Thin film transistor based on two-dimensional semiconductor material and preparation method thereof
By forming a oxidized easily oxidized two-dimensional semiconductor material in situ on the two-dimensional semiconductor material, the problem of high defect density in the semiconductor-oxide interface in the prior art is solved, and the interface with low defect density is achieved, and the performance of the two-dimensional transistor is improved.
Patent Information
- Application Number
- CN202411740348.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-29
- Publication Date
- 2025-02-28
AI Technical Summary
The prior art is difficult to form high-quality dense oxides on the surface of two-dimensional semiconductor materials, resulting in high defect density of semiconductor-oxide interfaces, limiting the performance of two-dimensional transistors.
By in situ oxidizing on the two-dimensional semiconductor material, an oxidizing two-dimensional semiconductor material is formed to form a semiconductor-oxide interface with low defect density. The specific step includes sequentially preparing the semiconductor active layer and a first insulating dielectric layer on the substrate, and the first insulating dielectric layer is formed from in situ oxidizing two-dimensional semiconductor material.
The defect density of the interface is greatly reduced, the quality of the interface is improved, and thus the performance of transistor devices based on two-dimensional semiconductor materials is improved.
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Figure CN119545866A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of semiconductor devices, and in particular to a thin film transistor based on two-dimensional semiconductor materials and a preparation method thereof. Background Art
[0002] Since the invention of integrated circuits in the late 1950s, silicon has been the main semiconductor material in the field of microelectronics due to its advantages such as suitable band gap, high chemical stability and native oxide SiO2 with good interface. As the channel size of devices continues to shrink, silicon-based devices face problems such as mobility and short channel effects, and Moore's Law is approaching its physical limit.
[0003] Two-dimensional semiconductor materials are considered to be one of the most promising candidates for breaking through the limits of silicon due to their ultra-thin atomic layered structures and unique physical properties. In the past period of time, scientists have made significant progress in scaling the size of two-dimensional transistors using two-dimensional materials and their heterostructures, reducing the physical gate length of transistors from microns to sub-1 nanometer, achieving the continuation of Moore's Law.
[0004] A high-quality, low-defect-density semiconductor-oxide interface is the basis for realizing high-performance transistors. According to the theoretical model evaluation of the Boltzmann transport equation and Fermi's golden rule, two-dimensional materials can minimize the scattering effect and ensure mobility at atomic-scale thickness with their passivated surface without dangling bonds. However, due to the absence of dangling bonds on the surface, it is difficult to form high-quality dense oxides on the surface of two-dimensional semiconductor materials through traditional coating methods during the preparation of transistor devices. Therefore, it is difficult to achieve a semiconductor-oxide interface with low defect density, which has a great impact on the performance of two-dimensional transistors and limits the development of semiconductor integrated circuits based on two-dimensional materials. Summary of the invention
[0005] In view of this, an object of the present invention is to provide a thin film transistor based on two-dimensional semiconductor materials with a semiconductor-oxide interface having a low defect density and a method for preparing the same.
[0006] In order to solve the above problems, the first aspect of the present invention is to provide a thin film transistor based on a two-dimensional semiconductor material, comprising a semiconductor active layer, a first insulating dielectric layer and a gate electrode sequentially arranged on a substrate, wherein the material of the semiconductor active layer is a two-dimensional semiconductor material, and the first insulating dielectric layer is formed by in-situ oxidation of an easily oxidizable two-dimensional semiconductor material connected to the semiconductor active layer; wherein,
[0007] The chemical formula of the easily oxidizable two-dimensional semiconductor material is composed of an A element and a B element, wherein the A element is selected from one or more of Zr, Hf, Ta, Bi and Y elements, and the B element is selected from one or more of S, Se and Te elements; the chemical formula of the material of the first insulating dielectric layer formed by in-situ oxidation is AO x , x>0; or,
[0008] The chemical formula of the easily oxidizable two-dimensional semiconductor material is composed of the A element, the B element and the O element, and the chemical formula of the material of the first insulating dielectric layer formed by in-situ oxidation is ABO y , y>0.
[0009] Preferably, the material of the semiconductor active layer adopts the easily oxidizable two-dimensional semiconductor material, the first insulating dielectric layer is formed by in-situ oxidation of the top portion of the semiconductor active layer, and the first insulating dielectric layer and the semiconductor active layer are an integrally connected structure.
[0010] Preferably, a first semiconductor layer and a second semiconductor layer are sequentially arranged on the substrate, the first semiconductor layer is made of a two-dimensional semiconductor material different from the easily oxidizable two-dimensional semiconductor material, and the second semiconductor layer is made of the easily oxidizable two-dimensional semiconductor material;
[0011] The first insulating dielectric layer is formed by in-situ oxidation of the entire second semiconductor layer, and the first semiconductor layer is formed as the semiconductor active layer; or, the first insulating dielectric layer is formed by in-situ oxidation of the top portion of the second semiconductor layer, and the unoxidized portions of the first semiconductor layer and the second semiconductor layer are formed as the semiconductor active layer.
[0012] Preferably, the thin film transistor further comprises a source electrode electrically connected to the first end of the semiconductor active layer and a drain electrode electrically connected to the second end of the semiconductor active layer.
[0013] Preferably, the thickness of the first insulating dielectric layer is 10 nm to 15 nm.
[0014] Preferably, the first insulating dielectric layer is further provided with a second insulating dielectric layer, and the gate electrode is formed on the second insulating dielectric layer.
[0015] Preferably, the material of the second insulating dielectric layer is a metal oxide dielectric material, a High-k dielectric material or a ferroelectric dielectric material.
[0016] In order to solve the above problems, the second aspect of the present invention is to provide a method for preparing a thin film transistor based on a two-dimensional semiconductor material as described above, comprising:
[0017] Providing the substrate, and sequentially preparing a first semiconductor layer and a second semiconductor layer on the substrate, wherein the second semiconductor layer is made of the easily oxidizable two-dimensional semiconductor material, and the first semiconductor layer is made of the same or different two-dimensional semiconductor material as the second semiconductor layer;
[0018] The second semiconductor layer is completely oxidized in situ by an oxidation process to form the first insulating dielectric layer, and the first semiconductor layer is formed as the semiconductor active layer; or the top portion of the second semiconductor layer is oxidized in situ by an oxidation process to form the first insulating dielectric layer, and the first semiconductor layer and the unoxidized portion of the second semiconductor layer are formed together as the semiconductor active layer;
[0019] The gate electrode is formed on the first insulating dielectric layer.
[0020] Specifically, the first semiconductor layer uses the same easily oxidizable two-dimensional semiconductor material as the second semiconductor layer, and the first semiconductor layer and the second semiconductor layer are an integrated structure that is prepared and formed simultaneously.
[0021] Specifically, the first semiconductor layer and the second semiconductor layer are directly prepared and formed on the substrate, or the first semiconductor layer and / or the second semiconductor layer are first prepared and formed on another substrate and then peeled and transferred to the substrate; the oxidation process is a thermal oxidation process, an oxygen plasma oxidation process, or an ultraviolet ozone oxidation process.
[0022] The method for preparing a thin-film transistor based on a two-dimensional semiconductor material provided in an embodiment of the present invention forms a two-dimensional semiconductor-oxide interface by constructing an oxide layer in situ on a two-dimensional semiconductor material, thereby greatly reducing the defect density of the interface and improving the quality of the interface. The oxide dielectric layer can be directly used as the gate dielectric layer of the transistor, or the oxide dielectric layer can be used as a transition to further prepare a dense and uniform dielectric film on the oxide dielectric layer by conventional coating to serve as the gate dielectric layer of the transistor, thereby improving the performance of transistor devices based on two-dimensional semiconductor materials. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 is a schematic structural diagram of a thin film transistor in a first specific embodiment of the present invention;
[0024] Figure 2 is a schematic structural diagram of a thin film transistor in a second specific embodiment of the present invention;
[0025] Figure 3 It is a schematic diagram of the structure of a thin film transistor in the third specific embodiment of the present invention. DETAILED DESCRIPTION
[0026] In order to make the purpose, technical scheme and advantages of the present invention clearer, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. Examples of these preferred embodiments are illustrated in the accompanying drawings. The embodiments of the present invention shown in the accompanying drawings and described according to the accompanying drawings are merely exemplary, and the present invention is not limited to these embodiments.
[0027] It should also be noted that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the solutions according to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.
[0028] The embodiment of the present invention provides a thin film transistor based on a two-dimensional semiconductor material. Figures 1 to 3 The thin film transistor includes a semiconductor active layer 20, a first insulating dielectric layer 30 and a gate electrode 40 sequentially disposed on a substrate 10. Further, the thin film transistor also includes a source electrode 50 electrically connected to a first end of the semiconductor active layer 20 and a drain electrode 60 electrically connected to a second end of the semiconductor active layer 20.
[0029] The semiconductor active layer 20 is made of a two-dimensional semiconductor material, and the first insulating dielectric layer 30 is formed by in-situ oxidation of an easily oxidizable two-dimensional semiconductor material connected to the semiconductor active layer 20, thereby forming a two-dimensional semiconductor-oxide interface.
[0030] The chemical formula of the easily oxidizable two-dimensional semiconductor material is composed of an A element and a B element, wherein the A element is selected from one or more of zirconium (Zr), hafnium (Hf), tantalum (Ta), bismuth (Bi) and yttrium (Y), and the B element is selected from one or more of sulfur (S), selenium (Se) and tellurium (Te); the chemical formula of the material of the first insulating dielectric layer 30 formed by in-situ oxidation is AO x , x>0. Alternatively, the chemical formula of the easily oxidizable two-dimensional semiconductor material is composed of the A element, the B element and the oxygen (O) element, and the chemical formula of the material of the first insulating dielectric layer 30 formed by in-situ oxidation is ABO y , y>0.
[0031] In a first specific embodiment, if Figure 1 As shown, the material of the semiconductor active layer 20 adopts the easily oxidized two-dimensional semiconductor material, and the first insulating dielectric layer 30 is formed by in-situ oxidation of the top part of the semiconductor active layer 20 corresponding to the position of the gate electrode 40, that is, the first insulating dielectric layer 30 and the semiconductor active layer 20 are an integrally connected structure.
[0032] In a second specific embodiment, Figure 2 As shown, the substrate 10 is provided with a first semiconductor layer and a second semiconductor layer in sequence, the material of the first semiconductor layer is a two-dimensional semiconductor material different from the easily oxidized two-dimensional semiconductor material, and the material of the second semiconductor layer is the easily oxidized two-dimensional semiconductor material. The first insulating dielectric layer 30 is formed by in-situ oxidation of the second semiconductor layer, and the first semiconductor layer is formed as the semiconductor active layer 20. It should be noted that in some other embodiments, the top part of the second semiconductor layer may be in-situ oxidized to form the first insulating dielectric layer 30, and at this time, the semiconductor active layer 20 is formed by the first semiconductor layer and the unoxidized part of the second semiconductor layer.
[0033] As described above in the first and second specific embodiments, the gate electrode 40 is directly deposited on the first insulating dielectric layer 30 , that is, the first insulating dielectric layer 30 formed by in-situ oxidation is directly used as the gate dielectric layer of the transistor.
[0034] In a third specific embodiment, Figure 3 As shown, the difference from the above two specific embodiments is that the first insulating dielectric layer 30 is further provided with a second insulating dielectric layer 70, and the gate electrode 40 is formed on the second insulating dielectric layer 70. That is, in the third specific embodiment, the first insulating dielectric layer 30 formed by in-situ oxidation is used as a transition, and a second insulating dielectric layer 70 (dielectric film) with a dense and uniform thickness is further prepared on the first insulating dielectric layer 30 by a conventional coating method as the gate dielectric layer of the transistor.
[0035] The material of the second insulating dielectric layer 70 can be selected from metal oxide dielectric materials, High-k dielectric materials or ferroelectric dielectric materials. The material of the second insulating dielectric layer 70 is preferably an oxide of the element A, so that the second insulating dielectric layer 70 and the first insulating dielectric layer 30 have better bonding performance.
[0036] In the first to third specific embodiments described above, the thickness of the first insulating dielectric layer 30 is preferably 10 nm to 15 nm.
[0037] It should be noted that, in the thin film transistor described above, the specific materials and thicknesses of the substrate 10, the source electrode 50, the drain electrode 60 and the gate electrode 40 can be selected and set according to actual needs with reference to the thin film transistor in the prior art. The substrate 10 is preferably a compound insulator or a multilayer structure with an insulator as the top layer, such as Si / SiO2, mica, glass, etc.
[0038] The present invention also provides a method for preparing a thin film transistor based on a two-dimensional semiconductor material as described above, Figure 1-3 The structural diagram shown in the figure, the preparation method comprises the following steps:
[0039] Step S10 , providing a substrate 10 , and forming a first semiconductor layer on the substrate 10 to obtain the semiconductor active layer 20 .
[0040] Step S20 , forming a source electrode 50 and a drain electrode 60 on the semiconductor active layer 20 .
[0041] Specifically, the source electrode 50 and the drain electrode 60 are disposed on the semiconductor active layer 20 at intervals, the source electrode 50 is connected to a first end of the semiconductor active layer 20 , and the drain electrode 60 is connected to a second end of the semiconductor active layer 20 .
[0042] Step S30 , forming a second semiconductor layer on the semiconductor active layer 20 at a position between the source electrode 50 and the drain electrode 60 , wherein the material of the second semiconductor layer is the easily oxidizable two-dimensional semiconductor material.
[0043] It should be noted that the first semiconductor layer may be made of the same or different two-dimensional semiconductor material as the second semiconductor layer. When the first semiconductor layer is made of the same easily oxidizable two-dimensional semiconductor material as the second semiconductor layer, the first semiconductor layer and the second semiconductor layer are an integrated structure prepared simultaneously and are prepared simultaneously in the above step S10.
[0044] Step S40, performing in-situ oxidation treatment on the second semiconductor layer to form the first insulating dielectric layer 30, includes the following three situations:
[0045] (1) The first semiconductor layer is made of the same easily oxidizable two-dimensional semiconductor material as the second semiconductor layer, and the first semiconductor layer and the second semiconductor layer are an integrated structure formed simultaneously. The top portion of the semiconductor layer of the integrated structure corresponding to the position of the gate electrode 40 is in-situ oxidized by an oxidation process to form the first insulating dielectric layer 30, and the unoxidized semiconductor layer is formed as the semiconductor active layer 20 (corresponding to Figure 1 transistor structure shown).
[0046] (2) The first semiconductor layer and the second semiconductor layer are made of different materials. The top portion of the second semiconductor layer is in-situ oxidized by an oxidation process to form the first insulating dielectric layer 30. The unoxidized portions of the first semiconductor layer and the second semiconductor layer together form the semiconductor active layer 20.
[0047] (3) The first semiconductor layer and the second semiconductor layer are made of different materials. The second semiconductor layer is completely oxidized in situ by an oxidation process to form the first insulating dielectric layer 30. The first semiconductor layer is formed into the semiconductor active layer 20 (corresponding to Figure 2 transistor structure shown).
[0048] Step S50: Form the gate electrode 40 (corresponding to Figure 1-2 Alternatively, a second insulating dielectric layer 70 is first deposited on the first insulating dielectric layer 30, and then the gate electrode 40 is formed on the second insulating dielectric layer 70 (corresponding to Figure 3 transistor structure shown).
[0049] In the step S10 and the step S30, the first semiconductor layer and the second semiconductor layer can be directly prepared and formed on the substrate 10, or the first semiconductor layer and the second semiconductor layer are first prepared and formed on another substrate and then peeled and transferred to the substrate 10. Specifically, they can be prepared by atomic layer deposition (ALD), molecular beam epitaxy (MBE), metal organic chemical vapor deposition (MOCVD), pulsed laser deposition (PLD), chemical vapor deposition (CVD), chemical vapor transport (CVT) and other processes.
[0050] Wherein, in the step S40, the oxidation process is a thermal oxidation process, an oxygen plasma oxidation process, or an ultraviolet ozone oxidation process.
[0051] Example 1
[0052] (1) The crystalline semiconductor material HfS2 crystal is grown using chemical vapor transport (CVT).
[0053] (2) The layered semiconductor material HfS 2 is transferred onto the Si / SiO 2 substrate 10 using PDMS by mechanical stripping, wherein the thickness of the HfS 2 semiconductor material layer is 30 nm.
[0054] (3) A source electrode 50 and a drain electrode 60 spaced apart from each other are prepared on the HfS 2 semiconductor material layer on the Si / SiO 2 substrate 10 using techniques such as electron beam lithography and thermal evaporation deposition.
[0055] (4) The Si / SiO2 substrate containing the HfS2 semiconductor material layer is placed on a hot plate and directly heated for in-situ oxidation, and the upper surface portion of the HfS2 semiconductor material layer is in-situ oxidized to be converted into a HfO2 insulating dielectric layer 30, wherein the thickness of the HfO2 insulating dielectric layer is 15 nm, and the bottom unoxidized HfS2 semiconductor material layer is formed into a semiconductor active layer 20. The thermal oxidation temperature is 300° C. and the time is 10 min.
[0056] (5) A gate electrode 40 is formed by depositing the gate electrode 40 on the HfO2 insulating dielectric layer 30 to obtain a Figure 1 A thin film transistor with the structure shown.
[0057] Example 2
[0058] (1) A MoS2 semiconductor material layer is grown on the surface of the Si / SiO2 substrate 10 by chemical vapor deposition (CVD) to form a semiconductor active layer 20 with a thickness of 5 nm.
[0059] (2) Electron beam lithography, thermal evaporation deposition and other techniques are used to prepare a source electrode 50 and a drain electrode 60 spaced apart from each other on a MoS2 semiconductor material layer (semiconductor active layer 20) on a Si / SiO2 substrate.
[0060] (3) A crystalline semiconductor material HfS2 crystal is grown by chemical vapor transport (CVT), and the layered semiconductor material HfS2 is transferred to the semiconductor active layer 20 of step (2) by mechanical peeling using PDMS, and connected to the position between the source electrode 50 and the drain electrode 60, wherein the thickness of the HfS2 semiconductor material layer is 10 nm.
[0061] (4) The sample obtained in step (3) is placed in an ozone treatment device for oxidation treatment, and the HfS2 material layer is completely oxidized and converted into the HfO2 insulating dielectric layer 30. The power of the ozone oxidation treatment is 200 W and the time is 20 min.
[0062] (5) A gate electrode 40 is formed by depositing the gate electrode 40 on the HfO2 insulating dielectric layer 30 to obtain a Figure 2 A thin film transistor with the structure shown.
[0063] Example 3
[0064] (1) Chemical vapor transport (CVT) was used to grow MoS2 and ZrSe2 crystals.
[0065] (2) The layered semiconductor material MoS 2 is transferred onto the Si / SiO 2 substrate 10 using PDMS by mechanical exfoliation, and the layered semiconductor material MoS 2 is formed into a semiconductor active layer 20 .
[0066] (3) Electron beam lithography, thermal evaporation deposition and other techniques are used to prepare a source electrode 50 and a drain electrode 60 spaced apart from each other on a MoS2 semiconductor material layer (semiconductor active layer 20) on a Si / SiO2 substrate.
[0067] (4) Using PDMS by mechanical stripping, the layered semiconductor material ZrSe2 is transferred to the semiconductor active layer 20 of step (3) and connected to the position between the source electrode 50 and the drain electrode 60, wherein the thickness of the ZrSe2 semiconductor material layer is 15 nm.
[0068] (5) The sample obtained in step (4) is placed in an oxygen plasma treatment device for oxidation treatment, and the ZrSe2 semiconductor material layer is completely oxidized and converted into a ZrO2 insulating dielectric layer 30. The power of the oxygen plasma treatment is 300 W, and the time is 30 min.
[0069] (6) The HfO 2 dielectric material is further deposited on the ZrO 2 insulating dielectric layer 30 using an ALD deposition process to form a HfO 2 insulating dielectric layer 70 , wherein the thickness of the HfO 2 is 15 nm.
[0070] (7) A gate electrode 40 is formed by depositing the gate electrode 40 on the HfO2 insulating dielectric layer 70 to obtain a Figure 3 A thin film transistor with the structure shown.
[0071] It should be pointed out that the above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.
Claims
1. A thin film transistor based on two-dimensional semiconductor material, characterized in that: It comprises a semiconductor active layer, a first insulating dielectric layer and a gate electrode which are sequentially arranged on a substrate, wherein the material of the semiconductor active layer is a two-dimensional semiconductor material, and the first insulating dielectric layer is formed by in-situ oxidation of an easily oxidizable two-dimensional semiconductor material connected to the semiconductor active layer; wherein, The chemical formula of the easily oxidizable two-dimensional semiconductor material is composed of an A element and a B element, wherein the A element is selected from one or more of Zr, Hf, Ta, Bi and Y elements, and the B element is selected from one or more of S, Se and Te elements; the chemical formula of the material of the first insulating dielectric layer formed by in-situ oxidation is AO x , x>0; or, The chemical formula of the easily oxidizable two-dimensional semiconductor material is composed of the A element, the B element and the O element, and the chemical formula of the material of the first insulating dielectric layer formed by in-situ oxidation is ABO y , y>0.
2. The thin film transistor based on two-dimensional semiconductor material according to claim 1, characterized in that: The material of the semiconductor active layer adopts the easily oxidizable two-dimensional semiconductor material, the first insulating dielectric layer is formed by in-situ oxidation of the top part of the semiconductor active layer, and the first insulating dielectric layer and the semiconductor active layer are an integrally connected structure.
3. The thin film transistor based on two-dimensional semiconductor material according to claim 1, characterized in that: A first semiconductor layer and a second semiconductor layer are sequentially arranged on the substrate, wherein the material of the first semiconductor layer is a two-dimensional semiconductor material different from the easily oxidizable two-dimensional semiconductor material, and the material of the second semiconductor layer is the easily oxidizable two-dimensional semiconductor material; The first insulating dielectric layer is formed by completely in-situ oxidation of the second semiconductor layer, and the first semiconductor layer is formed as the semiconductor active layer; Alternatively, the first insulating dielectric layer is formed by in-situ oxidation of a top portion of the second semiconductor layer, and unoxidized portions of the first semiconductor layer and the second semiconductor layer form the semiconductor active layer.
4. The thin film transistor according to claim 1 is based on a two-dimensional semiconductor material, characterized in that: The thin film transistor further includes a source electrode electrically connected to the first end of the semiconductor active layer and a drain electrode electrically connected to the second end of the semiconductor active layer.
5. The thin film transistor based on two-dimensional semiconductor material according to any one of claims 1 to 4, characterized in that: The thickness of the first insulating dielectric layer is 10 nm to 15 nm.
6. The thin film transistor based on two-dimensional semiconductor material according to claim 5, characterized in that: The first insulating dielectric layer is further provided with a second insulating dielectric layer, and the gate electrode is formed on the second insulating dielectric layer.
7. The thin film transistor based on two-dimensional semiconductor material according to claim 6, characterized in that: The material of the second insulating dielectric layer is a metal oxide dielectric material, a High-k dielectric material or a ferroelectric dielectric material.
8. A method for preparing a thin film transistor based on a two-dimensional semiconductor material according to any one of claims 1 to 7, characterized in that: include: Providing the substrate, and sequentially preparing a first semiconductor layer and a second semiconductor layer on the substrate, wherein the second semiconductor layer is made of the easily oxidizable two-dimensional semiconductor material, and the first semiconductor layer is made of the same or different two-dimensional semiconductor material as the second semiconductor layer; The second semiconductor layer is completely oxidized in situ by an oxidation process to form the first insulating dielectric layer, and the first semiconductor layer is formed into the semiconductor active layer; Alternatively, an oxidation process is used to in-situ oxidize the top portion of the second semiconductor layer to form the first insulating dielectric layer, and the first semiconductor layer and the unoxidized portion of the second semiconductor layer together form the semiconductor active layer; The gate electrode is formed on the first insulating dielectric layer.
9. The preparation method based on two-dimensional semiconductor materials according to claim 8, characterized in that: The first semiconductor layer uses the same easily oxidizable two-dimensional semiconductor material as the second semiconductor layer, and the first semiconductor layer and the second semiconductor layer are an integrated structure that is prepared and formed simultaneously.
10. The preparation method based on two-dimensional semiconductor material according to claim 8 or 9, characterized in that: The first semiconductor layer and the second semiconductor layer are directly prepared and formed on the substrate, or the first semiconductor layer and / or the second semiconductor layer are first prepared and formed on another substrate and then peeled and transferred to the substrate; the oxidation process is a thermal oxidation process, an oxygen plasma oxidation process, or an ultraviolet ozone oxidation process.