Feeding device and single crystal furnace

Abstract

The utility model provides a feeding device and a single crystal furnace, and the feeding device comprises a feeding cylinder which is provided with a material accommodating space; the feeding pipe comprises a first end part and a second end part which are opposite to each other, the first end part is positioned in the feeding cylinder, and the second end part is positioned outside the feeding cylinder; and the feeding pipe is used for guiding substances to be fed into or out of the accommodating space. The loss of the dopant can be avoided, the expected doping amount of the dopant is ensured, and the yield of the monocrystalline silicon wafer is effectively improved.

Description

Technical Field

[0001] The utility model relates to the technical field of solar photovoltaics, in particular to a feeding device and a single crystal furnace. Background Art

[0002] In the current Czochralski process for producing single crystal silicon, dopants need to be added to change the resistivity of the single crystal silicon. Usually, before crystal growth, in order to prevent the volatilization of the dopant, the conventional method is to place the dopant in the last bucket of polysilicon material, and the dopant is added to the molten silicon during the feeding process. However, when the dopant is added in the above method, due to the high temperature of the molten silicon and the strong volatility of most dopants at high temperatures, the dopant will volatilize in advance, so that the resistivity of the produced single crystal silicon rod cannot reach the target value, which seriously affects the yield of single crystal silicon wafers. Utility Model Content

[0003] In view of the above problems, embodiments of the present invention are proposed to provide a charging device and a single crystal furnace that overcome the above problems or at least partially solve the above problems.

[0004] In order to solve the above problems, in a first aspect, the embodiments of the present invention disclose a feeding device and a single crystal furnace, comprising:

[0005] A feeding cylinder having a material storage space;

[0006] A feeding tube, comprising a first end and a second end opposite to each other, wherein the first end is located inside the feeding cylinder and the second end is located outside the feeding cylinder; the feeding tube guides the material to be added into or out of the material holding space.

[0007] By adopting the technical solution of the present application, the substance to be added is added into the feeding barrel through the feeding tube. When adding the substance to be added into the molten silicon for crystal growth, the loss caused by premature volatilization of the added substance is avoided, thereby improving the yield of silicon wafers processed from silicon rods.

[0008] Optionally, the feeding cylinder includes a cylinder body and a first enclosing portion and a second enclosing portion arranged oppositely at two ends of the cylinder body;

[0009] The cylinder, the first enclosing portion and the second enclosing portion enclose a material holding space;

[0010] The feeding pipe is passed through the first enclosure, and the first end portion is spaced apart from the second enclosure at a side away from the second end portion, and the first end portion is spaced apart from the cylinder.

[0011] By adopting the technical solution of the present application, the cylinder, the first enclosure and the second enclosure form a sealed material containing channel, and the first end of the feeding tube does not contact the cylinder and the second enclosure, thereby preventing the dopant from being retained in the feeding tube; when the crystal grows, when the dopant is added from the feeding cylinder to the molten silicon through the feeding tube, the sealed material containing channel can avoid premature volatilization and ensure that the dopant is completely added to the molten silicon, thereby improving the final yield of the silicon wafer.

[0012] Optionally, the length of the feeding tube extending out of the feeding cylinder is H1, 80mm≤H1≤150mm.

[0013] By adopting the technical solution of the present application, the length of the feeding tube extending out of the feeding barrel is greater than or equal to 80 mm, and the feeding tube has sufficient length to extend into the molten silicon. In this way, when the dopant is passed in and out of the feeding tube, the vaporized dopant can be prevented from forming bubbles on the surface of the molten silicon and being lost; the length of the feeding tube extending out of the feeding barrel is less than or equal to 150 mm, which can prevent the feeding tube from being extended too long, thereby allowing it to be closer to the molten silicon and prevent the feeding tube from being damaged at high temperature.

[0014] Optionally, the height of the feeding pipe in the direction from the first end to the second end is H2, and 130 mm ≤ H2 ≤ 360 mm.

[0015] By adopting the technical solution of the present application, the height of the feeding tube along the direction from the first end to the second end is less than or equal to 360 mm, which can avoid the dopant adhering to the inner wall of the feeding tube due to the low temperature of the first end due to the distance from the high-temperature environment during feeding; the height of the feeding tube along the direction from the first end to the second end is greater than or equal to 130 mm, ensuring that sufficient dopant can be added into the feeding barrel at one time, thereby improving the feeding efficiency.

[0016] Optionally, the length of the feeding tube inside the feeding barrel is H4, 50mm≤H4≤210mm.

[0017] By adopting the technical solution of the present application, the length of the feeding tube inside the feeding barrel is greater than or equal to 50 mm, preventing the added material from flowing out of the feeding tube; the length of the feeding tube inside the feeding barrel is less than or equal to 210 mm. The feeding tube is too long, which affects the capacity of the material storage space; at the same time, it prevents the material from being added to the feeding barrel from the feeding tube.

[0018] Optionally, the wall thickness t1 of the cylinder is greater than or equal to the wall thickness t2 of the feeding pipe, 2mm≤t1

[0019] ≤10mm.

[0020] By adopting the technical solution of the present application, the wall thickness of the cylinder is greater than or equal to 2 mm, and the structure of the cylinder has a certain strength, which avoids the risk of the feeding cylinder breaking; the wall thickness of the cylinder of the feeding cylinder is less than or equal to 10 mm, so that the heat conduction of the feeding cylinder is more uniform during heat conduction, and the generation of thermal stress and cracks is avoided during the doping process.

[0021] Optionally, a height of the feeding cylinder in a direction from the first enclosing portion to the second enclosing portion is H3, and 100mm≤H3≤300mm.

[0022] By adopting the technical solution of the present application, the height of the feeding barrel along the direction from the first enclosure to the second enclosure is less than or equal to 300 mm, which can avoid the low temperature of the feeding barrel at one end of the first enclosure, prevent the dopant from condensing on the inner wall of the feeding barrel, and thus reduce the amount of dopant attached to the inner wall of the feeding barrel; the height of the feeding barrel along the direction from the first enclosure to the second enclosure is greater than or equal to 100 mm, which can avoid the height inside the feeding barrel being too small, the dopant being unable to enter the feeding barrel, and resulting in insufficient usage of the dopant, thereby ensuring that the feeding barrel can accommodate a sufficient amount of dopant.

[0023] Optionally, the outer diameter of the cylinder is D1, 100mm≤D1≤200mm; the outer diameter of the feeding pipe is D2, 10mm<D2<100mm.

[0024] By adopting the technical solution of the present application, by controlling the outer diameter of the barrel of the feeding barrel to be greater than or equal to 100 mm, it can be ensured that a sufficient amount of dopant can be added in one go; the outer diameter of the feeding barrel is controlled to be less than or equal to 200 mm to avoid the problems of thermal stress and cracks caused by uneven heat conduction of the feeding barrel during the doping process; at the same time, the outer diameter of the feeding tube is greater than 10 mm to avoid being too small so that the dopant cannot be added to the feeding barrel; the outer diameter of the feeding tube is less than 100 mm to avoid the flow rate of the vaporized dopant being added to the molten silicon being too low when adding the material.

[0025] Optionally, the cross-sectional shape of the feeding tube along the direction from the first end to the second end is linear or curved.

[0026] By adopting the technical solution of the present application, when the cross-section of the feeding tube is linear, the feeding rate is faster, thereby improving the feeding efficiency; when the cross-section of the feeding tube is curved, the risk of dopant clogging in the feeding tube can be prevented.

[0027] In a second aspect, an embodiment of the present utility model further discloses a single crystal furnace, comprising a weight hammer and the above-mentioned feeding device, wherein the feeding device further comprises a connecting piece;

[0028] The connecting piece is connected to a side of the feeding barrel facing away from the feeding pipe. When feeding, the connecting piece is connected to the heavy hammer.

[0029] By adopting the technical solution of the present application, doping can be achieved without the need for additional connecting components.

[0030] The present invention has the following advantages:

[0031] In an embodiment of the present invention, the feeding barrel has a material accommodating space, and the feeding tube includes a first end and a second end relative to each other, the first end is located inside the feeding barrel, and the second end is located outside the feeding barrel, so that the dopant can be added to the feeding barrel through the feeding tube; when adding material, the second end of the feeding tube is placed in the molten silicon on a side away from the first end, so that the vaporized dopant is added to the molten silicon along the enclosed space. The feeding device of the present application has a simple structure, is easy to operate, and has strong practicality; the use of the feeding device of the present application can avoid losses caused by volatilization of dopants, and effectively improve the yield of single crystal silicon wafers. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a structural diagram of a feeding device of the utility model;

[0033] Figure 2 This is a cross-sectional view of a feeding device of the utility model

[0034] Figure 3 This is a structural diagram of the cooperation between a connecting piece and a heavy hammer of the utility model;

[0035] Figure 4 This is a schematic structural diagram of a feeding device for adding dopants according to the present invention;

[0036] Figure 5 This is a schematic diagram of a second end portion of the present invention being inserted into molten silicon at a side away from the first end portion;

[0037] Figure 6 It is a size schematic diagram of a feeding device of the present utility model.

[0038] Description of reference numerals:

[0039] 100. Feeding device; 1. Feeding cylinder; 11. Cylinder body; 12. First enclosure; 13. Second enclosure; 2. Feeding pipe; 21. First end; 22. Second end; 3. Connector; 31. Mounting hole; 4. Dopant; 200. Weight; 300. Furnace body; 400. Guide cylinder; 500. Heater; 600. Insulation cylinder; 701. Crucible; 702. Crucible side; 703. Drag rod; 800. Molten silicon. DETAILED DESCRIPTION

[0040] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0041] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly refer to one or more of these features. In the description of this utility model, unless otherwise specified, "plurality" means two or more. Furthermore, "and / or" in the specification and claims refers to at least one of the connected items, and the character " / " generally indicates an "or" relationship between the connected items.

[0042] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation to the present invention.

[0043] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0044] It should be noted that the feeding device 100 described in the embodiment of the present invention can be used for feeding operations, can be used in the Czochralski method silicon crystal growth process, and can also be used in other processes. The feeding device 100 can be used to add substances to be added, such as: dopants 4, chemicals or other substances to be added. The substances to be added can be solid or liquid at a preset temperature and below the preset temperature, and can be gaseous at a temperature above the preset temperature. In the embodiment of the present invention, only the application of the feeding device 100 in the single crystal growth process and the substance to be added being the dopant 4 are used as an example for explanation. Other situations can refer to the settings. Specifically, the dopant 4 can be vaporized at a temperature above the preset temperature. Specifically, the dopant 4 can be phosphorus, antimony, etc., which can change the resistivity of the single crystal silicon.

[0045] One of the core concepts of the embodiment of the present invention is to disclose a feeding device 100, such as Figure 1 and Figure 2 As shown, the feeding device 100 includes: a feeding barrel 1, which has a material holding space; a feeding pipe 2, which includes a first end 21 and a second end 22 relative to each other, the first end 21 is located inside the feeding barrel 1, and the second end 22 is located outside the feeding barrel 1; the feeding pipe guides the material to be added into or out of the material holding space.

[0046] In the embodiment of the present invention, the feeding barrel 1 has a material storage space, and the feeding tube 2 includes a first end 21 and a second end 22 opposite to each other. The first end 21 is located inside the feeding barrel 1, and the second end 22 is located outside the feeding barrel 1. In this way, the dopant 4 can be added to the feeding barrel 1 through the feeding tube 2. During the addition, the dopant 4 is added from the feeding barrel 1 to the molten silicon 800, avoiding the risk of premature volatilization of the dopant 4 when adding the dopant 4 separately. The feeding device of the present application has a simple structure, is easy to operate, and has strong practicality.

[0047] Optionally, when adding material, the second end 22 of the feeding tube 2 away from the end of the first end 21 can be placed in the molten silicon 800. The high temperature of the molten silicon 800 causes the dopant 4 in the feeding barrel 1 to vaporize and directly enter the molten silicon 800 along the feeding tube 2, avoiding the loss of the dopant 4 and ensuring that the dopant 4 is added to the single crystal silicon rod, thereby improving the yield of silicon wafers processed from the silicon rod.

[0048] Specifically, the first end 21 is spaced apart from the inner wall of the feeding barrel 1. When the feeding device 100 is used, the end of the feeding barrel 1 where the feeding tube 2 is not provided can be directed upward, and the end where the feeding tube 2 is provided can be directed downward. The end of the second end 22 away from the first end 21 can then be placed in the molten silicon 800, so that the vaporized dopant 4 can be added to the molten silicon 800. Since the vaporized dopant 4 directly enters the molten silicon 800 along the confined space, the loss of the dopant 4 can be avoided, effectively ensuring that the doping amount of the dopant 4 is achieved. The resistivity of the produced single crystal silicon rod can reach the target value, thereby improving the yield of the single crystal silicon rod and the overall resistivity distribution.

[0049] It should be noted that the first end 21 is spaced apart from the inner wall of the feeding barrel 1, which means that there is no contact between the first end 21 and the upper and side parts of the feeding barrel 1, thereby ensuring the material storage space in the feeding barrel 1; at the same time, it prevents the dopant 4 from being blocked, affecting the dopant 4 from entering or leaving the material storage space.

[0050] In the embodiment of the present invention, the feeding device 100 is made of high-purity and refractory materials such as quartz, silicon carbide, carbon-carbon materials, etc., and the material of the entire feeding device 100 can be the same.

[0051] The feeding device 100 includes a feeding cylinder 1, which has a material storage space and is used to

[0052] The dopant 4 is accommodated. The feeding barrel 1 can be a rotating body structure, a cubic structure, or other irregular shaped structures. The feeding barrel 1 can be an integrally formed structure, or a spliced ​​structure.

[0053] Specifically, the feeding device 100 further includes a feeding pipe 2 for conveying the dopant 4. The feeding pipe 2 may include a first end 21 and a second end 22 opposite to each other. The first end 21 may be located inside the feeding barrel 1, and the second end 22 may be located outside the feeding pipe 2. The feeding pipe 2 may connect the inside and outside of the feeding barrel 1, facilitating the addition of material into the feeding barrel 1 through the feeding pipe 2, or discharging vaporized material through the feeding barrel 1.

[0054] Optionally, the cross-sectional shape of the feeding tube 2 along the direction from the first end 21 to the second end 22 is linear or curved, which can improve the structural diversity of the feeding tube 2.

[0055] Specifically, when the cross section of the feeding tube 2 is linear, the feeding rate is faster, thereby improving the feeding efficiency; and when the cross section of the feeding tube 2 is curved, the risk of the dopant 4 being blocked in the feeding tube 2 can be prevented.

[0056] like Figure 3 As shown, it illustrates a situation where the cross-sectional shape of the feeding tube 2 along the direction from the first end 21 to the second end 22 is a straight line.

[0057] Optionally, the feeding barrel 1 may include a barrel 11 and a first enclosing portion 12 and a second enclosing portion 13 relatively arranged at both ends of the barrel 11; the first enclosing portion 12 and the second enclosing portion 13 are respectively used to seal the two ends of the barrel 11; so that the barrel 11, the first enclosing portion 12 and the second enclosing portion 13 are jointly enclosed to form a material storage space to accommodate the dopant 4.

[0058] Specifically, the cylinder 11, the first enclosing portion 12 and the second enclosing portion 13 can be integrally formed, or can be spliced ​​together by bonding or welding. The specific selection can be made according to actual needs, and the embodiment of the present utility model does not make any specific limitations on this.

[0059] Specifically, the feeding tube 2 can be passed through the first enclosure 12 so that the first end 21 of the feeding tube 2 extends into the feeding barrel 1 and the second end 22 of the feeding tube 2 extends out of the feeding barrel 1 .

[0060] Furthermore, the first enclosure 12 may be provided with a through hole communicating with the material storage space; the feeding tube 2 may be passed through the through hole and fixedly connected to the first enclosure 12 via the wall of the through hole, thereby integrating and fixing the feeding barrel 1 and the feeding tube 2. The shape of the through hole may be adapted to the shape of the feeding tube 2 to improve the reliability of the assembly between the feeding barrel 1 and the feeding tube 2.

[0061] Optionally, the feeding tube 2 and the feeding barrel 1 can be fixedly connected by bonding or welding. Among them, the feeding tube 2 and the feeding barrel 1 are fixedly connected by welding, which can improve the reliability of the connection operation between the feeding tube 2 and the feeding barrel 1, as well as the reliability of the connection between the feeding tube 2 and the feeding barrel 1.

[0062] Specifically, the cylinder 11 can have a first inner wall and a first outer wall; the first inner wall can be enclosed to form a rotational body shape, or a cube shape, or other irregular shapes, etc.; the first outer wall can be enclosed to form a rotational body shape, or a cube shape, or other irregular shapes, etc.

[0063] Specifically, the feeding tube 2 may have a second inner wall and a second outer wall. The second outer wall may be assembled with the hole wall of the through hole, and the second inner wall may be enclosed to form a channel for transmitting the dopant 4 .

[0064] Specifically, the feeding tube 2 can be a solid of revolution structure, a cubic structure, or other irregular shapes. The second inner wall can be enclosed to form a solid of revolution shape, a cubic shape, or other irregular shapes; the second outer wall can be enclosed to form a solid of revolution shape, a cubic shape, or other irregular shapes.

[0065] Specifically, taking the example of both the feeding tube 2 and the feeding barrel 1 being a rotating body, the direction from the first end 21 to the second end 22 can be parallel to the axis of the feeding tube 2 and the axis of the feeding barrel 1. To improve the structural stability of the feeding device 100, the axis of the feeding tube 2 and the axis of the feeding barrel 1 can coincide.

[0066] The feeding device 100 may include a preparation process and a feeding process. The preparation process is used to realize the addition of the dopant 4 to the feeding device 100. During the preparation process, the end of the feeding barrel 1 where the feeding tube 2 is not set can be facing downward, and the end of the feeding tube 2 can be set upward, so that the second end 22 of the feeding tube 2 is placed upward, and the dopant 4 can be added to the feeding tube 2 from the second end 22, and the dopant 4 can be spread flat on the second enclosure 13; then the feeding barrel 1 can be tilted and rotated, so that the end of the feeding barrel 1 where the feeding tube 2 is not set is facing upward, and the end of the feeding tube 2 can be set downward, so that the second end 22 of the feeding tube 2 is placed downward, and the dopant 4 can flow along the barrel body 11 to the first enclosure 12, and the dopant 4 can be spread flat on the first enclosure 12.

[0067] For example, the process of switching the feeding barrel 1 from one end with the feeding tube 2 facing upward to the one end without the feeding tube 2 facing upward may include: first turning the feeding barrel 1 45 degrees, then slowly turning the feeding barrel 1 45 degrees, and then turning the feeding barrel 1 90 degrees; or continuously and slowly turning the feeding barrel 1

[0068] Tube 1 is turned over 180°.

[0069] Specifically, the feeding process is used to add the dopant 4 in the feeding device 100 to the molten silicon 800. During the feeding process, the feeding device 100 can be adjusted to the top of the molten silicon 800, such as Figure 4 and Figure 5 As shown, the second end 22 of the feeding tube 2, which is away from the first end 21, is inserted into the molten silicon 800. Under high temperature conditions, the dopant 4 vaporizes, causing the gas pressure in the feeding barrel 1 to change. The vaporized dopant 4 can enter the feeding tube 2 from the first end 21 of the feeding tube 2, and then be added to the molten silicon 800 from the second end 22 of the feeding tube 2, thereby adding the dopant 4 to the molten silicon 800. Since the first end 21 of the feeding tube 2 is located in the feeding barrel 1 and the second end 22 of the feeding tube 2 is located in the molten silicon 800, during this feeding process, the vaporized dopant 4 can directly enter the molten silicon 800 from the feeding device 100, allowing the vaporized dopant 4 to directly enter the molten silicon 800 along the enclosed space, avoiding the loss of the dopant 4, effectively ensuring that the dopant 4 reaches the desired doping amount, and the resistivity of the produced single crystal silicon rods can reach the target value, thereby improving the yield rate and overall resistivity distribution of the single crystal silicon rods.

[0070] Specifically, along the direction from the first end 21 to the second end 22, there is a gap between the end of the first end 21 away from the second end 22 and the second enclosed portion 13. On the one hand, this allows the dopant 4 to enter the feeding barrel from the gap; on the other hand, it prevents the dopant 4 from flowing out of the feeding tube 2 during the process of the feeding barrel 1 rotating from the end where the feeding tube 2 is set to the end where the feeding tube 2 is not set to the top.

[0071] Furthermore, there is a gap between the first end 21 and the barrel 11. On the one hand, when the feeding barrel 1 rotates from the end with the feeding tube 2 facing upward to the end without the feeding tube 2 facing upward, the dopant 4 can flow from the gap to the first enclosure 12; on the other hand, the range of the material storage space can be effectively guaranteed, so that the material storage space can accommodate a sufficient amount of dopant 4 and ensure that the dopant 4 can flow in the material storage space.

[0072] Specifically, taking the feeding pipe 2 and the feeding cylinder 1 as a rotating body as an example, the minimum interval between the first inner wall and the second outer wall is the diameter difference between the first inner wall and the second outer wall.

[0073] Alternatively, as Figure 6 As shown, the outer diameter of the cylinder 11 is D1, 100mm≤D1≤200mm.

[0074] In the embodiment of the present invention, by controlling the outer diameter of the barrel 11 of the feeding barrel 1 to be greater than or equal to 100 mm, the volume of the feeding barrel 1 can be guaranteed to ensure that a sufficient amount of dopant 4 can be added at one time.

[0075] By controlling the barrel 11 of the feeding barrel 1 to be less than or equal to 200 mm, problems of thermal stress and cracks caused by uneven heat conduction of the feeding barrel 1 during the doping process can be avoided.

[0076] Specifically, the outer diameter of the cylinder 11 can be 100 mm, 110 mm, 166 mm, 195 mm, 200 mm, etc.

[0077] Optionally, the outer diameter of the feeding tube 2 is D2, 10 mm < D2 < 100 mm.

[0078] In the embodiment of the present invention, the outer diameter of the feeding tube 2 is greater than 10 mm to prevent the dopant 4 from being unable to be added to the feeding barrel 1 due to being too small. The outer diameter of the feeding tube 2 is less than 100 mm to prevent the vaporized dopant 4 from flowing too slowly into the molten silicon during feeding, thereby ensuring that the vaporized dopant 4 can penetrate deeply into the molten silicon 800.

[0079] Specifically, the outer diameter of the feeding tube 2 can be 10 mm, 11 mm, 50 mm, 88 mm, 100 mm, etc.

[0080] Optionally, the wall thickness t1 of the cylinder 11 is greater than or equal to the wall thickness t2 of the feeding tube 2, and 2mm≤t1≤10mm.

[0081] In the embodiment of the present invention, the wall thickness t1 of the barrel 11 is greater than or equal to 2 mm, which can ensure the structural strength of the barrel 11 and avoid the risk of breakage of the feeding barrel 1. The wall thickness t1 of the barrel 11 is less than or equal to 10 mm, so that when heat conduction is performed, the feeding barrel 1 can ensure uniform heat conduction, and can avoid the generation of thermal stress and cracks during the doping process.

[0082] Furthermore, when the wall thickness of the cylinder 11 is equal to the wall thickness of the feeding pipe 2 , the processing difficulty of the feeding device 100 can be reduced.

[0083] Specifically, the wall thickness of the cylinder 11 can be 2mm, 5mm, 6mm, 7mm, 10mm, etc.

[0084] Optionally, the height of the feeding cylinder 1 in the direction from the first end 21 to the second end 22 is H3, and 100 mm ≤ H3 ≤ 300 mm.

[0085] In the embodiment of the present invention, the height of the feeding barrel 1 in the direction from the first end 21 to the second end 22 is less than or equal to 300 mm, which can avoid the low temperature of the feeding barrel 1 at one end of the first enclosure 12, prevent the dopant 4 from condensing on the inner wall of the feeding barrel 1, reduce the condensation amount of the dopant 4, and thus reduce the amount of dopant 4 attached to the inner wall of the feeding barrel 1. The height of the feeding barrel 1 in the direction from the first end 21 to the second end 22 is greater than or equal to 10 mm, which can avoid the height inside the feeding barrel 1 being too small, the dopant 4 being unable to enter the feeding barrel 1, and the resulting insufficient amount of dopant 4, ensuring that the feeding barrel 1 can accommodate

[0086] A sufficient amount of dopant 4 is added.

[0087] Specifically, the height of the feeding cylinder 1 in the direction from the first end 21 to the second end 22 can be 100 mm, 160 mm, 220 mm, 290 mm, 300 mm, etc.

[0088] Optionally, the height of the feeding pipe 2 in the direction from the first end 21 to the second end 22 is H2, and 130 mm ≤ H2 ≤ 360 mm.

[0089] In this embodiment of the present invention, the height of the feeding tube 2 along the direction from the first end 21 to the second end 22 is less than or equal to 360 mm. This prevents the dopant 4 from adhering to the inner wall of the feeding tube 2 due to the low temperature of the first end 21 due to its distance from the high-temperature environment during feeding. The height of the feeding tube 2 along the direction from the first end 21 to the second end 22 is greater than or equal to 130 mm, which ensures that sufficient dopant 4 can be added to the feeding barrel 1 at one time, thereby improving feeding efficiency.

[0090] Specifically, the height of the feeding pipe 2 in the direction from the first end 21 to the second end 22 can be 130 mm, 160 mm, 200 mm, 250 mm, 360 mm, etc.

[0091] Optionally, the length of the feeding tube 2 outside the feeding cylinder 1 is H1, 80mm≤H1≤150mm.

[0092] In the embodiment of the present invention, the length of the feeding tube 2 extending from the feeding barrel 1 is less than or equal to 150 mm. This prevents the feeding tube 2 from extending too long, thereby allowing it to be closer to the molten silicon 800, preventing damage to the feeding tube 2 at high temperatures, and allowing the feeding device 100 to be reused. The length of the feeding tube 2 extending from the feeding barrel 1 is greater than or equal to 80 mm, allowing the feeding tube 2 to extend sufficiently into the molten silicon 800. This prevents the vaporized dopant 4 from forming bubbles at the surface of the molten silicon 800 and being lost when the dopant 4 is introduced into and out of the feeding tube 2, thereby ensuring accurate addition of the dopant 4 gas.

[0093] Specifically, controlling the length of the feeding tube 2 extending outside the feeding barrel 1 within the range of 80mm-150mm can effectively ensure that the feeding tube 2 has sufficient length to extend into the molten silicon 800, thereby preventing the vaporized dopant 4 from forming bubbles on the liquid surface of the molten silicon 800 and being lost.

[0094] Specifically, the length of the feeding tube 2 extending out of the feeding cylinder 1 can be 80 mm, 90 mm, 100 mm, 115 mm, 132 mm, 150 mm, etc.

[0095] In one embodiment of the present invention, the length of the feeding tube 2 inside the feeding barrel 1 is H4, 50mm≤H4≤210mm.

[0096] By controlling the length H4 of the feeding tube 2 in the feeding barrel 1 within the above range, the dopant 4 can be smoothly fed in and out of the feeding barrel 1 while ensuring the material storage space in the feeding barrel 1.

[0097] 2 is located in the feeding barrel 1. The length is greater than or equal to 50 mm to prevent the added material from flowing out of the feeding tube 2; the length of the feeding tube 2 located in the feeding barrel 1 is less than or equal to 210 mm. If the feeding tube 2 is too long, the capacity of the material storage space will be affected; at the same time, it is prevented that the material cannot be added into the feeding barrel 1 from the feeding tube 2.

[0098] The feeding device in the embodiment of the present utility model has at least the following advantages:

[0099] In an embodiment of the present invention, the feeding barrel 1 has a material storage space, and the feeding tube 2 includes a first end 21 and a second end 22 opposite to each other, with the first end 21 located inside the feeding barrel 1 and the second end 22 located outside the feeding barrel 1. In this way, the dopant 4 can be added to the feeding barrel 1 through the feeding tube 2. When adding material, the side of the second end 22 of the feeding tube 2 away from the first end 21 is placed in the molten silicon 800, so that the vaporized dopant 4 is added to the molten silicon 800 along the enclosed space, avoiding losses caused by volatilization of the dopant 4 and effectively improving the yield of single crystal silicon wafers. The feeding device of the present invention has a simple structure. When used in the crystal growth process, since the dopant is added to the molten silicon through the feeding tube, losses caused by premature volatilization of the dopant are effectively prevented.

[0100] In a second aspect, an embodiment of the present invention further discloses a single crystal furnace, comprising a weight and the above-mentioned feeding device 100 .

[0101] Specifically, the feeding device 100 further includes a connecting member 3 ; the connecting member 3 is disposed outside the feeding barrel 1 , and the connecting member 3 can be connected to a side of the feeding barrel 1 away from the feeding pipe 2 , and the connecting member 3 is connected to the heavy hammer 200 .

[0102] In the embodiment of the present invention, the connecting member 3 can be connected to the weight 200, and doping can be achieved without additional connecting components.

[0103] Specifically, the connecting member 3 and the second enclosure 13 can be fixed by bonding or welding. Among them, the connecting member 3 and the second enclosure 13 are fixed by welding, which can improve the convenience of connecting the connecting member 3 and the feeding barrel 1 and improve the reliability of the connection between the connecting member 3 and the feeding barrel 1.

[0104] Specifically, the single crystal furnace includes a pulling mechanism for crystal growth. The pulling mechanism is connected to a weight 200, which is used to connect to the seed crystal. The pulling head drives the seed crystal connected to the weight to pull the single crystal silicon rod. In this embodiment of the utility model, before pulling the crystal, the connecting member 3 can be connected to the weight 200, so that the feeding device 100 and the seed crystal can share a set of transmission mechanisms.

[0105] Specifically, if Figure 4 and Figure 5 As shown, the weight 200 can be connected to the connecting member 3.

[0106] Optionally, the connecting member 3 is provided with a mounting hole 31 so as to facilitate connection of the weight 200 through the mounting hole 31 .

[0107] Specifically, the mounting hole 31 may penetrate the connector 3 along a first direction, and the first direction may intersect with the direction from the first end 21 to the second end 22 , thereby improving the reliability of connecting the connector 3 to the weight 200 .

[0108] Specifically, the connecting member 3 and the weight 200 can be detachably connected by a pin, or can be detachably connected by a bolt.

[0109] Specifically, if Figure 5 As shown, the feeding device 100 is applied in the process of pulling single crystal silicon rods. The furnace body 300 of the single crystal furnace is provided with a guide tube 400, a heater 500, an insulation tube 600, a crucible 701, a crucible side 702 and a drag rod 703.

[0110] The feeding device 100 can be connected to the weight 200 via the connecting member 3, and the driving member can drive the feeding device 100 to rise or fall via the weight 200. When adding the dopant 4, the driving member can drive the feeding device 100 to fall, so that the feeding device 100 can pass through the guide tube 400 and stop above the crucible 701, and the end of the second end 22 of the feeding tube 2 away from the first end 21 can be inserted into the molten silicon 800.

[0111] When feeding, the feeding device 100 descends to above the liquid level of the main chamber and continues to descend so that the second end 22 of the feeding tube 2 is inserted into the molten silicon 800 away from the end of the first end 21, and the depth of the feeding tube 1 in the molten silicon 800 can be judged based on the reflection of the feeding tube 1 in the silicon liquid, so as to avoid the feeding tube 1 being immersed in the silicon liquid and the feeding tube 1 being corroded by the silicon liquid. Since the liquid surface temperature of the molten silicon 800 is as high as 1000°, the dopant 4 in the feeding tube 1 is vaporized and added to the molten silicon 800 along with the feeding tube 2. Since the feeding device 100 has a material storage space and is sealed, the vaporized dopant 4 is eventually added to the molten silicon 800 due to the pressure difference between the feeding tube 1 and the single crystal furnace. After the feeding is completed, the feeding device 100 can be removed and the feeding device 100 can be recycled.

[0112] The dopant 4 is added to the molten silicon 800 by using the feeding device 100 in the embodiment of the present invention. The process is simple, and the feeding device 100 has a simple structure and a simple preparation method.

[0113] Specifically, the feeding device 100 in the embodiment of the present invention is used to replace the feeding device 100 in the prior art. When the dopant 4 is added to the molten silicon 800, the loss of the dopant 4 can be reduced to 0.

[0114] With a reduction of 15.38%, the doping hit rate can be improved by 26%.

[0115] The single crystal furnace described in the embodiment of the present utility model has at least the following advantages:

[0116] In an embodiment of the present utility model, the feeding barrel 1 has a material accommodating space, and the feeding tube 2 includes a first end 21 and a second end 22 relative to each other. The first end 21 is located inside the feeding barrel 1, and the second end 22 is located outside the feeding barrel 1. In this way, the dopant 4 can be added to the feeding barrel 1 through the feeding tube 2; when adding material, the side of the second end 22 of the feeding tube 2 away from the first end 21 is placed in the molten silicon 800, so that the vaporized dopant 4 is added to the molten silicon 800 along the enclosed space, avoiding the loss caused by the volatilization of the dopant 4, and effectively improving the yield of single crystal silicon wafers.

[0117] The feeding device of the utility model has a simple structure. When used in the crystal growth process, since the dopant is added into the molten silicon through the feeding pipe, the loss caused by premature volatilization of the dopant is effectively prevented.

[0118] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0119] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or terminal device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or terminal device that includes the element.

[0120] The above is a detailed introduction to a feeding device and a single crystal furnace provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for general technical personnel in this field, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A feeding device (100), characterized in that: include: A feeding cylinder (1), wherein the feeding cylinder (1) has a material storage space; A feeding tube (2), comprising a first end portion (21) and a second end portion (22) opposite to each other, wherein the first end portion (21) is located inside the feeding barrel (1) and the second end portion (22) is located outside the feeding barrel (1); the feeding tube guides the substance to be added into or out of the material holding space.

2. The feeding device (100) according to claim 1, characterized in that The feeding cylinder (1) comprises a cylinder (11) and a first enclosing portion (12) and a second enclosing portion (13) arranged at two ends of the cylinder (11) relative to each other, wherein the cylinder (11), the first enclosing portion (12) and the second enclosing portion (13) enclose and form the material storage space; The feeding pipe (2) is arranged through the first enclosure (12), and the first end (21) is spaced apart from the second enclosure (13) on a side away from the second end (22), and the first end (21) is spaced apart from the cylinder (11).

3. The feeding device (100) according to claim 1, characterized in that The length of the feeding pipe (2) outside the feeding cylinder (1) is H1, 80mm≤H1≤150mm.

4. The feeding device (100) according to claim 3, characterized in that The height of the feeding pipe (2) in the direction from the first end to the second end is H2, and 130 mm ≤ H2 ≤ 360 mm.

5. The feeding device (100) according to any one of claims 1 to 4, characterized in that: The length of the feeding pipe (2) inside the feeding cylinder (1) is H4, 50mm≤H4≤210mm.

6. The feeding device (100) according to claim 2, characterized in that The wall thickness t1 of the cylinder (11) is greater than or equal to the wall thickness t2 of the feeding tube (2), and 2mm≤t1≤10mm.

7. The feeding device (100) according to claim 2, characterized in that The height of the feeding cylinder (1) in the direction from the first enclosing portion (12) to the second enclosing portion (13) is H3, and 100mm≤H3≤300mm.

8. The feeding device (100) according to claim 2, characterized in that The outer diameter of the cylinder (11) is D1, 100mm≤D1≤200mm; the outer diameter of the feeding pipe (2) is D2, 10mm<D2<100mm.

9. The feeding device (100) according to claim 1, characterized in that The cross-sectional shape of the feeding pipe (2) along the direction from the first end (21) to the second end (22) is a straight line or a curved line.

10. A single crystal furnace, characterized in that: It comprises a weight hammer and a feeding device (100) according to any one of claims 1 to 9, wherein the feeding device (100) further comprises a connecting member (3); The connecting piece (3) is connected to the side of the feeding cylinder (1) facing away from the feeding pipe (2). When feeding, the connecting piece (3) is connected to the heavy hammer.

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