Feed tube, single crystal growth apparatus, and method of feeding

Abstract

The application discloses a feeding pipe, a single crystal growth device and a feeding method thereof. The feeding pipe is used in a single crystal growth device, and the single crystal growth device comprises a crucible and the feeding pipe. The crucible is suitable for containing silicon melt. The feeding pipe comprises a pipe body, the pipe body defines a feeding channel and a plurality of storage cavities for storing silicon raw materials. The plurality of storage cavities are communicated with the feeding channel. The feeding channel is suitable for feeding the silicon raw materials in the plurality of storage cavities into the crucible. A switch assembly is suitable for controlling the on-off of the plurality of storage cavities and the feeding channel respectively. According to the feeding pipe, the feeding amount of the silicon raw materials can be controlled more easily, and the spatter of high-temperature silicon melt caused by the silicon raw materials entering the silicon melt can be prevented, so that the safety and reliability of the operation of the single crystal growth device are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of silicon carbide single crystal growth, and in particular to a feeding tube, a single crystal growth device and a feeding method thereof. BACKGROUND

[0002] In the related art, multi-stage crystal pulling technology is usually used to reduce the cost of preparing crystal rods. After a crystal rod is pulled, a feeding tube is used to supplement the polycrystalline silicon raw material into the quartz crucible to make up for the reduced silicon melt due to the previous pulling of the crystal rod. However, when the feeding tube is used to supplement the polycrystalline silicon raw material into the quartz crucible, since there is a height difference between the feeding tube and the melt surface, when the feeding port of the feeding tube is opened, a large amount of polycrystalline silicon will fall from the feeding tube to the melt under the action of gravity, which is likely to cause splashing of the high-temperature silicon melt, affecting the reliability of the crystal growth device. SUMMARY

[0003] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application proposes a feeding tube which can prevent the splashing of high-temperature silicon melt during feeding and improve the safety and reliability of the single crystal growth device.

[0004] The present application also proposes a single crystal growth device having the above-mentioned feeding tube.

[0005] The present application also proposes a feeding method for a single crystal growth device, which can prevent the splashing of high-temperature silicon melt during feeding and improve the safety and reliability of the single crystal growth device.

[0006] According to the feeding tube of the first aspect of the present application, the single crystal growth device comprises a crucible and the feeding tube, the crucible is adapted to hold a silicon melt, and the feeding tube comprises a tube body defining a feeding channel and a plurality of storage cavities for storing silicon raw material, the plurality of storage cavities are in communication with the feeding channel, and the feeding channel is adapted to feed the silicon raw material in the plurality of storage cavities into the crucible; and a switch assembly adapted to control the opening and closing of the plurality of storage cavities and the feeding channel, respectively.

[0007] According to the feeding tube of the present application, by providing a plurality of storage cavities, one or more storage cavities can be selected to feed the silicon raw material when feeding into the crucible. Compared with the related art in which the feeding tube only has one storage cavity and all the silicon raw material is fed into the silicon melt when the storage cavity is opened, on the one hand, the amount of silicon raw material fed each time can be more easily controlled, and on the other hand, the splashing of high-temperature silicon melt caused by the large amount of silicon raw material entering the silicon melt can be prevented, thereby improving the safety and reliability of the single crystal growth device. In addition, the silicon raw material in the plurality of storage cavities is fed through the feeding channel, which is easier to control and adjust the feeding area.

[0008] According to some embodiments of the present application, the pipe body comprises: an outer pipe; an inner pipe located inside the outer pipe, the inner pipe defining the material conveying passage; a plurality of partitions spaced between the outer pipe and the inner pipe, the plurality of partitions and the outer pipe and the inner pipe jointly defining a plurality of material storage cavities, the inner pipe being formed with a plurality of communication openings corresponding to the plurality of material storage cavities, the communication openings communicating the material storage cavities and the material conveying passage, the switch assembly being adapted to open or close the plurality of communication openings.

[0009] Further, the plurality of partitions are spaced along the circumferential direction of the inner pipe, the plurality of partitions and the outer pipe and the inner pipe jointly defining a plurality of material storage cavities extending along the axial direction of the inner pipe and spaced along the circumferential direction of the inner pipe, the communication openings being located at positions adjacent to the bottom ends of the material storage cavities.

[0010] Still further, the bottom walls of the material storage cavities extend obliquely in a direction radially inward and axially downward of the inner pipe.

[0011] According to some embodiments of the present application, the switch assembly comprises: a plurality of switch doors corresponding to and adapted to the plurality of communication openings, the switch doors being pivotally connected to the inner pipe along the axial direction of the inner pipe and away from one end of the crucible.

[0012] According to some embodiments of the present application, the feeding pipe further comprises: a driving member connected to the pipe body, the driving member being adapted to drive the pipe body to rotate about the central axis of the pipe body to drive the plurality of material storage cavities to rotate.

[0013] In some embodiments, the feeding pipe further comprises: a guide cover adapted to block an end of the material conveying passage adjacent to the crucible, the guide cover being adapted to move between a first position and a second position, the material conveying passage being closed when the guide cover is in the first position, the material conveying passage being opened when the guide cover is in the second position, the silicon raw material in the material storage cavities being adapted to be conveyed to the crucible through the material conveying passage.

[0014] Further, the guide cover is adapted to move between the first position and the second position along the axial direction of the pipe body, at least a portion of the guide cover obliquely extending radially outward to form a guide surface in a direction away from the pipe body along the axial direction of the pipe body, the diameter of the guide cover being greater than the diameter of the material conveying passage, the guide surface blocking the material conveying passage when the guide cover is in the first position, the guide surface being spaced apart from the pipe body along the axial direction when the guide cover is in the second position, the silicon raw material in the material storage cavities being adapted to be conveyed to the crucible along the guide surface.

[0015] Further, the guide cover comprises: a first guide portion, a projection of the first guide portion in a reference plane is formed as a semicircle, the first guide portion is adapted to put silicon raw material into a first region of the crucible; a second guide portion, a projection of the second guide portion in the reference plane is formed as a semicircle, a radius of the projection of the second guide portion in the reference plane is smaller than a radius of the projection of the first guide portion in the reference plane, the second guide portion is radially opposite and connected to the first guide portion, the second guide portion is adapted to put silicon raw material into a second region of the crucible, a projection of the second region in the reference plane is located inside a projection of the first region in the reference plane, the reference plane is perpendicular to a central axis of the material feeding pipe, the guide cover is further adapted to rotate around an axis of the material feeding pipe to move the first guide portion or the second guide portion to a lower side of the material storage cavity which needs to put silicon material.

[0016] In some embodiments, the plurality of material storage cavities are adapted to store silicon raw materials of different sizes respectively, and the plurality of material storage cavities are sequentially arranged along a circumference of the pipe body according to sizes of the silicon raw materials stored.

[0017] Further, among the plurality of material storage cavities, a volume of the material storage cavity storing a larger size silicon raw material is greater than a volume of the material storage cavity storing a smaller size silicon raw material.

[0018] According to the single crystal growth equipment of the second aspect of the embodiments of the present application, the feeding pipe of the first aspect of the embodiments of the present application is provided.

[0019] According to the single crystal growth equipment of the embodiments of the present application, by providing the feeding pipe of the first aspect of the embodiments of the present application, the amount of silicon raw material put each time can be easily controlled, and in addition, splashing of high-temperature silicon melt caused by a large amount of silicon raw material entering the silicon melt can be prevented, and the safety and reliability of the operation of the single crystal growth equipment are improved.

[0020] According to the feeding method of the single crystal growth equipment of the third aspect of the embodiments of the present application, the single crystal growth equipment comprises: a crucible adapted to hold silicon melt, and a feeding pipe comprising: a pipe body defining a material feeding passage and a plurality of material storage cavities for storing silicon raw material, the plurality of material storage cavities are adapted to store silicon raw materials of different sizes respectively, and the plurality of material storage cavities are sequentially arranged along a circumference of the pipe body according to sizes of the silicon raw materials stored, the plurality of material storage cavities are all in communication with the material feeding passage, and the material feeding passage is adapted to transport silicon raw material in the plurality of material storage cavities into the crucible; a switch assembly adapted to control opening and closing of the plurality of material storage cavities and the material feeding passage respectively; and the feeding method comprises the following steps: controlling the feeding pipe to sequentially put silicon raw material in the plurality of material storage cavities in an order from small to large according to sizes of the silicon raw material stored in the plurality of material storage cavities.

[0021] According to the feeding method of the single crystal growth equipment, the plurality of storage cavities are arranged in the feeding pipe, and the silicon raw material in one or more storage cavities can be selected and fed into the crucible when feeding is needed. When the feeding pipe feeds the silicon raw material into the crucible, the plurality of storage cavities are sequentially opened in the order of the size of the silicon raw material stored in the plurality of storage cavities from small to large, so that the silicon raw material of small size fed first serves as a buffer layer for the silicon raw material of large size fed later, thereby avoiding the problem of splashing of the silicon melt, and also avoiding the problem of breaking of the crucible by the large-size polycrystalline silicon block, thereby ensuring the reliability of the equipment. Compared with the related art in which the feeding pipe is provided with only one storage cavity and all the silicon raw material is fed into the silicon melt when the storage cavity is opened, the feeding amount of the silicon raw material can be controlled each time, and the splashing of the high-temperature silicon melt caused by the large amount of silicon raw material entering the silicon melt can be prevented, thereby improving the safety and reliability of the operation of the single crystal growth equipment, and the silicon raw material in the plurality of storage cavities is fed through the feeding channel, so the falling area can be more easily controlled and adjusted.

[0022] In some embodiments of the present application, the feeding pipe further comprises a guide cover adapted to move along the axial direction of the pipe body between a first position and a second position, at least a part of the guide cover extends radially outwardly to form a guide surface in the axial direction of the pipe body, the diameter of the guide cover is larger than the diameter of the feeding channel, when the guide cover is in the first position, the guide surface blocks the feeding channel, when the guide cover is in the second position, the guide surface is spaced apart from the pipe body in the axial direction, the silicon material in the storage cavity is adapted to be fed into the crucible along the guide surface, the guide cover comprises a first guide part, the projection of the first guide part in a reference surface is semicircular, the first guide part is adapted to feed the silicon material into a first area in the crucible, a second guide part, the projection of the second guide part in the reference surface is semicircular, the radius of the projection of the second guide part in the reference surface is smaller than the radius of the projection of the first guide part in the reference surface, the second guide part is opposite to and connected with the first guide part in the radial direction, the second guide part is adapted to feed the silicon material into a second area in the crucible, the reference circle where the second area is located is smaller than the reference circle where the first area is located, the guide cover is further adapted to rotate around the axis of the feeding channel so that the first guide part or the second guide part is located at the lower side of the storage cavity where the silicon material needs to be fed, the feeding method further comprises the following steps: determining that the silicon material is fed into the first area, controlling the guide cover to rotate so that the first guide part is opposite to the communication port of the storage cavity, controlling the guide cover to move in the axial direction to open the feeding channel, controlling the switch assembly to open the communication port, and controlling the feeding pipe to rotate synchronously with the first guide part; or, determining that the silicon material is fed into the second area, controlling the guide cover to rotate so that the second guide part is opposite to the communication port of the storage cavity, controlling the guide cover to move in the axial direction to open the feeding channel, controlling the switch assembly to open the communication port, and controlling the feeding pipe to rotate synchronously with the second guide part; or, determining that the silicon material is fed into the first area and the second area, controlling the guide cover to move in the axial direction to open the feeding channel, controlling the switch assembly to open the communication port, and controlling the feeding pipe to rotate differentially with the guide cover.

[0023] Additional aspects and advantages of the present application will be made apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a schematic view of one embodiment of a feeding pipe according to an embodiment of the present application;

[0025] Figure 2 is a schematic view of another embodiment of a feeding pipe according to an embodiment of the present application;

[0026] Figure 3 is a schematic view of another embodiment of the filling tube according to an embodiment of the present application;

[0027] Figure 4 is a schematic view of another embodiment of the filling tube according to an embodiment of the present application;

[0028] Figure 5 is a schematic view of the reservoir opening of the filling tube shown in Figure 4

[0029] Figure 6 is a schematic view of another embodiment of the filling tube according to an embodiment of the present application;

[0030] Figure 7 is a schematic view of the reservoir opening of the filling tube shown in Figure 6

[0031] Figure 8 is a schematic view of another embodiment of the filling tube according to an embodiment of the present application;

[0032] Figure 9 is a schematic view of the reservoir opening of the filling tube shown in Figure 8

[0033] Figure 10 is a schematic view of the guiding cap of the filling tube shown in Figure 8

[0034] Reference signs:

[0035] filling tube 100,

[0036] tube body 1, outer tube 11, inner tube 12, partition 13, reservoir 14, feed channel 15,

[0037] switch assembly 2, switch door 21,

[0038] guiding cap 3, first guiding portion 31, second guiding portion 32, pulling mechanism 4, drive member 5,

[0039] silicon melt 200. DETAILED DESCRIPTION

[0040] Embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or like reference numerals represent the same or like elements or elements having the same or similar functions throughout. The embodiments described below by reference to the drawings are exemplary and are intended to explain the present application, and are not to be understood as limiting the present application.

[0041] Reference is made below to Figures 1-10 ​​​​A feeding tube 100 according to an embodiment of the first aspect of the present application is described.

[0042] As shown in Figure 1 A feeding tube 100 according to an embodiment of the first aspect of the present application can be used in a single crystal growth apparatus, for example, the single crystal growth apparatus can be a device for pulling a crystal rod, or can be another type of crystal growth furnace. The single crystal growth apparatus can include a crucible and the feeding tube 100.

[0043] The crucible is adapted to hold a silicon melt 200, and during crystal growth, the silicon raw material in the crucible becomes the silicon melt 200 in a molten state at high temperature. The feeding tube 100 can be used to add silicon raw material to the crucible when the silicon melt 200 in the crucible is reduced or insufficient, and to supplement the raw material required for crystal growth in time. The feeding tube 100 can include a tube body 1 and a switch assembly 2. The tube body 1 defines a feeding channel 15 and a plurality of storage cavities 14, and the plurality of storage cavities 14 can be used to store silicon raw material. The plurality of storage cavities 14 are in communication with the feeding channel 15, and the feeding channel 15 is adapted to deliver the silicon raw material in the plurality of storage cavities 14 to the crucible. That is, the silicon raw material stored in each storage cavity 14 can be delivered to the crucible through the feeding channel 15. The switch assembly 2 is adapted to control the opening and closing of the plurality of storage cavities 14 and the feeding channel 15, respectively, so as to deliver an appropriate amount of raw material according to the consumption of the silicon melt 200.

[0044] The feeding tube 100 according to the embodiment of the present application, by providing a plurality of storage cavities 14, one or more storage cavities 14 can be selected to deliver silicon raw material when feeding into the crucible is required. Compared with the related art feeding tube which only has one storage cavity and all the silicon raw material is delivered into the silicon melt when the storage cavity is opened, on the one hand, it is easier to control the amount of silicon raw material delivered each time, and on the other hand, it can prevent the splashing of high-temperature silicon melt 200 caused by a large amount of silicon raw material entering the silicon melt 200, thereby improving the safety and reliability of the operation of the single crystal growth apparatus. In addition, the silicon raw material in the plurality of storage cavities 14 is delivered through the feeding channel 15, which is easier to control and adjust the feeding area.

[0045] According to some embodiments of the present application, the pipe body 1 can include an outer pipe 11, an inner pipe 12, and a plurality of partitions 13. The inner pipe 12 is located inside the outer pipe 11, and the inner pipe 12 and the outer pipe 11 can be coaxially arranged, and the inner pipe 12 defines a material conveying passage 15. The plurality of partitions 13 are arranged between the outer pipe 11 and the inner pipe 12, and the plurality of partitions 13, the outer pipe 11, and the inner pipe 12 jointly define a plurality of material storage cavities 14. The inner pipe 12 is formed with a plurality of communication openings corresponding to the plurality of material storage cavities 14, the communication openings communicate the material storage cavities 14 and the material conveying passage 15, and the switch assembly 2 is adapted to open or close the plurality of communication openings. For example, each partition 13 can be arranged perpendicular to the central axis of the material conveying passage 15, and the plurality of partitions 13 are parallel to each other, and at this time, the plurality of material storage cavities 14 formed can be arranged along the axial direction of the material conveying passage 15; or each partition 13 can extend along the axial direction of the material conveying passage 15, and the plurality of partitions 13 are parallel to each other, and at this time, the plurality of material storage cavities 14 formed can be arranged along the circumferential direction of the material conveying passage 15. Thus, the overall structure of the feeding pipe 100 is simple, and it is convenient to manufacture and assemble.

[0046] Further, referring to Figures 1-3 , the plurality of partitions 13 can be arranged along the circumferential direction of the inner pipe 12, and the plurality of partitions 13, the outer pipe 11, and the inner pipe 12 jointly define a plurality of material storage cavities 14. Each material storage cavity 14 extends along the axial direction of the inner pipe 12, and the plurality of material storage cavities 14 are arranged along the circumferential direction of the inner pipe 12. The communication openings are located at the positions adjacent to the bottom ends of the material storage cavities 14, so that the communication openings can be closest to the crucible, and the height difference between the communication openings and the silicon melt 200 in the crucible is reduced, so as to avoid splashing of the silicon melt 200 caused by material falling.

[0047] Still further, referring to Figure 6 and Figure 7 , the bottom wall of the material storage cavity 14 extends in a direction of being inclined inwardly along the radial direction of the inner pipe 12 and downwardly along the axial direction. In this way, the silicon raw material in the material storage cavity 14 can be fully discharged, and accumulation of the silicon raw material at the bottom of the material storage cavity 14 and insufficient discharge caused thereby can be avoided.

[0048] According to some embodiments of the present application, referring to Figures 4-9 , the switch assembly 2 can include a plurality of switch doors 21. The plurality of switch doors 21 correspond to and are adapted to the plurality of communication openings, and the switch door 21 is pivotally connected to the inner pipe 12 at an end thereof along the axial direction of the inner pipe 12 and away from the crucible. For example, since the inner pipe 12 is annular, the cross section of the communication opening is also arc-shaped. Thus, the switch door 21 is formed as an arc-shaped plate adapted to the communication opening, so as to better close and open the communication opening. The top end of the switch door 21 and the inner pipe 12 are connected by a pivot shaft, so as to facilitate opening and closing of the switch door 21.

[0049] According to some embodiments of the present application, referring to Figures 1-9The feeding tube 100 may further include a driving element 5. Specifically, the driving element 5 is connected to the tube body 1 and is adapted to drive the tube body 1 to rotate around the central axis of the tube body 1 to drive the multiple storage chambers 14 to rotate. In this way, the feeding tube 100 can uniformly distribute material to each area in the crucible, ensuring that the silicon molten soup 200 is fed in the circumferential direction, preventing excessive material from falling into local areas, uneven heating, improving the melting efficiency of silicon raw materials, and thus ensuring the normal growth of crystals. Optionally, the driving element 5 can be installed on the isolation furnace of the single crystal growth equipment.

[0050] In some embodiments, reference Figures 4-9 The feed tube 100 may also include a guide cover 3. Specifically, the guide cover 3 is adapted to block one end of the feed channel 15 adjacent to the crucible (e.g., Figure 4 The guide cover 3 (located at the lower end of the conveying channel 15 shown in the diagram) can move between a first position and a second position. When the guide cover 3 is in the first position, it can block the lower end of the conveying channel 15, thus closing the conveying channel 15. When the guide cover 3 is in the second position, the conveying channel 15 is opened, allowing the silicon material in the storage chamber 14 to be conveyed to the crucible through the conveying channel 15. Furthermore, during the feeding process, under the guidance of the guide cover 3, the polycrystalline silicon material can be placed at a relatively outer position in the crucible, thereby reducing fluctuations in the molten silicon 200 at the center. Optionally, the feeding pipe 100 may also include a lifting mechanism 4, which is connected to the upper end of the guide cover 3. By using the up-and-down pulling of the lifting mechanism 4, the guide cover 3 can move between the first and second positions to open or close the conveying channel 15.

[0051] Furthermore, the guide cover 3 is adapted to move between a first position and a second position along the axial direction of the tube body 1. At least a portion of the upper surface of the guide cover 3 extends radially outward in a direction along the axial direction of the tube body 1 and away from the tube body 1 to form a guide surface. The diameter of the guide cover 3 is larger than the diameter of the material conveying channel 15. When the guide cover 3 is in the first position, the guide surface blocks the material conveying channel 15. When the guide cover 3 is in the second position, the guide surface is axially spaced from the tube body 1. The silicon raw material in the storage cavity 14 is adapted to be conveyed into the crucible along the guide surface.

[0052] For example Figure 4As shown, the guide cover 3 is formed in a conical shape with the cross-sectional area gradually decreasing from bottom to top, the upper surface of the guide cover 3 is formed as a guide surface, the projection of the guide cover 3 in the reference surface has a diameter greater than the projection of the material conveying passage 15 in the reference surface, when the silicon raw material is dropped, the silicon raw material falling from the material conveying passage 15 first falls on the guide cover 3 and then slides along the guide surface into the crucible, in this way, on the one hand, the guide cover 3 can play a buffering role for the silicon raw material, on the other hand, since the silicon raw material falls into the crucible from the edge of the guide cover 3, the dropping area of the silicon raw material in the crucible is determined by the size of the guide cover 3, so the dropping area of the silicon raw material can be adjusted by adjusting the size of the guide cover 3.

[0053] In some embodiments, with reference to Figures 8-10 , the guide cover 3 can include: a first guide portion 31 and a second guide portion 32. The projection of the first guide portion 31 in the reference surface is formed in a semicircular shape, the first guide portion 31 is adapted to drop the silicon raw material to the first area of the crucible. The projection of the second guide portion 32 in the reference surface is formed in a semicircular shape, the radius of the projection of the second guide portion 32 in the reference surface is smaller than the radius of the projection of the first guide portion 31 in the reference surface, the second guide portion 32 is radially opposite and connected to the first guide portion 31, the second guide portion 32 is adapted to drop the silicon raw material to the second area of the crucible, the projection of the second area in the reference surface is located inside the projection of the first area in the reference surface, and the reference surface is perpendicular to the central axis of the material conveying passage 15. The guide cover 3 is also adapted to rotate around the axis of the material conveying passage 15 to move the first guide portion 31 or the second guide portion 32 to the lower side of the storage cavity 14 where the silicon raw material needs to be dropped, in this way, by providing the guide cover 3 and setting the guide cover 3 to be adapted to rotate around the axis of the material conveying passage 15, the dropping area of the raw material in the crucible can be conveniently adjusted.

[0054] For example, when it is determined that the silicon raw material needs to be dropped in the first area, the guide cover 3 can be controlled to rotate to the position where the first guide portion 31 is opposite to the communication port of the storage cavity 14, then the guide cover 3 is controlled to move to the second position in the axial direction to open the material conveying passage 15, the switch door 21 is controlled to open the communication port, and the feeding pipe 100 is controlled to rotate synchronously with the first guide portion 31, at this time, the raw material in the storage cavity 14 can always fall along the guide surface of the first guide portion 31 to the first area of the crucible.

[0055] When it is determined that the silicon raw material needs to be dropped in the second area, the guide cover 3 can be controlled to rotate to the position where the second guide portion 32 is opposite to the communication port of the storage cavity 14, then the guide cover 3 is controlled to move to the second position in the axial direction to open the material conveying passage 15, the switch door 21 is controlled to open the communication port, and the feeding pipe 100 is controlled to rotate synchronously with the second guide portion 32, at this time, the raw material in the storage cavity 14 can always fall along the guide surface of the first guide portion 31 to the second area of the crucible.

[0056] When it is determined that the first region and the second region of the crucible both need to be fed with silicon raw materials, the guide cover 3 can be controlled to move axially to the second position to open the feeding channel 15, the switch assembly 2 can be controlled to open the communication port, and the feeding pipe 100 and the guide cover 3 can be controlled to rotate at different speeds. In this way, when the first guide part 31 rotates to be opposite to the communication port of the storage cavity 14, the silicon raw materials in the storage cavity 14 can fall to the first region of the crucible along the guide surface of the first guide part 31; when the second guide part 32 rotates to be opposite to the communication port of the storage cavity 14, the silicon raw materials in the storage cavity 14 can fall to the second region of the crucible along the guide surface of the second guide part 32.

[0057] In some embodiments, referring to Figures 1-3 , the plurality of storage cavities 14 are adapted to store silicon raw materials of different sizes respectively, and the plurality of storage cavities 14 are arranged in sequence along the circumference of the pipe body 1 according to the size of the silicon raw materials stored. For example, the plurality of storage cavities 14 include a first storage cavity 14, a second storage cavity 14, a third storage cavity 14, and a fourth storage cavity 14. The first storage cavity 14 is adapted to store silicon raw materials of a first size; the second storage cavity 14 is adapted to store silicon raw materials of a second size, which is larger than the first size; the third storage cavity 14 is adapted to store silicon raw materials of a third size, which is larger than the second size; and the fourth storage cavity 14 is adapted to store silicon raw materials of a fourth size, which is larger than the third size. The first storage cavity 14, the second storage cavity 14, the third storage cavity 14, and the fourth storage cavity 14 are arranged in sequence along the circumference of the pipe body 1. In this way, the feeding pipe 100 of the present application can feed silicon raw materials of multiple sizes according to actual needs.

[0058] When the feeding pipe 100 feeds silicon raw materials into the crucible, the plurality of storage cavities 14 can be opened in sequence according to the size of the silicon raw materials stored from small to large, so that the silicon raw materials of smaller sizes are first dropped into the silicon melt 200, and the silicon raw materials of larger sizes dropped later can use the silicon raw materials of smaller sizes as a buffer layer to prevent the silicon melt 200 from splashing. For example, the silicon raw materials of the first size are first added to the silicon melt 200, so that the silicon raw materials of the first size can form a first buffer layer on the surface of the silicon melt 200; then the silicon raw materials of the second size are added, so that the silicon raw materials of the second size fall onto the first buffer layer and can reduce the impact on the silicon melt 200 under the buffering action of the first buffer layer, and the silicon raw materials of the second size can form a second buffer layer; and so on, the silicon raw materials of the third size and the fourth size are sequentially added, so that the problem of splashing of the silicon melt 200 can be avoided under the buffering of the buffer layer, and the silicon raw materials of larger sizes can also be prevented from breaking the quartz crucible, thereby ensuring the reliability of the equipment.

[0059] Further, referring toFigures 2-3 In the plurality of storage cavities 14, the volume of the storage cavity 14 storing the larger size silicon raw material is larger than the volume of the storage cavity 14 storing the smaller size silicon raw material. For example, the sizes of the first storage cavity 14, the second storage cavity 14, the third storage cavity 14 and the fourth storage cavity 14 can be sequentially increased. For example, the central angle of the fourth storage cavity 14 can be 180°, and the central angles of the other three storage cavities 14 can be 40°, 60° and 80° respectively. Of course, the central angles of the plurality of storage cavities 14 can be reasonably selected according to actual needs, so that more large-size polysilicon materials can be contained. Of course, the angle range of each cavity can also be expanded, as long as the volume of the fourth storage cavity 14 is the largest.

[0060] Alternatively, in some other embodiments, the charging pipe 100 can also be configured such that the volumes of the first storage cavity 14 and the second storage cavity 14 are the same, the volumes of the third storage cavity 14 and the fourth storage cavity 14 are the same, and the volumes of the first storage cavity 14 and the second storage cavity 14 are smaller than the volumes of the third storage cavity 14 and the fourth storage cavity 14. Alternatively, the charging pipe 100 can also be configured such that the volumes of the second storage cavity 14 and the third storage cavity 14 are the same, the volume of the first storage cavity 14 is smaller than the volume of the second storage cavity 14, and the volume of the third storage cavity 14 is smaller than the volume of the fourth storage cavity 14. The volumes of the plurality of storage cavities 14 can be reasonably selected according to actual needs.

[0061] Next, a single crystal growth apparatus according to an embodiment of the second aspect of the present application is described.

[0062] The single crystal growth apparatus according to the second aspect of the present application includes the charging pipe 100 according to the above-described embodiments of the present application.

[0063] The single crystal growth apparatus according to the second aspect of the present application, by providing the charging pipe 100 according to the above-described embodiments, can more easily control the amount of silicon raw material to be added each time, and can prevent the splashing of the high-temperature silicon melt 200 caused by a large amount of silicon raw material entering the silicon melt 200, thereby improving the safety and reliability of the operation of the single crystal growth apparatus.

[0064] Next, a charging method of a specific embodiment of the single crystal growth apparatus according to the present application is described.

[0065] The charging method of the single crystal growth apparatus according to the embodiments of the present application, wherein the single crystal growth apparatus can be a device for pulling a crystal rod, or can be a crystal growth furnace of other types. The single crystal growth apparatus can include a crucible and the charging pipe 100.

[0066] The crucible is suitable for containing the silicon melt 200. During the crystal growth, the silicon raw material in the crucible becomes the silicon melt 200 in a molten state at high temperature. The feeding pipe 100 can be used to add the silicon raw material into the crucible when the silicon melt 200 in the crucible is reduced or insufficient, so as to supplement the raw material required for the crystal growth in time. The feeding pipe 100 can include a pipe body 1 and a switch assembly 2. The pipe body 1 defines a feeding channel 15 and a plurality of storage cavities 14. The plurality of storage cavities 14 can be used to store the silicon raw material. The plurality of storage cavities 14 are in communication with the feeding channel 15. The plurality of storage cavities 14 are suitable for storing the silicon raw material of different sizes respectively. The plurality of storage cavities 14 are arranged along the circumference of the pipe body 1 in sequence according to the size of the silicon raw material stored. The feeding channel 15 is suitable for feeding the silicon raw material in the plurality of storage cavities 14 into the crucible. That is, the silicon raw material stored in each storage cavity 14 can be fed into the crucible through the feeding channel 15. The switch assembly 2 is suitable for controlling the on-off of the plurality of storage cavities 14 and the feeding channel 15 respectively, so as to feed the appropriate amount of raw material according to the consumption of the silicon melt 200. The feeding method can include the following steps: controlling the feeding pipe 100 to feed the silicon raw material in the plurality of storage cavities 14 in sequence according to the size of the silicon raw material stored in the plurality of storage cavities 14 from small to large.

[0067] The plurality of storage cavities 14 include a first storage cavity 14, a second storage cavity 14, a third storage cavity 14 and a fourth storage cavity 14. The first storage cavity 14 is suitable for storing the silicon raw material of a first size. The second storage cavity 14 is suitable for storing the silicon raw material of a second size, which is larger than the first size. The third storage cavity 14 is suitable for storing the silicon raw material of a third size, which is larger than the second size. The fourth storage cavity 14 is suitable for storing the silicon raw material of a fourth size, which is larger than the third size. The first storage cavity 14, the second storage cavity 14, the third storage cavity 14 and the fourth storage cavity 14 are arranged along the circumference of the pipe body 1 in sequence. In this way, the feeding pipe 100 of the present application can feed the silicon raw material of multiple sizes according to the actual needs.

[0068] When the feeding pipe 100 is used to drop the silicon raw material into the crucible, the multiple storage cavities 14 can be opened in order of the size of the silicon raw material stored in the multiple storage cavities 14 from small to large, so that the silicon raw material with smaller size is dropped into the silicon melt 200 first, and the silicon raw material with larger size dropped later can use the silicon raw material dropped earlier as a buffer layer to prevent the silicon melt 200 from splashing. For example, the polycrystalline silicon blocks (silicon raw material) with the first size are added into the silicon melt 200 first, so that the polycrystalline silicon blocks with the first size can form a first buffer layer on the surface of the silicon melt 200; then the polycrystalline silicon blocks with the second size are dropped, so that the polycrystalline silicon blocks with the second size fall onto the first buffer layer, and the impact of the polycrystalline silicon blocks with the second size on the silicon melt 200 can be reduced under the buffering effect of the first buffer layer, and the polycrystalline silicon blocks with the second size can form a second buffer layer; and the polycrystalline silicon blocks with the third size and the fourth size are dropped in turn, so that the problem of splashing of the silicon melt 200 can be avoided under the buffering of the buffer layers, and the polycrystalline silicon blocks with larger size can also be prevented from breaking the quartz crucible, thereby ensuring the reliability of the equipment.

[0069] The feeding method of the single crystal growth equipment according to the embodiment of the application can avoid the problem of splashing of the silicon melt 200 during feeding, and can also prevent the polycrystalline silicon blocks with larger size from breaking the quartz crucible, thereby ensuring the reliability of the equipment.

[0070] The feeding method of the single crystal growth equipment according to the embodiment of the application can avoid the problem of splashing of the silicon melt 200 during feeding, and can also prevent the polycrystalline silicon blocks with larger size from breaking the quartz crucible, thereby ensuring the reliability of the equipment.

[0071] The feeding method of the single crystal growth equipment according to the embodiment of the application can avoid the problem of splashing of the silicon melt 200 during feeding, and can also prevent the polycrystalline silicon blocks with larger size from breaking the quartz crucible, thereby ensuring the reliability of the equipment.

[0072] The crucible is suitable for containing the silicon melt 200. During the crystal growth, the silicon raw material in the crucible becomes the silicon melt 200 in a molten state at high temperature. The feeding pipe 100 can be used to add the silicon raw material into the crucible when the silicon melt 200 in the crucible is reduced or insufficient, so as to supplement the raw material required for the crystal growth in time. The feeding pipe 100 can include a pipe body 1 and a switch assembly 2. The pipe body 1 defines a feeding channel 15 and a plurality of storage cavities 14 for storing the silicon raw material. The plurality of storage cavities 14 are in communication with the feeding channel 15, and are suitable for storing the silicon raw material of different sizes respectively. The plurality of storage cavities 14 are arranged along the circumference of the pipe body 1 in sequence according to the size of the silicon raw material stored therein, and the feeding channel 15 is suitable for feeding the silicon raw material in the plurality of storage cavities 14 into the crucible. That is, the silicon raw material stored in each storage cavity 14 can be fed into the crucible through the feeding channel 15. The switch assembly 2 is suitable for controlling the on-off of the plurality of storage cavities 14 and the feeding channel 15 respectively, so as to feed the appropriate amount of raw material according to the consumption of the silicon melt 200. The feeding method can include the following steps: controlling the feeding pipe 100 to feed the silicon raw material in the plurality of storage cavities 14 in sequence according to the size of the silicon raw material stored in the plurality of storage cavities 14 from small to large.

[0073] For example, the plurality of storage cavities 14 include a first storage cavity 14, a second storage cavity 14, a third storage cavity 14 and a fourth storage cavity 14. The first storage cavity 14 is suitable for storing the silicon raw material of a first size; the second storage cavity 14 is suitable for storing the silicon raw material of a second size, the second size being larger than the first size; the third storage cavity 14 is suitable for storing the silicon raw material of a third size, the third size being larger than the second size; and the fourth storage cavity 14 is suitable for storing the silicon raw material of a fourth size, the fourth size being larger than the third size. The first storage cavity 14, the second storage cavity 14, the third storage cavity 14 and the fourth storage cavity 14 are arranged along the circumference of the pipe body 1 in sequence. In this way, the feeding pipe 100 of the present application can feed the silicon raw material of multiple sizes according to the actual needs.

[0074] When the feeding tube 100 is used to drop the silicon raw material into the crucible, the multiple storage cavities 14 can be opened in order of the size of the silicon raw material stored in the multiple storage cavities 14 from small to large, so that the silicon raw material of small size is dropped into the silicon melt 200 first, and the silicon raw material of large size dropped later can use the silicon raw material dropped earlier as a buffer layer to prevent the silicon melt 200 from splashing. For example, the polycrystalline silicon blocks (silicon raw material) of the first size are added to the silicon melt 200 first, so that the polycrystalline silicon blocks of the first size can form a first buffer layer on the surface of the silicon melt 200; then the polycrystalline silicon blocks of the second size are dropped, so that the polycrystalline silicon blocks of the second size fall on the first buffer layer, and the impact of the polycrystalline silicon blocks of the second size on the silicon melt 200 can be reduced under the buffering effect of the first buffer layer, and the polycrystalline silicon blocks of the second size can form a second buffer layer; and the polycrystalline silicon blocks of the third size and the fourth size are dropped in turn, so that the problem of splashing of the silicon melt 200 can be avoided under the buffering of the buffer layers, and the polycrystalline silicon blocks of large size can also be prevented from breaking the quartz crucible, thereby ensuring the reliability of the equipment.

[0075] According to the feeding method of the single crystal growth equipment, the feeding tube 100 is provided with multiple storage cavities 14, so that one or more silicon raw materials in the storage cavities 14 can be selected to be dropped into the crucible when needed, and when the feeding tube 100 is used to drop the silicon raw material into the crucible, the multiple storage cavities 14 can be opened in order of the size of the silicon raw material stored in the multiple storage cavities 14 from small to large, so that the silicon raw material of small size dropped first can be used as a buffer layer for the silicon raw material of large size dropped later, thereby avoiding the problem of splashing of the silicon melt 200, and the polycrystalline silicon blocks of large size can also be prevented from breaking the crucible, thereby ensuring the reliability of the equipment. Compared with the related art in which the feeding tube is provided with only one storage cavity and all the silicon raw material is dropped into the silicon melt 200 when the storage cavity is opened, the feeding method can not only facilitate the control of the amount of silicon raw material dropped each time, but also prevent the splashing of the high-temperature silicon melt 200 caused by a large amount of silicon raw material entering the silicon melt 200, thereby improving the safety and reliability of the operation of the single crystal growth equipment, and the silicon raw material in the multiple storage cavities 14 can be dropped through the feeding channel 15, thereby being easier to control and adjust the dropping area.

[0076] In some embodiments, reference is made to Figures 8-10The feeding pipe 100 can further comprise a guide cover 3. Specifically, the guide cover 3 is adapted to block one end of the feeding passage 15 adjacent to the crucible, and the guide cover 3 can move between a first position and a second position. When the guide cover 3 is in the first position, the guide cover 3 can block the lower end of the feeding passage 15, and at this time the feeding passage 15 is closed. When the guide cover 3 is in the second position, the feeding passage 15 is opened, and at this time the silicon raw material in the storage cavity 14 can be transported to the crucible through the feeding passage 15. In addition, when feeding, the polycrystalline silicon material can be placed at a relatively outer position of the crucible under the guidance of the guide cover 3 body, so as to reduce the fluctuation of the silicon melt 200 at the center position. Optionally, the feeding pipe 100 can further comprise a lifting mechanism 4 connected to the upper end of the guide cover 3 body, and the lifting mechanism 4 is used to open or close the bottom end of the feeding passage 15 by pulling up and down.

[0077] Further, the guide cover 3 is adapted to move between the first position and the second position along the axial direction of the pipe body 1, and at least part of the guide cover 3 extends outwardly in the radial direction to form a guide surface in the axial direction of the pipe body 1 and away from the pipe body 1. The diameter of the guide cover 3 is greater than the diameter of the feeding passage 15. When the guide cover 3 is in the first position, the guide surface blocks the feeding passage 15. When the guide cover 3 is in the second position, the guide surface is spaced apart from the pipe body 1 in the axial direction, and the silicon raw material in the storage cavity 14 is adapted to be transported to the crucible along the guide surface.

[0078] The guide cover 3 is formed in a conical shape with a gradually decreasing cross-sectional area from bottom to top, and the upper surface of the guide cover 3 is formed as a guide surface. The projection of the guide cover 3 in the reference surface has a diameter greater than the projection of the feeding passage 15 in the reference surface. When the silicon raw material is placed, the silicon raw material falling from the feeding passage 15 first falls on the guide cover 3 and then slides along the guide surface into the crucible. In this way, on the one hand, the guide cover 3 can play a buffering role for the silicon raw material, and on the other hand, since the silicon raw material falls into the crucible from the edge of the guide cover 3, the falling area of the silicon raw material in the crucible is determined by the size of the guide cover 3, so the falling area of the silicon raw material can be adjusted by adjusting the size of the guide cover 3.

[0079] In some embodiments, the guide cover 3 can comprise a first guide portion 31 and a second guide portion 32. The first guide portion 31 has a projection in the reference plane in a semicircular shape, and is adapted to deliver the silicon material to the first region of the crucible. The second guide portion 32 has a projection in the reference plane in a semicircular shape, and the radius of the projection of the second guide portion 32 in the reference plane is smaller than that of the first guide portion 31 in the reference plane. The second guide portion 32 is radially opposite to and connected with the first guide portion 31, and is adapted to deliver the silicon material to the second region of the crucible. The projection of the second region in the reference plane is located inside the projection of the first region in the reference plane. The reference plane is perpendicular to the central axis of the material delivery channel. The guide cover 3 is further adapted to rotate around the axis of the material delivery channel 15 to move the first guide portion 31 or the second guide portion 32 to the lower side of the storage cavity 14 where the silicon material needs to be delivered. Thus, by providing the guide cover 3 and adapting the guide cover 3 to rotate around the axis of the material delivery channel 15, the delivery area of the material in the crucible can be conveniently adjusted.

[0080] The feeding method further comprises the following steps: when it is determined that the silicon material needs to be delivered to the first region, the guide cover 3 is controlled to rotate to the position where the first guide portion 31 is opposite to the communication opening of the storage cavity 14, then the guide cover 3 is controlled to move axially to the second position to open the material delivery channel 15, the switch door 21 is controlled to open the communication opening, and the feeding pipe 100 is controlled to rotate synchronously with the first guide portion 31. At this time, the material in the storage cavity 14 can always fall along the guide surface of the first guide portion 31 to the first region of the crucible.

[0081] When it is determined that the silicon material needs to be delivered to the second region, the guide cover 3 is controlled to rotate to the position where the second guide portion 32 is opposite to the communication opening of the storage cavity 14, then the guide cover 3 is controlled to move axially to the second position to open the material delivery channel 15, the switch door 21 is controlled to open the communication opening, and the feeding pipe 100 is controlled to rotate synchronously with the second guide portion 32. At this time, the material in the storage cavity 14 can always fall along the guide surface of the first guide portion 31 to the second region of the crucible.

[0082] When it is determined that the silicon material needs to be delivered to the first region and the second region of the crucible, the guide cover 3 is controlled to move axially to the second position to open the material delivery channel 15, the switch assembly 2 is controlled to open the communication opening, and the feeding pipe 100 is controlled to rotate at a differential speed with the guide cover 3. In this way, when the first guide portion 31 rotates to the position opposite to the communication opening of the storage cavity 14, the silicon material in the storage cavity 14 can fall along the guide surface of the first guide portion 31 to the first region of the crucible. When the second guide portion 32 rotates to the position opposite to the communication opening of the storage cavity 14, the silicon material in the storage cavity 14 can fall along the guide surface of the second guide portion 32 to the second region of the crucible. Thus, according to the feeding method of the present embodiment, the silicon material can be conveniently delivered to the first region and the second region of the crucible.

[0083] In the description of the application, it is necessary to understand that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the application and simplifying the description, and does not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the application.

[0084] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the application, the meaning of "multiple" is two or more, unless otherwise explicitly specified and limited.

[0085] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral; it can be mechanical connection, or electrical connection, or communication; it can be directly connected, or indirectly connected through intermediate medium, or the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0086] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples described in the present application and the features of different embodiments or examples without contradiction.

[0087] Although embodiments of the present application have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A feed tube for a single crystal growth apparatus, characterized by, The single crystal growth apparatus comprises a crucible adapted to hold a silicon melt and the feeding tube comprising: a tube body defining a feeding channel and a plurality of storage cavities for storing silicon raw material, the plurality of storage cavities are in communication with the feeding channel, the feeding channel is adapted to feed the silicon raw material in the plurality of storage cavities to the crucible, the tube body comprises an outer tube, an inner tube and a plurality of partitions, the inner tube is located inside the outer tube, the inner tube defines the feeding channel, the plurality of partitions are arranged between the outer tube and the inner tube, the plurality of partitions and the outer tube and the inner tube jointly define the plurality of storage cavities, a plurality of communication openings corresponding to the plurality of storage cavities are formed on the inner tube, the communication openings communicate the storage cavities and the feeding channel, the communication openings are located adjacent to the bottom end of the storage cavities; a switch assembly adapted to open or close the plurality of communication openings to control the on-off of the plurality of storage cavities and the feeding channel, the switch assembly comprises a plurality of switch doors corresponding to the plurality of communication openings, the switch doors are pivotally connected to the inner tube along the axial direction of the inner tube and away from the crucible; a guide cover adapted to block the end of the feeding channel adjacent to the crucible, the guide cover is adapted to move between a first position and a second position along the axial direction of the tube body, at least part of the guide cover extends radially outward to form a guide surface in the direction away from the tube body along the axial direction of the tube body, the diameter of the guide cover is greater than the diameter of the feeding channel, when the guide cover is in the first position, the guide surface blocks the feeding channel, the feeding channel is closed, when the guide cover is in the second position, the guide surface is spaced apart from the tube body along the axial direction, the feeding channel is opened, the silicon raw material in the storage cavities is adapted to be fed to the crucible through the feeding channel and along the guide surface.

2. The filling tube of claim 1, wherein, The plurality of partitions are arranged along the circumferential direction of the inner tube, the plurality of partitions and the outer tube and the inner tube jointly define the plurality of storage cavities extending along the axial direction of the inner tube and arranged along the circumferential direction of the inner tube.

3. The filling tube of claim 2, wherein, The bottom wall of the storage cavity extends in the direction radially inward and axially downward of the inner tube.

4. The fill tube of claim 1, wherein, Further comprising: a driving member connected to the tube body, the driving member is adapted to drive the tube body to rotate around the central axis of the tube body to drive the plurality of storage cavities to rotate.

5. The fill tube of claim 1, wherein, The guide cover comprises: a first guide portion, a projection of the first guide portion in a reference plane is formed in a semicircular shape, the first guide portion is adapted to feed the silicon raw material to a first area of the crucible; a second guide portion, a projection of the second guide portion in the reference plane being semicircular, a radius of the projection of the second guide portion in the reference plane being smaller than a radius of the projection of the first guide portion in the reference plane, the second guide portion being radially opposite and connected to the first guide portion, the second guide portion being adapted to deliver silicon material to a second region of the crucible, a projection of the second region in the reference plane being located inside a projection of the first region in the reference plane, the reference plane being perpendicular to a central axis of the delivery channel, the guide cover is further adapted to rotate around an axis of the delivery channel to move the first guide portion or the second guide portion to an underside of the storage cavity in need of delivery of silicon material.

6. The fill tube of claim 1, wherein a plurality of the storage cavities are adapted to store silicon material of different sizes respectively, the plurality of the storage cavities being arranged in sequence along a circumference of the tube body according to sizes of the silicon material stored.

7. A filling tube according to claim 6, wherein among the plurality of the storage cavities, a volume of the storage cavity storing silicon material of a larger size is greater than a volume of the storage cavity storing silicon material of a smaller size.

8. A single crystal growth apparatus, characterized by comprising: comprising: a charging tube according to any one of claims 1-7.

9. A feeding method for a single crystal growth apparatus, characterized in that, The single crystal growth device comprises a crucible and a feeding pipe, the crucible is suitable for containing silicon melt, the feeding pipe comprises a pipe body, the pipe body defines a feeding channel and a plurality of storage cavities for storing silicon raw materials, the plurality of storage cavities are suitable for storing silicon raw materials of different sizes respectively, the plurality of storage cavities are sequentially arranged along the circumference of the pipe body according to the size of the stored silicon raw materials, the plurality of storage cavities are in communication with the feeding channel, the feeding channel is suitable for conveying the silicon raw materials in the plurality of storage cavities into the crucible, the pipe body comprises an outer pipe, an inner pipe and a plurality of partitions, the inner pipe is located inside the outer pipe, the inner pipe defines the feeding channel, the plurality of partitions are arranged between the outer pipe and the inner pipe, the plurality of partitions and the outer pipe and the inner pipe jointly define the plurality of storage cavities, a plurality of communication openings corresponding to the plurality of storage cavities are formed on the inner pipe, the communication openings communicate the storage cavities and the feeding channel, and the communication openings are located at positions adjacent to the bottom ends of the storage cavities; a switch assembly is suitable for opening or closing the plurality of communication openings to respectively control the on-off of the plurality of storage cavities and the feeding channel, the switch assembly comprises a plurality of switch doors, the plurality of switch doors correspond to and are suitable for the plurality of communication openings, and the switch doors are pivotally connected to the inner pipe along the axial direction of the inner pipe and away from one end of the crucible; a guide cover is suitable for plugging an end of the feeding channel adjacent to the crucible, the guide cover is suitable for moving along the axial direction of the pipe body between a first position and a second position, at least part of the guide cover extends radially outward to form a guide surface in the direction away from the pipe body along the axial direction of the pipe body, the diameter of the guide cover is greater than the diameter of the feeding channel, when the guide cover is in the first position, the guide surface plugs the feeding channel, and the feeding channel is closed, when the guide cover is in the second position, the guide surface is spaced apart from the pipe body along the axial direction, the feeding channel is opened, and the silicon raw materials in the storage cavities are suitable for being conveyed to the crucible through the feeding channel and along the guide surface, The feeding method comprises the following steps: controlling the feeding pipe to sequentially feed the silicon raw materials in the plurality of storage cavities in the order from small to large according to the size of the silicon raw materials stored in the plurality of storage cavities.

10. The charging method of a single crystal growth apparatus according to claim 9, wherein The guide cover comprises: a first guide part, a projection of which in a reference plane is semicircular, the first guide part being adapted to put silicon raw material into a first area in the crucible; a second guide part, a projection of which in the reference plane is semicircular, a radius of the projection of the second guide part in the reference plane being smaller than a radius of the projection of the first guide part in the reference plane, the second guide part being radially opposite and connected to the first guide part, the second guide part being adapted to put silicon raw material into a second area in the crucible, the second area being located in a reference circle smaller than a reference circle in which the first area is located, the guide cover being further adapted to rotate around an axis of the material conveying passage so that the first guide part or the second guide part is located below the material storage cavity in which silicon material needs to be put, The feeding method further comprises the following steps: determining that the silicon raw material is put in the first area, controlling the guide cover to rotate so that the first guide part is opposite to the communication port of the material storage cavity, controlling the guide cover to move axially to open the material conveying passage, controlling the switch assembly to open the communication port, and controlling the feeding pipe to rotate synchronously with the first guide part; or determining that the silicon raw material is put in the second area, controlling the guide cover to rotate so that the second guide part is opposite to the communication port of the material storage cavity, controlling the guide cover to move axially to open the material conveying passage, controlling the switch assembly to open the communication port, and controlling the feeding pipe to rotate synchronously with the second guide part; or determining that the silicon raw material is put in the first area and the second area, controlling the guide cover to move axially to open the material conveying passage, controlling the switch assembly to open the communication port, and controlling the feeding pipe to rotate at a differential speed with the guide cover.

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