Device and method for recycling raw materials of silicon carbide grown by liquid phase method

Abstract

The invention relates to a device and method for recycling raw materials for growing silicon carbide by a liquid phase method, the device comprising a first growth crucible, a second growth crucible, a transmission device, a blocking block and an external graphite cylinder; the first growth crucible is filled with growth raw materials, and the second growth crucible is located below the first growth crucible as a growth raw material recycling crucible; the top of the transmission device is connected to the blocking block, which is used to drive the blocking block to move up and down, and the blocking block is used to block the through hole at the bottom of the growth crucible; a slot is provided on the outer wall of the bottom of the first growth crucible, and clamps matching the slot are provided on both sides of the top of the transmission device, and the transmission device is also used to control the opening and closing of the clamps, and when the clamps are opened and clamped in the slots, the transmission device drives the first growth crucible to rotate; the invention can realize the recycling and reuse function of raw materials grown by the liquid phase method, significantly reduce the production cost of growing silicon carbide by the liquid phase method, and solve the problem that the crucible cannot rotate due to the recovery of growth raw materials.

Description

Technical Field

[0001] The invention belongs to the technical field of silicon carbide production, and in particular relates to a device and method for recycling raw materials of silicon carbide grown by a liquid phase method. Background Art

[0002] Silicon carbide (SiC) is one of the most important third-generation semiconductor materials. Its unique large bandgap width and high critical breakdown field strength make it an ideal material for manufacturing high-frequency, high-power, radiation-resistant and light-resistant integrated devices. It has been widely used in many fields such as new energy vehicles, 5G communications, and aerospace. The price of silicon carbide substrate wafers in the market is currently high, mainly because the production cost of silicon carbide single crystals is high and the output is low, resulting in a situation of supply exceeding demand in the market.

[0003] In the growth of SiC single crystals by the liquid phase method, the amount of growth raw materials used is relatively small, but they cannot be recycled after each use. Conventionally, the used growth raw materials will be discarded as solid waste along with the growth crucible, resulting in a waste of resources. Imagine if the growth raw materials of SiC single crystals grown by the liquid phase method can be recycled and utilized, this will greatly reduce production costs.

[0004] Therefore, it is very necessary to provide a device and method for recycling and reusing raw materials grown by liquid phase method for silicon carbide. Summary of the invention

[0005] In order to solve one or more technical problems existing in the prior art, the present invention provides a device and method for recycling raw materials for growing silicon carbide by a liquid phase method. The present invention can recycle the growth raw materials of silicon carbide grown by a liquid phase method, realize the recycling of the growth raw materials, greatly reduce the production cost, and ensure the growth quality of the recycled growth raw materials; in addition, it also solves the problem that the crucible cannot rotate due to the recycling of the growth raw materials.

[0006] In a first aspect, the present invention provides a device for recycling and reusing raw materials of silicon carbide grown by a liquid phase method, the device comprising a first growth crucible, a second growth crucible, a transmission device, a blocking block and an external graphite cylinder; a through hole is provided at the bottom of the first growth crucible, a graphite cylinder is arranged around the through hole, and the graphite cylinder is located inside the first growth crucible; two grooves are provided on the outer wall of the bottom of the first growth crucible, the distance between the two grooves is greater than the outer diameter of the external graphite cylinder, and the grooves do not penetrate the bottom of the first growth crucible; the top of the transmission device is connected to the blocking block, and the transmission device is used to drive the blocking block to move up and down, The blocking block is used to block the through hole; clamps cooperating with the slots are also provided on both sides of the top of the transmission device, and the transmission device is also used to control the opening and closing of the clamps. When the clamps are opened and engaged in the slots, the transmission device drives the first growth crucible to rotate, and when the clamps are closed, the clamps are separated from the slots; the first growth crucible is filled with growth raw materials, and the second growth crucible is located below the first growth crucible as a crucible for recycling growth raw materials, and the second growth crucible has the same shape and structure as the first growth crucible; the external graphite cylinder is detachably connected above the graphite cylinder of the second growth crucible.

[0007] Preferably, the transmission device drives the sealing block to move downward to remove the sealing block from the through hole of the first growth crucible, so that the growth raw material in the first growth crucible flows into the second growth crucible. After the growth raw material flows into the second growth crucible, the transmission device continues to drive the sealing block to move downward to the through hole of the second growth crucible.

[0008] Preferably, the wall thickness of the first growth crucible and the second growth crucible are both 3 to 5 mm; the inner diameter of the graphite cylinder is 10 to 20 mm, the height of the graphite cylinder is 10 to 20 mm; and / or the distance between the upper edge of the external graphite cylinder and the bottom of the first growth crucible is 5 to 10 mm.

[0009] Preferably, the diameter of the through hole is 10-20 mm; and / or the width of the blocking block is 10-20 mm, and the thickness of the blocking block is 10-30 mm.

[0010] Preferably, the transmission device drives the blocking block to move up and down over a stroke of 50 to 80 mm.

[0011] Preferably, the material of the first growth crucible and the second growth crucible are both graphite; the material of the blocking block is graphite or silicon carbide; and / or the growth raw material contains Si and a dissolution-aid raw material X, and the dissolution-aid raw material X is one or more of Al, B, Ti, Cr, Fe, Y, Yb, Pr, La, Cu, Ce, Sn, Ge, and Co.

[0012] Preferably, the device further comprises an outer shell crucible, which is sleeved on the outer side of the first growth crucible; the lower end of the outer shell crucible has a hole, and the second growth crucible overlaps the outer periphery of the hole.

[0013] Preferably, the hole is a truncated cone hole or a rectangular hole; the upper edge diameter of the truncated cone hole is 30-60 mm, the lower edge diameter of the truncated cone hole is 50-130 mm, and the lower edge diameter of the truncated cone hole is larger than the upper edge diameter.

[0014] Preferably, the device further comprises N spare growth crucibles, N≥1; the N spare growth crucibles have the same shape and structure as the first growth crucible; the N spare growth crucibles are successively used as growth raw material recovery and reuse crucibles.

[0015] In a second aspect, the present invention provides a method for recycling raw materials for growing silicon carbide by a liquid phase method, the method being carried out using the device for recycling raw materials for growing silicon carbide by a liquid phase method as described in the first aspect of the present invention, and the method comprising the following steps:

[0016] (1) weighing the first growth crucible, the second growth crucible and the growth raw material to be M1, M1 and M2 respectively; the growth raw material comprises Si and a solubilizing raw material X, and the mass ratio of Si contained in the growth raw material, the solubilizing raw material X contained in the growth raw material to carbon is x1:x2:x3;

[0017] (2) assembling the device so that the blocking block blocks the through hole of the first growth crucible, the external graphite cylinder is detachably connected above the graphite cylinder of the second growth crucible, and then performing liquid phase growth of silicon carbide single crystals in the first growth crucible of the device;

[0018] (3) During the growth process, the clamp is engaged in the clamping groove of the first growth crucible, and the first growth crucible is driven to rotate by the transmission device. After the growth is completed, the clamp is first controlled by the transmission device to be retracted into the inside of the external graphite cylinder, and then the blocking block is driven downward by the transmission device to be removed from the through hole of the first growth crucible, and the upper edge of the blocking block is aligned with the upper edge of the external graphite cylinder, so that the growth material in the first growth crucible flows into the second growth crucible;

[0019] (4) After the growth raw material flows into the second growth crucible, the blocking block is continuously driven by the transmission device to move downward into the through hole of the second growth crucible;

[0020] (5) weighing the mass of the silicon carbide single crystal grown by the liquid phase method as M3, and weighing the mass of the second growth crucible after removing the external graphite cylinder as M4;

[0021] (6) After the raw material is added to the second growth crucible, the crucible is recycled as the growth raw material and repeatedly used to grow the silicon carbide single crystal by the liquid phase method, thereby realizing the recycling and reuse of the raw material for the liquid phase growth of silicon carbide; the raw material is replenished according to the following formula:

[0022] M5=M1+M2-M4-M3;

[0023] M6=[x1 / (x1+x2+x3)]×M5+0.7M3;

[0024] M7=[x2 / (x1+x2+x3)]×M5;

[0025] Wherein, M5 is the mass of the growth raw material adhered to the inner wall of the first growth crucible and not flowing into the second growth crucible; M6 is the mass of the supplemented Si; and M7 is the mass of the supplemented solvent raw material X.

[0026] Compared with the prior art, the present invention has at least the following beneficial effects:

[0027] (1) The present invention changes the crucible structure, adds a liquid leakage port (through hole) and a crucible (second growth crucible) for recovering and reusing the growth raw materials, so as to realize the function of recovering the growth raw materials, thereby significantly reducing the production cost of liquid phase method growth of silicon carbide; the device for recovering and reusing the raw materials for liquid phase method growth of silicon carbide provided by the present invention can recover the growth raw materials of liquid phase method growth of silicon carbide, realize the reuse of raw materials, save costs, and ensure the quality of crystal growth of the recovered growth raw materials, thereby solving the problem in the prior art that in the growth of silicon carbide single crystals by the liquid phase method, the amount of growth raw materials used is small, but they cannot be recovered after each use, resulting in waste of resources.

[0028] (2) The present invention changes the crucible structure, arranges a slot on the bottom outer wall of the crucible, and arranges clamps that match the slot on both sides of the top of the transmission device. The transmission device controls the opening and closing of the clamps, so that when the clamps are opened and engaged in the slot, the transmission device drives the first growth crucible to rotate. This design can drive the crucible to rotate, effectively solving the problem of the crucible being unable to rotate due to the recovery of the growth raw materials, thereby avoiding the problem of affecting the quality of crystal growth due to the inability of the crucible to rotate during the growth process.

[0029] (3) The method for recycling and reusing raw materials for growing silicon carbide by a liquid phase method provided by the present invention realizes the rational use of the device for recycling and reusing raw materials for growing silicon carbide by a liquid phase method. In addition, the method of the present invention can ensure that the composition of the recycled growth raw materials is basically consistent with the composition of the growth raw materials used for the first silicon carbide single crystal growth by reasonably supplementing the raw materials, thereby ensuring that the quality of the grown crystals of the recycled growth raw materials is equivalent and achieving the purpose of recycling the growth raw materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings of the present invention are provided for illustrative purposes only, and the proportions, sizes and quantities of the various parts in the drawings may not necessarily be consistent with the actual products.

[0031] Figure 1 It is a schematic diagram of the structure of a device for recycling and reusing raw materials of silicon carbide grown by a liquid phase method provided in some specific embodiments of the present invention;

[0032] Figure 2 It is a process flow chart of a method for recycling and reusing raw materials grown by a liquid phase method of silicon carbide provided in some specific embodiments of the present invention;

[0033] Figure 3 is an appearance diagram of a silicon carbide single crystal obtained by the first silicon carbide single crystal growth in Example 1 of the present invention;

[0034] Figure 4 is an appearance diagram of a silicon carbide single crystal obtained by the second silicon carbide single crystal growth in Example 1 of the present invention;

[0035] Figure 5 This is an appearance diagram of the silicon carbide single crystal grown in Comparative Example 1 of the present invention.

[0036] In the figure: 1: first growth crucible; 2: second growth crucible; 3: blocking block; 4: transmission device; 5: graphite cylinder; 6: external graphite cylinder; 7: outer shell crucible; 8: growth raw material; 9: slot; 10: clamp. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] In a first aspect, the present invention provides a device for recycling raw materials grown by liquid phase method for silicon carbide, for example, Figure 1As shown; the device includes a first growth crucible 1, a second growth crucible 2, a transmission device 4 (also recorded as a single crystal furnace transmission device), a blocking block 3 and an external graphite cylinder 6; the first growth crucible 1 has a through hole at the bottom, and a graphite cylinder 5 is arranged around the through hole, and the graphite cylinder 5 is located inside the first growth crucible 1. In other words, the first growth crucible 1 has a through hole at the bottom, and a graphite cylinder 5 is arranged on the inner wall of the bottom of the first growth crucible 1, and the graphite cylinder 5 is located directly above the through hole, and the inner diameter of the graphite cylinder 5 matches the aperture of the through hole; the bottom outer wall of the first growth crucible 1 has two card slots 9 , the distance between the two card slots 9 is greater than the outer diameter of the external graphite cylinder 6, and the card slot 9 does not penetrate the bottom of the first growth crucible 1; the top of the transmission device 4 is connected to the blocking block 3, and the transmission device 4 is used to drive the blocking block 3 to move up and down, and the blocking block 3 is used to block the through hole; the top of the transmission device 4 is also provided with card pieces 10 that match the card slots 9 on both sides, and the transmission device 4 is also used to control the opening and closing of the card pieces 10. When the card pieces 10 are opened and engaged in the card slots 9, the transmission device 4 drives the first growth crucible 1 to rotate, and when the card pieces 10 are closed, the card pieces 10 and The card slot 9 is separated and retracted to the inside (middle) of the external graphite cylinder 6; the first growth crucible 1 is filled with growth raw material 8, and the second growth crucible 2 is a crucible for recycling growth raw materials and is located below the first growth crucible 1, and the second growth crucible 2 has the same shape and structure as the first growth crucible 1; the first growth crucible 1 is the same as the second growth crucible 2, specifically, the first growth crucible 1 and the second growth crucible 2 have the same parameters, such as shape, structure and quality; in the present invention, the through hole opened at the bottom of the first growth crucible passes through the bottom of the first growth crucible, and the through hole of the second growth crucible The through hole opened at the bottom passes through the bottom of the second growth crucible; in the present invention, the first liquid phase growth of silicon carbide is carried out in the first growth crucible 1, and after the growth raw material 8 in the first growth crucible is transferred to the second growth crucible 2, the second growth crucible 2 is used as a container for the second liquid phase growth of silicon carbide; in the present invention, the blocking block 3 is driven up and down by the transmission device 4 to block the through hole in the first growth crucible 1 or the through hole in the second growth crucible 2; when the growth raw material 8 is recovered, the external graphite cylinder 6 can be detachably connected (for example, threadedly connected) above the graphite cylinder 5 of the second growth crucible 2;In the present invention, the external graphite cylinder 6 is connected to the graphite cylinder 5, and the setting of the external graphite cylinder 6 can increase the height of the graphite cylinder 5. In the present invention, the height of the graphite cylinder 5 is, for example, lower than the height of the growth raw material 8 melted into liquid contained in the first growth crucible 1. When the silicon carbide single crystal is grown, for example, after 2 to 7 days of growth, the height of the growth raw material 8 is reduced, and the graphite cylinder 5 is higher than the height of the growth raw material 8 after growth, which makes it easier to disassemble the external graphite cylinder 6. In the present invention, the setting of the graphite cylinder and the external graphite cylinder can prevent the liquid growth raw material from flowing into the furnace along the transmission device when the growth raw material in the first growth crucible is transferred to the second growth crucible, thereby effectively protecting the transmission device and the single crystal furnace from damage, and at the same time The external graphite cylinder is detachably connected to the graphite cylinder. After the growth raw material flows into the second growth crucible, the external graphite cylinder can be easily disassembled, so that the second growth crucible with the growth raw material recovered can be conveniently used for the second growth of silicon carbide single crystal. In the present invention, the single crystal furnace transmission device is divided into two power paths, one for controlling the rotation and lifting of the transmission rod of the transmission device; the other for controlling the opening and closing of the clamp. When the clamp is engaged in the clamping slot, the first growth crucible can be driven to rotate, avoiding the problem that the crucible cannot rotate due to the recovery of the growth raw material. When the crystal growth is completed, the clamp must be controlled to close first, for example, the clamp must be closed to the inside of the external graphite cylinder, and then the blocking block must be controlled to move downward to allow the growth raw material to flow into the second growth crucible. ;

[0039] The present invention changes the crucible structure, adds a liquid leakage port (through hole) and a growth raw material recovery and reuse crucible (second growth crucible) to realize the function of recovering the growth raw material, thereby significantly reducing the production cost of liquid phase method growth of silicon carbide; the device for recovering and reusing the raw material for liquid phase method growth of silicon carbide provided by the present invention can recover the growth raw material of liquid phase method growth of silicon carbide, realize the reuse of the raw material, save costs, and ensure the crystal growth quality of the recovered growth raw material, thereby solving the problem in the prior art that in the growth of silicon carbide single crystals by the liquid phase method, the amount of growth raw material used is small, but it cannot be recovered after each use, resulting in waste of resources.

[0040] The present invention changes the crucible structure, arranges a slot on the bottom outer wall of the crucible, and arranges clamping pieces matching the slot on both sides of the top of the transmission device. The transmission device controls the opening and closing of the clamping pieces, so that when the clamping piece is opened and engaged in the slot, the transmission device drives the first growth crucible to rotate. This design can drive the crucible to rotate, effectively solving the problem of the crucible being unable to rotate due to the recovery of growth raw materials, thereby avoiding the problem of affecting the quality of crystal growth due to the failure of the crucible to rotate during the growth process.

[0041] According to some preferred embodiments, the transmission device 4 drives the blocking block 3 to move downward to remove the blocking block 3 from the through hole of the first growth crucible 1, so that the growth raw material 8 in the first growth crucible 1 flows into the second growth crucible 2. After the growth raw material 8 flows into the second growth crucible 2, the transmission device 4 continues to drive the blocking block 3 to move downward into the through hole of the second growth crucible 2, so that the upper edge of the blocking block 3 is flush with the upper edge of the bottom of the second growth crucible 2 (crucible bottom).

[0042] According to some preferred embodiments, the wall thickness of the first growth crucible 1 and the second growth crucible 2 are both 3-5 mm (e.g., 3, 3.5, 4, 4.5 or 5 mm); the inner diameter of the graphite cylinder 5 is 10-20 mm (e.g., 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 mm), the height of the graphite cylinder 5 is 10-20 mm (e.g., 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 mm); and / or the distance between the upper edge of the external graphite cylinder 6 and the bottom of the first growth crucible 1 is 5-10 mm (e.g., Such as 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5 or 10mm); in the present invention, the inner diameter of the external graphite cylinder 6 is 10-20mm, and the inner diameter of the external graphite cylinder 6 is the same as the inner diameter of the graphite cylinder 5; in the present invention, the outer diameters of the graphite cylinder 5 and the external graphite cylinder 6 can be, for example, 15-25mm, and the outer diameters of the graphite cylinder 5 and the external graphite cylinder 6 are the same; in the present invention, the interiors of the external graphite cylinder 6 and the graphite cylinder 5 are hollow, and the lower end circumference of the external graphite cylinder 6 is threadedly connected to the upper end circumference of the graphite cylinder 5.

[0043] According to some preferred embodiments, the aperture of the through hole is 10 to 20 mm (for example, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 mm); and / or the width of the blocking block 3 is 10 to 20 mm (for example, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 mm), the thickness of the blocking block 3 is 10 to 30 mm (for example, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 mm). 0, 21, 22, 23, 24, 25, 26, 27, 28, 29 or 30mm); in the present invention, the blocking block matches the through hole and is used to block the through hole; the through hole is preferably a circular through hole or a square through hole, and the corresponding blocking blocks are preferably circular blocking blocks or square blocking blocks, respectively. When the blocking block is a circular blocking block, the width of the blocking block refers to the diameter of the blocking block, and when the blocking block is a square blocking block, the width of the blocking block refers to the side length of the blocking block.

[0044] It is particularly noted that, in the present invention, the blocking block, the through hole, the circumscribed graphite cylinder and the graphite cylinder match each other, and the width of the blocking block, the aperture of the through hole and the inner diameter of the circumscribed graphite cylinder match each other. Figure 1 For example, the intervals between the blocking block and the external graphite cylinder and the graphite cylinder shown in the figure are only for more clearly illustrating the structures of the various components; preferably, the distance between the upper edge of the external graphite cylinder 6 and the bottom of the first growth crucible 1 is not greater than the thickness of the blocking block 3. When the blocking block moves downward, the external graphite cylinder is first blocked to prevent the growth raw material from flowing into the external graphite cylinder. Then the blocking block continues to move downward, for example, until the upper edge of the blocking block is flush with the upper edge of the external graphite cylinder, and the growth raw material flows into the second growth crucible. This can prevent the liquid growth raw material from flowing into the furnace along the transmission device when the growth raw material in the first growth crucible is transferred to the second growth crucible, thereby effectively protecting the transmission device and the single crystal furnace from damage.

[0045] According to some preferred embodiments, the transmission device 4 drives the blocking block 3 to move up and down with a stroke of 50 to 80 mm (eg, 50, 55, 60, 65, 70, 75 or 80 mm).

[0046] According to some preferred embodiments, the first growth crucible 1 and the second growth crucible 2 are both made of graphite; preferably, the graphite is high-purity graphite with an impurity content of less than 50 ppm; the blocking block 3 is made of graphite or silicon carbide; and / or the growth raw material 8 contains Si and a dissolution-aid raw material X, and the dissolution-aid raw material X is one or more of Al, B, Ti, Cr, Fe, Y, Yb, Pr, La, Cu, Ce, Sn, Ge, and Co.

[0047] According to some preferred embodiments, the device further comprises an outer shell crucible 7, which is sleeved on the outside of the first growth crucible 1; the lower end of the outer shell crucible 7 has a hole, and the second growth crucible 2 overlaps the outer periphery of the hole.

[0048] According to some preferred embodiments, the hole is a truncated cone shaped hole or a rectangular hole; in the present invention, the hole can ensure that the liquid growth material flows into the second growth crucible through the hole, and the growth material does not touch the crucible wall when flowing out; the upper edge diameter of the truncated cone shaped hole is 30 to 60 mm (for example, 30, 35, 40, 45, 50, 55 or 60 mm), and the lower edge diameter of the truncated cone shaped hole is 50 to 130 mm (for example, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125 or 130 mm), preferably, the lower edge diameter of the truncated cone shaped hole is larger than the upper edge diameter of the truncated cone shaped hole.

[0049] According to some preferred embodiments, the device also includes N spare growth crucibles, N ≥ 1; the N spare growth crucibles have the same shape and structure as the first growth crucible, that is, the same shape and structure as the second growth crucible; the N spare growth crucibles are successively used as growth raw material recovery and reuse crucibles to recycle and reuse the growth raw materials, so that the device for recycling and reusing liquid phase growth of silicon carbide raw materials in the present invention can achieve multiple (twice or more) recycling of the growth raw materials.

[0050] According to some specific embodiments, the device further includes a seed crystal rod (not shown in the figure) on which a seed crystal is fixed, an insulation layer (not shown in the figure) is provided on the outer side of the outer shell crucible, an induction heating device (not shown in the figure) for heating is provided on the outer side of the insulation layer, and one end of the seed crystal rod on which the seed crystal is fixed extends into the interior of the crucible body of the growth crucible, and contacts with the liquid surface of the liquid growth raw material to grow a silicon carbide single crystal. Specifically, the device further includes a crucible cover. In the present invention, the crucible cover can be recycled and matched with the first growth crucible and the second growth crucible. When the growth crucible is used for crystal growth, the first growth crucible and the crucible cover can be connected by threads, for example, and the second growth The crucible and the crucible cover can also be connected by threads; the crucible cover has an opening, and the end of the seed crystal rod fixed with the seed crystal extends into the interior of the crucible body through the opening; the end of the seed crystal rod not fixed with the seed crystal is connected to a seed crystal rod transmission device for controlling the lifting and rotation of the seed crystal rod, that is, the transmission device controls the lifting and rotation of the seed crystal; in the present invention, the first growth crucible and the second growth crucible can also be collectively referred to as growth crucibles; the present invention has no special requirements for the seed crystal, seed crystal rod, insulation layer and induction heating device, which is a conventional design in the field; the induction heating device includes an induction coil, which is coaxially arranged with the seed crystal rod, and the induction heating device heats the growth crucible by electromagnetic induction.

[0051] According to some specific embodiments, the device for recycling and reusing raw materials for growing silicon carbide by a liquid phase method of the present invention can recycle and reuse raw materials to reduce production costs, for example, Figure 1 As shown, the device comprises:

[0052] The outer shell crucible has the first growth crucible placed inside it, and the outer shell crucible does not contact the growth raw materials and can be recycled; the lower end of the outer shell crucible has a truncated cone-shaped hole, the size of which is larger than the size of the blocking block, which can ensure that the growth raw materials flow into the second growth crucible through the truncated cone-shaped hole;

[0053] The first growth crucible, as a container for crystal growth, has a hole at the bottom (i.e., a through hole at the bottom), and a cylindrical graphite thin layer (graphite cylinder) inside; the through hole can be completely blocked by a blocking block, and the upper end of the graphite cylinder is provided with a thread, which can be matched with an external graphite cylinder to increase the height; the bottom outer wall of the first growth crucible is provided with two slots, the distance between the two slots is greater than the outer diameter of the external graphite cylinder, and the slots do not penetrate the bottom of the first growth crucible;

[0054] The second growth crucible is consistent with the first growth crucible, has the same shape and structure as the first growth crucible, serves as a raw material collection device (i.e., a growth raw material recovery and reuse crucible), and becomes a second crystal growth container;

[0055] The sealing block is placed at the bottom of the first growth crucible to seal the growth raw materials from leaking, and can be moved to the second growth crucible after the growth is completed to transfer the growth raw materials from the first growth crucible to the second growth crucible;

[0056] An external graphite cylinder is externally connected to the graphite cylinder of the second growth crucible when transferring the growth raw material solution to prevent the solution from flowing into the furnace along the single crystal furnace transmission device; the external graphite cylinder can be connected to the graphite cylinders in the first growth crucible and the second growth crucible to increase the height of the graphite cylinder;

[0057] The single crystal furnace transmission device is connected to the sealing block, and the sealing block can be moved after the growth is completed, so that the growth raw material is transferred from the first growth crucible to the second growth crucible; in the present invention, the sealing block is driven by the single crystal furnace transmission device to move up and down; the top two sides of the single crystal furnace transmission device are also provided with clamps that match the slot, and the single crystal furnace transmission device is also used to control the opening and closing of the clamp. When the clamp is opened and engaged in the slot, the transmission device drives the first growth crucible to rotate, and when the clamp is closed, the clamp is separated from the slot, so that the clamp is closed to the inside of the external graphite cylinder.

[0058] In a second aspect, the present invention provides a method for recycling and reusing raw materials grown by a liquid phase method for silicon carbide, the process flow chart is as follows, for example: Figure 2 As shown, the method is carried out using the device for recycling and reusing the raw material of silicon carbide grown by the liquid phase method as described in the first aspect of the present invention, and the method comprises the following steps:

[0059] (1) The masses of the first growth crucible, the second growth crucible and the growth raw material are weighed as M1, M2 and M3 respectively; the growth raw material comprises Si and a dissolving raw material X, and the mass ratio of Si (silicon raw material) contained in the growth raw material, the dissolving raw material X contained in the growth raw material and carbon (C) is x1:x2:x3, that is, Si: dissolving raw material X:C=x1:x2:x3; in the present invention, the mass M2 of the growth raw material refers to the mass of the growth raw material when no carbon is dissolved, and the carbon (C) refers to the carbon dissolved in the liquid growth raw material at the growth temperature; at the growth temperature, the liquid growth raw material can dissolve carbon, and the mass ratio x1:x2:x3 can be obtained by the mass of the carbon dissolved in the liquid growth raw material, and those skilled in the art know that for a fixed growth temperature, the mass of the dissolved carbon in the liquid growth raw material is basically constant, and when the material of the blocking block is graphite, the mass of the carbon consumed in the crystal growth is equivalent to the mass of the carbon dissolved in the liquid growth raw material by the growth crucible (graphite crucible), the graphite cylinder and the blocking block.

[0060] (2) assembling the device so that the blocking block blocks the through hole of the first growth crucible, the external graphite cylinder is detachably connected above the graphite cylinder of the second growth crucible, and then performing liquid phase growth of silicon carbide single crystals in the first growth crucible of the device;

[0061] (3) During the growth process, the clamp is engaged in the clamping groove of the first growth crucible, and the first growth crucible is driven to rotate by the transmission device. After the growth is completed, the clamp is first controlled by the transmission device to be retracted into the inside of the external graphite cylinder, and then the blocking block is driven downward by the transmission device to be removed from the through hole of the first growth crucible, and the upper edge of the blocking block is aligned with the upper edge of the external graphite cylinder, so that the growth material in the first growth crucible flows into the second growth crucible;

[0062] (4) After the growth raw material flows into the second growth crucible, the blocking block is continuously driven by the transmission device to move downward into the through hole of the second growth crucible, that is, after the growth raw material completely flows into the second growth crucible, the blocking block is lowered by the single crystal furnace transmission device so that the upper edge of the blocking block is flush with the upper edge of the bottom of the second growth crucible;

[0063] (5) weighing the mass of the silicon carbide single crystal grown by the liquid phase method as M3, and weighing the mass of the second growth crucible after removing the external graphite cylinder as M4, that is, weighing the mass of the silicon carbide single crystal grown by the liquid phase method as M3 after cooling, and weighing the mass of the second growth crucible after removing the external graphite cylinder as M4 after cooling;

[0064] (6) After the raw materials are added to the second growth crucible, the crucible is recycled as the growth raw materials and repeatedly used to grow silicon carbide single crystals by the liquid phase method, thereby realizing the recycling and reuse of the raw materials for growing silicon carbide by the liquid phase method; in the present invention, the mass of the growth raw materials consumed is calculated in combination with the mass of the growth raw materials, Si single substance and dissolution raw material X are replenished in proportion, and the second growth crucible after replenishing Si single substance and dissolution raw material X is used as the first growth crucible, and the single crystal growth experiment is repeated to realize the recycling of the growth raw materials; in the present invention, the raw materials are replenished specifically by the following formula:

[0065] M5=M1+M2-M4-M3;

[0066] M6=[x1 / (x1+x2+x3)]×M5+0.7M3;

[0067] M7=[x2 / (x1+x2+x3)]×M5;

[0068] Wherein, M5 is the mass of the growth raw material adhered to the inner wall of the first growth crucible and not flowing into the second growth crucible; M6 is the mass of the supplemented Si (silicon raw material); and M7 is the mass of the supplemented solvent raw material X.

[0069] The method for recycling and reusing raw materials for growing silicon carbide by a liquid phase method provided by the present invention realizes the rational use of the device for recycling and reusing raw materials for growing silicon carbide by a liquid phase method, and the method of the present invention can ensure that the components of the recycled growth raw materials are basically consistent with the components of the growth raw materials used for the first silicon carbide single crystal growth by reasonably supplementing the raw materials, which can not only ensure that the quality of the grown crystals of the recycled growth raw materials is equivalent, but also achieve the purpose of recycling the growth raw materials.

[0070] According to some specific embodiments, the device for recycling and reusing the raw material for growing silicon carbide by the liquid phase method of the present invention (for example, Figure 1 The method of growing silicon carbide single crystal by liquid phase method can not only recycle the growth raw materials, thereby achieving the purpose of reducing costs, but also ensure the quality of the growth raw materials after recycling. The specific method is as follows: ① Preparation stage: a. Weigh the mass of the first growth crucible and the second growth crucible, both of which are M1, and the mass of the growth raw materials is M2; b. Connect the blocking block to the top of the single crystal furnace transmission device, and install the device for recycling and reusing the carbonized raw materials grown by liquid phase method according to Figure 1② The connection shown in the figure, the upper edge of the blocking block is flush with the upper edge of the bottom of the crucible of the first growth crucible; c. Load the growth raw material into the first growth crucible; d. Fix the seed crystal on the seed crystal rod and place it in a suitable position in the crucible. ② Heating stage: Evacuate the furnace, then fill it with protective gas, such as helium, nitrogen or argon, and then turn on the power to increase the temperature so that the growth raw material in the first growth crucible melts into liquid, and then extend the seed crystal into the growth crucible to contact the liquid growth raw material to start the growth of silicon carbide single crystal. ③ Crystal growth stage: During the crystal growth stage, control the rotation of the seed crystal to make the solution composition uniform, and at the same time control the pulling or lowering of the seed crystal to ensure that the growth environment is suitable, and during the growth process (crystal growth stage), make the card engage in the card slot of the first growth crucible, and drive the first growth crucible to rotate through the transmission device. ④Raw material recovery stage: a. Control the seed crystal to be pulled and separated from the growth raw material solution; b. First control the clamp to be retracted to the inside of the external graphite cylinder through the single crystal furnace transmission device, and then move the blocking block downward through the single crystal furnace transmission device until the upper edge of the blocking block is flush with the upper edge of the external graphite cylinder, and the growth raw material solution flows from the first growth crucible into the second growth crucible; c. After the growth raw material has completely flowed into the second growth crucible, control the single crystal furnace transmission device to move the blocking block downward until the upper edge of the blocking block is flush with the upper edge of the bottom of the second growth crucible; d. Reduce the power to cool down. ⑤Sampling stage: Separate the seed crystal rod from the single crystal furnace, take out the crystal, and weigh the mass M3 of the grown crystal (silicon carbide single crystal). ⑥ Raw material replenishment stage: a. Rotate and remove the external graphite cylinder in the second growth crucible; b. Weigh the current mass M4 of the second growth crucible after removing the external graphite cylinder; c. Calculate the mass of raw materials that need to be added and add them (the mass of element C is not added at this time, because it can be dissolved from the growth crucible and the graphite cylinder). In the present invention, when the material of the blocking block is graphite, element C can be dissolved from the growth crucible, the graphite cylinder and the blocking block. The thickness of the blocking block is relatively thick. Although there will be dissolution during the growth process, the amount of dissolution will not be large. After 2-3 growths, a blocking block can be replaced. In the present invention, the blocking block is detachably connected to the top of the transmission device; d. The second growth crucible to which the consumed mass of growth raw materials is added is used as the first growth crucible for the next growth.

[0071] The process of adding raw materials is as follows:

[0072] The growth raw material in the present invention is a recycled growth raw material, and the mass ratio of each element in the raw material needs to be kept at a certain value, that is, Si:X (where X is a dissolution-aiding raw material): C=x1:x2:x3;

[0073] Assume that the mass of the growth raw material that is adhered to the inner wall of the first growth crucible and does not flow into the second growth crucible is M5;

[0074] The mass of C element in the growth raw material is a certain value, and the C element consumed in the growing crystal is equivalent to the C element dissolved in the growth crucible and graphite cylinder or equivalent to the C element dissolved in the growth crucible, graphite cylinder and blocking block, and the mass of C element is not added;

[0075] At this time, M5 = M1 + M2 - M4 - M3;

[0076] The mass of Si to be supplemented M6 is: [x1 / (x1+x2+x3)]×M5+0.7M3; in this formula, M3 is the mass of the grown silicon carbide single crystal, wherein the mass of Si element in the silicon carbide single crystal is 0.7M3, which is also the mass consumed by silicon element, and needs to be supplemented;

[0077] The mass M7 of the supplementary dissolution-aiding raw material X is: [x2 / (x1+x2+x3)]×M5.

[0078] The present invention will be further described below by way of examples, but the protection scope of the present invention is not limited to these embodiments.

[0079] Example 1

[0080] This embodiment provides a device for recycling raw materials for growing silicon carbide by liquid phase method, and its structural schematic diagram is shown as follows: Figure 1 As shown; the device comprises:

[0081] An outer shell crucible, in which the first growth crucible is placed; the lower end of the outer shell crucible has a truncated cone-shaped hole;

[0082] The first growth crucible, as a container for crystal growth, has a through hole at the bottom, and graphite cylinders are arranged around the through hole, and the graphite cylinders are located inside the first growth crucible; the first growth crucible is used to contain growth raw materials; the through hole can be completely blocked by a blocking block, and the upper end of the graphite cylinder is provided with threads, which can be matched with an external graphite cylinder to increase the height; the growth raw materials include Si and dissolution raw materials X (Ti); the bottom outer wall of the first growth crucible is provided with two card slots, the distance between the two card slots is greater than the outer diameter of the external graphite cylinder, and the card slots do not penetrate the bottom of the first growth crucible;

[0083] The second growth crucible is consistent with the first growth crucible, has the same shape and structure as the first growth crucible, is located below the first growth crucible, is used as a crucible for recycling growth raw materials, and becomes a second crystal growth container; the second growth crucible is overlapped with the outer periphery of the truncated cone hole;

[0084] The sealing block is placed at the bottom of the first growth crucible to seal the growth raw materials from leaking, and can be moved to the second growth crucible after the growth is completed to transfer the growth raw materials from the first growth crucible to the second growth crucible;

[0085] An external graphite cylinder is externally connected to the graphite cylinder of the second growth crucible when transferring the growth raw material solution to prevent the solution from flowing into the furnace along the single crystal furnace transmission device; the external graphite cylinder can be connected to the graphite cylinders in the first growth crucible and the second growth crucible to increase the height of the graphite cylinder;

[0086] The single crystal furnace transmission device has a blocking block connected to the top, which drives the blocking block to move up and down. The blocking block is used to block the through hole. The blocking block can be moved after the growth is completed, so that the growth raw material is transferred from the first growth crucible to the second growth crucible; the blocking block is driven to move up and down by the single crystal furnace transmission device; the transmission device drives the blocking block to move downward to remove the blocking block from the through hole of the first growth crucible, so that the growth raw material in the first growth crucible flows into the second growth crucible. After the growth raw material flows into the second growth crucible, the transmission device continues The blocking block is driven to move downward into the through hole of the second growth crucible, so that the upper edge of the blocking block is flush with the upper edge of the bottom of the second growth crucible (crucible bottom); the top two sides of the single crystal furnace transmission device are also provided with clamps that match the clamping slot, and the single crystal furnace transmission device is also used to control the opening and closing of the clamping piece. When the clamping piece is opened and clamped in the clamping slot, the transmission device drives the first growth crucible to rotate. When the clamping piece is closed, the clamping piece is separated from the clamping slot, so that the clamping piece is closed to the inside of the external graphite cylinder;

[0087] The device also includes a seed crystal rod fixed with a seed crystal, and an insulation layer is provided on the outer side of the outer shell crucible, and an induction heating device for heating is provided on the outer side of the insulation layer. When growing a silicon carbide single crystal, one end of the seed crystal rod fixed with the seed crystal extends into the interior of the crucible body and contacts the liquid surface of the liquid growth raw material to grow the silicon carbide single crystal; the end of the seed crystal rod not fixed with the seed crystal is connected to a seed crystal rod transmission device for controlling the lifting and rotation of the seed crystal rod.

[0088] This embodiment also provides a method for recycling and reusing raw materials for growing silicon carbide by a liquid phase method, which is performed using the device for recycling and reusing raw materials for growing silicon carbide by a liquid phase method in this embodiment, and includes the following steps:

[0089] The device for recycling and reusing the raw material of silicon carbide grown by the liquid phase method of the present invention (for example, Figure 1The method of growing silicon carbide single crystal by liquid phase method can not only recycle the growth raw materials, thereby achieving the purpose of reducing costs, but also ensure the quality of the growth raw materials after recycling. The specific method is as follows: ① Preparation stage: a. Weigh the mass of the first growth crucible and the second growth crucible, both of which are M1, and the mass of the growth raw materials is M2; b. Connect the blocking block to the top of the single crystal furnace transmission device, and install the device for recycling and reusing the carbonized raw materials grown by liquid phase method according to Figure 1 ② The connection shown is that the upper edge of the blocking block is flush with the upper edge of the bottom of the first growth crucible; c. Load the growth raw material into the first growth crucible; d. Fix the seed crystal on the seed crystal rod and place it in a suitable position in the crucible. ② Heating stage: Evacuate the furnace, then fill it with protective gas argon, and then turn on the power to increase the temperature so that the growth raw material in the first growth crucible melts into liquid, and then extend the seed crystal into the growth crucible to contact the liquid growth raw material to start the growth of silicon carbide single crystal. ③ Crystal growth stage: During the crystal growth stage, control the rotation of the seed crystal to make the solution composition uniform, and at the same time control the pulling or lowering of the seed crystal to ensure that the growth environment is suitable, so that the growth raw material grows the first silicon carbide single crystal in the first growth crucible, and during the growth process (crystal growth stage), the card is engaged in the card slot of the first growth crucible, and the first growth crucible is driven to rotate by the transmission device. ④Raw material recovery stage: a. Control the seed crystal to be pulled and separated from the growth raw material solution; b. First control the clamp to be retracted to the inside of the external graphite cylinder through the single crystal furnace transmission device, and then move the blocking block downward through the single crystal furnace transmission device until the upper edge of the blocking block is flush with the upper edge of the external graphite cylinder, and the growth raw material solution flows from the first growth crucible into the second growth crucible; c. After the growth raw material has completely flowed into the second growth crucible, control the single crystal furnace transmission device to move the blocking block downward until the upper edge of the blocking block is flush with the upper edge of the bottom of the second growth crucible; d. Reduce the power to cool down. ⑤Sampling stage: Separate the seed crystal rod from the single crystal furnace, take out the crystal, and weigh the mass M3 of the grown crystal (silicon carbide single crystal). ⑥ Raw material replenishment stage: a. Rotate and remove the external graphite cylinder in the second growth crucible; b. Weigh the current mass M4 of the second growth crucible after removing the external graphite cylinder; c. Calculate the mass of raw materials that need to be added and add them; d. Use the second growth crucible to which the consumed mass of growth raw materials is added as the first growth crucible for the next growth, so that the growth raw materials after the replenishment of the raw materials are used in the second growth crucible for the second growth of silicon carbide single crystals.

[0090] The process of adding raw materials is as follows:

[0091] In this embodiment, the mass M1 of the first and second growth crucibles is 2.362 kg; the growth raw materials are Si and the dissolution raw material Ti, the total mass M2 is 3.688 kg, and the element mass ratio Si(x1):Ti(x2):C(x3)=4:5:1 in this system is obtained by calculation; the mass M3 of the grown silicon carbide single crystal is 0.546 kg; the growth raw materials flow into the second growth crucible and after removing the external graphite cylinder, the mass M4 of the second growth crucible is weighed to be 5.276 kg;

[0092] Assume that the mass of the growth raw material that is adhered to the inner wall of the first growth crucible and does not flow into the second growth crucible is M5;

[0093] At this time, M5 = M1 + M2 - M4 - M3 = (2.362 + 3.688 - 5.276 - 0.546) kg = 0.228 kg;

[0094] The additional Si mass M6 is: [x1 / (x1+x2+x3)]×M5+0.7M3==0.0912kg+0.3822kg=0.4734kg;

[0095] The mass M7 of the supplementary dissolution-aiding raw material X(Ti) is: [x2 / (x1+x2+x3)]×M5=0.114kg.

[0096] The appearance of the silicon carbide single crystal obtained by the first silicon carbide single crystal growth in this embodiment is as follows: Figure 3 As shown; the appearance of the silicon carbide single crystal obtained by the second silicon carbide single crystal growth in this embodiment is as shown Figure 4 shown; from Figure 3 and Figure 4 It can be seen that the quality of the first growth of the silicon carbide single crystal by the present invention is equivalent to the quality of the second growth of the silicon carbide single crystal after the growth raw materials are recovered and replenished.

[0097] During the growth of silicon carbide single crystals by the liquid phase method, the cost of raw materials for a single furnace growth accounts for about 30%, but the consumption of the raw materials for growth is extremely low during the crystal growth process, and eventually solidifies in the growth crucible in the form of mixed metal. However, since the growth crucible generally provides a C source for crystal growth in addition to being a growth container, it has a certain loss, and repeated use not only affects the temperature field, but also has the risk of melt-through. Therefore, under normal circumstances, the growth raw materials after use will be discarded as solid waste together with the growth crucible. Using the device in this embodiment to grow silicon carbide single crystals can not only ensure the quality of the crystal growth, but also achieve the reuse of the growth raw materials, compared with not using the device in the present invention to grow silicon carbide single crystals, and the cost savings per furnace can reach about 28% (of which about 2% is the cost of replenishing raw materials).

[0098] Comparative Example 1

[0099] The liquid phase method is used to grow silicon carbide in a conventional liquid phase method silicon carbide single crystal growth device. The conventional liquid phase method silicon carbide single crystal growth device includes:

[0100] An outer shell crucible, in which the growth crucible is placed; the outer shell crucible has the same size as the outer shell crucible in Example 1;

[0101] A growth crucible, as the main container for crystal growth, is used to hold growth raw materials; the growth raw materials include Si and dissolution raw materials X (Ti); the growth raw materials are the same as the growth raw materials used for the first silicon carbide single crystal growth in Example 1; the size of the growth crucible is the same as the size of the first growth crucible in Example 1, except that the through hole is not opened and the graphite cylinder is not set.

[0102] The device also includes a seed crystal rod fixed with a seed crystal, and an insulation layer is provided on the outer side of the outer shell crucible, and an induction heating device for heating is provided on the outer side of the insulation layer. When growing a silicon carbide single crystal, one end of the seed crystal rod fixed with the seed crystal extends into the interior of the crucible body and contacts the liquid surface of the liquid growth raw material to grow the silicon carbide single crystal; the end of the seed crystal rod not fixed with the seed crystal is connected to a seed crystal rod transmission device for controlling the lifting and rotation of the seed crystal rod.

[0103] The specific method of growing a silicon carbide single crystal using the conventional liquid phase method for growing a silicon carbide single crystal is as follows:

[0104] ① Prepare the growth raw materials and put them into the growth crucible;

[0105] ② Place the growth crucible in the single crystal growth furnace;

[0106] ③ Single crystal growth is performed through vacuum, heating, growth, and cooling steps; specifically, the furnace is evacuated, then filled with protective gas argon, and then the power is turned on to increase the temperature so that the growth raw material in the growth crucible is melted into liquid, and then the seed crystal is extended into the growth crucible to contact the liquid growth raw material to start the growth of silicon carbide single crystal;

[0107] ③ Crystal growth stage: During the crystal growth stage, the rotation of the seed crystal is controlled to make the solution composition uniform, and the pulling or lowering of the seed crystal is controlled to ensure a suitable growth environment so that the growth raw material can grow a silicon carbide single crystal in the growth crucible; after the growth is completed, the silicon carbide single crystal is obtained by cooling;

[0108] ④ After cooling, take out the crystal, and discard the growth raw materials and growth crucible.

[0109] The appearance of the silicon carbide single crystal grown in this comparative example is as follows: Figure 5As shown; this comparative example uses a conventional liquid phase method for growing silicon carbide using a growth device, and uses this device to grow silicon carbide single crystals. The quality of the grown crystals is equivalent to that in Example 1, but the cost is increased by about 28%.

[0110] In the description of the present invention, it should be noted that the terms "upper", "lower", "above", "below", "bottom", "inside", "outside" and the like indicate directions or positional relationships based on the attached Figure 1 The orientation or positional relationship shown is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0111] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the term "connection" 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 directly connected, or indirectly connected through an intermediate medium, etc. For ordinary technicians in this field, the specific meaning of this term in the present invention can be understood according to the specific situation.

[0112] Parts of the present invention that are not described in detail are well known to those skilled in the art.

[0113] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for recycling and reusing raw materials grown by liquid phase method for silicon carbide, It is characterized in that The method is carried out by using a device for recycling raw materials grown by a liquid phase method for silicon carbide, and the device for recycling raw materials grown by a liquid phase method for silicon carbide comprises a first growth crucible, a second growth crucible, a transmission device, a blocking block and an external graphite cylinder; a through hole is provided at the bottom of the first growth crucible, a graphite cylinder is arranged around the through hole, and the graphite cylinder is located inside the first growth crucible; two grooves are provided on the outer wall of the bottom of the first growth crucible, the distance between the two grooves is greater than the outer diameter of the external graphite cylinder, and the grooves do not penetrate the bottom of the first growth crucible; the transmission device The top of the device is connected to the blocking block, and the transmission device is used to drive the blocking block to move up and down, and the blocking block is used to block the through hole; the top two sides of the transmission device are also provided with clamps that match the slot, and the transmission device is also used to control the opening and closing of the clamps. When the clamps are opened and engaged in the slot, the transmission device drives the first growth crucible to rotate, and when the clamps are closed, the clamps are separated from the slot, and the clamps are closed to the inside of the external graphite cylinder; the first growth crucible is filled with growth raw materials, and the second growth crucible is used as The crucible for recycling growth raw materials is used as the first growth crucible for the next growth and is located below the first growth crucible, and the second growth crucible has the same shape and structure as the first growth crucible. Since the second growth crucible has the same shape and structure as the first growth crucible, two card slots are also provided on the bottom outer wall of the second growth crucible. When the second growth crucible is used as the first growth crucible for the next growth, the card pieces provided on both sides of the top of the transmission device can be opened and engaged in the card slots of the second growth crucible, and the transmission device can also drive the second growth crucible. The crucible rotates; the external graphite cylinder is detachably connected to the top of the graphite cylinder of the second growth crucible; the device for recycling and reusing raw materials for growing silicon carbide by liquid phase method also includes an outer shell crucible, which is sleeved on the outside of the first growth crucible; the lower end of the outer shell crucible has a hole, and the second growth crucible overlaps the outer periphery of the hole; the hole is a truncated cone hole, the upper edge diameter of the truncated cone hole is 30 to 60 mm, the lower edge diameter of the truncated cone hole is 50 to 130 mm, and the lower edge diameter of the truncated cone hole is larger than the upper edge diameter; The method comprises the following steps: (1) weighing the first growth crucible, the second growth crucible and the growth raw material to be M1, M1 and M2 respectively; the growth raw material comprises Si and a solubilizing raw material X, and the mass ratio of Si contained in the growth raw material, the solubilizing raw material X contained in the growth raw material to carbon is x1:x2:x3; (2) assembling the device for recycling and reusing raw materials for growing silicon carbide by the liquid phase method, so that the blocking block blocks the through hole of the first growth crucible, and the external graphite cylinder is detachably connected to the top of the graphite cylinder of the second growth crucible, and then performing liquid phase growth of silicon carbide single crystals in the first growth crucible of the device for recycling and reusing raw materials for growing silicon carbide by the liquid phase method; (3) During the growth process, the clamp is engaged in the clamping groove of the first growth crucible, and the first growth crucible is driven to rotate by the transmission device. After the growth is completed, the clamp is first controlled by the transmission device to be retracted into the inside of the external graphite cylinder, and then the blocking block is driven downward by the transmission device to be removed from the through hole of the first growth crucible, and the upper edge of the blocking block is aligned with the upper edge of the external graphite cylinder, so that the growth material in the first growth crucible flows into the second growth crucible; (4) After the growth raw material flows into the second growth crucible, the blocking block is continuously driven by the transmission device to move downward into the through hole of the second growth crucible; (5) weighing the mass of the silicon carbide single crystal grown by the liquid phase method as M3, and weighing the mass of the second growth crucible after removing the external graphite cylinder as M4; (6) After the raw materials are added to the second growth crucible, the crucible is recycled and reused as the growth raw materials, that is, it is used as the first growth crucible for the next growth to repeatedly grow the silicon carbide single crystal by the liquid phase method, thereby realizing the recycling and reuse of the raw materials for the growth of silicon carbide by the liquid phase method; when the second growth crucible after the raw materials are added is used as the first growth crucible for the next growth to repeatedly grow the silicon carbide single crystal by the liquid phase method, the clamps provided on both sides of the top of the transmission device are still opened and clamped in the clamping grooves of the second growth crucible, and the transmission device also drives the second growth crucible to rotate; the raw materials are supplemented by the following formula: M5=M1+M2-M4-M3; M6=[x1 / (x1+x2+x3)]×M5+0.7M3; M7=[x2 / (x1+x2+x3)]×M5; Wherein, M5 is the mass of the growth raw material adhered to the inner wall of the first growth crucible and not flowing into the second growth crucible; M6 is the mass of the supplemented Si; and M7 is the mass of the supplemented solvent raw material X.

2. The method according to claim 1, Features: The wall thickness of the first growth crucible and the second growth crucible are both 3-5 mm; The inner diameter of the graphite cylinder is 10 to 20 mm, and the height of the graphite cylinder is 10 to 20 mm; and / or The distance between the upper edge of the circumscribed graphite cylinder and the bottom of the first growth crucible is 5 to 10 mm.

3. The method according to claim 1, Features: The through hole has a diameter of 10 to 20 mm; and / or The width of the blocking block is 10-20 mm, and the thickness of the blocking block is 10-30 mm.

4. The method according to claim 1, Features: The travel of the blocking block driven by the transmission device to move up and down is 50 to 80 mm.

5. The method according to claim 1, Features: The first growth crucible and the second growth crucible are both made of graphite; The material of the blocking block is graphite or silicon carbide; and / or The growth raw material comprises Si and a dissolution-aiding raw material X, and the dissolution-aiding raw material X is one or more of Al, B, Ti, Cr, Fe, Y, Yb, Pr, La, Cu, Ce, Sn, Ge, and Co.

6. The method according to any one of claims 1 to 5, Features: The device for recycling and reusing raw materials grown by the liquid phase method for silicon carbide further comprises N spare growth crucibles, where N≥1; N spare growth crucibles have the same shape and structure as the first growth crucible; The N spare growth crucibles are successively used as growth raw material recovery and reuse crucibles.

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