A thermal field device for silicon carbide crystal growth

Abstract

This invention discloses a silicon carbide crystal growth thermal field device, relating to the field of crystal growth thermal field technology, including a vacuum chamber and a growth mechanism. The growth mechanism includes a base, a crucible body, a crucible support, a crucible cover, a seed crystal, a seed crystal plate, a rigid support component, a fixing ring, and a flexible support structure. The rigid support component, fixing ring, flexible support structure, guide rod, guide block, first buffer spring, and reinforcing block work together to provide flexible support for the crucible support and rigid support for the crucible body, avoiding crucible tilting caused by crucible support creep, reducing thermal stress caused by uneven temperature, ensuring the fixed position of the crucible body, and avoiding spiral dislocations caused by excessive supersaturation. By adopting a combination design of flexible and rigid support, and through the synergy of stress release and position fixation, the dual goals of suppressing creep and ensuring accuracy are achieved in a high-temperature environment, thereby improving the growth effect of silicon carbide crystals.

Description

Technical Field

[0001] This invention belongs to the field of crystal growth thermal field technology, specifically a silicon carbide crystal growth thermal field device. Background Technology

[0002] Silicon carbide is an inorganic non-metallic compound composed of silicon (Si) and carbon (C), with the molecular formula SiC. It is used in the chemical, electrical, and semiconductor fields. Silicon carbide crystals are compound crystals with specific crystal structures formed by silicon (Si) and carbon (C) bonded together by covalent bonds. They possess excellent physical, chemical, and electrical properties and play an important role in many high-tech fields. The silicon carbide crystal growth thermal field device is a core equipment component used in the preparation of silicon carbide single crystals (such as 4H-SiC and 6H-SiC). By precisely controlling the temperature field distribution, it achieves high-quality crystal growth. Its design directly affects the crystal growth rate, defect density, and size uniformity, and is a key link in mainstream preparation technologies such as physical vapor transport (PVT).

[0003] Existing silicon carbide crystal growth thermal field devices have certain drawbacks. These devices typically use a crucible body and a crucible support for silicon carbide crystal growth. The crucible support is usually a single-column rigid structure, with thermal stress concentrated at the bottom connection point. Furthermore, this single-column rigid structure is usually made of graphite, which has insufficient creep resistance. This causes the crucible support to creep at high temperatures, increasing the crucible's tilt angle and causing the crystal growth direction to deviate, resulting in crystal defects. This reduces the efficiency of silicon carbide crystal growth thermal field devices, causing economic losses and failing to meet user needs. Summary of the Invention

[0004] The present invention aims to solve the technical problems existing in the prior art; to this end, the present invention proposes a thermal field device based on silicon carbide crystal growth.

[0005] A silicon carbide crystal growth thermal field device includes: a vacuum chamber and a growth mechanism disposed inside the vacuum chamber; an induction heating structure for heating the growth mechanism is disposed outside the vacuum chamber; the growth mechanism includes a base disposed inside the vacuum chamber, a crucible body movably disposed above the base for silicon crystal growth, a crucible support connected to and supporting the crucible body, and a crucible cover disposed at the upper end of the crucible body and sealed to the crucible body; the growth mechanism also includes a seed crystal movably disposed inside the crucible body for silicon crystal growth, a seed crystal plate connected to the seed crystal, and a lifting assembly disposed on the crucible cover for controlling the up-and-down movement of the seed crystal plate; the growth mechanism also includes a rigid support rotatably disposed on the base and rigidly connected to the crucible body, a fixing ring disposed outside the rigid support and connected to the crucible support, and several sets of flexible support structures arranged in a circular array on the fixing ring and flexibly connected; the rigid support, fixing ring, and flexible support structures are all made of high-temperature resistant material; and a heat insulation layer is disposed inside the vacuum chamber.

[0006] As a further aspect of the present invention: the bottom of the crucible body and the bottom of the crucible support are both provided with a convex surface structure, which can guide the flow direction of the melt and reduce the deposition of impurities at the bottom; the inner wall of the fixing ring is in contact with the outer wall of the crucible support.

[0007] As a further embodiment of the present invention: the flexible support structure includes a support rod that is perpendicularly fixed to the fixed ring, a support arm that is rotatably connected to the support rod, and a support seat that is disposed on the base and elastically connected to the support arm; the support seat is provided with an elastic component that is connected to the support arm.

[0008] As a further aspect of the present invention: the elastic component includes several sets of guide rods symmetrically arranged inside the support base, two sets of guide blocks movably arranged on the guide rods, and several sets of first buffer springs sleeved on the guide rods and respectively connected to the guide blocks and the support base; a reinforcing block connected to the support arm is provided at the upper end of the guide block; both ends of the support arm are provided with rotating grooves, and rotating blocks are provided on the inner walls of the rotating grooves; several sets of rotating blocks are respectively connected to the reinforcing blocks and the support rods.

[0009] As a further aspect of the present invention: the growth mechanism further includes a rotating component disposed on the base and controlling the rotation of the crucible body and the crucible support respectively; the rotating component is connected to a rigid support member and a flexible support structure respectively; the base is provided with a groove for the rotation of the rotating component.

[0010] As a further aspect of the present invention: the rotating assembly includes a rotating block rotatably mounted on the base and connected to the bottom end of a rigid support member, and a rotating ring disposed outside the rotating block and connected to a flexible support structure; the rotating assembly also includes a main gear rotatably mounted on the base and connected to the rotating block, several sets of driven gears respectively meshing with the main gear and rotatably mounted on the lower end face of the rotating ring, and a transmission gear ring disposed outside the driven gear and meshing with the driven gear; the base is provided with a first driving structure for controlling the rotation of the main gear, the main gear drives the crucible body to rotate through the rotating block and the rigid support member, and the driven gear drives the crucible support to rotate through the rotating ring, so that complex shear flow is generated inside the melt inside the crucible body, promoting uniform distribution of solute and reducing crystal defects.

[0011] As a further aspect of the present invention: the support rod is provided with a vibration damping component for the flexible support structure to avoid fatigue fracture caused by resonance. The support rod includes a first reinforcing rod and a second reinforcing rod respectively connected to both ends of the vibration damping component. The first reinforcing rod is connected to a fixing ring, and the second reinforcing rod is connected to a support arm. The first reinforcing rod is configured as a cylindrical structure, and the second reinforcing rod is configured as a cuboid structure.

[0012] As a further aspect of the present invention: the vibration damping assembly includes vibration damping plates connected to the first reinforcing rod and the second reinforcing rod respectively, and a multi-layer corrugated connecting pipe disposed between the two sets of vibration damping plates and adjustable in distance between the two sets of vibration damping plates, wherein both ends of the multi-layer corrugated connecting pipe are connected to the two sets of vibration damping plates respectively; the vibration damping assembly also includes several sets of electrically driven lifting structures vertically disposed between the two sets of vibration damping plates and a second buffer spring sleeved on the outside of the electrically driven lifting structure and connected to the two sets of vibration damping plates respectively, wherein both ends of the electrically driven lifting structure are connected to the two sets of vibration damping plates respectively; the several sets of electrically driven lifting structures are arranged in a circular array, and the electrically driven lifting structures are configured as high-temperature resistant products.

[0013] As a further embodiment of the present invention: the lifting assembly includes a first lead screw transmission device detachably disposed on the bottom end face of the crucible cover, a protective tube connected to the first lead screw transmission device, a transmission structure disposed on the outside of the crucible cover and controlling the first lead screw transmission device to work, a second drive structure for controlling the transmission structure to be fixed, and a protective frame disposed on the outside of the crucible cover and providing heat insulation protection for the second drive structure. The protective frame is made of heat-insulating material, and the bottom end of the protective tube is connected to the upper end face of the seed crystal plate.

[0014] As a further aspect of the present invention: the transmission structure includes a heat-insulating protective rod disposed on the first lead screw transmission device and passing through the crucible cover, a heat-insulating connecting pipe detachably mounted on the output shaft of the second drive structure, and several sets of heat-insulating connecting blocks disposed on the outer wall of the heat-insulating protective rod and connected to the heat-insulating connecting pipe. The bottom end of the heat-insulating connecting pipe is provided with several sets of connecting grooves connected to the heat-insulating connecting blocks, and the upper end face of the heat-insulating connecting block is aligned with the top end of the heat-insulating protective rod. The second drive structure is configured as a dual-axis motor, and the outer wall of the second drive structure is provided with a connecting ring movably connected to the protective frame. Several sets of weight-reducing grooves are provided on the connecting ring.

[0015] As a further aspect of the present invention, the lifting assembly further includes several sets of second lead screw transmission devices arranged in a circular array on the protective frame for controlling the lifting of the connecting ring, and a reinforcing heat insulation block arranged on the second lead screw transmission device and connected to the connecting ring.

[0016] As a further aspect of the present invention, the lifting assembly further includes an electric telescopic rod coaxially connected to the second lead screw transmission device, a first lifting gear mounted on the upper end of the electric telescopic rod, and a second lifting gear detachably mounted on the output shaft of the second drive structure and meshing with several sets of first lifting gears.

[0017] Compared with the prior art, the beneficial effects of the present invention are:

[0018] (1) The present invention, through the vacuum chamber and growth mechanism, uses rigid support, fixed ring, flexible support structure, guide rod, guide block, first buffer spring and reinforcement block to flexibly support the crucible support and rigidly support the crucible body. The flexible support avoids crucible tilting caused by crucible support creep and reduces thermal stress caused by uneven temperature. The rigid support ensures the position of the crucible body is fixed and avoids spiral dislocation caused by excessive oversaturation. By adopting the combination design of flexible support and rigid support, through the synergy of stress release and position fixation, the dual goals of suppressing creep and ensuring accuracy are achieved in high temperature environment, thereby improving the silicon carbide crystal growth effect, reducing people's economic losses and improving the use effect of silicon carbide crystal growth thermal field device.

[0019] (2) The present invention uses a rotating assembly, a first driving structure, a main gear, a rotating block and a rigid support to drive the crucible body to rotate, so that the crucible cover drives the seed crystal through the seed crystal plate, thereby improving the growth effect of silicon carbide crystal. The main gear, the driven gear, the rotating ring, the flexible support structure, the elastic component and the fixed ring drive the crucible support to rotate. The crucible body and the crucible support can form different relative rotation modes through the difference in the transmission ratio of the main and driven gears, so that complex shear flow will be generated inside the melt, which promotes uniform distribution of solute, reduces crystal defects, and adapts to the process requirements of different growth stages. The two combine to form a spiral fluid motion, which breaks the temperature gradient stratification in the thermal field. The dual-axis rotation destroys the solute boundary layer through the shear flow, reducing the risk of crystal cracking. The main gear directly drives the crucible body through the rigid support and bears the main torque. The driven gear drives the support through the rotating ring. The two kinematic chains are independent, avoiding transmission jamming caused by sudden load changes. With the use of a damping plate, a multi-layer corrugated connecting pipe and a second buffer spring, the natural frequency is changed to avoid the gear meshing frequency range and extend the service life of the flexible support structure. Attached Figure Description

[0020] Figure 1 This is an overall structural diagram of the present invention.

[0021] Figure 2 This is a cross-sectional view of the vacuum chamber and growth mechanism in this invention.

[0022] Figure 3 This is a partial structural diagram of the crucible support and flexible support structure in this invention.

[0023] Figure 4 This is a partial structural diagram of the flexible support structure and elastic components in this invention.

[0024] Figure 5 This is a partial structural diagram of the rotating component and rigid support in this invention.

[0025] Figure 6 This is a partial structural diagram of the rotating component and the first driving structure in this invention.

[0026] Figure 7 In this invention Figure 2 Enlarged view of point A in the middle.

[0027] Figure 8 This is a partial structural diagram of the lifting assembly and seed crystal plate in this invention.

[0028] Figure 9 This is a partial structural diagram of the second lifting gear and the second lead screw transmission device in this invention.

[0029] In the diagram: 1. Vacuum chamber; 2. Induction heating structure; 3. Base; 4. Crucible body; 5. Crucible support; 6. Crucible lid; 7. Seed crystal; 8. Rigid support; 9. Fixing ring; 10. Flexible support structure; 11. Support rod; 12. Support arm; 13. Support base; 14. Guide rod; 15. Guide block; 16. First buffer spring; 17. Reinforcing block; 18. Seed crystal plate; 19. Rotating block; 20. Rotating ring; 21. Main gear; 22. Driven gear; 23. Transmission gear ring; 24. First drive structure; 25. Vibration damping plate; 26. Multi-layer corrugated connecting pipe; 27. Electric lifting structure; 28. Second buffer spring; 29. ​​Transmission structure; 30. Second drive structure; 31. Protective frame; 32. Heat-insulating protective rod; 33. Heat-insulating connecting pipe; 34. Heat-insulating connecting block; 35. Connecting ring; 36. Second lead screw transmission device; 37. Reinforced heat insulation block; 38. Electric telescopic rod; 39. First lifting gear; 40. Second lifting gear; 41. First lead screw transmission device; 42. Protective pipe; 43. Insulation layer; 44. First reinforcing rod; 45. Second reinforcing rod. Detailed Implementation

[0030] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0031] Example 1

[0032] Please see Figure 1 - Figure 4This application provides a silicon carbide crystal growth thermal field device, including: a vacuum chamber 1 and a growth mechanism disposed inside the vacuum chamber 1. An induction heating structure 2 for heating the growth mechanism is disposed outside the vacuum chamber 1. The growth mechanism includes a base 3 disposed inside the vacuum chamber 1, a crucible body 4 movably disposed above the base 3 for silicon crystal growth, a crucible support 5 connected to and supporting the crucible body 4, and a crucible cover 6 disposed on the upper end of the crucible body 4 and sealed to the crucible body 4. The growth mechanism also includes a seed disposed movably inside the crucible body 4 for silicon crystal growth. The growth mechanism includes a seed crystal 7, a seed crystal plate 18 connected to the seed crystal 7, and a lifting assembly set on the crucible cover 6 to control the up and down movement of the seed crystal plate 18. The seed crystal 7 becomes the growth area for silicon carbide crystals. The growth mechanism also includes a rigid support 8 rotatably set on the base 3 and rigidly connected to the crucible body 4, a fixing ring 9 set on the outside of the rigid support 8 and connected to the crucible support 5, and several sets of flexible support structures 10 arranged in a circular array on the fixing ring 9 and flexibly connected. The rigid support 8, the fixing ring 9 and the flexible support structure 10 are all made of high-temperature resistant material. The vacuum chamber 1 is equipped with a heat insulation layer 43.

[0033] In this embodiment, the raw material is placed into the crucible body 4, and the crucible cover 6 is sealed to the crucible body 4. The rigid support 8, the fixing ring 9 and the flexible support structure 10 work together to stably support the crucible body 4 and the crucible support 5. The lifting assembly is activated, the height position of the seed crystal 7 is controlled by the seed crystal plate 18, and the crucible body 4 is heated by the induction heating structure 2, so that the raw material is heated and silicon carbide crystals are grown on the seed crystal plate 18.

[0034] In this invention, the bottom of the crucible body 4 and the bottom of the crucible support 5 are both designed with a convex surface structure, which can guide the flow direction of the melt and reduce the deposition of impurities at the bottom. The inner wall of the fixing ring 9 is in contact with the outer wall of the crucible support 5.

[0035] In this invention, the flexible support structure 10 includes a support rod 11 that is vertically fixed to the fixed ring 9, a support arm 12 that is rotatably connected to the support rod 11, and a support seat 13 that is disposed on the base 3 and elastically connected to the support arm 12; the support seat 13 is provided with an elastic component that is connected to the support arm 12.

[0036] In this invention, the elastic component includes several sets of guide rods 14 symmetrically arranged inside the support base 13, two sets of guide blocks 15 movably arranged on the guide rods 14, and several sets of first buffer springs 16 sleeved on the guide rods 14 and respectively connected to the guide blocks 15 and the support base 13. The support rods 11, the support base 13, and the guide blocks 15 are all made of heat-insulating material. The upper end of the guide block 15 is provided with a reinforcing block 17 connected to the support arm 12. Both ends of the support arm 12 are provided with rotating grooves, and the inner walls of the rotating grooves are provided with rotating blocks. Several sets of rotating blocks are respectively connected to the reinforcing blocks 17 and the support rods 11. The first buffer springs 16 are high-temperature resistant springs.

[0037] In this embodiment, the top end of the rigid support member 8 passes through the crucible support 5 and is connected to the crucible body 4. The top end of the support rod 11 is installed on the fixing ring 9. The two ends of the support arm 12 are connected to the support rod 11 and the reinforcing block 17 respectively. This allows the support rod 11, support arm 12, reinforcing block 17, guide block 15 and first buffer spring 16 to work together to provide flexible support for the crucible support 5, preventing the crucible support 5 from creeping at high temperatures, which would cause the crucible body 4 to tilt, the crystal growth direction to deviate, and crystal defects to form.

[0038] Example 2

[0039] Reference Figure 1 - Figure 6 This is the second embodiment of the present invention. In this embodiment, the growth mechanism further includes a rotating component disposed on the base 3 and controlling the rotation of the crucible body 4 and the crucible support 5 respectively. The rotating component is connected to the rigid support 8 and the flexible support structure 10 respectively. The base 3 is provided with a groove for the rotation of the rotating component.

[0040] In this invention, the rotating assembly includes a rotating block 19 rotatably mounted on a base 3 and connected to the bottom end of a rigid support member 8, and a rotating ring 20 disposed outside the rotating block 19 and connected to a flexible support structure 10. The rotating assembly also includes a main gear 21 rotatably mounted on the base 3 and connected to the rotating block 19, several sets of driven gears 22 respectively meshing with the main gear 21 and rotatably mounted on the lower end face of the rotating ring 20, and a transmission gear ring 23 disposed outside the driven gears 22 and meshing with the driven gears 22. The base 3 is provided with a first drive structure 24 for controlling the rotation of the main gear 21. The main gear 21 drives the crucible body 4 to rotate through the rotating block 19 and the rigid support member 8, and the driven gears 22 drive the crucible support 5 to rotate through the rotating ring 20. This causes complex shear flow to be generated inside the melt inside the crucible body 4, promoting uniform distribution of solute and reducing crystal defects.

[0041] In this embodiment, the first drive structure 24 is activated, causing the main gear 21 to drive the rotating block 19 to rotate, which in turn drives the rigid support member 8 to rotate. The rigid support member 8 drives the crucible body 4 to rotate, which in turn drives the crucible cover 6 to rotate. The crucible cover 6 then drives the seed crystal plate 18 to rotate via the lifting assembly, which in turn drives the seed crystal 7 to rotate, thus improving the growth effect of silicon carbide crystals. The rotation of the main gear 21 drives several sets of driven gears 22 to rotate, which in turn drives the rotating ring 20 to rotate. The rotating ring 20 then drives the crucible support 5 to rotate via the flexible support structure 10 and the fixed ring 9, thereby promoting the uniform distribution of raw material solute and reducing crystal defects.

[0042] In this invention, the support rod 11 is provided with a vibration damping component to prevent the flexible support structure 10 from fatigue fracture caused by resonance. If the meshing frequency of the planetary gear is close to the natural frequency of the support structure, resonance may be caused, which reduces the service life of the flexible support structure 10. The vibration damping component protects the flexible support structure 10. The support rod 11 includes a first reinforcing rod 44 and a second reinforcing rod 45 that are respectively connected to both ends of the vibration damping component. The first reinforcing rod 44 is connected to the fixing ring 9, and the second reinforcing rod 45 is connected to the support arm 12. The first reinforcing rod 44 is set as a cylindrical structure, and the second reinforcing rod 45 is set as a cuboid structure.

[0043] The vibration damping assembly of this invention includes damping plates 25 connected to the first reinforcing rod 44 and the second reinforcing rod 45 respectively, and a multi-layer corrugated connecting pipe 26 disposed between the two sets of damping plates 25 and adjustable in distance between them. The two ends of the multi-layer corrugated connecting pipe 26 are connected to the two sets of damping plates 25 respectively. The multi-layer corrugated connecting pipe 26 converts concentrated bending moments into axial tensile / compression + membrane stress, improving stress distribution uniformity and meeting fatigue limit requirements. Interlayer friction and material plastic deformation of the multi-layer corrugated connecting pipe 26 can generate additional damping to suppress vibration amplitude. The vibration damping assembly also includes several sets of electrically operated lifting structures 27 vertically disposed between the two sets of damping plates 25 and second buffer springs 28 sleeved on the outside of the electrically operated lifting structures 27 and connected to the two sets of damping plates 25 respectively. The electrically operated lifting structures 27 and the second buffer springs 28 cooperate to adjust the distance between the two sets of damping plates 25. The two ends of the electrically operated lifting structures 27 are connected to the two sets of damping plates 25 respectively. The several sets of electrically operated lifting structures 27 are arranged in a circular array, and the electrically operated lifting structures 27 are designed to be high-temperature resistant.

[0044] In this embodiment, when the first reinforcing rod 44 is subjected to a vertical force, the force is transmitted to the multi-layer corrugated connecting pipe 26 through the damping plate 25, and the electric lifting structure 27 is activated, so that the two sets of damping plates 25 move, changing the natural frequency and avoiding the gear meshing frequency range.

[0045] Example 3

[0046] Reference Figure 2 and Figure 7 - Figure 9 This is the third embodiment of the present invention. In this embodiment, the lifting assembly includes a first lead screw transmission device 41 detachably disposed on the bottom end face of the crucible cover 6, a protective tube 42 connected to the first lead screw transmission device 41, a transmission structure 29 disposed on the outside of the crucible cover 6 and controlling the operation of the first lead screw transmission device 41, a second drive structure 30 for controlling the transmission structure 29 to be fixed, and a protective frame 31 disposed on the outside of the crucible cover 6 and providing heat insulation protection for the second drive structure 30. The protective frame 31 is made of heat-insulating material, and the bottom end of the protective tube 42 is connected to the upper end face of the seed crystal plate 18.

[0047] In this embodiment, when it is necessary to adjust the height position of the seed crystal plate 18, the second drive structure 30 is activated, which drives the transmission structure 29 to rotate, so that the transmission structure 29 drives the first lead screw transmission device 41 to work, so that the first lead screw transmission device 41 drives the protective tube 42 to rise and fall, so that the protective tube 42 drives the seed crystal plate 18 to move up and down, thereby adjusting the height position of the seed crystal plate 18.

[0048] In this invention, the transmission structure 29 includes a heat-insulating protective rod 32 mounted on the first lead screw transmission device 41 and passing through the crucible cover 6, a heat-insulating connecting pipe 33 detachably mounted on the output shaft of the second drive structure 30, and several sets of heat-insulating connecting blocks 34 mounted on the outer wall of the heat-insulating protective rod 32 and connected to the heat-insulating connecting pipe 33. The bottom end of the heat-insulating connecting pipe 33 is provided with several sets of connecting grooves that connect to the heat-insulating connecting blocks 34. The upper end face of the heat-insulating connecting block 34 is aligned with the top end of the heat-insulating protective rod 32. The second drive structure 30 is a dual-axis motor, and the two output shafts of the dual-axis motor are configured not to start at the same time. The outer wall of the second drive structure 30 is provided with a connecting ring 35 that is movably connected to the protective frame 31. Several sets of weight-reducing grooves are provided on the connecting ring 35.

[0049] In this embodiment, the second drive structure 30 is controlled to move downward, causing the second drive structure 30 to drive the heat insulation connecting pipe 33 to move downward, so that the heat insulation protective rod 32 is inserted into the heat insulation connecting pipe 33, and the heat insulation connecting block 34 is inserted into the connecting groove, so that the first lead screw transmission device 41 is connected to the output shaft of the second drive structure 30. This allows the second drive structure 30 to be separated from the seed crystal plate 18 when it is not needed, reducing the damage caused by high temperature to the second drive structure 30 and extending the service life of the second drive structure 30.

[0050] The lifting assembly of the present invention also includes several sets of second lead screw transmission devices 36 arranged in a circular array on the protective frame 31 for controlling the lifting of the connecting ring 35, and a reinforcing heat insulation block 37 arranged on the second lead screw transmission device 36 and connected to the connecting ring 35.

[0051] The lifting assembly of the present invention also includes an electric telescopic rod 38 coaxially connected to the second lead screw transmission device 36, a first lifting gear 39 mounted on the upper end of the electric telescopic rod 38, and a second lifting gear 40 detachably mounted on the output shaft of the second drive structure 30 and meshing with several sets of first lifting gears 39.

[0052] In this embodiment, the second drive structure 30 is activated, which drives the second lifting gear 40 to rotate. The second lifting gear 40 drives several sets of first lifting gears 39 to rotate. The first lifting gears 39 drive the electric telescopic rod 38 to rotate. The electric telescopic rod 38 drives the second lead screw transmission device 36 to work. The second lead screw transmission device 36 drives the connecting ring 35 to move through the reinforcing heat insulation block 37. The connecting ring 35 drives the second drive structure 30 to move downward.

[0053] The above embodiments are only used to illustrate the technical methods of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical methods of the present invention without departing from the spirit and scope of the technical methods of the present invention.

Claims

1. A thermal field device for silicon carbide crystal growth, comprising: Vacuum chamber (1) and growth mechanism disposed inside vacuum chamber (1); The growth mechanism includes a base (3) disposed inside the vacuum chamber (1), a crucible body (4) movably disposed above the base (3) for growing silicon crystals, and a crucible support (5). The growth mechanism also includes a seed crystal (7) that is movably disposed inside the crucible body (4) and used for silicon crystal growth, a seed crystal plate (18) connected to the seed crystal (7), and a lifting assembly for controlling the seed crystal plate to move up and down. The growth mechanism also includes a rigid support member (8) rotatably mounted on the base (3) and rigidly connected to the crucible body (4), a fixing ring (9) mounted on the outside of the rigid support member (8) and connected to the crucible support (5), and several sets of flexible support structures (10) arranged in a circular array on the fixing ring (9) and flexibly connected. The flexible support structure (10) includes a support rod (11) that is vertically fixed to the fixed ring (9), a support arm (12) that is rotatably connected to the support rod (11), and a support seat (13) that is set on the base (3) and elastically connected to the support arm (12). The support base (13) is provided with an elastic component that is connected to the support arm (12); The elastic component includes several sets of guide rods (14) symmetrically arranged inside the support base (13), two sets of guide blocks (15) movably arranged on the guide rods (14), and several sets of first buffer springs (16) sleeved on the guide rods (14) and respectively connected to the guide blocks (15) and the support base (13).

2. The silicon carbide crystal growth thermal field device according to claim 1, characterized in that, The support rod (11) is provided with a vibration damping component to prevent fatigue fracture caused by resonance in the flexible support structure (10); The growth mechanism also includes a rotating component mounted on the base (3) and controlling the rotation of the crucible body (4) and the crucible support (5).

3. The silicon carbide crystal growth thermal field device according to claim 2, characterized in that, The rotating assembly includes a rotating block (19) rotatably mounted on the base (3) and connected to the bottom end of the rigid support (8) and a rotating ring (20) disposed outside the rotating block (19) and connected to the flexible support structure (10). The rotating assembly also includes a main gear (21) rotatably mounted on the base (3) and connected to the rotating block (19), several sets of driven gears (22) respectively meshing with the main gear (21) and rotatably mounted on the lower end face of the rotating ring (20), and a transmission gear ring (23) mounted on the outside of the driven gear (22) and meshing with the driven gear (22).

4. The silicon carbide crystal growth thermal field device according to claim 3, characterized in that, The vibration damping assembly includes a damping plate (25) disposed on a support rod (11) and a multi-layer corrugated connecting pipe (26) disposed between two sets of damping plates (25) and adjustable in distance between the two sets of damping plates (25). The vibration damping assembly also includes several sets of electric lifting structures (27) vertically arranged between the two sets of vibration damping plates (25) and a second buffer spring (28) sleeved on the outside of the electric lifting structure (27) and connected to the two sets of vibration damping plates (25) respectively.

5. The silicon carbide crystal growth thermal field device according to claim 3, characterized in that, The growth mechanism also includes a crucible cover (6) disposed on the upper end of the crucible body (4) and sealed to the crucible body (4), and an induction heating structure (2) disposed outside the vacuum chamber (1) and heating the crucible body (4) and the crucible support (5).

6. The silicon carbide crystal growth thermal field device according to claim 5, characterized in that, The lifting assembly includes a first lead screw drive device (41) detachably disposed on the bottom end face of the crucible cover (6), a protective tube (42) connected to the first lead screw drive device (41), and a transmission structure (29) disposed on the outside of the crucible cover (6) and controlling the first lead screw drive device (41) to work. The lifting assembly also includes a second drive structure (30) for fixing the transmission structure (29) and a protective frame (31) disposed on the outside of the crucible cover (6) and for heat insulation protection of the second drive structure (30).

7. The silicon carbide crystal growth thermal field device according to claim 6, characterized in that, The transmission structure (29) includes a heat-insulating protective rod (32) set on the first lead screw transmission device (41) and passing through the crucible cover (6), a heat-insulating connecting pipe (33) detachably installed on the output shaft of the second drive structure (30), and several sets of heat-insulating connecting blocks (34) set on the outer wall of the heat-insulating protective rod (32) and connected to the heat-insulating connecting pipe (33). The upper end face of the heat insulation connecting block (34) is aligned with the top end of the heat insulation protective rod (32); The outer wall of the second drive structure (30) is provided with a connecting ring (35) that is movably connected to the protective frame (31).

8. The silicon carbide crystal growth thermal field device according to claim 7, characterized in that, The lifting assembly also includes several sets of second lead screw transmission devices (36) arranged in a circular array on the protective frame (31) for controlling the lifting of the connecting ring (35) and a reinforcing heat insulation block (37) arranged on the second lead screw transmission device (36) and connected to the connecting ring (35).

9. The silicon carbide crystal growth thermal field device according to claim 8, characterized in that, The lifting assembly also includes an electric telescopic rod (38) coaxially connected to the second lead screw drive (36), a first lifting gear (39) mounted on the upper end of the electric telescopic rod (38), and a second lifting gear (40) detachably mounted on the output shaft of the second drive structure (30) and meshing with several sets of first lifting gears (39).

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