Crucible for growth of large-size silicon carbide single crystals and use method of crucible

Abstract

The invention discloses a crucible for large-size silicon carbide single crystal growth and a use method thereof, and relates to the technical field of artificial crystal growth. The crucible for growth of the large-size silicon carbide single crystals comprises a crucible body, a crystal growth cover and a material preparation bin, the crucible body is covered with the crystal growing cover, a crystal growing table is arranged on the inner top surface of the crystal growing cover, the crystal growing cover is provided with a wing plate, the wing plate is movably arranged between the material preparation bin and the crucible body, a discharging port is formed in the bottom of the material preparation bin, a material passing port is formed in the wing plate, the discharging port and the material passing port are arranged in a staggered mode, and the crystal growing cover is used for driving the wing plate to move to a preset position. And the material passing opening is communicated with the discharging opening. Compared with the prior art, the crucible for growth of the large-size silicon carbide single crystals, provided by the invention, has the advantages that the material passing holes formed in the wing plates and the material outlet formed in the bottom of the material preparation bin are adopted, so that material supplementation can be performed in the growth process of the silicon carbide single crystals, and the sublimation amount of silicon carbide polycrystalline powder is increased; large-size silicon carbide single crystal growth is realized, and customer requirements are met.

Description

Technical Field

[0001] The present invention relates to the technical field of artificial crystal growth, and in particular to a crucible for growing a large-sized silicon carbide single crystal and a method for using the crucible. Background Art

[0002] At present, the physical vapor transport (PVT) method of silicon carbide single crystal growth technology is to place silicon carbide polycrystalline raw materials in a closed cavity formed by a graphite crucible and a crucible cover in a vacuum environment or an inert atmosphere, and bond the silicon carbide seed crystal to the inner wall of the crucible cover, and heat the silicon carbide polycrystalline raw materials at the bottom of the graphite crucible and sublimate it, thereby growing silicon carbide single crystals on the silicon carbide seed crystals. However, the current loading amount of the graphite crucible is small, and the height of the silicon carbide single crystal growth is small, so it is impossible to grow large-sized silicon carbide single crystals on the silicon carbide seed crystals, resulting in limited product size and failure to meet customer needs.

[0003] In view of this, it is particularly important to design a large-sized crucible for growing silicon carbide single crystals that can be replenished and a method for using the crucible, especially in the growth of silicon carbide single crystals. Summary of the invention

[0004] The purpose of the present invention is to provide a crucible for growing large-sized silicon carbide single crystals, which can be replenished during the growth process of silicon carbide single crystals to increase the sublimation amount of silicon carbide polycrystalline powder, achieve large-sized silicon carbide single crystal growth, and meet customer needs.

[0005] Another object of the present invention is to provide a method for using a crucible for growing large-sized silicon carbide single crystals, which can replenish material during the growth process of silicon carbide single crystals to increase the sublimation amount of silicon carbide polycrystalline powder, achieve large-sized silicon carbide single crystal growth, and meet customer needs.

[0006] The present invention is achieved by adopting the following technical solutions.

[0007] A large-sized crucible for growing silicon carbide single crystals comprises a crucible body, a crystal growth cover and a material preparation bin. The crystal growth cover is arranged on the crucible body. A crystal growth table is arranged on the inner top surface of the crystal growth cover. The crystal growth table is used for bonding silicon carbide seed wafers. The crucible body is used for containing silicon carbide polycrystalline powder and sublimating it when heated, so as to grow silicon carbide single crystals on the silicon carbide seed wafers. The crystal growth cover is provided with a wing plate, which is movably arranged between the material preparation bin and the crucible body. The material preparation bin is used for containing silicon carbide polycrystalline powder. A discharge port is provided at the bottom of the material preparation bin. A feeding port is provided on the wing plate. The discharge port and the feeding port are staggered. The crystal growth cover is used for driving the wing plate to move to a preset position so that the feeding port is connected with the discharge port, so that the silicon carbide polycrystalline powder in the material preparation bin flows to the crucible body.

[0008] Optionally, the material preparation bin is in an annular shape, a clearance hole is provided in the middle of the material preparation bin, the crystal growth cover is circular, the crystal growth cover is coaxially arranged with the material preparation bin, the crystal growth cover passes through the clearance hole, and partially extends into the crucible body, and the crystal growth cover rotates in cooperation with the clearance hole.

[0009] Optionally, the material preparation bin includes an outer peripheral wall, a bottom wall and a cover plate, the outer peripheral wall is arranged outside the bottom wall and is connected to the bottom wall, a make way hole is opened in the middle of the bottom wall, the outer peripheral wall, the bottom wall and the crystal growth cover together form an annular cavity, the annular cavity is used to hold silicon carbide polycrystalline powder, the cover plate is arranged outside the annular cavity, the wing plate is fitted under the bottom wall, and the discharge port is opened on the bottom wall.

[0010] Optionally, there are multiple discharge ports and feed ports, and the multiple discharge ports are arranged on the bottom wall in a circular array with the clearance hole as the center, and each feed port is selectively connected to a discharge port.

[0011] Optionally, a limit support ring is provided on the top of the crucible body, the wing plate is in a circular ring shape, the wing plate is overlapped on the limit support ring, and is rotatably matched with the limit support ring, and the limit support ring is staggered with the feeding port.

[0012] Optionally, a groove is provided on the top of the crucible body, and a boss is provided on the bottom of the material preparation bin, and the boss cooperates with the groove.

[0013] Optionally, the crucible for growing large-size silicon carbide single crystals further comprises a material rake, which is connected to the bottom of the crystal growth cover and arranged between the crystal growth cover and the crucible body, and the material rake is extended radially along the crucible body.

[0014] Optionally, there are multiple material-dispensing rakes, which are distributed in a circular array; and / or, the position of the material-dispensing rake corresponds to the position of the material-passing port.

[0015] Optionally, an upper shaft is provided on the top of the crystal growth cover, and the upper shaft is used for manual rotation or connection with a driving motor.

[0016] A method for using a crucible for growing a large-sized silicon carbide single crystal is applied to the above-mentioned crucible for growing a large-sized silicon carbide single crystal. The method for using the crucible for growing a large-sized silicon carbide single crystal comprises: bonding a silicon carbide seed crystal wafer on a crystal growth table, and filling the crucible body with silicon carbide polycrystalline powder; assembling the crucible body, a crystal growth cover and a material preparation bin, and then filling the material preparation bin with silicon carbide polycrystalline powder; heating the crucible body to sublime the silicon carbide polycrystalline powder therein, thereby growing a silicon carbide single crystal on the silicon carbide seed crystal wafer; and using the crystal growth cover to drive a wing plate to move to a preset position, so that a material inlet is connected to a material outlet, thereby allowing the silicon carbide polycrystalline powder in the material preparation bin to flow to the crucible body.

[0017] The large-size crucible for growing silicon carbide single crystals and the use method thereof provided by the present invention have the following beneficial effects: The present invention provides a large-sized crucible for growing silicon carbide single crystals. The crystal growth cover is arranged on the crucible body. The inner top surface of the crystal growth cover is provided with a crystal growth table, which is used for bonding silicon carbide seed wafers. The crucible body is used for containing silicon carbide polycrystalline powder and sublimating it when heated, so as to grow silicon carbide single crystals on the silicon carbide seed wafers. The crystal growth cover is provided with a wing plate, which is movably arranged between a material preparation bin and the crucible body. The material preparation bin is used for containing silicon carbide polycrystalline powder. A discharge port is provided at the bottom of the material preparation bin, and a feeding port is provided on the wing plate. The discharge port and the feeding port are staggered. The crystal growth cover is used for driving the wing plate to move to a preset position so that the feeding port is connected with the discharge port, so that the silicon carbide polycrystalline powder in the material preparation bin flows to the crucible body. Compared with the prior art, the crucible for growing large-sized silicon carbide single crystals provided by the present invention adopts a feed port opened on the wing plate and a discharge port opened at the bottom of the preparation bin. Therefore, it is possible to replenish materials during the growth process of silicon carbide single crystals to increase the sublimation amount of silicon carbide polycrystalline powder, thereby achieving the growth of large-sized silicon carbide single crystals and meeting customer needs.

[0018] At the same time, the wing plate is movably arranged between the material preparation bin and the crucible body, that is, the material preparation bin is arranged above the crucible body. During the growth process of the silicon carbide single crystal, the crucible body needs to be heated to sublimate the silicon carbide polycrystalline powder in the crucible body, so as to realize the function of growing the silicon carbide single crystal on the silicon carbide seed wafer. During this process, part of the heat will be transferred to the material preparation bin to preheat the silicon carbide polycrystalline powder in the material preparation bin, which effectively improves the heat utilization rate, and the preheated silicon carbide polycrystalline powder can be quickly sublimated after being added into the crucible body, which improves the growth rate of the silicon carbide single crystal and improves the production efficiency.

[0019] The method for using a large-sized crucible for growing a silicon carbide single crystal provided by the present invention is applied to the crucible for growing a large-sized silicon carbide single crystal, and can replenish materials during the growth process of the silicon carbide single crystal to increase the sublimation amount of silicon carbide polycrystalline powder, thereby achieving the growth of large-sized silicon carbide single crystals and meeting customer needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 A cross-sectional view of a large-sized crucible for growing silicon carbide single crystals provided by an embodiment of the present invention; Figure 2 A cross-sectional view of a material preparation bin in a crucible for growing a large-sized silicon carbide single crystal provided by an embodiment of the present invention; Figure 3 A cross-sectional view of a crucible body in a large-sized crucible for growing a silicon carbide single crystal provided by an embodiment of the present invention; Figure 4 A cross-sectional view of a crystal growth cover in a crucible for growing a large-sized silicon carbide single crystal provided by an embodiment of the present invention.

[0022] Icons: 100-crucible for growing large-sized silicon carbide single crystals; 110-crucible body; 111-limiting support ring; 112-groove; 120-crystal growth cover; 121-crystal growth table; 122-wing plate; 123-feeding port; 124-upper shaft; 130-material preparation bin; 131-discharging port; 132-clearance hole; 133-peripheral wall; 134-bottom wall; 135-cover plate; 136-annular cavity; 137-boss; 140-material rake. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0024] 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 invention claimed for protection, 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.

[0025] 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.

[0026] In the description of the present invention, it should be noted that the terms "inside", "outside", "upper", "lower", "horizontal", 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 invented product is usually placed when in use, which is only for the convenience of describing the present invention 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 limiting the present invention. 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.

[0027] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "connect", "install", and "connect" 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 indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the features of the following embodiments can be combined with each other.

[0029] Please refer to Figures 1 to 4 The embodiment of the present invention provides a large-sized silicon carbide single crystal growth crucible 100 for growing silicon carbide single crystals. It can replenish materials during the growth of silicon carbide single crystals to increase the sublimation amount of silicon carbide polycrystalline powder, achieve large-sized silicon carbide single crystal growth, and meet customer needs.

[0030] The crucible 100 for growing a large-sized silicon carbide single crystal includes a crucible body 110, a crystal growth cover 120, and a material preparation bin 130. The crystal growth cover 120 is arranged on the crucible body 110, and a crystal growth platform 121 is arranged on the inner top surface of the crystal growth cover 120, and the crystal growth platform 121 is used to bond a silicon carbide seed wafer. The crystal growth cover 120 is connected to the crucible body 110, and the crucible body 110 is used to contain silicon carbide polycrystalline powder and sublimate it when heated. The sublimated gaseous silicon carbide polycrystalline raw material can smoothly enter the crystal growth cover 120, and grow a silicon carbide single crystal on the silicon carbide seed wafer bonded to the crystal growth platform 121, thereby realizing the silicon carbide single crystal growth function.

[0031] It should be noted that the crystal growth cover 120 is provided with a wing plate 122, which is movably arranged between the material preparation bin 130 and the crucible body 110, and the wing plate 122 can move relative to the material preparation bin 130 and the crucible body 110. The material preparation bin 130 is used to contain silicon carbide polycrystalline powder, and a discharge port 131 is provided at the bottom of the material preparation bin 130, and a feeding port 123 is provided on the wing plate 122. The discharge port 131 and the feeding port 123 are staggered, that is, the discharge port 131 and the feeding port 123 are not connected under normal conditions, and the silicon carbide polycrystalline powder in the material preparation bin 130 will not flow into the crucible body 110. Furthermore, during the growth of the silicon carbide single crystal, when the silicon carbide polycrystalline powder in the crucible body 110 is consumed to a first preset volume and needs to be replenished, the crystal growth cover 120 drives the wing plate 122 to move to a preset position so that the feed port 123 is connected to the discharge port 131, so that the silicon carbide polycrystalline powder in the preparation bin 130 flows to the crucible body 110, thereby realizing the replenishment function; optionally, the movement process of the crystal growth cover 120 driving the wing plate 122 can be continuous rotation, so that the feed port 123 and the discharge port 131 are connected. Intermittently connected, so that the silicon carbide polycrystalline powder in the preparation bin 130 flows to the crucible body 110, realizing the feeding function; when the silicon carbide polycrystalline powder in the crucible body 110 reaches the second preset volume, the crystal growth cover 120 drives the wing plate 122 to reset, so that the feeding port 123 and the discharge port 131 are staggered, and the silicon carbide polycrystalline powder in the preparation bin 130 will not flow into the crucible body 110; this cycle is repeated until the silicon carbide single crystal grown on the silicon carbide seed wafer reaches a preset height. In this way, during the growth process of the silicon carbide single crystal, the material can be continuously fed to increase the sublimation amount of the silicon carbide polycrystalline powder, realize the growth of large-sized silicon carbide single crystals, and meet customer needs.

[0032] Furthermore, the material preparation bin 130 is in a circular shape, and a clearance hole 132 is provided in the middle of the material preparation bin 130. The crystal growth cover 120 is circular, and the crystal growth cover 120 and the material preparation bin 130 are coaxially arranged. The crystal growth cover 120 passes through the clearance hole 132 and partially extends into the crucible body 110. The crystal growth cover 120 and the clearance hole 132 are rotatably matched, and the crystal growth cover 120 can rotate in the clearance hole 132. The material preparation bin 130 can limit the crystal growth cover 120 through the side wall of the clearance hole 132 to ensure that the crystal growth cover 120 rotates around its axis. Specifically, the wing plate 122 is connected to the outer circumference of the crystal growth cover 120. When the crystal growth cover 120 rotates relative to the clearance hole 132, the wing plate 122 will also rotate accordingly, so that the feeding port 123 on the wing plate 122 is selectively connected to the discharge port 131 at the bottom of the preparation bin 130, thereby realizing the feeding function and the feeding suspension function.

[0033] In this embodiment, the crystal growth cover 120 drives the wing plate 122 to move by rotating, so that the material inlet 123 is selectively connected with the material outlet 131, thereby realizing the material replenishment function.

[0034] It is worth noting that, compared with the technical solution of setting a material bin outside the crucible and replenishing materials through a complex structure such as a spiral feeding structure in the prior art (complex structure and high cost), the present invention optimizes the crucible structure, sets a material preparation bin 130 on the upper side of the crucible body 110, and drives the crystal growth cover 120 to rotate. On the one hand, it can drive the silicon carbide seed crystal to rotate to facilitate crystal growth, and on the other hand, it can realize the replenishment of silicon carbide polycrystalline powder, cancel the setting of the material conveying related structure, simplify the entire single crystal growth system, and reduce the equipment cost. Furthermore, by controlling the misalignment or connection between the material port 123 and the discharge port 131, the adjustment of the replenishment rate can be realized simply and reliably, without the need to set up complex valves and other adjustment mechanisms, further simplifying the entire single crystal growth system and reducing the equipment cost.

[0035] The material preparation bin 130 includes an outer peripheral wall 133, a bottom wall 134 and a cover plate 135. The outer peripheral wall 133 is arranged outside the bottom wall 134 and connected to the bottom wall 134. A clearance hole 132 is opened in the middle of the bottom wall 134. The outer peripheral wall 133, the bottom wall 134 and the crystal growth cover 120 together form an annular cavity 136. The annular cavity 136 is used to hold silicon carbide polycrystalline powder to achieve storage and preparation of silicon carbide polycrystalline powder. The cover plate 135 is arranged outside the annular cavity 136 to seal the annular cavity 136 to prevent external air from entering the crucible body 110 through the annular cavity 136, thereby ensuring the stability of the growth of silicon carbide single crystals. Specifically, the wing plate 122 is fitted under the bottom wall 134 , the discharge port 131 is opened on the bottom wall 134 , and the wing plate 122 can rotate relative to the bottom wall 134 driven by the crystal growth cover 120 so that the material passage port 123 thereon is selectively connected with the discharge port 131 .

[0036] Preferably, there are multiple discharge ports 131 and multiple feed ports 123, and the multiple discharge ports 131 are arranged on the bottom wall 134 in a circular array with the give way hole 132 as the center, and each feed port 123 is selectively connected to a discharge port 131. The multiple discharge ports 131 and the multiple feed ports 123 work together to increase the speed at which the silicon carbide polycrystalline powder in the annular cavity 136 flows to the crucible body 110, thereby improving the feeding efficiency, achieving rapid feeding, and further improving the growth efficiency of silicon carbide single crystals.

[0037] In this embodiment, the number of discharge ports 131 and the number of feed ports 123 are both four, but this is not limited to this. In other embodiments, the number of discharge ports 131 and the number of feed ports 123 can be both two or both six. There is no specific limitation on the number of discharge ports 131 and the number of feed ports 123.

[0038] It is worth noting that a limit ring 111 is provided on the top of the crucible body 110, and the wing plate 122 is in a circular ring shape. The wing plate 122 is overlapped on the limit ring 111 and is rotatably matched with the limit ring 111, that is, the wing plate 122 is rotatably provided between the bottom wall 134 and the limit ring 111, and the wing plate 122 can rotate relative to the limit ring 111 under the drive of the crystal growth cover 120, and the limit ring 111 is used to support and limit the wing plate 122 to ensure the stability of the rotation of the wing plate 122. Specifically, the limit ring 111 is staggered with the feeding port 123 to prevent the silicon carbide polycrystalline powder flowing down from the feeding port 123 from being blocked by the limit ring 111 and unable to fall into the crucible body 110, thereby ensuring the reliability of the feeding.

[0039] In this embodiment, a groove 112 is provided on the top of the crucible body 110, and a boss 137 is provided on the bottom of the material preparation bin 130. The boss 137 cooperates with the groove 112 to fix the relative positions of the material preparation bin 130 and the crucible body 110, thereby preventing the material preparation bin 130 from moving along with the crystal growth cover 120 during the rotation of the crystal growth cover 120, thereby ensuring the structural stability of the entire large-size silicon carbide single crystal growth crucible 100 and improving the silicon carbide single crystal growth effect.

[0040] Preferably, the crucible 100 for growing large-sized silicon carbide single crystals further includes a material rake 140. The material rake 140 is connected to the bottom of the crystal growth cover 120 and is disposed between the crystal growth cover 120 and the crucible body 110. The material rake 140 is disposed to extend radially along the crucible body 110. The material rake 140 is used to rake flat the silicon carbide polycrystalline powder added into the crucible body 110 to ensure uniform heating of the silicon carbide polycrystalline powder in the crucible body 110, thereby improving the growth effect of the silicon carbide single crystal.

[0041] Furthermore, there are multiple material rakes 140, which are distributed in a ring array, and the multiple material rakes 140 work together to improve the raking effect. In this embodiment, the number of material rakes 140 is four, but it is not limited to this. In other embodiments, the number of material rakes 140 can be two or six, and the number of material rakes 140 is not specifically limited.

[0042] Preferably, the position of the material rake 140 corresponds to the position of the feed port 123. During the rotation of the crystal growth cover 120, the silicon carbide polycrystalline powder in the annular cavity 136 flows into the crucible body 110 through the discharge port 131 and the feed port 123 in sequence. At the same time, the material rake 140 levels the silicon carbide polycrystalline powder flowing into the crucible body 110, so that the silicon carbide polycrystalline powder in the crucible body 110 is in a flat state, thereby ensuring the growth effect of the silicon carbide single crystal.

[0043] It is worth noting that during the growth of silicon carbide single crystals, the edge of the crucible body 110 is heated to a higher temperature, while the middle part is heated to a lower temperature, which makes the edge of the silicon carbide polycrystalline powder in the crucible body 110 sublime faster, while the middle part sublimates slower. Therefore, it is necessary to supplement the edge of the crucible body 110. In the present invention, the positions corresponding to the discharge port 131 and the feed port 123 and the position of the material rake 140 are all located at the edge of the crucible body 110 to achieve the functions of supplementing and raking the edge of the crucible body 110, and the supplement effect is good. Furthermore, when the silicon carbide polycrystalline powder in the crucible body 110 is sublimated, the silicon element sublimates more than the carbon element. Therefore, the proportion of silicon element in the silicon carbide polycrystalline powder in the preparation bin 130 is greater than the proportion of carbon element, so as to improve the supplement balance effect.

[0044] Preferably, an upper shaft 124 is provided at the top of the crystal growth cover 120, and the upper shaft 124 is coaxially arranged with the material preparation bin 130. The upper shaft 124 is used for manual rotation or connected to a driving motor to drive the entire crystal growth cover 120 to rotate, thereby realizing the material feeding function, the material feeding suspension function and the raking function.

[0045] The embodiment of the present invention further provides a method for using a large-sized crucible for growing a silicon carbide single crystal. The method for using a large-sized crucible for growing a silicon carbide single crystal comprises the following steps: Step S110 : bonding a silicon carbide seed wafer to the crystal growth table 121 , and filling the crucible body 110 with silicon carbide polycrystalline powder.

[0046] Step S120 : assembling the crucible body 110 , the crystal growth cover 120 and the material preparation bin 130 , and then filling the material preparation bin 130 with silicon carbide polycrystalline powder.

[0047] It should be noted that, in step S120, the crystal growth cover 120 is first inserted into the crucible body 110 so that the wing plate 122 overlaps the limiting support ring 111 of the crucible body 110, so that the wing plate 122 and the limiting support ring 111 are rotatably matched; then the bottom wall 134 of the material preparation bin 130 is sleeved on the outside of the crystal growth cover 120, so that the wing plate 122 is arranged between the bottom wall 134 and the limiting support ring 111, and the boss 137 is matched with the groove 112 to fix the relative position of the material preparation bin 130 and the crucible body 110; then, silicon carbide polycrystalline powder is filled into the material preparation bin 130; then the cover plate 135 is covered on the outer peripheral wall 133 to close the annular cavity 136, and the assembly of the crucible body 110, the crystal growth cover 120 and the material preparation bin 130 is completed.

[0048] Step S130: heating the crucible body 110 to sublime the silicon carbide polycrystalline powder therein, thereby growing a silicon carbide single crystal on the silicon carbide seed wafer.

[0049] Step S140 : using the crystal growth cover 120 to drive the wing plate 122 to move to a preset position, so that the material inlet 123 is connected to the material outlet 131 , thereby allowing the silicon carbide polycrystalline powder in the material preparation bin 130 to flow into the crucible body 110 .

[0050] It should be noted that in step S140, the crucible body 110 is replenished with material according to the demand. In the process of the crystal growth cover 120 driving the wing plate 122 to rotate, the replenishment amount is controlled by controlling the rotation speed and number of revolutions of the crystal growth cover 120 so that the replenishment amount reaches the demand. In this process, the material rake 140 rotates with the crystal growth cover 120 to rake the silicon carbide polycrystalline powder replenished into the crucible body 110 flat, so that the silicon carbide polycrystalline powder in the crucible body 110 is always in a flat state, thereby ensuring the growth effect of silicon carbide single crystals.

[0051] The crucible 100 for growing a large-sized silicon carbide single crystal provided in an embodiment of the present invention comprises a crystal growth cover 120 which is arranged on a crucible body 110, a crystal growth platform 121 is arranged on the inner top surface of the crystal growth cover 120, and the crystal growth platform 121 is used for bonding a silicon carbide seed wafer, and the crucible body 110 is used for containing silicon carbide polycrystalline powder and sublimating it when heated, so as to grow a silicon carbide single crystal on the silicon carbide seed wafer, and the crystal growth cover 120 is provided with a wing plate 122, and the wing plate 122 is movably arranged on the material preparation Between the bin 130 and the crucible body 110, the preparation bin 130 is used to hold silicon carbide polycrystalline powder, a discharge port 131 is provided at the bottom of the preparation bin 130, a feeding port 123 is provided on the wing plate 122, the discharge port 131 and the feeding port 123 are staggered, and the crystal growth cover 120 is used to drive the wing plate 122 to move to a preset position so that the feeding port 123 is connected with the discharge port 131, so that the silicon carbide polycrystalline powder in the preparation bin 130 flows to the crucible body 110. Compared with the prior art, the crucible 100 for growing a large-sized silicon carbide single crystal provided by the present invention adopts the feeding port 123 provided on the wing plate 122 and the discharge port 131 provided at the bottom of the preparation bin 130, so that the material can be supplemented during the growth process of the silicon carbide single crystal to increase the sublimation amount of the silicon carbide polycrystalline powder, realize the growth of a large-sized silicon carbide single crystal, and meet the needs of customers. The method for using the crucible for growing a large-sized silicon carbide single crystal is simple in steps and has high production efficiency.

[0052] At the same time, the wing plate 122 is movably arranged between the material preparation bin 130 and the crucible body 110, that is, the material preparation bin 130 is arranged above the crucible body 110. During the growth process of the silicon carbide single crystal, the crucible body 110 needs to be heated to allow the silicon carbide polycrystalline powder in the crucible body 110 to sublime, thereby realizing the function of growing silicon carbide single crystals on the silicon carbide seed wafer. During this process, part of the heat will be transferred to the material preparation bin 130 to preheat the silicon carbide polycrystalline powder in the material preparation bin 130, thereby effectively improving the heat utilization rate, and the preheated silicon carbide polycrystalline powder can be quickly sublimated after being added into the crucible body 110, thereby improving the growth rate of the silicon carbide single crystal and improving production efficiency.

[0053] 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 for growing large-sized silicon carbide single crystals, characterized in that: The invention comprises a crucible body, a crystal growth cover and a material preparation bin, wherein the crystal growth cover is arranged on the crucible body, the inner top surface of the crystal growth cover is provided with a crystal growth table, the crystal growth table is used for bonding silicon carbide seed wafers, the crucible body is used for containing silicon carbide polycrystalline powder and making it sublime when heated, so as to grow silicon carbide single crystals on the silicon carbide seed wafers, the crystal growth cover is provided with a wing plate, the wing plate is movably arranged between the material preparation bin and the crucible body, the material preparation bin is used for containing silicon carbide polycrystalline powder, the bottom of the material preparation bin is provided with a discharge port, the wing plate is provided with a feeding port, the discharge port and the feeding port are staggered, the crystal growth cover is used for driving the wing plate to move to a preset position, so that the feeding port is connected with the discharge port, so that the silicon carbide polycrystalline powder in the material preparation bin flows to the crucible body.

2. The crucible for growing a large-sized silicon carbide single crystal according to claim 1, characterized in that: The material preparation bin is in a ring shape, a clearance hole is arranged in the middle of the material preparation bin, the crystal growth cover is in a circle, the crystal growth cover is coaxially arranged with the material preparation bin, the crystal growth cover passes through the clearance hole, and partially extends into the crucible body, and the crystal growth cover is rotatably matched with the clearance hole.

3. The crucible for growing a large-sized silicon carbide single crystal according to claim 2, characterized in that: The material preparation bin includes an outer peripheral wall, a bottom wall and a cover plate. The outer peripheral wall is arranged outside the bottom wall and is connected to the bottom wall. The middle part of the bottom wall is provided with the make way hole. The outer peripheral wall, the bottom wall and the crystal growth cover together form an annular cavity. The annular cavity is used to hold silicon carbide polycrystalline powder. The cover plate is arranged outside the annular cavity. The wing plate is fitted under the bottom wall. The discharge port is opened on the bottom wall.

4. The crucible for growing a large-sized silicon carbide single crystal according to claim 3, characterized in that: There are multiple discharge ports and multiple feed ports, and the multiple discharge ports are arranged on the bottom wall in a circular array with the clearance hole as the center, and each feed port is selectively connected to one discharge port.

5. The crucible for growing a large-sized silicon carbide single crystal according to claim 1, characterized in that: A limit support ring is arranged on the top of the crucible body, the wing plate is in a circular ring shape, the wing plate is overlapped on the limit support ring and rotatably matched with the limit support ring, and the limit support ring is staggered with the material passing port.

6. The crucible for growing a large-sized silicon carbide single crystal according to claim 1, characterized in that: A groove is formed on the top of the crucible body, and a boss is formed on the bottom of the material preparation bin, and the boss matches the groove.

7. The crucible for growing a large-sized silicon carbide single crystal according to claim 1, characterized in that: The crucible for growing large-size silicon carbide single crystals further comprises a material rake, which is connected to the bottom of the crystal growth cover and arranged between the crystal growth cover and the crucible body, and the material rake is extended radially along the crucible body.

8. The crucible for growing a large-sized silicon carbide single crystal according to claim 7, characterized in that: There are multiple material-dispensing rakes, and the multiple material-dispensing rakes are distributed in a ring array; And / or, the position of the material rake corresponds to the position of the material passing port.

9. The crucible for growing a large-sized silicon carbide single crystal according to claim 1, characterized in that: An upper shaft is arranged on the top of the crystal growth cover, and the upper shaft is used for manual rotation or connection with a driving motor.

10. A method for using a crucible for growing a large-sized silicon carbide single crystal, characterized in that: Applicable to the large-sized crucible for growing silicon carbide single crystals as claimed in any one of claims 1 to 9, the method for using the large-sized crucible for growing silicon carbide single crystals comprises: Bonding a silicon carbide seed wafer on the crystal growth table, and filling the crucible body with silicon carbide polycrystalline powder; Assembling the crucible body, the crystal growth cover and the material preparation bin, and then filling the material preparation bin with silicon carbide polycrystalline powder; The crucible body is heated to sublime the silicon carbide polycrystalline powder therein, thereby growing a silicon carbide single crystal on the silicon carbide seed wafer; The crystal growth cover is used to drive the wing plate to move to a preset position so that the material inlet is connected to the material outlet, thereby allowing the silicon carbide polycrystalline powder in the material preparation bin to flow to the crucible body.

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