Czochralski round silicon core growth furnace

Abstract

A Czochralski round silicon core growth furnace, comprising a furnace body, a pulling and rotating device, a multi-axis pulling disc device and a heat shield lifting device, wherein the furnace body comprises a main furnace chamber and an auxiliary furnace chamber, and the auxiliary furnace chamber is detachably connected to the main furnace chamber; the pulling and rotating device comprises a crystal pulling and lifting mechanism and a rotating mechanism; the multi-axis pulling disc device comprises a housing and a gear transmission mechanism located in the housing; the crystal pulling and lifting mechanism is connected to the housing; the rotating mechanism is connected to the gear transmission mechanism; the gear transmission mechanism is connected to a plurality of sets of seed crystals; and the heat shield lifting device comprises a lifting drive device and a perforated water-cooled jacket connected to the lifting drive device. The perforated water-cooled jacket is lifted by means of the lifting device to move up and down, and the auxiliary furnace chamber is detachably connected to the main furnace chamber, such that the function of cleaning ash without furnace shutdown is achieved, thereby effectively preventing impurities from falling, and ensuring the purity of a silicon melt.

Description

A Czochralski-type circular silicon core growth furnace Technical Field

[0001] This invention belongs to the field of silicon core preparation and relates to a Czochralski-type circular silicon core growth furnace. Background Technology

[0002] Most existing silicon cores are produced through zone melting, primarily using high-frequency coils and seed chucks to complete the pulling process. However, this method limits the number of silicon cores that can be pulled per batch, and the pulses generated by the stepper motors and AC motors used during the pulling process can affect the silicon core pulling process, resulting in low pulling efficiency. Furthermore, existing cooling pads also have the following drawbacks: Firstly, most cooling pads adopt an integral design and a single-hole structure with a live joint assembly for sealing. The lifespan of the sealing ring is significantly affected under long-term vacuum and high-temperature conditions, and there is a risk of water leakage at the sealing joint. The single-hole cooling... Firstly, during the silicon core pulling process, the heat radiation from the molten silicon shines directly upwards through the central hole of the cooling plate, causing a high temperature rise in the overall furnace chamber and auxiliary chamber, which places high demands on the materials of the pulling device. Secondly, if the cooling plate cannot be raised above the rotary valve, the silicon material cannot be re-added during the crystal pulling process, resulting in the inability to continue crystal pulling. Thirdly, if the cooling plate cannot be raised to the auxiliary chamber end, the molten silicon and volatile impurities in the furnace will condense on its side walls or bottom surface during the crystal pulling process. When the condensation thickness reaches a certain level, there is a risk of it falling off, affecting the purity of the molten silicon, and also posing a risk of crystal jamming during crystal pulling.

[0003] Summary of the Invention

[0004] In order to overcome at least one deficiency of the prior art, the present invention provides a Czochralski-type circular silicon core growth furnace.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a direct-pull circular silicon core growth furnace, comprising a furnace body, a lifting and rotating device, a multi-axis lifting plate device, and a heat shield lifting device. The furnace body includes a main furnace chamber and an auxiliary furnace chamber, which are detachably connected to the main furnace chamber. The lifting and rotating device includes a crystal lifting mechanism and a rotating mechanism. The multi-axis lifting plate device includes a housing and a gear transmission mechanism located inside the housing. The crystal lifting mechanism is connected to the housing, and the rotating mechanism is connected to the gear transmission mechanism. The gear transmission mechanism connects multiple sets of seed crystals. The heat shield lifting device includes a lifting drive device and a porous water-cooling jacket connected to the lifting drive device.

[0006] Furthermore, the main furnace chamber is connected to a rotary vane valve, which is located between the auxiliary furnace chamber and the main furnace chamber. The opening and closing of the rotary vane valve controls the connection between the main furnace chamber and the auxiliary furnace chamber. A heating device is installed in the main furnace chamber, which includes a quartz crucible and a graphite support rod connected to the quartz crucible. The graphite support rod is slidably connected to the main furnace chamber.

[0007] Furthermore, the crystal pulling mechanism includes a lifting mechanism and a tungsten wire rope connected to the lifting mechanism. One end of the tungsten wire rope is wound around a lifting winding shaft, and the other end is connected to the housing. The rotating mechanism includes a cable winding mechanism and a rotary motor. The cable winding mechanism is connected to the auxiliary furnace chamber, and the rotary motor is linked with multiple sets of seed crystals.

[0008] Furthermore, the heat shield lifting device is connected to the auxiliary furnace chamber. The heat shield lifting device includes a lifting drive device and a porous water-cooled jacket. The lifting drive device is connected to the porous water-cooled jacket and the auxiliary furnace chamber. The lifting drive device controls the porous water-cooled jacket to move up and down.

[0009] Furthermore, the porous water cooling jacket includes at least two sets of water cooling plate assemblies. Each water cooling plate assembly includes a water cooling plate and a water inlet / outlet device connected to the water cooling plate. The water cooling plate is provided with a water flow channel communicating with the water inlet / outlet device, and the water cooling plates of the two sets of water cooling plate assemblies are connected.

[0010] Furthermore, the water inlet and return device includes a water inlet structure and a water return structure, which are respectively connected to the water flow channel of the water cooling plate. The water inlet structure, the water flow channel, and the water return structure constitute the water inlet and return channel.

[0011] Furthermore, the water inlet and outlet device also includes a regulating device, which includes a temperature flow meter and an over-temperature switch. The temperature flow meter and the over-temperature switch are installed on the water outlet structure. The over-temperature switch is connected to the temperature flow meter, and the temperature flow meter detects the real-time water flow rate and temperature of the water outlet.

[0012] Furthermore, the water cooling plate includes an upper water cooling plate, a water cooling plate connecting pipe, and a lower water cooling plate, with the upper and lower water cooling plates connected by the water cooling plate connecting pipe.

[0013] Furthermore, the upper plate of the water-cooling jacket is provided with an upper water inlet chamber and an upper water return chamber, and the lower plate of the water-cooling jacket is provided with a lower water inlet chamber and a lower water return chamber. The upper water inlet chamber and the lower water inlet chamber, the lower water inlet chamber and the lower water return chamber, and the upper water return chamber and the lower water return chamber are respectively connected through water-cooling jacket connecting pipes. The upper water inlet chamber, the lower water inlet chamber, the lower water return chamber, and the upper water return chamber constitute a water flow channel.

[0014] Furthermore, the lifting drive device includes two sets, which are respectively connected to the auxiliary furnace chamber and respectively connected to two sets of water-cooled plate assemblies.

[0015] In summary, the advantages of this invention are:

[0016] 1) The cooling jacket of the present invention is a split structure consisting of two sets of water-cooling plate assemblies, which is simple to assemble. The water-cooling plate assemblies are an integrated structure, and the inlet and outlet water pipes are welded to the water-cooling plate, which effectively avoids the risk of pipe joint failure in a vacuum high-temperature environment and ensures the reliability of the cooling jacket. The water-cooling plates of the two sets of water-cooling plate assemblies have separate inlet and outlet water structures, which reduces the cooling path and effectively improves the cooling effect. The inlet and outlet water device is equipped with a temperature and flow meter and an over-temperature switch. The temperature and flow meter and the over-temperature switch realize the function of real-time monitoring of water temperature and flow rate during crystal pulling. When the water temperature detected by the temperature and flow meter exceeds the set value, the over-temperature switch threshold alarm is triggered, and the water flow rate is adjusted by manual or automatic intervention. The over-temperature switch effectively realizes the over-temperature pre-tightening function, further improving the cooling effect.

[0017] 2) When the silicon material needs to be refilled, the lifting device drives the porous water cooling jacket to move upward, and the material cylinder connected to the porous water cooling jacket moves upward synchronously with the porous water cooling jacket. The porous water cooling jacket and the material cylinder are moved to the auxiliary furnace chamber for refilling. The rotary valve is closed to seal the main furnace chamber, thereby realizing the function of refilling silicon material without stopping the furnace during the drawing process by switching between the open and closed states of the rotary valve.

[0018] 3) This invention uses a lifting device to move the porous water-cooled jacket up and down, and a structure that allows the auxiliary furnace chamber and the main furnace chamber to be detachably connected, to achieve the function of cleaning ash without stopping the furnace, effectively preventing impurities from falling and ensuring the purity of the silicon liquid.

[0019] 4) This invention uses a rotating device as a power source and achieves an ideal number of output shafts through the structural design of the multi-shaft gearbox, which greatly improves production efficiency and significantly enhances the production efficiency and quality of silicon cores. The multi-shaft gearbox has a simple manufacturing process and is suitable for large-scale modern production. Attached Figure Description

[0020] Figure 1 is a schematic diagram of the crystal pulling position in the circular silicon core growth furnace of the present invention.

[0021] Figure 2 is a schematic diagram of the position of the circular silicon core growth furnace before feeding according to the present invention.

[0022] Figure 3 is a schematic diagram of the feeding position of the circular silicon core growth furnace of the present invention.

[0023] Figure 4 is a schematic diagram of the internal structure of the multi-axis lifting disc device of the present invention.

[0024] Figure 5 is a schematic diagram of the distribution of the lifting shaft of the present invention.

[0025] Figure 6 is a schematic diagram of the porous water-cooling jacket of the present invention.

[0026] Figure 7 is a top view of the porous water-cooled jacket of the present invention.

[0027] Figure 8 is a front view of the porous water-cooled jacket of the present invention.

[0028] Figure 9 is a cross-sectional view of AA in Figure 7 of the present invention.

[0029] Figure 10 is a cross-sectional view of BB in Figure 8 of the present invention.

[0030] Figure 11 is a cross-sectional view of CC in Figure 8 of the present invention.

[0031] The diagram shows: Main furnace chamber 11, auxiliary furnace chamber 12, rotary valve 14, crystal pulling mechanism 21, rotating mechanism 22, multi-axis lifting plate device 23, horizontal adjustment mechanism 24, lifting drive device 31, porous water cooling jacket 32, furnace bottom plate 111, lower furnace chamber 112, upper furnace chamber 113, furnace cover 114, quartz crucible 131, insulation system, main heater 132, side heater 133, heat guide tube 134, bottom insulation layer 135, upper insulation layer 136, lower insulation layer 137, silicon liquid 138, graphite support rod 139, tungsten wire rope 211, lifting mechanism 212, cable winding and unwinding mechanism 221, rotary motor 222, cable 223, outer ring driven wheel 230, housing 231, main drive wheel 232, outer ring main drive wheel 233, inner ring main drive wheel 234, and lifting shaft. 235. Lifting tungsten wire rope; 236. Lifting weight; 237. Drive wheel; 238. Inner ring drive wheel; 239. Lifting drive device; 31. Perforated water cooling jacket; 32. Water cooling plate assembly; 33. Water cooling plate; 34. Inlet and outlet water device; 35. Cooling hole; 340. Upper water cooling jacket plate; 341. Water cooling jacket connecting pipe; 342. Lower water cooling jacket plate; 343. Temperature measuring flow meter; 350. Inlet pipe connector; 351. Inlet pipe; 352. Outlet pipe connector; 353. Outlet pipe; 354. Over-temperature switch; 355. Upper water cooling jacket inlet chamber; 3411. Upper water cooling jacket outlet chamber; 3412. Flow chamber; 3413. First connecting pipe; 3421. Second connecting pipe; 3422. Third connecting pipe; 3423. Fourth connecting pipe; 3424. Lower water cooling jacket inlet chamber; 3431. Lower water cooling jacket outlet chamber; 3432. Screw hole; 3433. Detailed Implementation

[0032] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0033] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0034] In this embodiment of the invention, all directional indicators (such as up, down, left, right, front, back, lateral, longitudinal, etc.) are only used to explain the relative positional relationship and movement of each component in a specific posture. If the specific posture changes, the directional indicator will also change accordingly.

[0035] Due to installation errors and other reasons, the parallel relationship referred to in the embodiments of the present invention may actually be an approximate parallel relationship, and the perpendicular relationship may actually be an approximate perpendicular relationship.

[0036] Example 1:

[0037] As shown in Figures 1-11, a direct-pull circular silicon core growth furnace includes a furnace body, a lifting and rotating device, a multi-axis lifting plate device 23, and a heat shield lifting device. The furnace body includes a main furnace chamber 11 and an auxiliary furnace chamber 12, which are detachably connected to the main furnace chamber 11. The lifting and rotating device is connected to the furnace body and the multi-axis lifting plate device 23, respectively. The multi-axis lifting plate device 23 is connected to multiple sets of seed crystals. The heat shield lifting device includes a lifting drive device 31 and a porous water-cooling jacket 32 ​​connected to the lifting drive device 31.

[0038] The main furnace chamber 11 is the main working environment during crystal pulling. The main furnace chamber 11 includes a furnace bottom plate 111, a lower furnace chamber 112, an upper furnace chamber 113, and a furnace cover 114 connected in sequence. The furnace cover 114 is connected to a rotary valve 14, which is located between the auxiliary furnace chamber 12 and the main furnace chamber 11. The opening and closing of the rotary valve 14 controls the connection between the main furnace chamber 11 and the auxiliary furnace chamber 12.

[0039] A heating device is installed inside the main furnace chamber 11. This device includes a quartz crucible 131, a heat preservation system, a main heater 132, side heaters 133, and a heat conduit 134. The heat preservation system includes a lower heat preservation layer 137, an upper heat preservation layer 136, and a bottom heat preservation layer 135. The bottom heat preservation layer 135 is installed above the furnace bottom plate 111, and the main heater 132 is installed on it. The main heater 132 is used to heat the bottom of the quartz crucible 131, melting the silicon material. After the silicon material in the quartz crucible 131 melts... Silicon liquid 138 is formed; side heaters 133 are distributed in a ring around the furnace bottom plate 111 to ensure the uniformity and stability of the temperature around the crucible; the lower insulation layer 137, together with the upper insulation layer 136 and the bottom insulation layer 135, form a complete insulation system, so that the heat inside the furnace body is dissipated to the outside of the furnace as little as possible, saving energy and heat insulation; the heat guide tube 134 is installed above the upper insulation layer 136, which serves as heat insulation on the one hand and argon gas guide on the other hand, so that the airflow is uniformly convection, making the crystal pulling more uniform.

[0040] The bottom of the quartz crucible 131 is also provided with a graphite support rod 139, which is located at the center of the furnace bottom plate 111. The graphite support rod 139 can move up and down to compensate for the lack of silicon liquid and keep the liquid level of the silicon liquid stable at the same level.

[0041] The crystal lifting and rotating device includes a crystal lifting mechanism 21, a rotating mechanism 22, and a horizontal adjustment mechanism 24. A multi-axis crystal lifting disk device 23 is connected to multiple sets of seed crystals. The crystal lifting mechanism 21 and the rotating mechanism 22 are respectively connected to the multi-axis crystal lifting disk device 23. The horizontal adjustment mechanism 24 is connected to the crystal lifting mechanism 21. The multi-axis crystal lifting disk device 23 is raised and lowered by the crystal lifting mechanism 21, the multiple sets of seed crystals are rotated by the rotating mechanism 22, and the position of the crystal lifting mechanism 21 is adjusted by the horizontal adjustment mechanism 24.

[0042] The horizontal adjustment mechanism 24 is fixed above the auxiliary furnace chamber 12. The crystal pulling mechanism 21 includes a lifting mechanism 212 and a tungsten wire rope 211 connected to the lifting mechanism. The lifting mechanism is connected to the horizontal adjustment mechanism 24. The horizontal adjustment mechanism 24 drives the lifting mechanism to a horizontal position to ensure that the crystal pulling mechanism 21 is in the center position.

[0043] The lifting mechanism includes a wire winding shaft support (not shown in the figure), a lifting wire winding shaft (not shown in the figure), and a wire winding shaft rotary motor (not shown in the figure). The wire winding shaft support is fixed to the horizontal adjustment mechanism 24, the wire winding shaft rotary motor is fixed to the wire winding shaft support, the lifting wire winding shaft is located inside the wire winding shaft support, and the motor output shaft of the wire winding shaft rotary motor is connected to the lifting wire winding shaft. One end of the tungsten wire rope 211 is wound around the lifting wire winding shaft, and the other end is connected to the multi-axis lifting plate device 23. The wire winding shaft rotary motor starts and drives the lifting wire winding shaft to rotate, realizing the winding and unwinding of the tungsten wire rope 211, so that the tungsten wire rope 211 lifts the multi-axis lifting plate device 23 at the set crystal growth speed.

[0044] The rotating mechanism 22 includes a cable winding and unwinding mechanism 221 and a rotary motor 222. The cable winding and unwinding mechanism 221 is connected to the auxiliary furnace chamber 12. The rotary motor 222 is mounted on the multi-axis lifting plate device 23 and is linked with multiple seed crystals. The cable winding and unwinding mechanism 221 and the rotary motor 222 are connected by a cable 223. The multi-axis lifting plate device 23 is lifted and lowered by a tungsten wire rope 211, and the seed crystals are rotated by the rotary motor 222.

[0045] The crystal pulling mechanism 21 controls the tungsten wire rope 211 to raise and lower the multi-axis lifting plate device 23, thereby controlling the raising and lowering of the seed crystal. During the raising and lowering of the multi-axis lifting plate device 23, the cable winding and unwinding mechanism 221 is activated to control the rotary motor 222 to raise and lower synchronously through the cable 223, so that the moving speed of the rotary motor 222 and the multi-axis lifting plate device 23 are consistent, minimizing the pressure of the rotary motor 222 on the multi-axis lifting plate device 23. The rotary motor 222 provides a power source to control the rotation of the seed crystal. During crystal pulling, the seed crystal first comes into contact with the silicon liquid 138. Under the action of the crystal pulling mechanism 21 and the rotary mechanism 22, the seed crystal is raised upward and rotates at the same time, so that the diameter of the seed crystal gradually increases to form a silicon core, until the silicon core is formed.

[0046] The cable winding mechanism 221 includes a winding and unwinding spool (not shown in the figure) and a winding and unwinding spool motor (not shown in the figure). The winding and unwinding spool motor is fixedly installed in the auxiliary furnace chamber 12. The winding and unwinding spool is located inside the auxiliary furnace chamber 12. The motor output shaft of the winding and unwinding spool motor is fixedly connected to the winding and unwinding spool. One end of the cable 223 is wound on the winding and unwinding spool, and the other end is connected to the rotary motor 222. When the winding and unwinding spool motor is started, it drives the winding and unwinding spool to rotate, thereby realizing the winding and unwinding of the cable 223 and driving the rotary motor 222 to lift at a set speed.

[0047] The multi-axis lifting plate device 23 includes a housing 231 and a gear transmission mechanism. The gear transmission mechanism is located in the housing 231. The tungsten wire rope 211 and the rotary motor 222 are respectively connected to the housing 231. The power output shaft of the rotary motor 222 is connected to the gear transmission mechanism, and the rotary motor 222 serves as the power source for the gear transmission mechanism.

[0048] The gear transmission mechanism includes a main drive wheel 232, a driven wheel 238, an outer main drive wheel 233, an inner main drive wheel 234, an outer driven wheel 230, and an inner driven wheel 239. The power output shaft of the rotary motor 222 is connected to the main drive wheel 232. The main drive wheel 232 is meshed with the driven wheel 238. The driven wheel 238, the outer main drive wheel 233, and the inner main drive wheel 234 are coaxially arranged via a rotating shaft. The rotating shaft is rotatably connected to the housing 231. The outer main drive wheel 233 is meshed with the outer driven wheel 230. The inner main drive wheel 239... 34 is meshed with the inner ring drive wheel 239. The outer ring drive wheel 230 and the inner ring drive wheel 239 are fixedly provided with a lifting shaft 235. The lifting shaft 235 is fixedly provided with a lifting tungsten wire rope 236. The lifting tungsten wire rope 236 is fixedly provided with a lifting weight 237. The lifting weight 237 is fixedly provided with a seed crystal. The rotating device, as the input power of the gear transmission mechanism, transmits the rotational motion sequentially from the main drive wheel 232, the driven wheel 238, the outer ring main drive wheel 233, the inner ring main drive wheel 234, the outer ring driven wheel 230 and the inner ring driven wheel 239 to the seed crystal, causing the seed crystal to rotate.

[0049] Drive wheel 238 is coaxially arranged with outer ring main drive wheel 233 and inner ring main drive wheel 234. The rotation of drive wheel 238 drives outer ring main drive wheel 233 and inner ring main drive wheel 234 to rotate simultaneously, thereby driving outer ring driven wheel 230 and inner ring driven wheel 239 to rotate simultaneously, so that the seed crystal rotates in the same direction and at the same speed.

[0050] In this embodiment, multiple sets of outer ring drive wheels 230 and inner ring drive wheels 239 are provided, and they are distributed in inner and outer rings. The number and distribution of seed crystals can be set according to actual needs, and the number of seed crystals is set to 46.

[0051] This application achieves multi-axis crystal pulling with one-axis input and multiple-axis output by driving the outer main drive wheel 233 and the inner main drive wheel 234 to rotate from the drive wheel 238, thereby driving multiple seed crystals to rotate synchronously in the same direction and at the same speed. Compared with the existing single-axis crystal pulling, this effectively improves the production efficiency of silicon cores.

[0052] This application uses a rotating device as a power source and achieves an ideal number of output shafts through the structural design within a multi-shaft gearbox, greatly improving production efficiency and significantly enhancing the production efficiency and quality of silicon cores. The multi-shaft gearbox has a simple manufacturing process and is suitable for large-scale modern production.

[0053] The horizontal adjustment mechanism 24 can adopt a transmission structure such as motor drive or cylinder drive, but this embodiment is not limited to this.

[0054] As shown in Figures 6-11, the heat shield lifting device is connected to the auxiliary furnace chamber 12. The heat shield lifting device includes a lifting drive device 31 and a porous water-cooled jacket 32. The lifting drive device 31 is connected to the porous water-cooled jacket 32 ​​and the auxiliary furnace chamber 12. The lifting drive device 31 controls the porous water-cooled jacket 32 ​​to move up and down.

[0055] The porous water cooling jacket 32 ​​includes at least two sets of water cooling plate assemblies 33. Each water cooling plate assembly 33 includes a water cooling plate 34 and a water inlet / outlet device 35 connected to the water cooling plate. The water cooling plate 34 is provided with a water flow channel communicating with the water inlet / outlet device 35. The water cooling plates 34 of the two sets of water cooling plate assemblies 33 are connected.

[0056] The water cooling plate assembly 33 is an integrated structure. Two sets of water cooling plate assemblies 33 are connected to form a porous water cooling jacket. Compared with the existing integrated water cooling jacket, the porous water cooling jacket in this embodiment is set as a split structure composed of two sets of water cooling plate assemblies 33. The split porous water cooling jacket is easy to install and can be placed into the equipment as a whole, avoiding the risk of pipe joint failure in a vacuum high temperature environment.

[0057] Two sets of water-cooled plate components 33 are distributed around the perimeter, but the number and distribution of the water-cooled plate components 33 in this application are not limited to this.

[0058] In this embodiment, the two sets of water-cooled plate assemblies 33 have the same structure. The structure of one set of water-cooled plate assemblies 33 will be described as an example.

[0059] The water inlet and return device 35 includes an inlet structure and a return structure. The inlet structure and the return structure are respectively connected to the water flow channel of the water cooling plate 34. The inlet structure, the water flow channel, and the return structure constitute the water inlet and return channel. Water flows along the water inlet and return channel to achieve individual water inlet and return cooling of a single water cooling plate assembly 33. Compared with the existing integral water cooling jacket, which has the disadvantage of long water channel distribution leading to low cooling effect, this application assembles the water cooling plate assembly 33 in a split manner and sets an independent water inlet and return device 35 in each water cooling plate assembly 33, reducing the cooling path and effectively improving the cooling effect.

[0060] The water inlet structure includes an inlet pipe connector 351 and an inlet pipe 352. One end of the inlet pipe 352 is connected to the inlet pipe connector 351, and the other end is connected to the inlet of the water flow channel. Water flows into the water flow channel through the inlet pipe connector 351, the inlet pipe 352, and the inlet. The water return structure includes a water return pipe connector 353 and a water return pipe 354. One end of the water return pipe 354 is connected to the water return pipe connector 353, and the other end is connected to the outlet of the water flow channel. Water flows out through the outlet, the water return pipe 354, and the water return pipe connector 353.

[0061] The inlet pipe 352 and the return pipe 354 are coaxially arranged. The return pipe 354 is sleeved on the outside of the inlet pipe 352. The ends of the inlet pipe 352 and the return pipe 354 are connected to the inlet and outlet respectively. Both the inlet pipe 352 and the return pipe 354 are made of heat insulation material to prevent the return water temperature from affecting the inlet water temperature.

[0062] The inlet and outlet water device 35 also includes an adjustment device, which includes a temperature flow meter 350 and an over-temperature switch 355. The temperature flow meter 350 and the over-temperature switch 355 are installed on the return water pipe 354. The over-temperature switch 355 is connected to the temperature flow meter 350. The temperature flow meter 350 detects the real-time water flow rate and temperature of the return water, realizing the function of real-time monitoring of water temperature and flow rate during crystal pulling. When the water temperature detected by the temperature flow meter 350 exceeds the set value, the over-temperature switch 355 triggers a threshold alarm. The water flow rate is adjusted manually or automatically. The over-temperature switch 355 effectively realizes the over-temperature pre-tightening function, further improving the cooling effect.

[0063] In this embodiment, the inlet pipe 352 and the return pipe 354 are welded to the water cooling plate 34. Compared with the existing method of assembling and sealing with a union, the life of the sealing ring is affected by high temperature and failure occurs, resulting in water leakage. This application eliminates the union assembly and sealing and the sealing ring, and directly welds the inlet pipe 352 and the return pipe 354 to the water cooling plate 34, which can effectively avoid the risk of pipe joint failure in a vacuum high temperature environment.

[0064] The water cooling plate 34 includes an upper water cooling plate 341, a water cooling plate connecting pipe 342, and a lower water cooling plate 343. The upper water cooling plate 341 and the lower water cooling plate 343 are connected by the water cooling plate connecting pipe 342, and water flows between the upper water cooling plate 341 and the lower water cooling plate 343 through the connecting pipe 22.

[0065] The upper plate 341 and the lower plate 343 of the water-cooling jacket are respectively provided with through cooling holes 340 and intermediate holes (not shown in the figure). During crystal pulling, as the seed crystal is lifted upward by the lifting device in the crystal preparation equipment, the seed crystal passes through the cooling holes 340. As its diameter gradually increases to form a silicon core, water flows in the water-cooling plate 34 to cool the seed crystal. The intermediate hole is insulated with graphite material, which completely solves the problem of thermal damage to the pulling device caused by the extremely high temperature of the hole heat radiation.

[0066] In this embodiment, the cooling holes 340 on the upper plate 341 of the water-cooling jacket and the cooling holes 340 on the lower plate 343 of the water-cooling jacket correspond one-to-one. There are a number of cooling holes 340, and the number can be set as needed. The cooling holes 340 are arranged in double rings inside and outside.

[0067] The upper plate 341 of the water-cooling jacket is provided with an upper water inlet cavity 3411 and an upper water return cavity 3412. The upper water inlet cavity 3411 and the upper water return cavity 3412 are separated by a partition, making them independent cavities. The water inlet is located on the upper water inlet cavity 3411. The lower plate 343 of the water-cooling jacket is provided with a lower water inlet cavity 3431 and a lower water return cavity 3432. The lower water inlet cavity 3431 and the lower water return cavity 3432 are separated by a partition, making them independent cavities. The outlet is located in the lower return water chamber 3432 of the water-cooling jacket. The upper water inlet chamber 3411 of the water-cooling jacket is connected to the lower water inlet chamber 3431, the lower water inlet chamber 3431 of the water-cooling jacket is connected to the lower return water chamber 3432 of the water-cooling jacket, and the upper return water chamber 3412 of the water-cooling jacket is connected to the lower return water chamber 3432 of the water-cooling jacket through the water-cooling jacket connecting pipe 342. The upper water inlet chamber 3411, the lower water inlet chamber 3431, the lower return water chamber 3432 of the water-cooling jacket and the upper return water chamber 3412 of the water-cooling jacket form a water flow channel, and water flows along the water flow channel.

[0068] The water-cooled jacket connecting pipe 342 has a hollow structure, and water flows along the hollow section. The connection between the water-cooled jacket connecting pipe 342 and the upper plate 341 and lower plate 343 of the water-cooled jacket is as follows:

[0069] The upper end of the water-cooled jacket connecting pipe 342 is connected to the lower end face of the water-cooled jacket connecting pipe 342, and the lower end is connected to the upper end face of the lower plate 343 of the water-cooled jacket. Multiple sets of water-cooled jacket connecting pipes 342 are provided; in this embodiment, four sets are provided, namely, the first connecting pipe 3421, the second connecting pipe 3422, the third connecting pipe 3423, and the fourth connecting pipe 3424. A flow chamber 3413 is provided between the upper water inlet chamber 3411 and the upper water return chamber 3412 of the water-cooled jacket. The flow chamber 3413 is connected by a partition... The plate is isolated from the upper water inlet cavity 3411 and the upper water return cavity 3412 of the water cooling jacket. The first connecting pipe 3421 connects the upper water inlet cavity 3411 and the lower water inlet cavity 3431 of the water cooling jacket. The second connecting pipe 3422 connects the flow chamber 3413 and the lower water inlet cavity 3431 of the water cooling jacket. The third connecting pipe 3423 connects the flow chamber 3413 and the lower water return cavity 3432 of the water cooling jacket. The fourth connecting pipe 3424 connects the upper water return cavity 3412 and the lower water return cavity 3432 of the water cooling jacket.

[0070] The water flow path in the water flow channel is as follows: water enters the upper water inlet chamber 3411 of the water-cooling jacket through the inlet, water in the upper water inlet chamber 3411 enters the lower water inlet chamber 3431 of the water-cooling jacket through the first connecting pipe 3421, water in the lower water inlet chamber 3431 enters the flow chamber 3413 through the second connecting pipe 3422, water in the flow chamber 3413 enters the lower return water chamber 3432 of the water-cooling jacket through the third connecting pipe 3423, water in the lower return water chamber 3432 enters the upper return water chamber 3412 of the water-cooling jacket through the fourth connecting pipe 3424, and then enters the return water structure through the outlet.

[0071] The cooling holes 340 of this application are arranged in double rings inside and outside, and the inlet and outlet of the water inlet and outlet are respectively located on both sides of the cooling holes 340. When water flows in the water flow channel, any cooling hole 340 can be cooled, ensuring uniform water circulation and uniform cooling between the upper plate 341 and the lower plate 343 of the water cooling jacket.

[0072] Water baffles 200 are provided in the upper water inlet cavity 3411, the upper water return cavity 3412, the lower water inlet cavity 3431, and the lower water return cavity 3432 of the water cooling jacket. The direction of water flow is controlled by the water baffles 200 to prevent stagnant water and thus improve the flow effect of water in the water cooling plate 34.

[0073] The lower surface of the water-cooling jacket lower plate 343, that is, the end face opposite to the graphite crucible 131, is provided with screw holes 3433. The screw holes 3433 are connected to the heat insulation layer (not shown in the figure). The heat insulation layer provides heat insulation protection for the lower surface of the water-cooling jacket lower plate 343 to prevent heat radiation from directly corroding the weak points of the water-cooling jacket lower plate 343. On the other hand, it prevents the water-cooling jacket from accidentally immersing into the graphite crucible 131 and directly exploding.

[0074] In other embodiments, the structures of the two sets of water-cooled plate assemblies 33 may be different or completely different.

[0075] In other embodiments, the inlet pipe 352 and the outlet pipe 34 can be set independently.

[0076] The lifting drive device 31 includes two sets, which are respectively connected to the auxiliary furnace chamber 12. The two sets of lifting drive devices 31 are respectively connected to two sets of water-cooled plate assemblies 33. The two sets of lifting drive devices 31 synchronously drive the water-cooled plate assemblies 33 to move up and down, thereby driving the porous water-cooled jacket 32 ​​to move.

[0077] The lifting drive device 31 can be a linear drive structure that can drive the porous water cooling jacket 32 ​​to move up and down, such as a ball screw drive structure, a motor synchronous belt drive structure, or a cylinder. This application does not limit it to this type.

[0078] When silicon material needs to be refilled, the lifting drive device 31 drives the porous water cooling jacket 32 ​​to move upward. The material cylinder connected to the porous water cooling jacket 32 ​​moves upward synchronously with the porous water cooling jacket 32, moving the porous water cooling jacket 32 ​​and the material cylinder into the auxiliary furnace chamber 12 for refilling. The rotary valve 14 closes to seal the main furnace chamber 11, thereby realizing the function of refilling silicon material without stopping the furnace during the pulling process by switching between the open and closed states of the rotary valve 14.

[0079] In this embodiment, the porous water-cooling jacket 32 ​​can be moved up and down by the lifting drive device 31. At the same time, the auxiliary furnace chamber 12 is detachably connected to the main furnace chamber 11. When it is necessary to clean the porous water-cooling jacket 32, the lifting drive device 31 moves the porous water-cooling jacket 32 ​​into the auxiliary furnace chamber 12, the rotary valve 14 is closed to seal the main furnace chamber 11, the auxiliary furnace chamber 12 is disassembled, and the auxiliary furnace chamber 12 and the heat shield lifting device are simultaneously separated from the main furnace chamber 11. At this time, the lifting drive device 31 drives the porous water-cooling jacket 32 ​​to move down until it moves to the outside of the auxiliary furnace chamber 12. The condensate on the surface of the porous water-cooling jacket 32 ​​can then be cleaned with a cleaning rod. After cleaning, the auxiliary furnace chamber 12 and the heat shield lifting device are installed into the main furnace chamber 11 according to the above steps. The rotary valve 14 is then opened to continue crystal pulling, thereby realizing the function of cleaning without stopping the furnace, effectively preventing impurities from falling and ensuring the purity of the silicon liquid.

[0080] Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

Claims

1. A Czochralski-type circular silicon core growth furnace, characterized in that: The device includes a furnace body, a lifting and rotating device, a multi-axis lifting plate device, and a heat shield lifting device. The furnace body includes a main furnace chamber and an auxiliary furnace chamber, which are detachably connected to the main furnace chamber. The lifting and rotating device includes a crystal lifting mechanism and a rotating mechanism. The multi-axis lifting plate device includes a housing and a gear transmission mechanism located inside the housing. The crystal lifting mechanism is connected to the housing, and the rotating mechanism is connected to the gear transmission mechanism. The gear transmission mechanism connects multiple sets of seed crystals. The heat shield lifting device includes a lifting drive device and a porous water-cooling jacket connected to the lifting drive device.

2. The Czochralski-grown circular silicon core growth furnace according to claim 1, characterized in that: The main furnace chamber is connected to a rotary vane valve, which is located between the auxiliary furnace chamber and the main furnace chamber. The opening and closing of the rotary vane valve controls the connection between the main furnace chamber and the auxiliary furnace chamber. A heating device is installed in the main furnace chamber. The heating device includes a quartz crucible and a graphite support rod connected to the quartz crucible. The graphite support rod is slidably connected to the main furnace chamber.

3. The Czochralski-type circular silicon core growth furnace according to claim 1, characterized in that: The crystal pulling mechanism includes a lifting mechanism and a tungsten wire rope connected to the lifting mechanism. One end of the tungsten wire rope is wound around a lifting winding shaft, and the other end is connected to the housing. The rotating mechanism includes a cable winding mechanism and a rotary motor. The cable winding mechanism is connected to the auxiliary furnace chamber, and the rotary motor is linked with multiple sets of seed crystals.

4. The Czochralski-type circular silicon core growth furnace according to claim 1, characterized in that: The heat shield lifting device is connected to the auxiliary furnace chamber. The heat shield lifting device includes a lifting drive device and a porous water-cooled jacket. The lifting drive device is connected to the porous water-cooled jacket and the auxiliary furnace chamber. The lifting drive device controls the porous water-cooled jacket to move up and down.

5. A Czochralski-type circular silicon core growth furnace according to claim 4, characterized in that: The porous water cooling jacket includes at least two sets of water cooling plate assemblies. Each water cooling plate assembly includes a water cooling plate and a water inlet / outlet device connected to the water cooling plate. The water cooling plate is provided with a water flow channel communicating with the water inlet / outlet device. The water cooling plates of the two sets of water cooling plate assemblies are connected.

6. A Czochralski-type circular silicon core growth furnace according to claim 5, characterized in that: The water inlet and return device includes a water inlet structure and a water return structure. The water inlet structure and the water return structure are respectively connected to the water flow channel of the water cooling plate. The water inlet structure, the water flow channel and the water return structure constitute the water inlet and return channel.

7. A Czochralski-type circular silicon core growth furnace according to claim 5, characterized in that: The inlet and outlet water device also includes a regulating device, which includes a temperature flow meter and an over-temperature switch. The temperature flow meter and the over-temperature switch are installed on the outlet water structure. The over-temperature switch is connected to the temperature flow meter, and the temperature flow meter detects the real-time water flow rate and temperature of the outlet water.

8. A Czochralski-type circular silicon core growth furnace according to claim 5, characterized in that: The water-cooling plate includes an upper water-cooling jacket plate, a water-cooling jacket connecting pipe, and a lower water-cooling jacket plate, with the upper and lower water-cooling jacket plates connected by the water-cooling jacket connecting pipe.

9. A Czochralski-type circular silicon core growth furnace according to claim 8, characterized in that: The upper plate of the water-cooling jacket is provided with an upper water inlet chamber and an upper water return chamber, and the lower plate of the water-cooling jacket is provided with a lower water inlet chamber and a lower water return chamber. The upper water inlet chamber and the lower water inlet chamber, the lower water inlet chamber and the lower water return chamber, and the upper water return chamber and the lower water return chamber are respectively connected through water-cooling jacket connecting pipes. The upper water inlet chamber, the lower water inlet chamber, the lower water return chamber, and the upper water return chamber constitute a water flow channel.

10. A Czochralski-grown circular silicon core growth furnace according to claim 4, characterized in that: The lifting drive device includes two sets, which are respectively connected to the auxiliary furnace chamber and respectively connected to two sets of water-cooled plate assemblies.

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