Resistance method growth equipment and method for large-size silicon carbide single crystal

Abstract

The invention discloses resistance method growth equipment and method for large-size silicon carbide single crystals, and relates to the technical field of silicon single crystal preparation, the resistance method growth equipment comprises an inert gas introduction mechanism, the inert gas introduction mechanism comprises an integrated bottom plate, the top of the integrated bottom plate is fixedly connected with a fixing ring, and the interior of the fixing ring is fixedly connected with an inert gas cylinder; and the heating mechanism comprises a heat preservation box body, and a vacuum cavity is formed in the upper end of the heat preservation box body. Through the design of the guide cylinder combining the spiral guide groove and the cooling cavity, and the cooling flow channel in the mounting frame, the transmission path of a gas-phase substance can be optimized, the retention time of the gas-phase substance in the guide cylinder is prolonged, gas-phase molecules are distributed more uniformly, the growth quality difference between the edge and the central area of a crystal is remarkably reduced, and the crystal quality is improved. Meanwhile, the pressure is rapidly increased to 500-800 mbar in the ultrahigh-pressure rapid growth stage, the collision frequency of gas-phase molecules is greatly increased, the growth rate is remarkably increased compared with that of a traditional process, and the requirement of the market for productivity is met.

Description

Technical Field

[0001] This invention relates to the field of silicon single crystal preparation technology, specifically to a resistive growth apparatus and method for large-size silicon carbide single crystals. Background Technology

[0002] Silicon carbide (SiC), as a core material for third-generation semiconductors, plays a crucial role in fields such as power devices for new energy vehicles, RF modules for 5G base stations, and high-voltage power transmission and distribution in rail transit due to its high breakdown field strength, high electron mobility, and excellent high-temperature resistance. Large-size silicon carbide single-crystal substrates are fundamental to realizing high-performance devices, and their fabrication technology directly determines the development level of the semiconductor industry chain. Resistance growth equipment, as the core equipment for preparing silicon carbide single crystals, is crucial for improving crystal quality and production efficiency through precise control of the temperature field, gas environment, and crystal growth interface.

[0003] In the resistivity growth of large-size silicon carbide single crystals, traditional equipment suffers from low molecular transport efficiency in the gas phase under conventional growth pressure, resulting in slow growth rates that cannot meet the growing market demand. At the same time, traditional flow tube structures cannot adapt to the growth requirements of large-size crystals, and the gas phase material is prone to generating concentration gradients during transport, leading to significant differences in growth quality between the crystal edge and the center region. Therefore, a resistivity growth device and method for large-size silicon carbide single crystals is proposed. Summary of the Invention

[0004] This invention provides a resistance method and apparatus for growing large-size silicon carbide single crystals to address the problems mentioned in the background art, such as the low molecular transport efficiency of silicon carbide gas under conventional growth pressure, resulting in slow growth rates that cannot meet the growing market demand; and the inability of traditional flow tube structures to adapt to the growth requirements of large-size crystals, where concentration gradients are easily generated during gaseous material transport, leading to significant differences in growth quality between the crystal edge and the center region. Therefore, this invention proposes a resistance method and apparatus for growing large-size silicon carbide single crystals.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A resistance method for growing large-size silicon carbide single crystals includes an inert gas inlet mechanism comprising an integrated base plate with a fixing ring fixedly connected to its top and an inert gas cylinder fixedly connected inside the fixing ring; a heating mechanism comprising an insulated box with a vacuum chamber at its upper end, a graphite heating element fixedly connected to the inner wall of the vacuum chamber, and a box cover at the top of the insulated box; a large-size silicon single crystal growth mechanism comprising a cylinder with its bottom fixedly connected to the inner wall of the lower end of the insulated box, a support fixedly connected to the output end of the cylinder, and a crucible tray fixedly connected to the top of the support; and a multi-stage vacuum pumping mechanism comprising a vacuum pipe with a first one-way valve inside, a first vacuum pump at one end of the vacuum pipe, and an output pipe at the output end of the first vacuum pump.

[0006] A further improvement of the technical solution of the present invention is that the inert gas introduction mechanism further includes a gas supply pipe, and an electromagnetic valve is provided inside the gas supply pipe.

[0007] A further improvement of the technical solution of the present invention is that: the heating mechanism further includes an observation window, the observation window is disposed on the surface of the box cover, a first mounting rod is fixedly connected to the bottom of the inner cavity of the vacuum chamber, a vacuum port is disposed on the surface of the box cover, and the vacuum port is connected to the air extraction pipe.

[0008] A further improvement of the technical solution of the present invention is that: the large-size silicon single crystal growth mechanism further includes a mounting frame, the bottom of which is set on the top of the crucible tray, and a flow guide tube is bolted to the top of the mounting frame.

[0009] A further improvement of the technical solution of the present invention is that: the top of the crucible tray is provided with a crucible containing silicon carbide powder, the inside of the mounting frame is provided with a cooling channel, the lower end of the cooling channel passes through the crucible tray and the support, and the end of the cooling channel is connected to a water cooling device.

[0010] A further improvement of the technical solution of the present invention is that: the large-size silicon single crystal growth mechanism further includes a fixing plate, the fixing plate is disposed on the top of the first mounting rod, and a seed crystal is fixedly connected to the bottom of the fixing plate.

[0011] A further improvement of the technical solution of the present invention is that: the guide tube includes a cylinder body, the upper diameter of the cylinder body is larger than the lower diameter, a gas phase storage cavity is provided inside the cylinder body, and a gas phase collection hole is provided at the bottom of the inner cavity of the gas phase storage cavity.

[0012] A further improvement of the technical solution of the present invention is that: a spiral guide groove is provided at the top of the inner cavity of the gas phase storage chamber, a cooling chamber is provided inside the cylinder, an installation plate is provided at the bottom of the cylinder, a connecting hole is provided at the bottom of the installation plate, and the interior of the cooling chamber is connected to the cooling flow channel through the connecting hole.

[0013] A further improvement of the technical solution of the present invention is that: the multi-stage vacuum mechanism further includes a buffer gas tank, the interior of the buffer gas tank is connected to the output pipe, the inner wall of the buffer gas tank is connected to a second vacuum pump through a connecting pipe, and a second one-way valve is provided inside the connecting pipe.

[0014] Further improvements to the technical solution of this invention are as follows: S1; Equipment assembly and preparation: Fixing the integrated base plate, installing inert gas cylinders and related pipelines, sealing the box cover, placing the crucible containing silicon carbide powder, and fixing the guide tube; connecting the water cooling equipment and the cooling channel; connecting all components of the vacuum pumping assembly; S2; System vacuuming and leak detection: First, start the first vacuum pump to roughly pump the vacuum chamber, then start the second vacuum pump to pump gas through a buffer tank in a two-stage process, reducing the gas pressure to the growth standard; close the valve and maintain the pressure for 30 minutes, then check the system leakage rate; S3; Heating and silicon carbide raw material vaporization: Turn on the graphite heating element and heat at a rate of 5-10℃ / min. The vacuum chamber is heated to 2100-2300℃; when the temperature reaches 1800℃, inert gas is introduced to maintain a pressure of 10-100mbar; silicon carbide powder decomposes into gaseous substances at high temperature, which enter the gas phase storage chamber of the guide tube through the gas phase collection hole; S4; Ultra-high pressure rapid growth stage: when the seed crystal surface temperature stabilizes at 2150±5℃, argon gas is rapidly injected through the inert gas introduction mechanism, increasing the system pressure from 10-100mbar to 500-800mbar within 30 minutes; the water cooling equipment is started simultaneously to increase the coolant flow rate of the guide tube cooling chamber, so that the outer wall temperature of the guide tube is maintained at 800℃. -1000℃, forming a radial temperature gradient of 200-300℃; under high pressure, the gaseous material forms a stable clockwise spiral upward flow field through the spiral guide groove, extending the residence time by 20%; when the pressure increases and causes the temperature field to shift, the power of the graphite heating element is automatically adjusted, and the distance between the crucible and the seed crystal is finely adjusted by the cylinder to maintain a constant growth temperature of 2150±3℃; under a pressure of 500-800mbar, the SiC crystal growth rate is increased to 1.2-1.5mm / h, while the risk of polycrystalline formation is avoided by adjusting the argon flow rate and the cooling intensity of the guide tube; S5; gas phase transport and single crystal growth Growth: The gaseous material is uniformly distributed on the surface of the seed crystal under the action of the spiral guide groove; the water cooling equipment adjusts the flow rate of the coolant and controls the temperature of the cooling chamber of the guide tube to form an axial temperature gradient; the cylinder slowly lifts the support to maintain a constant growth interface; the temperature and pressure are monitored and adjusted through the observation window, infrared thermometer and pressure sensor; S6; Crystal annealing and cooling: After growth, in-situ annealing is carried out at 2000-2100℃ for 2-4 hours to eliminate stress; the temperature is slowly reduced to room temperature at a rate of 10-20℃ / h, and the inert gas pressure is gradually increased to atmospheric pressure; the water cooling equipment is turned off and the grown silicon carbide single crystal is taken out.

[0015] Due to the adoption of the above technical solution, the technical progress achieved by this invention compared to the prior art is as follows: This invention provides a resistance method and apparatus for growing large-size silicon carbide single crystals. Through a guide tube design combining a spiral flow channel and a cooling chamber, along with a cooling channel within the mounting frame, the transport path of the gaseous material is optimized, extending its residence time within the guide tube. This results in a more uniform distribution of gaseous molecules, significantly reducing the growth quality difference between the crystal edge and center regions. Simultaneously, during the ultra-high pressure rapid growth stage, the pressure is rapidly increased to 500-800 mbar, significantly increasing the collision frequency of gaseous molecules and resulting in a significantly higher growth rate than traditional processes, meeting market demands for production capacity. Furthermore, during the ultra-high pressure rapid growth stage, water cooling equipment controls the temperature of the guide tube, creating a radial temperature gradient. Combined with the spiral flow field, this effectively suppresses polycrystalline phenomena caused by gas phase supersaturation, ensuring crystal growth quality. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the main structure of the present invention; Figure 2 This is a side view of the present invention; Figure 3 This is a schematic diagram of the inert gas introduction mechanism of the present invention; Figure 4 This is a schematic diagram of the internal structure of the heat-insulating box of the present invention. Figure 5 This is an exploded structural diagram of the large-size silicon single crystal growth mechanism of the present invention; Figure 6 This is a cross-sectional structural diagram of the present invention; Figure 7 This is a schematic cross-sectional view of the cooling channel structure of the present invention; Figure 8 This is a cross-sectional view of the guide tube structure of the present invention. Figure 9 This is a bottom view of the guide tube structure of the present invention; Figure 10 This is a flowchart illustrating the usage method of the present invention.

[0017] In the diagram: 11. Integrated base plate; 12. Fixing ring; 13. Inert gas cylinder; 14. Gas supply pipe; 15. Solenoid valve; 21. Insulated box; 22. Vacuum chamber; 23. Graphite heating element; 24. Box cover; 25. Observation window; 27. First mounting rod; 28. Vacuum port; 31. Cylinder; 32. Support component; 33. Crucible tray; 34. Mounting frame; 35. Flow guide tube; 351. Cylinder body; 352. Gas... 353. Phase collection hole; 354. Gas phase temporary storage chamber; 355. Spiral guide groove; 356. Cooling chamber; 357. Mounting plate; 358. Connecting hole; 39. Crucible; 30. Cooling channel; 31. Fixing plate; 42. Seed crystal; 43. Evacuation pipe; 44. First one-way valve; 45. First vacuum pump; 46. Output pipe; 47. Buffer gas tank; 48. Connecting pipe; 49. Second one-way valve; 40. Second vacuum pump. Detailed Implementation

[0018] The present invention will be further described in detail below with reference to embodiments: Example 1

[0019] like Figure 1-10 As shown, this invention provides a resistive growth apparatus and method for large-size silicon carbide single crystals, including an inert gas introduction mechanism, which includes an integrated base plate 11, a fixing ring 12 fixedly connected to the top of the integrated base plate 11, and an inert gas cylinder 13 fixedly connected inside the fixing ring 12; and a heating mechanism, which includes an insulation box 21, a vacuum chamber 22 provided at the upper end of the insulation box 21, a graphite heating element 23 fixedly connected to the inner wall of the vacuum chamber 22, and a box cover 24 provided at the top of the insulation box 21. The large-size silicon single crystal growth mechanism includes a cylinder 31, the bottom of which is fixedly connected to the inner wall of the lower end of the insulation box 21, a support member 32 is fixedly connected to the output end of the cylinder 31, and a crucible tray 33 is fixedly connected to the top of the support member 32; a multi-stage vacuum pumping mechanism includes a vacuum pipe 41, a first one-way valve 42 is provided inside the vacuum pipe 41, a first vacuum pump 43 is provided at one end of the vacuum pipe 41, and an output pipe 44 is provided at the output end of the first vacuum pump 43.

[0020] In this embodiment, when preparing silicon carbide single crystals, a multi-stage vacuum mechanism is activated. The first vacuum pump 43 performs a rough evacuation of the vacuum chamber 22 to initially reduce the gas pressure inside the chamber. Subsequently, the second vacuum pump 48 performs a secondary evacuation through the buffer gas tank 45 to reduce the gas pressure to the standard required for growth. The valve is closed and the pressure is maintained for 30 minutes to detect the leakage rate and ensure the purity of the growth environment. Then, the graphite heating element 23 is turned on to heat the vacuum chamber to 2100-2300°C at a rate of 5-10°C / min. When the temperature reaches 1800°C, the inert gas is introduced through the solenoid valve 15 to maintain a pressure of 10-100 mbar. At this time, the silicon carbide powder in the crucible 36 decomposes into gaseous substances at high temperature and enters the gas phase temporary storage chamber 353 of the guide tube through the gas phase collection hole 352. Example 2

[0021] like Figure 1-10 As shown, based on Embodiment 1, the present invention provides a technical solution: Preferably, the inert gas introduction mechanism further includes a gas supply pipe 14, and an electromagnetic valve 15 is provided inside the gas supply pipe 14. The heating mechanism further includes an observation window 25, which is provided on the surface of the box cover 24. A first mounting rod 27 is fixedly connected to the bottom of the inner cavity of the vacuum chamber 22. A vacuum port 28 is provided on the surface of the box cover 24, and the vacuum port 28 is connected to the gas extraction pipe 41. The large-size silicon single crystal growth mechanism further includes a mounting frame 34, the bottom of which is provided on the top of the crucible tray 33. A guide tube 35 is bolted to the top of the mounting frame 34. A crucible 36 containing silicon carbide powder is provided on the top of the crucible tray 33. A cooling channel 37 is opened inside the mounting frame 34. The lower end of the cooling channel 37 passes through the crucible tray 33 and the support member 32. A water cooling device is externally connected to the end of the cooling channel 37. The large-size silicon single crystal growth mechanism also includes... The system includes a fixing plate 38, which is located on top of the first mounting rod 27. A seed crystal 39 is fixedly connected to the bottom of the fixing plate 38. The guide tube 35 includes a cylinder 351, the upper diameter of which is larger than the lower diameter. A gas phase storage chamber 353 is provided inside the cylinder 351. A gas phase collection hole 352 is provided at the bottom of the gas phase storage chamber 353. A spiral guide groove 354 is provided at the top of the gas phase storage chamber 353. A cooling chamber 355 is provided inside the cylinder 351. A mounting plate 356 is provided at the bottom of the cylinder 351. A connecting hole 357 is provided at the bottom of the mounting plate 356. The interior of the cooling chamber 355 is connected to the cooling channel 37 through the connecting hole. The multi-stage vacuum pumping mechanism also includes a buffer gas tank 45. The interior of the buffer gas tank 45 is connected to the output pipe 44. A second vacuum pump 48 is connected to the inner wall of the buffer gas tank 45 through a connecting pipe 46. A second one-way valve 47 is provided inside the connecting pipe 46.

[0022] In this embodiment, during the ultra-high pressure rapid growth stage, when the surface temperature of the seed crystal 39 stabilizes at 2150±5℃, the inert gas inlet mechanism rapidly injects argon gas, increasing the pressure from 10-100mbar to 500-800mbar within 30 minutes. Simultaneously, the water cooling equipment is activated, increasing the coolant flow rate of the guide tube cooling chamber 355, maintaining the outer wall of the guide tube at 800-1000℃, forming a radial temperature gradient of 200-300℃. Under high pressure, the gaseous material forms a stable clockwise spiral upward flow field under the action of the spiral guide groove 354, extending the residence time by 20% and ensuring uniform ion distribution. Example 3

[0023] like Figure 1-10As shown, based on Embodiment 1, the present invention provides a technical solution: preferably, including S1; Equipment assembly and preparation: fixing the integrated base plate, installing inert gas cylinders and related pipelines, sealing the box cover, placing the crucible containing silicon carbide powder, fixing the guide tube; connecting the water cooling equipment and the cooling channel; connecting the various components of the vacuum assembly; S2; System vacuuming and leak detection: first starting the first vacuum pump to roughly pump the vacuum chamber, then starting the second vacuum pump to pump the gas through the buffer gas tank in a two-stage process, reducing the gas pressure to the growth standard; closing the valve and maintaining the pressure for 30 minutes, and detecting the system leakage rate; S3; Heating and silicon carbide raw material vaporization: turning on the graphite heating element, at 5- The vacuum chamber is heated to 2100-2300℃ at a rate of 10℃ / min; when the temperature reaches 1800℃, inert gas is introduced to maintain a pressure of 10-100mbar; the silicon carbide powder decomposes into gaseous substances at high temperature, which enter the gas phase storage chamber of the guide tube through the gas phase collection hole; S4; Ultra-high pressure rapid growth stage: when the seed crystal surface temperature stabilizes at 2150±5℃, argon gas is rapidly injected through the inert gas introduction mechanism, increasing the system pressure from 10-100mbar to 500-800mbar within 30 minutes; the water cooling equipment is started simultaneously to increase the coolant flow rate of the guide tube cooling chamber, so that the outer wall temperature of the guide tube... The temperature is maintained at 800-1000℃, forming a radial temperature gradient of 200-300℃; under high pressure, the gaseous material forms a stable clockwise spiral upward flow field through the spiral guide channel, extending the residence time by 20%; when the pressure increases and causes the temperature field to shift, the power of the graphite heating element is automatically adjusted, and the distance between the crucible and the seed crystal is finely adjusted by the cylinder to maintain a constant growth temperature of 2150±3℃; under a pressure of 500-800mbar, the SiC crystal growth rate is increased to 1.2-1.5mm / h, while the risk of polycrystalline formation is avoided by adjusting the argon flow rate and the cooling intensity of the guide tube; S5; gas phase transport Single crystal growth: The gaseous material is uniformly distributed on the surface of the seed crystal under the action of the spiral guide groove; the water cooling equipment adjusts the flow rate of the coolant and controls the temperature of the cooling chamber of the guide tube to form an axial temperature gradient; the cylinder slowly lifts the support to maintain a constant growth interface; the temperature and pressure are monitored and adjusted through the observation window, infrared thermometer and pressure sensor; S6; Crystal annealing and cooling: After growth, in-situ annealing is carried out at 2000-2100℃ for 2-4 hours to eliminate stress; the temperature is slowly reduced to room temperature at a rate of 10-20℃ / h, and the inert gas pressure is gradually increased to atmospheric pressure; the water cooling equipment is turned off and the grown silicon carbide single crystal is taken out.

[0024] In this embodiment, the system monitors the temperature field in real time using an infrared thermometer. When pressure changes cause a shift in the temperature field, the power of the graphite heating element 23 is automatically adjusted. The distance between the crucible 36 and the seed crystal 39 is finely adjusted using cylinder 31 to maintain a constant growth temperature of 2150±3℃. During this stage, the growth rate is increased to 1.2-1.5 mm / h. Simultaneously, polycrystalline formation is suppressed by adjusting the argon gas flow rate and the cooling intensity of the guide tube 35. The water-cooling equipment continuously adjusts the coolant flow rate and controls the temperature of the guide tube cooling chamber 355, creating an environment conducive to crystal growth. The axial temperature gradient; cylinder 31 slowly lifts support 32 to maintain a stable growth interface; the operator monitors and adjusts temperature and pressure parameters in real time through observation window 25, infrared thermometer and pressure sensor. After growth, the crystal is kept at 2000-2100℃ for 2-4 hours for in-situ annealing to eliminate internal stress, and then slowly cooled to room temperature at a rate of 10-20℃ / h, while gradually increasing the inert gas pressure to atmospheric pressure. Finally, the water cooling equipment is turned off and high-quality large-size silicon carbide single crystal is taken out.

[0025] The working principle of the resistance growth equipment and method for large-size silicon carbide single crystals will be explained in detail below.

[0026] like Figure 1-10As shown, during the preparation of silicon carbide single crystals, a multi-stage vacuum pumping mechanism is activated. The first vacuum pump 43 performs a rough evacuation of the vacuum chamber 22 to initially reduce the gas pressure inside the chamber. Subsequently, the second vacuum pump 48 performs a secondary evacuation through the buffer gas tank 45 to reduce the gas pressure to the standard required for growth. The valve is closed and the pressure is maintained for 30 minutes to check the leakage rate and ensure the purity of the growth environment. Then, the graphite heating element 23 is turned on to heat the vacuum chamber to 2100-2300℃ at a rate of 5-10℃ / min. When the temperature reaches 1800℃, the inert gas is introduced through the solenoid valve 15 to maintain a pressure of 10-100 mbar. Under pressure, the silicon carbide powder in crucible 36 decomposes into gaseous substances at high temperature, which enter the gas storage chamber 353 of the guide tube through the gas collection hole 352. During the ultra-high pressure rapid growth stage, when the surface temperature of the seed crystal 39 stabilizes at 2150±5℃, the inert gas inlet mechanism rapidly injects argon gas, increasing the pressure from 10-100 mbar to 500-800 mbar within 30 minutes. Simultaneously, the water cooling equipment is started, increasing the coolant flow rate in the guide tube cooling chamber 355, maintaining the outer wall of the guide tube at 800-1000℃, forming a radial temperature gradient of 200-300℃. Under high pressure, the gaseous material forms a stable clockwise spiral upward flow field under the action of the spiral guide channel 354, extending the residence time by 20% and ensuring uniform ion distribution. The system monitors in real time with an infrared thermometer. When pressure changes cause temperature field shifts, the power of the graphite heating element 23 is automatically adjusted, and the distance between the crucible 36 and the seed crystal 39 is finely adjusted by the cylinder 31 to maintain a constant growth temperature of 2150±3℃. During this stage, the growth rate is increased to 1.2-1.5mm / h. At the same time, polycrystalline formation is suppressed by adjusting the argon gas flow rate and the cooling intensity of the guide tube 35, and the water cooling equipment continuously adjusts the coolant flow rate. The temperature of the cooling chamber 355 of the guide tube is controlled to form an axial temperature gradient conducive to crystal growth; the cylinder 31 slowly lifts the support 32 to maintain a stable growth interface; the operator monitors and adjusts the temperature and pressure parameters in real time through the observation window 25, infrared thermometer and pressure sensor. After growth, the crystal is kept at 2000-2100℃ for 2-4 hours for in-situ annealing to eliminate internal stress, and then slowly cooled to room temperature at a rate of 10-20℃ / h, while the inert gas pressure is gradually increased to atmospheric pressure. Finally, the water cooling equipment is turned off and the high-quality large-size silicon carbide single crystal is taken out.

[0027] The present invention has been described in detail above. However, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, any modifications or improvements that do not depart from the spirit of the present invention are within the scope of protection of the present invention.

Claims

1. A resistive growth apparatus for large-size silicon carbide single crystals, characterized in that: include An inert gas inlet mechanism includes an integrated base plate (11), a fixing ring (12) is fixedly connected to the top of the integrated base plate (11), and an inert gas cylinder (13) is fixedly connected inside the fixing ring (12). The heating mechanism includes an insulated box (21), a vacuum chamber (22) is provided at the upper end of the insulated box (21), a graphite heating element (23) is fixedly connected to the inner wall of the vacuum chamber (22), and a box cover (24) is provided at the top of the insulated box (21). A large-size silicon single crystal growth mechanism includes a cylinder (31), the bottom of which is fixedly connected to the inner wall of the lower end of the heat preservation box (21), a support member (32) is fixedly connected to the output end of the cylinder (31), and a crucible tray (33) is fixedly connected to the top of the support member (32). A multi-stage vacuum pumping mechanism is provided, including a vacuum pipe (41), a first one-way valve (42) is provided inside the vacuum pipe (41), a first vacuum pump (43) is provided at one end of the vacuum pipe (41), and an output pipe (44) is provided at the output end of the first vacuum pump (43).

2. The resistance method growth equipment for large-size silicon carbide single crystals according to claim 1, characterized in that: The inert gas inlet mechanism also includes a gas supply pipe (14), and a solenoid valve (15) is provided inside the gas supply pipe (14).

3. The resistance method growth equipment for large-size silicon carbide single crystals according to claim 1, characterized in that: The heating mechanism also includes an observation window (25), which is located on the surface of the box cover (24). A first mounting rod (27) is fixedly connected to the bottom of the inner cavity of the vacuum chamber (22). A vacuum port (28) is provided on the surface of the box cover (24), and the vacuum port (28) is connected to the air extraction pipe (41).

4. The resistance method growth equipment for large-size silicon carbide single crystals according to claim 1, characterized in that: The large-size silicon single crystal growth mechanism also includes a mounting frame (34), the bottom of which is located on top of the crucible tray (33), and a guide tube (35) is bolted to the top of the mounting frame (34).

5. The resistance method growth apparatus for large-size silicon carbide single crystals according to claim 4, characterized in that: The crucible tray (33) is provided with a crucible (36) containing silicon carbide powder on its top. The mounting frame (34) has a cooling channel (37) inside. The lower end of the cooling channel (37) passes through the crucible tray (33) and the support (32). The end of the cooling channel (37) is connected to a water cooling device.

6. The resistance method growth apparatus for large-size silicon carbide single crystals according to claim 1, characterized in that: The large-size silicon single crystal growth mechanism also includes a fixing plate (38), which is located on the top of the first mounting rod (27), and a seed crystal (39) is fixedly connected to the bottom of the fixing plate (38).

7. The resistance method growth apparatus for large-size silicon carbide single crystals according to claim 4, characterized in that: The guide tube (35) includes a tube body (351), the upper diameter of the tube body (351) is larger than the lower diameter, a gas phase storage cavity (353) is provided inside the tube body (351), and a gas phase collection hole (352) is provided at the bottom of the inner cavity of the gas phase storage cavity (353).

8. The resistance method growth apparatus for large-size silicon carbide single crystals according to claim 7, characterized in that: The top of the gas phase storage chamber (353) is provided with a spiral guide groove (354), the inside of the cylinder (351) is provided with a cooling chamber (355), the bottom of the cylinder (351) is provided with a mounting plate (356), the bottom of the mounting plate (356) is provided with a connecting hole (357), and the inside of the cooling chamber (355) is connected to the cooling channel (37) through the connecting hole.

9. The resistance method growth apparatus for large-size silicon carbide single crystals according to claim 1, characterized in that: The multi-stage vacuum mechanism also includes a buffer tank (45), the interior of which is connected to the output pipe (44), and the inner wall of the buffer tank (45) is connected to a second vacuum pump (48) through a connecting pipe (46). A second one-way valve (47) is provided inside the connecting pipe (46).

10. A method using a resistance method growth apparatus for large-size silicon carbide single crystals as described in any one of claims 1-9, characterized in that: include S1; Equipment assembly and preparation: Fix the integrated base plate, install inert gas cylinders and related pipelines, seal the box cover, place the crucible containing silicon carbide powder, fix the guide tube; connect the water cooling equipment and the cooling channel; connect all components of the vacuum assembly; S2; System vacuuming and leak detection: First, start the first vacuum pump to roughly pump the vacuum chamber, then start the second vacuum pump to pump air through the buffer tank in two stages to reduce the air pressure to the growth standard; close the valve and maintain the pressure for 30 minutes to detect the system leakage rate; S3; Heating and silicon carbide raw material gasification: Turn on the graphite heating element and heat the vacuum chamber to 2100-2300℃ at a rate of 5-10℃ / min; when the temperature reaches 1800℃, introduce inert gas to maintain the pressure at 10-100mbar; the silicon carbide powder decomposes into gaseous substances at high temperature and enters the gas phase temporary storage chamber of the guide tube through the gas phase collection hole. S4; Ultra-high pressure rapid growth stage: When the seed crystal surface temperature stabilizes at 2150±5℃, argon gas is rapidly injected through the inert gas inlet mechanism, increasing the system pressure from 10-100mbar to 500-800mbar within 30 minutes; simultaneously, the water cooling equipment is started to increase the coolant flow rate of the guide tube cooling chamber, maintaining the outer wall temperature of the guide tube at 800-1000℃, forming a radial temperature gradient of 200-300℃; under high pressure, the gaseous material forms a stable clockwise spiral upward flow field through the spiral guide groove, extending the residence time by 20%; when the pressure increase causes the temperature field to shift, the power of the graphite heating element is automatically adjusted, and the distance between the crucible and the seed crystal is finely adjusted by the cylinder to maintain a constant growth temperature of 2150±3℃; under a pressure of 500-800mbar, the SiC crystal growth rate increases to 1.2-1.5mm / h, while the risk of polycrystalline formation is avoided by adjusting the argon gas flow rate and the cooling intensity of the guide tube; S5; Gas phase transport and single crystal growth: Gas phase material is uniformly distributed on the surface of the seed crystal under the action of spiral guide groove; water cooling equipment adjusts the flow rate of coolant and controls the temperature of the cooling chamber of guide tube to form an axial temperature gradient; cylinder slowly lifts the support to maintain a constant growth interface; temperature and pressure are monitored and adjusted through observation window, infrared thermometer and pressure sensor. S6; Crystal Annealing and Cooling: After growth, anneal in situ at 2000-2100℃ for 2-4 hours to relieve stress; slowly cool to room temperature at a rate of 10-20℃ / h, while simultaneously increasing the inert gas pressure to atmospheric pressure; turn off the water cooling equipment and remove the grown silicon carbide single crystal.

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