Magnetic control directional crystallization process for self-adaptive magnetic field regulation and control in high-purity gallium production

Abstract

The invention discloses a self-adaptive magnetic field regulation and control magnetic control directional crystallization process in high-purity gallium production, which comprises the following steps: step 1, raw material pretreatment: putting a gallium raw material containing impurities into a smelting furnace, and heating to a temperature above a melting point, so that the gallium raw material is completely molten into liquid gallium; waste heat is recovered through a heat exchange device in the melting process and is used for preheating subsequent raw materials or other production links; 2, setting a self-adaptive magnetic field: transferring the liquid gallium into a crystallization container with a magnetic field generating device; step 3, accurate temperature control: arranging a plurality of coil heating units and water pipe cooling units outside the crystallization container, and arranging temperature sensors at different heights inside the crystallization container; step 4, crystal separation and post-treatment; the self-adaptive magnetic field regulation and control magnetic control directional crystallization process in high-purity gallium production can ensure the purity and quality of crystals through magnetic field regulation and control during use, can also effectively utilize the waste heat of equipment, reduces the production cost, and is suitable for popularization and application.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high-purity gallium production, and particularly relates to a magnetic control directional crystallization process with adaptive magnetic field regulation in high-purity gallium production. BACKGROUND

[0002] In the modern electronic industry, high-purity gallium, as a basic material for manufacturing semiconductor, integrated circuit, light-emitting diode and other key electronic devices, its purity and crystal quality play a decisive role in the performance of electronic devices. At present, the common high-purity gallium production methods such as electrolytic refining method, zone melting method, vacuum distillation method and directional crystallization method have certain limitations.

[0003] Although the traditional directional crystallization method can purify gallium to a certain extent, the control ability of the crystal growth direction and impurity distribution is limited in the crystal growth process, which leads to uneven quality of the produced high-purity gallium crystal, and it is difficult to meet the strict requirements of high-end electronic field on materials. And some technologies that try to improve the crystallization process by introducing magnetic field often use fixed magnetic field parameters, which cannot be adjusted in real time according to the change of material state in the crystallization process. This makes the magnetic field unable to play the best role in different crystallization stages, which not only affects the quality of the crystal, but also causes waste of energy. In addition, the existing technology has high energy consumption in the whole production process, and the waste heat cannot be effectively recycled, which further increases the production cost, and the operation effect is not ideal. SUMMARY

[0004] The purpose of the present application is to solve the above problems and provide a magnetic control directional crystallization process with adaptive magnetic field regulation in high-purity gallium production, which can ensure the purity and quality of the crystal through magnetic field regulation, and effectively utilize the waste heat of the equipment to reduce the production cost.

[0005] To achieve the above purpose, the technical scheme of the present application is as follows: a magnetic control directional crystallization process with adaptive magnetic field regulation in high-purity gallium production, comprising the following steps: Step one, raw material pretreatment: put the gallium raw material containing impurities into the furnace and heat it to above the melting point, so that it is completely melted into liquid gallium; in the melting process, the waste heat is recovered by heat exchange device for preheating the subsequent raw materials or other production links; Step two, adaptive magnetic field setting: transfer the liquid gallium to the crystallization container with magnetic field generating device; Step three, accurate temperature control: multiple coil heating units and water pipe cooling units are arranged outside the crystallization container, and temperature sensors are arranged at different heights inside the crystallization container, so as to accurately control the temperature gradient and cooling speed in the crystallization container; Step four, crystal separation and post-processing: after the completion of crystallization, the grown high-purity gallium crystal is separated from the remaining liquid impurities by physical methods, and the separated high-purity gallium crystal is cleaned and detected to ensure that the product quality meets the requirements.

[0006] Preferably, in the initial stage of crystallization in step two, the initial magnetic field strength and direction are set according to the initial state of the gallium raw material, wherein the initial magnetic field strength of the outer periphery of the crystallization container is 50-150 mT, the inner periphery magnetic field strength of the crystallization container is 5-30 mT, and the direction is perpendicular to the bottom surface of the container.

[0007] Preferably, the initial magnetic field strength is 100 mT, and when the crystal growth interface advances slowly and has a tendency to accumulate impurities, the magnetic field strength is increased to 120 mT, and the frequency is adjusted to 60 Hz.

[0008] Preferably, in step one, the furnace is heated to 40℃ at a heating rate of 10℃ / min until the gallium raw material melts.

[0009] Preferably, in step three, the top temperature of the crystallization container is controlled at 28±2℃, and the bottom temperature is controlled at 25±2℃, and the top temperature and the bottom temperature are both cooled at a cooling rate of 0.3℃ / h for crystallization.

[0010] Preferably, in step four, the physical method is any one of gravity sedimentation separation method, filtration separation method, decantation separation method and centrifugal separation method.

[0011] Preferably, the furnace is provided with a combustion chamber, the top of the furnace is provided with a crucible, the outer side of the furnace is provided with a heat exchanger, the input end of the heat exchanger is connected with the combustion chamber through a pipeline, and the output end of the heat exchanger is connected with a heat-using device.

[0012] Preferably, the heat exchanger is provided with an upper partition plate and a lower partition plate horizontally, the surface of the upper partition plate is provided with an intermediate partition plate, the edge of the intermediate partition plate is sealingly connected with the inner wall of the heat exchanger, a water return cavity is left below the lower partition plate, a plurality of communication pipes are arranged between the upper partition plate and the lower partition plate, the two sides of the intermediate partition plate are communicated with the water return cavity through the communication pipes, the top of the heat exchanger is further provided with a water inlet and a water outlet, and one end of the water return cavity is connected with a total exhaust pipe.

[0013] Preferably, the water inlet is arranged on one side close to the smoke exhaust pipe, the water outlet is arranged on one side close to the furnace, the heat exchanger is further provided with a pressure relief port, and the pressure relief port is arranged on the outer side of the water outlet.

[0014] Preferably, the heat exchanger is provided with a wind distribution plate on one side close to the furnace, and flow guide fin plates are arrayed on both sides of the inner wall of the heat exchanger, one side of the flow guide fin plate is fixed with the inner wall of the heat exchanger, and the other side is inclined to the smoke exhaust pipe.

[0015] The application discloses a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production, and comprises the following steps: step one, raw material pretreatment: placing impurity-containing gallium raw material into a furnace and heating to above the melting point to completely melt into liquid gallium; recovering waste heat through a heat exchange device during the melting process and using the waste heat to preheat subsequent raw materials or other production links; step two, self-adaptive magnetic field setting: transferring the liquid gallium to a crystallization container with a magnetic field generating device; step three, accurate temperature control: arranging a plurality of coil heating units and water pipe cooling units outside the crystallization container and arranging temperature sensors at different heights inside the crystallization container; and step four, crystal separation and post-treatment. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 The application discloses a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production Figure 1 .

[0017] Figure 2 The application discloses a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production Figure 2 .

[0018] Figure 3 The application discloses a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production Figure 2 .

[0019] Figure 4 The application discloses a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production

[0020] Figure 5 The application discloses a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production

[0021] In the figure: 1, furnace; 2, combustion chamber; 3, crucible; 4, heat exchanger; 5, upper partition plate; 6, lower partition plate; 7, middle partition plate; 8, water inlet; 9, water outlet; 91, pressure relief port; 10, water return chamber; 11, communication pipe; 12, air distribution plate; 13, total exhaust pipe; 14, exhaust pipe; 15, flow guide fin plate. DETAILED DESCRIPTION

[0022] The application will now be described in further detail, by way of example only, with reference to the accompanying drawings: - figure 1 is a schematic view of a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production, - figure 2 is a schematic view of a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production, - figure 3 is a schematic view of a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production, - figure 4 is a schematic view of a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production, - figure 5 is a schematic view of a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production, - figure 6 is a schematic view of a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production, - figure 7 is a schematic view of a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production, - figure 8 is a schematic view of a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production, - figure 9 is a schematic view of a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production, - figure 10 is a schematic view of a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production, - figure 11 is a schematic view of a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production, - figure 12 is a schematic view of a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production, - figure 13 is a schematic view of a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production, - figure 14 is a schematic view of a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production, and - figure 15 is a schematic view of a magnetic control directional crystallization process of self-adaptive magnetic field regulation in high-purity gallium production.

[0023] A magnetic control directional crystallization process with adaptive magnetic field regulation in high-purity gallium production, comprising the following steps: Step one, raw material pretreatment: put the impurity-containing gallium raw material into the furnace and heat it to above the melting point to completely melt it into liquid gallium; recover the waste heat through the heat exchange device during the melting process for preheating the subsequent raw materials or other production links; specifically, the furnace is heated to 40℃ at a heating rate of 10℃ / min until the gallium raw material melts; Step two, adaptive magnetic field setting: transfer the liquid gallium to a crystallization container with a magnetic field generating device; in the initial stage of crystallization, set the initial magnetic field strength and direction according to the initial state of the gallium raw material, wherein the initial magnetic field strength of the outer periphery of the crystallization container is 50-150mT, the inner periphery magnetic field strength of the crystallization container is 5-30mT, and the direction is perpendicular to the bottom surface of the container; the initial magnetic field strength is preferably 100mT, when the crystal growth interface advances slowly and there is a tendency for impurities to accumulate, the magnetic field strength is increased to 120mT, and the frequency is adjusted to 60Hz; Step three, precise temperature control: multiple coil heating units and water pipe cooling units are arranged outside the crystallization container, and temperature sensors are arranged at different heights inside the crystallization container to accurately control the temperature gradient and cooling speed in the crystallization container; wherein the top temperature of the crystallization container is controlled at 28±2℃, the bottom temperature is controlled at 25±2℃, and the top temperature and the bottom temperature are both cooled at a cooling speed of 0.3℃ / h for crystallization; Step four, crystal separation and post-treatment: after crystallization, the grown high-purity gallium crystal is separated from the remaining liquid impurities by physical methods, and the separated high-purity gallium crystal is cleaned and detected to ensure that the product quality meets the requirements, wherein the physical method is any one of gravity sedimentation separation method, filtration separation method, decantation separation method and centrifugal separation method, and the post-treatment equipment includes cleaning equipment and detection equipment for separating the high-purity gallium crystal from the impurities and subsequent processing of the crystal.

[0024] In step two, as the crystallization process proceeds, the temperature distribution of the liquid gallium, the crystal growth interface position, and the impurity concentration distribution are monitored in real time using sensors distributed inside the crystallization container. The control system automatically adjusts the magnetic field parameters through algorithm models based on these real-time monitoring data, achieving adaptive regulation of the magnetic field, ensuring that the magnetic field promotes crystal growth in the predetermined direction and effectively inhibits impurities from mixing into the crystal throughout the entire crystallization process.

[0025] The crystallization container is made of a high-temperature resistant, low-impurity material, providing a stable environment for gallium crystallization. The magnetic field generator can produce magnetic fields of varying intensities, directions, and frequencies, with parameters precisely controlled by the control system. A sensor array, including temperature, position, and concentration sensors, is distributed within the crystallization container to collect various data during the crystallization process in real time and transmit the data to the control system. Based on a preset algorithm model, the control system adjusts the parameters of the magnetic field generator in real time according to the data collected by the sensors, achieving adaptive control of the magnetic field.

[0026] The entire process utilizes adaptive magnetic field control, which can adjust the magnetic field parameters in real time according to the changes in the material state during crystallization. This effectively promotes crystal growth along a predetermined direction, reduces crystal defects, and lowers impurity content, thereby significantly improving the quality and purity of high-purity gallium crystals. The product purity can reach or even exceed 7N (99.99999%), meeting the stringent requirements for high-purity gallium in the high-end electronics field. Furthermore, the waste heat generated during the production process is effectively recovered and utilized for preheating raw materials or other production stages, reducing energy waste and lowering the overall energy consumption of the production process. On the other hand, adaptive magnetic field control enables optimal magnetic field conditions to promote crystallization during the crystallization process, avoiding excessive energy consumption caused by unreasonable magnetic field parameters. Compared with traditional processes, the technology of this invention can reduce energy consumption by 30%-50%.

[0027] Please refer to Figures 1-5 Based on the above embodiments, the furnace 1 is provided with a combustion chamber 2, and a crucible 3 is provided on the top of the furnace 1. The raw material gallium is melted in the crucible 3. A heat exchanger 4 is provided on the outside of the furnace 1. The input end of the heat exchanger 4 is connected to the combustion chamber 2 through a pipe, and the output end of the heat exchanger 4 is connected to the heat-using equipment. When in use, the high-temperature flue gas in the furnace 1 enters the heat exchanger 4 through the pipe, thereby heating the internal heat exchange medium to reduce energy consumption.

[0028] In this embodiment, the heat exchange medium is water or heat transfer oil.

[0029] The heat exchanger 4 is provided with an upper partition 5 and a lower partition 6 horizontally arranged inside. The surface of the upper partition 5 is provided with a middle partition 7, and the edge of the middle partition 7 is sealed to the inner wall of the heat exchanger 4. A return water chamber 10 is provided below the lower partition 6. Multiple connecting pipes 11 are provided between the upper partition 5 and the lower partition 6. Both sides of the middle partition 7 are connected to the return water chamber 10 through the connecting pipes 11. The top of the heat exchanger 4 is also provided with an inlet 8 and an outlet 9. One end of the return water chamber 10 is connected to a main drain pipe 13, which is normally closed and is opened by a valve when the heat exchanger 4 needs to be emptied.

[0030] In other words, the middle partition 7 divides the upper partition 5 into two areas: one is the water inlet area, and the other is the water outlet area. The water inlet is located above the water inlet area, and the water outlet is located above the water outlet area. After water enters through the water inlet 8, the water flows into the return water chamber 10 through the connecting pipe 11. At this time, as the external water source is continuously injected, the water in the return water chamber 10 will flow along the connecting pipe 11 towards the water outlet area and finally be discharged at the water outlet 9. During the flow of water in the connecting pipe 11, it comes into contact with the high-temperature flue gas. The pipe and the water inside absorb heat, reducing the temperature of the flue gas, thereby achieving heat exchange.

[0031] Specifically, the water inlet 8 is located on the side near the flue pipe 14. Inside the heat exchanger 4, the temperature of the flue gas decreases as it gets closer to the flue pipe 14. Therefore, the water source first passes through the low-temperature flue gas, and as water is continuously injected, it overflows into the high-temperature flue gas. The water outlet 9 is located on the side near the furnace 1. The heat exchanger 4 is also equipped with a pressure relief port 91, which is located outside the water outlet 9. After the heat exchange is completed, the hot water is discharged from the water outlet 9 to supply the heating equipment.

[0032] To ensure that the high-temperature flue gas is evenly blown into the heat exchanger 4, the heat exchanger 4 is provided with an air distribution plate 12 on the side near the furnace 1. The air distribution plate 12 is provided with evenly distributed through holes. In order to ensure that the flue gas in the heat exchanger 4 is blown towards the connecting pipe 11, the inner wall of the heat exchanger 4 is provided with a guide fin 15 arrayed on both sides. One side of the guide fin 15 is fixed to the inner wall of the heat exchanger 4, and the other side is inclined towards the exhaust pipe 14. Therefore, when the flue gas enters the heat exchanger 4, it will be split to both sides and blown towards the guide fin 15. The inclined guide fin 15 causes the flue gas to be blown towards the connecting pipe 11 again, and finally the flue gas is discharged from the exhaust pipe 14 after heat exchange.

[0033] Implementation Case: Raw material pretreatment: 100 kg of gallium raw material with a purity of 99% was placed in a furnace and heated to 40°C at a heating rate of 10°C / min until it was completely melted. During the melting process, the residual heat was transferred to the heat transfer oil through a heat exchanger, and the heat transfer oil stored the heat in a waste heat storage device. It was found that this waste heat recovery can save about 40% of the energy consumption for subsequent preheating of new raw materials.

[0034] Adaptive magnetic field setup and crystallization process: Molten liquid gallium is transferred to a crystallization container. Initially, the magnetic field strength is set to 100 mT, the magnetic field direction is perpendicular to the bottom surface of the crystallization container, and the frequency is 50 Hz. During the crystallization process, sensors monitor the state of the liquid gallium in real time. When the crystal growth interface propagation speed slows down and impurities show a tendency to aggregate, the control system automatically increases the magnetic field strength to 120 mT and adjusts the frequency to 60 Hz according to the algorithm model to promote crystal growth and impurity separation. Simultaneously, the temperature control system maintains the top temperature of the crystallization container at 28°C and the bottom temperature at 25°C, cooling the crystallizer at a cooling rate of 0.3°C / h.

[0035] Crystal Separation and Post-processing: After crystallization, a gravity separation device was used to separate the high-purity gallium crystal from the remaining liquid impurities, yielding 50 kg of high-purity gallium crystal with a purity of 99.999999%. The crystal was cleaned and tested, and the results showed that the crystal quality was good, with no obvious defects and extremely low impurity content, meeting the standards for use in high-end electronics.

[0036] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A magnetron-controlled directional crystallization process with adaptive magnetic field regulation for high-purity gallium production, characterized in that, Includes the following steps: Step 1, Raw material pretreatment: The gallium raw material containing impurities is placed in a furnace and heated above its melting point to completely melt it into liquid gallium; during the melting process, the residual heat is recovered through a heat exchange device and used to preheat subsequent raw materials or other production processes; Step 2, Adaptive Magnetic Field Setting: Transfer the liquid gallium to a crystallization container equipped with a magnetic field generator; Step 3: Precise Temperature Control: Multiple coil heating units and water pipe cooling units are installed on the outside of the crystallization container, and temperature sensors are installed at different heights inside the crystallization container to precisely control the temperature gradient and cooling rate inside the crystallization container; Step 4, Crystal Separation and Post-processing: After crystallization, physical methods are used to separate the grown high-purity gallium crystal from the remaining liquid impurities. The separated high-purity gallium crystal is then cleaned and tested to ensure that the product quality meets the requirements.

2. The adaptive magnetic field-controlled magnetodirectional crystallization process for high-purity gallium production according to claim 1, characterized in that, In step one, the furnace is heated to 40°C at a heating rate of 10°C / min until the gallium material melts.

3. The adaptive magnetic field-controlled magnetodirectional crystallization process for high-purity gallium production according to claim 1, characterized in that, In step two, during the initial stage of crystallization, the initial magnetic field strength and direction are set according to the initial state of the gallium raw material. The initial magnetic field strength around the outer perimeter of the crystallization container is 50-150 mT, and the magnetic field strength around the inner perimeter of the crystallization container is 5-30 mT, with the direction perpendicular to the bottom surface of the container.

4. The adaptive magnetic field-controlled magnetodirectional crystallization process for high-purity gallium production according to claim 1, characterized in that, The initial magnetic field strength was 100 mT. When the crystal growth interface propagation speed slowed down and there was a tendency for impurities to accumulate, the magnetic field strength was increased to 120 mT and the frequency was adjusted to 60 Hz.

5. The adaptive magnetic field-controlled magnetodirectional crystallization process for high-purity gallium production according to claim 1, characterized in that, In step three, the temperature at the top of the crystallization container is controlled at 28±2℃, and the temperature at the bottom is controlled at 25±2℃. Both the top and bottom temperatures are cooled and crystallized at a cooling rate of 0.3℃ / h.

6. The adaptive magnetic field-controlled magnetodirectional crystallization process for high-purity gallium production according to claim 1, characterized in that, The physical method in step four can be any one of gravity sedimentation separation, filtration separation, decantation separation, or centrifugal separation.

7. The adaptive magnetic field-controlled magnetodirectional crystallization process for high-purity gallium production according to any one of claims 1-6, characterized in that, The furnace is equipped with a combustion chamber, and a crucible is placed on top of the furnace. A heat exchanger is placed on the outside of the furnace. The input end of the heat exchanger is connected to the combustion chamber through a pipe, and the output end of the heat exchanger is connected to the heat-using equipment.

8. The adaptive magnetic field-controlled magnetodirectional crystallization process for high-purity gallium production according to claim 7, characterized in that, The heat exchanger is horizontally equipped with an upper partition and a lower partition. A middle partition is provided on the surface of the upper partition. The edge of the middle partition is sealed to the inner wall of the heat exchanger. A return water cavity is provided below the lower partition. Multiple connecting pipes are provided between the upper and lower partitions. Both sides of the middle partition are connected to the return water cavity through connecting pipes. The top of the heat exchanger is also provided with an inlet and an outlet. One end of the return water cavity is connected to a main drain pipe.

9. The adaptive magnetic field-controlled magnetodirectional crystallization process for high-purity gallium production according to claim 8, characterized in that, The water inlet is located on the side near the flue pipe, and the water outlet is located on the side near the furnace. The heat exchanger is also equipped with a pressure relief port, which is located outside the water outlet.

10. The adaptive magnetic field-controlled magnetodirectional crystallization process for high-purity gallium production according to claim 9, characterized in that, The heat exchanger has an air distribution plate on the side near the furnace, and the inner wall of the heat exchanger is provided with an array of flow guiding fins on both sides. One side of the flow guiding fins is fixed to the inner wall of the heat exchanger, and the other side is inclined towards the exhaust pipe.

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