Water-cooled heat shield device and crystal furnace

Abstract

The utility model discloses a water-cooled heat shield device and a crystal furnace, the water-cooled heat shield device comprises a heat shield body, a plurality of crystal pulling channels and a medium channel, the plurality of crystal pulling channels penetrate through at least part of the heat shield body, and the crystal pulling channels are used for moving crystal bars; the medium channel is located in the heat shield body, and at least part of the crystal pulling channel is coated with the medium channel; an inlet of the water outlet channel is communicated with the containing cavity, and the inlet of the water outlet channel is higher than an outlet of the water inlet channel. The utility model aims to provide the water-cooled heat shield device, and the cooling efficiency of the water-cooled jacket can be improved based on the device.

Description

Technical Field

[0001] This application relates to the field of crystal rod growth cooling technology, and in particular to a water-cooled heat shield device and a crystal furnace. Background Technology

[0002] Taking polycrystalline / monocrystalline silicon as an example, the amount of silicon core used in the entire production process of polycrystalline / monocrystalline silicon is very large. Most existing crystal rods are prepared by zone melting (mainly through high-frequency coils and seed crystal chucks to complete the pulling process). The working principle is as follows: When working, a high-frequency current is passed through the high-frequency coil, and high-frequency induction heating is performed, so that the high-frequency coil generates current and produces magnetic lines of force on the raw material rod. The upper end of the heated raw material rod forms a melting zone. Then, the seed crystal is inserted into the melting zone. When the end of the seed crystal is fused with the melting zone of the raw material rod, the seed crystal is slowly lifted. The molten raw material liquid will rise with the seed crystal to form a new columnar crystal rod. This new columnar crystal rod is the finished product of the crystal rod.

[0003] During crystal ingot pulling, a water-cooled jacket is usually placed above the crucible to cool the crystal ingot. In the prior art, the water-cooled jacket is placed outside the crystal ingot, and the crystal ingot is cooled by the cooling medium flow channel set in the water-cooled jacket. In order to improve the crystal pulling efficiency, it is sometimes necessary to pull multiple crystal ingots at one time. When the number of crystal ingots is large, especially more than thirty, the existing water-cooled jacket has low cooling efficiency for multiple crystal ingots.

[0004] Therefore, the problem with the existing technology is that the water-cooled jacket has low cooling efficiency. Utility Model Content

[0005] In order to overcome the shortcomings of the prior art, the purpose of this application is to provide a water-cooled heat shield device, which can improve the cooling efficiency of the water-cooled jacket.

[0006] To achieve the above objectives, this application provides a water-cooled thermal shield device, including a thermal shield body, a crystal pulling channel, and a dielectric channel. The crystal pulling channel passes through at least a portion of the thermal shield body and is used for moving a crystal rod. The dielectric channel is located within the thermal shield body and covers at least a portion of the crystal pulling channel.

[0007] Preferably, the medium channel includes a accommodating cavity, an inlet channel, and an outlet channel; the outlet of the inlet channel is connected to the accommodating cavity; the inlet of the outlet channel is connected to the accommodating cavity, and the inlet of the outlet channel is higher than the outlet of the inlet channel.

[0008] Preferably, the heat shield body includes a first part, a second part, and a third part arranged in a vertical direction; the third part is disposed between the first part and the second part; wherein the crystal pulling channel passes through the first part and the second part, and the crystal pulling channel is disposed outside the third part.

[0009] Preferably, the third part includes multiple inlet pipes and return pipes, the inlet pipes forming part of the inlet channel, and the return pipes communicating with the first accommodating cavity and the second accommodating cavity respectively.

[0010] Preferably, the water inlet channel includes at least one diversion cavity, which is disposed in the first part. The diversion cavity includes multiple outlets, and the multiple outlets of the diversion cavity are respectively connected to the inlets of the multiple water inlet pipes.

[0011] Preferably, the diversion cavity is located at the bottom of the first receiving cavity, and the return water pipe passes through the receiving cavity and is connected to the first receiving cavity.

[0012] Preferably, the water-cooled heat shield device further includes at least one liquid distribution plate, which is disposed in the receiving cavity. The liquid distribution plate is provided with multiple flow equalization channels, which are disposed towards the top of the first receiving cavity. The liquid distribution plate is used for uniform liquid distribution.

[0013] Preferably, the crystal pulling channel passes through at least the first part and the second part, and multiple crystal pulling channels are arranged in a ring or radial pattern on the outside of the third part.

[0014] Preferably, it further includes a gas guiding assembly, which includes a gas guiding pipe and a gas guiding sleeve. The gas guiding pipe extends axially through the first part, and the outlet of the gas guiding pipe is located at the center of the third part. The gas guiding sleeve is disposed on the upper surface of the second part and is used to form part of the crystal pulling channel. The gas guiding sleeve includes at least one gas inlet, which is disposed towards the gas guiding pipe.

[0015] This application also provides a crystal furnace, which includes: a furnace body, a crucible, a crystal pulling device, and a water-cooled heat shield device as described above. The crucible is disposed in the furnace body; the crystal pulling device is disposed in the furnace body and located above the crucible; the water-cooled heat shield device is disposed between the crucible and the crystal pulling device.

[0016] It has the following technical effects:

[0017] This application provides a water-cooled heat shield device, including multiple crystal pulling channels passing through the heat shield body and a medium channel disposed within the heat shield body. When the medium channel is disposed within the heat shield body, the distance between the medium channel and each crystal pulling channel is closer, which means that the medium channel can cool the crystal rod in each crystal pulling channel individually. Moreover, the medium channel at least covers part of the crystal pulling channel. When the cooling medium in the medium channel flows, it can carry away the heat of the crystal rod more quickly, thereby improving the cooling efficiency of the water-cooled heat shield device. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a water-cooled heat shield device in an embodiment of this application;

[0019] Figure 2 This is a top view of a water-cooled heat shield device according to an embodiment of this application;

[0020] Figure 3 for Figure 2 A cross-sectional view along the AA direction;

[0021] Figure 4 This is a cross-sectional view of another water-cooled heat shield device in the embodiments of this application;

[0022] Figure 5 This is a schematic diagram of the liquid separator plate in the water-cooled heat shield device of this application embodiment;

[0023] Figure 6 This is a schematic diagram of a crystal furnace according to an embodiment of this application.

[0024] Explanation of reference numerals in the attached drawings: 100, heat shield body; 110, first part; 120, second part; 130, third part; 131, water inlet pipe; 132, water return pipe; 200, crystal pulling channel; 300, medium channel; 310, accommodating cavity; 311, first accommodating cavity; 312, second accommodating cavity; 320, water inlet channel; 321, flow distribution cavity; 322, flow distribution channel; 330, water outlet channel; 400, liquid distribution plate; 410, flow equalization channel; 500, gas guiding assembly; 510, gas guiding pipe; 530, gas guiding sleeve; 600, furnace body; 700, crucible; 800, crystal pulling device. Detailed Implementation

[0025] To enable those skilled in the art to better understand the present application, the technical solutions in specific embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0026] It should be noted that, in the embodiments of this application, the terms "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design scheme described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design schemes. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a specific manner. The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0027] To address the problems in the prior art, this application provides a water-cooled heat shield device and a crystal furnace. The water-cooled heat shield device provided in this application will be described in detail below through specific embodiments.

[0028] Please refer to Figure 1 A water-cooled heat shield device includes: a heat shield body 100, a crystal pulling channel 200, and a medium channel 300. The crystal pulling channel 200 passes through at least a portion of the heat shield body 100 and is used for moving crystal rods. The medium channel 300 covers at least a portion of the crystal pulling channel 200 and is located within the heat shield body 100. The medium channel 300 includes: a accommodating cavity 310, a water inlet channel 320, and a water outlet channel 330. The accommodating cavity 310 covers at least a portion of the crystal pulling channel 200. The outlet of the water inlet channel 320 is connected to the accommodating cavity 310. The inlet of the water outlet channel 330 is connected to the accommodating cavity 310, and the inlet of the water outlet channel 330 is higher than the outlet of the water inlet channel 320.

[0029] Specifically, when the heat shield body 100 is installed in the furnace body 600, the axis of the heat shield body 100 is arranged vertically. In this application, the top of the heat shield body 100 refers to the end of the heat shield body 100 near the furnace opening when it is installed in the furnace body 600. The crystal pulling channel 200 is at least partially provided through the heat shield body 100. The crystal pulling channel 200 is used for the movement of the crystal rod during the crystal rod growth process. In this application, the crystal pulling channel 200 is preferably a circular tubular channel. The orientation of the crystal pulling channel 200 can be vertical or relatively inclined to the vertical. The number of crystal pulling channels 200 needs to be arranged according to the actual situation.

[0030] A medium channel 300 is disposed in the heat shield body 100 and is used for the flow of a cooling medium (such as coolant, pure water, or other cooling fluids). A receiving cavity 310 is located within the heat shield body 100 and is used to contain the cooling fluid. The receiving cavity 310 covers at least part of the aforementioned crystal pulling channel 200, so that when the fluid in the receiving cavity 310 flows, it can carry away the heat in the crystal pulling channel 200 through contact, and at the same time, it can form a heat shield to isolate the heating element from the influence of other components. It is conceivable that in order to better exert the cooling effect, the larger the proportion of the receiving cavity 310 in the heat shield body 100, the better. The medium channel 300 in this application also includes an inlet channel 320 and an outlet channel 330. The inlet of the outlet channel 330 is connected to an external high-pressure cooling medium supply device, and the outlet of the inlet channel 320 is connected to the accommodating cavity 310. Therefore, high-pressure and high-speed cooling medium can be transported into the accommodating cavity 310. The outlet of the outlet channel 330 is connected to an external pumping device, and the inlet of the inlet channel 320 is connected to the accommodating cavity 310. After the cooling medium enters the accommodating cavity 310, it can be discharged through the outlet channel 330.

[0031] In this application, the outlet of the water inlet channel 320 is located at the lower end of the inlet of the water outlet channel 330. That is, when the water-cooled heat shield device is working, the fluid first flows in from the lower part of the accommodating cavity 310, then flows upward to the inlet of the water outlet channel 330 located at the upper part of the accommodating cavity 310, forming a complete cooling medium flow path. Since bubbles inevitably form during the flow of the fluid medium, and these bubbles are less than the weight of the fluid medium, they move upward and eventually accumulate at the upper end of the medium channel 300. The arrangement in this application allows the bubbles that accumulate at the upper part of the accommodating cavity 310 to be discharged through the water outlet channel 330, solving the problem of bubbles not being able to be discharged in the prior art and improving cooling efficiency. Simultaneously, in this application, the flow direction of the cooling medium in the accommodating cavity 310 and most of the medium channels 300 is generally the same as the crystal pulling direction, which can improve the liquid surface temperature gradient distribution, optimize the cooling structure, and improve the cooling effect.

[0032] For further details, please refer to... Figure 2 The heat shield body 100 includes a first part 110, a second part 120 and a third part arranged in a vertical direction, with the third part 130 disposed between the first part 110 and the second part 120.

[0033] Specifically, in some embodiments, the heat shield body 100 includes a first portion 110, a second portion 120, and a third portion 130 spaced apart along the crystal pulling direction. The height of the first portion 110 is greater than the height of the second portion 120. The first portion 110 is barrel-shaped, and the barrel-shaped portion is used to cool the crystal rod in the crystal pulling channel 200 and prevent heat from diffusing to other parts and affecting other electronic components. The second portion 120 is preferably disk-shaped, and the disk-shaped arrangement is used to cool the crystal pulling channel 200 and at the same time to improve the temperature gradient distribution of the liquid surface. When the crystal pulling channel 200 passes through the first portion 110 and the second portion 120, a crystal pulling channel 200 is formed. When the crystal rod passes through the third portion 130, it is exposed, forming a visible part that can be used to observe the growth of the crystal rod. Preferably, the number of crystal pulling channels 200 in this application is more than 30. The crystal pulling channels 200 are divided into inner and outer rings, and both rings are arranged in a ring. At the same time, the crystal pulling channels 200 in the inner and outer rings are alternately arranged to better complete the heat dissipation process. The third part 130 is set in the ring group of crystal pulling channels 200 to better observe the growth of the crystal rod.

[0034] The third part 130 also includes: an inlet pipe 131 and a return pipe 132. The outlet of the inlet pipe 131 is connected to the second accommodating cavity 312, and the inlet pipe 131 is used to form a partial inlet channel 320. The inlet of the return pipe 132 is connected to the second accommodating cavity 312, and the outlet of the return pipe 132 is connected to the first accommodating cavity 311.

[0035] Specifically, in some embodiments, the third part 130 includes multiple hollow connecting pipes, which are connected to the first part 110 and the second part 120 respectively. According to the function of the connecting pipes, they can be divided into an inlet pipe 131 and a return pipe 132. The outlet of the inlet pipe 131 is connected to the second accommodating cavity 312, and the inlet pipe 131 serves as part of the inlet channel 320 to introduce liquid. The inlet of the return pipe 132 is connected to the second accommodating cavity 312, and the outlet of the return pipe 132 is connected to the first accommodating cavity 311.

[0036] Please refer to Figure 3-4The medium channel 300 also includes a first accommodating cavity 311 and a second accommodating cavity 312. The first accommodating cavity 311 is located in the first part 110 and is connected to the inlet of the water outlet channel 330. The second accommodating cavity 312 is located in the second part 120 and is connected to the outlet of the water inlet channel 320. The return water pipe 132 connects the first accommodating cavity 311 and the second accommodating cavity 312. Specifically, in one implementation, a first accommodating cavity 311 is disposed in a first part 110, and a second accommodating cavity 312 is disposed in a second part 120. The outlet of the water inlet channel 320 is connected to the second accommodating cavity 312, and the inlet of the water outlet channel 330 is connected to the first accommodating cavity 311. The cooling medium first flows into the second accommodating cavity 312 located in the second part 120 through the water inlet channel 320, and then flows into the first accommodating cavity 311 located in the first part 110 through the return water pipe 132, and then flows out from the water outlet channel 330, completing a complete cycle.

[0037] In another embodiment, the outlet of the water inlet channel 320 is connected to the first accommodating cavity 311, and the inlet of the water outlet channel 330 is connected to the first accommodating cavity 311. The cooling medium flows into the first accommodating cavity 311 and the second accommodating cavity 312 respectively. The cooling medium in the second accommodating cavity 312 flows back into the first accommodating cavity 311 located in the first part 110 through the return water pipe 132, completing a complete cycle.

[0038] Please refer to the figure. The inlet of the water inlet channel 320 is located at the top of the heat shield body 100. The water inlet channel 320 passes through at least the first part 110 and the third part 130. The water inlet channel 320 is used to supply cooling medium into the second accommodating cavity 312. Specifically, in one embodiment, the inlet of the water inlet channel 320 is located at the top of the heat shield body 100, that is, the part of the entire heat shield body 100 closest to the furnace opening. By setting the inlet of the water inlet channel 320 here, the gap that the external water inlet pipe has to pass through in the furnace body is smaller, which can protect the external water inlet pipe as much as possible and prevent the water inlet pipe from being damaged by the high temperature in the furnace. At the same time, the water inlet channel 320 passes through at least the first part 110 and the third part 130. The water inlet channel 320 enters from the top inlet and connects to the second accommodating cavity 312 located in the second part 120 to complete the circulation of the entire flow path.

[0039] In one embodiment, the outlet of the water outlet channel 330 and the inlet of the water inlet channel 320 are both located on the top of the heat shield body 100. When located on the top, it is easier to connect to external liquid supply and extraction devices to complete the liquid extraction and supply work.

[0040] Furthermore, the water inlet channel 320 includes at least one diversion cavity 321, which is disposed in the first part 110. The diversion cavity 321 includes multiple outlets and is used to divert the cooling medium. Specifically, in this embodiment, if the water inlet channel 320 needs to enter the second part 120 from the first part 110, the relatively long distance between the first part 110 and the second part 120 may lead to insufficient or uneven pressure. To ensure sufficient pressure, a diversion cavity 321 is also provided on the water inlet channel 320, preferably located at the bottom of the first part 110. Simultaneously, to ensure the stability of the cooling medium entering the second receiving cavity 312. Meanwhile, the flow distribution cavity 321 is provided with multiple outlets, which are evenly distributed. By providing multiple outlets, the water inlet channel 320, which originally had only one flow path, can be divided into multiple flow paths. Furthermore, by controlling the position and size of the openings, the flow rate and direction of the cooling medium in the water inlet channel 320 can be reasonably regulated. It is conceivable that, in order to correspond to the multiple outlets, the third part 130 includes multiple corresponding water inlet pipes 131. The inlet of the water inlet pipe 131 is connected to the outlet of the flow distribution cavity 321, so that the cooling medium enters the second accommodating cavity 312 in multiple directions.

[0041] Furthermore, the diversion cavity 321 is located at the bottom of the first receiving cavity 311. Specifically, in some embodiments, the diversion cavity 321 is located at the bottom of the first receiving cavity 311. As mentioned earlier, to ensure the cooling effect, the proportion of the receiving cavity 310 in the heat shield body 100 should be as large as possible, while ensuring that the cooling medium flowing through the diversion cavity 321 still has sufficient pressure. Therefore, the diversion cavity 321 is preferably located at the bottom of the first receiving cavity 311, which can ensure the pressure stabilization effect of the diversion cavity 321 as much as possible without affecting the proportion of the receiving cavity 310. At the same time, since the multiple outlets branched off from the diversion cavity 321 need to be connected to the water inlet pipe 131, this arrangement can also minimize the length of the water inlet pipe 131 and save production costs.

[0042] Please refer to Figure 5The water-cooled heat shield device also includes at least one distribution plate 400, which is disposed within the first receiving cavity 311. The distribution plate 400 has multiple flow equalization channels 410, which are oriented towards the top of the first receiving cavity 311. The distribution plate 400 is used for uniformly distributing the liquid. Specifically, the distribution plate 400 is disposed within the heat shield body 100, and the distribution plate 400 and the inner wall of the heat shield body 100 are detachably connected. The outline of the distribution plate 400 is the same as the outline of the inner wall of the heat shield body 100. The distribution plate 400 disposed within the heat shield body 100 can isolate multiple chambers within the heat shield body 100 to form the flow distribution chamber 321 and the return water chamber in the medium channel 300. In some embodiments, the distribution plate 400 has multiple flow equalization channels 410 evenly distributed on it, and all of the multiple flow equalization channels 410 are oriented in the same direction, towards the top of the heat shield body 100. As the cooling medium passes through the distributor plate 400, it is uniformly divided into multiple uniform fine streams by the multiple flow equalization channels 410 and flows into the next chamber. This eliminates the possibility of slack flow and improves the flow path of the cooling medium, thereby enhancing the cooling effect.

[0043] In one embodiment, the inner wall of the accommodating cavity 310 is provided with a plurality of stepped mounting portions, and the aforementioned liquid distribution plate 400 can be mounted on the stepped mounting portions. By providing a plurality of mounting portions, the liquid distribution plate 400 can be installed at different positions in this application. The specific position and size of each chamber in the heat shield body 100 can be arranged according to actual needs through the liquid distribution plate 400 at different positions, and further, different temperature gradient distributions can be constructed to adapt to different processing conditions.

[0044] Please refer to Figure 1 The water-cooled heat shield device also includes a gas guiding assembly 500, which includes a gas guiding pipe 510 and a gas guiding sleeve 530. The gas guiding pipe 510 axially passes through the first part 110, and the outlet of the gas guiding pipe 510 is located at the center of the third part 130. The gas guiding sleeve 530 is coaxially arranged with the crystal pulling channel 200 located in the second part 120, and the gas guiding sleeve 530 is used to form a part of the crystal pulling channel 200. The gas guiding sleeve 530 includes at least one air inlet. A baffle plate is provided between the first part 110 and the second part 120, and the baffle plate is located on the path of the gas guiding pipe 510. The baffle plate is used to introduce protective gas into the crystal pulling channel 200.

[0045] Specifically: During the crystal pulling process, an additional working gas (such as argon, helium, etc.) can be applied to uniformly blow protective gas onto the inner and outer ring crystal rods, suppressing oxide formation and improving the temperature gradient between the inner and outer ring crystal rods, thus optimizing the diameter difference between them. In one embodiment, the gas guide pipe 510 is preferably a graphite gas guide pipe 510, which is located in the center of the heat shield body 100 and penetrates the first part 110 of the heat shield body 100. The gas inlet of the gas guide pipe 510 is connected to an external gas supply unit. The outlet of the gas guide pipe 510 is located at the center of the third part 130 and is vertically downward; it also includes a gas guide sleeve 530, which is disposed on the upper surface of the second part 120. The gas guide sleeve 530 is used to form part of the crystal pulling channel 200. The gas guide sleeve 530 is preferably a semi-circular sleeve with a notch facing the gas guide pipe 510, so that the processing gas can flow into the gas guide sleeve 530 through the notch, further improving the growth rate of the crystal rod, suppressing the formation of inner ring oxide, improving the crystal rod quality, and reducing the diameter difference between the inner and outer ring crystal rods.

[0046] Please refer to Figure 6 This application also provides a crystal furnace, which includes: a furnace body 600, a crucible 700, a crystal pulling device 800, and a water-cooled heat shield device. The crucible 700 is disposed inside the furnace body 600; the crystal pulling device 800 is disposed inside the furnace body 600 and located above the crucible 700; and the water-cooled heat shield device is disposed between the crucible 700 and the crystal pulling device 800.

[0047] Specifically, the crystal furnace in this application is used to grow and pull crystal rods. The crystal furnace includes a furnace body 600, which is used to install other components and serves as the environment for the reaction; a crucible 700, in which silicon material is placed, which is used to grow crystal rods; a crystal pulling device 800, which is located above the opening of the crucible 700 and can complete the crystal core pulling process during its upward movement; and the aforementioned water-cooled heat shield device, which is located between the crystal pulling device 800 and the crucible 700, is used to control the temperature gradient changes during the crystal pulling process and to protect other electronic components inside the furnace body 600 from damage.

[0048] Technical effects:

[0049] 1. This application provides a water-cooled heat shield device, including multiple crystal pulling channels passing through the heat shield body and a medium channel disposed within the heat shield body and covering at least part of the crystal pulling channels. Through the medium channel disposed within the heat shield body, synchronous cooling can be performed on various positions within the entire heat shield body, ensuring that the crystallization rate of the crystal rods in the water-cooling tubes at each position is the same. This achieves the technical effect of improving the cooling efficiency of the water-cooling jacket when pulling multiple crystal rods at once, thereby ensuring the yield of the finished crystal rods.

[0050] 2. This application provides a water-cooled heat shield device, including a crystal pulling channel and a medium channel disposed outside the crystal pulling channel. The medium channel is used for the flow of cooling medium. The flow of cooling medium can form a cooling zone in the space above the crucible, forming a temperature gradient that is higher at the bottom and lower at the top. At the same time, by making the inlet of the water outlet channel higher than the outlet of the water inlet channel, the low-temperature part of the cooling zone is closer to the crucible, which can further reduce the temperature of the molten silicon above the crucible, increase the viscosity of the silicon liquid, and enable the silicon liquid to better follow the seed crystal crystallization, thereby increasing the crystal pulling speed.

[0051] 3. This application provides a water-cooled heat shield device, including a medium channel 300. The medium channel 300 is used for the flow of cooling medium. The flow of cooling medium removes heat during the growth of the crystal rod, thereby achieving the technical effect of cooling the crystal rod and providing heat shielding. By setting the inlet of the water outlet channel 330 higher than the outlet of the water inlet channel 320, the air bubbles generated by the medium fluid during the flow will accumulate in the upper part of the accommodating cavity 310 and be discharged through the relatively high outlet water outlet channel 330. This can better eliminate air bubbles in the medium channel 300, thereby ensuring the cooling effect of the water-cooled heat shield device in this application.

[0052] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A water-cooled heat shield apparatus, characterized by, The water-cooled heat shield device comprises a heat shield body, a crystal pulling channel and a medium channel, the crystal pulling channel passes through at least part of the heat shield body, and the crystal pulling channel is used for movement of a crystal bar; and the medium channel is located in the heat shield body and covers at least part of the crystal pulling channel.

2. The water-cooled heat shield apparatus of claim 1, wherein The medium channel (300) comprises: a containing cavity (310) covering at least part of the crystal pulling channel (200); a water inlet channel (320) having an outlet communicating with the containing cavity (310); and a water outlet channel (330) having an inlet communicating with the containing cavity (310), and the inlet of the water outlet channel (330) is higher than the outlet of the water inlet channel (320).

3. The water-cooled heat shield apparatus of claim 2, wherein, The heat shield body (100) comprises a first part (110), a second part (120) and a third part (130) arranged along a vertical direction, and the third part (130) is arranged between the first part (110) and the second part (120). The third part (130) comprises a plurality of water inlet pipes (131) and water return pipes (132), and the water inlet pipes (131) are used for forming part of the water inlet channel (320).

4. The water-cooled heat shield apparatus of claim 3, wherein The containing cavity (310) comprises: a first containing cavity (311) arranged in the first part (110) and communicating with the inlet of the water outlet channel (330); a second containing cavity (312) arranged in the second part (120) and communicating with the outlet of the water inlet channel (320); wherein the water return pipes (132) respectively communicate with the first containing cavity (311) and the second containing cavity (312).

5. The water-cooled heat shield apparatus of claim 4, wherein The inlet of the water inlet channel (320) is arranged at the top of the heat shield body (100), the water inlet channel (320) passes through at least the first part (110) and the third part, and the water inlet channel (320) is used for supplying cooling medium into the second containing cavity (312).

6. The water-cooled heat shield apparatus of claim 5, wherein The water inlet channel (320) comprises at least one shunt cavity (321) arranged in the first part (110), the shunt cavity (321) has a plurality of outlets, and the plurality of outlets of the shunt cavity (321) are respectively connected to the inlets of the plurality of water inlet pipes (131).

7. The water-cooled heat shield apparatus of claim 4, wherein The water-cooled heat shield device further comprises at least one liquid distribution plate (400) arranged in the first containing cavity (311), the liquid distribution plate (400) is provided with a plurality of uniform flow channels (410) arranged towards the top of the first containing cavity (311), and the liquid distribution plate (400) is used for uniform liquid distribution.

8. The water-cooled heat shield apparatus of claim 3, wherein The crystal pulling passages (200) at least pass through the first part (110) and the second part (120), and a plurality of the crystal pulling passages (200) are arranged annularly or radially outside the third part (130).

9. The water-cooled heat shield apparatus of claim 3, wherein, The water-cooled heat shield device further comprises a gas guide assembly (500), which comprises: a gas guide pipe (510) axially penetrating the first part (110), and an outlet of the gas guide pipe (510) being located at a central part of the third part (130); a gas guide sleeve (530) arranged on an upper surface of the second part (120), the gas guide sleeve (530) being used to form a part of the crystal pulling passage (200); and the gas guide sleeve (530) comprising at least one gas inlet, the gas inlet being arranged towards the gas guide pipe (510).

10. A crystal furnace characterized by comprising: The crystal furnace comprises: a furnace body (600); a crucible (700) arranged in the furnace body (600); a crystal pulling device (800) arranged in the furnace body (600) and located above the crucible (700); and a water-cooled heat shield device as claimed in any one of claims 1-9, which is arranged between the crucible (700) and the crystal pulling device (800).

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