Silicon carbide single crystal growth device

Abstract

The utility model relates to the technical field of crystal growth, in particular to a silicon carbide single crystal growth device. The silicon carbide single crystal growth device comprises a crucible, a crucible cover and a first heat preservation layer, the crucible is provided with a cavity, the cavity comprises a raw material area and a growth area which are communicated with each other, the raw material area is used for containing silicon carbide raw materials, and the end, away from the raw material area, of the growth area is provided with an opening; the crucible cover is detachably arranged on the crucible and is used for shielding or opening the opening, and the crucible cover is also used for arranging a seed crystal; the first heat preservation layer is arranged in the cavity and surrounds the periphery of the raw material area. According to the silicon carbide single crystal growth device, the axial temperature gradient can be increased, so that the crystal growth speed is increased, and the growth of crystals with relatively large thickness is facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of crystal growth, in particular to a silicon carbide single crystal growth device. Background Art

[0002] Silicon carbide is widely used in the semiconductor field due to its excellent physical and chemical properties, including power electronics, optoelectronic devices, radio frequency devices and other fields.

[0003] The preparation method of silicon carbide single crystal includes physical vapor transport (PVT) method. The principle of PVT method is that silicon carbide raw material decomposes and sublimates in a high temperature zone, and is transported to the seed crystal under the action of the radial temperature gradient of the crystal growth environment to crystallize and grow into silicon carbide single crystal.

[0004] However, the silicon carbide single crystal growth device provided by the related technology is difficult to increase the axial temperature gradient, resulting in limited crystal growth rate and low raw material utilization rate, that is, it is difficult to increase the crystal growth rate and increase the raw material utilization rate, and it is also difficult to grow a crystal with a larger thickness. Utility Model Content

[0005] The utility model aims to provide a silicon carbide single crystal growth device, which can increase the axial temperature gradient to increase the crystal growth rate, improve the raw material utilization rate, and is conducive to growing a crystal with a larger thickness.

[0006] The embodiment of the utility model is achieved as follows:

[0007] The utility model provides a silicon carbide single crystal growth device, comprising:

[0008] A crucible, wherein the crucible has a chamber, wherein the chamber includes a raw material area and a growth area which are interconnected, wherein the raw material area is used to contain silicon carbide raw materials, and an end of the growth area away from the raw material area has an opening;

[0009] A crucible cover, which is detachably disposed above the crucible and is used to cover or open the opening, and is also used to place a seed crystal; and

[0010] The first heat-insulating layer is arranged in the chamber and surrounds the outer periphery of the raw material area.

[0011] In an optional embodiment, the silicon carbide single crystal growth device further includes a first isolation ring, which is disposed in the chamber and surrounds the outer circumference of the raw material zone; wherein the first isolation ring is distributed on a side of the first insulation layer away from the inner wall of the crucible.

[0012] In an optional embodiment, the silicon carbide single crystal growth device further includes a second thermal insulation layer, which is disposed in the chamber and located at the bottom of the raw material area.

[0013] In an optional embodiment, the silicon carbide single crystal growth device also includes an isolation plate and a first support ring, the first support ring is arranged in the chamber and located at the bottom of the raw material area, and the first support is distributed around the periphery of the second thermal insulation layer; the isolation plate is supported by the first support ring, and the isolation plate is located on the side of the second thermal insulation layer away from the bottom wall of the chamber.

[0014] In an optional embodiment, the silicon carbide single crystal growth device further includes a second support ring and a guide tube, wherein the second support ring is disposed in the chamber and between the raw material area and the growth area;

[0015] The guide tube is supported by the second support ring and extends toward the opening; the inner diameter of the guide tube is smaller than the inner diameter of the raw material zone.

[0016] In an optional embodiment, the silicon carbide single crystal growth device further includes a third thermal insulation layer, which is disposed on a side of the second support ring away from the raw material zone, and surrounds the outer circumference of the guide tube.

[0017] In an optional embodiment, the silicon carbide single crystal growth device also includes a second isolation ring, which is arranged in the chamber and located in the growth zone; the second isolation ring is distributed around the circumference of the guide tube, and the third insulation layer is isolated between the second isolation ring and the second support ring.

[0018] In an optional embodiment, the silicon carbide single crystal growth device further includes a filter assembly, which is disposed in the guide channel of the guide cylinder and is used to filter carbon particles.

[0019] In an optional embodiment, the filter assembly includes at least two filter plates, and the at least two filter plates are both disposed in the flow guide channel and are spaced apart along the axial direction of the flow guide channel.

[0020] In an optional embodiment, the filter assembly further includes a third support ring, at least two filter plates are connected to the third support ring, the third support ring is disposed in the guide channel, and the outer wall of the third support ring is in contact with the inner wall of the guide tube.

[0021] The beneficial effects of the silicon carbide single crystal growth device of the embodiment of the utility model include: the silicon carbide single crystal growth device provided by the embodiment of the utility model is provided with a first thermal insulation layer in the chamber of the crucible, and the first thermal insulation layer surrounds the outer periphery of the raw material zone, which is beneficial to improving the temperature dissipation and uniformity problems in the raw material zone through the provision of the thermal insulation layer, that is, it is beneficial to the thermal insulation of the raw material zone. Compared with the growth zone, the temperature of the raw material zone is higher, so as to increase the axial temperature gradient and improve the utilization rate of the raw materials, increase the crystal growth rate, and facilitate the growth of crystals with larger thickness; moreover, the higher the temperature of the raw material zone, the more beneficial it is to the carbonization rate of the silicon carbide powder, which can further improve the growth rate of the crystal and shorten the growth cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 It is a cross-sectional view of a silicon carbide single crystal growth device in an embodiment of the present utility model.

[0024] Icon: 010-silicon carbide single crystal growth device; 100-crucible; 101-raw material area; 102-growth area; 110-crucible cover; 120-seed crystal plate; 130-seed crystal; 141-first insulation layer; 142-second insulation layer; 143-third insulation layer; 151-first isolation ring; 152-isolation plate; 153-second isolation ring; 161-first support ring; 162-second support ring; 170-guide tube; 181-filter plate; 182-third support ring; 200-silicon carbide raw material. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0028] In the description of the present utility model, it should be noted that the terms "upper", "lower", "inner", "outer", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, which is only for the convenience of describing the utility model and simplifying the description, and does 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 a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0029] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "setting" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] Please refer to Figure 1 The present embodiment provides a silicon carbide single crystal growth device 010, which includes a crucible 100 and a crucible cover 110; the crucible 100 has a chamber, the chamber includes a raw material area 101 and a growth area 102 that are interconnected, the raw material area 101 is used to hold silicon carbide raw material 200, and the growth area 102 has an opening at one end away from the raw material area 101; the crucible cover 110 is detachably arranged on the crucible 100, and is used to cover or open the opening, and the crucible cover 110 is also used to set a seed crystal 130. The silicon carbide single crystal growth device 010 is used to prepare silicon carbide single crystals. During the preparation, silicon carbide powder is filled in the raw material area 101, and then the crucible cover 110 provided with a seed crystal 130 is set at the opening of the crucible 100 to cover the opening, and the crucible 100 is heated (for example: using a radio frequency furnace to cut the magnetic lines of force and the crucible 100 to make the crucible 100 heat up), so that the silicon carbide powder can be sublimated at high temperature, and the formed atmosphere (for example: Si, Si2C and SiC2) can be moved to the seed crystal 130 under the action of the temperature gradient, and then crystallized to form a silicon carbide single crystal.

[0031] Optionally, the crucible 100 and the crucible cover 110 are both made of graphite material.

[0032] Optionally, the silicon carbide single crystal growth device 010 further includes a seed crystal plate 120 , which is connected to the crucible cover 110 and is used to place a seed crystal 130 .

[0033] The manner in which the seed crystal plate 120 is disposed on the crucible cover 110 and the manner in which the seed crystal plate 120 is disposed with the seed crystal 130 are similar to the related art and will not be described in detail herein.

[0034] The silicon carbide single crystal growth device 010 of this embodiment further includes a first insulation layer 141, which is disposed in the chamber and surrounds the outer periphery of the raw material area 101. The first insulation layer 141 is disposed to improve the problem of temperature loss in the raw material area 101, that is, it is beneficial to the insulation of the raw material area 101. Compared with the growth area 102, the temperature of the raw material area 101 is higher, so as to increase the axial temperature gradient and increase the crystal growth rate (the crystal growth rate can reach at least 200-300 μm / h), which is beneficial to the growth of thicker crystals; moreover, the higher the temperature of the raw material area 101, the more beneficial it is to the carbonization rate of the silicon carbide powder, which can further increase the growth rate of the crystal and shorten the growth cycle.

[0035] Optionally, the material for preparing the first thermal insulation layer 141 includes but is not limited to hard felt, soft felt, etc., as long as it can achieve the thermal insulation effect.

[0036] Furthermore, the silicon carbide single crystal growth device 010 further includes a first isolation ring 151, which is disposed in the chamber and surrounds the outer periphery of the raw material area 101; wherein the first isolation ring 151 is distributed on the side of the first thermal insulation layer 141 away from the inner wall of the crucible 100, so that the first isolation ring 151 can separate the first thermal insulation layer 141 and the powder filled in the raw material area 101. Such an arrangement can, on the one hand, improve the problem of deformation of the first thermal insulation layer 141, and on the other hand, can use the first isolation ring 151 to block the carbon particles formed by the first thermal insulation layer 141, so as to improve the problem that the carbon particles formed by the first thermal insulation layer 141 move to the seed crystal 130 and deteriorate the quality of the grown crystal.

[0037] Optionally, the outer wall of the first insulation layer 141 fits with the inner wall of the chamber, and the inner wall of the first insulation layer 141 fits with the first isolation ring 151; such a configuration can reduce the gap between the inside and outside of the first insulation layer 141 to ensure the reliability of temperature conduction and insulation.

[0038] Optionally, the first insulation layer 141 may be connected to the inner wall of the crucible 100 by bonding, clamping, etc.; or, the first insulation layer 141 may be fixed to the inner wall of the crucible 100 by a first isolation ring 151; no specific limitation is given here.

[0039] Please continue to refer to Figure 1The silicon carbide single crystal growth device 010 of this embodiment further includes a second thermal insulation layer 142, which is disposed in the chamber and located at the bottom of the raw material area 101. The second thermal insulation layer 142 can further improve the problem of easy temperature loss in the raw material area 101, ensure the axial temperature gradient, increase the crystal growth rate, and facilitate the growth of thicker crystals.

[0040] Optionally, the preparation material of the second thermal insulation layer 142 includes but is not limited to hard felt, soft felt, etc., as long as it can achieve the thermal insulation effect.

[0041] Furthermore, the silicon carbide single crystal growth device 010 also includes an isolation plate 152 and a first support ring 161. The first support ring 161 is arranged in the chamber and located at the bottom of the raw material area 101. The first support ring 161 is distributed around the periphery of the second thermal insulation layer 142; the isolation plate 152 is supported by the first support ring 161, and the isolation plate 152 is located on the side of the second thermal insulation layer 142 away from the bottom wall of the chamber. The setting of the isolation plate 152 can isolate the powder filled in the raw material area 101 from the second thermal insulation layer 142, so as to improve the problem that the second thermal insulation layer 142 is squeezed and deformed by the powder, and the isolation plate 152 can be used to block the carbon particles formed by the second thermal insulation layer 142, so as to improve the problem that the carbon particles formed in the second thermal insulation layer 142 move to the seed crystal 130 and deteriorate the quality of the growing crystal; using the first support ring 161 to support the isolation plate 152 can effectively prevent the weight of the powder filled on the isolation plate 152 from directly acting on the second thermal insulation layer 142 below the isolation plate 152, further improving the problem that the second thermal insulation layer 142 is easily squeezed and deformed by the powder.

[0042] Furthermore, the first thermal insulation layer 141 and the first isolation ring 151 are both supported by an isolation plate 152, and the outer periphery of the isolation plate 152 is in contact with the inner wall of the chamber; on the one hand, the stability of the first thermal insulation layer 141 and the first isolation ring 151 in the chamber is ensured, and on the other hand, the isolation plate 152 is used to reliably separate the second thermal insulation layer 142 and the powder filled in the raw material area 101, which is beneficial to ensure the quality of the grown crystals.

[0043] Please refer to Figure 1The silicon carbide single crystal growth device 010 of this embodiment further includes a second support ring 162 and a guide tube 170. The second support ring 162 is disposed in the chamber and is located between the raw material area 101 and the growth area 102. The guide tube 170 is supported by the second support ring 162 and extends toward the opening. The inner diameter of the guide tube 170 is smaller than the inner diameter of the raw material area 101. Specifically, the guide tube 170 has an inlet and an outlet that are relatively distributed along its axial direction. The inlet is opposite to and connected to the raw material area 101, and the outlet is connected to the opening of the chamber. When the crucible cover 110 is disposed on the crucible 100, the seed crystal plate 120 disposed on the crucible cover 110 is relatively distributed with the outlet. The guide tube 170 is used to guide the atmosphere entering its guide channel from the inlet to flow to the outlet, and form a silicon carbide single crystal on the seed crystal 130 disposed on the seed crystal plate 120.

[0044] The inner diameter of the raw material area 101 is set to be larger than the inner diameter of the guide tube 170 to increase the filling space of the raw material area 101, so as to facilitate the filling of more silicon carbide raw materials 200. A sufficient amount of silicon carbide raw materials 200 filled in the raw material area 101 can be fully sublimated under the action of the first insulation layer 141 and the second insulation layer 142, providing sufficient Si, Si2C, SiC2 and other atmospheres for crystal growth, so as to grow large-scale and high-thickness crystals.

[0045] The manner in which the second support ring 162 is disposed in the chamber can be selected as required; illustratively, in this embodiment, the inner wall of the chamber is provided with a first step portion, and the second support ring 162 is overlapped on the first step portion.

[0046] Of course, in other embodiments, the second support ring 162 can also be disposed inside the chamber by means of snap connection, bonding, etc.

[0047] Furthermore, the silicon carbide single crystal growth device 010 further includes a third thermal insulation layer 143, which is disposed on the side of the second support ring 162 away from the raw material area 101, and the third thermal insulation layer 143 surrounds the outer periphery of the guide tube 170. The temperature of the corresponding position of the guide tube 170 covered by the third thermal insulation layer 143 is relatively high, and the atmosphere will not crystallize at the position with high temperature, so it can be ensured that the atmosphere can flow to the seed crystal 130 under the guidance of the guide tube 170.

[0048] The spacing between the second support ring 162 and the powder filled in the raw material area 101 can be selected as needed, for example: 0-30mm, specifically 0mm (i.e., the second support ring 162 is in contact with the powder), 1mm, 5mm, 10mm, 15mm, 20mm, 25mm, 30mm, etc., and is not specifically limited here.

[0049] Optionally, the thickness of the third thermal insulation layer 143 can be selected as needed, for example: 30-70 mm, etc., specifically 30 mm, 40 mm, 50 mm, 60 mm, 70 mm, etc.; no specific limitation is made here.

[0050] Of course, in other embodiments, the thickness of the third thermal insulation layer 143 can be up to 3 mm less than the total height of the guide tube 170 .

[0051] Optionally, one end of the first insulation layer 141 and the first isolation ring 151 away from the isolation plate 152 abuts against a side of the second support ring 162 facing the raw material area 101 .

[0052] Optionally, the preparation material of the third thermal insulation layer 143 includes but is not limited to hard felt, soft felt, etc., as long as it can achieve the thermal insulation effect.

[0053] Optionally, the inner wall of the third insulation layer 143 is in contact with the outer wall of the guide tube 170, and the outer wall of the third insulation layer 143 is in contact with the inner wall of the crucible 100; the gaps on both sides of the third insulation layer 143 are reduced to further ensure the insulation effect and improve the quality of the grown crystals.

[0054] Please continue to refer to Figure 1 The silicon carbide single crystal growth device 010 of this embodiment further includes a second isolation ring 153, which is disposed on the inner wall of the chamber and located in the growth zone 102; the second isolation ring 153 is distributed around the outer circumference of the guide tube 170, and the third thermal insulation layer 143 is isolated between the second isolation ring 153 and the second support ring 162. The second isolation ring 153 can protect the third thermal insulation layer 143 to improve the problem that the third protective layer is easily deformed, and the second isolation ring 153 can be used to block the carbon particles formed by the third thermal insulation layer 143 to improve the problem that the carbon particles formed by the third thermal insulation layer 143 move to the position of the seed crystal 130, resulting in the deterioration of the quality of the grown crystal.

[0055] The thickness of the second isolation ring 153 can be selected as needed, for example, 3 mm, 4 mm, 5 mm, etc., and is not specifically limited here.

[0056] Of course, in some embodiments, the thickness of the second isolation ring 153 may be flush with the end of the guide tube 170 close to the opening.

[0057] It should be noted that by adjusting the thickness of the second isolation ring 153 , the temperature field in the flow guide channel of the flow guide tube 170 can be further adjusted to improve the quality of the crystal and the growth efficiency of the crystal.

[0058] Optionally, the inner wall of the chamber is further provided with a second step portion, the second isolation ring 153 is overlapped on the second step portion, and the inner ring wall of the second isolation ring 153 is in contact with the outer wall of the guide tube 170, and the outer ring wall of the second isolation ring 153 is in contact with the inner wall of the chamber. This arrangement can ensure that the second isolation ring 153 is easy to assemble in the chamber, and ensure that the second isolation ring 153 reliably isolates the third thermal insulation layer 143.

[0059] Of course, in other embodiments, the second isolation ring 153 may also be disposed inside the chamber by means of snap connection, bonding, etc.

[0060] The atmosphere of the decomposed silicon carbide raw material 200 (for example: Si, Si2C, SiC2) will inevitably corrode the chamber to form carbon particles when it is transmitted from the raw material to the surface of the seed crystal 130. In the later stage of crystal growth, the raw material is rich in carbon and is transported to the growth zone 102 under the action of the airflow, which will form carbon inclusions in the silicon carbide single crystal. The carbon inclusions will induce defects such as microtubules, polytypes, and dislocations in the crystal, thereby reducing the physical and chemical properties of the substrate.

[0061] In order to improve the above problems, the silicon carbide single crystal growth device 010 of this embodiment further includes a filter assembly, which is disposed in the guide channel of the guide cylinder 170 to filter carbon particles and pass the atmosphere for growing crystals.

[0062] The structure of the filter assembly can be set as needed; in this embodiment, the filter assembly includes two filter plates 181, both of which are arranged in the guide channel of the guide tube 170 and are spaced apart along the axial direction of the guide channel. In this way, two filter plates 181 can be used to form two filter barriers to ensure that the atmosphere used to grow crystals passes smoothly while effectively blocking the transmission of carbon particles to the seed crystal 130, thereby improving the quality of the grown crystals.

[0063] Optionally, the materials of the two filter plates 181 can be different. For example, one filter plate 181 is a porous graphite plate, and the other filter plate 181 is a porous ceramic plate, wherein the main component of the porous ceramic plate is a high melting point metal carbide, such as tantalum carbide, etc., which is not specifically limited here. The porous graphite plate and the porous ceramic plate can both pass through the atmosphere used for crystal growth and can effectively filter carbon particles, that is, can effectively block the transmission of carbon particles to the seed crystal 130 to improve the quality of the grown crystal.

[0064] In this embodiment, the filter plate 181 near the raw material area 101 is a porous graphite plate, and the other filter plate 181 is a porous ceramic plate. Of course, in other embodiments, the filter plate 181 near the raw material area 101 is a porous ceramic plate, and the other filter plate 181 is a porous graphite plate.

[0065] It should be understood that in other embodiments, the materials of the two filter plates 181 may also be the same, for example, both are porous graphite plates, or both are porous ceramic plates, etc., which is not specifically limited here.

[0066] It should be noted that the holes in the porous graphite plate and the porous ceramic plate for allowing the atmosphere to pass through can be the pore structure of the material itself, or can be additional air holes provided in the porous graphite plate or the porous ceramic plate, and are not specifically limited here.

[0067] In other embodiments, the number of filter plates 181 may be one, three, four, etc., which is not specifically limited here.

[0068] It should be noted that, by setting at least two filter plates 181, the prepared crystals are free of carbon coating and the substrate MPD is less than 0.2 / cm 2 、Total dislocation density <2000 / cm 2 .

[0069] The way in which the filter plate 181 is arranged in the flow guide channel can be selected as needed. For example, the filter assembly further includes a third support ring 182. Both filter plates 181 are connected to the third support ring 182. The third support ring 182 is arranged in the flow guide channel, and the outer wall of the third support ring 182 is in contact with the inner wall of the flow guide tube 170. With such an arrangement, the filter plate 181 and the third support ring 182 can be assembled into one body, and then assembled in the flow guide tube 170 in a modular manner, which ensures easy assembly and is conducive to improving efficiency.

[0070] The connection method between the filter and the third support ring 182 can be selected as needed, for example: plug-in, bonding, etc., which is not specifically limited here.

[0071] The manner in which the third support ring 182 is disposed on the guide tube 170 can be selected as required. For example, the third support ring 182 is overlapped with the second support ring 162 and inserted into the guide channel from the inlet of the guide tube 170 .

[0072] Optionally, the guide tube 170 , the second isolation ring 153 , the second support ring 162 , the first isolation ring 151 , the isolation plate 152 , the first support ring 161 and the third support ring 182 are all made of graphite.

[0073] The method for growing a single crystal by the silicon carbide single crystal growth device 010 of this embodiment includes:

[0074] The second insulation layer 142, the first support ring 161, the isolation plate 152, the first insulation layer 141, and the first isolation ring 151 are assembled in the crucible 100 in sequence; then the silicon carbide raw material 200 is filled in the raw material area 101; then the second support ring 162, the filter assembly, the guide tube 170, the third insulation layer 143, and the second isolation ring 153 are assembled in the crucible 100 in sequence, and the crucible cover 110 provided with the seed crystal 130 and the seed crystal plate 120 is set in the crucible 100.

[0075] Install the silicon carbide single crystal growth device 010 in the crystal growth furnace and evacuate to 1×10 -2 mbar or below, introduce inert protective gas (for example: Ar) to a pressure of 10-50mbar, heat to 500-800°C at a heating rate of 5-20min / °C, maintain at this temperature for 5-20h, continue to heat to 1200-1700°C, maintain at this temperature for 5-20h, introduce inert gas to back-pressure to 200-900mbr, heat to 1700-2000°C at a heating rate of 1-20min / °C, maintain for 0-20h, slowly reduce the chamber pressure to 1-20mbar at 5-100mbar / h, continue to heat to 2100-2400°C at a heating rate of 1-10min / °C, the silicon carbide raw material 200 begins to sublimate to the seed crystal 130 under the action of temperature and pressure, and grows for about 150-400h before returning to pressure and cooling.

[0076] In summary, the silicon carbide single crystal growth device 010 of the present invention can increase the axial temperature gradient to improve the crystal growth rate and is conducive to growing crystals with greater thickness.

[0077] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A silicon carbide single crystal growth device, characterized in that: include: A crucible (100), the crucible (100) having a chamber, the chamber comprising a raw material area (101) and a growth area (102) which are interconnected, the raw material area (101) being used to contain silicon carbide raw material (200), and the growth area (102) having an opening at one end away from the raw material area (101); a crucible cover (110), the crucible cover (110) being detachably disposed on the crucible (100) and used to cover or open the opening, and the crucible cover (110) being further used to set a seed crystal (130); and A first thermal insulation layer (141), wherein the first thermal insulation layer (141) is disposed in the chamber and surrounds the outer periphery of the raw material area (101).

2. The silicon carbide single crystal growth device according to claim 1, characterized in that: The silicon carbide single crystal growth device also includes a first isolation ring (151), which is arranged in the chamber and surrounds the outer circumference of the raw material area (101); wherein the first isolation ring (151) is distributed on a side of the first insulation layer (141) away from the inner wall of the crucible (100).

3. The silicon carbide single crystal growth device according to claim 1, characterized in that: The silicon carbide single crystal growth device further comprises a second thermal insulation layer (142), wherein the second thermal insulation layer (142) is arranged in the chamber and located at the bottom of the raw material area (101).

4. The silicon carbide single crystal growth device according to claim 3, characterized in that: The silicon carbide single crystal growth device also includes an isolation plate (152) and a first support ring (161), wherein the first support ring (161) is arranged in the chamber and located at the bottom of the raw material area (101), and the first support ring (161) is distributed around the periphery of the second thermal insulation layer (142); the isolation plate (152) is supported by the first support ring (161), and the isolation plate (152) is located on the side of the second thermal insulation layer (142) away from the bottom wall of the chamber.

5. The silicon carbide single crystal growth device according to claim 1, characterized in that: The silicon carbide single crystal growth device further comprises a second support ring (162) and a guide tube (170); the second support ring (162) is arranged in the chamber and located between the raw material area (101) and the growth area (102); The guide tube (170) is supported by the second support ring (162), and the guide tube (170) extends toward the opening; the inner diameter of the guide tube (170) is smaller than the inner diameter of the raw material area (101).

6. The silicon carbide single crystal growth device according to claim 5, characterized in that: The silicon carbide single crystal growth device further comprises a third thermal insulation layer (143), wherein the third thermal insulation layer (143) is arranged on a side of the second support ring (162) away from the raw material area (101), and the third thermal insulation layer (143) surrounds the outer circumference of the guide tube (170).

7. The silicon carbide single crystal growth device according to claim 6, characterized in that: The silicon carbide single crystal growth device also includes a second isolation ring (153), which is arranged in the chamber and located in the growth zone (102); the second isolation ring (153) is distributed around the outer circumference of the guide tube (170), and the third insulation layer (143) is isolated between the second isolation ring (153) and the second support ring (162).

8. The silicon carbide single crystal growth device according to claim 5, characterized in that: The silicon carbide single crystal growth device also includes a filter assembly, which is arranged in the guide channel of the guide cylinder (170) and is used to filter carbon particles.

9. The silicon carbide single crystal growth device according to claim 8, characterized in that: The filter assembly comprises at least two filter plates (181), and the at least two filter plates (181) are both arranged in the guide channel and are spaced apart along the axial direction of the guide channel.

10. The silicon carbide single crystal growth device according to claim 9, characterized in that: The filter assembly further comprises a third support ring (182), at least two of the filter plates (181) are connected to the third support ring (182), the third support ring (182) is arranged in the flow guide channel, and the outer wall of the third support ring (182) is in contact with the inner wall of the flow guide tube (170).

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