Continuous Czochralski single crystal furnace and monocrystalline silicon production process

Abstract

The invention belongs to the technical field of single crystal furnaces, and particularly discloses a continuous Czochralski single crystal furnace and a monocrystalline silicon production process. Comprising a single crystal furnace and a feeding device, the single crystal furnace comprises a furnace body, a furnace cover and a thermal field arranged in the furnace body, the feeding device comprises a base, a support, a stock bin, a material control mechanism and a material conveying pipe, the single crystal furnace is communicated with the feeding device through the material conveying pipe, a gate valve is arranged between the single crystal furnace and the feeding device, and the gate valve is connected with the base. And the isolation device is used for isolating the single crystal furnace from the feeding equipment. According to the invention, the production efficiency and quality of the monocrystalline silicon are improved by improving the thermal field design, the feeding mechanism, the splash-proof measure and the overall production process, and through the improvement, the problem of non-uniform resistivity can be effectively solved, so that the quality of the monocrystalline silicon, the efficiency of a battery piece and the production efficiency of the monocrystalline silicon are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of single crystal furnaces, and specifically discloses a continuous vertical pulling single crystal furnace and a single crystal silicon production process. Background Art

[0002] With the rapid development of the photovoltaic industry, the conversion efficiency of photovoltaic cells has made new breakthroughs, and the market's quality requirements for monocrystalline silicon wafers are getting higher and higher. The resistivity of monocrystalline silicon has an important impact on the power generation efficiency of the cell, especially in a certain range of monocrystalline cells with more concentrated resistivity can show higher efficiency, so the concentration of resistivity has become the focus of industry attention, and the mainstream production method of monocrystalline silicon is RCZ (Recharge Czochralski) multiple feeding direct pulling technology. This technology requires adding polysilicon and dopants to the crucible through a feeder multiple times during the production process, and after the crucible is full, the melting and seeding processes begin. However, during the production process, as the melt in the crucible gradually decreases, due to the influence of the segregation coefficient, the impurities in the melt will be unevenly distributed, resulting in a wider resistivity range for the final product, affecting the overall efficiency of the cell.

[0003] The patent application number is CN201110199181.1, which is a production process of direct-pulled silicon single crystals, comprising the following steps: 1. Preparation of silicon raw materials and dopants; 2. Loading; 3. Vacuuming treatment; 4. Melting material; 5. Slag extraction after melting the material, and the slag extraction process is as follows: 501. Cooling and crystallization; 502. Gradually heating and maintaining the crystallization process continuously until all the insolubles floating on the surface of the silicon melt are condensed by the crystals; 503. Slag removal after crystallization; 6. Subsequent treatment: using a single crystal furnace and following the conventional processing process of the direct-pulling method, the seeding, shoulder release, shoulder rotation, equal diameter, finishing and furnace shutdown processes are completed in sequence, and the drawn silicon single crystal product is obtained. The single crystal furnace production cost of the above process is high, and the production quality of single crystal silicon cannot be ensured. Therefore, it is urgent for those skilled in the art to solve the above technical problems. Summary of the invention

[0004] The technical problem to be solved by the present invention is that in the above-mentioned prior art, the production cost of the single crystal furnace is high and the production quality of single crystal silicon cannot be ensured.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A continuous Czochralski single crystal furnace, comprising a single crystal furnace and a charging device;

[0007] The single crystal furnace comprises a furnace body, a furnace cover and a heat field disposed in the furnace body;

[0008] The feeding equipment includes a base, a bracket, a silo, a material control mechanism and a material conveying pipe;

[0009] The single crystal furnace is connected to the feeding device through the feeding pipeline, and a gate valve is provided between the single crystal furnace and the feeding device to isolate the single crystal furnace from the feeding device.

[0010] Furthermore, the heat field is composed of an outer heat preservation cylinder and a quartz crucible placed at the center of the heat field, the bottom of the quartz crucible is supported by a supporting rod, a water cooling device is provided above the quartz crucible, and a guide cylinder is provided outside the water cooling device;

[0011] The thermal field includes top insulation, guide tube support ring, upper insulation tube, middle insulation tube and furnace bottom insulation;

[0012] The outer side of the quartz crucible is provided with a main heater, the bottom is provided with a bottom heater, and the water cooling device is connected to the furnace cover;

[0013] An isolation ring is installed below the guide tube;

[0014] A feed pipe is provided between the isolation ring and the quartz crucible, the feed pipe passes through the guide tube support ring, the top insulation and the feeding pipe, a feed pipe sheath is provided on the outside of the feed pipe, the feeding pipe is placed in the solid felt support block, and the top of the feeding pipe is connected to the furnace cover feeding port.

[0015] Further, the quartz crucible has a height not exceeding 500 mm and a diameter not less than 36 inches;

[0016] The top insulation is in a circular ring structure, and a circular hole through which the feed pipe passes is provided on one side of the top insulation, and a positioning hole is provided at a corresponding horizontal position;

[0017] A circular hole is provided on one side of the guide tube support ring for the feed pipe to pass through, and threaded holes are evenly distributed around the circular hole for installing the feed pipe sheath;

[0018] The height of the heating zone of the main heater is between 180-220 mm, matching the quartz crucible;

[0019] The lower opening of the guide tube is provided with a connecting ring;

[0020] The isolation ring is provided with a mounting hole on its upper edge and a vent hole on its side wall. The vent hole is circular or square in shape. The circumferential arc length of the vent hole is not less than 1 / 2 of the circumference of the isolation ring. The distance between the edge of the vent hole and the lower end of the isolation ring is not less than 30 mm.

[0021] The feed pipe is a straight cylindrical tube with a trumpet-shaped stopper at the upper end;

[0022] The upper and lower sections of the feeding pipe are straight cylindrical round tubes, and the middle section is an inclined straight cylindrical round tube for raw material buffering. The upper and lower sections of the feeding pipe are connected with the middle section. A trumpet-shaped stop is provided on the top of the feeding pipe, which is connected to the feeding funnel;

[0023] The material pipe sheath is made of graphite or carbon ceramic high temperature resistant material, in the form of a straight cylindrical round tube, placed outside the feed pipe, with a flange interface on the top, installed with the guide tube support ring, and a step on the inner diameter at the bottom for supporting the feed pipe.

[0024] Furthermore, the felt support block is a trapezoidal two-petal structure, with a positioning block at the rear end, which cooperates with the positioning hole, and a groove matching the feeding tube is provided inside, which covers the feeding tube, is inserted into the feeding tube and fixed with a screw.

[0025] Furthermore, the lower end of the feeding funnel is in a straight cylindrical shape, which cooperates with the upper end of the feeding pipe, and the upper end of the feeding funnel is in a trumpet shape, which is connected to the conveying pipe.

[0026] Furthermore, the base is rectangular and is placed on one side of the single crystal furnace. A slide rail and a driving device are provided above the base. The bracket can move on the slide rail. The silo is provided above the bracket. The material control mechanism is provided at the discharge port below the silo. The material control mechanism is connected to the silo discharge port at the top and to the feed pipe at the side. The outer side of the feed pipe is a corrugated pipe, which connects the single crystal furnace and the feeding device.

[0027] The material control mechanism interface and the material delivery channel deliver the raw materials in the material bin to the material delivery pipe through vibration. After the raw materials are delivered to the feeding funnel along the material delivery pipe, the raw materials fall freely and fall into the quartz crucible along the feeding pipe and the discharge pipe.

[0028] The silo is a sealed structure, and the interior of the silo is in a vacuum state during the production process.

[0029] The present invention also includes a continuous Czochralski silicon single crystal production process, which uses the above-mentioned continuous Czochralski single crystal furnace to carry out single crystal furnace production, and the production of single crystal silicon includes the following steps:

[0030] Melt: main heater power 60-80KW, crucible position 0-50mm;

[0031] Temperature adjustment and welding: When heating, the main power is 70KW. When rapid heating is required, the bottom heater is turned on, and the power is not higher than 30KW. When pulling the temperature, the minimum power of the main heater is 10KW lower than the seeding power. When the temperature starts to drop and is 10°C away from the target value, it is restored to the seeding power. After the temperature reaches the target value, the temperature stabilization time is not less than 40 minutes;

[0032] The constant crucible rotation crystal pulling process is adopted, and the crucible rotation is 2-4 revolutions per minute;

[0033] Seeding: Seeding starts after welding is completed, and the average seeding speed is 280mm / h;

[0034] Shoulder release: The initial temperature drop is large. As the shoulder length increases, the temperature drop gradually decreases. The power change law is a logarithmic curve. The final temperature drop is 7.6KW, matching a 10-inch single crystal rod.

[0035] Equal diameter: During the equal diameter process, quantitative feeding is adopted to achieve stable growth of single crystal through automatic adjustment of power and pulling speed. The feeding amount matches the growth speed set by the process. The growth speed setting range is 100mm / h, which matches 10-inch single crystal rod;

[0036] The feed rate is 195 g / min. The actual growth rate during the equal diameter process fluctuates with the melt temperature. The feed rate is a fixed feed rate that matches the growth rate setting value.

[0037] Finishing: After the single crystal grows to the set length, it automatically enters the finishing process. As the finishing length increases, the crystal diameter shrinks, and the amount of material added gradually decreases until the finishing is completed. The feeding is stopped and the next stage of temperature adjustment begins after the finishing is completed. The crystal rod taking time is 1 hour, which overlaps with the temperature adjustment time to improve time utilization.

[0038] Furthermore, the feeding device comprises the following steps when in use:

[0039] Positioning of the feeding equipment: After the single crystal furnace is installed, the bracket is moved to the feeding position, the base is adjusted, the feeding pipe is aligned with the feeding funnel, and the base is fixed;

[0040] Reset the feeding device: After the base is fixed, move the bracket to the initial position, and the main chamber can be opened normally without interfering with the feeding device;

[0041] Docking of feeding equipment: after the heat field is installed and the production conditions are met, the bracket is moved to the feeding position, and the bellows is docked and installed with the gate valve. Before installation, clean the installation surface to ensure sealing;

[0042] The charging equipment does not need to be moved during the entire production process. When the furnace is shut down and disassembled, the bellows and the gate valve are disassembled, the charging equipment is reset, the main chamber is unscrewed and disassembled, and after the hot field is installed and the production conditions are met, the charging equipment is reconnected to continue production.

[0043] The present invention has the following beneficial effects:

[0044] The present invention reduces the manufacturing cost of the single crystal furnace by lowering the thermal field structure and lowering the height of the main furnace chamber of the single crystal furnace. By adopting the CCZ continuous vertical pulling technology, it is possible to add materials while pulling crystals, thereby maintaining the constant weight of the melt and the resistivity of the melt in the crucible, and effectively solving the problem of uneven impurity distribution caused by the reduction of the melt, thereby making the resistivity of the produced single crystal silicon rods more concentrated and improving the efficiency of the battery cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a structural schematic diagram of the single crystal furnace of the present invention.

[0046] Figure 2 It is a structural schematic diagram of the thermal field of the present invention.

[0047] Figure 3 It is a structural schematic diagram of the feeding equipment of the present invention.

[0048] Figure 4 It is a schematic structural diagram of the top insulation of the present invention.

[0049] Figure 5 It is a structural schematic diagram of the guide tube of the present invention.

[0050] Figure 6 It is a structural schematic diagram of the circular hole of the isolation ring of the present invention.

[0051] Figure 7 It is a structural schematic diagram of the square hole of the isolation ring of the present invention.

[0052] Figure 8 It is a curve diagram of the temperature reduction amount and the feeding amount of the shoulder release of the present invention.

[0053] Fig. 9 It is a curve diagram of the constant diameter growth rate and the feed amount of the present invention.

[0054] Fig.10 It is a curve diagram of the end length and the amount of feed of the present invention.

[0055] Among them are: 1-single crystal furnace; 101-round hole; 102-positioning hole; 2-feeding equipment; 201-base; 202-bracket; 203-bin; 204-material control mechanism; 205-feeding pipe; 3-furnace cover; 4-heat field; 5-gate valve; 6-quartz crucible; 7-support rod; 8-water cooling device; 9-guide tube; 901-connecting ring; 10-top insulation; 11-guide tube support ring; 12-upper insulation tube; 13-middle insulation tube; 14-furnace bottom insulation; 15-main heater; 16-bottom heater; 17-isolation ring; 18-down pipe; 19-feeding pipe; 20-pipe sheath; 21-solid felt support block; 22-feeding funnel. DETAILED DESCRIPTION

[0056] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific preferred embodiments.

[0057] In the description of the present invention, it should be understood that the terms "left side", "right side", "upper part", "lower part" 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 present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. "First", "second" and the like do not indicate the importance of the components, and therefore cannot be understood as limiting the present invention. The specific dimensions used in this embodiment are only for illustrating the technical solution, and do not limit the scope of protection of the present invention.

[0058] Embodiment 1: The existing single crystal furnace 1 cannot realize continuous Czochralski production of single crystal silicon, and the manufacturing cost of the single crystal furnace 1 is high, but the production efficiency is low. Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 It can be seen that a continuous Czochralski single crystal furnace includes a single crystal furnace 1, the single crystal furnace 1 includes a furnace body for accommodating a thermal field 4 and other components, a furnace cover 3 covering the top of the furnace body for sealing the furnace body, and a charging port is also provided on the furnace cover 3, which is located in the furnace body and is used to control the temperature distribution of the thermal field 4 during the crystal growth process;

[0059] The feeding device 2 includes a base 201, a bracket 202, a material bin 203 and a material control mechanism 204;

[0060] The base 201 is located at one side of the single crystal furnace 1 and is used to support the entire charging device 2;

[0061] The bracket 202 is located above the base 201 and can be moved by a slide rail;

[0062] The silo 203 is placed above the support 202 and is used to store raw materials;

[0063] The material control mechanism 204 is located at the discharge port below the silo 203 and is used to control the output of the raw materials.

[0064] The feeding pipe 205 connects the charging device 2 and the single crystal furnace 1, and the outer side is a bellows to accommodate the relative movement between the furnace body and the charging device;

[0065] The hot field 4 components include an outer heat preservation tube, a quartz crucible 6, a support rod 7, a water cooling device 8, a guide tube 9, an isolation ring 17, a feed pipe 18, a feed pipe 19 and a feed pipe jacket 20;

[0066] The outer heat preservation tube is arranged around the quartz crucible 6 for heat preservation;

[0067] The quartz crucible 6 is located at the center of the heat field 4, and the bottom is supported by a supporting rod 7;

[0068] The support rod 7 is used to support the bottom of the quartz crucible 6;

[0069] The water cooling device 8 is located above the quartz crucible 6 and is used for cooling;

[0070] The guide tube 9 is located outside the water cooling device 8, and a connecting ring 901 is installed in the guide tube 9. The connecting ring 901 is used to be compatible with single crystal silicon rods of 10 inches, 11 inches or 12 inches;

[0071] The isolation ring 17 is located below the guide tube 9, and a feed pipe 18 is provided between the isolation ring 17 and the quartz crucible 6;

[0072] The feed pipe 18 passes through the guide tube support ring 11, the top insulation 10 and is connected to the feed pipe 19;

[0073] The feeding pipe 19 is used to guide the raw materials into the quartz crucible 6;

[0074] The material pipe sheath 20 is located outside the material pipe 18 and is used to protect the material pipe 18;

[0075] In addition, the single crystal furnace 1 also includes a top heat preservation 10 in a circular ring structure, which is provided with a circular hole 101 for the feeding pipe 18 to pass through;

[0076] The guide tube support ring 11 is used to support the guide tube 9 and is provided with a circular hole 101 for the discharge pipe 18 to pass through;

[0077] The upper insulation tube 12, the middle insulation tube 13 and the furnace bottom insulation 14 constitute the insulation layer of the thermal field 4;

[0078] The main heater 15 and the bottom heater 16 are used to heat the inside and outside of the quartz crucible 6;

[0079] The felt support block 21 is used to fix the feeding pipe 19;

[0080] The feeding funnel 22 is connected to the feeding pipe 19 and is used to receive the raw materials;

[0081] By setting the height of the quartz crucible 6 to not more than 500 mm and the diameter to not less than 36 inches, the production cost is reduced. The height of the heating zone of the main heater 15 is set between 180 mm and 220 mm to match the quartz crucible 6 for easy processing. The upper and lower sections of the feeding pipe 19 are straight cylindrical tubes, and the middle part is an inclined straight cylindrical tube for raw material buffering. The material pipe sheath 20 is made of graphite or carbon ceramic high temperature resistant material to protect the feeding pipe 18;

[0082] In actual use, the raw materials are transported from the silo 203 to the feeding funnel 22 through the material control mechanism 204 and the feeding pipe 205, and then fall into the quartz crucible 6 through the feeding pipe 19 and the discharge pipe 18. During the feeding process, the gate valve 5 is used to isolate the single crystal furnace 1 from the feeding equipment 2 to ensure the safety and controllability of the production process. The device realizes the continuous production of single crystal silicon rods and the concentration of resistivity by improving the thermal field structure, the feeding mechanism and the raw material transportation method, thereby improving the production efficiency and the quality of single crystal silicon.

[0083] Example 2: In the existing production of single crystal silicon, the finished product efficiency is low and the production cycle is slow. Therefore, in order to improve the production efficiency of single crystal silicon, Figure 8 , Fig. 9 and Fig.10 It can be seen that a continuous Czochralski silicon single crystal production process is proposed, comprising the following steps:

[0084] Positioning of the feeding device 2: After the single crystal furnace 1 is installed, the bracket 202 is moved to the feeding position, the base 201 is adjusted, the feeding pipe 205 is aligned with the feeding funnel 20, and the base 201 is fixed;

[0085] Reset the feeding device 2: After the base 201 is fixed, move the bracket 202 to the initial position, and the main chamber can be opened normally without interfering with the feeding device 2;

[0086] Docking of feeding equipment 2: After the hot field 4 is installed and the production conditions are met, the bracket 202 is moved to the feeding position, and the bellows and the gate valve 5 are docked and installed. Before installation, clean the installation surface to ensure sealing;

[0087] The charging device 2 does not need to be moved during the entire production process. When the furnace is shut down and disassembled, the bellows and the gate valve 5 are disassembled, the charging device 2 is reset, the main chamber is unscrewed and disassembled, and after the hot field 4 is installed and the production conditions are met, the charging device 2 is reconnected to continue production;

[0088] Then, the melting, temperature adjustment, welding, seeding, shouldering, equalizing the diameter and finishing are carried out.

[0089] Melt: The power of the main heater is 70KW, and the crucible position is 50mm; the isolation ring 17 is located above the molten silicon and is in the high temperature area. If the power of the main heater is too high and overheated, the isolation ring will soften and deform. The purpose of the crucible position being greater than zero is to block the heat of the main heater and avoid direct radiation of the isolation ring from the high temperature area of ​​the main heater. The purpose of the crucible position being less than 50mm is to avoid interference between the material tube jacket and the raw material. In order to load as much raw material as possible in the crucible, the crucible position should be as low as possible without interference between the raw material and the material tube jacket.

[0090] Temperature adjustment and welding: When heating, the main power is 70KW. When rapid heating is required, the bottom heater is turned on with a power of 30KW. When pulling the temperature, the minimum power is 10KW lower than the seeding power. The temperature starts to drop and returns to the seeding power when it is 10°C away from the target value. After the temperature reaches the target value, the temperature stabilization time is not less than 40 minutes. The constant crucible-to-crystal pulling process is adopted, and the crucible is rotated at 3 rpm. When the melt temperature is low and rapid heating is required, the main heater power of 70KW does not meet the heating conditions, and the bottom heater 16 needs to be turned on to increase the heat. If the temperature of the bottom heater 16 is too high, the oxygen content in the melt will increase. Therefore, the power of the bottom heater 16 should be controlled within 30KW.

[0091] Seeding: Seeding begins after welding is completed, with an average seeding speed of 280 mm / h. Too fast or too slow a seeding speed will result in insufficient elimination of single crystal dislocations, affecting the quality of the single crystal.

[0092] Shoulder release: The initial temperature drop is large, and as the shoulder length increases, the temperature drop gradually decreases, and the power change law is a logarithmic curve. The final temperature drop is 7.6KW. The product specification of this embodiment is 10-inch crystal rod;

[0093] Furthermore, feeding begins during the shoulder release process. When the shoulder length is 50 mm, the feeding equipment is started to feed, and the starting feeding amount is 30 g / min. The starting feeding amount is set to 30 g / min, and the feeding amount is relatively low. The purpose is that in the initial stage of starting the feeding equipment, the raw material output is unstable. When the feeding amount reaches 30 g / min, the raw material can be stably output according to the set feeding speed. As the shoulder length increases, the crystal diameter increases, and the feeding amount gradually increases.

[0094] Equal diameter: During the equal diameter process, quantitative feeding is used, which is beneficial to the stability of the melt temperature. The stable growth of single crystal is achieved through automatic adjustment of power and pulling speed. The feeding amount matches the growth speed set by the process. The growth speed is set to 100mm / h; the feeding amount is 195g / min; during the equal diameter process, the actual growth speed fluctuates with the melt temperature, and the feeding amount is a fixed feeding speed, matching the growth speed setting value.

[0095] During the equal diameter growth process, when the melt temperature is low, the actual growth rate increases. When it exceeds the set growth rate, the relative feed amount is low, the melt temperature will gradually increase, and the actual growth rate returns to the set rate; when the melt temperature is high, the actual growth rate decreases. When it is lower than the set growth rate, the relative feed amount is high, the melt temperature will gradually decrease, and the actual growth rate returns to the set rate;

[0096] Finishing: After the single crystal grows to the set length, it automatically enters the finishing process. As the finishing length increases, the crystal diameter decreases, and the feeding amount gradually decreases until the finishing is completed and the feeding stops;

[0097] Furthermore, after finishing, the next stage of temperature adjustment begins. The time for taking the crystal rod is 1 hour, which overlaps with the temperature adjustment time, thereby improving time utilization.

[0098] The preferred embodiments of the present invention are described in detail above; however, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all belong to the protection scope of the present invention.

Claims

1. A continuous Czochralski single crystal furnace, characterized in that: It comprises a single crystal furnace (1) and a charging device (2); The single crystal furnace (1) comprises a furnace body, a furnace cover (3) and a heat field (4) arranged in the furnace body; The feeding device (2) comprises a base (201), a bracket (202), a material bin (203), a material control mechanism (204) and a material conveying pipe (205); The single crystal furnace (1) is connected to the feeding device (2) via the feeding pipeline (205), and a gate valve (5) is provided between the single crystal furnace (1) and the feeding device (2) for isolating the single crystal furnace (1) from the feeding device (2).

2. The continuous Czochralski single crystal furnace according to claim 1, characterized in that: The heat field (4) is composed of an outer heat preservation tube and a quartz crucible (6) placed at the center of the heat field (4); the bottom of the quartz crucible (6) is supported by a supporting rod (7); a water cooling device (8) is provided above the quartz crucible (6); and a guide tube (9) is provided outside the water cooling device (8); The thermal field (4) comprises a top insulation (10), a guide tube support ring (11), an upper insulation tube (12), a middle insulation tube (13) and a furnace bottom insulation (14); The outer side of the quartz crucible (6) is provided with a main heater (15), the bottom is provided with a bottom heater (16), and the water cooling device (8) is connected to the furnace cover (3); An isolation ring (17) is installed below the guide tube (9); A feed pipe (18) is provided between the isolation ring (17) and the quartz crucible (6); the feed pipe (18) passes through the guide tube support ring (11), the top insulation (10) and is connected to a feed pipe (19); a feed pipe sheath (20) is provided on the outside of the feed pipe (18); the feed pipe (19) is placed in a solid felt support block (21); and the top of the feed pipe (19) is connected to a feed port of the furnace cover (3).

3. The continuous Czochralski single crystal pulling furnace according to claim 2, characterized in that: The quartz crucible (6) has a height not exceeding 500 mm and a diameter not less than 36 inches; The top insulation (10) is in the form of a circular ring structure, and a circular hole (101) through which the feed pipe (18) passes is provided on one side of the top insulation (10), and a positioning hole (102) is provided at a corresponding horizontal position; The circular hole (101) through which the feed pipe (18) passes is provided on one side of the guide tube support ring (11), and threaded holes evenly distributed around the circular hole (101) are provided for mounting a feed pipe sheath (20); The height of the heating zone of the main heater (15) is between 180-220 mm, matching the quartz crucible (6); The lower opening of the guide tube (9) is provided with a connecting ring (901); The isolation ring (17) is provided with a mounting hole (171) on its upper edge, and a vent hole (172) is provided on its side wall. The vent hole (172) is circular or square, and the circumferential arc length of the vent hole (172) is not less than 1 / 2 of the circumference of the isolation ring (17). The distance between the edge of the vent hole (172) and the lower end of the isolation ring (17) is not less than 30 mm. The feed pipe (18) is a straight cylindrical tube with a trumpet-shaped stopper at the upper end; The upper and lower sections of the feeding pipe (19) are straight cylindrical round tubes, and the middle section is an inclined straight cylindrical round tube for raw material buffering. The upper and lower sections of the feeding pipe (19) are connected to the middle section. A trumpet-shaped stop is provided above the feeding pipe (19) and is connected to the feeding funnel (22); The material pipe sheath (20) is made of graphite or carbon ceramic high temperature resistant material and is in the form of a straight cylindrical round tube. It is placed outside the material discharge pipe (18) and has a flange interface at the top for installation with the guide tube support ring (11). The inner diameter at the bottom is provided with a step for supporting the material discharge pipe (18).

4. The continuous Czochralski single crystal furnace according to claim 2, characterized in that: The felt support block (21) is a trapezoidal two-petal structure, with a positioning block at the rear end, which cooperates with the positioning hole (102), and a groove matching the feeding tube (19) is provided inside, which covers the feeding tube (19), is inserted into the feeding tube (19), and is fixed with a screw.

5. The continuous Czochralski single crystal furnace according to claim 3, characterized in that: The lower end of the feeding funnel (22) is in a straight cylindrical shape and cooperates with the upper end of the feeding pipe (19). The upper end of the feeding funnel (22) is in a trumpet shape and butts with the conveying pipe (205).

6. The continuous Czochralski single crystal pulling furnace according to claim 1, characterized in that: The base (201) is rectangular and is placed on one side of the single crystal furnace (1). A slide rail and a driving device are provided above the base (201). The bracket (202) can move on the slide rail. The material bin (203) is provided above the bracket (202). The material control mechanism (204) is provided at the discharge port below the material bin (203). The material control mechanism (204) is connected to the discharge port of the material bin (203) at the top and to the material delivery pipe (205) at the side. The outer side of the material delivery pipe (205) is a corrugated pipe, which connects the single crystal furnace (1) and the feeding device (2); The interface of the material control mechanism (204) and the material delivery channel deliver the raw materials in the material bin (203) to the material delivery pipe (205) through vibration. After the raw materials are delivered to the feeding funnel (22) along the material delivery pipe (205), the raw materials fall freely and fall into the quartz crucible (6) along the feeding pipe (19) and the discharge pipe (18); The material bin (203) is a sealed structure, and the interior of the material bin (203) is in a vacuum state during the production process.

7. A continuous Czochralski silicon single crystal production process, comprising the continuous Czochralski single crystal furnace according to any one of claims 1 to 6, characterized in that: The production of single crystal silicon includes the following steps: Melt: main heater power 60-80KW, crucible position 0-50mm; Temperature adjustment and welding: when heating, the main power is not higher than 70KW. When rapid heating is required, the power of the bottom heater (16) is less than 30KW. When pulling the temperature, the minimum power of the main heater (15) is 10KW lower than the seeding power. When the temperature starts to drop and is 10°C away from the target value, the seeding power is restored and the bottom heater (16) is turned off. After the temperature reaches the target value, the temperature stabilization time is not less than 40 minutes. The constant crucible rotation crystal pulling process is adopted, and the crucible rotation is 2-4 revolutions per minute; Seeding: Seeding begins after welding is completed, and the average seeding speed range is 260-280mm / h; Shoulder release: The initial temperature drop is large, and as the shoulder length increases, the temperature drop gradually decreases. The power change law is a logarithmic curve. The final temperature drop range is 6-10KW, which is determined according to the specifications of the crystal rod; Equal diameter: During the equal diameter process, quantitative feeding is adopted, and the stable growth of single crystal is achieved through automatic adjustment of power and pulling speed. The feeding amount matches the growth speed set by the process. The growth speed setting range is 90-110mm / h, which is determined according to the specifications of the crystal rod; The feed rate range is 180-300g / min. The actual growth rate during the equal diameter process fluctuates with the melt temperature. The feed rate is a fixed feed rate that matches the growth rate setting value. Finishing: After the single crystal grows to the set length, it automatically enters the finishing process. As the finishing length increases, the crystal diameter shrinks, and the amount of material added gradually decreases until the finishing is completed. The feeding is stopped and the next stage of temperature adjustment begins after the finishing is completed. The crystal rod taking time is 1 hour, which overlaps with the temperature adjustment time to improve time utilization.

8. A continuous Czochralski silicon single crystal production process according to claim 7, characterized in that: The feeding device (2) comprises the following steps when in use: Positioning of the feeding device (2): after the single crystal furnace (1) is installed, the support (202) is moved to the feeding position, the base (201) is adjusted, the feeding pipe (205) is aligned with the feeding funnel (20), and the base (201) is fixed; Resetting the feeding device (2): after the base (201) is fixed, the bracket (202) is moved to the initial position, and the main chamber can be normally opened without interfering with the feeding device (2); Docking of the feeding equipment (2): After the heat field (4) is installed and the production conditions are met, the bracket (202) is moved to the feeding position, and the bellows and the gate valve (5) are docked and installed. Before installation, the installation surface is cleaned to ensure sealing; The charging device (2) does not need to be moved during the entire production process. When the furnace is shut down and disassembled, the bellows and the gate valve (5) are disassembled and separated, the charging device (2) is reset, the main chamber is unscrewed and disassembled, and after the heat field (4) is installed and the production conditions are met, the charging device (2) is reconnected and production continues.

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