A silicon carbide single crystal growth apparatus

Abstract

This invention discloses a silicon carbide single crystal growth apparatus, including a crucible for loading silicon carbide raw material and a flow guide disposed inside the crucible. The upper surface of the crucible is used to fix a seed crystal. After the silicon carbide raw material is loaded into the crucible, the lower end of the flow guide is lower than the upper surface of the silicon carbide raw material in the crucible, dividing the silicon carbide raw material into multiple regions. The upper end of the flow guide is higher than the upper surface of the silicon carbide raw material in the crucible. After the silicon carbide raw material in the multiple regions sublimates into a gaseous phase, it moves upward under the guidance of the flow guide and contacts the seed crystal. The silicon carbide single crystal growth apparatus provided by this invention, by setting a flow guide inside the crucible, uniformly guides the sublimated gaseous silicon carbide raw material to the seed crystal at the top of the crucible, so that the gaseous silicon carbide raw material is uniformly deposited on the seed crystal growth plane, thereby obtaining a silicon carbide single crystal of uniform quality.

Description

Technical Field

[0001] This invention relates to the field of silicon carbide single crystal manufacturing equipment technology, and particularly to a silicon carbide single crystal growth apparatus. Background Technology

[0002] Currently, in existing technologies for growing silicon carbide single crystals using the physical vapor transport (PVT) method, the material is typically loaded at the bottom and a seed crystal is placed at the top. The SiC (silicon carbide) raw material is the relatively hot end, and the seed crystal is the relatively cold end. The SiC raw material is vaporized at a high temperature above 2000℃ into gases such as Si, Si2C, SiC, and SiC2. Under the influence of an inert gas flow such as argon, these gases migrate to the surface of the seed crystal and form bonds with the atoms on the seed crystal surface, thereby achieving the growth of a new crystal.

[0003] In the process of growing silicon carbide single crystals using this method, because the heater is located on the periphery of the crucible, the temperature at the crucible edge is higher than that at the center. Typically, the raw material at the crucible edge preferentially vaporizes, and the gas migrates from the high temperature to the low temperature direction. That is, the gas starts from the edge and gathers towards the center, then migrates upwards at the center, causing the raw material to preferentially deposit at the center of the seed crystal before expanding outwards, thus growing a crystal of a predetermined size. However, as the crystal size increases, the distance between the edge and center of the seed crystal increases, resulting in a greater temperature difference between them. Simultaneously, the distance between the raw material edge and center also increases. On the one hand, the utilization rate of the raw material at the center of the crucible is greatly reduced; on the other hand, the quality difference between the central and edge regions of the newly grown crystal is significant, leading to uneven crystal quality and greatly increased stress, which is detrimental to the growth of larger crystals, such as those 8 inches and above.

[0004] Therefore, how to provide a silicon carbide single crystal growth device that produces uniform silicon carbide single crystals and thus obtains larger-sized silicon carbide single crystals is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] In view of this, the object of the present invention is to provide a silicon carbide single crystal growth apparatus to obtain silicon carbide single crystals with uniform quality.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A silicon carbide single crystal growth apparatus includes a crucible for loading silicon carbide raw materials and a flow guide disposed inside the crucible.

[0008] The top of the crucible is used to fix the seed crystal;

[0009] After the crucible is loaded with silicon carbide raw material, the lower end of the guide section is lower than the upper surface of the silicon carbide raw material in the crucible, which is used to divide the silicon carbide raw material into multiple regions;

[0010] The upper end of the flow guide is higher than the upper surface of the silicon carbide raw material in the crucible. After the silicon carbide raw material in multiple regions sublimates into the gas phase, it moves upward under the guidance of the flow guide and contacts the seed crystal.

[0011] Preferably, in the above-mentioned silicon carbide single crystal growth apparatus, the flow guide is configured as a vertically arranged single-layer cylinder.

[0012] Preferably, in the above-mentioned silicon carbide single crystal growth apparatus, the flow guide is concentrically arranged with the crucible, and the flow guide passes through the radius center of the crucible.

[0013] Optionally, in the above-mentioned silicon carbide single crystal growth apparatus, the configuration of the flow guide is a vertically arranged multi-layer concentric cylinder.

[0014] Preferably, in the above-mentioned silicon carbide single crystal growth apparatus, the flow guide is concentrically arranged with the crucible, and the flow guide passes uniformly through the bisector of the radius of the crucible.

[0015] Preferably, in the above-mentioned silicon carbide single crystal growth apparatus, the vertical distance between the lower end of the guide section and the upper surface of the silicon carbide raw material in the crucible is a first preset distance; the range of the first preset distance is 1 / 3 to 1 / 2 of the height of the silicon carbide raw material.

[0016] Optionally, in the above-described silicon carbide single crystal growth apparatus, the lower end of the flow guide is in contact with the bottom of the crucible.

[0017] Preferably, in the above-mentioned silicon carbide single crystal growth apparatus, the vertical distance between the upper end of the guide section and the seed crystal is a second preset distance; the range of the second preset distance is 15-100mm.

[0018] Preferably, in the above-mentioned silicon carbide single crystal growth apparatus, the material of the flow guide is graphite with an impurity content of less than 50 ppm.

[0019] Optionally, in the above-mentioned silicon carbide single crystal growth apparatus, the material of the flow guide is graphite with an impurity content of less than 5 ppm.

[0020] Preferably, in the above-mentioned silicon carbide single crystal growth apparatus, the material of the flow guide is one or more of tungsten, rhenium, osmium, niobium, molybdenum, iridium and tantalum with a purity greater than 99.9%.

[0021] Optionally, in the above-mentioned silicon carbide single crystal growth apparatus, the material of the flow guide is one or more of tungsten, rhenium, osmium, niobium, molybdenum, iridium and tantalum with a purity greater than 99.99%.

[0022] Optionally, in the above-mentioned silicon carbide single crystal growth apparatus, the material of the guide section is one or more of tungsten carbide, rhenium carbide, osmium carbide, niobium carbide, molybdenum carbide, iridium carbide and tantalum carbide with a purity greater than 99.9%.

[0023] Optionally, in the above-mentioned silicon carbide single crystal growth apparatus, the material of the guide section is one or more of tungsten carbide, rhenium carbide, osmium carbide, niobium carbide, molybdenum carbide, iridium carbide and tantalum carbide with a purity greater than 99.99%.

[0024] Optionally, in the above-mentioned silicon carbide single crystal growth apparatus, the material of the guide section is graphite with one or more coatings of tungsten, rhenium, osmium, niobium, molybdenum, iridium and tantalum with a purity greater than 99.99%.

[0025] As can be seen from the above technical solution, the silicon carbide single crystal growth apparatus provided by the present invention differs from the prior art in that a flow guide is provided inside the crucible. During the growth of silicon carbide single crystals using the apparatus provided by the present invention, the lower end of the flow guide is lower than the upper surface of the silicon carbide raw material in the crucible, dividing the silicon carbide raw material in the crucible into multiple regions. Simultaneously, the upper end of the flow guide is higher than the upper surface of the silicon carbide raw material in the crucible. After the silicon carbide raw material in multiple regions sublimates into a gaseous phase, due to the presence of the flow guide, the gaseous silicon carbide raw material will not preferentially deposit at the center of the seed crystal along the direction from high temperature to low temperature, as in the prior art. Instead, under the action of the flow guide, it will uniformly contact the seed crystal and uniformly deposit on the surface of the seed crystal, thereby resulting in a uniform quality of the grown silicon carbide single crystal. Compared with the prior art, the silicon carbide single crystal growth apparatus provided by the present invention produces silicon carbide single crystals with smaller quality differences between the center and edge, and uniform stress distribution, enabling the growth of silicon carbide single crystals of 8 inches and above. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 A cross-sectional view of a specific embodiment of the silicon carbide single crystal growth apparatus provided by the present invention;

[0028] Figure 2A top view of a specific embodiment of the silicon carbide single crystal growth apparatus provided by the present invention;

[0029] Figure 3 A cross-sectional view of another specific embodiment of the silicon carbide single crystal growth apparatus provided by the present invention;

[0030] Figure 4 A top view of another specific embodiment of the silicon carbide single crystal growth apparatus provided by the present invention;

[0031] Among them, 10 is the crucible, 20 is the flow guide, and 30 is the seed crystal. Detailed Implementation

[0032] The core of this invention is to provide a silicon carbide single crystal growth apparatus to obtain silicon carbide single crystals with uniform quality. For specific details, please see the specific implementation method below.

[0033] To enable those skilled in the art to better understand the present invention, embodiments of the present invention will be described below with reference to the accompanying drawings. Furthermore, the embodiments shown below do not limit the scope of the invention as described in the claims. Additionally, the complete content of the configurations represented in the following embodiments is not limited to those necessary for the solution of the invention as described in the claims.

[0034] See Figure 1 This invention discloses a silicon carbide single crystal growth apparatus, comprising a crucible 10 for loading silicon carbide raw material, with the top of the crucible 10 used to fix a seed crystal 30. The apparatus also includes a flow guide 20 disposed inside the crucible 10. After the crucible 10 is loaded with silicon carbide raw material, the lower end of the flow guide 20 is lower than the upper surface of the silicon carbide raw material, dividing the silicon carbide raw material into multiple regions. Simultaneously, the upper end of the flow guide 20 is higher than the upper surface of the silicon carbide raw material, causing the silicon carbide raw material in the multiple regions to sublimate into a gaseous phase. Under the guidance of the flow guide 20, the gaseous silicon carbide raw material moves upward and contacts the seed crystal 30 at the top of the crucible 10. The gaseous silicon carbide raw material does not accumulate and deposit in the central region of the seed crystal 30 due to the temperature difference between the edge and central regions.

[0035] It should be noted that, since the fumed silicon carbide material will accumulate in the central region of the seed crystal 30 due to the temperature difference, and the silicon carbide material on the side wall of the crucible 10 is more likely to sublimate, the purpose of the guide section 20 is to guide the fumed silicon carbide material near the side wall of the crucible 10 to the edge region of the seed crystal 30, so as to balance the deposition rate of the fumed silicon carbide material in the central region and the edge region of the seed crystal 30, and grow a silicon carbide single crystal with uniform quality.

[0036] The silicon carbide single crystal growth apparatus provided by the present invention has a flow guide 20 inside the crucible 10. During the growth of the silicon carbide single crystal, the flow guide 20 divides the silicon carbide raw material inside the crucible 10 into multiple regions. After the silicon carbide raw material in multiple regions sublimates, the vapor phase silicon carbide raw material is uniformly guided to each region on the surface of the seed crystal 30, so that the vapor phase silicon carbide raw material is uniformly deposited on the surface of the seed crystal 30, thereby making the grown silicon carbide single crystal of uniform quality.

[0037] To further optimize the above technical solution, see [link / reference]. Figure 1 and Figure 2 The flow guide 20 provided in this embodiment of the invention is configured as a vertically arranged single-layer cylinder. The single-layer cylindrical flow guide 20 divides the silicon carbide raw material in the crucible 10 into two regions: the inner region of the flow guide 20 and the outer region between the flow guide 20 and the wall of the crucible 10. During the growth of the silicon carbide single crystal, the silicon carbide raw material in the outer region preferentially sublimates. The gaseous silicon carbide raw material moves vertically upward in the space between the flow guide 20 and the crucible 10. After the horizontal height of the vertically moving gaseous silicon carbide raw material exceeds the flow guide 20, a larger portion of it vertically upward contacts the edge region of the seed crystal 30, and a smaller portion contacts the central region of the seed crystal 30. The silicon carbide raw material in the inner region then sublimates into a gaseous phase and moves vertically upward to the central region of the seed crystal 30, making the deposition rate of the gaseous silicon carbide raw material in the edge region and the central region of the seed crystal 30 similar, resulting in a more uniform radial quality of the silicon carbide single crystal.

[0038] To further optimize the above technical solution, the guide section 20 provided in the embodiment of the present invention is concentrically arranged with the crucible 10, and the diameter of the guide section 20 is half the diameter of the crucible 10, so that the cylindrical guide section 20 passes through the center of the radius of the crucible 10.

[0039] See Figure 3 and Figure 4 In another embodiment of the present invention, the flow guide 20 is configured as a vertically arranged double-layer concentric cylinder. The two-layer cylindrical flow guide 20 divides the silicon carbide raw material in the crucible 10 into three regions. During the growth of the silicon carbide single crystal, the silicon carbide raw material in the three regions sublimates sequentially from the outside to the inside. Compared with the flow guide 20 configured as a single-layer cylinder, the double-layer concentric cylinder flow guide 20 provided in this embodiment provides more layered guidance for the vapor-phase silicon carbide raw material, making the deposition rate of the vapor-phase silicon carbide raw material in the edge region and the center region of the seed crystal 30 closer, and resulting in a more uniform radial quality of the obtained silicon carbide single crystal.

[0040] It should be noted that the configuration of the flow guide 20 can also be three or more concentric cylinders arranged vertically.

[0041] To further optimize the above technical solution, the flow guide 20 provided in this embodiment of the invention is concentrically arranged with the crucible 10, and the two cylindrical layers of the flow guide 20 pass through two trisection points on the radius of the crucible 10.

[0042] It should be noted that the configuration of the guide section 20 can also be a vertically arranged three or more concentric cylinders, which are also concentrically arranged with the crucible 10 and pass evenly through the bisector of the radius of the crucible 10.

[0043] Furthermore, during the growth of silicon carbide single crystals, the vertical distance between the lower end of the guide section 20 and the upper surface of the silicon carbide raw material in the crucible 10 is a first preset distance, which ranges from 1 / 3 to 1 / 2 of the height of the silicon carbide raw material. Setting the first preset distance ensures that the guide section 20 divides the silicon carbide raw material in the crucible into multiple regions at a certain depth, so that during the growth of silicon carbide single crystals, a sufficient amount of gaseous silicon carbide raw material will move to the corresponding position on the seed crystal 30 under the guidance of the guide section 20.

[0044] In another embodiment of the present invention, the lower end of the flow guide 20 contacts the bottom of the crucible 10 to completely divide the silicon carbide raw material in the crucible 10 into multiple regions. The silicon carbide raw materials in the multiple regions are independent of each other. During the growth of silicon carbide single crystal, the silicon carbide raw materials in the multiple regions sublimate and move to the corresponding positions on the seed crystal 30 under the guidance of the flow guide 20.

[0045] To further optimize the above technical solution, the vertical distance between the upper end of the guide portion 20 and the lower plane of the seed crystal 30 provided in this embodiment of the invention is a second preset distance, which ranges from 10 to 200 mm. It should be noted that, preferably, the range of the second preset distance is 15 to 100 mm.

[0046] It should be further noted that, more preferably, the range of the second preset distance is 20-80mm.

[0047] Setting a second preset distance serves two purposes: firstly, it ensures that the guide section 20 directs the fumed silicon carbide material to a sufficient height, allowing it to contact the corresponding position of the seed crystal 30. This prevents the fumed silicon carbide material from being too far from the seed crystal 30 after its horizontal height exceeds the guide section 20, causing it to move towards the center region of the seed crystal 30 under the influence of temperature, resulting in uneven quality of the grown silicon carbide single crystal. Secondly, it prevents the guide section from being too high, causing it to contact the surface of the newly grown crystal in the later stages of crystal growth, thus damaging the quality of the crystal.

[0048] Furthermore, in the embodiments provided by the present invention, the material of the guide portion 20 is graphite with an impurity content of less than 50 ppm.

[0049] In another embodiment provided by the present invention, the guide portion 20 is made of graphite with an impurity content of less than 5 ppm.

[0050] Furthermore, in a specific embodiment of the present invention, the material of the guide portion 20 is a mixture of tungsten, rhenium, osmium, niobium, molybdenum, iridium and tantalum with a purity greater than 99.9%.

[0051] It should be noted that the material of the guide section 20 is preferably a mixture of tungsten, rhenium and osmium with a purity greater than 99.9%, and more preferably tungsten metal with a purity greater than 99.9%.

[0052] Furthermore, in another specific embodiment of the present invention, the material of the guide portion 20 is a mixture of tungsten, rhenium, osmium, niobium, molybdenum, iridium and tantalum with a purity greater than 99.99%.

[0053] It should be noted that the material of the guide section 20 is preferably a mixture of niobium, molybdenum, iridium and tantalum with a purity greater than 99.99%, and more preferably tantalum metal with a purity greater than 99.99%.

[0054] Furthermore, in a specific embodiment of the present invention, the material of the guide portion 20 is a mixture of tungsten carbide, rhenium carbide, osmium carbide, niobium carbide, molybdenum carbide, iridium carbide and tantalum carbide with a purity greater than 99.9%.

[0055] It should be noted that the material of the guide section 20 is preferably a mixture of tungsten carbide, rhenium carbide and osmium carbide with a purity greater than 99.9%, and more preferably tungsten carbide with a purity greater than 99.9%.

[0056] Furthermore, in another specific embodiment of the present invention, the material of the guide portion 20 is a mixture of tungsten carbide, rhenium carbide, osmium carbide, niobium carbide, molybdenum carbide, iridium carbide and tantalum carbide with a purity greater than 99.99%.

[0057] It should be noted that the material of the guide section 20 is preferably a mixture of niobium carbide, molybdenum carbide, iridium carbide and tantalum carbide with a purity greater than 99.99%, and more preferably tantalum carbide with a purity greater than 99.99%.

[0058] Furthermore, in another specific embodiment of the present invention, the guide portion 20 is made of graphite coated with a mixture of tungsten, rhenium, osmium, niobium, molybdenum, iridium and tantalum with a purity greater than 99.99%.

[0059] It should be noted that the material of the guide part 20 is preferably graphite with a coating of a mixture of tungsten, rhenium and osmium with a purity greater than 99.99%, and more preferably graphite with a coating of tungsten metal with a purity greater than 99.99%.

[0060] In one specific embodiment of the present invention, a silicon carbide single crystal with a diameter of 200 mm is grown using the silicon carbide single crystal growth apparatus provided by the present invention. The flow guiding part 20 is a vertically arranged single-layer cylinder, concentrically arranged with the crucible 10, and passes through the radius center of the crucible 10. The lower end of the flow guiding part 20 is located below the upper surface of the silicon carbide raw material, and the vertical distance between the flow guiding part 20 and the upper surface of the silicon carbide raw material is 1 / 2 of the height of the silicon carbide raw material. The vertical distance between the upper end of the flow guiding part 20 and the lower plane of the seed crystal 30 is 25 mm. The guide section 20 is made of a 2mm thick tantalum sheet, and a silicon carbide single crystal with a diameter of 200mm is grown. After growth, the FWHM (full width at half maximum) values ​​at three points on the silicon carbide single crystal are measured to determine the quality inhomogeneity of the silicon carbide single crystal. X-ray rocking curves of the (0001) surface at three points, one at the center of the diameter direction of the silicon carbide single crystal and the other at a distance of 10mm from the edge, are obtained. The FWHM values ​​at the three points are 26.4 arcseconds, 25.2 arcseconds and 27 arcseconds from left to right, with an average value of 26.2 arcseconds. The quality inhomogeneity of the silicon carbide single crystal is 6.9%.

[0061] In another specific embodiment of the present invention, a silicon carbide single crystal with a diameter of 300 mm is grown using the silicon carbide single crystal growth apparatus provided by the present invention. The flow guiding part 20 is a vertically arranged double-layer cylinder, concentrically arranged with the crucible 10, and passes through two trisection points of the radius of the crucible 10. The lower end of the flow guiding part 20 is located below the upper surface of the silicon carbide raw material, and the vertical distance between the flow guiding part 20 and the upper surface of the silicon carbide raw material is 1 / 3 of the height of the silicon carbide raw material. The vertical distance between the upper end of the flow guiding part 20 and the lower plane of the seed crystal 30 is 30 mm. The flow guide 20 is made of a 3mm graphite ring with a purity of 4.5ppm, with a 30µm thick niobium metal outer layer. A silicon carbide single crystal with a diameter of 300mm is grown. After growth, the FWHM values ​​at three points on the silicon carbide single crystal are measured to determine the quality inhomogeneity of the silicon carbide single crystal. X-ray rocking curves of the (0001) surface at three points, one at the center of the diameter direction of the silicon carbide single crystal and one 10mm away from the edge, are obtained. The FWHM values ​​at the three points from left to right are 28 arcseconds, 27 arcseconds, and 26.4 arcseconds, with an average value of 27.1 arcseconds. The quality inhomogeneity of the silicon carbide single crystal is 5.9%.

[0062] Without the guide section 20, a silicon carbide single crystal with a diameter of 200 mm was grown using the existing PVT method. After growth, the FWHM values ​​at three points on the silicon carbide single crystal were measured, and the X-ray rocking curves of the (0001) plane at the center of the diameter direction and 10 mm from the edge of the silicon carbide single crystal were obtained. The FWHM (full width at half maximum) values ​​at the three points from left to right were 39.6 arcseconds, 72 arcseconds, and 64.8 arcseconds, with an average value of 58.8 arcseconds. The radial non-uniformity of the silicon carbide single crystal was found to be 55.1%.

[0063] Clearly, the silicon carbide single crystal growth apparatus provided in this embodiment of the invention produces silicon carbide single crystals with a diameter of 200 mm that exhibit superior quality uniformity compared to existing technologies. Furthermore, existing technologies suffer from more severe quality inhomogeneity issues when growing larger silicon carbide single crystals. Therefore, the silicon carbide single crystal growth apparatus provided by this invention demonstrates significant effectiveness in obtaining uniform silicon carbide single crystals and in growing larger silicon carbide single crystals.

[0064] The terms "first" and "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units may include steps or units not listed, but rather steps or units not listed.

[0065] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A silicon carbide single crystal growth apparatus, comprising a crucible (10) for loading silicon carbide raw materials, characterized in that, It also includes a flow guide (20) disposed inside the crucible (10); The top of the crucible (10) is used to fix the seed crystal (30). After the crucible (10) is loaded with silicon carbide raw material, the lower end of the guide section (20) is lower than the upper surface of the silicon carbide raw material in the crucible (10) to divide the silicon carbide raw material into multiple regions. The upper end of the guide section (20) is higher than the upper surface of the silicon carbide raw material of the crucible (10). After the silicon carbide raw material in multiple regions sublimates into the gas phase, it moves upward under the guidance of the guide section (20) and contacts the seed crystal (30) to suppress the gas phase silicon carbide raw material from gathering in the central region of the seed crystal, so that the seed crystal surface is uniformly deposited. The flow guide (20) is configured as a vertically arranged multi-layered concentric cylinder; The flow guide (20) is concentrically arranged with the crucible (10), and the flow guide (20) passes evenly through the bisecting point on the radius of the crucible (10); The vertical distance between the lower end of the guide section (20) and the upper surface of the silicon carbide raw material in the crucible (10) is a first preset distance; the range of the first preset distance is 1 / 3 to 1 / 2 of the height of the silicon carbide raw material; The vertical distance between the upper end of the guide section (20) and the lower plane of the seed crystal (30) is a second preset distance; the range of the second preset distance is 10-200mm; The guide part (20) is made of one or more of tungsten, rhenium, osmium, niobium, molybdenum, iridium and tantalum with a purity greater than 99.9%.

2. The silicon carbide single crystal growth apparatus as described in claim 1, characterized in that, The flow guide (20) is configured as a vertically arranged single-layer cylinder.

3. The silicon carbide single crystal growth apparatus as described in claim 2, characterized in that, The flow guide (20) is concentrically arranged with the crucible (10), and the flow guide (20) passes through the radius center of the crucible (10).

4. The silicon carbide single crystal growth apparatus as described in claim 1, characterized in that, The lower end of the guide section (20) is in contact with the bottom of the crucible (10).

5. The silicon carbide single crystal growth apparatus as described in claim 1, characterized in that, The guide section (20) is made of graphite with an impurity content of less than 50 ppm.

6. The silicon carbide single crystal growth apparatus as described in claim 1, characterized in that, The guide section (20) is made of graphite with an impurity content of less than 5 ppm.

7. The silicon carbide single crystal growth apparatus as described in claim 1, characterized in that, The guide part (20) is made of one or more of tungsten, rhenium, osmium, niobium, molybdenum, iridium and tantalum with a purity greater than 99.99%.

8. The silicon carbide single crystal growth apparatus as described in claim 1, characterized in that, The guide part (20) is made of one or more of the following materials with a purity greater than 99.9%: tungsten carbide, rhenium carbide, osmium carbide, niobium carbide, molybdenum carbide, iridium carbide and tantalum carbide.

9. The silicon carbide single crystal growth apparatus as described in claim 1, characterized in that, The guide part (20) is made of one or more of the following materials with a purity greater than 99.99%: tungsten carbide, rhenium carbide, osmium carbide, niobium carbide, molybdenum carbide, iridium carbide and tantalum carbide.

10. The silicon carbide single crystal growth apparatus as described in claim 1, characterized in that, The guide section (20) is made of graphite with one or more coatings of tungsten, rhenium, osmium, niobium, molybdenum, iridium and tantalum with a purity greater than 99.99%.

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