Crucible for growing large-size silicon carbide single crystals and method of using the same

Abstract

The present invention discloses a crucible for growing large-sized silicon carbide single crystals and a method for using the same, and relates to the technical field of artificial crystal growth. The 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, the inner top surface of the crystal growth cover is provided with a crystal growth table, 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, a discharge port is provided at the bottom of the material preparation bin, the wing plate is provided with a feed port, the discharge port and the feed port are staggered, and the crystal growth cover is used to drive the wing plate to move to a preset position so that the feed port and the discharge port are connected. Compared with the prior art, the large-sized crucible for growing silicon carbide single crystals provided by the present invention adopts a feed port provided on the wing plate and a discharge port provided at the bottom of the material preparation bin, so that feeding can be performed during the growth process of silicon carbide single crystals to increase the sublimation amount of silicon carbide polycrystalline powder, thereby achieving large-sized silicon carbide single crystal growth and meeting customer needs.

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] Currently, the physical vapor transport (PVT) method for growing silicon carbide single crystals involves placing polycrystalline silicon carbide raw material in a sealed chamber formed by a graphite crucible and a crucible lid in a vacuum or inert atmosphere. Silicon carbide seed crystals are then bonded to the inner wall of the crucible lid. The polycrystalline silicon carbide raw material at the bottom of the graphite crucible is heated and sublimated, thereby growing silicon carbide single crystals on the silicon carbide seed crystals. However, the current graphite crucible has a small charge capacity, and the height of the silicon carbide single crystals is relatively small, making it impossible to grow large silicon carbide single crystals on the silicon carbide seed crystals. This limits product size and fails 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, realize the growth of large-sized silicon carbide single crystals, 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 be used to add 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, and a crystal growth table is provided 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 holding silicon carbide polycrystalline powder and causing it to sublime when heated, thereby growing 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 holding silicon carbide polycrystalline powder. A discharge port is provided at the bottom of the material preparation bin, and a feed port is provided on the wing plate. The discharge port and the feed port are staggered. The crystal growth cover is used for driving the wing plate to move to a preset position to connect the feed port with the discharge port, thereby allowing the silicon carbide polycrystalline powder in the material preparation bin to flow to the crucible body.

[0008] Optionally, the material preparation bin is annular, a clearance hole is provided in the middle of the material preparation bin, the crystal growth cover is circular, the crystal growth cover and the material preparation bin are coaxially arranged, the crystal growth cover passes through the clearance hole, and partially extends into the crucible body, and the crystal growth cover rotates 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 clearance 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 in a circular array on the bottom wall 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 annular, 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 includes a material rake connected to the bottom of the crystal growth cover and arranged between the crystal growth cover and the crucible body, and the material rake extends radially along the crucible body.

[0014] Optionally, there are multiple material-dividing rakes, and the multiple material-dividing rakes are distributed in a ring array; and / or, the position of the material-dividing 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 utilizing the crystal growth cover 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.

[0017] The large-sized crucible for growing silicon carbide single crystals and the method for using the crucible provided by the present invention have the following beneficial effects:

[0018] The present invention provides a large-size 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. The crystal growth table is used to bond the silicon carbide seed wafer. The crucible body is used to hold silicon carbide polycrystalline powder and sublime it when heated, so as to grow silicon carbide single crystals on the silicon carbide seed wafer. The crystal growth cover is provided with a wing plate. The wing plate is movably arranged between a material preparation bin and the crucible body. The material preparation bin is used to hold silicon carbide polycrystalline powder. The bottom of the material preparation bin is provided with a discharge port. The wing plate is provided with a feed port. The discharge port and the feed port are staggered. The crystal growth cover is used to drive the wing plate to move to a preset position to connect the feed port with the discharge port, so that the silicon carbide polycrystalline powder in the material preparation bin flows to the crucible body. Compared with the existing technology, 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, so it is possible to add material during the growth process of silicon carbide single crystals to increase the sublimation amount of silicon carbide polycrystalline powder, thereby realizing the growth of large-sized silicon carbide single crystals and meeting customer needs.

[0019] 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 silicon carbide single crystal, the crucible body needs to be heated to sublime the silicon carbide polycrystalline powder in the crucible body, thereby realizing the function of growing 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, effectively improving the heat utilization rate, and the preheated silicon carbide polycrystalline powder can be quickly sublimated after being added to the crucible body, thereby increasing the growth rate of silicon carbide single crystal and improving production efficiency.

[0020] The method for using a large-sized crucible for growing silicon carbide single crystals provided by the present invention is applied to the crucible for growing large-sized silicon carbide single crystals. It can add material during the growth process of silicon carbide single crystals to increase the sublimation amount of silicon carbide polycrystalline powder, thereby realizing the growth of large-sized silicon carbide single crystals and meeting customer needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention 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 any creative work.

[0022] 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;

[0023] Figure 2A 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;

[0024] Figure 3 A cross-sectional view of a crucible body in a large-sized crucible for growing silicon carbide single crystals provided by an embodiment of the present invention;

[0025] 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.

[0026] 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-outer wall; 134-bottom wall; 135-cover plate; 136-annular cavity; 137-boss; 140-material rake. DETAILED DESCRIPTION

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only 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 herein can be arranged and designed in various different configurations.

[0028] 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 as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0029] 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, it does not need to be further defined or explained in subsequent drawings.

[0030] In the description of the present invention, it should be noted that the terms "inner," "outer," "upper," "lower," and "horizontal" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or the orientations or positional relationships in which the inventive product is typically placed when in use. These terms are intended solely to facilitate the description of the present invention and simplify the description, and are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third," etc., are used solely for distinction and should not be construed as indicating or implying relative importance.

[0031] In the description of the present invention, it should also be noted that, unless otherwise expressly specified or limited, the terms "disposed," "connected," "installed," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0032] The following describes some embodiments of the present invention in detail with reference to the accompanying drawings. In the absence of conflict, the features of the following embodiments can be combined with each other.

[0033] Please refer to Figures 1 to 4 The present invention provides a large-sized crucible 100 for growing silicon carbide single crystals. This crucible can be used to feed silicon carbide single crystals during growth, increasing the amount of sublimated silicon carbide polycrystalline powder, enabling the growth of large-sized silicon carbide single crystals to meet customer needs.

[0034] The crucible 100 for growing large-scale silicon carbide single crystals includes a crucible body 110, a crystal growth cover 120, and a material preparation bin 130. The crystal growth cover 120 is mounted on the crucible body 110. A crystal growth table 121 is provided on the inner top surface of the crystal growth cover 120, which is used to bond a silicon carbide seed wafer. The crystal growth cover 120 is connected to the crucible body 110 and is used to hold silicon carbide polycrystalline powder. When heated, the crucible body 110 sublimates the gaseous silicon carbide polycrystalline feedstock. The sublimated silicon carbide polycrystalline feedstock can smoothly enter the crystal growth cover 120, where it grows a silicon carbide single crystal on the silicon carbide seed wafer bonded to the crystal growth table 121, thereby achieving the silicon carbide single crystal growth function.

[0035] 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 hold silicon carbide polycrystalline powder. The bottom of the material preparation bin 130 is provided with a discharge port 131, and the wing plate 122 is provided with a feed port 123. The discharge port 131 and the feed port 123 are arranged in an offset manner. That is, under normal conditions, the discharge port 131 and the feed port 123 are not connected, 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, thereby allowing the silicon carbide polycrystalline powder in the preparation bin 130 to flow 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. Intermittent communication allows the silicon carbide polycrystalline powder in the preparation bin 130 to flow into the crucible body 110, realizing the feeding function. When the silicon carbide polycrystalline powder fed into the crucible body 110 reaches a second preset volume, the crystal growth cover 120 drives the wing plate 122 to reset, so that the feed port 123 and the discharge port 131 are offset. At this time, 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, feeding can be continuously performed during the silicon carbide single crystal growth process to increase the sublimation amount of silicon carbide polycrystalline powder, realize the growth of large-sized silicon carbide single crystals, and meet customer needs.

[0036] Furthermore, the material preparation bin 130 is annular, 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 rotates with the clearance hole 132. 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 pause function.

[0037] 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 to the material outlet 131, thereby realizing the material replenishment function.

[0038] It is worth noting that, compared to the prior art solutions that place a material bin outside the crucible and feed material through complex structures such as a spiral feed mechanism (which are complex and costly), the present invention optimizes the crucible structure by providing a material preparation bin 130 on the upper side of the crucible body 110. By driving the crystal growth cover 120 to rotate, this not only drives the silicon carbide seed crystal to rotate and facilitate crystal growth, but also enables the feeding of silicon carbide polycrystalline powder. This eliminates the need for material conveying related structures, simplifies the entire single crystal growth system, and reduces equipment costs. Furthermore, by controlling the misalignment or connection between the feed port 123 and the discharge port 131, the feed rate can be adjusted simply and reliably, eliminating the need for complex valves and other adjustment mechanisms, further simplifying the entire single crystal growth system and reducing equipment costs.

[0039] The preparation bin 130 includes an outer peripheral wall 133, a bottom wall 134, and a cover plate 135. The outer peripheral wall 133 surrounds and connects to the bottom wall 134. A clearance hole 132 is defined in the center of the bottom wall 134. Together, the outer peripheral wall 133, the bottom wall 134, and the crystal growth cap 120 form an annular cavity 136, which is used to hold silicon carbide polycrystalline powder for storage and preparation. The cover plate 135 is positioned outside the annular cavity 136 to seal it and prevent outside air from entering the crucible body 110 through the annular cavity 136, thereby ensuring the stability of silicon carbide single crystal growth. Specifically, the wing plate 122 is fitted under the bottom wall 134 , and the discharge port 131 is opened on the bottom wall 134 . The wing plate 122 can rotate relative to the bottom wall 134 driven by the crystal growth cover 120 so that the feed port 123 thereon can be selectively connected to the discharge port 131 .

[0040] Preferably, there are multiple discharge ports 131 and multiple feed ports 123, and multiple discharge ports 131 are arranged in a circular array on the bottom wall 134 with the give way hole 132 as the center. Each feed port 123 is selectively connected to a discharge port 131. Multiple discharge ports 131 and 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, realizing rapid feeding, and further improving the growth efficiency of silicon carbide single crystals.

[0041] In this embodiment, the number of discharge ports 131 and feed ports 123 is four, but it is not limited to this. In other embodiments, the number of discharge ports 131 and feed ports 123 can be two or six, and there is no specific limitation on the number of discharge ports 131 and feed ports 123.

[0042] It is worth noting that a limit ring 111 is provided on the top of the crucible body 110, and a wing plate 122 is annular. The wing plate 122 overlaps the limit ring 111 and rotates with the limit ring 111, that is, the wing plate 122 is rotatably provided between the bottom wall 134 and the limit ring 111. The wing plate 122 can rotate relative to the limit ring 111 under the drive of the crystal growth cover 120. 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 feed port 123 to prevent the silicon carbide polycrystalline powder flowing from the feed 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.

[0043] In this embodiment, a groove 112 is provided at the top of the crucible body 110, and a boss 137 is provided at 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, 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 crucible 100 for growing silicon carbide single crystals and improving the growth effect of silicon carbide single crystals.

[0044] Preferably, the crucible 100 for growing large-sized silicon carbide single crystals further includes a rake 140. The 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 rake 140 extends radially along the crucible body 110 and is used to level the silicon carbide polycrystalline powder added to the crucible body 110 to ensure uniform heating of the silicon carbide polycrystalline powder within the crucible body 110, thereby improving the growth of the silicon carbide single crystal.

[0045] Furthermore, there are multiple material-leveling rakes 140, which are arranged in a circular array. The multiple material-leveling rakes 140 work together to improve the raking effect. In this embodiment, there are four material-leveling rakes 140, but this is not limited to this. In other embodiments, the number of material-leveling rakes 140 can be two or six. The number of material-leveling rakes 140 is not specifically limited.

[0046] 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.

[0047] 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 is heated to a lower temperature. This causes the edge of the silicon carbide polycrystalline powder in the crucible body 110 to sublime faster, while the middle sublimates slower. Therefore, it is necessary to feed the edge of the crucible body 110. In the present invention, the positions corresponding to the discharge port 131 and the feed port 123, as well as the position of the material rake 140, are all located at the edge of the crucible body 110, so as to realize the functions of feeding and raking the edge of the crucible body 110, and the feeding 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 feeding balance effect.

[0048] Preferably, an upper shaft 124 is provided on 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 connection with a drive motor to drive the entire crystal growth cover 120 to rotate, thereby realizing the material feeding function, the material feeding pause function and the raking leveling function.

[0049] An 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:

[0050] 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.

[0051] 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.

[0052] 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 rotate in cooperation; 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 set 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 the material preparation bin 130 is filled with silicon carbide polycrystalline powder; 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.

[0053] 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.

[0054] 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 preparation bin 130 to flow into the crucible body 110 .

[0055] 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.

[0056] 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 the crucible body 110. The inner top surface of the crystal growth cover 120 is provided with a crystal growth platform 121 which is used to bond the silicon carbide seed wafer. The crucible body 110 is used to contain silicon carbide polycrystalline powder and sublimate it when heated, thereby growing a silicon carbide single crystal on the silicon carbide seed wafer. The crystal growth cover 120 is provided with a wing plate 122 which is movably arranged on the material preparation plate. 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, and a feed port 123 is provided on the wing plate 122. The discharge port 131 and the feed port 123 are staggered. The crystal growth cover 120 is used to drive the wing plate 122 to move to a preset position so that the feed port 123 is connected to the discharge port 131, thereby allowing the silicon carbide polycrystalline powder in the preparation bin 130 to flow into the crucible body 110. Compared with the prior art, the large-sized silicon carbide single crystal growth crucible 100 provided by the present invention adopts the feed port 123 provided on the wing plate 122 and the discharge port 131 provided at the bottom of the preparation bin 130. Therefore, it is possible to add material during the growth process of the silicon carbide single crystal to increase the sublimation amount of the silicon carbide polycrystalline powder, thereby achieving the growth of large-sized silicon carbide single crystals and meeting customer needs. The method for using the crucible for growing large-sized silicon carbide single crystals is simple in steps and has high production efficiency.

[0057] 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 sublime the silicon carbide polycrystalline powder in the crucible body 110, thereby realizing 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 130 to preheat the silicon carbide polycrystalline powder in the material preparation bin 130, 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.

[0058] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A large-sized crucible for growing silicon carbide single crystals, characterized in that: The crucible 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 to bond the silicon carbide seed wafer, the crucible body is used to hold silicon carbide polycrystalline powder and make it sublime when heated, so as to grow silicon carbide single crystals on the silicon carbide seed wafer, 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 to hold 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 to drive the wing plate to move to a preset position to connect the feeding port with the discharge port, so that the silicon carbide polycrystalline powder in the material preparation bin flows to the crucible body; The material preparation bin is annular, 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 is rotatably matched with the clearance hole; A limiting support ring is provided on the top of the crucible body. The wing plate is annular and overlaps the limiting support ring and rotates with the limiting support ring. The limiting support ring is staggered with the feeding port.

2. The large-sized crucible for growing silicon carbide single crystals according to claim 1, 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 makeshift 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.

3. The large-sized crucible for growing silicon carbide single crystals according to claim 2, characterized in that: There are multiple discharge ports and multiple feeding 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 feeding port is selectively connected to one discharge port.

4. The large-sized crucible for growing silicon carbide single crystals according to claim 1, characterized in that: 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 is matched with the groove.

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

6. The large-sized crucible for growing silicon carbide single crystals according to claim 5, characterized in that: There are multiple material rakes, and the multiple material rakes are distributed in a ring array; And / or, the position of the material rake corresponds to the position of the material passing port.

7. The large-sized crucible for growing silicon carbide single crystals according to claim 1, characterized in that: 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.

8. 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 according to any one of claims 1 to 7, the method for using the large-sized crucible for growing silicon carbide single crystals comprising: bonding a silicon carbide seed wafer to 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; heating the crucible body 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 feeding port is connected with the discharging port, thereby allowing the silicon carbide polycrystalline powder in the preparation bin to flow into the crucible body.

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