Silicon carbide single crystal growth device

Abstract

The invention provides a silicon carbide single crystal growth device which comprises a device body, and an air inlet is formed in one end of the device body; a first crucible, a second crucible and a first deposition structure are sequentially stacked and coaxially arranged in the device body in the air inlet direction, and the opening end, away from the second crucible, of the first crucible and the air inlet are coaxially arranged. The two ends of the first deposition structure are a small-diameter end and a large-diameter end respectively, the small-diameter end is arranged close to the second crucible, and a flow guide partition plate is arranged at the large-diameter end; the rotary lifting structure comprises a rotary lifting rod, the rotary lifting rod is arranged on the coaxial axis of the second crucible and the first deposition structure in a penetrating manner, one end of the rotary lifting rod is externally connected with a driving device, and the other end of the rotary lifting rod is provided with a seed crystal base. The specific structure of the silicon carbide single crystal growth device is limited, so that a reasonable thermal field design and a reasonable gas flow path are provided in the silicon carbide single crystal growth process, a silicon carbide polycrystalline deposition area is standardized, and recycling of the silicon carbide polycrystalline deposition area is facilitated.

Description

Technical Field

[0001] The invention belongs to the technical field of crystal growth and relates to a silicon carbide single crystal growth device. Background Art

[0002] 4H-SiC has the characteristics of wide bandgap, high breakdown electric field, high thermal conductivity and high saturated electron drift velocity, which enables 4H-SiC-based power devices to operate at higher temperatures, higher voltages and higher frequencies, thereby significantly improving power conversion efficiency and reducing energy loss.

[0003] Currently, there are three main methods for growing silicon carbide single crystals: physical vapor transport (PVT), high temperature chemical vapor deposition (HT-CVD) and liquid phase epitaxy (LPE).

[0004] Among them, the PVT method uses the sublimation characteristics of silicon carbide at high temperature, and controls the temperature gradient and pressure gradient to deposit and grow gas phase silicon carbide on the seed crystal. The PVT method has become the mainstream process method in the industry due to its advantages of simple equipment, easy operation and low cost, but its growth rate is slow and defects are difficult to control.

[0005] The HT-CVD method mainly deposits and grows on the seed crystal by mixing carbon source gas and silicon source gas at high temperature. The HT-CVD method has the advantages of fast growth rate, few defects and high purity, but the high consumables cost caused by the characteristics of gas mixing preparation cannot be ignored.

[0006] In the HT-CVD method, in order to increase the growth rate of silicon carbide single crystals, the raw gas flow rate needs to be increased accordingly. However, the temperature gradient and gas flow rate distribution are difficult to control. The raw gas will adhere to the side walls inside the growth chamber to produce polycrystalline silicon carbide in a certain area. Increasing the raw gas flow rate will lead to a decrease in yield while increasing the adhesion of polycrystalline silicon carbide. Among them, the unevenly distributed polycrystalline silicon carbide will affect the gas flow and local thermal field distribution, thereby interfering with the uniformity and consistency of single crystal growth, which may lead to an unstable growth interface and affect the shape and size control of single crystal growth. At the same time, the long-term accumulated polycrystalline layer will cause erosion to the crucible structure, shorten the service life of the crucible and other related equipment components, and increase maintenance and replacement costs.

[0007] After collecting and testing the polycrystalline silicon carbide produced by the HT-CVD method, it was found that its purity was high, meeting the raw material purity requirements for the growth of silicon carbide single crystals by the PVT method. Therefore, while increasing the raw material gas flow rate in the HT-CVD method to ensure the increase in the growth rate of silicon carbide single crystals, how to reduce the impact of polycrystalline silicon carbide adhesion on single crystal growth, and how to reasonably recycle polycrystalline silicon carbide for PVT growth raw materials, have become technical problems that need to be solved urgently. Summary of the invention

[0008] In view of the deficiencies in the prior art, the object of the present invention is to provide a silicon carbide single crystal growth device, and in particular, to provide a silicon carbide single crystal growth device based on the HTCVD method; in the present invention, by limiting the specific structure of the silicon carbide single crystal growth device, a reasonable thermal field design and gas flow path are provided during the growth process of the silicon carbide single crystal, and the silicon carbide polycrystalline deposition area is standardized, which is conducive to its recycling.

[0009] To achieve this object, the present invention adopts the following technical solutions:

[0010] The present invention provides a silicon carbide single crystal growth device, which includes a device body, a first crucible, a second crucible, a first deposition structure and a rotating lifting structure, and an air inlet is provided at one end of the device body;

[0011] The first crucible, the second crucible and the first deposition structure are sequentially stacked and coaxially arranged in the device body along the air inlet direction, the first crucible, the second crucible and the first deposition structure are all hollow structures, the first crucible is coaxially arranged with the air inlet at an open end away from the second crucible, and the inner diameter of the first crucible is smaller than the inner diameter of the second crucible;

[0012] The two ends of the first deposition structure are respectively a small diameter end and a large diameter end, the small diameter end is arranged close to the second crucible, the large diameter end is arranged close to the other end of the device body opposite to the air inlet, and a guide baffle is arranged at the large diameter end;

[0013] The rotating lifting structure includes a rotating lifting rod, which is arranged on an axis coaxial with the second crucible and the first deposition structure, and one end of the rotating lifting rod is externally connected to a driving device, and the other end is provided with a seed crystal base, the seed crystal base extends into the second crucible, and the side of the seed crystal base facing the first crucible is used for bonding the seed crystal.

[0014] In the present invention, by limiting the specific structure of the silicon carbide single crystal growth device, a reasonable thermal field design and gas flow path are provided during the growth of the silicon carbide single crystal, and the silicon carbide polycrystalline deposition area is standardized, which is conducive to its recycling.

[0015] It should be noted that the shape and size of the device body are not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments according to actual conditions. The shape of the device body can be cylindrical, and its size can be enlarged or reduced in proportion to the first crucible, the second crucible, the first deposition structure, the rotating lifting structure and other components.

[0016] It should be noted that the specific position of the air inlet at one end of the device body is not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments according to actual conditions. The air inlet can be designed to be located in the middle of one end of the device body; the diameter of the air inlet can be the same as the hollow diameter of the first crucible, so that the hollow part of the first crucible becomes an air inlet channel, and the air inlet channel can be connected to an external gas supply source.

[0017] It should be noted that the present invention does not specifically limit the size of the first crucible and the second crucible, and those skilled in the art can make adaptive adjustments according to actual conditions. The first crucible and the second crucible are hollow structures, that is, the first crucible and the second crucible are both annular structures; the reason why the inner diameter of the first crucible is smaller than the inner diameter of the second crucible is that this structure is conducive to the growth gas to quickly enter the growth area between the second crucible after high-temperature decomposition, and evenly distribute in the growth area, providing a stable atmosphere for crystal growth.

[0018] It should be noted that the material of the first deposition structure in the present invention is preferably graphite. Due to the different crystal forms of the target silicon carbide raw materials to be collected, the temperature control range near the first deposition structure area is different. For example, the collection temperature of 4H-type silicon carbide raw materials needs to be controlled at 2200°C ~ 2500°C, and the collection temperature of 3C-type silicon carbide raw materials needs to be controlled at 1600°C ~ 1800°C. The graphite surface can be coated with materials such as tantalum carbide or silicon carbide according to different temperature requirements. Silicon carbide ceramics have the same chemical composition and similar thermal expansion coefficient as polycrystalline silicon carbide, excellent adhesion, and good corrosion resistance to ensure the compact deposition of polycrystalline silicon carbide, and are mainly used in the collection of 3C-type silicon carbide raw materials at lower temperatures.

[0019] It should be noted that the inner diameter of the first deposition structure in the present invention gradually increases with the direction of the air inlet, so that the internal gas flow space gradually increases, the gas flow rate slows down accordingly, and the contact time between the gas and the deposition area is increased, which is beneficial to the deposition of polycrystalline silicon carbide.

[0020] It should be noted that the specific structure and form of the driving device are not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments according to actual conditions. The driving device can be a rotating motor.

[0021] As a preferred technical solution of the present invention, a first annular partition is provided at the edge of the small diameter end in a direction away from the inner wall of the device body.

[0022] It should be noted that the material of the first annular partition is not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments according to actual conditions. The center of the first annular partition is on the central axis of the rotating lifting rod, and its outer edge and the inner edge of the small diameter end can be threadedly connected to prevent part of the polycrystalline silicon carbide from falling down to the single crystal growth area and affecting the crystal growth quality.

[0023] Preferably, the inner diameter of the first annular partition plate is smaller than the outer diameter of the seed crystal base.

[0024] It should be noted that the inner diameter of the first annular partition in the present invention is smaller than the outer diameter of the seed crystal base. This is because on the one hand it can prevent the polycrystalline silicon carbide formed by deposition from falling into the crystal growth area below, and on the other hand it can speed up the flow rate of the gas when entering the deposition area. When assembling the device body, the rotating lifting rod loaded with the seed crystal base can be first extended into the second crucible, and then the first annular partition can be fastened.

[0025] Preferably, radial holes are evenly distributed at the connection between the small diameter end and the first annular partition.

[0026] It should be noted that radial holes are distributed at the connection between the small diameter end and the first annular partition in the present invention. This is because the gas flow rate passing through the first annular partition is faster, and the gas outside the growth area will enter the deposition area along the radial holes.

[0027] As a preferred technical solution of the present invention, a second annular partition is arranged at the edge of the large diameter end in a direction close to the inner wall of the device body, and the guide partition is arranged on the second annular partition.

[0028] Preferably, the second annular partition is detachably connected to the guide partition.

[0029] It should be noted that the material of the second annular partition is not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments according to actual conditions. The center of the second annular partition is on the central axis of the rotating lifting rod, and its inner edge can be threadedly connected to the outer edge of the large diameter end.

[0030] It should be noted that the specific manner of the detachable connection between the second annular partition and the guide partition in the present invention is not particularly limited, and those skilled in the art can make adaptive adjustments according to actual conditions. Among them, the detachable connection can be a threaded connection or a clamping connection.

[0031] It should be noted that the outer edge of the guide baffle in the present invention is arranged to exceed the outer edge of the second annular baffle, so as to limit the movement of the guide baffle and the second deposition structure toward the direction where the first crucible is located.

[0032] As a preferred technical solution of the present invention, a first heat-insulating structure is provided on the inner wall of the device body in a circumferential direction along the air inlet direction.

[0033] Preferably, a second heat-insulating structure is provided at one end of the first crucible close to the air inlet.

[0034] Preferably, the second heat-insulating structure is an annular structure, and the cross-sectional area of ​​the annular structure perpendicular to the air inlet direction is the same as the cross-sectional area of ​​the first crucible perpendicular to the air inlet direction.

[0035] It should be noted that the present invention does not specifically limit the material, size and thickness of the first heat-insulating structure and the second heat-insulating structure, and those skilled in the art can make adaptive adjustments according to actual conditions. Among them, an annular first heat-insulating structure can be arranged between the inner side wall surface of the device body and the first crucible and the second crucible, and an annular second heat-insulating structure can be arranged between the inner bottom surface of the device body and the first crucible. The first heat-insulating structure and the second heat-insulating structure can isolate the heat radiation effect of the heating crucible to the outer single crystal growth device, thereby reducing the temperature of the device.

[0036] Preferably, the outer edge of the second annular partition is clamped on the inner wall of the first thermal insulation structure.

[0037] As a preferred technical solution of the present invention, the silicon carbide single crystal growth device also includes a second deposition structure, which is circumferentially arranged on the outer wall of the rotating lifting rod and is arranged inside the first deposition structure.

[0038] It should be noted that the present invention performs a necking treatment on the gas path at the air outlet of the deposition area (that is, when a second deposition structure is provided), so that the speed of the gas exhaust device is accelerated and the corrosion effect of subsequent gas on the inner wall of the quartz tube of the single crystal growth device is reduced; the second deposition structure in the present invention can also be used to protect the rotating lifting rod in the deposition area.

[0039] Preferably, the second deposition structure comprises a portion of equal diameter and a portion of gradually expanding diameter connected in sequence.

[0040] Preferably, there is a certain distance between an end of the uniform diameter portion away from the gradually expanding portion and the small diameter end.

[0041] Preferably, two ends of the gradually expanding portion are a small diameter portion and a large diameter portion respectively, and the small diameter portion is connected to the same diameter portion.

[0042] It should be noted that in the present invention, the gas path at the outlet of the deposition area is necked, that is, the second deposition structure formed by connecting the same diameter portion and the gradually expanding portion in the present invention, and the gradually expanding portion and the large diameter end of the first deposition structure form a necking structure, so that the speed of the gas exhaust device is accelerated and the corrosion effect of the subsequent gas on the inner wall of the quartz tube of the single crystal growth device is reduced.

[0043] As a preferred technical solution of the present invention, the guide baffle is an annular baffle.

[0044] The inner wall of the annular partition is in contact with the outer wall of the rotary lifting rod, the outer edge of the annular partition is detachably connected to the large diameter end, and the outer edge of the annular partition is arranged beyond the outer edge of the large diameter end.

[0045] Preferably, the annular partition has flow guide holes evenly distributed along the circumference of the rotary lifting rod.

[0046] Alternatively, the inner wall of the annular partition is detachably connected to the outer edge of the large diameter portion, the outer edge of the annular partition is detachably connected to the large diameter end, and the outer edge of the annular partition is arranged beyond the outer edge of the large diameter end.

[0047] Preferably, flow guide holes are evenly distributed on the annular partition between the large diameter portion and the large diameter end.

[0048] It should be noted that in the present invention, the guide baffle has guide holes corresponding to the gap between the first deposition structure and the rotating lifting rod (or the second deposition structure). The gas flow rate can be locally increased at the guide holes, so that the gas after deposition quickly leaves the deposition area and is discharged from the single crystal growth device.

[0049] As a preferred technical solution of the present invention, the rotary lifting rod is a hollow structure, and the hollow structure is used to place a temperature detector.

[0050] It should be noted that the specific length and material of the rotary lifting rod are not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments according to actual conditions. The rotary lifting rod is a hollow structure in which a temperature detector can be placed, which is convenient for subsequent temperature detection of the growth area.

[0051] Preferably, the diameter of the seed crystal on the seed crystal base is less than two-thirds of the inner diameter of the second crucible.

[0052] It should be noted that the specific connection method between the rotary lifting rod and the seed crystal base in the present invention is not particularly limited, and those skilled in the art can make adaptive adjustments according to actual conditions. Among them, the rotary lifting rod and the seed crystal base can be detachably connected, specifically, they can be threaded connections; the rotary lifting rod can drive the seed crystal base to operate, thereby driving the seed crystal to rotate so that its single crystal growth is more uniform. The reason why the diameter of the seed crystal on the seed crystal base is limited to less than two-thirds of the inner diameter of the second crucible is that at this ratio, the silicon carbide single crystal can be guaranteed to grow stably inside the second crucible. The seed crystal moves in the vertical direction in the single crystal growth device through the rotary lifting rod. As the length of the single crystal grows, the seed crystal can be gradually lifted within the vertical length range of the second crucible during growth.

[0053] As a preferred technical solution of the present invention, an air outlet is provided on the other end of the device body opposite to the air inlet.

[0054] Alternatively, an air outlet is provided on the inner side wall of the device body between the guide baffle and the device body.

[0055] It should be noted that the specific position, shape, size and number of the air outlet are not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments according to actual conditions. Among them, the air outlet can be designed on the device body corresponding to the guide hole directly above the guide baffle, and the device body at this location can be connected to an external sealing flange, or it can be opened on the side wall of the device body above the guide baffle. The former design directly above the side wall has a shorter gas flow path, which can make the gas quickly leave the growth device after leaving the deposition area, avoiding the deposition of excess silicon carbide polycrystalline on the surface of the quartz tube at the side wall of the device.

[0056] As a preferred technical solution of the present invention, the silicon carbide single crystal growth device also includes a heating device circumferentially arranged on the outer wall of the device body, and the heating device includes a first heating structure, a second heating structure and a third heating structure arranged in sequence along the air inlet direction.

[0057] Preferably, the first heating structure, the second heating structure and the third heating structure are all coil heaters.

[0058] It should be noted that the present invention does not impose any special restrictions on the type, size, number of turns, etc. of the coil used in the heating device, and those skilled in the art can make adaptive adjustments according to actual conditions.

[0059] Preferably, the height of the first heating structure is set corresponding to the height of the first crucible.

[0060] Preferably, the height of the second heating structure is set corresponding to the height of the second crucible.

[0061] Preferably, the height of the third heating structure is set corresponding to the height of the first deposition structure.

[0062] Preferably, the heating temperature of the first heating structure is 2450℃~2550℃, for example, it can be 2450℃, 2460℃, 2470℃, 2480℃, 2490℃, 2500℃, 2510℃, 2520℃, 2530℃, 2540℃, 2550℃, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0063] Preferably, the heating temperature of the second heating structure is 2650℃~2850℃, for example, it can be 2650℃, 2660℃, 2670℃, 2680℃, 2690℃, 2700℃, 2710℃, 2720℃, 2730℃, 2740℃, 2750℃, 2760℃, 2770℃, 2780℃, 2790℃, 2800℃, 2820℃, 2840℃, 2850℃, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0064] Preferably, the heating temperature of the third heating structure is 1800℃~2000℃, for example, it can be 1800℃, 1820℃, 1840℃, 1860℃, 1880℃, 1900℃, 1920℃, 1940℃, 1960℃, 1980℃, 2000℃, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0065] It should be noted that the reason why the present invention limits the first heating structure, the second heating structure and the third heating structure to correspond to the height of the first crucible, the height of the second crucible and the height of the first deposition structure respectively, and limits the heating temperature of each heating structure is because the first heating structure mainly plays a role in decomposing the precursor gas; the second heating structure mainly ensures that the temperature of the crystal growth area is maintained within the set value area; the third heating structure makes the polycrystalline silicon carbide deposited grain size smaller and the quality better within this temperature range, ensuring that the axial temperature gradient inside the single crystal growth device changes uniformly and avoiding large temperature differences.

[0066] As a preferred technical solution of the present invention, the first crucible, the second crucible, the first deposition structure and the second deposition structure are all made of the same material.

[0067] Preferably, the first crucible is made of graphite.

[0068] Compared with the prior art, the present invention has the following beneficial effects:

[0069] The present invention defines the specific structure of the silicon carbide single crystal growth device, so that the silicon carbide single crystal growth process has a reasonable thermal field design and gas flow path, and standardizes the silicon carbide polycrystalline deposition area, which is conducive to its recycling.

[0070] The present invention arranges a deposition area above the second crucible to increase the flow rate of the raw material gas while depositing and collecting the polycrystalline silicon carbide formed above the growth area, thereby ensuring a faster single crystal growth rate and converting the excessive raw material gas into polycrystalline silicon carbide for use in the preparation of PVT method crystal growth raw materials, thereby avoiding the problem of the HT-CVD method simply increasing the single crystal growth rate and resulting in a low yield.

[0071] The present invention adds radial holes at the air inlet of the deposition area, which can reintroduce the gas outside the growth area into the deposition area for deposition, increase the contact between the gas and the deposition area, and increase the deposition amount of polycrystalline silicon carbide to a certain extent. It provides a guiding path for the gas in the single crystal growth device and reduces the occurrence of turbulence and convection. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1 A schematic structural diagram of a silicon carbide single crystal growth device provided in Example 1 of the present invention;

[0073] Figure 2 A schematic diagram of the structure of a silicon carbide single crystal growth device provided in Example 2 of the present invention;

[0074] Figure 3 A schematic diagram of the structure of a silicon carbide single crystal growth device provided in Example 3 of the present invention;

[0075] Figure 4 A schematic diagram of the structure of a silicon carbide single crystal growth device provided in Example 4 of the present invention;

[0076] Among them, 1-device body; 2-first crucible; 3-second crucible; 4-first deposition structure; 5-driving device; 6-air inlet; 7-air outlet; 8-seed crystal base; 9-rotating lifting rod; 10-first annular partition; 11-second annular partition; 12-guide partition; 13-second thermal insulation structure; 14-first thermal insulation structure; 15-guide hole; 16-second deposition structure; 17-radial hole. DETAILED DESCRIPTION

[0077] It should be understood that, in the description of the present invention, the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0078] It should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "disposed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0079] Those skilled in the art should understand that the present invention necessarily includes necessary pipelines, conventional valves and general pump equipment for realizing a complete process, but the above content does not belong to the main inventive point of the present invention. Those skilled in the art can add layouts on their own based on the process flow and equipment structure selection, and the present invention does not make special requirements and specific limitations on this.

[0080] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0081] The present invention provides a silicon carbide single crystal growth device, which includes a device body 1, a first crucible 2, a second crucible 3, a first deposition structure 4 and a rotating lifting structure, and an air inlet 6 is provided at one end of the device body 1;

[0082] A first crucible 2, a second crucible 3 and a first deposition structure 4 are sequentially stacked and coaxially arranged in the device body 1 along the air inlet direction. The first crucible 2, the second crucible 3 and the first deposition structure 4 are all hollow structures. The opening end of the first crucible 2 away from the second crucible 3 is coaxially arranged with the air inlet 6, and the inner diameter of the first crucible 2 is smaller than the inner diameter of the second crucible 3.

[0083] The first deposition structure 4 has two ends, a small diameter end and a large diameter end, respectively. The small diameter end is arranged close to the second crucible 3, and the large diameter end is arranged close to the other end of the device body 1 opposite to the air inlet 6, and a guide baffle 12 is arranged at the large diameter end.

[0084] The rotating lifting structure includes a rotating lifting rod 9, which is arranged on a coaxial axis between the second crucible 3 and the first deposition structure 4, and one end of the rotating lifting rod 9 is externally connected to a driving device 5, and the other end is provided with a seed crystal base 8, the seed crystal base 8 extends into the second crucible 3, and the seed crystal base 8 faces the side of the first crucible 2 for bonding the seed crystal.

[0085] It should be noted that the shape and size of the device body 1 are not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments according to actual conditions. The shape of the device body 1 can be cylindrical, and its size can be enlarged or reduced in proportion to the first crucible 2, the second crucible 3, the first deposition structure 4, the rotating lifting structure and other components.

[0086] It should be noted that the specific position of the air inlet 6 at one end of the device body 1 is not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments according to actual conditions. The air inlet 6 can be designed to be located in the middle of one end of the device body 1; the diameter of the air inlet 6 can be the same as the hollow diameter of the first crucible 2, so that the hollow part of the first crucible 2 becomes an air inlet channel, and the air inlet channel can be connected to an external gas supply source.

[0087] It should be noted that the present invention does not specifically limit the size of the first crucible 2 and the second crucible 3, and those skilled in the art can make adaptive adjustments according to actual conditions. The first crucible 2 and the second crucible 3 are hollow structures, that is, the first crucible 2 and the second crucible 3 are both annular structures.

[0088] It should be noted that the material of the first deposition structure 4 in the present invention is graphite. Due to the different crystal forms of the target silicon carbide raw materials to be collected, the temperature control range near the area of ​​the first deposition structure 4 is different. For example, the collection temperature of 4H-type silicon carbide raw materials needs to be controlled at 2200°C ~ 2500°C, and the collection temperature of 3C-type silicon carbide raw materials needs to be controlled at 1600°C ~ 1800°C. The graphite surface can be coated with materials such as tantalum carbide or silicon carbide according to different temperature requirements. Silicon carbide ceramics have the same chemical composition and similar thermal expansion coefficient as polycrystalline silicon carbide, excellent adhesion, and good corrosion resistance to ensure the compact deposition of polycrystalline silicon carbide, and are mainly used in the collection of 3C-type silicon carbide raw materials at lower temperatures.

[0089] It should be noted that the inner diameter of the first deposition structure 4 in the present invention gradually increases with the direction of the air inlet, so that the internal gas flow space gradually increases, the gas flow rate slows down accordingly, and the contact time between the gas and the deposition area is increased, which is beneficial to the deposition of polycrystalline silicon carbide.

[0090] It should be noted that the specific structure and form of the driving device 5 are not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments according to actual conditions. The driving device 5 can be a rotating motor.

[0091] In one embodiment, a first annular partition plate 10 is disposed at the edge of the small diameter end in a direction away from the inner wall of the device body 1 .

[0092] It should be noted that the material of the first annular partition 10 is not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments according to actual conditions. The center of the first annular partition 10 is on the central axis of the rotating lifting rod 9, and its outer edge and the inner edge of the small diameter end can be threadedly connected to prevent part of the polycrystalline silicon carbide from falling down to the single crystal growth area and affecting the crystal growth quality.

[0093] In one embodiment, the inner diameter of the first annular partition plate 10 is smaller than the outer diameter of the seed crystal base 8 .

[0094] It should be noted that the inner diameter of the first annular partition 10 in the present invention is smaller than the outer diameter of the seed crystal base 8. When the device body 1 is assembled, the rotating lifting rod 9 loaded with the seed crystal base 8 can be first extended into the second crucible 3, and then the first annular partition 10 is buckled.

[0095] In one embodiment, radial holes 17 are evenly distributed at the connection between the small diameter end and the first annular partition plate 10 .

[0096] It should be noted that radial holes 17 are evenly distributed at the connection between the small diameter end and the first annular baffle 10 in the present invention. This is because the air flow velocity passing through the first annular baffle 10 is relatively fast, and the gas outside the growth area will enter the deposition area along the radial holes 17.

[0097] In one embodiment, a second annular partition plate 11 is disposed at the edge of the large diameter end in a direction close to the inner wall of the device body 1 , and a flow guide partition plate 12 is disposed on the second annular partition plate 11 .

[0098] In one embodiment, the second annular partition 11 is detachably connected to the guide partition 12 .

[0099] It should be noted that the material of the second annular partition 11 is not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments according to actual conditions. The center of the second annular partition 11 is on the central axis of the rotating lifting rod 9, and its inner edge can be threadedly connected to the outer edge of the large diameter end.

[0100] It should be noted that the specific manner of the detachable connection between the second annular partition 11 and the guide partition 12 in the present invention is not particularly limited, and those skilled in the art can make adaptive adjustments according to actual conditions. Among them, the detachable connection can be a threaded connection or a clamping connection.

[0101] It should be noted that the outer edge of the guide baffle 12 in the present invention is arranged to exceed the outer edge of the second annular baffle 11 to limit the movement of the guide baffle 12 and the second deposition structure 16 toward the direction of the first crucible 2.

[0102] In one embodiment, a first heat-insulating structure 14 is circumferentially provided on the inner wall of the device body 1 along the air inlet direction.

[0103] In one embodiment, a second heat-insulating structure 13 is disposed at one end of the first crucible 2 close to the air inlet 6 .

[0104] In one embodiment, the second heat-insulating structure 13 is an annular structure, and the cross-sectional area of ​​the annular structure perpendicular to the air inlet direction is the same as the cross-sectional area of ​​the first crucible 2 perpendicular to the air inlet direction.

[0105] It should be noted that the material, size and thickness of the first heat-insulating structure 14 and the second heat-insulating structure 13 are not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments according to actual conditions. Among them, an annular first heat-insulating structure 14 can be arranged between the inner side wall surface of the device body 1 and the first crucible 2 and the second crucible 3, and an annular second heat-insulating structure 13 can be arranged between the inner bottom surface of the device body 1 and the first crucible 2. The first heat-insulating structure 14 and the second heat-insulating structure 13 can isolate the heat radiation effect of the heating crucible to the outer single crystal growth device, thereby reducing the temperature of the device.

[0106] In one embodiment, the outer edge of the second annular partition 11 is snap-fitted onto the inner wall of the first heat-insulating structure 14 .

[0107] In one embodiment, the silicon carbide single crystal growth apparatus further includes a second deposition structure 16 , which is circumferentially disposed on the outer wall of the rotary lifting rod 9 and disposed within the first deposition structure 4 .

[0108] It should be noted that the present invention performs a necking treatment on the gas path at the air outlet of the deposition area (that is, when a second deposition structure 16 is provided), so that the speed of the gas exhaust device is accelerated and the corrosion effect of subsequent gas on the inner wall of the quartz tube of the single crystal growth device is reduced; the second deposition structure 16 in the present invention can also be used to protect the rotating lifting rod 9 in the deposition area.

[0109] In one embodiment, the second deposition structure 16 includes a uniform diameter portion and a gradually diverging portion connected in sequence.

[0110] In one embodiment, there is a certain distance between an end of the uniform diameter portion away from the gradually expanding portion and the small diameter end.

[0111] It should be noted that in the present invention, there is a certain distance between the end of the same diameter portion away from the gradually expanding portion and the small diameter end. The certain distance means that the end of the same diameter portion away from the gradually expanding portion is non-contacting with the small diameter end, and the gradually expanding portion is also non-contacting with the inner top wall of the device body 1 as much as possible, so that the gas can be discharged faster.

[0112] In one embodiment, two ends of the gradually expanding portion are a small diameter portion and a large diameter portion, respectively, and the small diameter portion is connected to the same diameter portion.

[0113] It should be noted that in the present invention, the gas path at the outlet of the deposition area is necked, that is, the second deposition structure 16 formed by connecting the same diameter portion and the gradually expanding portion in the present invention, the gradually expanding portion and the large diameter end of the first deposition structure 4 form a necking structure, so that the speed of the gas exhaust device is accelerated, and the corrosion effect of the subsequent gas on the inner wall of the quartz tube of the single crystal growth device is reduced.

[0114] In one embodiment, the guide baffle 12 is an annular baffle.

[0115] In one embodiment, the inner wall of the annular partition contacts and is connected to the outer wall of the rotating lifting rod 9, the outer edge of the annular partition is detachably connected to the large diameter end, and the outer edge of the annular partition is set beyond the outer edge of the large diameter end, and the annular partition has guide holes 15 evenly distributed along the circumference of the rotating lifting rod 9.

[0116] In one embodiment, the inner wall of the annular partition is detachably connected to the outer edge of the large diameter portion, the outer edge of the annular partition is detachably connected to the large diameter end, and the outer edge of the annular partition is set beyond the outer edge of the large diameter end, and the guide holes 15 are evenly distributed on the annular partition between the large diameter portion and the large diameter end.

[0117] It should be noted that in the present invention, the guide baffle 12 has a guide hole 15 corresponding to the gap between the first deposition structure 4 and the rotating lifting rod 9 (or the second deposition structure 16). The gas flow rate can be locally increased at the guide hole 15, so that the gas after deposition can quickly leave the deposition area and be discharged from the single crystal growth device.

[0118] In one embodiment, the rotary lifting rod 9 is a hollow structure, and the hollow structure is used to place the temperature detector.

[0119] It should be noted that the present invention does not specifically limit the specific length and material of the rotary lifting rod 9, and those skilled in the art can make adaptive adjustments according to actual conditions. The rotary lifting rod 9 is a hollow structure in which a temperature detector can be placed, which is convenient for subsequent temperature detection work in the growth area.

[0120] In one embodiment, the diameter of the seed crystal on the seed crystal base 8 is less than two-thirds of the inner diameter of the second crucible 3 .

[0121] It should be noted that the specific connection method between the rotary lifting rod 9 and the seed crystal base 8 in the present invention is not particularly limited, and those skilled in the art can make adaptive adjustments according to actual conditions. Among them, the rotary lifting rod 9 and the seed crystal base 8 can be detachably connected, specifically, they can be threaded; the rotary lifting rod 9 can drive the seed crystal base 8 to operate, and then drive the seed crystal to rotate to make its single crystal growth more uniform. The reason why the diameter of the seed crystal on the seed crystal base 8 is limited to less than two-thirds of the inner diameter of the second crucible 3 is that at this ratio, the silicon carbide single crystal can be guaranteed to grow stably inside the second crucible 3. The seed crystal moves in the vertical direction in the single crystal growth device through the rotary lifting rod 9. As the length of the single crystal grows, the seed crystal is gradually lifted within the vertical length range of the second crucible 3 during growth.

[0122] In one embodiment, an air outlet 7 is provided on the other end of the device body 1 opposite to the air inlet 6 .

[0123] In one embodiment, an air outlet 7 is provided on the inner wall of the device body 1 between the guide baffle 12 and the device body 1 .

[0124] It should be noted that the specific position, shape, size and number of the air outlet 7 are not particularly limited in the present invention, and those skilled in the art can make adaptive adjustments according to actual conditions. Among them, the air outlet 7 can be designed on the device body 1 corresponding to the air guide hole 15 opened on the guide baffle 12, and the device body 1 at this location can be connected to an external sealing flange, or it can be opened on the side wall of the device body 1 above the guide baffle 12.

[0125] In one embodiment, the silicon carbide single crystal growth device further includes a heating device circumferentially arranged on the outer wall of the device body 1, and the heating device includes a first heating structure, a second heating structure and a third heating structure sequentially arranged along the air inlet direction.

[0126] In one embodiment, the first heating structure, the second heating structure and the third heating structure are coil heaters.

[0127] It should be noted that the present invention does not impose any special restrictions on the type, size, number of turns, etc. of the coil used in the heating device, and those skilled in the art can make adaptive adjustments according to actual conditions.

[0128] In one embodiment, the height of the first heating structure is set to correspond to the height of the first crucible 2 .

[0129] In one embodiment, the height of the second heating structure is set to correspond to the height of the second crucible 3 .

[0130] In one embodiment, the height of the third heating structure is set to correspond to the height of the first deposition structure 4 .

[0131] In one embodiment, the heating temperature of the first heating structure is 2450°C to 2550°C, for example, it can be 2450°C, 2460°C, 2470°C, 2480°C, 2490°C, 2500°C, 2510°C, 2520°C, 2530°C, 2540°C, 2550°C, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0132] In one embodiment, the heating temperature of the second heating structure is 2650℃~2850℃, for example, it can be 2650℃, 2660℃, 2670℃, 2680℃, 2690℃, 2700℃, 2710℃, 2720℃, 2730℃, 2740℃, 2750℃, 2760℃, 2770℃, 2780℃, 2790℃, 2800℃, 2820℃, 2840℃, 2850℃, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0133] In one embodiment, the heating temperature of the third heating structure is 1800°C to 2000°C, for example, it can be 1800°C, 1820°C, 1840°C, 1860°C, 1880°C, 1900°C, 1920°C, 1940°C, 1960°C, 1980°C, 2000°C, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0134] It should be noted that the reason why the present invention limits the first heating structure, the second heating structure and the third heating structure to correspond to the height of the first crucible 2, the height of the second crucible 3 and the height of the first deposition structure 4 respectively, and limits the heating temperature of each heating structure is because the first heating structure mainly plays a role in decomposing the precursor gas; the second heating structure mainly ensures that the temperature of the crystal growth area is maintained in the set value area; the third heating structure makes the polycrystalline silicon carbide deposited grain size smaller and the quality better within this temperature range, ensuring that the axial temperature gradient inside the single crystal growth device changes uniformly and avoids large temperature differences.

[0135] In one embodiment, the first crucible 2 , the second crucible 3 , the first deposition structure 4 and the second deposition structure 16 are made of the same material.

[0136] In one embodiment, the first crucible 2 is made of graphite.

[0137] Example 1

[0138] This embodiment provides a silicon carbide single crystal growth device, such as Figure 1 As shown, where:

[0139] The device includes a device body 1, a first crucible 2, a second crucible 3, a first deposition structure 4 and a rotating lifting structure. An air inlet 6 is arranged at one end of the device body 1, and an air outlet 7 is arranged at the other end of the device body 1 opposite to the air inlet 6.

[0140] A first crucible 2, a second crucible 3 and a first deposition structure 4 are stacked in sequence and coaxially arranged in the device body 1 along the air inlet direction. The first crucible 2, the second crucible 3 and the first deposition structure 4 are all hollow structures. The open end of the first crucible 2 away from the second crucible 3 is coaxially arranged with the air inlet 6, and the inner diameter of the first crucible 2 is smaller than the inner diameter of the second crucible 3; the two ends of the first deposition structure 4 are respectively a small diameter end and a large diameter end, the small diameter end is arranged close to the second crucible 3, and the large diameter end is arranged close to the other end of the device body 1 opposite to the air inlet 6, and a guide baffle 12 is arranged at the large diameter end; the rotating lifting structure includes a rotating lifting rod 9, the rotating lifting rod 9 is arranged on an axis coaxial with the second crucible 3 and the first deposition structure 4, and one end of the rotating lifting rod 9 is externally connected to a driving device 5, and the other end is provided with a seed crystal base 8, the seed crystal base 8 extends into the second crucible 3, and the seed crystal base 8 faces the side of the first crucible 2 for bonding the seed crystal.

[0141] A first annular baffle 10 is arranged at the edge of the small diameter end in a direction away from the inner wall of the device body 1. The inner diameter of the first annular baffle 10 is smaller than the outer diameter of the seed crystal base 8. Radial holes 17 are evenly distributed at the connection between the small diameter end and the first annular baffle 10. A second annular baffle 11 is arranged at the edge of the large diameter end in a direction close to the inner wall of the device body 1. A guide baffle 12 is arranged on the second annular baffle 11. The second annular baffle 11 is detachably connected to the guide baffle 12.

[0142] The inner wall of the device body 1 is circumferentially provided with a first insulation structure 14 along the air inlet direction, and a second insulation structure 13 is provided at one end of the first crucible 2 close to the air inlet 6. The second insulation structure 13 is an annular structure, and the cross-sectional area of ​​the annular structure perpendicular to the air inlet direction is the same as the cross-sectional area of ​​the first crucible 2 perpendicular to the air inlet direction. The outer edge of the second annular partition 11 is clamped on the inner wall of the first insulation structure 14.

[0143] The guide baffle 12 is an annular baffle, the inner wall of the annular baffle is in contact with the outer wall of the rotating lifting rod 9, the outer edge of the annular baffle is detachably connected to the large diameter end, and the outer edge of the annular baffle is set beyond the outer edge of the large diameter end, and the annular baffle is evenly distributed with guide holes 15 along the circumference of the rotating lifting rod 9.

[0144] The rotary lifting rod 9 is a hollow structure, and the hollow structure is used to place a temperature detector. The diameter of the seed crystal on the seed crystal base 8 is less than two-thirds of the inner diameter of the second crucible 3 .

[0145] The silicon carbide single crystal growth device also includes a heating device circumferentially arranged on the outer wall of the device body 1, and the heating device includes a first heating structure, a second heating structure and a third heating structure arranged in sequence along the air inlet direction, and the first heating structure, the second heating structure and the third heating structure are all coil heaters. The height of the first heating structure corresponds to the height setting of the first crucible 2, the height of the second heating structure corresponds to the height setting of the second crucible 3, and the height of the third heating structure corresponds to the height setting of the first deposition structure 4. The heating temperature of the first heating structure is 2500°C, the heating temperature of the second heating structure is 2700°C, and the heating temperature of the third heating structure is 1900°C.

[0146] The first crucible 2 , the second crucible 3 , the first deposition structure 4 and the second deposition structure 16 are all made of graphite.

[0147] Example 2

[0148] This embodiment provides a silicon carbide single crystal growth device, such as Figure 2 As shown, the difference from Example 1 is that:

[0149] The silicon carbide single crystal growth device also includes a second deposition structure 16, which is circumferentially arranged on the outer wall of the rotating lifting rod 9 and is arranged in the first deposition structure 4; the second deposition structure 16 includes a same-diameter portion and a gradually expanding portion connected in sequence, and there is a certain distance between the end of the same-diameter portion away from the gradually expanding portion and the small-diameter end, and the two ends of the gradually expanding portion are the small-diameter portion and the large-diameter portion respectively, and the small-diameter portion is connected to the same-diameter portion.

[0150] The inner wall of the annular partition is detachably connected to the outer edge of the large diameter portion, the outer edge of the annular partition is detachably connected to the large diameter end, and the outer edge of the annular partition is arranged beyond the outer edge of the large diameter end, and the annular partition between the large diameter portion and the large diameter end is evenly distributed with guide holes 15.

[0151] The other structures and parameter designs are the same as those in Example 1.

[0152] Compared with Example 1 and Example 2, when there is no second deposition structure 16, part of the silicon carbide polycrystalline will be deposited on the side wall of the rotating lifting rod 9, which is difficult to recover completely. In addition, in the absence of the guiding effect of the second deposition structure 16, the gas may flow back at the upper end of the deposition area, affecting the overall flow path of the gas and further affecting the deposition quality of polycrystalline silicon carbide.

[0153] Example 3

[0154] This embodiment provides a silicon carbide single crystal growth device, such as Figure 3 As shown, the difference from Example 1 is that:

[0155] An air outlet 7 is provided on the inner wall of the device body 1 between the guide baffle 12 and the device body 1 .

[0156] The other structures and parameter designs are the same as those in Example 1.

[0157] Compared with Example 1 and Example 3, the effect of designing the air outlet 7 at one end of the device body 1 is better than designing the air outlet 7 on the side wall. This is because the gas flow path in the former design is shorter, and the guide holes 15 are arranged vertically corresponding to the air outlet 7, which can enable the gas to quickly leave the growth device after leaving the deposition area, thereby avoiding the deposition of excess silicon carbide polycrystals on the surface of the quartz tube at the side wall of the device.

[0158] Example 4

[0159] This embodiment provides a silicon carbide single crystal growth device, such as Figure 4 As shown, the difference from Example 2 is that:

[0160] An air outlet 7 is provided on the inner wall of the device body 1 between the guide baffle 12 and the device body 1 .

[0161] The other structures and parameter designs are the same as those in Example 2.

[0162] In summary, the present invention defines the specific structure of the silicon carbide single crystal growth device, so that the silicon carbide single crystal growth process has a reasonable thermal field design and gas flow path, and standardizes the silicon carbide polycrystalline deposition area, which is conducive to its recycling.

[0163] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention are within the protection scope and disclosure scope of the present invention.

Claims

1. A silicon carbide single crystal growth device, characterized in that: The silicon carbide single crystal growth device comprises a device body, a first crucible, a second crucible, a first deposition structure and a rotating lifting structure, and an air inlet is provided at one end of the device body; The first crucible, the second crucible and the first deposition structure are sequentially stacked and coaxially arranged in the device body along the air inlet direction, the first crucible, the second crucible and the first deposition structure are all hollow structures, the first crucible is coaxially arranged with the air inlet at an open end away from the second crucible, and the inner diameter of the first crucible is smaller than the inner diameter of the second crucible; The two ends of the first deposition structure are respectively a small diameter end and a large diameter end, the small diameter end is arranged close to the second crucible, the large diameter end is arranged close to the other end of the device body opposite to the air inlet, and a guide baffle is arranged at the large diameter end; The rotating lifting structure includes a rotating lifting rod, which is arranged on an axis coaxial with the second crucible and the first deposition structure, and one end of the rotating lifting rod is externally connected to a driving device, and the other end is provided with a seed crystal base, the seed crystal base extends into the second crucible, and the side of the seed crystal base facing the first crucible is used for bonding the seed crystal.

2. The silicon carbide single crystal growth device according to claim 1, characterized in that: A first annular partition is provided at the edge of the small diameter end in a direction away from the inner wall of the device body; Preferably, the inner diameter of the first annular partition is smaller than the outer diameter of the seed crystal base; Preferably, radial holes are evenly distributed at the connection between the small diameter end and the first annular partition.

3. The silicon carbide single crystal growth device according to claim 1 or 2, characterized in that: A second annular baffle is provided at the edge of the large diameter end in a direction close to the inner wall of the device body, and the guide baffle is provided on the second annular baffle; Preferably, the second annular partition is detachably connected to the guide partition.

4. The silicon carbide single crystal growth device according to claim 3, characterized in that: The inner wall of the device body is provided with a first heat-insulating structure in the circumferential direction along the air inlet direction; Preferably, a second heat-insulating structure is provided at one end of the first crucible close to the air inlet; Preferably, the second heat-insulating structure is an annular structure, and the cross-sectional area of ​​the annular structure perpendicular to the air inlet direction is the same as the cross-sectional area of ​​the first crucible perpendicular to the air inlet direction; Preferably, the outer edge of the second annular partition is clamped on the inner wall of the first thermal insulation structure.

5. The silicon carbide single crystal growth device according to any one of claims 1 to 4, characterized in that: The silicon carbide single crystal growth device further includes a second deposition structure, which is circumferentially disposed on the outer wall of the rotary lifting rod and is disposed within the first deposition structure; Preferably, the second deposition structure comprises a portion of equal diameter and a portion of gradually expanding diameter connected in sequence; Preferably, there is a certain distance between the end of the same diameter portion away from the gradually expanding portion and the small diameter end; Preferably, two ends of the gradually expanding portion are a small diameter portion and a large diameter portion respectively, and the small diameter portion is connected to the same diameter portion.

6. The silicon carbide single crystal growth device according to claim 5, characterized in that: The guide baffle is an annular baffle; The inner wall of the annular partition is in contact with the outer wall of the rotary lifting rod, the outer edge of the annular partition is detachably connected to the large diameter end, and the outer edge of the annular partition is arranged beyond the outer edge of the large diameter end; Preferably, the annular partition has flow guide holes evenly distributed along the circumference of the rotary lifting rod; Alternatively, the inner wall of the annular partition is detachably connected to the outer edge of the large diameter portion, the outer edge of the annular partition is detachably connected to the large diameter end, and the outer edge of the annular partition is arranged beyond the outer edge of the large diameter end; Preferably, flow guide holes are evenly distributed on the annular partition between the large diameter portion and the large diameter end.

7. The silicon carbide single crystal growth device according to any one of claims 1 to 6, characterized in that: The rotary lifting rod is a hollow structure, and the hollow structure is used to place a temperature detector; Preferably, the diameter of the seed crystal on the seed crystal base is less than two-thirds of the inner diameter of the second crucible.

8. The silicon carbide single crystal growth device according to any one of claims 1 to 7, characterized in that: An air outlet is provided on the other end of the device body opposite to the air inlet; Alternatively, an air outlet is provided on the inner side wall of the device body between the guide baffle and the device body.

9. The silicon carbide single crystal growth device according to any one of claims 1 to 8, characterized in that: The silicon carbide single crystal growth device further comprises a heating device circumferentially arranged on the outer wall of the device body, wherein the heating device comprises a first heating structure, a second heating structure and a third heating structure sequentially arranged along the air inlet direction; Preferably, the first heating structure, the second heating structure and the third heating structure are all coil heaters; Preferably, the height of the first heating structure is set corresponding to the height of the first crucible; Preferably, the height of the second heating structure is set corresponding to the height of the second crucible; Preferably, the height of the third heating structure is set corresponding to the height of the first deposition structure; Preferably, the heating temperature of the first heating structure is 2450°C to 2550°C; Preferably, the heating temperature of the second heating structure is 2650°C to 2850°C; Preferably, the heating temperature of the third heating structure is 1800°C to 2000°C.

10. The silicon carbide single crystal growth device according to any one of claims 1 to 9, characterized in that: The first crucible, the second crucible, the first deposition structure and the second deposition structure are made of the same material; Preferably, the first crucible is made of graphite.

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