Integrated device for crystal pulling cooling and feeding preheating of single crystal furnace

Abstract

The invention discloses an integrated device for crystal pulling cooling and feeding preheating of a single crystal furnace, and mainly relates to a vortex tube connected with an air compressor. Normal-temperature and high-pressure gas output by the air compressor is separated into cold gas and hot gas through the vortex tube, the cold gas and the hot gas are used for cooling crystals and heating crystal pulling raw materials respectively, and the safety of a cooling system and the stability of the continuous crystal pulling process can be improved. And the baffle plates are arranged in the cold air pipeline and the hot air pipeline, so that the heat exchange capacity is enhanced, and the heat exchange effect is enhanced. A temperature measurement-feedback-regulation and control integrated device is arranged, the power of an air compressor and the output of a vortex tube are calculated, fed back and adjusted based on the actual cooling and heating effect, and crystal pulling cooling and feeding preheating are cooperatively regulated and controlled. By arranging the main gas storage tank, cold gas and hot gas are collected and injected into the air compressor again, gas heat energy is fully utilized, energy consumption is reduced, meanwhile, gas emission is reduced, the purpose of reducing cost is achieved, and good economical efficiency is achieved.

Description

Technical Field:

[0001] The present invention belongs to the field of Czochralski single crystal furnace devices, and particularly relates to an integrated device for crystal pulling cooling and feeding preheating of a single crystal furnace. Background Art:

[0002] Crystalline silicon is one of the main raw materials for solar cells in the photovoltaic industry and is also a raw material for semiconductor wafer processing and manufacturing. It is an indispensable part of the green energy and semiconductor industries. At present, the continuous feeding technology has broad application prospects in the preparation of low-cost and high-quality Czochralski single crystals. However, most of the current continuous feeding Czochralski single crystal furnaces usually use water cooling for crystal bar cooling, which has certain safety risks. At the same time, there is no preheating process when automatically feeding silicon raw materials, resulting in significant thermal disturbance of the silicon melt in the crucible during continuous feeding, which easily leads to the interruption of the continuous crystal pulling process. Therefore, we propose an integrated device for crystal pulling cooling and feeding preheating of a Czochralski single crystal furnace based on gas. Summary of the Invention:

[0003] In view of the deficiencies of the prior art, the present invention provides an integrated device for crystal pulling cooling and feeding preheating of a single crystal furnace, which solves the problems raised in the above background art.

[0004] To achieve the above objectives, the present invention is realized through the following technical solutions:

[0005] An integrated device for crystal pulling cooling and feeding preheating of a single crystal furnace includes a vortex tube. The inlet of the vortex tube is connected to an air compressor. The cold end outlet of the vortex tube is connected to a cold air pipe, and a regulating valve is provided at the hot end outlet of the vortex tube and is connected to a hot air pipe. The cold air pipe spirally surrounds the crystal pulling cooling pipe, and the hot air pipe spirally surrounds the feeding preheating pipe. Crystals are passed through the inside of the crystal pulling cooling pipe, and crystal pulling raw materials are passed through the inside of the feeding preheating pipe. The lower parts of the crystal pulling cooling pipe and the feeding preheating pipe are the melt placed in the crucible. The cold air pipe and the hot air pipe are connected to a total gas storage tank, and the total gas storage tank is connected to the air compressor. Temperature measuring devices are provided on the outer walls of the cold air pipe and the hot air pipe, and the temperature measuring devices are connected to a calculation unit. The calculation unit is connected to the air compressor and the regulating valve in the vortex tube through a feedback circuit.

[0006] A further improvement of the present invention is that baffle plates are provided on the inner walls of the cold air pipe and the hot air pipe to enhance the heat exchange performance.

[0007] A further improvement of the present invention is that the temperature information of the temperature measuring device is input into the calculation unit and calculated using an intelligent algorithm to obtain feedback information, and the power of the air compressor and the opening degree of the regulating valve in the vortex tube are adjusted through the feedback circuit to adjust the air flow temperature and flow rate of the cold air pipe and the hot air pipe, so that the temperatures of the crystal pulling cooling pipe and the feeding preheating pipe reach the target values.

[0008] A further improvement of the present invention lies in that the air compressor uses one of argon, helium or air as the compressed gas for air supply.

[0009] A further improvement of the present invention lies in that the main gas storage tank is connected to the air compressor to collect the gases in the cold air pipe and the hot air pipe and re-inject them into the air compressor for recycling.

[0010] The present invention has the following beneficial effects:

[0011] The present invention provides a design solution for an integrated device for crystal pulling cooling and feeding preheating in a single crystal furnace. The gas is divided into cold air and hot air through a vortex tube. The cold air is used to cool the crystal, avoiding the risk of cooling water leakage caused by pipeline rupture when using liquid water for cooling, and improving the safety of the cooling system. In addition, the hot air is used to heat the crystal pulling raw materials, reducing the thermal disturbance to the silicon melt in the crucible caused by the feeding of low-temperature raw materials, and improving the stability of the continuous crystal pulling process. At the same time, baffle plates are arranged in the cooling and heating pipelines to further enhance heat transfer. In addition, the present invention further designs a temperature measurement - feedback - regulation integrated solution, and uses an intelligent algorithm to adjust the power of the air compressor and the output effect of the vortex tube, which can intelligently and coordinately regulate crystal pulling cooling and feeding preheating. In addition, by setting up a main gas storage tank, the gases in the cold air pipe and the hot air pipe are collected and re-injected into the air compressor, which can make full use of the gas thermal energy and reduce energy consumption. At the same time, the purpose of reducing gas emissions and lowering costs is achieved, and it has good economic efficiency. Description of the Drawings:

[0012] Figure 1 It is a schematic diagram of the integrated device of the present invention.

[0013] Figure 2 It is a schematic diagram of the vortex tube of the present invention.

[0014] Figure 3 It is a schematic diagram of the baffle plates inside the cold air pipe and the hot air pipe of the present invention.

[0015] In the figure: 1. Air compressor; 2. Vortex tube; 3. Cold air pipe; 4. Hot air pipe; 5. Crystal pulling cooling pipeline; 6. Feeding preheating pipeline; 7. Crystal; 8. Crystal pulling raw materials; 9. Crucible; 10. Melt; 11. Main gas storage tank; 12. Temperature sensor; 13. Calculation unit; 14. Feedback circuit; 15. Vortex tube inlet; 16. Vortex tube cold end outlet; 17. Vortex tube hot end outlet; 18. Vortex tube regulating valve; 19. Baffle plate. Detailed Embodiments:

[0016] The present invention will be further described in detail below with reference to the drawings.

[0017] As Figures 1 to 3As shown in the figure, an integrated device for single crystal furnace crystal pulling cooling and feeding preheating mainly involves a vortex tube 2. The inlet 15 of the vortex tube 2 is connected to an air compressor 1. The air compressor 1 outputs normal temperature and high-pressure gas, which enters the vortex tube 2 through the inlet 15. Inside the vortex tube 2, the gas is separated into cold air and hot air, which flow to the cold air pipe 3 and the hot air pipe 4 through the cold end outlet 16 and the hot end outlet 17 respectively. The cold air pipe 3 and the hot air pipe 4 are respectively spirally wound around the crystal pulling cooling pipe 5 and the feeding preheating pipe 6 to cool the crystal 7 and heat the crystal pulling raw material 8. At the same time, baffle plates 19 are arranged on the inner walls of the cold air pipe 3 and the hot air pipe 4 to disrupt the internal gas flow and further enhance the heat exchange effect. To make full use of the gas thermal energy and reduce energy consumption, and at the same time achieve the purpose of reducing gas emissions and lowering costs, a total gas storage tank 11 is set up to collect the gas in the cold air pipe 3 and the hot air pipe 4 and re-inject it into the air compressor 1 for recycling. Further, temperature detectors 12 are arranged on the outer walls of the crystal pulling cooling pipe 5 and the feeding preheating pipe 6 to monitor the temperatures of the crystal pulling cooling pipe 5 and the feeding preheating pipe 6 in real time, and input them into the calculation unit 13. The feedback information is calculated by using an intelligent algorithm. By adjusting the power of the air compressor 1 and the opening degree of the regulating valve 18 in the vortex tube 2, the air flow temperature and flow rate of the cold air pipe 3 and the hot air pipe 4 are adjusted to make the temperatures of the crystal pulling cooling pipe 5 and the feeding preheating pipe 6 reach the target values, so as to achieve the purpose of intelligent control of crystal pulling cooling and feeding preheating.

[0018] The above is only the preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution of the present invention and its inventive concept, makes equivalent replacements or changes, and all should be covered by the protection scope of the present invention.

Claims

1. An integrated device for crystal pulling cooling and material preheating in a single crystal furnace, comprising a vortex tube (2), wherein an inlet (15) of the vortex tube (2) is connected to an air compressor (1), a cold end outlet (16) of the vortex tube (2) is connected to a cold air pipe (3), a hot end outlet (17) of the vortex tube (2) is provided with a regulating valve (18) and is connected to a hot air pipe (4); the cold air pipe (3) spirally surrounds a crystal pulling cooling pipe (5), and the hot air pipe (4) spirally surrounds a material preheating pipe (6); a crystal (7) is passed through the crystal pulling cooling pipe (5), and a hot air pipe (4) is passed through the material preheating pipe (6); The crystal pulling raw material (8) is passed through the crystal pulling cooling pipe (5) and the feeding preheating pipe (6), and the lower part is the melt (10) contained in the crucible (9); the cold air pipe (3) and the hot air pipe (4) are connected to the main gas storage tank (11), and the main gas storage tank (11) is connected to the air compressor (1); the outer walls of the crystal pulling cooling pipe (5) and the feeding preheating pipe (6) are provided with a temperature detector (12), and the temperature detector (12) is connected to the calculation unit (13), and the calculation unit (13) is connected to the air compressor (1) and the regulating valve (18) in the vortex tube (2) through a feedback circuit (14).

2. The integrated device for cooling crystal pulling and preheating materials in a single crystal furnace according to claim 1, characterized in that: Baffles (19) are provided on the inner walls of the cold air pipe (3) and the hot air pipe (4) to enhance the heat exchange performance.

3. The integrated device for cooling crystal pulling and preheating materials in a single crystal furnace according to claim 1, characterized in that: The temperature information of the temperature detector (12) is input into the calculation unit (13) and the intelligent algorithm is used to calculate the feedback information. The power of the air compressor (1) and the opening of the regulating valve (18) in the vortex tube (2) are adjusted through the feedback circuit (14) to adjust the air flow temperature and flow rate of the cold air pipe (3) and the hot air pipe (4), so that the temperature of the crystal pulling cooling pipe (5) and the feeding preheating pipe (6) reaches the target value.

4. The integrated device for cooling crystal pulling and preheating materials in a single crystal furnace according to claim 1, characterized in that: The air compressor (1) uses argon, helium or air as compressed gas for supply.

5. The integrated device for cooling crystal pulling and preheating materials in a single crystal furnace according to claim 1, characterized in that: The main gas storage tank (11) is connected to the air compressor (1), collects the gas in the cold air pipe (3) and the hot air pipe (4), and re-injects the gas into the air compressor (1) for recycling.

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