Wafer-level transition metal chalcogenides and their preparation apparatus and methods

Abstract

This application relates to a wafer-level transition metal chalcogenide (TMC) and its preparation method and apparatus. In the wafer-level TMC preparation apparatus of this application, the support sites for supporting the substrate are positioned higher than the first and second source support surfaces in the vertical direction. Using this wafer-level TMC preparation apparatus, the inhomogeneity of the chalcogenide source and transition metal source on the substrate surface can be reduced. Simultaneously, the wafer-level TMC preparation method of this application utilizes the aforementioned apparatus, allowing the source to be transported to the substrate surface in the vertical direction against gravity, effectively solving the problem of poor uniformity in the preparation of large-size wafer-level TMCs. Furthermore, multi-wafer batch growth can be achieved by increasing the number of substrate support sites.

Description

Technical Field

[0001] This application relates to the field of two-dimensional materials technology, and in particular to a wafer-level transition metal chalcogenide compound and its preparation apparatus and method. Background Art

[0002] Two-dimensional transition metal chalcogenides (TMDCs) possess excellent physicochemical properties such as atomic layer thickness, high carrier mobility, and ultrafast charge transfer, showing broad development prospects in fields such as ultimate size field-effect transistors, wearable electronic devices, and flexible display devices. Currently, chemical vapor deposition (CVD) technology is considered the most effective means to prepare high-quality wafer-level TMDCs.

[0003] Due to the poor diffusion capabilities of the growth precursors, traditional methods for preparing two-dimensional transition metal chalcogenides (TMCs) using lateral CVD systems, where the source travels parallel to the substrate surface, result in poor uniformity when preparing large-scale wafer-level TMCs. Furthermore, traditional methods struggle to achieve large-scale wafer-level TMC preparation, typically resulting in wafers smaller than 4 inches. Summary of the Invention

[0004] Therefore, it is necessary to provide a wafer-level transition metal chalcogenide compound and its preparation apparatus and method. The wafer-level transition metal chalcogenide compound preparation apparatus of this application can achieve good uniformity in the preparation of wafer-level transition metal chalcogenides and realize the preparation of large-size wafer-level transition metal chalcogenides of 4 inches or larger.

[0005] In a first aspect, this application provides an apparatus for preparing wafer-level transition metal chalcogenides, comprising:

[0006] Reaction chamber;

[0007] A first source support tube and a second source support tube are disposed inside the reaction chamber. The first source support tube has a first source support surface for supporting a chalcogenide source, and the second source support tube has a second source support surface for supporting a transition metal source.

[0008] A first air inlet pipe and a second air inlet pipe, both of which penetrate the reaction chamber; the first air inlet pipe is connected to the first source support pipe to provide vertically upward gas to the first source support pipe, and the second air inlet pipe is connected to the second source support pipe to provide vertically upward gas to the second source support pipe;

[0009] A hollow support frame disposed inside the reaction chamber has a support position for supporting the substrate; in the vertical direction, the position of the support position is higher than the first source support surface and the second source support surface.

[0010] In some embodiments, there are multiple first source support tubes, which are evenly distributed in a ring with equal spacing.

[0011] In some embodiments, there are multiple second source support tubes, which are evenly distributed in a ring with equal spacing.

[0012] In some embodiments, the second source support surface is positioned higher than the first source support surface in the vertical direction.

[0013] In some embodiments, the support frame has a plurality of support positions spaced apart in the vertical direction.

[0014] In some embodiments, the number of the second source support tubes is greater than or equal to the number of the first source support tubes.

[0015] In some embodiments, the ratio of the distance between the support position and the second source support surface to the distance between the second source support surface and the first source support surface in the vertical direction is (1~3):1.

[0016] In some embodiments, the wafer-level transition metal chalcogenide preparation apparatus further includes a temperature control device disposed around the reaction chamber, the temperature control device being used to control the temperature of the first source support tube, the second source support tube, and the support frame.

[0017] Secondly, this application provides a method for preparing wafer-level transition metal chalcogenides using the apparatus for preparing wafer-level transition metal chalcogenides as described in any one of the above claims, comprising the following steps:

[0018] Provide a substrate and place the substrate on the support frame;

[0019] Evaporate the chalcogenide source located on the first source support surface and the transition metal source located on the second source support surface;

[0020] Vertically upward gas is supplied through the first and second air inlets to carry the evaporated chalcogenide source and the transition metal source to the substrate, and a transition metal chalcogenide compound is epitaxially grown on the surface of the substrate.

[0021] In some embodiments, evaporating the chalcogenide source located in the first source support tube includes controlling the temperature of the first source support tube to be 80°C to 300°C.

[0022] In some embodiments, evaporating the transition metal source located in the second source support tube includes controlling the temperature of the second source support tube to be 450°C to 850°C.

[0023] In some embodiments, epitaxial growth of a transition metal chalcogenide on the surface of the substrate includes controlling the temperature of the substrate to be 750°C to 1000°C.

[0024] In some embodiments, the chalcogen source includes at least one of elemental sulfur, elemental selenium, and elemental tellurium.

[0025] In some embodiments, the transition metal source includes at least one of molybdenum oxide, molybdenum chloride, molybdenum inorganic salt compound, tungsten oxide, tungsten chloride, tungsten inorganic salt compound, niobium oxide, niobium chloride, niobium inorganic salt compound, rhenium oxide, rhenium chloride, and rhenium inorganic salt compound.

[0026] In some embodiments, the substrate includes one of a single-crystal sapphire substrate, a single-crystal gold substrate, a single-crystal mica substrate, and a silicon substrate.

[0027] In some embodiments, providing vertically upward gas through the first intake pipe and the second intake pipe includes:

[0028] A first protective gas is introduced through the first intake pipe, and a second protective gas or a mixture of the second protective gas and oxygen is introduced through the second intake pipe.

[0029] In some embodiments, the first protective gas includes at least one of nitrogen and argon.

[0030] In some embodiments, the flow rate of the first protective gas is 100 sccm to 500 sccm.

[0031] In some embodiments, the second protective gas includes at least one of nitrogen and argon.

[0032] In some embodiments, the flow rate of the second protective gas is 50 sccm to 200 sccm.

[0033] In some embodiments, the oxygen flow rate is 0 sccm to 30 sccm.

[0034] In some embodiments, the gas pressure for epitaxial growth is 0.1 Torr to 10 Torr.

[0035] In some embodiments, the epitaxial growth time is 10s to 4200s.

[0036] Thirdly, this application provides a wafer-level transition metal chalcogenide compound, which is prepared by any of the methods described above for preparing wafer-level transition metal chalcogenides.

[0037] In the aforementioned wafer-level transition metal chalcogenide (TMC) fabrication apparatus, the support positions of the support frame for supporting the substrate are vertically higher than the first and second source support surfaces. In practical use, vertically upward gas is supplied through the first and second inlet pipes, allowing control of the transport direction of the chalcogen source and transition metal source to be vertically upward. Simultaneously, the substrate supported by the hollow support frame can receive the gaseous chalcogen source and transition metal source transported vertically upward to the substrate. In conventional wafer-level TMC fabrication methods, the chalcogen source and transition metal source are transported horizontally. During transport, a concentration gradient easily exists along the vertical direction, affecting the growth uniformity of the substrate surface. As the substrate size increases, the uniformity of TMC fabrication gradually decreases. Using this wafer-level TMC fabrication apparatus, the non-uniformity of the chalcogen source and transition metal source on the substrate surface can be reduced, thereby enabling the fabrication of large-size wafer-level TMCs. Attached Figure Description

[0038] Figure 1 A schematic diagram of the structure of a wafer-level transition metal chalcogenide preparation apparatus provided in an embodiment of this application;

[0039] Figure 2 This is a schematic diagram of the structure in Embodiment 1 of this application, showing the substrate placed on the support frame;

[0040] Figure 3 This is a schematic diagram of the 8-inch monolayer molybdenum sulfide wafer prepared in Example 1 of this application;

[0041] Figure 4 This is a partially enlarged schematic diagram of the monolayer molybdenum sulfide film prepared in Example 1 of this application;

[0042] Figure 5 This is an electron microscope image of the monolayer molybdenum sulfide thin film prepared in Example 1 of this application;

[0043] Figure 6 The Raman spectrum of the monolayer molybdenum sulfide thin film prepared in Example 1 of this application is shown.

[0044] Figure 7 The fluorescence spectrum of the monolayer molybdenum sulfide thin film prepared in Example 1 of this application is shown.

[0045] Figure 8The XRD pattern of the monolayer molybdenum sulfide film prepared in Example 1 of this application is the θ-2θ diffraction pattern.

[0046] Figure 9 This is a schematic diagram of the diffraction peaks of molybdenum sulfide and sapphire substrate in the molybdenum sulfide wafer prepared in Example 1 of this application;

[0047] Figure 10 This is a schematic diagram of the simultaneous fabrication of six 4-inch monolayer molybdenum sulfide wafers in Example 2 of this application. Detailed Implementation

[0048] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, a detailed description of specific embodiments of this application is provided below. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0049] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0050] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0051] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0052] In this application, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0053] One embodiment of this application provides a wafer-level apparatus for preparing transition metal chalcogenides, comprising: a reaction chamber; a first source support tube and a second source support tube disposed inside the reaction chamber, the first source support tube having a first source support surface for supporting a chalcogenide source, and the second source support tube having a second source support surface for supporting a transition metal source; a first gas inlet pipe and a second gas inlet pipe, both of which penetrate the reaction chamber; the first gas inlet pipe is connected to the first source support tube to provide vertically upward gas to the first source support tube, and the second gas inlet pipe is connected to the second source support tube to provide vertically upward gas to the second source support tube; and a hollow support frame disposed inside the reaction chamber, the support frame having support positions for supporting a substrate; in the vertical direction, the position of the support positions is higher than the first source support surface and the second source support surface.

[0054] In the aforementioned wafer-level transition metal chalcogenide (TMC) fabrication apparatus, the support positions of the support frame for supporting the substrate are vertically higher than the first and second source support surfaces. In practical use, vertically upward gas is supplied through the first and second inlet pipes, allowing control of the transport direction of the chalcogen source and transition metal source to be vertically upward. Simultaneously, the substrate supported by the hollow support frame can receive the gaseous chalcogen source and transition metal source transported vertically upward to the substrate. In conventional wafer-level TMC fabrication methods, the chalcogen source and transition metal source are transported horizontally. During transport, a concentration gradient easily exists along the vertical direction, affecting the growth uniformity of the substrate surface. As the substrate size increases, the uniformity of TMC fabrication gradually decreases. Using this wafer-level TMC fabrication apparatus, the non-uniformity of the chalcogen source and transition metal source on the substrate surface can be reduced, thereby enabling the fabrication of large-size wafer-level TMCs.

[0055] In some embodiments, there are multiple first source support tubes, which are evenly distributed in a ring with equal spacing.

[0056] Multiple first source support tubes are evenly distributed in a ring with equal spacing, which makes the distribution of gaseous chalcogen sources more uniform, thereby enabling the preparation of wafer-level transition metal chalcogen compounds with high uniformity.

[0057] In some embodiments, there are multiple second source support tubes, which are evenly distributed in a ring with equal spacing.

[0058] Multiple second source support tubes are evenly distributed in a ring with equal spacing, which makes the distribution of gaseous transition metal sources more uniform, thereby enabling the preparation of wafer-level transition metal chalcogenides with high uniformity.

[0059] In some embodiments, the second source support surface is positioned higher than the first source support surface in the vertical direction.

[0060] In the preparation process of wafer-level transition metal chalcogenides, since the melting point of the chalcogen source is lower than that of the transition metal source, the second source support tube is positioned higher than the first source support tube. This facilitates temperature control of the wafer-level transition metal chalcogenide preparation device in the vertical direction, i.e., the temperature of the wafer-level transition metal chalcogenide preparation device is gradually increased from low to high in the vertical direction.

[0061] In some embodiments, the support frame has a plurality of support positions spaced apart in the vertical direction.

[0062] Understandably, multiple support positions spaced apart in the vertical direction can prevent multiple substrates from being used simultaneously for the epitaxial growth of transition metal chalcogenides on multiple substrates.

[0063] In some embodiments, the number of second source support tubes is greater than or equal to the number of first source support tubes.

[0064] In some embodiments, the ratio of the distance between the support position and the second source support surface and the distance between the second source support surface and the first source support surface in the vertical direction is (1~3):1.

[0065] Optionally, the ratio of the distance between the support position and the second source support surface, and the distance between the second source support surface and the first source support surface, can be 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, 2:1, 2.1:1, 2.2:1, 2.3:1, 2.4:1, 2.5:1, 2.6:1, 2.7:1, 2.8:1, 2.9:1, or 3:1. Alternatively, the ratio of the distance between the support position and the second source support surface, and the distance between the second source support surface and the first source support surface, can also be within the range of any two of the above ratios.

[0066] It is understandable that, when there are multiple support points, the ratio of the distance between the support point closest to the second source support surface and the second source support surface to the distance between the second source support surface and the first source support surface is greater than or equal to 1:1, and the ratio of the distance between the support point farthest from the second source support surface and the second source support surface to the distance between the second source support surface and the first source support surface is less than or equal to 3:1.

[0067] In some embodiments, the apparatus for preparing wafer-level transition metal chalcogenides has an exhaust port located vertically above the support frame.

[0068] In some embodiments, the apparatus for preparing wafer-level transition metal chalcogenides further includes a temperature control device disposed around the reaction chamber, which is used to control the temperature of the first source support tube, the second source support tube, and the support frame.

[0069] Another embodiment of this application provides a method for preparing a wafer-level transition metal chalcogenide compound, using the apparatus for preparing a wafer-level transition metal chalcogenide compound according to any one of the above claims, including the following steps:

[0070] Provide a substrate and place it on a support frame;

[0071] Evaporate the chalcogenide source located on the first source support surface and the transition metal source located on the second source support surface;

[0072] Vertically upward gas is supplied through the first and second inlet pipes, carrying the evaporated chalcogenide source and transition metal source to the substrate, and the transition metal chalcogenide compound is epitaxially grown on the surface of the substrate.

[0073] This method utilizes the wafer-level transition metal chalcogenide (TMC) fabrication apparatus described in this application. Through a vertical CVD system, the chalcogenide source and transition metal source are transported vertically against gravity to the substrate surface, effectively solving the problem of poor uniformity in the fabrication of large-size wafer-level TMCs. Furthermore, it allows for batch growth of multiple wafers in a single operation by increasing substrate support sites.

[0074] In some embodiments, the control substrate is placed perpendicular to the direction of gas movement.

[0075] In some of these implementations, the substrate is controlled to be placed horizontally.

[0076] In some embodiments, evaporating the chalcogenide source located in the first source support tube includes controlling the temperature of the first source support tube to be 80°C to 300°C.

[0077] Optionally, evaporating the chalcogen source located in the first source support tube involves controlling the temperature of the first source support tube to 80°C, 100°C, 120°C, 140°C, 160°C, 180°C, 200°C, 220°C, 240°C, 260°C, 280°C, or 300°C. Alternatively, the temperature of the first source support tube may also be within the range of any two of the above temperatures.

[0078] In some embodiments, evaporating the transition metal source located in the second source support tube includes controlling the temperature of the second source support tube to be 450°C to 850°C.

[0079] Optionally, the evaporation of the transition metal source located in the second source support tube includes controlling the temperature of the second source support tube to 450°C, 500°C, 550°C, 600°C, 650°C, 700°C, 750°C, 800°C, or 850°C. Alternatively, the temperature of the second source support tube may also be within the range of any two of the above temperatures.

[0080] In some embodiments, epitaxial growth of transition metal chalcogenides on the surface of a substrate includes controlling the temperature of the substrate to be 750°C to 1000°C.

[0081] Optionally, epitaxially growing a transition metal chalcogenide on the surface of the substrate includes controlling the substrate temperature to 750°C, 800°C, 850°C, 900°C, 950°C, or 1000°C. Alternatively, the substrate temperature may be within the range of any two of the above temperatures.

[0082] In some embodiments, the chalcogen source includes at least one of elemental sulfur, elemental selenium, and elemental tellurium.

[0083] In some embodiments, the sulfide source includes at least one of sulfur powder, selenium powder, and tellurium powder.

[0084] In some embodiments, the transition metal source includes at least one of molybdenum oxide, molybdenum chloride, molybdenum inorganic salt compound, tungsten oxide, tungsten chloride, tungsten inorganic salt compound, niobium oxide, niobium chloride, niobium inorganic salt compound, rhenium oxide, rhenium chloride, and rhenium inorganic salt compound.

[0085] In some embodiments, the substrate includes one of a single-crystal sapphire substrate, a single-crystal gold substrate, a single-crystal mica substrate, and a silicon substrate.

[0086] In some embodiments, supplying vertically upward gas through a first intake pipe and a second intake pipe includes:

[0087] A first protective gas is introduced through a first intake pipe, and a second protective gas or a mixture of the second protective gas and oxygen is introduced through a second intake pipe.

[0088] In some embodiments, the first protective gas includes at least one of nitrogen and argon.

[0089] In some embodiments, the flow rate of the first protective gas is 100 sccm to 500 sccm.

[0090] Optionally, the flow rate of the first protective gas is 100 sccm, 150 sccm, 200 sccm, 250 sccm, 300 sccm, 350 sccm, 400 sccm, 450 sccm, or 500 sccm. Alternatively, the flow rate of the first protective gas may be within any two of the above flow rates.

[0091] In some embodiments, the second protective gas includes at least one of nitrogen and argon.

[0092] In some embodiments, the flow rate of the second protective gas is 50 sccm to 200 sccm.

[0093] Optionally, the flow rate of the second protective gas is 50 sccm, 70 sccm, 90 sccm, 100 sccm, 120 sccm, 140 sccm, 150 sccm, 160 sccm, 180 sccm, or 200 sccm. Alternatively, the flow rate of the second protective gas may be within any two of the above flow rates.

[0094] In some of these embodiments, the oxygen flow rate is 0 sccm to 30 sccm.

[0095] It should be noted that the grain size of the transition metal chalcogenide can be controlled by the oxygen flow rate. Optionally, the oxygen flow rate can be 0 sccm, 2 sccm, 4 sccm, 6 sccm, 8 sccm, 10 sccm, 12 sccm, 14 sccm, 16 sccm, 18 sccm, 20 sccm, 22 sccm, 24 sccm, 26 sccm, 28 sccm, or 30 sccm.

[0096] In some embodiments, the gas pressure for epitaxial growth is 0.1 Torr to 10 Torr.

[0097] Optionally, the gas pressure for epitaxial growth is 0.1 Torr, 0.3 Torr, 0.5 Torr, 0.8 Torr, 1 Torr, 1.5 Torr, 2 Torr, 3 Torr, 4 Torr, 5 Torr, 6 Torr, 7 Torr, 8 Torr, 8.5 Torr, 9 Torr, 9.5 Torr, or 10 Torr. Alternatively, the gas pressure for epitaxial growth can also be within the range of any two of the above gas pressures.

[0098] In some embodiments, the epitaxial growth time is 10s to 4200s.

[0099] Understandably, the growth rates of different transition metal chalcogenides vary considerably depending on the choice of different chalcogen source and different transition metal source. Optionally, the epitaxial growth time is 1200 s to 4200 s. More preferably, the epitaxial growth time is 1200 s, 1400 s, 1600 s, 1800 s, 2000 s, 2200 s, 2400 s, 2600 s, 2800 s, 3000 s, 3200 s, 3400 s, 3600 s, 3800 s, 4000 s, or 4200 s. Alternatively, the epitaxial growth time can also fall within any two of the above time ranges.

[0100] Another embodiment of this application provides a wafer-level transition metal chalcogenide compound, which is prepared by any of the above-described methods for preparing wafer-level transition metal chalcogenides.

[0101] In some embodiments, wafer-level transition metal chalcogenides are epitaxially grown on a substrate.

[0102] In some embodiments, the wafer-level transition metal chalcogenide is a two-dimensional monolayer thin film.

[0103] In some embodiments, the grain size of the wafer-level transition metal chalcogenide is 1 μm to 1000 μm. Optionally, the grain size of the wafer-level transition metal chalcogenide is 1 μm, 2 μm, 5 μm, 10 μm, 20 μm, 50 μm, 100 μm, 200 μm, 500 μm, or 1000 μm. Alternatively, the grain size of the wafer-level transition metal chalcogenide may also be within the range of any two of the above-mentioned grain sizes.

[0104] In some embodiments, the angle between the wafer-level transition metal chalcogenide compound and the substrate is 0° or 30°.

[0105] Example 1

[0106] This embodiment uses Figure 1The wafer-level transition metal chalcogenide preparation apparatus shown is used to epitaxially grow an 8-inch monolayer molybdenum sulfide thin film.

[0107] Preparation method of wafer-level transition metal chalcogenides:

[0108] (1) An 8-inch surface-polished single-crystal sapphire substrate was annealed in an argon atmosphere for 4 hours to remove carbon adsorption on the substrate surface and complete the reconstruction of a smooth and stable step. (Refer to...) Figure 2 As shown, the treated substrate is placed horizontally on a support frame. Sulfur powder, used as a chalcogenide source, is added to the first source support tube, and molybdenum trioxide, used as a transition metal source, is added to the second source support tube. In this embodiment, the transition metal source is a pressed molybdenum trioxide sheet.

[0109] (2) Evacuate the cavity to 0.02 Torr, introduce argon into the first inlet pipe, and introduce a mixture of argon and oxygen into the second inlet pipe. The flow rate ratio of argon to oxygen in the second inlet pipe is 100:6. Adjust the gas pressure in the cavity to 1 Torr.

[0110] (3) Set the preset temperature of the first source support tube to 120℃ and the heating rate to 4℃ / min. Set the preset temperature of the second source support tube to 580℃ and the heating rate to 19℃. Set the preset temperature of the substrate, i.e. the epitaxial growth temperature, to 930℃ and the heating rate to 31℃ / min.

[0111] (4) The epitaxial growth time is set to 50 min. The epitaxial growth proceeds uniformly on the substrate surface through nucleation, growth, and merging, as per the reference. Figure 3 As shown, in this embodiment, an 8-inch monolayer molybdenum sulfide film was prepared by epitaxial growth.

[0112] The 8-inch monolayer molybdenum sulfide film obtained in this embodiment was characterized, referring to... Figure 4 As shown, the molybdenum sulfide film has a smooth surface, without gaps or thick layers. (Refer to...) Figure 5 As shown, the thin film replicates the surface steps of the sapphire substrate, with a thickness of 0.6 nm, confirming it to be a single-layer molybdenum sulfide thin film.

[0113] To verify the spatial uniformity of the monolayer molybdenum sulfide film, Raman and fluorescence measurements were performed on the entire wafer at a resolution of 1 cm. (Refer to...) Figure 6 and Figure 7 As shown, the monolayer molybdenum sulfide film has obvious MoS2 Raman peaks and A exciton peaks, and the Raman and fluorescence spectra at all test points are basically consistent, indicating that the film is spatially uniform across the entire 8-inch wafer.

[0114] To verify the epitaxial properties of the 8-inch MoS2 thin film, XRD tests were performed on the entire wafer in this application. (See reference...) Figure 8As shown, the θ-2θ diffraction pattern of sapphire XRD is displayed. <1120> With MoS2 <1010> The detection of diffraction peaks at the same φ angle indicates that the MoS2 film is epitaxially grown on a sapphire substrate with a 30° rotation angle. Rotating the φ angle reveals six diffraction peaks in the MoS2 film. Figure 9 As shown, this indicates that the grain orientation inside the MoS2 film is ordered.

[0115] Example 2

[0116] This embodiment uses Figure 1 The wafer-level transition metal chalcogenide preparation apparatus shown is used for batch epitaxial growth of 4-inch monolayer molybdenum sulfide films.

[0117] Preparation method of wafer-level transition metal chalcogenides:

[0118] (1) Place sulfur powder and molybdenum trioxide tablets in the first source support pipe and the second source support pipe respectively.

[0119] (2) Place three groups of 4-inch sapphire substrates back to back on the sample hanger, with a spacing of 10cm between groups.

[0120] (3) Evacuate the cavity to 0.02 Torr, introduce argon into the first inlet pipe, and introduce a mixture of argon and oxygen into the second inlet pipe. The flow rate ratio of argon to oxygen in the second inlet pipe is 100:3. Adjust the gas pressure in the cavity to 1.3 Torr.

[0121] (4) Set the preset temperature of the first source support tube to 120℃ and the heating rate to 4℃ / min; set the preset temperature of the second source support tube to 560℃ and the heating rate to 19℃ / min; set the preset temperature of the substrate, i.e. the epitaxial growth temperature, to 880℃ and the heating rate to 31℃ / min.

[0122] (5) The epitaxial growth time was set to 70 min. After uniform nucleation, growth, and merging, six 4-inch monolayer MoS2 films were finally obtained, as shown in the figure. Figure 10 As shown, where Figure 10 The right side is a magnified view of a portion of the left side.

[0123] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0124] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims, and the specification and drawings can be used to interpret the content of the claims.

Claims

1. An apparatus for preparing wafer-level transition metal chalcogenides, characterized in that, include: Reaction chamber; A first source support tube and a second source support tube are disposed inside the reaction chamber. The first source support tube has a first source support surface for supporting a chalcogenide source, and the second source support tube has a second source support surface for supporting a transition metal source. A first air inlet pipe and a second air inlet pipe, both of which penetrate the reaction chamber; the first air inlet pipe is connected to the first source support pipe to provide vertically upward gas to the first source support pipe, and the second air inlet pipe is connected to the second source support pipe to provide vertically upward gas to the second source support pipe; A hollow support frame disposed inside the reaction chamber, the support frame having a support position for supporting the substrate; In the vertical direction, the position of the support is higher than the first source support surface and the second source support surface.

2. The apparatus for preparing wafer-level transition metal chalcogenides according to claim 1, characterized in that, The number of the first source support tubes is multiple, and the multiple first source support tubes are evenly distributed in a ring with equal spacing; and / or, The number of the second source support tubes is multiple, and the multiple second source support tubes are evenly distributed in a ring with equal spacing; and / or, In the vertical direction, the second source support surface is positioned higher than the first source support surface; and / or, The support frame has multiple support positions spaced apart in the vertical direction.

3. The apparatus for preparing wafer-level transition metal chalcogenides according to any one of claims 1 to 2, characterized in that, The number of the second source support tubes is greater than or equal to the number of the first source support tubes; and / or, In the vertical direction, the ratio of the distance between the support position and the second source support surface to the distance between the second source support surface and the first source support surface is (1-3):1; and / or, The apparatus for preparing wafer-level transition metal chalcogenides further includes a temperature control device located around the reaction chamber. The temperature control device is used to control the temperature of the first source support tube, the second source support tube, and the support frame.

4. A method for preparing a wafer-level transition metal chalcogenide compound, characterized in that, The apparatus for preparing wafer-level transition metal chalcogenides according to any one of claims 1 to 3 comprises the following steps: Provide a substrate and place the substrate on the support frame; Evaporate the chalcogenide source located on the first source support surface and the transition metal source located on the second source support surface; Vertically upward gas is supplied through the first and second air inlets to carry the evaporated chalcogenide source and the transition metal source to the substrate, and a transition metal chalcogenide compound is epitaxially grown on the surface of the substrate.

5. The method for preparing wafer-level transition metal chalcogenides according to claim 4, characterized in that, Evaporation of the chalcogenide source located in the first source support tube includes: controlling the temperature of the first source support tube to be between 80°C and 300°C; and / or, Evaporation of the transition metal source located in the second source support tube includes: controlling the temperature of the second source support tube to be 450℃~850℃; and / or, Epitaxial growth of transition metal chalcogenides on the surface of the substrate includes controlling the temperature of the substrate to be 750°C to 1000°C.

6. The method for preparing wafer-level transition metal chalcogenides according to claim 4, characterized in that, The chalcogenide source includes at least one of elemental sulfur, elemental selenium, and elemental tellurium; and / or, The transition metal source includes at least one of the following: molybdenum oxide, molybdenum chloride, molybdenum inorganic salt compound, tungsten oxide, tungsten chloride, tungsten inorganic salt compound, niobium oxide, niobium chloride, niobium inorganic salt compound, rhenium oxide, rhenium chloride, and rhenium inorganic salt compound; and / or, The substrate includes one of a single-crystal sapphire substrate, a single-crystal gold substrate, a single-crystal mica substrate, and a silicon substrate.

7. The method for preparing wafer-level transition metal chalcogenides according to claim 4, characterized in that, Providing vertically upward gas through the first intake pipe and the second intake pipe includes: A first protective gas is introduced through the first intake pipe, and a second protective gas or a mixture of the second protective gas and oxygen is introduced through the second intake pipe.

8. The method for preparing wafer-level transition metal chalcogenides according to claim 7, characterized in that, The first protective gas includes at least one of nitrogen and argon; and / or, The flow rate of the first protective gas is 100 sccm to 500 sccm; and / or, The second protective gas includes at least one of nitrogen and argon; and / or, The flow rate of the second protective gas is 50 sccm to 200 sccm; and / or, The oxygen flow rate is 0 sccm to 30 sccm.

9. The method for preparing wafer-level transition metal chalcogenides according to any one of claims 4 to 8, characterized in that, The gas pressure for the epitaxial growth is 0.1 Torr to 10 Torr; and / or, The epitaxial growth time is 10s to 4200s.

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