Silicon carbide crystal growing device

Abstract

The invention provides a silicon carbide crystal growing device, and relates to the technical field of silicon carbide crystal manufacturing, the silicon carbide crystal growing device comprises a guide cylinder, the guide cylinder is located in a device main body, the guide cylinder and a seed crystal support jointly define a crystal growing cavity opened towards a raw material cavity, and one side, facing the inside of the crystal growing cavity, of the seed crystal support is provided with seed crystals; the guide cylinder comprises at least two arc-shaped cylinder parts which are sequentially distributed in the circumferential direction, and the at least two arc-shaped cylinder parts are suitable for outward movement and separation in the radial direction of the guide cylinder when silicon carbide crystals in the crystal growth cavity grow. According to the silicon carbide crystal growing device disclosed by the embodiment of the invention, when the silicon carbide crystal grows in the crystal growing cavity in the radial direction, the at least two arc-shaped barrel parts of the guide barrel can move outwards in the radial direction to be separated, so that the radial growth of the silicon carbide crystal can be prevented from being limited, the internal stress in the silicon carbide crystal is weakened, and the quality of the silicon carbide crystal is improved; the silicon carbide crystal growth device is simple in structure, better in using effect and wider in application range.

Description

Technical Field

[0001] The present invention relates to the technical field of silicon carbide crystal manufacturing, and in particular to a silicon carbide crystal growing device. Background Art

[0002] The silicon carbide crystal growth device decomposes solid silicon carbide raw material into gaseous components at high temperatures. Driven by the temperature gradient, the gaseous substances diffuse toward the low-temperature zone and then recrystallize on the surface of the seed crystal, forming a high-quality silicon carbide single crystal. A guide tube is provided within the silicon carbide crystal growth device to guide the gaseous substances decomposed from the raw material toward the seed crystal. However, the existing guide tube restricts the radial growth of the silicon carbide crystal, causing the internal stress of the silicon carbide crystal to deteriorate, which in turn affects the quality of the silicon carbide crystal, leaving room for improvement. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a silicon carbide crystal growth device with a simple structure that can reduce internal stress in the silicon carbide crystal, improve the quality of the silicon carbide crystal, and enhance its reliability.

[0004] According to an embodiment of the present invention, a silicon carbide crystal growth device includes: a device body, a raw material chamber is formed in the device body, the raw material chamber is used to hold and react silicon carbide powder, and the device body is equipped with a seed crystal holder above the raw material chamber; a guide tube, the guide tube is located in the device body, the guide tube and the seed crystal holder together define a crystal growth chamber open to the raw material chamber, a seed crystal is provided on the side of the seed crystal holder facing the crystal growth chamber, the guide tube includes at least two arc-shaped cylinder portions distributed in sequence along the circumferential direction, and at least two of the arc-shaped cylinder portions are suitable for moving radially outward and separating along the guide tube when silicon carbide crystals grow in the crystal growth chamber.

[0005] According to the silicon carbide crystal growth device of an embodiment of the present invention, by setting the guide tube to at least two arc-shaped cylinder portions distributed in sequence along the circumferential direction, when the silicon carbide crystal grows radially in the crystal growth chamber, the at least two arc-shaped cylinder portions of the guide tube can move radially outward and separate, thereby avoiding restricting the radial growth of the silicon carbide crystal, weakening the internal stress in the silicon carbide crystal, improving the quality of the silicon carbide crystal, and thereby improving the reliability of the silicon carbide crystal growth device. The structure is simple, the use effect is better, and the scope of application is wider.

[0006] According to some embodiments of the present invention, the silicon carbide crystal growth device further includes a convexity adjusting member, which is installed in the device body and located radially outside the guide tube. A movable gap is provided between the convexity adjusting member and the guide tube, and the arc-shaped cylinder portion is limited and pressed against the convexity adjusting member when moving outward to the maximum position.

[0007] According to some embodiments of the silicon carbide crystal growth device of the present invention, an annular adjustment portion protruding radially inward is formed on the upper portion of the inner circumferential wall of the convexity adjusting member, and the inner diameter of the annular adjustment portion is smaller than the inner diameter of the lower portion of the convexity adjusting member, and the gap between the arc-shaped cylindrical portion and the annular adjustment portion is smaller than the gap between the arc-shaped cylindrical portion and the inner wall of the convexity adjusting member.

[0008] According to some embodiments of the silicon carbide crystal growth device of the present invention, the inner diameter of the annular adjustment portion is set to R1, the inner diameter of the lower portion of the convexity adjustment member is set to R2, and the outer diameter of the convexity adjustment member is set to R3, and satisfies: 0<R2-R1<1 / 2(R3-R2).

[0009] According to some embodiments of the silicon carbide crystal growth apparatus of the present invention, the width dimension of the gap between the outer peripheral wall of the guide cylinder and the inner peripheral wall of the annular adjustment portion is set to z and satisfies: 3mm≤z≤10mm.

[0010] According to some embodiments of the silicon carbide crystal growth device of the present invention, the device body is provided with a first exhaust channel, and the guide tube is provided with a second exhaust channel. The first exhaust channel is connected to the second exhaust channel and is used to discharge the gas in the crystal growth chamber to outside the device body.

[0011] According to some embodiments of the silicon carbide crystal growth device of the present invention, the device body is provided with multiple first exhaust channels, each of the arc-shaped cylinders is provided with at least one second exhaust channel, and the multiple first exhaust channels and the multiple second exhaust channels are connected one-to-one.

[0012] According to some embodiments of the present invention, in the silicon carbide crystal growth apparatus, the diameter of the first exhaust channel is set to R4 and satisfies: 2mm≤R4≤7mm;

[0013] And / or, the diameter of the second exhaust channel is set to R5 and satisfies: 2mm≤R5≤7mm.

[0014] According to some embodiments of the silicon carbide crystal growth device of the present invention, the arc-shaped cylinder portion includes a crystallization cylinder segment and a guide cylinder segment connected in the axial direction, the crystallization cylinder segment is connected to the seed crystal holder, and the guide cylinder segment is connected to an end of the crystallization cylinder segment away from the seed crystal holder, and the inner diameter of the guide cylinder segment is configured to gradually increase in a direction away from the crystallization cylinder segment;

[0015] The difference between the minimum inner diameter of the crystallization cylinder segment and the maximum outer diameter of the seed crystal is set to x, and satisfies: 1mm≤x≤5mm.

[0016] According to some embodiments of the present invention, the silicon carbide crystal growth apparatus further includes a plurality of stabilizer crucibles, wherein the stabilizer crucibles are used to hold a crystal stabilizer, and the plurality of stabilizer crucibles are distributed in the silicon carbide powder in a spirally spaced manner along the vertical direction.

[0017] According to some embodiments of the present invention, in the silicon carbide crystal growth apparatus, a distance h1 is defined between the uppermost stabilizer crucible in the vertical direction and the upper surface of the silicon carbide powder, and the condition h1≤5mm is satisfied.

[0018] And / or, a distance h2 between a stabilizer crucible located at the bottom in the vertical direction among the plurality of stabilizer crucibles and the lower surface of the silicon carbide powder is satisfied, and h2 ≥ 5 mm.

[0019] According to some embodiments of the silicon carbide crystal growth apparatus of the present invention, the ratio of the total mass of the crystal stabilizers contained in the plurality of stabilizer crucibles to the total mass of the silicon carbide powder is y, and satisfies: 0.03%≤y≤0.08%.

[0020] According to some embodiments of the present invention, the silicon carbide crystal growth apparatus comprises a first silicon carbide powder and a second silicon carbide powder, wherein the first silicon carbide powder is located below the second silicon carbide powder;

[0021] The particle size of the first silicon carbide powder is set to r1 and satisfies: 0.5 mm ≤ r1 ≤ 2 mm; and / or the particle size of the second silicon carbide powder is set to r2 and satisfies: 2 mm ≤ r2 ≤ 5 mm.

[0022] According to some embodiments of the silicon carbide crystal growth device of the present invention, the device body includes a crucible assembly and a seed crystal holder assembly, the raw material chamber is formed in the crucible assembly, the crystal growth chamber is formed in the seed crystal holder assembly, a filter plate holder is installed between the crucible assembly and the seed crystal holder assembly, and the filter plate holder is installed with a filter plate located between the raw material chamber and the crystal growth chamber.

[0023] According to some embodiments of the silicon carbide crystal growth device of the present invention, the crucible assembly includes an outer crucible and an inner crucible, the inner crucible is installed in the outer crucible, the raw material chamber is formed in the inner crucible, a heating space is defined between the bottom of the inner crucible and the bottom of the outer crucible, and a heating element is provided in the heating space.

[0024] According to some embodiments of the silicon carbide crystal growth apparatus of the present invention, there are x heating elements provided, and the condition x≤4 is satisfied.

[0025] According to some embodiments of the silicon carbide crystal growth apparatus of the present invention, the filter plate support is formed with an escape space, the escape space is connected between the crystal growth chamber and the raw material chamber, and at least a portion of the filter plate in the vertical direction is arranged opposite to the escape space;

[0026] The filter plate is provided with a plurality of filter holes distributed at intervals, the aperture of the filter hole is set to r3, and satisfies: 50um≤r3≤500um.

[0027] According to some embodiments of the silicon carbide crystal growth apparatus of the present invention, the seed crystal holder assembly is constructed of a high-temperature refractory metal material, or the seed crystal holder assembly is provided with a high-temperature refractory metal coating.

[0028] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0030] Figure 1 is a schematic structural diagram of a silicon carbide crystal growth apparatus according to an embodiment of the present invention;

[0031] Figure 2 is a structural schematic diagram of a guide tube according to an embodiment of the present invention;

[0032] Figure 3 FIG. 4 is a schematic diagram of the distribution of multiple stabilizer crucibles according to an embodiment of the present invention.

[0033] Reference numerals:

[0034] Silicon carbide crystal growth apparatus 100,

[0035] Seed crystal holder assembly 1, seed crystal holder 11, first exhaust channel 111, outer ring cylinder 12, guide cylinder 13, arc cylinder portion 131, crystallization cylinder section 132, guide cylinder section 133, second exhaust channel 134, crystal growth chamber 14, convexity adjustment member 15, annular adjustment portion 151,

[0036] Crucible assembly 2, outer crucible 21, inner crucible 22, raw material chamber 23, stabilizer crucible 24, heating space 25, heating element 26,

[0037] Filter plate holder 3, filter plate 31, silicon carbide crystal 4, first silicon carbide powder 5, second silicon carbide powder 6. DETAILED DESCRIPTION

[0038] 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.

[0039] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, features defined as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0040] 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.

[0041] Reference below Figure 1-Figure 3 The silicon carbide crystal growing apparatus 100 according to an embodiment of the present invention has a simple structure, can reduce the internal stress in the silicon carbide crystal 4, improve the quality of the silicon carbide crystal 4, and enhance the reliability of use.

[0042] like Figure 1-Figure 3 As shown, a silicon carbide crystal growth device 100 according to an embodiment of the present invention includes: a device body and a guide tube 13.

[0043] A raw material chamber 23 is formed in the main body of the device. The raw material chamber 23 is used to hold and react silicon carbide powder. A seed crystal holder 11 is installed above the raw material chamber 23 in the main body of the device. The guide tube 13 is located in the main body of the device. The guide tube 13 and the seed crystal holder 11 jointly define a crystal growth chamber 14 open to the raw material chamber 23. A seed crystal is provided on the side of the seed crystal holder 11 facing the crystal growth chamber 14. The guide tube 13 includes at least two arc-shaped cylindrical portions 131 distributed in sequence along the circumferential direction. The at least two arc-shaped cylindrical portions 131 are suitable for moving radially outward and separating along the guide tube 13 when the silicon carbide crystal 4 in the crystal growth chamber 14 grows.

[0044] Among them, the silicon carbide crystal growth device 100 can decompose solid powdered silicon carbide raw materials into gaseous components at high temperature, and the gas phase material diffuses to the low temperature zone driven by the temperature gradient, and then recrystallizes on the surface of the seed crystal to form high-quality silicon carbide single crystal.

[0045] Specifically, the device body is arranged at the outermost side of the silicon carbide crystal growth device 100, and the silicon carbide crystal 4 can be prepared in the device body. A raw material chamber 23 is formed in the device body, and the raw material chamber 23 is located at the lower part of the device body. The raw material chamber 23 is used to hold silicon carbide powder, and when the lower part of the device body is heated, the silicon carbide powder in the raw material chamber 23 can react to decompose into gaseous components. The device body is also provided with a seed crystal holder 11, which is installed above the raw material chamber 23 and is separated from the silicon carbide powder in the raw material chamber 23. The device body is also provided with a guide tube 13, which is arranged in the device body. The guide tube 13 and the seed crystal holder 11 jointly define a crystal growth chamber 14. The crystal growth chamber 14 is located above the raw material chamber 23, and the crystal growth chamber 14 is open to the raw material chamber 23.

[0046] A seed crystal is provided on the side of the seed crystal holder 11 facing the crystal growth chamber 14. The silicon carbide powder in the raw material chamber 23 will decompose into gaseous components after heating and diffuse to the low-temperature area. The temperature of the crystal growth chamber 14 is relatively low, so that the decomposed gaseous substances can diffuse into the crystal growth chamber 14. The guide tube 13 can guide the decomposed gaseous substances to the seed crystal, so that the gaseous substances can recrystallize on the surface of the seed crystal to form high-quality silicon carbide crystals 4, thereby ensuring the preparation effect.

[0047] Furthermore, the guide tube 13 includes at least two arc-shaped cylinder portions 131, that is, the arc-shaped cylinder portions 131 can be set to two, three or four, etc. In this embodiment, the arc-shaped cylinder portions 131 are set to three, and at least two arc-shaped cylinder portions 131 are distributed in sequence along the circumferential direction, and can together constitute an annular guide tube 13, the crystal growth chamber 14 is located in at least two arc-shaped cylinder portions 131, and the seed crystal is also located in at least two arc-shaped cylinder portions 131.

[0048] During the reaction process, silicon carbide crystals 4 can be formed on the surface of the seed crystal, and the axial and radial sizes of the silicon carbide crystals 4 gradually increase. When the silicon carbide crystals 4 contact at least two arc-shaped cylindrical portions 131 and continue to grow, they will exert a radially outward force on at least two arc-shaped cylindrical portions 131, thereby allowing at least two arc-shaped cylindrical portions 131 to move radially outward and separate, thereby avoiding the guide tube 13 from restricting the radial growth of the silicon carbide crystals 4, thereby weakening the internal stress in the silicon carbide crystals 4, improving the quality of the silicon carbide crystals 4, and thereby improving the reliability of the silicon carbide crystal growth device 100.

[0049] In actual setting, at least two arc-shaped cylinders 131 can be set to be equal in size to ensure that the forces exerted by each arc-shaped cylinder 131 on the silicon carbide crystal 4 are the same when the silicon carbide crystal 4 grows, thereby ensuring the uniformity of the quality of the silicon carbide crystal 4.

[0050] According to the silicon carbide crystal growth device 100 of the embodiment of the present invention, by setting the guide tube 13 to at least two arc-shaped cylinder portions 131 distributed in sequence along the circumferential direction, when the silicon carbide crystal 4 grows radially in the crystal growth chamber 14, the at least two arc-shaped cylinder portions 131 of the guide tube 13 can move radially outward and separate, thereby avoiding restricting the radial growth of the silicon carbide crystal 4, thereby weakening the internal stress in the silicon carbide crystal 4, improving the quality of the silicon carbide crystal 4, and further improving the reliability of the silicon carbide crystal growth device 100, with a simple structure, better use effect, and a wider range of applications.

[0051] In some embodiments, the silicon carbide crystal growth device 100 also includes a convexity adjusting member 15, which is installed in the device body and located radially outside the guide tube 13. A movable gap is provided between the convexity adjusting member 15 and the guide tube 13, and the arc-shaped cylinder portion 131 is limited and pressed against the convexity adjusting member 15 when moving outward to the maximum position.

[0052] Specifically, if Figure 1As shown, the silicon carbide crystal growth device 100 is also provided with a convexity adjusting member 15, which is constructed in an annular shape. The convexity adjusting member 15 is arranged in the device body and is located between the inner wall of the device body and the guide tube 13, that is, the convexity adjusting member 15 is located radially outside the guide tube 13, and a movable gap is provided between the convexity adjusting member 15 and the guide tube 13, so that the convexity adjusting member 15 and the guide tube 13 are radially spaced apart and distributed. When the silicon carbide crystal 4 is growing, it can push at least two arc-shaped cylinder portions 131 of the guide tube 13 to move radially in the movable gap and separate circumferentially to avoid the guide tube 13 restricting the radial growth of the silicon carbide crystal 4, so as to weaken the internal stress in the silicon carbide crystal 4, and when the arc-shaped cylinder portion 131 moves outward to the maximum position, the outer peripheral wall of the arc-shaped cylinder portion 131 can be limited and pressed against the convexity adjusting member 15 to avoid the radial growth size of the silicon carbide crystal 4 being too large, thereby improving the quality of the silicon carbide crystal 4.

[0053] In some embodiments, an annular adjustment portion 151 protruding radially inward is formed on the upper portion of the inner circumferential wall of the convexity adjusting member 15, and the inner diameter of the annular adjustment portion 151 is smaller than the inner diameter of the lower portion of the convexity adjusting member 15, and the gap between the arc-shaped cylindrical portion 131 and the annular adjustment portion 151 is smaller than the gap between the arc-shaped cylindrical portion 131 and the inner wall of the convexity adjusting member 15.

[0054] Specifically, the convexity adjusting member 15 is located on the outer side of the guide tube 13 in the radial direction, and Figure 1 As shown, the convexity adjusting member 15 is formed with an annular adjusting portion 151, which is formed on the upper part of the inner circumferential wall of the convexity adjusting member 15 and protrudes radially inward, that is, the annular adjusting portion 151 is protruded toward the guide tube 13, so that the inner diameter of the annular adjusting portion 151 is smaller than the inner diameter of the lower part of the convexity adjusting member 15, so that the inner diameter of the upper part of the convexity adjusting member 15 is smaller than the inner diameter of the lower part of the convexity adjusting member 15, so that the upper part of the convexity adjusting member 15 is arranged close to the seed crystal, and the lower part of the convexity adjusting member 15 is arranged away from the seed crystal.

[0055] In this way, the upper part of the convexity adjusting member 15 corresponds to the initial growth stage of the silicon carbide crystal 4. The upper part of the convexity adjusting member 15 is arranged close to the seed crystal, so that the temperature of the edge of the silicon carbide crystal 4 is high, and the airflow is gathered into the seed crystal, which can make the silicon carbide crystal 4 grow convexly in the initial stage, and make the initial nucleation point inside the silicon carbide crystal 4, rather than at the edge, thereby avoiding the introduction of external miscellaneous crystals.

[0056] The lower part of the convexity adjusting member 15 corresponds to the middle and late stages of the growth of the silicon carbide crystal 4. The lower part of the convexity adjusting member 15 is set away from the seed crystal, which reduces the heating efficiency of the convexity adjusting member 15, and the radial temperature gradient of the silicon carbide crystal 4 gradually decreases. The silicon carbide crystal 4 also gradually changes from a relatively convex morphology to a slightly convex morphology, which can improve the uniform stacking of silicon carbide molecules and thereby improve the crystallization quality of the silicon carbide crystal 4.

[0057] In some embodiments, the inner diameter of the annular adjustment portion 151 is set to R1, the inner diameter of the lower portion of the convexity adjustment member 15 is set to R2, the outer diameter of the convexity adjustment member 15 is set to R3, and satisfies: 0<R2-R1<1 / 2(R3-R2).

[0058] Specifically, if Figure 1 As shown, the annular adjustment portion 151 is provided to protrude inwardly at the upper portion of the convexity adjusting member 15, and the inner diameter of the annular adjustment portion 151 is set to R1, the inner diameter of the lower portion of the convexity adjusting member 15 is set to R2, and the outer diameter of the annular adjustment portion 151 is set to R3, and satisfies: 0<R2-R1<1 / 2(R3-R2), R2-R1 is the difference between the inner diameter of the lower portion of the convexity adjusting member 15 and the inner diameter of the annular adjustment portion 151, and R2-R1 is set to be greater than 0, that is, the inner diameter of the lower portion of the convexity adjusting member 15 is set to be greater than the inner diameter of the annular adjustment portion 151, so that the annular adjustment portion 151 can protrude radially inward.

[0059] Furthermore, R3-R2 is the difference between the outer diameter of the convexity adjusting member 15 and the inner diameter of the lower part of the convexity adjusting member 15, and half of the difference is set to be greater than the difference between the inner diameter of the lower part of the convexity adjusting member 15 and the inner diameter of the annular adjusting portion 151, thereby ensuring the thickness of the main body of the convexity adjusting member 15 and preventing excessive difference in heating performance between the upper and lower parts of the convexity adjusting member 15, resulting in large differences in the early and middle and late growth of the silicon carbide crystal 4, thereby causing defects, and improving the crystallization quality of the silicon carbide crystal 4.

[0060] In some embodiments, the width of the gap between the outer circumferential wall of the guide tube 13 and the inner circumferential wall of the annular adjustment portion 151 is set to z and satisfies: 3 mm ≤ z ≤ 10 mm.

[0061] Specifically, the guide tube 13 is arranged in the convexity adjusting member 15, and there is a gap between the outer peripheral wall of the guide tube 13 and the inner peripheral wall of the annular adjusting portion 151 of the convexity adjusting member 15. The width dimension of the gap is set to z and satisfies: 3mm≤z≤10mm, that is, the width dimension z of the gap between the outer peripheral wall of the guide tube 13 and the inner peripheral wall of the annular adjusting portion 151 can be set to 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm, 10mm, or any value between 3mm and 10mm.

[0062] In this way, the width dimension z of the gap between the outer peripheral wall of the guide tube 13 and the inner peripheral wall of the annular adjustment part 151 is set to satisfy: 3mm≤z≤10mm, which can not only reserve a certain space for the outward expansion of the guide tube 13, but also avoid the outward expansion diameter being too large, which will cause the silicon carbide crystal 4 to deposit too quickly in the horizontal direction, causing an increase in basal plane dislocations, an increase in stacking faults, and the generation of polycrystalline and cracks at the edges, thereby improving the crystallization quality of the silicon carbide crystal 4.

[0063] In some embodiments, the device body is provided with a first exhaust channel 111 , and the guide tube 13 is provided with a second exhaust channel 134 . The first exhaust channel 111 is connected to the second exhaust channel 134 and is used to discharge the gas in the crystal growth chamber 14 out of the device body.

[0064] Specifically, if Figure 1 As shown, the device body is also provided with a first exhaust channel 111, and the guide tube 13 is provided with a second exhaust channel 134, and when the guide tube 13 is installed in the device body, the first exhaust channel 111 and the second exhaust channel 134 can be connected, so that the crystal growth chamber 14 can be connected with the outside world through the second exhaust channel 134 and the first exhaust channel 111. When the silicon carbide crystal 4 in the crystal growth chamber 14 grows, excess gas will be generated in the crystal growth chamber 14, and the gas can be discharged to the outside world through the second exhaust channel 134 and the first exhaust channel 111, thereby avoiding the silicon carbide crystal 4 in the crystal growth chamber 14 from becoming polycrystalline due to oversaturation of silicon carbide gas, so as to improve the crystallization quality of the silicon carbide crystal 4.

[0065] In some embodiments, the device body is provided with a plurality of first exhaust channels 111 , each arc-shaped cylindrical portion 131 is provided with at least one second exhaust channel 134 , and the plurality of first exhaust channels 111 and the plurality of second exhaust channels 134 are connected in a one-to-one correspondence.

[0066] Specifically, if Figure 1-Figure 2As shown, the guide tube 13 is provided with at least two arc-shaped cylinder portions 131, and each arc-shaped cylinder portion 131 is provided with at least one second exhaust channel 134, that is, each arc-shaped cylinder portion 131 can be provided with one, two or more second exhaust channels 134, and the device body is provided with multiple first exhaust channels 111, that is, the device body can be provided with one, two or more first exhaust channels 111, and the multiple first exhaust channels 111 and the multiple second exhaust channels 134 are connected one by one, so that each arc-shaped cylinder portion 131 can exhaust to the corresponding first exhaust channel 111 through the second exhaust channel 134, and thus the crystal growth chamber 14 can be exhausted to the outside at multiple locations along the circumference at the same time to ensure the uniformity of gas distribution in the crystal growth chamber 14, thereby improving the consistency of the crystal growth conditions of the silicon carbide crystal 4 at various locations along the circumference, and improving the quality of the silicon carbide crystal 4.

[0067] In some embodiments, the diameter of the first exhaust channel 111 is set to R4 and satisfies: 2mm≤R4≤7mm, and / or, the diameter of the second exhaust channel 134 is set to R5 and satisfies: 2mm≤R5≤7mm, that is, only the diameter R4 of the first exhaust channel 111 is set to satisfy: 2mm≤R4≤7mm, or only the diameter R5 of the second exhaust channel 134 is set to satisfy: 2mm≤R5≤7mm, or the diameter R4 of the first exhaust channel 111 is set to satisfy: 2mm≤R4≤7mm, and the diameter R5 of the second exhaust channel 134 is set to satisfy: 2mm≤R5≤7mm.

[0068] In this embodiment, the diameter R4 of the first exhaust channel 111 is set to satisfy: 2mm≤R4≤7mm, and the diameter R5 of the second exhaust channel 134 is set to satisfy: 2mm≤R5≤7mm, that is, the diameter R4 of the first exhaust channel 111 can be set to 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, or any value between 2mm and 7mm, and the diameter R5 of the second exhaust channel 134 can be set to 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, or any value between 2mm and 7mm.

[0069] If the diameters of the first exhaust channel 111 and the second exhaust channel 134 are set too small, less silicon carbide gas will overflow from the crystal growth chamber 14, and polycrystals will be produced at the edge of the silicon carbide crystal 4 in an oversaturated gas state, affecting the quality of the silicon carbide crystal 4. If the diameters of the first exhaust channel 111 and the second exhaust channel 134 are set too large, more silicon carbide gas will overflow, affecting the growth rate of the silicon carbide crystal 4, and even causing an imbalance in the gas partial pressure in the crystal growth chamber 14, resulting in the generation of polymorphs.

[0070] Thus, the diameter R4 of the first exhaust channel 111 is set to satisfy: 2mm≤R4≤7mm, and the diameter R5 of the second exhaust channel 134 is set to satisfy: 2mm≤R5≤7mm, which can improve the quality of the silicon carbide crystal 4 while ensuring the growth rate of the silicon carbide crystal 4.

[0071] Preferably, the diameter R4 of the first exhaust channel 111 is set to satisfy: 3 mm ≤ R4 ≤ 5 mm, and the diameter R5 of the second exhaust channel 134 is set to satisfy: 3 mm ≤ R5 ≤ 5 mm.

[0072] In some embodiments, the arc-shaped cylinder portion 131 includes a crystallization cylinder segment 132 and a guide cylinder segment 133 connected along the axial direction, the crystallization cylinder segment 132 is connected to the seed crystal holder 11, and the guide cylinder segment 133 is connected to the end of the crystallization cylinder segment 132 away from the seed crystal holder 11. The inner diameter of the guide cylinder segment 133 is constructed to gradually increase in the direction away from the crystallization cylinder segment 132, wherein the difference between the minimum inner diameter of the crystallization cylinder segment 132 and the maximum outer diameter of the seed crystal is set to x, and satisfies: 1mm≤x≤5mm.

[0073] Specifically, if Figure 1 As shown, the arc-shaped cylinder portion 131 is provided with a crystallization cylinder section 132 and a guide cylinder section 133, and the crystallization cylinder section 132 and the guide cylinder section 133 are connected in sequence along the axial direction, and the crystallization cylinder section 132 is connected to the seed crystal holder 11, that is, the crystallization cylinder section 132 is arranged close to the seed crystal holder 11, so that the silicon carbide crystal 4 first contacts the crystallization cylinder section 132 during growth, and the guide cylinder section 133 is connected to the end of the crystallization cylinder section 132 away from the seed crystal holder 11, and the inner diameter of the guide cylinder section 133 is constructed to gradually increase in the direction away from the crystallization cylinder section 132, so that the inner diameter of the guide cylinder section 133 at the end away from the crystallization cylinder section 132 is the largest, and the inner diameter of the guide cylinder section 133 gradually decreases in the direction close to the crystallization cylinder section 132, so that the gaseous substances generated by the silicon carbide powder in the raw material chamber 23 during the reaction are guided along the guide cylinder section 133 to the crystallization cylinder section 132, and then accurately guided to the seed crystal on the seed crystal holder 11, thereby improving the crystallization rate.

[0074] And the difference between the minimum inner diameter of the crystallization cylinder segment 132 and the maximum outer diameter of the seed crystal is set to x, and satisfies: 1mm≤x≤5mm, that is, the difference x between the minimum inner diameter of the crystallization cylinder segment 132 and the maximum outer diameter of the seed crystal is set to 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, or any value between 1mm and 5mm. In this way, if the difference x between the minimum inner diameter of the crystallization cylinder segment 132 and the maximum outer diameter of the seed crystal is set too small, it will be difficult to assemble, and if the difference x between the minimum inner diameter of the crystallization cylinder segment 132 and the maximum outer diameter of the seed crystal is set too large, it will easily cause polycrystalline, cracks, etc. in the silicon carbide crystal 4, thereby ensuring the convenience of assembly while improving the quality of the silicon carbide crystal 4.

[0075] Preferably, the difference x between the minimum inner diameter of the crystallization barrel segment 132 and the maximum outer diameter of the seed crystal is set to satisfy: 1 ​​mm ≤ x ≤ 3 mm.

[0076] In some embodiments, the silicon carbide crystal growing apparatus 100 further includes a plurality of stabilizer crucibles 24 , which are used to contain a crystal stabilizer. The plurality of stabilizer crucibles 24 are distributed in a spirally spaced manner along a vertical direction within the silicon carbide powder.

[0077] Specifically, if Figure 1 As shown, the silicon carbide crystal growth device 100 is also provided with a stabilizer crucible 24. The stabilizer crucible 24 can be set to multiple, that is, the stabilizer crucible 24 can be set to two, three or four, etc. The stabilizer crucible 24 is used to hold a crystal stabilizer. The crystal stabilizer can be set to a cerium-containing compound, and multiple stabilizer crucibles 24 are placed in the silicon carbide powder. When the silicon carbide powder reacts, the crystal stabilizers in the multiple stabilizer crucibles 24 can stabilize the 4H crystal form of silicon carbide, prevent the occurrence of 6H or 15R polymorphs, and improve the reaction stability.

[0078] And as Figure 3 As shown, multiple stabilizer crucibles 24 are distributed in a spiral shape in the vertical direction in the silicon carbide powder, so that stabilizer crucibles 24 are provided in multiple locations in the silicon carbide powder, thereby improving the uniformity of the crystal stabilizer acting on the silicon carbide powder and thus improving the use effect.

[0079] In some embodiments, the distance between the stabilizer crucible 24 located at the top in the vertical direction among the multiple stabilizer crucibles 24 and the upper surface of the silicon carbide powder is h1, and satisfies: h1≤5mm, and / or, the distance between the stabilizer crucible 24 located at the bottom in the vertical direction among the multiple stabilizer crucibles 24 and the lower surface of the silicon carbide powder is h2, and satisfies: h2≥5mm.

[0080] That is, only the distance h1 between the stabilizer crucible 24 located at the top along the vertical direction among the multiple stabilizer crucibles 24 and the upper surface of the silicon carbide powder is set to satisfy: h1≤5mm, and only the distance h2 between the stabilizer crucible 24 located at the bottom along the vertical direction among the multiple stabilizer crucibles 24 and the lower surface of the silicon carbide powder is set to satisfy: h2≥5mm. Also, the distance h1 between the stabilizer crucible 24 located at the top along the vertical direction among the multiple stabilizer crucibles 24 and the upper surface of the silicon carbide powder is set to satisfy: h1≤5mm, and at the same time, the distance h2 between the stabilizer crucible 24 located at the bottom along the vertical direction among the multiple stabilizer crucibles 24 and the lower surface of the silicon carbide powder is set to satisfy: h2≥5mm.

[0081] The distance h1 between the stabilizer crucible 24 located at the top in the vertical direction among the multiple stabilizer crucibles 24 and the upper surface of the silicon carbide powder can be set to 5mm, 4.5mm, 4mm, 3.5mm, 3mm, 2.5mm, 2mm, 1.5mm, 1mm, etc., and the distance h2 between the stabilizer crucible 24 located at the bottom in the vertical direction among the multiple stabilizer crucibles 24 and the lower surface of the silicon carbide powder can be set to 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, etc., and the distance between two adjacent stabilizer crucibles 24 in the vertical direction is set to be equal, so as to ensure the use effect of the crystal stabilizer in the stabilizer crucible 24 and improve the quality of the silicon carbide crystal 4.

[0082] In some embodiments, the ratio of the total mass of the crystal stabilizers contained in the plurality of stabilizer crucibles 24 to the total mass of the silicon carbide powder is y, and satisfies: 0.03%≤y≤0.08%.

[0083] Specifically, there are multiple stabilizer crucibles 24, and each stabilizer crucible 24 contains a crystal stabilizer. Multiple stabilizer crucibles 24 are placed in silicon carbide powder. The ratio of the total mass of the crystal stabilizers contained in the multiple stabilizer crucibles 24 to the total mass of the silicon carbide powder is y, and satisfies: 0.03%≤y≤0.08%, that is, the ratio y of the total mass of the crystal stabilizers contained in the multiple stabilizer crucibles 24 to the total mass of the silicon carbide powder can be set to 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, or any value between 0.03% and 0.08%.

[0084] In this way, when the total mass of the crystal stabilizer is too small, it cannot stabilize the single crystal form, and when the total mass of the crystal stabilizer is too much, it is easy to cause excessive impurities in the silicon carbide crystal 4, resulting in defects, microtubes, etc. Therefore, the ratio y of the total mass of the crystal stabilizer contained in the multiple stabilizer crucibles 24 to the total mass of the silicon carbide powder is set to meet the following conditions: 0.03% ≤ y ≤ 0.08%, which can avoid defects, microtubes, etc. in the silicon carbide crystal 4 while ensuring the reliability of the use of the crystal stabilizer.

[0085] In some embodiments, the silicon carbide powder includes a first silicon carbide powder 5 and a second silicon carbide powder 6, and the first silicon carbide powder 5 is located below the second silicon carbide powder 6, wherein the silicon powder particle size of the first silicon carbide powder 5 is set to r1 and satisfies: 0.5mm≤r1≤2mm, and / or, the silicon powder particle size of the second silicon carbide powder 6 is set to r2 and satisfies: 2mm≤r2≤5mm, that is, only the silicon powder particle size r1 of the first silicon carbide powder 5 can be set to satisfy: 0.5mm≤r1≤2mm, or only the silicon powder particle size r2 of the second silicon carbide powder 6 can be set to satisfy: 2mm≤r2≤5mm, and the silicon powder particle size r1 of the first silicon carbide powder 5 can also be set to satisfy: 0.5mm≤r1≤2mm, and the silicon powder particle size r2 of the second silicon carbide powder 6 can be set to satisfy: 2mm≤r2≤5mm.

[0086] Specifically, the silicon carbide powder is set to two types and includes a first silicon carbide powder 5 and a second silicon carbide powder 6. The first silicon carbide powder 5 and the second silicon carbide powder 6 are arranged in layers in the raw material chamber 23, and the first silicon carbide powder 5 is located below the second silicon carbide powder 6, that is, the first silicon carbide powder 5 is arranged away from the crystal growth chamber 14, and the second silicon carbide powder 6 is arranged away from the crystal growth chamber 14.

[0087] In this embodiment, the silicon powder particle size r1 of the first silicon carbide powder 5 is set to satisfy: 0.5 mm ≤ r1 ≤ 2 mm, and the silicon powder particle size r2 of the second silicon carbide powder 6 is set to satisfy: 2 mm ≤ r2 ≤ 5 mm, that is, the silicon powder particle size r1 of the first silicon carbide powder 5 can be set to 0.5 mm, 0.7 mm, 0.9 mm, 1.1 mm, 1.3 mm, 1.5 mm, 1.7 mm, 1.9 mm, 2 mm, or any value between 0.5 mm and 2 mm, and the silicon powder particle size r2 of the second silicon carbide powder 6 can be set to 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, or any value between 2 mm and 5 mm.

[0088] In this way, the silicon carbide powder at the bottom of the raw material chamber 23 is fine powder, and the silicon carbide powder at the top is coarse powder, and the setting height of the fine powder is d1, and the setting height of the coarse powder is d2, and it satisfies: (2 / 3)d1≤d2≤d1. At the same crystal growth temperature, the fine powder has a larger specific surface area, a higher sublimation efficiency, and a larger sublimation amount, and is the main source of silicon carbide gas in the silicon carbide crystal growth process; the coarse powder mainly plays the role of filtering and assisting growth; a large loading amount of fine powder is conducive to improving the crystal growth rate of silicon carbide, and at the same time, the minimum loading amount of coarse powder must be guaranteed, so that solid particles can be filtered while effectively growing the crystal, thereby ensuring the quality of the silicon carbide crystal 4.

[0089] In some embodiments, the device body includes a crucible assembly 2 and a seed crystal holder assembly 1, the raw material chamber 23 is formed in the crucible assembly 2, the crystal growth chamber 14 is formed in the seed crystal holder assembly 1, and a filter plate holder 3 is installed between the crucible assembly 2 and the seed crystal holder assembly 1. The filter plate holder 3 is installed with a filter plate 31 located between the raw material chamber 23 and the crystal growth chamber 14.

[0090] Specifically, if Figure 1 As shown, the device body is provided with a crucible assembly 2 and a seed crystal holder assembly 1, the seed crystal holder assembly 1 is installed above the crucible assembly 2, and the raw material cavity 23 is formed in the crucible assembly 2, and the crystal growth cavity 14 is formed in the seed crystal holder assembly 1, so that the crystal growth cavity 14 is located above the raw material cavity 23, the seed crystal holder assembly 1 is provided with an outer ring tube 12 and a seed crystal holder 11, the outer ring tube 12 is installed above the crucible assembly 2, and the seed crystal holder 11 is installed at one end of the outer ring tube 12 away from the crucible assembly 2, the inner diameter of the outer ring tube 12 is set to be larger than the inner diameter of the crucible assembly 2, so that a step portion is formed between the crucible assembly 2 and the outer ring tube 12.

[0091] A filter plate support 3 is installed between the crucible assembly 2 and the seed crystal support assembly 1. The filter plate support 3 is installed with a filter plate 31 located between the raw material chamber 23 and the crystal growth chamber 14. The gaseous substances generated by the silicon carbide powder during the reaction can be filtered through the filter plate 31 and diffused to the seed crystal to ensure the quality of the crystal. The step portion can limit the filter plate support 3 in the radial direction, and then limit the position of the filter plate 31 to ensure the reliability of the use of the filter plate 31.

[0092] In some embodiments, the crucible assembly 2 includes an outer crucible 21 and an inner crucible 22, the inner crucible 22 is installed in the outer crucible 21, the raw material chamber 23 is formed in the inner crucible 22, and a heating space 25 is defined between the bottom of the inner crucible 22 and the bottom of the outer crucible 21, and a heating element 26 is provided in the heating space 25.

[0093] Specifically, if Figure 1As shown, the crucible assembly 2 is provided with an outer crucible 21 and an inner crucible 22. The inner crucible 22 is arranged in the outer crucible 21, and a raw material cavity 23 is defined in the inner crucible 22, that is, silicon carbide powder can be placed in the inner crucible 22. The inner crucible 22 is constructed in an "H" shape, and a heating space 25 can be defined between its bottom and the bottom of the outer crucible 21, and a heating element 26 can be provided in the heating space 25. The heating performance of the bottom of the inner crucible 22 can be adjusted by the heating element 26, thereby adjusting the axial temperature gradient. The outer diameter of the inner crucible 22 and the inner diameter of the outer crucible 21 are set to be the same, which can prevent heat from overflowing from the gap between the inner crucible 22 and the outer crucible 21, thereby ensuring reliability in use.

[0094] In some embodiments, there are x heating elements 26 , and x≤4.

[0095] Specifically, a heating element 26 is provided in the heating space 25, and the number of the heating elements 26 is x, and satisfies: x≤4, that is, the number x of the heating elements 26 can be set to 4, 3, 2 or 1. In this way, the heating performance of the bottom of the inner crucible 22 can be adjusted by adjusting the number of the heating elements 26, and then the axial temperature gradient can be adjusted to meet different usage requirements. In actual settings, when the number of heating elements 26 is increased to 4, the axial temperature gradient of the thermal field is always small, and it is necessary to consider replacing a new thermal field to ensure the reliability of the thermal field.

[0096] In some embodiments, the filter plate support 3 is formed with an avoidance space, which is connected between the crystal growth chamber 14 and the raw material chamber 23, and the filter plate 31 is distributed opposite to the avoidance space at least in part along the vertical direction, wherein the filter plate 31 is provided with a plurality of filter holes distributed at intervals, and the aperture of the filter hole is set to r3, and satisfies: 50um≤r3≤500um.

[0097] Specifically, the filter plate 31 is installed on the filter plate holder 3, and the filter plate holder 3 is constructed as a ring structure. Figure 1 As shown, an escape space is formed in the middle of the filter plate holder 3, and the escape space is connected between the crystal growth chamber 14 and the raw material chamber 23. At least part of the filter plate 31 in the vertical direction is distributed opposite to the escape space, that is, part of the filter plate 31 in the vertical direction is distributed opposite to the escape space, or the filter plate 31 can be distributed opposite to the escape space in the vertical direction. A step structure is formed at the inner diameter of the filter plate holder 3, and the filter plate 31 can be snapped into the step structure, thereby limiting the radial position of the filter plate 31.

[0098] Among them, the maximum inner diameter of the filter plate support 3 is set to be equal to the maximum inner diameter of the bottom of the guide tube 13, which can avoid gas overflow, and the minimum inner diameter of the filter plate support 3 is consistent with the inner diameter of the upper part of the guide tube 13, thereby forming an effective gas transmission channel, and the maximum inner diameter of the bottom of the guide tube 13 and the maximum inner diameter of the filter plate support 3 are set to be the same, which can avoid the generation of dislocation steps in this area, and thus avoid the growth of polycrystalline at the dislocation steps.

[0099] Furthermore, the filter plate 31 can be made of a metal carbide, such as tantalum carbide or niobium carbide. The filter plate holder 3 is made of the same material as the filter plate 31, and the material parameters required are consistent with those of the filter plate 31. The filter plate 31 is provided with a plurality of spaced filter holes, each with an aperture r3 satisfying the following conditions: 50 μm ≤ r3 ≤ 500 μm. Specifically, the aperture r3 can be set to 50 μm, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, 450 μm, or 500 μm, or any value between 50 μm and 500 μm. Preferably, the aperture r3 satisfies the following conditions: 100 μm ≤ r3 ≤ 300 μm.

[0100] If the pore size of the filter plate 31 is set too small, it will hinder the upward transmission of silicon carbide gas, affecting the growth efficiency of silicon carbide crystals 4. If the pore size of the filter plate 31 is set too large, the effect of filtering out particulate matter will be reduced, and particulate matter will enter the interior of the silicon carbide crystals 4, affecting the quality of the silicon carbide crystals 4. Therefore, setting the pore size r3 of the filter hole to meet the following conditions: 50μm≤r3≤500μm can ensure the growth efficiency of the silicon carbide crystals 4 while also ensuring the quality of the silicon carbide crystals 4.

[0101] In addition, the porosity of the filter plate 31 is set to 30% to 70%. Preferably, the porosity of the filter plate 31 is set to 40% to 60%. If the porosity is too large, the effect of filtering particulate matter will be reduced, and the particulate matter will enter the interior of the silicon carbide crystal 4, which will affect the quality of the silicon carbide crystal 4. If the porosity is too small, it will affect the growth efficiency of the silicon carbide crystal 4. Setting the porosity to 30% to 70% can ensure the growth efficiency of the silicon carbide crystal 4 while ensuring the quality of the silicon carbide crystal 4.

[0102] In some embodiments, the seed crystal holder assembly 1 is constructed of a high-temperature refractory metal material, or the seed crystal holder assembly 1 is provided with a high-temperature refractory metal coating.

[0103] Specifically, if Figure 1As shown, the seed crystal holder assembly 1 is provided with an outer ring tube 12 and a seed crystal holder 11. The seed crystal holder assembly 1 can be constructed as a high-temperature refractory metal material, or the outer surface of the seed crystal holder assembly 1 is provided with a high-temperature refractory metal coating, and the seed crystal holder assembly 1 is provided with a guide tube 13 and a convexity adjusting member 15. The convexity adjusting member 15 can be constructed as a high-temperature refractory metal material, or the outer surface of the convexity adjusting member 15 is provided with a high-temperature refractory metal coating. In this way, the crystal growth chamber 14 can be ensured to be a "clean" area, and only silicon carbide gas exists in the crystal growth chamber 14. The influence of impurities such as floating carbon, carbon particles, and silicon droplets on the silicon carbide crystal 4 can be eliminated, thereby improving the quality of the silicon carbide crystal 4.

[0104] The base of the guide tube 13 is made of graphite, and a high-temperature refractory metal coating can also be provided on the outer surface of the guide tube 13. The material of the guide tube 13 is the same as that of the filter plate 31 and the filter plate support 3. Providing a high-temperature refractory metal coating on the outer surface of the guide tube 13 can avoid the large difference in thermal conductivity and resistivity of the high-temperature refractory metal material from graphite, which affects the growth of crystals.

[0105] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative uses of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0106] While 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 silicon carbide crystal growth device, characterized in that: include: A device body, wherein a raw material cavity (23) is formed in the device body, the raw material cavity (23) is used to contain and react silicon carbide powder, and a seed crystal holder (11) is installed above the raw material cavity (23) on the device body; A guide tube (13) is provided, wherein the guide tube (13) is located in the main body of the device, and the guide tube (13) and the seed crystal holder (11) jointly define a crystal growth chamber (14) open toward the raw material chamber (23); a seed crystal is provided on the side of the seed crystal holder (11) facing the crystal growth chamber (14); the guide tube (13) comprises at least two arc-shaped cylinder portions (131) distributed in sequence along the circumferential direction; and at least two of the arc-shaped cylinder portions (131) are adapted to move radially outward and separate along the guide tube (13) when the silicon carbide crystal (4) in the crystal growth chamber (14) grows.

2. The silicon carbide crystal growth device according to claim 1, characterized in that The invention also includes a convexity adjusting member (15), which is installed in the device body and located radially outside the guide tube (13). A movable gap is provided between the convexity adjusting member (15) and the guide tube (13), and the arc-shaped cylinder portion (131) is limitedly pressed against the convexity adjusting member (15) when it moves outward to a maximum position.

3. The silicon carbide crystal growth device according to claim 2, characterized in that An annular adjustment portion (151) protruding radially inward is formed on the upper portion of the inner peripheral wall of the convexity adjustment member (15), the inner diameter of the annular adjustment portion (151) is smaller than the inner diameter of the lower portion of the convexity adjustment member (15), and the gap between the arc-shaped cylindrical portion (131) and the annular adjustment portion (151) is smaller than the gap between the arc-shaped cylindrical portion (131) and the inner wall of the convexity adjustment member (15).

4. The silicon carbide crystal growth device according to claim 3, characterized in that The inner diameter of the annular adjustment portion (151) is set to R1, the inner diameter of the lower portion of the convexity adjustment member (15) is set to R2, and the outer diameter of the convexity adjustment member (15) is set to R3, and the following conditions are satisfied: 0<R2-R1<1 / 2(R3-R2).

5. The silicon carbide crystal growth device according to claim 3, characterized in that The width dimension of the gap between the outer peripheral wall of the guide tube (13) and the inner peripheral wall of the annular adjustment portion (151) is set to z, and satisfies: 3mm≤z≤10mm.

6. The silicon carbide crystal growth device according to claim 1, characterized in that The device body is provided with a first exhaust channel (111), and the guide tube (13) is provided with a second exhaust channel (134); the first exhaust channel (111) and the second exhaust channel (134) are communicated and are used to discharge the gas in the crystal growth chamber (14) to the outside of the device body.

7. The silicon carbide crystal growth device according to claim 6, characterized in that The device body is provided with a plurality of the first exhaust channels (111), each of the arc-shaped cylindrical portions (131) is provided with at least one of the second exhaust channels (134), and the plurality of the first exhaust channels (111) and the plurality of the second exhaust channels (134) are connected in a one-to-one correspondence.

8. The silicon carbide crystal growth apparatus according to claim 6, wherein: The diameter of the first exhaust channel (111) is set to R4 and satisfies: 2mm≤R4≤7mm; And / or, the diameter of the second exhaust channel (134) is set to R5, and satisfies: 2mm≤R5≤7mm.

9. The silicon carbide crystal growth apparatus according to claim 1, wherein: The arc-shaped cylinder portion (131) comprises a crystallization cylinder section (132) and a guide cylinder section (133) connected in the axial direction, the crystallization cylinder section (132) is connected to the seed crystal holder (11), the guide cylinder section (133) is connected to one end of the crystallization cylinder section (132) away from the seed crystal holder (11), and the inner diameter of the guide cylinder section (133) is configured to gradually increase in a direction away from the crystallization cylinder section (132); The difference between the minimum inner diameter of the crystallization barrel section (132) and the maximum outer diameter of the seed crystal is set to x, and satisfies: 1mm≤x≤5mm.

10. The silicon carbide crystal growth apparatus according to claim 1, wherein It also includes a plurality of stabilizer crucibles (24), which are used to hold a crystal stabilizer. The plurality of stabilizer crucibles (24) are distributed in a spiral shape in a vertical direction within the silicon carbide powder.

11. The silicon carbide crystal growth apparatus according to claim 10, wherein: The distance between the stabilizer crucible (24) located at the top in the vertical direction among the plurality of stabilizer crucibles (24) and the upper surface of the silicon carbide powder is h1, and the following condition is satisfied: h1≤5mm; And / or, the distance between the stabilizer crucible (24) located at the bottom in the vertical direction among the plurality of stabilizer crucibles (24) and the lower surface of the silicon carbide powder is h2, and satisfies: h2≥5mm.

12. The silicon carbide crystal growth apparatus according to claim 10, wherein: The ratio of the total mass of the crystal stabilizers contained in the plurality of stabilizer crucibles (24) to the total mass of the silicon carbide powder is y, and satisfies the following: 0.03%≤y≤0.08%.

13. The silicon carbide crystal growth apparatus according to claim 1, wherein The silicon carbide powder comprises a first silicon carbide powder (5) and a second silicon carbide powder (6), wherein the first silicon carbide powder (5) is located below the second silicon carbide powder (6); The particle size of the first silicon carbide powder (5) is set to r1 and satisfies the following conditions: 0.5 mm ≤ r1 ≤ 2 mm; and / or the particle size of the second silicon carbide powder (6) is set to r2 and satisfies the following conditions: 2 mm ≤ r2 ≤ 5 mm.

14. The silicon carbide crystal growth apparatus according to claim 1, wherein The device body comprises a crucible assembly (2) and a seed crystal holder assembly (1); the raw material chamber (23) is formed in the crucible assembly (2); the crystal growth chamber (14) is formed in the seed crystal holder assembly (1); a filter plate holder (3) is installed between the crucible assembly (2) and the seed crystal holder assembly (1); and the filter plate holder (3) is installed with a filter plate (31) located between the raw material chamber (23) and the crystal growth chamber (14).

15. The silicon carbide crystal growth apparatus according to claim 14, wherein: The crucible assembly (2) includes an outer crucible (21) and an inner crucible (22), wherein the inner crucible (22) is installed in the outer crucible (21), the raw material cavity (23) is formed in the inner crucible (22), a heating space (25) is defined between the bottom of the inner crucible (22) and the bottom of the outer crucible (21), and a heating element (26) is provided in the heating space (25).

16. The silicon carbide crystal growth apparatus according to claim 15, wherein: The number of the heating elements (26) is x, and the condition x≤4 is satisfied.

17. The silicon carbide crystal growth apparatus according to claim 14, wherein: The filter plate support (3) is formed with an escape space, the escape space being connected between the crystal growth chamber (14) and the raw material chamber (23), and at least a portion of the filter plate (31) in the vertical direction is arranged opposite to the escape space; The filter plate (31) is provided with a plurality of filter holes distributed at intervals, and the aperture of the filter hole is set to r3, and satisfies the following conditions: 50um≤r3≤500um.

18. The silicon carbide crystal growth apparatus according to claim 14, wherein: The seed crystal holder assembly (1) is constructed of a high-temperature refractory metal material, or the seed crystal holder assembly (1) is provided with a high-temperature refractory metal coating.

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