CN113622026A

CN113622026A - Czochralski single crystal re-feeding device and re-feeding method thereof

Info

Publication number: CN113622026A
Application number: CN202010371143.9A
Authority: CN
Inventors: 吴树飞; 王林; 高润飞; 谷守伟; 王建平; 周泽; 杨志; 赵国伟; 刘振宇; 郝瑞军; 刘学; 皇甫亚楠; 杨瑞峰; 郭志荣; 钟旭
Original assignee: Inner Mongolia Zhonghuan Solar Material Co Ltd
Current assignee: Inner Mongolia Zhonghuan Solar Material Co Ltd
Priority date: 2020-05-06
Filing date: 2020-05-06
Publication date: 2021-11-09

Abstract

The invention provides a czochralski single crystal re-casting device, which comprises a cylinder body, a quartz umbrella, a molybdenum rod, a supporting component, a monitoring component and a fixing component, wherein the supporting component is used for supporting the cylinder body, the monitoring component is used for detecting the whole weight of the re-casting device, and the fixing component is used for fixing the quartz umbrella; the monitoring component is arranged on the lower end face of the supporting component; the fixing components are arranged at two ends of the re-throwing cylinder and are connected with the supporting component through the molybdenum rods. The invention also provides a re-feeding method for pulling the Czochralski single crystal. The invention is particularly suitable for the continuous production and re-feeding operation of a plurality of single crystals in a single furnace in single crystal pulling, solves the problems that in the prior art, silicon spraying or material ejection is easy to occur when the re-feeding barrel is manually operated to feed, the re-feeding operation is safe and easy to monitor, the re-feeding quality is good and the consistency is good, and the production efficiency is improved.

Description

Czochralski single crystal re-feeding device and re-feeding method thereof

Technical Field

The invention belongs to the technical field of solar monocrystalline silicon drawing, and particularly relates to a Czochralski monocrystalline re-feeding device and a re-feeding method thereof.

Background

In the existing single crystal pulling process, in order to reduce the production cost and improve the utilization rate of the quartz crucible to the maximum extent, a mode of repeatedly feeding silicon materials is adopted to pull multiple single crystals in a single furnace. In the re-feeding process, the process from hanging the re-feeding barrel filled with the silicon material into the single crystal furnace to taking out the re-feeding barrel from the single crystal furnace is mainly manual intervention operation, the re-feeding can be completed within about 1.5h, in the process, an operator needs to observe beside the single crystal furnace and perform manual operation all the time, time and labor are consumed, and if the crucible position is not adjusted in time or the crucible position is not adjusted reasonably, the problem of silicon spraying or material ejection is easily caused. Meanwhile, due to different skills of operators, the re-feeding time is not uniform, and the operation of pulling the single crystal in the re-feeding process is inconsistent, so that the quality difference of the produced single crystal is large, and once the batch problem occurs, the tracing cannot be carried out, and the production progress and the product quality are seriously influenced.

Disclosure of Invention

The invention provides a Czochralski single crystal re-feeding device and a re-feeding method thereof, which are particularly suitable for the continuous production and re-feeding operation of a plurality of single crystals in a single furnace in single crystal pulling, and solve the technical problems that in the prior art, the re-feeding time is long, the production efficiency is low, the product quality is unqualified and the difference is large because a re-feeding barrel is manually operated to feed materials, and silicon spraying or material ejection is easy to occur.

In order to solve the technical problems, the invention adopts the technical scheme that:

a czochralski single crystal re-casting device comprises a cylinder body, a quartz umbrella and a molybdenum rod, and also comprises a supporting component for supporting the cylinder body, a monitoring component for detecting the whole weight of the re-casting device and a fixing component for fixing the quartz umbrella, wherein the supporting component is arranged outside the cylinder body and arranged along the length direction of the cylinder body; the monitoring component is arranged on the lower end face of the supporting component; the fixing components are arranged at two ends of the re-throwing cylinder and are connected with the supporting component through the molybdenum rods.

Furthermore, the supporting component comprises an upper supporting plate and a lower supporting plate which are arranged in an aligned mode, and a plurality of supporting columns arranged between the upper supporting plate and the lower supporting plate, wherein the upper supporting plate and the lower supporting plate are matched with the inner wall of the cylinder body; the upper support plate and the upper end face of the barrel body are arranged in parallel and level.

Further, the pillars are symmetrically arranged along the periphery of the barrel body, and the height of the pillars is greater than half of the height of the barrel body and less than 2/3 of the height of the barrel body.

Furthermore, the monitoring assembly comprises a mounting plate and a monitoring piece, the mounting plate is arranged below the lower support plate, a plurality of grooves with downward openings are formed in the lower end face of the mounting plate, and the monitoring piece is fixedly arranged in the grooves.

Furthermore, the number of the grooves is two, and the grooves are symmetrically arranged on the diameter of the mounting plate; the upper support plate, the lower support plate and the mounting plate are arranged in an equal diameter mode.

Furthermore, the fixing component comprises an upper fixing disc and a lower fixing disc, and the upper fixing disc is arranged on the upper end face of the upper supporting plate and is penetrated by the molybdenum rod; the lower fixed disk is arranged on the lower end face of the quartz umbrella, and the quartz umbrella is arranged on the inner side of the lower fixed disk.

Furthermore, an arc-shaped flange is arranged on the outer circle of the lower fixing disc along the height direction of the cylinder body, and the flange is arranged towards one side of the supporting component; the inner diameter of the flange is larger than the outer diameter of the cylinder body, and the height of the flange is 10-50 mm.

A re-feeding method for pulling the Czochralski single crystal is characterized in that the re-feeding device loaded with the silicon material is adopted to be fixed in a single crystal furnace, and the lower end surface of the monitoring component is contacted with the upper end surface of a furnace cover brighness cavity of the single crystal furnace.

Further, the monitoring part monitors the weight of the silicon material in the re-feeding device in real time, and enables the re-feeding device to quantitatively feed the silicon material for multiple times, and the time is suspended for 1-2min after the silicon material is fed every time.

Furthermore, the weight of the silicon material put in each time is 10-15 kg.

Compared with the prior art, by adopting the technical scheme, the re-feeding device and the re-feeding method provided by the invention can be used for regularly and quantitatively feeding silicon materials at intervals, automatically adjusting the descending height of the quartz crucible according to the weight of each feeding amount, ensuring the safe distance between a solid-liquid interface in the quartz crucible and the lower end of the guide cylinder, preventing the silicon spraying phenomenon, keeping the consistency and the uniformity of the feeding, laying a foundation for the subsequent single crystal drawing, ensuring the stability of the re-feeding process, and simultaneously having the advantages of simple structure, easiness in operation, high safety, strong universality and the like.

Drawings

Fig. 1 is a schematic structural diagram of a double-throw device according to an embodiment of the invention;

FIG. 2 is a schematic view of a single crystal furnace and a multiple feeding apparatus according to an embodiment of the present invention;

FIG. 3 is a top view of a support assembly according to a first embodiment of the present invention;

FIG. 4 is a top view of a support assembly according to a second embodiment of the present invention;

FIG. 5 is a top view of a support assembly according to a third embodiment of the present invention;

FIG. 6 is a schematic view of the monitoring assembly in cooperation with a single crystal furnace in accordance with one embodiment of the present invention;

FIG. 7 is a top view of an upper mounting plate according to one embodiment of the present invention;

FIG. 8 is a front view of a lower mounting plate of an embodiment of the present invention;

FIG. 9 is a top view of a lower retaining plate according to one embodiment of the present invention.

In the figure:

10. barrel body 20, quartz umbrella 30 and molybdenum rod

40. Support component 41, upper supporting plate 42 and lower supporting plate

43. Pillar 50, monitoring module 51, mounting plate

52. Monitoring part 53, groove 60 and fixing component

61. Upper fixed disk 62, lower fixed disk 63, cross frame

64. Stopper 65, flange 70, single crystal furnace

71. Main chamber 72, bobble chamber 73, sub-chamber

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments.

The embodiment provides a czochralski single crystal re-casting device, as shown in fig. 1, comprising a cylinder body 10 for containing silicon materials, a quartz umbrella 20 which is arranged on the lower end surface of the cylinder body 10 and is detachably connected with the cylinder body 10 and is used for separating silicon materials, and a molybdenum rod 30 which is connected with the quartz umbrella 20 and is arranged through the cylinder body 10, further comprising a supporting component 40 for supporting the cylinder body 10, a monitoring component 50 for detecting the whole weight of the re-casting device, and a fixing component 60 for fixing the quartz umbrella 20, wherein the supporting component 40 is fixedly arranged on the outer side of the cylinder body 10 and is arranged along the length direction of the cylinder body 10; the monitoring assembly 50 is disposed at the lower end surface of the support assembly 40; the fixing members 60 are disposed at both ends of the multiple shooting pot 10 and connected to the supporting member 40 through the molybdenum rods 30. When the silicon material is fed again, the re-feeding device is arranged in the single crystal furnace 70, as shown in fig. 2, the lower end surface of the monitoring component 50 is in contact with a brix cavity 72 at the upper end port of the furnace cover of the main furnace 71, so that the supporting component 40 drives the cylinder body 10 filled with the silicon material to be arranged on the main furnace 71 in a suspended manner, when the silicon material is fed, the monitoring component 50 judges the weight of the fed silicon material through the gravity pressed on the main furnace 71 by the re-feeding device in real time, so that data is transmitted to the single crystal furnace controller, and the controller controls the fixing component 60 through the molybdenum rod 30 to control the feeding amount and time of the silicon material, so that the re-feeding of the silicon material is completed.

Specifically, the supporting assembly 40 includes an upper supporting plate 41 and a lower supporting plate 42 which are arranged in an aligned manner, and a plurality of pillars 43 which are arranged between the upper supporting plate 41 and the lower supporting plate 42, the middle of the upper supporting plate 41 and the lower supporting plate 42 is penetrated through by the cylinder body 10, and the inner walls of the upper supporting plate 41 and the lower supporting plate 42 are matched with and fixedly connected with the outer wall of the cylinder body 10; and the upper supporting plate 41 is arranged in parallel and level with the upper end surface of the cylinder body 10, so that the inlet for putting silicon materials from the upper end surface of the cylinder body 10 is ensured to be a horizontal and straight surface, and the silicon materials are conveniently put in.

Further, the structure of the upper supporting plate 41 is the same as that of the lower supporting plate 42, and preferably, the areas of the upper supporting plate 41 and the lower supporting plate 42 are the same, so that the processing is convenient and the installation and positioning are easy. The pillars 43 are at least two and uniformly arranged between the upper support plate 41 and the lower support plate 42 to ensure the stability of the fixing of the upper support plate 41 and the lower support plate 42, and the maximum outer diameters of the upper support plate 41 and the lower support plate 42 are both smaller than the inner diameter of the sub-chamber 73 of the single crystal furnace 70 and larger than the inner diameter of the furnace cover upper port chamber 72 of the main furnace 71 of the single crystal furnace 70, regardless of the structures of the upper support plate 41 and the lower support plate 42 and the shape structure of the upper support plate 41 and the lower support plate 42 matched with the pillars 43.

In this embodiment, the upper supporting plate 41 can be a circular structure, the structure of the corresponding underground supporting plate 41 is also a circular structure, the number of the pillars 43 can be two, three or four, but the pillars 43 must be uniformly wound around the outer wall of the barrel body 10 and fixed on the circumferences of the upper supporting plate 41 and the lower supporting plate 42, in this embodiment, the number of the pillars 43 is four, and all the pillars 41 are arranged on the inner side of the outer circle of the upper supporting plate 41, as shown in fig. 3, the outer diameter of the upper supporting plate 41 is smaller than the inner diameter of the auxiliary chamber 73 and larger than the inner diameter of the furnace cover upper port chamber 72 in the main furnace 71, so as to ensure that the whole re-casting device is stably fixed in the single crystal furnace 70. When the upper support plate 41 and the lower support plate 42 are both circular structures, but the pillars 43 are fixedly connected around the outer circle of the upper support plate 41 and the pillars 43 are uniformly located on the same circumference, as shown in fig. 4, at this time, the number of the pillars 43 may be two, or three or four, and in this embodiment, the number of the pillars 43 is selected to be three, so that the outer diameter of the circle where the pillars 43 are located is smaller than the inner diameter of the auxiliary chamber 73 and larger than the inner diameter of the furnace cover upper port chamber 72 in the main furnace 71. Of course, the upper supporting plate 41 and the lower supporting plate 42 may be both of a square structure, and the length of the diagonal side of the upper supporting plate 41 is smaller than the inner diameter of the sub-chamber 73 and larger than the inner diameter of the erection chamber 72, as shown in fig. 5, in this embodiment, the number of the supporting columns 43 is four, and the supporting columns are distributed on the four corners of the upper supporting plate 41, which not only can improve the supporting strength of the supporting component 40 to the barrel body 10, but also can more stably maintain the overall stability of the double throw apparatus.

Preferably, the height of the support column 43 is greater than half of the height of the cylinder body 10 and less than 2/3 of the height of the cylinder body 10, because if the height of the support column 43 is less than half of the height of the cylinder body 10, the length of the cylinder body 10 placed below the main furnace 71 is increased too long, and the lower end surface of the cylinder body 10 is further inserted into the silicon melt, so that the feeding into the quartz crucible is not performed, and the support column 43 arranged too short increases the instability of the overall placement of the multiple feeding device, and the shaking phenomenon may occur in both transportation and loading into the empty cylinder body 10. If the height of the supporting column 43 is greater than 2/3 of the height of the cylinder body 10, the distance between the lower end surface of the supporting column 43 and the lower end surface of the cylinder body 10 can be reduced, so that the length of the cylinder body 10 suspended in the main furnace 71 is short, the distance between the lower end surface of the cylinder body 10 and a solid-liquid interface in a quartz crucible is long, the distance of silicon material falling into molten silicon can be increased, the falling speed of the silicon material entering the molten silicon is increased gradually due to the gravity of the silicon material, the molten silicon can splash when the silicon material enters the silicon liquid, other impurities which are not beneficial to growth of monocrystalline silicon can be bonded by the splashed molten silicon, the single crystal drawing quality can be seriously affected, and the crystallization rate can be affected. Therefore, preferably, the height of the pillar 43 is greater than half of the height of the cylinder body 10 and less than 2/3 of the height of the cylinder body 10, which not only ensures the stability of the supporting component 40 to the vertical placement of the cylinder body 10, but also ensures that the distance between the lower end surface of the cylinder body 10 suspended in the main furnace 71 and the solid-liquid interface in the quartz crucible is within a reasonable range, and ensures that no silicon splashing occurs when the material is thrown into the quartz crucible.

The arrangement of the supporting component 40 is convenient for charging silicon materials into the empty barrel body 10, namely, the arranged lower supporting plate 42 can be clamped and fixed on the charging trolley to integrally fix the re-feeding device, so that an operator can conveniently charge materials into the barrel body 10, and the re-feeding device is stable and easy to control; when charging the silicon material into the quartz crucible, the supporting member 40 is disposed to be engaged with the erection chamber 72 of the upper end of the furnace cover of the main furnace 71, that is, the lower support plate 41 is in contact with the erection chamber 72, so that the main body 10 is erected on the main furnace 71, thereby stably operating the re-charging device for charging the silicon material.

As shown in fig. 6, the monitoring assembly 50 includes a mounting plate 51 and a monitoring member 52, the mounting plate 51 is matched with the shape structure of the lower support plate 42 and is fixedly disposed below the lower support plate 42, a plurality of grooves 53 with openings facing downward are disposed on the lower end surface of the mounting plate 51, in this embodiment, the monitoring member 52 is a pressure sensor and is embedded and fixedly disposed in the groove 53, the gravity sensor adopts a spoke type elastomer structure, i.e., a CFBHL spoke load sensor commonly used in the market, the weight of the pressed re-feeding device can be directly measured, the weight of the silicon material fed each time can be obtained according to the weight difference after each time of feeding, and how the monitoring member 52 is fixed with the groove 53 is a conventional technology, which is omitted here. Preferably, the number of grooves 53 is two, symmetrically arranged on the largest diameter of the mounting plate 51. In this embodiment, the mounting plate 51 and the lower support plate 42 are both circular structures, the mounting plate 51, the upper support plate 41 and the lower support plate 42 are all arranged in an equal diameter manner, and the groove 53 may be arranged right below the pillar 43 or may be arranged in a staggered manner, as long as the monitoring part 52 is ensured to be safely fixed in the groove 53 on the lower end surface of the mounting plate 51.

The monitoring component 50 can monitor the whole weight of the re-feeding device in real time, and transmits weight data to the controller, the controller can control the re-feeding progress in time according to the quantity of the silicon materials fed each time, and controls the fixing component 60 through the molybdenum rod 30 to adjust the position of the quartz umbrella 20 according to the feeding time set in advance, so that the silicon materials are fed into the quartz crucible.

Further, the fixing assembly 60 comprises an upper fixing disk 61 and a lower fixing disk 62, the upper fixing disk 61 is arranged on the upper end face of the upper support plate 41 and is penetrated by the molybdenum rod 30, the structure of the upper fixing disk 61 is matched with that of the upper support plate 41, and the upper fixing disk 61 is detachably connected with the upper support plate 41. In this embodiment, the upper fixed disk 61 has a circular structure, as shown in fig. 7, the outer diameter of the upper fixed disk is the same as the outer diameter of the upper support plate 41, a cross frame 63 is disposed in the middle, the cross frame 63 is located on the central diameter of the upper support plate 41 and is penetrated by the molybdenum rod 30 at the central point of the cross frame 63, a stopper 64 is disposed on the side of the cross frame 63 away from the cylinder body 10, and the stopper 64 is connected to the molybdenum rod 30 to prevent the molybdenum rod 30 from falling off the upper fixed disk 61 together with the quartz umbrella 20.

The lower fixed disk 62 is arranged on the lower end surface of the quartz umbrella 20, the quartz umbrella 20 is arranged on the inner side of the lower fixed disk 62, the lower end of the molybdenum rod 30 is fixed on the upper end surface of the lower fixed disk 60, and the upper end of the molybdenum rod 30 sequentially penetrates through the center of the quartz umbrella 20, the cylinder body 10, the cross frame 63 in the upper fixed disk 61 and the stop block 64 and is connected with the lifting rope in the auxiliary chamber 73 of the single crystal furnace 70. The lower fixing disk 62 is configured, as shown in fig. 8 to 9, such that an arc-shaped flange 65 is disposed on an outer circumference of the lower fixing disk 62 along a height direction of the cylinder body 10, the flanges 65 are symmetrically disposed with respect to a diameter of the lower fixing disk 62 and are disposed toward one side of the support assembly 40, an inner diameter of the flange 65 is larger than an outer diameter of the cylinder body 10 and larger than a maximum outer diameter of the quartz umbrella 20, and a height of the flange 65 is 10 to 50 mm. The quartz umbrella 20 can be further fixed in the setting of lower fixed disk 62, guarantees the stability of quartz umbrella 20, and quartz umbrella 20 receives the gravity impact unstability of silicon material whereabouts to move when throwing the silicon material again, and the setting of flange 65 not only can block quartz umbrella 20 to remove, still can further guarantee simultaneously that the terminal surface silicon material can not appear leaking under section of thick bamboo body 10, avoids the silicon material to be polluted or extravagant.

When the silicon material is filled in the empty re-feeding device, the upper fixing disc 61 can be detached, the supporting component 40 is matched with the charging trolley to ensure that the re-feeding device is stably and fixedly placed, the lower fixing disc 62 drives the quartz umbrella 20 to be closed with the lower end surface of the cylinder body 10, so that the cylinder body 10 forms a closed cavity with an upper end opening, then the material is directly charged from the upper end surface of the cylinder body 10, and the granular polysilicon material with the grain diameter of 50-70 mu m is filled in the cylinder body 10 until the cylinder body is full; the upper fixed disk 61 is then mounted on the upper support plate 41 and the molybdenum rod 30 is connected to the stop 64 through the cross frame 63. And finishing the work of silicon material loading of the re-feeding device.

When the re-feeding to the quartz crucible is performed, as shown in fig. 2, the sub-chamber 73 is automatically unscrewed, the re-feeding device carrying the silicon material is manually hung on a lifting rope in the sub-chamber 73 through the upper end of the molybdenum rod 30, and the re-feeding device is entirely transferred into the sub-chamber 73 through the lifting rope. The air in the sub-chamber 73 is automatically purified, after the purification is finished, a flap valve (omitted in the figure) connecting the sub-chamber 73 and the main chamber 71 is automatically unscrewed, the lowering of the re-injection device is adjusted and adjusted through a lifting rope, and the mounting plate 51 in the monitoring assembly 50 is in contact with the ball cavity 72 in the main chamber 71, so that the re-injection device is integrally and stably suspended in the main chamber 71; simultaneously, the pressure and the flow of argon in the single crystal furnace 70 are adjusted, the re-feeding device is started after the adjustment is finished, the gravity sensor of the monitoring piece 52 starts to work, the gravity sensor records the total weight of the initial re-feeding device, the re-feeding is carried out quantitatively at a certain time interval according to the preset process interval, namely, the lifting rope moves downwards, the molybdenum rod 30 drives the lower fixed disc 62 and the quartz umbrella 20 to move downwards together, the silicon material in the cylinder body 10 slowly moves towards the quartz crucible along the slope surface of the quartz umbrella 20, the weight of the re-feeding device is recorded in real time by the gravity sensor and compared with the weight of the initial re-feeding device, when the difference value between the weight of the re-feeding device and the weight of the initial re-feeding device is the preset weight of the re-feeding silicon material, the gravity sensor transmits a signal to the system controller, and the controller controls the lifting rope to drive the quartz umbrella 20 and the lower fixed disc 62 to move upwards through the molybdenum rod 30, so that the quartz umbrella 20 and the lower end surface of the cylinder body 10 are closed, and the feeding is suspended; and the controller controls the pause time, and after the pause is finished, the steps are repeated, and the silicon material is continuously put into the quartz crucible until the silicon material is completely put again. Then the re-throwing device is lifted by a lifting rope to move from the main chamber 71 to the auxiliary chamber 73, and a flap valve connecting the auxiliary chamber 73 and the main chamber 71 is closed; then the sub-chamber 73 is unscrewed, and the empty re-casting device is moved out of the sub-chamber 73, so that the re-casting process is completed.

The re-throwing device provided by the invention has the advantages that the structure is simple, the design is reasonable, the barrel body 10 can be more stably fixed through the supporting assembly 40, meanwhile, the safety of the barrel body 10 in moving and transportation can be ensured, the integral strength of the re-throwing device is further improved, and the stable placement of the re-throwing device is more facilitated; the monitoring component 50 can further effectively monitor the weight of silicon material thrown into the quartz crucible, improve the automatic control of the re-throwing device, and avoid the interference operation of personnel, thereby not only ensuring the re-throwing quality and the re-throwing accuracy, but also solving the technical problems of silicon spraying or material ejection and the like which are easy to occur, effectively reducing the re-throwing time, improving the production efficiency, further improving the crystal forming rate of single crystal pulling and ensuring the consistency of the product quality.

A re-feeding method for pulling a single crystal in a Czochralski manner adopts the re-feeding device, and comprises the following steps:

s1: and loading the silicon material into the empty re-feeding device.

Specifically, the upper fixing disk 61 is removed, the support assembly 40 is matched with the charging trolley, the re-feeding device is stably and fixedly placed, the lower fixing disk 62 drives the quartz umbrella 20 to be closed with the lower end face of the cylinder body 10, the cylinder body 10 forms a closed cavity with an opening at the upper end, then charging is directly carried out from the upper end face of the cylinder body 10, and granular polysilicon silicon materials with the grain diameter of 50-70 microns are charged into the cylinder body 10 until the cylinder body is full; the upper fixed disk 61 is then mounted on the upper support plate 41 and the molybdenum rod 30 is connected to the stop 64 through the cross frame 63. And at this point, the work of filling the empty re-feeding device with the silicon material is completed.

S2: the re-feeding device loaded with the silicon material is fixed in the single crystal furnace 70, and the lower end surface of the monitoring assembly 50 is contacted with the upper end surface of a furnace cover brighs cavity 72 in a main furnace 71 of the single crystal furnace 70.

Specifically, the auxiliary chamber 73 is automatically unscrewed, the re-feeding device loaded with the silicon material is manually hung and buckled on a lifting rope in the auxiliary chamber 73 through the upper end of the molybdenum rod 30, and the re-feeding device is integrally transferred into the auxiliary chamber 73 through the lifting rope. Automatically purifying the air in the auxiliary chamber 73, automatically unscrewing a flap valve connecting the auxiliary chamber 73 and the main chamber 71 after purification is finished, adjusting the descending of the re-throwing device through a lifting rope, and enabling the mounting plate 51 in the monitoring assembly 50 to be in contact with the erection cavity 72 in the main chamber 71 so as to enable the re-throwing device to be integrally and stably suspended in the main chamber 71; meanwhile, the pressure and flow of argon in the single crystal furnace 70 are adjusted, and the re-feeding device is started after the adjustment is finished.

S3: and starting the re-feeding device, monitoring the weight of the silicon material in the re-feeding device in real time through the monitoring part 52 according to the set process, quantitatively feeding the silicon material for multiple times, pausing for 1-2min after feeding the silicon material every time, and feeding the silicon material 10-15kg every time.

Specifically, the gravity sensor of the monitoring part 52 starts to work, records the initial total weight of the re-feeding device, and quantitatively re-feeds the silicon material according to a preset process interval at a certain time, namely, the weight of the silicon material fed each time is set to be 10-15kg, and the silicon material fed each time is suspended for 1-2 min. The lifting rope in the auxiliary chamber 73 moves downwards, and then the molybdenum rod 30 drives the lower fixed disc 62 and the quartz umbrella 20 to move downwards together, so that a gap is formed between the lower end surface of the cylinder body 10 and the quartz umbrella 20, and further, the silicon material in the cylinder body 10 moves slowly into the quartz crucible along the slope surface of the quartz umbrella 20; the weight sensor of the monitoring control part 52 records the weight of the re-feeding device in real time and compares the weight with the initial weight of the re-feeding device, when the difference value between the weight of the re-feeding device and the initial weight of the re-feeding device is the preset weight of the re-feeding silicon material of 10-15kg, the gravity sensor transmits a signal to the system controller, and the controller controls the lifting rope to drive the quartz umbrella 20 and the lower fixed disk 62 to move upwards through the molybdenum rod 30, so that the lower end surfaces of the quartz umbrella 20 and the cylinder body 10 are closed, and the feeding is suspended.

When the silicon material is put in, the solid-liquid interface of the quartz crucible is correspondingly raised because the silicon material in the quartz crucible is continuously increased, and in order to ensure the safe distance between the lower end surface of the guide cylinder and the solid-liquid interface, the position height of the quartz crucible needs to be adjusted while the silicon material is repeatedly put in order to adapt to the increase of the repeatedly-added silicon material which is gradually increased. The method is characterized in that every 1kg of silicon material is put in, when the gravity sensor monitors that 1kg of silicon material is put in, a signal is transmitted to the controller, the controller controls the quartz crucible to descend, so that the position of a solid-liquid cross section in the quartz crucible descends by 0.8-1mm, the crucible position value of the quartz crucible is guaranteed to be a fixed value, the problem that silicon overflows or sprays due to the fact that the crucible position of the quartz crucible does not descend timely along with the increase of the material is solved, and meanwhile, the problem that the silicon material is accumulated in the quartz crucible and the material is ejected can be solved. If the gravity sensor of the monitoring control part 52 monitors that the silicon material which is repeatedly thrown each time is more than 10-15kg, the alarm is started, and the silicon spraying or the material ejection can be avoided.

And after the controller controls the re-feeding device to pause for 1-2min, ending the pause, repeating the steps, and continuously feeding the silicon material into the quartz crucible until the re-feeding of the silicon material is finished.

S4: and withdrawing the re-throwing device and taking out the re-throwing device.

Specifically, the re-throwing device is lifted by a lifting rope to move from the main chamber 71 to the auxiliary chamber 73, and a flap valve connecting the auxiliary chamber 73 and the main chamber 71 is closed; then the sub-chamber 73 is unscrewed, and the empty re-casting device is moved out of the sub-chamber 73, so that the re-casting process is completed.

The re-feeding method provided by the invention can be used for regularly and quantitatively feeding silicon materials at intervals, automatically adjusting the descending height of the quartz crucible according to the weight of each feeding amount, ensuring the safety distance between a solid-liquid interface in the quartz crucible and the lower end of the guide cylinder, preventing the silicon spraying phenomenon, keeping the consistency and uniformity of the feeding, laying a foundation for the subsequent single crystal pulling, ensuring the stability of the re-feeding process, and simultaneously has the advantages of simple structure, easiness in operation, high safety, strong universality and the like.

The embodiments of the present invention have been described in detail, and the description is only for the preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made within the scope of the present invention shall fall within the scope of the present invention.

Claims

1. A czochralski single crystal re-casting device comprises a cylinder body, a quartz umbrella and a molybdenum rod, and is characterized by also comprising a supporting component for supporting the cylinder body, a monitoring component for detecting the whole weight of the re-casting device and a fixing component for fixing the quartz umbrella, wherein the supporting component is arranged outside the cylinder body and arranged along the length direction of the cylinder body; the monitoring component is arranged on the lower end face of the supporting component; the fixing components are arranged at two ends of the re-throwing cylinder and are connected with the supporting component through the molybdenum rods.

2. The apparatus according to claim 1, wherein the support assembly comprises an upper support plate and a lower support plate which are arranged in an aligned manner, and a plurality of support columns which are arranged between the upper support plate and the lower support plate, wherein the upper support plate and the lower support plate are matched with the inner wall of the barrel body; the upper support plate and the upper end face of the barrel body are arranged in parallel and level.

3. A Czochralski single crystal re-casting apparatus as claimed in claim 2, wherein the pillars are symmetrically disposed along the circumference of the barrel body, and the height of the pillars is greater than half of the height of the barrel body and less than 2/3 of the height of the barrel body.

4. The Czochralski single crystal re-throwing apparatus according to claim 2 or 3, wherein the monitoring assembly comprises a mounting plate and a monitoring member, the mounting plate is arranged below the lower support plate, a plurality of grooves with downward openings are arranged on the lower end surface of the mounting plate, and the monitoring member is fixedly arranged in the grooves.

5. The apparatus according to claim 4, wherein the number of the grooves is two and the grooves are symmetrically arranged on the diameter of the mounting plate; the upper support plate, the lower support plate and the mounting plate are arranged in an equal diameter mode.

6. The Czochralski single crystal re-throwing apparatus according to any one of claims 2 to 3 and 5, wherein the fixing assembly comprises an upper fixing disk and a lower fixing disk, the upper fixing disk is arranged on the upper end surface of the upper supporting plate and is penetrated by the molybdenum rod; the lower fixed disk is arranged on the lower end face of the quartz umbrella, and the quartz umbrella is arranged on the inner side of the lower fixed disk.

7. The Czochralski single crystal re-casting device as set forth in claim 6, wherein an arc-shaped flange is provided at an outer circumference of the lower fixed disk in a height direction of the barrel body, the flange being provided toward the support member; the inner diameter of the flange is larger than the outer diameter of the cylinder body, and the height of the flange is 10-50 mm.

8. A re-feeding method for pulling a Czochralski single crystal, characterized in that the re-feeding device loaded with a silicon material is fixed in a single crystal furnace by using the re-feeding device as set forth in any one of claims 1 to 7, and the lower end face of the monitoring member is brought into contact with the upper end face of a furnace cover brix chamber of the single crystal furnace.

9. The re-feeding method for pulling the Czochralski single crystal as recited in claim 8, wherein the monitoring and controlling part monitors the weight of the silicon material in the re-feeding device in real time, and enables the re-feeding device to quantitatively feed the silicon material for a plurality of times, and the time is suspended for 1-2min after each silicon material feeding.

10. The method of claim 9, wherein the weight of the silicon material charged per time is 10 to 15 kg.