Crucible cover and silicon carbide single crystal growth device

Abstract

The utility model relates to the technical field of semiconductors, in particular to a crucible cover and a silicon carbide single crystal growth device. The crucible cover comprises a middle part and an edge part, the middle part is used for installing a seed crystal, the edge part is annular and surrounds the middle part, and the inner ring side wall of the edge part is connected with the circumferential side wall of the middle part; wherein the edge part is further provided with an outer ring side wall opposite to the inner ring side wall, at least one side of the edge part is provided with a groove, and the groove is located between the inner ring side wall and the outer ring side wall. The crucible cover disclosed by the utility model can solve the problem of cracking of silicon carbide crystals tightly attached to the crucible cover, and the yield of silicon carbide single crystal growth is improved.

Description

Technical Field

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

[0002] About 50% of the cost of silicon carbide chips comes from silicon carbide substrates. Reducing the cost of silicon carbide substrates can greatly reduce the overall cost of silicon carbide chips. Among them, improving the yield of silicon carbide single crystal growth can effectively reduce the cost of silicon carbide substrates.

[0003] However, the silicon carbide single crystal growth device provided by the related technology is prone to cause cracking of the silicon carbide single crystal; wherein, during the high-temperature growth, heating and cooling process of the silicon carbide crystal, the silicon carbide seed crystal is always adhered to the crucible cover and tightly connected thereto, and the silicon carbide crystal grows on the seed crystal. Because the edge of the crucible cover is closer to the high-temperature zone during the growth and heating process, it expands more due to heat, and tensile stress is generated on the middle part of the crucible cover (i.e., the part connected to the silicon carbide seed crystal); during the cooling process, because the edge of the crucible cover is closer to the low-temperature zone, it shrinks more due to cooling, and compressive stress is generated on the middle part of the crucible cover (i.e., the part connected to the silicon carbide seed crystal). These two stresses will be transmitted to the silicon carbide crystal tightly adhered to the crucible cover, causing the crystal to crack. Especially in the high-temperature growth, heating and cooling process of large-sized crystals, the problem of crystal cracking caused by excessive crystal stress is particularly prominent. Utility Model Content

[0004] The utility model aims to provide a crucible cover and a silicon carbide single crystal growth device, wherein the crucible cover can improve the problem of cracking of silicon carbide crystals closely attached thereto and improve the yield rate of silicon carbide single crystal growth.

[0005] The embodiment of the utility model is achieved as follows:

[0006] In a first aspect, the utility model provides a crucible cover, comprising:

[0007] The middle part is used to install the seed crystal;

[0008] The edge portion is annular and arranged around the middle portion, and the inner ring side wall of the edge portion is connected to the circumferential side wall of the middle portion;

[0009] The edge portion further comprises an outer ring side wall which is arranged opposite to the inner ring side wall, and at least one side of the edge portion is provided with a groove which is located between the inner ring side wall and the outer ring side wall.

[0010] In an optional embodiment, the edge portion includes a first annular member and a second annular member, the first annular member is arranged around the middle portion, the inner annular side wall of the first annular member is connected to the circumferential side wall of the middle portion, and the second annular member is arranged around the first annular member, and the inner annular side wall of the second annular member is connected to the outer annular side wall of the first annular member;

[0011] The second annular member is used to connect with the crucible body; at least one side of the first annular member is provided with a groove, and the groove is located between the inner ring side wall of the first annular member and the outer ring side wall of the first annular member.

[0012] In an optional embodiment, the groove is a V-shaped groove or a U-shaped groove.

[0013] In an alternative embodiment, the groove is an annular groove extending around the middle portion;

[0014] The first annular member has a first side and a second side that are arranged opposite to each other, the first side of the first annular member is provided with one or more grooves, the second side of the first annular member is provided with one or more grooves, and the grooves arranged on the first side of the first annular member and the grooves arranged on the second side of the first annular member are alternately distributed in sequence along the radial direction of the middle part.

[0015] In an optional embodiment, the first annular member includes at least one deformable ring, the deformable ring includes a first side wall and a second side wall connected at an angle, and a groove located on the second side of the first annular member is formed between the first side wall and the second side wall;

[0016] The first side wall of the deformable ring closest to the middle portion surrounds the outer periphery of the middle portion; the first side wall of the deformable ring closest to the middle portion is connected to the circumferential side wall of the middle portion at an angle, and a groove located on the first side of the first annular member is formed therebetween;

[0017] The second side wall of the deformable ring closest to the second annular member is connected to the inner ring side wall of the second annular member at an angle, and a groove located on the first side of the first annular member is formed therebetween;

[0018] When there are multiple deformable rings, the multiple deformable rings are connected in sequence and distributed concentrically; in any two adjacent deformable rings, the second side wall of the deformable ring closer to the middle part is connected to the first side wall of the deformable ring farther from the middle part at an angle, and a groove located on the first side of the first ring-shaped member is formed between the two.

[0019] In an optional embodiment, at least one of the first side wall and the second side wall has a thickness of 1-5 mm; and / or,

[0020] The connection between the first side wall and the second side wall is an acute angle or an arc chamfer.

[0021] In an optional embodiment, the first annular member includes at least one deformable ring, the deformable ring includes a first side wall, a second side wall, a third side wall and a fourth side wall connected in sequence at an angle, a groove located on the first side of the first annular member is formed between the first side wall and the second side wall, and a groove located on the first side of the first annular member is formed between the second side wall, the third side wall and the fourth side wall;

[0022] The first side wall of the deformable ring closest to the middle portion surrounds the outer periphery of the middle portion and is connected to the circumferential side wall of the middle portion at an angle, the second side wall of the deformable ring closest to the middle portion surrounds the outer periphery of the middle portion at intervals, and a groove located on the second side of the first annular member is formed between the first side wall of the deformable ring closest to the middle portion, the second side wall of the deformable ring closest to the middle portion, and the circumferential side wall of the middle portion;

[0023] The fourth side wall of the deformation ring closest to the second annular member is connected to the second annular member.

[0024] In an optional embodiment, when there are multiple deformable rings, the multiple deformable rings are connected in sequence and are concentrically distributed; in any two adjacent deformable rings, the fourth side wall of the deformable ring closer to the middle portion is connected to the first side wall of the deformable ring farther from the middle portion at an angle; and / or,

[0025] The thickness of at least one of the first side wall, the second side wall, the third side wall and the fourth side wall is 1-5 mm; and / or,

[0026] The connection between the first side wall and the second side wall, the connection between the second side wall and the third side wall, and the connection between the third side wall and the fourth side wall are all at right angles.

[0027] In an optional embodiment, in the axial direction of the middle portion, the depth of the groove is H; in the radial direction of the middle portion, the width of the groove is L, and the ratio of the depth H of the groove to the width L of the groove is greater than or equal to 2.

[0028] In a second aspect, the utility model provides a silicon carbide single crystal growth device, comprising a crucible body and a crucible cover according to any one of the aforementioned embodiments, wherein an edge portion of the crucible cover is connected to the crucible body.

[0029] The beneficial effects of the crucible cover of the utility model embodiment include: the crucible cover provided by the utility model embodiment includes a middle part and an edge part, the middle part is used to install the seed crystal, the edge part is annular and is arranged around the middle part, and the inner ring side wall of the edge part is connected to the circumferential side wall of the middle part; wherein the edge part also has an outer ring side wall arranged opposite to the inner ring side wall, and at least one side of the edge part is provided with a groove, and the groove is located between the inner ring side wall and the outer ring side wall. In this way, when silicon carbide crystals are grown on the seed crystals arranged in the middle part at high temperature, even if the edge of the crucible cover is closer to the high temperature zone and expands more due to heat, since the edge portion located at the outer periphery of the middle part is provided with a groove, the edge portion will undergo adaptive deformation at high temperature, so that the tensile stress generated by the edge of the crucible cover on the middle part is released, and the stress transmitted to the crystal arranged in the middle part is reduced accordingly, which is beneficial to improving the problem of easy cracking of silicon carbide crystals during growth; similarly, in the process of cooling, even if the edge of the crucible cover is closer to the low temperature zone and shrinks more due to cooling, since the edge portion located at the outer periphery of the middle part is provided with a groove, the edge portion will undergo adaptive deformation at low temperature, so that the compressive stress generated by the edge of the crucible cover on the middle part is released, and the stress transmitted to the crystal arranged in the middle part is reduced accordingly, which is beneficial to improving the problem of easy cracking of silicon carbide crystals during growth.

[0030] The silicon carbide single crystal growth device of the embodiment of the utility model includes all the beneficial effects of the aforementioned crucible cover, for example: the stress generated at the edge of the crucible cover is released by utilizing the edge portion connected to the periphery of the middle portion, so that the stress transmitted to the seed crystal arranged in the middle portion is reduced, thereby improving the problem of easy cracking during the growth of the silicon carbide single crystal. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] 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.

[0032] Figure 1 This is a cross-sectional view of a silicon carbide single crystal growth device in an embodiment of the present utility model;

[0033] Figure 2 for Figure 1 The enlarged view of the middle II;

[0034] Figure 3 It is a partial structural schematic diagram of the crucible cover in the embodiment of the utility model;

[0035] Figure 4 This is a cross-sectional view of a silicon carbide single crystal growth device in another embodiment of the utility model;

[0036] Figure 5 This is a schematic diagram of a partial structure of a crucible cover in another embodiment of the utility model;

[0037] Figure 6 for Figure 4 The enlarged view of the middle VI;

[0038] Figure 7 It is a cross-sectional view of a silicon carbide single crystal growth device in another embodiment of the present utility model;

[0039] Figure 8 It is a partial structural schematic diagram of a crucible cover in another embodiment of the utility model;

[0040] Fig. 9 for Figure 7 Enlarged view of point IX in the middle.

[0041] Icon: 010-silicon carbide single crystal growth device; 100-crucible body; 200-crucible cover; 210-middle part; 220-edge part; 221-groove; 222-first annular member; 223-second annular member; 230-deformation ring; 231-first side wall; 232-second side wall; 233-third side wall; 234-fourth side wall; 240-overlapping part; 241-step part. DETAILED DESCRIPTION

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] Please refer to Figure 1 The present embodiment provides a silicon carbide single crystal growth device 010, which includes a crucible body 100 and a crucible cover 200 disposed on the crucible body 100; wherein the crucible body 100 is used to contain silicon carbide raw materials, the crucible cover 200 is used to set seed crystals, and the crucible cover 200 is detachably assembled to the crucible body 100. When growing a silicon carbide single crystal, the silicon carbide raw materials contained in the crucible body 100 are heated and sublimated and move to the seed crystal, and the silicon carbide single crystal can be grown on the seed crystal.

[0048] In order to improve the cracking problem of growing silicon carbide single crystals; please refer to Figure 2The crucible cover 200 of this embodiment includes a middle portion 210 and an edge portion 220. The middle portion 210 is used to set a seed crystal. For example, the seed crystal is bonded to the middle portion 210, and the grown silicon carbide crystal will be tightly attached to the middle portion 210; the edge portion 220 is connected to the outer periphery of the middle portion 210. Specifically, the edge portion 220 is annular and arranged around the middle portion 210, and the inner ring side wall of the edge portion 220 is connected to the circumferential side wall of the middle portion; wherein the edge portion 220 also has an outer ring side wall arranged opposite to the inner ring side wall, and at least one side of the edge portion is provided with a groove 221, and the groove 221 is located between the inner ring side wall and the outer ring side wall. In this way, when the silicon carbide crystal is grown on the seed crystal arranged in the middle part 210 at a high temperature, even if the edge of the crucible cover 200 is closer to the high temperature zone and expands more due to the heat, since the edge part 220 located at the outer periphery of the middle part 210 is provided with a groove 221, the edge part 220 will undergo adaptive deformation at a high temperature, so that the tensile stress generated by the edge of the crucible cover 200 on the middle part 210 is released, and the stress transmitted to the crystal arranged in the middle part 210 is reduced, which is beneficial to improve the problem that the silicon carbide crystal is easy to crack during growth; similarly, in the process of cooling, even if the edge of the crucible cover 200 is closer to the low temperature zone and shrinks more due to the cold, since the edge part 220 located at the outer periphery of the middle part 210 is provided with a groove 221, the edge part 220 will undergo adaptive deformation at a low temperature, so that the compressive stress generated by the edge of the crucible cover 200 on the middle part 210 is released, and the stress transmitted to the crystal arranged in the middle part 210 is reduced, which is beneficial to improve the problem that the silicon carbide crystal is easy to crack during growth.

[0049] Furthermore, the edge portion 220 has a first side and a second side that are arranged opposite to each other, and the first side of the edge portion 220 and the second side of the edge portion 220 are both provided with grooves 221, so that the edge portion 220 can be deformed. In this way, when the silicon carbide crystal is grown on the seed crystal arranged in the middle portion 210 at high temperature, even if the edge of the crucible cover 200 is closer to the high temperature zone and expands more due to heat, since the grooves 221 are arranged on the opposite sides of the edge portion 220 located at the periphery of the middle portion 210, the edge portion 220 will be deformed adaptively at high temperature, so that the tensile stress generated by the edge of the crucible cover 200 on the middle portion 210 is released, and the stress transmitted to the crystal arranged in the middle portion 210 is reduced, which is conducive to improving the silicon carbide crystal. Similarly, during the cooling process, even if the edge of the crucible cover 200 is closer to the low temperature zone and shrinks more due to the cooling, since grooves 221 are provided on the opposite sides of the edge portion 220 located on the periphery of the middle portion 210, the edge portion 220 will undergo adaptive deformation at low temperatures, so that the compressive stress generated by the edge of the crucible cover 200 on the middle portion 210 is released, and the stress transmitted to the crystal arranged in the middle portion 210 is reduced, which is beneficial to improving the problem of easy cracking during the growth of silicon carbide crystals.

[0050] For further information, please refer to Figure 2 and Figure 3 , a plurality of grooves 221 are disposed on the first side of the edge portion 220 and the second side of the edge portion 220, and the grooves 221 disposed on the first side of the edge portion 220 and the grooves 221 disposed on the second side of the edge portion 220 are alternately distributed in the radial direction of the middle portion 210, and each groove 221 is distributed around the circumference of the middle portion 210. Such a configuration ensures that the edge portion 220 is sensitively deformed during high temperature, heating or cooling, and then reliably releases the stress generated at the edge of the crucible cover 200, so as to reduce the stress transmitted to the middle portion 210, and improve the problem that the silicon carbide crystals generated in the middle portion 210 are easily cracked due to stress.

[0051] Optionally, the edge portion 220 includes a first annular member 222 and a second annular member 223, wherein the first annular member 222 is disposed around the middle portion 210, and the inner ring sidewall of the first annular member 222 is connected to the circumferential sidewall of the middle portion 210, and the second annular member 223 is disposed around the first annular member 222, and the inner ring sidewall of the second annular member 223 is connected to the outer ring sidewall of the first annular member 222; wherein the second annular member 223 is used to connect with the crucible body 100; a groove 221 is disposed on at least one side of the first annular member 222, and the groove 221 is located between the inner ring sidewall of the first annular member 222 and the outer ring sidewall of the first annular member 222. This arrangement ensures that after the crucible cover 200 is assembled on the crucible body 100, the deformation performance of the groove 221 is not adversely affected.

[0052] Furthermore, the groove 221 is an annular groove extending around the middle portion 210; the first annular member 222 has a first side and a second side arranged opposite to each other, the first side of the first annular member 222 is provided with one or more grooves 221, and the second side of the first annular member 222 is provided with one or more grooves 221, and the grooves 221 arranged on the first side of the first annular member 222 and the grooves 221 arranged on the second side of the first annular member 222 are alternately distributed in sequence along the radial direction of the middle portion 210.

[0053] In this embodiment, a plurality of grooves 221 are disposed on both the first side and the second side of the first annular member 222 ; of course, in other embodiments, at least one of the first side and the second side of the first annular member 222 is only disposed with one groove 221 .

[0054] The structure of the edge portion 220 can be set as needed; optionally, the first annular member 222 includes at least one deformable ring 230, the deformable ring 230 includes a first side wall 231 and a second side wall 232 connected at an angle, and a groove 221 located on the second side of the first annular member 222 is formed between the first side wall 231 and the second side wall 232; the first side wall 231 of the deformable ring 230 closest to the middle portion 210 surrounds the outer periphery of the middle portion 210; the first side wall 231 of the deformable ring 230 closest to the middle portion 210 is connected to the circumferential side wall of the middle portion 210 at an angle, and a groove 221 located on the first side of the first annular member 222 is formed between the two. Groove 221; the second side wall 232 of the deformable ring 230 closest to the second annular member 223 is connected to the inner ring side wall of the second annular member 223 at an angle, and a groove 221 located on the first side of the first annular member 222 is formed between the two; the present embodiment has a plurality of deformable rings 230, and the plurality of deformable rings 230 are connected in sequence and are concentrically distributed; of any two adjacent deformable rings 230, the second side wall 232 of the deformable ring 230 closer to the middle portion 210 is connected to the first side wall 231 of the deformable ring 230 farther from the middle portion 210 at an angle, and a groove 221 located on the first side of the first annular member 222 is formed between the two.

[0055] The first side of the edge portion 220 refers to the side of the crucible cover 200 facing the inside of the crucible body 100, and the second side of the edge portion 220 refers to the side of the crucible cover 200 facing away from the inside of the crucible body 100. With such a configuration, the groove 221 is roughly in a "V" shape, ensuring that the deformation ring 230 has a large deformation amount, which can effectively release the stress of the outer edge of the crucible cover 200, reduce the stress transmitted to the middle portion 210, and improve the problem that the silicon carbide crystals generated in the middle portion 210 are easily cracked due to stress.

[0056] Moreover, by providing a plurality of deformation rings 230, the number of grooves 221 can be increased by increasing the number of deformation rings 230, so as to ensure the deformation amount of the edge portion 220, so as to effectively release the stress on the outer edge of the crucible cover 200, reduce the stress transmitted to the middle portion 210, and improve the problem that the silicon carbide crystals generated in the middle portion 210 are easily cracked due to stress.

[0057] Exemplarily, the edge portion 220 of this embodiment includes three deformation rings 230 , which are sequentially connected and are isotropically distributed to form three grooves 221 on the second side of the edge portion 220 and four grooves 221 on the first side of the edge portion 220 .

[0058] Optionally, see Figure 4 , Figure 5 and Figure 6The connection between the first side wall 231 and the second side wall 232 is an arc chamfer; such a configuration can ensure the structural stability of the edge portion 220 and improve the problem that the edge portion 220 is easily damaged due to deformation under the action of stress.

[0059] Optionally, see Figure 2 and Figure 3 The included angle between the first side wall 231 and the second side wall 232 is an acute angle, and the specific angle may be: 20°, 30°, 45°, 60°, etc., which is not specifically limited here.

[0060] Optionally, at least one of the first side wall 231 and the second side wall 232 has a thickness of 1-5 mm, for example, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, etc., which is not specifically limited here. The first side wall 231 and the second side wall 232 are set to be thinner, so that the deformation amount of the edge portion 220 can be ensured while ensuring the structural strength of the edge portion 220, thereby preventing the edge portion 220 from being damaged due to deformation.

[0061] Exemplarily, the thickness of the first side wall 231 and the second side wall 232 of this embodiment are both 3 mm.

[0062] Optionally, see Figure 2 and Figure 3 , along the axial direction of the middle part 210, the depth of the groove 221 is H; along the radial direction of the middle part 210, the width of the groove 221 is L, and the ratio of the depth H of the groove 221 to the width L of the groove 221 is greater than or equal to 2, for example: 2, 2.1, 2.3, 2.5, 2.7, 3, etc., which are not specifically limited here. Optimizing the aspect ratio of the groove 221 so that its longitudinal depth is greater than its lateral width can ensure the deformation sensitivity of the deformation ring 230, that is, increase the deformation amount of the deformation ring 230, so as to effectively release the stress of the outer edge of the crucible cover 200, reduce the stress transmitted to the middle part 210, and improve the problem that the silicon carbide crystals generated in the middle part 210 are easily cracked under stress.

[0063] Please continue to refer to Figure 2 and Figure 3 In this embodiment, the crucible cover 200 also includes an overlapping portion 240, which is connected to the outer ring side wall of the second annular member. The overlapping portion 240 is provided with a step portion 241, and the step portion 241 overlaps and cooperates with the crucible body 100 to improve the stability of the crucible cover 200 being set on the crucible body 100; moreover, the provision of the overlapping portion 240 can improve the interference of the edge portion 220 with the crucible body 100 when the crucible cover 200 is assembled on the crucible body 100, thereby ensuring that the edge portion 220 can be reliably deformed, stress is released, and the problem of cracking of silicon carbide crystals due to large stress is improved.

[0064] Please refer to Figure 7 , Figure 8 and Fig. 9 In other embodiments, the deformation ring 230 includes a first side wall 231, a second side wall 232, a third side wall 233 and a fourth side wall 234 connected in sequence at an angle, a groove 221 located on the second side of the first annular member 222 is formed between the first side wall 231 and the second side wall 232, and a groove 221 located on the first side of the first annular member 222 is formed between the second side wall 232, the third side wall 233 and the fourth side wall 234; the first side wall 231 of the deformation ring 230 closest to the middle portion 210 surrounds the outer periphery of the middle portion 210 and is aligned with the outer periphery of the middle portion 210. The circumferential side walls of the middle portion 210 are connected at an angle, and the second side wall 232 of the deformable ring 230 closest to the middle portion 210 surrounds the outer circumference of the middle portion 210 at intervals. A groove 221 located on the second side of the first annular member 222 is formed between the first side wall 231 of the deformable ring 230 closest to the middle portion 210, the second side wall 232 of the deformable ring 230 closest to the middle portion 210, and the circumferential side wall of the middle portion 210; the fourth side wall 234 of the deformable ring 230 closest to the second annular member 223 is connected to the second annular member 223.

[0065] The first side of the edge portion 220 refers to the side of the crucible cover 200 facing the inside of the crucible body 100, and the second side of the edge portion 220 refers to the side of the crucible cover 200 facing away from the inside of the crucible body 100. In this way, the groove 221 is generally U-shaped. The edge portion 220 has more bending parts to increase the deformation of the edge portion 220, ensure that the stress of the outer edge of the crucible cover 200 is effectively released, reduce the stress transmitted to the middle portion 210, and improve the problem that the silicon carbide crystals generated in the middle portion 210 are easily cracked due to stress.

[0066] Further, the edge portion 220 includes at least two deformable rings 230, and at least two deformable rings 230 are connected in sequence and concentrically distributed, that is, when the number of deformable rings 230 is multiple, the multiple deformable rings 230 are connected in sequence and concentrically distributed; among any two adjacent deformable rings 230, the fourth side wall 234 of the deformable ring 230 closer to the middle portion 210 is connected to the first side wall 231 of the deformable ring 230 farther from the middle portion 210 at an angle, and a groove 221 located on the second side of the first annular member 222 is formed between the fourth side wall 234 of the deformable ring 230 closer to the middle portion 210, the first side wall 231 of the deformable ring 230 farther from the middle portion 210, and the second side wall 232 of the deformable ring 230 farther from the middle portion 210. By increasing the number of deformation rings 230, the number of grooves 221 can be increased, so that the deformation of the edge portion 220 can be guaranteed, so as to effectively release the stress on the outer edge of the crucible cover 200, reduce the stress transmitted to the middle portion 210, and improve the problem that the silicon carbide crystals produced in the middle portion 210 are easily cracked due to stress.

[0067] Furthermore, the fourth side wall 234 of one of the plurality of deformable rings 230 that is farthest from the middle portion 210 is connected to the second annular member 223 .

[0068] Optionally, the angle between the first side wall 231 and the second side wall 232, the angle between the second side wall 232 and the third side wall 233, and the angle between the third side wall 233 and the fourth side wall 234 can be 90°, 95°, 85°, etc., which are not specifically limited here.

[0069] Optionally, at least one of the first side wall 231, the second side wall 232, the third side wall 233 and the fourth side wall 234 has a thickness of 1-5 mm, for example, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, etc., which is not specifically limited here. The thickness of the first side wall 231, the second side wall 232, the third side wall 233 and the fourth side wall 234 is set to be relatively thin, so that the deformation amount of the edge portion 220 can be ensured while ensuring the structural strength of the edge portion 220, thereby preventing the edge portion 220 from being damaged due to deformation.

[0070] Optionally, the connection between the first side wall 231 and the second side wall 232, the connection between the second side wall 232 and the third side wall 233, and the connection between the third side wall 233 and the fourth side wall 234 are all at right angles. In other embodiments, the angle between the connection between the first side wall 231 and the second side wall 232, the connection between the second side wall 232 and the third side wall 233, and the connection between the third side wall 233 and the fourth side wall 234 can also be 88°, 93°, etc., which is not specifically limited here.

[0071] In summary, when the silicon carbide single crystal growth device 010 of the present invention grows silicon carbide crystals at high temperature, the edge of the crucible cover 200 is closer to the high temperature zone and expands more due to heat. Since grooves 221 are provided on opposite sides of the edge portion 220 located at the periphery of the middle portion 210, the edge portion 220 will undergo adaptive deformation at high temperature, so that the tensile stress generated by the edge of the crucible cover 200 on the middle portion 210 is released, and the stress transmitted to the crystal arranged in the middle portion 210 is reduced, which is beneficial to improving the problem of easy cracking of silicon carbide crystals during growth; in the process of cooling, the edge of the crucible cover 200 is closer to the low temperature zone and shrinks more due to cooling. Since grooves 221 are provided on opposite sides of the edge portion 220 located at the periphery of the middle portion 210, the edge portion 220 will undergo adaptive deformation at low temperature, so that the compressive stress generated by the edge of the crucible cover 200 on the middle portion 210 is released, and the stress transmitted to the crystal arranged in the middle portion 210 is reduced, which is beneficial to improving the problem of easy cracking of silicon carbide crystals during growth.

[0072] 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 have 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 crucible cover, characterized in that: include: A middle portion (210) for mounting a seed crystal; The edge portion (220) is annular and arranged around the middle portion (210), and the inner annular side wall of the edge portion (220) is connected to the circumferential side wall of the middle portion (210); The edge portion (220) further comprises an outer ring side wall disposed opposite to the inner ring side wall, and at least one side of the edge portion is provided with a groove (221), wherein the groove (221) is located between the inner ring side wall and the outer ring side wall.

2. The crucible cover according to claim 1, characterized in that: The edge portion (220) comprises a first annular member (222) and a second annular member (223), wherein the first annular member (222) is arranged around the middle portion (210), and an inner annular side wall of the first annular member (222) is connected to a circumferential side wall of the middle portion (210), and the second annular member (223) is arranged around the first annular member (222), and an inner annular side wall of the second annular member (223) is connected to an outer annular side wall of the first annular member (222); The second annular member (223) is used to be connected to the crucible body (100); the groove (221) is provided on at least one side of the first annular member (222), and the groove (221) is located between the inner ring side wall of the first annular member (222) and the outer ring side wall of the first annular member (222).

3. The crucible cover according to claim 2, characterized in that: The groove (221) is a V-shaped groove or a U-shaped groove.

4. The crucible cover according to claim 2, characterized in that: The groove (221) is an annular groove extending around the middle portion (210); The first annular member (222) has a first side and a second side that are arranged opposite to each other. The first side of the first annular member (222) is provided with one or more grooves (221), and the second side of the first annular member (222) is provided with one or more grooves (221). The grooves (221) arranged on the first side of the first annular member (222) and the grooves (221) arranged on the second side of the first annular member (222) are alternately distributed in sequence along the radial direction of the middle portion (210).

5. The crucible cover according to claim 4, characterized in that: The first annular member (222) comprises at least one deformable ring (230), the deformable ring (230) comprising a first side wall (231) and a second side wall (232) connected at an angle, the first side wall (231) and the second side wall (232) forming the groove (221) located on the second side of the first annular member (222); The first side wall (231) of the deformable ring (230) closest to the middle portion (210) surrounds the outer circumference of the middle portion (210); the first side wall (231) of the deformable ring (230) closest to the middle portion (210) is connected to the circumferential side wall of the middle portion (210) at an angle, and a groove (221) located on the first side of the first annular member (222) is formed therebetween; The second side wall (232) of the deformable ring (230) closest to the second annular member (223) is connected to the inner ring side wall of the second annular member (223) at an angle, and a groove (221) located on the first side of the first annular member (222) is formed therebetween; When there are multiple deformable rings (230), the multiple deformable rings (230) are connected in sequence and are concentrically distributed; in any two adjacent deformable rings (230), the second side wall (232) of the deformable ring (230) closer to the middle part (210) is connected to the first side wall (231) of the deformable ring (230) farther from the middle part (210) at an angle, and a groove (221) located on the first side of the first annular member (222) is formed between the two.

6. The crucible cover according to claim 5, characterized in that: The thickness of at least one of the first side wall (231) and the second side wall (232) is 1-5 mm; and / or, The connection between the first side wall (231) and the second side wall (232) is an acute angle or a circular chamfer.

7. The crucible cover according to claim 4, characterized in that: The first annular member (222) comprises at least one deformable ring (230), the deformable ring (230) comprising a first side wall (231), a second side wall (232), a third side wall (233) and a fourth side wall (234) which are sequentially connected at an angle, and the groove (221) located on the first side of the first annular member (222) is formed between the second side wall (232), the third side wall (233) and the fourth side wall (234); The first side wall (231) of the deformable ring (230) closest to the middle portion (210) surrounds the outer periphery of the middle portion (210) and is connected to the circumferential side wall of the middle portion (210) at an angle; the second side wall (232) of the deformable ring (230) closest to the middle portion (210) surrounds the outer periphery of the middle portion (210) at intervals; a groove (221) located on the second side of the first annular member (222) is formed between the first side wall (231) of the deformable ring (230) closest to the middle portion (210), the second side wall (232) of the deformable ring (230) closest to the middle portion (210), and the circumferential side wall of the middle portion (210); The fourth side wall (234) of the deformation ring (230) closest to the second annular member (223) is connected to the second annular member (223); When there are multiple deformable rings (230), the multiple deformable rings (230) are connected in sequence and are concentrically distributed; in any two adjacent deformable rings (230), the fourth side wall (234) of the deformable ring (230) closer to the middle portion (210) is connected to the first side wall (231) of the deformable ring (230) farther from the middle portion (210) at an angle.

8. The crucible cover according to claim 7, characterized in that: The thickness of at least one of the first side wall (231), the second side wall (232), the third side wall (233) and the fourth side wall (234) is 1-5 mm; and / or, The connection between the first side wall (231) and the second side wall (232), the connection between the second side wall (232) and the third side wall (233), and the connection between the third side wall (233) and the fourth side wall (234) are all at right angles.

9. The crucible cover according to any one of claims 1 to 8, characterized in that: In the axial direction of the middle portion (210), the depth of the groove (221) is H; in the radial direction of the middle portion (210), the width of the groove (221) is L, and the ratio of the depth H of the groove (221) to the width L of the groove (221) is greater than or equal to 2.

10. A silicon carbide single crystal growth device, characterized in that: It comprises a crucible body (100) and the crucible cover according to any one of claims 1 to 9, wherein an edge portion (220) of the crucible cover is connected to the crucible body (100).

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