by any of the above values.

[0086] In the embodiment, the organic solvent used for removing the PPC after baking mentioned in S2 can be, for example, acetone or N-methyl pyrrolidone with UP grade or HPLC purity, the baking temperature is preferably 150 DEG C, and the baking time is 15 min.

[0087] The selenium bismuth oxide film transferred by the method for transferring a two-dimensional selenium bismuth oxide film is complete and continuous, the surface roughness is 0.63 nm, a two-inch clean selenium bismuth oxide wafer can be obtained, and the one-time large-area transfer of the two-dimensional selenium bismuth oxide film can be realized, and the transfer efficiency is higher.

[0088] In the specific embodiment, the application further provides a two-dimensional bismuth selenide hetero-integration method, which transfers the two-dimensional bismuth selenide to a target substrate by using the transfer method of the two-dimensional bismuth selenide film provided by the application, so as to realize the hetero-integration of the two-dimensional bismuth selenide.

[0089] In the specific embodiment, the two-dimensional bismuth selenide hetero-integration method of the application is suitable for transferring the two-dimensional bismuth selenide film to a plurality of different target substrates, and thus the hetero-integration of a plurality of different substrates and the two-dimensional bismuth selenide can also be realized, for example, any one of a silicon wafer, a silicon oxide wafer, quartz, sapphire, and a polyethylene terephthalate substrate.

[0090] Embodiment 1

[0091] A transfer method of a two-dimensional bismuth selenide film, as shown in Figure 1 , includes the following steps:

[0092] S1. A 5 nm hafnium oxide layer is grown on the surface of a two-inch two-dimensional bismuth selenide / sapphire wafer by using atomic layer deposition with tetrakis(dimethylamino)hafnium and water as source materials, and the growth temperature is 100°C;

[0093] Then, 500 nm of a stress layer nickel and 1500 nm of a support layer copper are sputtered on the surface of the hafnium oxide layer in sequence by using a magnetron sputtering;

[0094] Then, a thermal release tape (TRT) layer is attached to the surface of the support layer copper by using a roll press, so as to obtain a “TRT / copper / nickel / hafnium oxide / two-dimensional bismuth selenide / sapphire” composite structure;

[0095] S2. The “TRT / copper / nickel / hafnium oxide / two-dimensional bismuth selenide” composite structure is separated from the sapphire by using a mechanical dry peeling method (the morphology of the two-dimensional bismuth selenide after separation is shown in Figure 2 );

[0096] Commercially available polypropylene carbonate (weight average molecular weight 200-300 million) is dissolved in anisole with a mass fraction of 4wt%, and the PPC is uniformly spin-coated on the surface of the two-dimensional bismuth selenide by using a spin coater at a speed of 2000 rpm, and then baked on a hot table at 80°C for 3 min for solidification;

[0097] The PDMS is attached to the surface of the PPC by using a roll press, then the TRT is released on a hot table at 120°C, then the metal (copper / nickel layer) is completely etched by using a 1 mol / L ferric chloride solution, and then the deionized water is used for cleaning 5 times, each time for 10 min;

[0098] Finally, the "PDMS / PPC / two-dimensional bismuth selenide oxide / hafnium oxide" is attached to the surface of the silicon / silicon oxide substrate using a roller press, the PDMS is released on a hot stage at 180°C, and then the PPC is removed using acetone to obtain two-dimensional bismuth selenide oxide / hafnium oxide / silicon / silicon oxide, and the morphology of the transferred two-dimensional bismuth selenide oxide is shown in Figure 2 .

[0099] The transferred two-dimensional bismuth selenide oxide film Figure 3 is shown, and it can be seen that the surface is smooth, clean and uniform, and the surface roughness statistics show that the surface roughness is less than 0.65 nm. Figure 4 is the Raman spectrum of the transferred bismuth selenide oxide film, and the Raman spectrum shows that the transferred film is uniform.

[0100] The electrical properties of the transferred two-dimensional bismuth selenide oxide film are shown in Figure 5 , and a field effect transistor (FET) is prepared using standard micro-nano processing techniques such as electron beam exposure Figure 5 embedded diagram), and the results show that the electrical properties of the transferred two-dimensional bismuth selenide oxide film are excellent, and the electron mobility can reach 150 cm 2 V -1 s -1 .

[0101] Example 2

[0102] A transfer method of a two-dimensional bismuth selenide oxide film is shown in Figure 1 , and includes the following steps:

[0103] S1. A 5nm hafnium oxide layer is grown on the surface of a two-inch two-dimensional bismuth selenide oxide / sapphire wafer (two-dimensional bismuth selenide oxide film thickness of 10nm) using atomic layer deposition method with tetrakis(dimethylamino)hafnium and water as source materials, and the growth temperature is 100°C;

[0104] Then, 500nm stress layer nickel and 1500nm support layer copper are sputtered on the surface of the hafnium oxide layer in turn using a magnetron sputtering method;

[0105] Then, the thermal release tape (TRT) layer is attached to the surface of the support layer copper using a roller press to obtain a "TRT / copper / nickel / hafnium oxide / two-dimensional bismuth selenide oxide / sapphire" composite structure;

[0106] S2. The "TRT / copper / nickel / hafnium oxide / two-dimensional bismuth selenide oxide" composite structure is separated from the sapphire using a mechanical dry peeling method, and the two-dimensional bismuth selenide oxide / hafnium oxide / silicon / silicon oxide is transferred by referring to the steps of Example 1;

[0107] The peeled sapphire is reused for growing two-dimensional bismuth selenium oxide, and the same process is used for peeling, and the two-dimensional bismuth selenium oxide / hafnium oxide / silicon oxide / silicon is transferred by referring to the steps of Example 1. This method can realize at least three times of repeated growth and peeling, such as Figure 6 It can be seen that the surface is smooth, clean and uniform after multiple growth and peeling.

[0108] Example 3

[0109] A transfer method of a two-dimensional bismuth selenium oxide film, as shown in Figure 1 , comprises the following steps:

[0110] S1. Using atomic layer deposition method, taking hafnium tetrakis (dimethylamino) and water as source materials, growing a 10nm hafnium oxide layer on the surface of a two-inch two-dimensional bismuth selenium oxide / sapphire wafer (the thickness of the two-dimensional bismuth selenium oxide film is 8nm), and the growth temperature is 100℃;

[0111] Then using magnetron sputtering, sputtering 1000nm stress layer nickel and 1000nm support layer copper on the surface of the hafnium oxide layer in turn;

[0112] Then using a rolling machine, the thermal release tape (TRT) layer is attached to the surface of the support layer copper to obtain a "TRT / copper / nickel / hafnium oxide / two-dimensional bismuth selenium oxide / sapphire" composite structure;

[0113] S2. Using mechanical dry peeling method, the "TRT / copper / nickel / hafnium oxide / two-dimensional bismuth selenium oxide" composite structure is separated from the sapphire, and the two-dimensional bismuth selenium oxide / hafnium oxide / silicon oxide / silicon is transferred by referring to the steps of Example 1.

[0114] As shown in Figure 7 , the transferred two-dimensional bismuth selenium oxide film is continuous, complete and clean, which indicates the reliability of the method.

[0115] Comparative Example 1

[0116] A transfer method of a two-dimensional bismuth selenium oxide film, comprising the following steps:

[0117] S1. Using magnetron sputtering, sputtering 300nm metal nickel on the surface of a two-inch two-dimensional bismuth selenium oxide / sapphire wafer (the thickness of the two-dimensional bismuth selenium oxide film is 10nm), then using a rolling machine, the thermal release tape (TRT) is attached to the surface of the metal nickel, and the "TRT / nickel / two-dimensional bismuth selenium oxide" composite structure is separated from the sapphire by using mechanical dry peeling method, as shown in Figure 8 .

[0118] A commercially available polypropylene carbonate (weight average molecular weight 200-300 million) was dissolved in anisole at a mass fraction of 4wt%, and a uniform spin coating of PPC was performed on the surface of two-dimensional bismuth selenide oxide using a spin coater at a speed of 2000 rpm. The sample was baked on a hot plate at 80°C for 3 min for curing. A PDMS was attached to the surface of the PPC using a roller press. The TRT was then released on a hot plate at 120°C. The metal was completely etched using a 1 mol / L ferric chloride solution, and deionized water was used for cleaning 5 times, each for 10 min. Finally, the "PDMS / PPC / two-dimensional bismuth selenide oxide" was attached to the surface of a silicon / silicon oxide substrate using a roller press. The PDMS was released on a hot plate at 180°C. The PPC was then removed using acetone to obtain a two-dimensional bismuth selenide oxide / silicon / silicon oxide, as shown in Figure 8 .

[0119] As can be seen from Figure 8 , the surface of the two-dimensional bismuth selenide oxide film after peeling in the transfer method has cracks and part of the area is damaged by the etching solution after transfer. A two-dimensional bismuth selenide oxide film with a smooth, clean and uniform surface cannot be obtained. The quality of the two-dimensional bismuth selenide oxide is damaged, which seriously affects its electrical properties.

[0120] Comparative Example 2

[0121] A transfer method of a two-dimensional bismuth selenide oxide film, as shown in Figure 1 , comprises the following steps:

[0122] S1. A 25 nm hafnium oxide layer was grown on the surface of a two-inch two-dimensional bismuth selenide oxide / sapphire wafer (two-dimensional bismuth selenide oxide film thickness of 10 nm) by atomic layer deposition using tetrakis(dimethylamino)hafnium and water as source materials, and the growth temperature was 100°C.

[0123] Then, 800 nm of a stress layer of nickel and 2000 nm of a support layer of copper were sputtered in sequence on the surface of the hafnium oxide layer using a magnetron sputtering.

[0124] Then, a thermal release tape (TRT) layer was attached to the surface of the support layer of copper using a roller press to obtain a "TRT / copper / nickel / hafnium oxide / two-dimensional bismuth selenide oxide / sapphire" composite structure.

[0125] S2. The "TRT / copper / nickel / hafnium oxide / two-dimensional bismuth selenide oxide" composite structure was separated from the sapphire by a mechanical dry peeling method. A two-dimensional bismuth selenide oxide / hafnium oxide / silicon oxide / silicon was obtained by the transfer method according to the steps of Reference Example 1.

[0126] As shown in Figure 9As shown, the 800 nm stress layer and the 2000 nm support layer can realize the nondestructive peeling of the two-dimensional bismuth selenide oxide, but the two-dimensional bismuth selenide oxide after transfer has macroscopic damage and a large number of micro cracks, because the 25 nm thick hafnium oxide increases the rigidity of the composite film, the two-dimensional bismuth selenide oxide cannot conform to the target substrate, and then leads to damage.

[0127] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for transferring a two-dimensional bismuth oxy selenide film, characterized by, The method comprises the following steps: S1. sequentially forming an oxide layer, a stress layer, a support layer and a TRT layer on the surface of a two-dimensional bismuth selenide oxide film to obtain a composite structure of TRT layer / support layer / stress layer / oxide layer / two-dimensional bismuth selenide oxide / growth substrate; S2. peeling the TRT / support layer / stress layer / oxide layer / two-dimensional bismuth selenide oxide from the surface of the growth substrate, and then transferring the two-dimensional bismuth selenide oxide to a target substrate; The thickness of the oxide layer is 2-20 nm; The thickness of the stress layer is 300-2000 nm; The thickness of the support layer is 1000-3000 nm; The oxide of the oxide layer in S1 is hafnium oxide and / or aluminum oxide; The stress layer in S1 is any one of a Cr layer, a Mo layer, a Pt layer and a Ni layer, and the support layer is an Au layer, an Ag layer or a Cu layer.

2. The method of claim 1, wherein the two-dimensional bismuth oxy selenide film is transferred by a method comprising: The oxide layer in S1 is formed by any one of the following methods: (1) atomic layer deposition, the deposition source of the atomic layer deposition is tetra (dimethylamino) hafnium, trimethylaluminum and water, and the growth temperature is 100-250°C; (2) electron beam evaporation, the deposition rate is 0.1-5 Å / s.

3. The method of claim 1 or 2, wherein the two-dimensional bismuth oxy selenide film is transferred by a method comprising: The specific operation of transferring the two-dimensional bismuth selenide oxide to the target substrate in S2 is as follows: After the two-dimensional bismuth selenide oxide is peeled from the surface of the growth substrate, a PPC layer and a PDMS layer are sequentially formed on the surface of the two-dimensional bismuth selenide oxide to obtain a structure of TRT layer / support layer / stress layer / oxide layer / two-dimensional bismuth selenide oxide / PPC / PDMS, and then the TRT layer and the support layer / stress layer are removed, the two-dimensional bismuth selenide oxide is attached to the target substrate through the PDMS layer, and then the PDMS layer and the PPC layer are removed to transfer the two-dimensional bismuth selenide oxide to the target substrate.

4. The method of claim 3, wherein the two-dimensional bismuth oxy selenide film is transferred by a method comprising: The support layer / stress layer is removed by etching with a ferric chloride solution.

5. The method of claim 4, wherein the two-dimensional bismuth oxy selenide film is transferred by, The etching concentration of the ferric chloride solution etching is 0.5-2 mol / L, and the etching time is 1-5 min.

6. The method of claim 3, wherein the two-dimensional bismuth oxy selenide film is transferred by a method comprising: The PPC layer on the surface of the two-dimensional bismuth selenide oxide is formed by the following method: A PPC solution is spin-coated on the surface of the two-dimensional bismuth selenide oxide to form a PPC layer, the spin-coating rotation speed is 1000-10000 rpm, and the baking and gelation temperature is 50-120°C.

7. A method of hetero-integration of two-dimensional bismuth oxy selenide, characterized in that, The two-dimensional bismuth selenide oxide is transferred to the target substrate by the method for transferring the two-dimensional bismuth selenide oxide film according to any one of claims 1-6, so as to realize the heterogeneous integration of the two-dimensional bismuth selenide oxide.

8. The method of claim 7, wherein the two-dimensional BiOX is selected from the group consisting of BiOCl, BiOBr, and BiOJ. The target substrate comprises any one of a silicon wafer, a silicon oxide wafer, quartz and a polyethylene terephthalate substrate.

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