Thermal field adjusting method for liquid phase method silicon carbide crystal growth

Abstract

The invention relates to the technical field of semiconductors, and particularly discloses a thermal field adjusting method for liquid phase method silicon carbide crystal growth, which comprises the following steps: S1, designing a thermal field structure, and obtaining process parameters related to the quality of a silicon carbide crystal; s2, constructing a crystal quality evaluation standard according to the finally obtained growth characteristics of the silicon carbide crystal; s3, according to the obtained technological parameters related to the quality of the silicon carbide crystals, corresponding permutation, combination and grouping contrast tests are carried out, and after different technological parameter combinations are obtained, a plurality of sets of silicon carbide crystals are prepared; and S4, evaluating the quality of each group of silicon carbide crystals according to the constructed crystal quality evaluation standard, obtaining process parameters of the group where the silicon carbide crystals with the optimal quality are located, and adjusting the thermal field according to the process parameters of the group. The growth process of the silicon carbide single crystal is carried out under the optimal condition, the growth process of the silicon carbide single crystal is remarkably improved, the growth quality of the crystal can be improved, and the growth speed is increased.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a thermal field regulating method for silicon carbide crystal growth using a liquid phase method. Background Art

[0002] Silicon carbide (SiC), a third-generation semiconductor material, boasts excellent properties such as high thermal conductivity, high power output, high-temperature resistance, and radiation resistance. It is primarily used in smart grids, electric vehicles, high-speed trains, advanced radar, and other fields, and is a key material prioritized for development in various countries. A novel liquid-phase SiC single crystal growth technique overcomes the high dislocation density of SiC substrates grown using the traditional vapor-phase method (PVT), resulting in higher-quality SiC single crystal substrates. Research on liquid-phase SiC single crystal growth technology is currently a hot topic.

[0003] Under the current technological system, the growth process of SiC single crystals faces significant quality bottlenecks, most notably excessive residual solvent impurities and frequent microcracks within the crystals. The root cause lies in the imperfect design and control mechanisms of thermal field parameters, which are the core factors hindering the improvement of crystal quality. The liquid phase method for the production of SiC single crystals places stringent requirements on the thermal field environment: maintaining a specific axial temperature gradient while minimizing radial temperature differences, ensuring uniform circumferential temperature distribution, and flexible adjustability of the axial temperature zone. Therefore, a precisely controllable thermal field environment is crucial for achieving high-quality crystal growth. However, existing thermal field structures generally only focus on the structure and materials of the thermal field to obtain higher-quality SiC single crystals, with less attention paid to the parameters of the thermal field structure. Even when attention is paid, it is only to the thermal field temperature. However, focusing solely on the thermal field temperature has limited effect on further improving the quality of SiC single crystals. If the quality of SiC single crystals is to be further improved, it is necessary to obtain thermal field parameters that are more influential on the quality of SiC single crystals, so as to better regulate the thermal field and obtain higher-quality SiC single crystals. Summary of the Invention

[0004] The object of the present invention is to provide a thermal field regulation method for liquid phase silicon carbide crystal growth, which ensures small radial temperature difference, uniform circumferential temperature and easy adjustment of axial temperature difference.

[0005] The present invention is achieved through the following technical solution: A thermal field regulation method for liquid phase silicon carbide crystal growth comprises the following steps: Step S1: designing a thermal field structure to obtain process parameters related to silicon carbide crystal quality; Step S2: constructing a crystal quality evaluation standard based on the growth characteristics of the finally obtained silicon carbide crystal; Step S3: performing corresponding permutation and combination group comparison tests based on the obtained process parameters related to the quality of the silicon carbide crystals, and obtaining several groups of silicon carbide crystals after obtaining different process parameter combinations; Step S4: Evaluate the quality of each group of silicon carbide crystals according to the constructed crystal quality evaluation standard, obtain the process parameters of the group of silicon carbide crystals with the best quality, and adjust the thermal field based on the process parameters of the group.

[0006] The working principle of this technical solution is to obtain more process parameters related to the quality of silicon carbide crystals by designing the thermal field structure, establish corresponding crystal quality evaluation standards, and group and screen the optimal process parameters, so as to adjust the thermal field structure and prepare the best quality silicon carbide crystals through the optimal process parameters. In order to better implement the method of the present invention, further, in step S1, the designed thermal field structure includes: The crucible inside is used for crystal growth, and the heat preservation and position limiting heating part outside is used to heat the crucible and keep it warm and limit the position; The heat preservation and limiting heating part is wrapped with a heating tube from the inside to the outside, a quartz tube is embedded on the outside of the heating tube, the inside of the quartz tube is filled with heat-insulating graphite felt covering the heating tube, and an induction coil is arranged around the outside of the quartz tube; the crucible is placed in the heating tube, and the crucible does not contact the inner wall of the heating tube; The crucible is provided with a lifting device capable of driving the crucible to move up and down in the heating tube; The heat-insulating and position-limiting heating portion is provided with a rotating device capable of driving the heat-insulating and position-limiting heating portion to rotate; the crucible does not rotate along with the rotation of the heat-insulating and position-limiting heating portion.

[0007] The thermal insulation graphite felt can be soft felt or hard felt.

[0008] In order to better implement the method of the present invention, further, in step S1, based on the designed thermal field structure, the process parameters related to the quality of silicon carbide crystals are obtained, including: the rotation speed n of the heat preservation limiting heating part, and the distance d between the bottom of the crucible and the inner wall of the bottom of the heating tube.

[0009] In order to better implement the method of the present invention, further, in step S4, the process parameters of the group of silicon carbide crystals with the best quality are: The speed n of the heat preservation limit heating part is 10rpm~100rpm; The distance d between the bottom of the crucible and the inner wall of the bottom of the heating tube is 8mm~12mm.

[0010] In order to better implement the method of the present invention, further, in step S4, the process parameters of the group of silicon carbide crystals with the best quality are: The speed n of the heat preservation limit heating part is 45 rpm; The distance d between the bottom of the crucible and the inner wall of the bottom of the heating tube is 10 mm.

[0011] In order to better implement the method of the present invention, further, the lifting device includes a lifting shaft, the top of the lifting shaft abuts against the center of the bottom of the crucible, and the lower part of the lifting shaft is provided with a first driving mechanism for driving the lifting shaft to lift the crucible; The rotating device includes a base, a rotating shaft is fixedly connected to the center of the lower part of the base, the top of the rotating shaft is fixedly connected to the base, a second driving mechanism is provided at the lower part of the rotating shaft to drive the rotating shaft to rotate the base, and a heat preservation limit heating part is fixedly installed on the upper part of the base; The lifting shaft is nested in the rotating shaft, and the lifting shaft and the rotating shaft are coaxially arranged. The outer wall of the lifting shaft has no contact with the inner wall of the rotating shaft. The top of the lifting shaft passes through the base and abuts against the bottom center of the crucible in the heat preservation and limiting heating part.

[0012] In order to better implement the method of the present invention, further, a thermocouple for measuring the temperature of the bottom of the crucible is installed in the lifting shaft, and an infrared thermometer for measuring the temperature of the melt or seed crystal in the crucible is also provided on the upper part of the heat-insulating limit heating part.

[0013] In order to better implement the method of the present invention, further, in the step S3, a co-solvent needs to be added during the process of preparing each group of silicon carbide crystals, and the co-solvent is Si a Cr b X c Y d , wherein X is one of the rare earth elements Ce, Nd, and Pr; Y is at least one of the transition metal elements or Al, and 0.3≤a≤0.55, 0.4≤b≤0.6, 0≤c≤0.2, 0≤d≤0.15, and abcd satisfies a+b+c+d=1.

[0014] In order to better implement the method of the present invention, further, in step S1, the process parameters related to the quality of the silicon carbide crystal also include the seeding temperature T1 and the highest temperature T2 during the entire growth process, and the pulling speed V during the growth of the silicon carbide crystal; The seeding temperature T1 is 1820° C. to 1880° C., the highest temperature T2 during the entire growth process is 1900° C. to 1980° C., and the pulling speed V during the growth of the silicon carbide crystal is 0.005 mm / h to 0.5 mm / h.

[0015] In order to better implement the method of the present invention, further, in step S2, the specific process of constructing the crystal quality evaluation standard is as follows: the growth characteristics of the finally obtained silicon carbide crystal are divided into several levels, and corresponding crystal quality evaluation values ​​are given according to the different levels; Crystal quality assessment values ​​include: 0~40, 40~60, 60~70, 70~85, 85~100; The corresponding growth characteristics of the silicon carbide crystal are: The solvent inclusion is serious, the grooves are deep and numerous, the step clustering is serious, and the hexagonal characteristics are not obvious; There is severe step bunching, many grooves, and unclear hexagonal features; The step bunching is serious and the hexagonal features are not obvious; The hexagonal features are obvious and the surface is smooth; Obvious hexagonal features, smooth surface, no solvent wrapping, and no cracks.

[0016] Compared with the prior art, the present invention has the following advantages and beneficial effects: (1) The present invention obtains more process parameters related to the quality of silicon carbide crystals by optimizing the structure of the thermal field. By establishing corresponding crystal quality evaluation standards, the optimal process parameters are screened, thereby adjusting the thermal field structure and preparing silicon carbide crystals with the best quality through the optimal process parameters. (2) The thermal field structure designed in the present invention allows the crucible to be simply raised and lowered, and only the external heat-insulating limiting heating part is rotated. In this way, even if an error occurs between the crucible and the heat-insulating limiting heating part during the heat-insulating assembling process, causing the heat-insulating limiting heating part and the crucible to be misaligned, the consistency in the diameter direction and the circumference direction can be achieved through rotation, thereby ensuring the radial symmetry of the crucible's thermal field, having a corrective effect on the asymmetry caused by the heat-insulating processing and assembly, improving the radial temperature difference of the crucible's thermal field, ensuring that the heat-insulating limiting heating part uniformly heats and insulates the crucible, and thereby improving the quality of the silicon carbide growth crystal; (3) The present invention adjusts the thermal field by obtaining the optimal process parameters, so that the growth process of silicon carbide single crystal is carried out under the optimal conditions. It has a significant improvement effect on the growth process of silicon carbide single crystal, can improve the growth quality of the crystal, increase the growth rate, and make the temperature distribution more uniform, reduce crystal cracking, and help solution wrapping, effectively reducing defects in the crystal growth process. It has broad application prospects, especially in the industrial production of silicon carbide materials, providing technical support for high-quality and long-term growth of silicon carbide, which can further promote the commercial application of silicon carbide. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings: Figure 1 It is a schematic cross-sectional view of the thermal field structure of the present invention.

[0018] Among them: 1 - crucible, 2 - heat preservation and limiting heating part, 21 - heating tube, 22 - quartz tube, 23 - heat preservation graphite felt, 24 - coil, 3 - lifting device, 31 - lifting shaft, 32 - first driving mechanism, 4 - rotating device, 41 - base, 42 - rotating shaft, 43 - second driving mechanism, 5 - thermocouple, 6 - infrared thermometer. DETAILED DESCRIPTION

[0019] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0020] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0021] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0022] Example 1: This embodiment provides a thermal field adjustment method for liquid phase silicon carbide crystal growth, comprising the following steps: Step S1: designing a thermal field structure to obtain process parameters related to silicon carbide crystal quality; The designed thermal field structure, such as Figure 1 As shown, including: A crucible 1 for crystal growth inside and a heat-insulating and limiting heating portion 2 for heating the crucible 1 and keeping the crucible 1 warm outside; The heat-insulating and position-limiting heating portion 2 is enclosed by a heating tube 21 from the inside to the outside. A quartz tube 22 is embedded in the outside of the heating tube 21. The inside of the quartz tube 22 is filled with a heat-insulating graphite felt 23 that covers the heating tube 21. An induction coil 24 is arranged around the outside of the quartz tube 22. The crucible 1 is placed in the heating tube 21, and the crucible 1 does not contact the inner wall of the heating tube 21. The crucible 1 is provided with a lifting device 3 capable of driving the crucible 1 to move up and down in the heating tube 21; The heat preservation and limiting heating part 2 is provided with a rotating device 4 capable of driving the heat preservation and limiting heating part 2 to rotate; the crucible 1 does not rotate along with the rotation of the heat preservation and limiting heating part 2; The structure of the heat field is designed in this way mainly to obtain the two key parameters: the rotation speed n of the heat preservation and limiting heating part 2 and the distance d between the bottom of the crucible 1 and the inner wall of the bottom of the heating tube 21; Step S2: Based on the growth characteristics of the finally obtained silicon carbide crystal, a crystal quality evaluation standard is constructed; the constructed crystal quality evaluation standard is shown in Table 1: Table 1 Crystal quality evaluation standards Step S3: Based on the obtained process parameters related to the quality of silicon carbide crystals, corresponding permutation and combination grouping comparison tests are performed to obtain different process parameter combinations and obtain several groups of silicon carbide crystals; the specific grouping is shown in Table 2. Table 2 Grouping of the two sets of process parameters after permutation and combination Step S4: Evaluate the quality of each group of silicon carbide crystals according to the constructed crystal quality evaluation standard, obtain the process parameters of the group of silicon carbide crystals with the best quality, and adjust the thermal field based on the process parameters of the group.

[0023] The specific experimental process is as follows: the levels of n are 0 rpm, 30 rpm, 60 rpm, 100 rpm, and 130 rpm, and the levels of d1 are 0 mm, 5 mm, 10 mm, 15 mm, and 20 mm. A cosolvent is added during the preparation of each group of silicon carbide crystals. The cosolvent is Si a Cr b X c Y d , wherein X is one of the rare earth elements Ce, Nd, and Pr; Y is at least one of the transition metal elements or Al, and 0.3≤a≤0.55, 0.4≤b≤0.6, 0≤c≤0.2, 0≤d≤0.15, and abcd satisfies a+b+c+d=1.

[0024] The experimental results are shown in Table 3. Table 3 The quality of silicon carbide crystals obtained in each group The crystal quality evaluation value is determined based on the characteristics of the high-quality silicon carbide single crystal described above in this patent.

[0025] According to Table 2, the silicon carbide crystals obtained in Group 11 were of the best quality. Therefore, the thermal field was adjusted to set the rotation speed n of the heat-insulating and limiting heating unit 2 to 45 rpm and the distance d between the bottom of the crucible 1 and the bottom inner wall of the heating tube 21 to 10 mm.

[0026] Example 2: On the basis of the above embodiment, this embodiment also conducts group experiments on the seeding temperature T1, the highest temperature T2 during the entire growth process, and the pulling speed V during the growth of the silicon carbide crystal based on the above-mentioned optimal process parameters, and sets the characteristics of the silicon carbide single crystal finally obtained. The experimental process is the same as above and will not be repeated here. In addition, since the above three process parameters have a significant impact on the silicon carbide single crystal, only the optimal range values ​​of the above three process parameters can be obtained, specifically the seeding temperature T1 is 1820℃~1880℃, the highest temperature T2 during the entire growth process is 1900℃~1980℃, and the pulling speed V during the growth of the silicon carbide crystal is 0.005mm / h~0.5mm / h. The other parts of this embodiment are the same as the above embodiment and will not be repeated here.

[0027] Example 3: Based on the above embodiments, this embodiment further defines the structure of the thermal field, such as Figure 1 As shown, the lifting device 3 includes a lifting shaft 31, the top of the lifting shaft 31 abuts against the center of the bottom of the crucible 1, and the lower part of the lifting shaft 31 is provided with a first driving mechanism 32 that drives the lifting shaft 31 to lift the crucible 1; The rotating device 4 includes a base 41, a rotating shaft 42 is fixedly connected to the center of the lower portion of the base 41, the top of the rotating shaft 42 is fixedly connected to the base 41, and a second driving mechanism 43 is provided at the lower portion of the rotating shaft 42 to drive the rotating shaft 42 to rotate the base 41. The heat preservation limit heating part 2 is fixedly installed on the upper portion of the base 41; The lifting shaft 31 is nested in the rotating shaft 42, and the lifting shaft 31 and the rotating shaft 42 are coaxially arranged. The outer wall of the lifting shaft 31 has no contact with the inner wall of the rotating shaft 42. The top of the lifting shaft 31 passes through the base 1 and abuts against the bottom center of the crucible 1 in the heat preservation and limiting heating part 2.

[0028] The lifting shaft 31 and the first driving mechanism 32 in the lifting device 3, and the second driving mechanism 43 and the rotating shaft 42 in the rotating device 4 are the same as the lifting mechanism and the rotating mechanism in the invention patent with application number 202110550421.1, and their implementation principles are common technical knowledge known in the art. Figure 1 The lifting device 3 and the rotating device 4 are schematic diagrams. Since they are prior art, their specific driving structures are not described and refined in detail. The rest of this embodiment is the same as the above embodiment and will not be repeated here.

[0029] Example 4: Based on the above embodiments, this embodiment further defines the structure of the thermal field, such as Figure 1 As shown, a thermocouple 5 for measuring the bottom temperature of the crucible 1 is also installed within the lifting shaft 31. An infrared thermometer 6 for measuring the temperature of the melt or seed crystal within the crucible 1 is also installed above the heat-insulating, position-limiting heating unit 2. The infrared thermometer 6 is used to measure the melt temperature or seed crystal temperature, while the thermocouple 5 is used to measure the bottom temperature of the crucible 1. It is worth noting that in order to measure the bottom temperature of the crucible 1 in real time, the thermocouple 5 must be raised and lowered synchronously with the crucible 1 via the lifting shaft 31. The remaining parts of this embodiment are the same as those of the above-described embodiment and will not be further described.

[0030] It is understandable that the working principles and working processes of the thermal field structure according to an embodiment of the present invention, such as the heating tube 21 and the coil 24, are prior art and well known to those skilled in the art, and will not be described in detail here.

[0031] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. A thermal field regulation method for liquid phase silicon carbide crystal growth, characterized in that: The following steps are involved: Step S1: designing a thermal field structure to obtain process parameters related to silicon carbide crystal quality; Step S2: constructing a crystal quality evaluation standard based on the growth characteristics of the finally obtained silicon carbide crystal; Step S3: performing corresponding permutation and combination group comparison tests based on the obtained process parameters related to the quality of the silicon carbide crystals, and obtaining several groups of silicon carbide crystals after obtaining different process parameter combinations; Step S4: Evaluate the quality of each group of silicon carbide crystals according to the constructed crystal quality evaluation standard, obtain the process parameters of the group of silicon carbide crystals with the best quality, and adjust the thermal field based on the process parameters of the group.

2. The thermal field regulation method for liquid phase silicon carbide crystal growth according to claim 1, characterized in that: In step S1, the designed thermal field structure includes: A crucible (1) for crystal growth inside, and a heat-insulating and position-limiting heating portion (2) for heating the crucible (1) and performing heat preservation and position limiting on the crucible (1) outside; The heat preservation and limiting heating portion (2) is enclosed by a heating tube (21) from the inside to the outside, a quartz tube (22) is embedded on the outside of the heating tube (21), the quartz tube (22) is filled with heat-insulating graphite felt (23) that encloses the heating tube (21), and an induction coil (24) is arranged around the outside of the quartz tube (22); the crucible (1) is placed in the heating tube (21), and the crucible (1) does not contact the inner wall of the heating tube (21); The crucible (1) is provided with a lifting device (3) capable of driving the crucible (1) to move up and down in the heating tube (21); The heat-insulating position-limiting heating portion (2) is provided with a rotating device (4) capable of driving the heat-insulating position-limiting heating portion (2) to rotate; the crucible (1) does not rotate along with the rotation of the heat-insulating position-limiting heating portion (2).

3. The thermal field regulation method for liquid phase silicon carbide crystal growth according to claim 2, characterized in that: In step S1, based on the designed thermal field structure, process parameters related to the quality of the silicon carbide crystal are obtained, including: the rotation speed n of the heat preservation and limiting heating part (2), and the distance d between the bottom of the crucible (1) and the inner wall of the bottom of the heating tube (21).

4. The thermal field regulation method for liquid phase silicon carbide crystal growth according to claim 3, characterized in that: In step S4, the process parameters of the group of silicon carbide crystals with the best quality are: The rotation speed n of the heat preservation limiting heating part (2) is 10 rpm-100 rpm; The distance d between the bottom of the crucible (1) and the inner wall of the bottom of the heating tube (21) is 8 mm to 12 mm.

5. The thermal field adjustment method for liquid phase silicon carbide crystal growth according to claim 4, characterized in that: In step S4, the process parameters of the group of silicon carbide crystals with the best quality are: The rotation speed n of the heat preservation limit heating part (2) is 45 rpm; The distance d between the bottom of the crucible (1) and the inner wall of the bottom of the heating tube (21) is 10 mm.

6. The thermal field adjustment method for liquid phase silicon carbide crystal growth according to any one of claims 2 to 5, characterized in that: The lifting device (3) comprises a lifting shaft (31), the top of the lifting shaft (31) abuts against the center of the bottom of the crucible (1), and a first driving mechanism (32) is provided at the bottom of the lifting shaft (31) for driving the lifting shaft (31) to lift the crucible (1); The rotating device (4) includes a base (41), a rotating shaft (42) is fixedly connected to the center of the lower portion of the base (41), the top of the rotating shaft (42) is fixedly connected to the base (41), a second driving mechanism (43) is provided at the lower portion of the rotating shaft (42) for driving the rotating shaft (42) to rotate the base (41), and a heat-insulating limit heating portion (2) is fixedly installed at the upper portion of the base (41); The lifting shaft (31) is nested in the rotating shaft (42), and the lifting shaft (31) and the rotating shaft (42) are coaxially arranged, the outer wall of the lifting shaft (31) and the inner wall of the rotating shaft (42) are not in contact, and the top of the lifting shaft (31) passes through the base (1) and abuts against the bottom center of the crucible (1) in the heat-insulating limit heating part (2).

7. The thermal field adjustment method for liquid phase silicon carbide crystal growth according to claim 6, characterized in that: A thermocouple (5) for measuring the bottom temperature of the crucible (1) is also installed in the lifting shaft (31), and an infrared thermometer (6) for measuring the temperature of the melt or seed crystal in the crucible (1) is also provided on the upper part of the heat-insulating limit heating portion (2).

8. The thermal field adjustment method for liquid phase silicon carbide crystal growth according to any one of claims 1 to 5, characterized in that: In the step S3, a co-solvent is added during the preparation of each group of silicon carbide crystals. The co-solvent is Si a Cr b X c Y d , wherein X is one of the rare earth elements Ce, Nd, and Pr; Y is at least one of the transition metal elements or Al, and 0.3≤a≤0.55, 0.4≤b≤0.6, 0≤c≤0.2, 0≤d≤0.15, and abcd satisfies a+b+c+d=1.

9. The thermal field adjustment method for liquid phase silicon carbide crystal growth according to any one of claims 1 to 5, characterized in that: In step S1, the process parameters related to the quality of the silicon carbide crystal also include the seeding temperature T1 and the highest temperature T2 during the entire growth process, as well as the pulling speed V during the growth of the silicon carbide crystal; The seeding temperature T1 is 1820° C. to 1880° C., the highest temperature T2 during the entire growth process is 1900° C. to 1980° C., and the pulling speed V during the growth of the silicon carbide crystal is 0.005 mm / h to 0.5 mm / h.

10. The thermal field adjustment method for liquid phase silicon carbide crystal growth according to any one of claims 1 to 5, characterized in that: In step S2, the specific process of constructing the crystal quality evaluation standard is as follows: the growth characteristics of the finally obtained silicon carbide crystal are divided into several levels, and corresponding crystal quality evaluation values ​​are given according to the different levels; Crystal quality assessment values ​​include: 0~40, 40~60, 60~70, 70~85, 85~100; The corresponding growth characteristics of the silicon carbide crystal are: The solvent inclusion is serious, the grooves are deep and numerous, the step clustering is serious, and the hexagonal characteristics are not obvious; There is severe step bunching, many grooves, and unclear hexagonal features; The step bunching is serious and the hexagonal features are not obvious; The hexagonal features are obvious and the surface is smooth; Obvious hexagonal features, smooth surface, no solvent wrapping, and no cracks.

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