Forming device for high-purity gallium particles

Abstract

A high-purity gallium particle forming device comprises a rack, a cooling tank with an upward opening is installed on the rack, cooling liquid is contained in the cooling tank, a conveyor is obliquely arranged in the cooling tank, the inlet end of the conveyor is arranged at the bottom of the cooling tank, and the outlet end of the conveyor is arranged on the outer side of the cooling tank. A high-purity gallium dropping device is arranged on the rack and above the inlet end of the conveyor, and an outlet of the high-purity gallium dropping device is arranged right above the inlet end of the conveyor. According to the utility model, the continuous operation of the conveyor is matched with the continuous rotation of the funnel driven by the turntable, so that the position of the high-purity gallium liquid dropped into the cooling agent is automatically changed, meanwhile, gallium particles are continuously conveyed out of the cooling tank by utilizing the conveyor, the formed gallium particles and unformed gallium sheets are timely separated, and the accumulation and adhesion are avoided.

Description

Technical Field

[0001] This utility model relates to the field of high-purity gallium particle preparation technology, and in particular to a high-purity gallium particle forming device. Background Technology

[0002] Gallium is a metallic element with the symbol Ga and atomic number 31, and it has a wide range of applications. In addition to being used in the preparation of semiconductors such as gallium nitride, gallium arsenide, and gallium phosphide, it is also mainly used as a dopant in semiconductor materials such as silicon and germanium. High-purity gallium particles are used as a dopant for single-crystal silicon wafers in the fabrication of solar cells, effectively solving the long-standing problem of light attenuation.

[0003] However, high-purity gallium exhibits supercooling, meaning that it remains liquid and does not solidify when the temperature drops below its melting point of 29.78°C. The higher the purity, the more severe the supercooling. In some cases, liquid high-purity gallium can even be cooled to -120°C without freezing.

[0004] Currently, the main manufacturing process for high-purity gallium granules involves dropping liquid gallium into a coolant. The buoyancy and weightlessness during the descent cause the gallium droplets to naturally shrink into small spheres, which then condense into solid particles. However, due to supercooling, some droplets fail to solidify upon hitting the bottom. If these droplets then solidify on already formed gallium granules, they will adhere together, leading to a lower yield.

[0005] Therefore, during the manufacturing process, it is necessary to prevent the gallium molten metal from dripping into the coolant in a fixed position, thereby avoiding the accumulation of particles in the same location. Chinese patent application CN111659897A proposes that moving the dispensing bottle horizontally at a speed of 3–9 cm / s during the dispensing process can solve this problem. However, this solution does not consider the timely transfer of the formed gallium particles, and accumulation will still occur over long periods of operation, leading to a decrease in yield and making it unsuitable for large-scale continuous production. Utility Model Content

[0006] This invention addresses the shortcomings of existing technologies by providing a molding device for high-purity gallium granules that can be mass-produced continuously while ensuring a high yield rate.

[0007] To achieve the above objectives, this utility model first proposes a high-purity gallium particle forming device, including a frame, a cooling tank with an upward opening installed on the frame, the cooling tank being filled with coolant, a conveyor being inclinedly installed in the cooling tank such that the inlet end of the conveyor is located at the bottom of the cooling tank and the outlet end is located outside the cooling tank, a high-purity gallium dropper is installed on the frame above the inlet end of the conveyor, and the outlet of the high-purity gallium dropper is located directly above the inlet end of the conveyor.

[0008] In this embodiment, the internal depth of the cooling tank is 800mm to 1000mm.

[0009] In this embodiment, a collection container is provided on the frame below the outlet end of the conveyor.

[0010] In this embodiment, the bottom plate and side walls of the collection container are both screens smaller than the size of high-purity gallium liquid particles.

[0011] In this embodiment, a plurality of barrier bars are fixed on the conveyor belt of the conveyor and arranged perpendicular to the conveying direction of the conveyor belt. Adjacent barrier bars enclose each other on the conveyor belt to form storage cells arranged continuously on the conveyor belt.

[0012] In this embodiment, the spacing between adjacent barrier bars is 150~200mm.

[0013] In this embodiment, the cooling tank is connected to a chiller, and the temperature of the cooling water in the cooling tank is controlled at 0~10℃.

[0014] In this embodiment, the high-purity gallium droplet device includes a turntable and a funnel for placing high-purity gallium liquid. The turntable is driven to rotate by a drive device. The turntable is provided with a plurality of mounting slots for mounting funnels. The funnels are installed in the mounting slots of the turntable, and valves are installed on the outlets of the funnels.

[0015] In this embodiment, the outlet of the funnel is positioned 1-10 mm below the surface of the coolant liquid.

[0016] In this embodiment, the rotational speed of the turntable is 100~200 r / min.

[0017] With the above structure, this utility model has the following advantages:

[0018] 1. Using a conveyor can separate formed and unformed gallium granules in a timely manner, thereby improving the yield rate.

[0019] 2. By coordinating the continuous operation of the conveyor with the continuous rotation of the funnel driven by the turntable, the position of the high-purity gallium liquid droplets entering the coolant is automatically changed, avoiding accumulation and adhesion.

[0020] 3. The conveyor belt is equipped with barrier strips to prevent high-purity gallium granules from falling during the conveying process and to effectively remove the high-purity gallium granules from the cooling tank.

[0021] In summary, this invention combines the continuous operation of the conveyor with the continuous rotation of the funnel driven by the turntable, causing the position of the high-purity gallium droplets entering the coolant to change automatically. Simultaneously, the conveyor continuously transports gallium granules from the cooling tank, promptly separating formed and unformed gallium granules and wafers, preventing accumulation and adhesion. This device not only significantly improves the production yield but also greatly simplifies user operation through automation. Attached Figure Description

[0022] Figure 1This is a schematic diagram of the structure of this utility model.

[0023] Figure 2 for Figure 1 Top view.

[0024] Figure 3 This is a side view of the turntable of this utility model.

[0025] In the attached diagram: 1. Funnel; 2. Turntable; 21. Mounting slot; 3. Drive unit; 4. Cooling tank; 5. Conveyor; 51. Barrier bar; 6. Collection container. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0027] Furthermore, the technical solutions of the various embodiments of this utility model can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0028] like Figures 1 to 3 As shown, a high-purity gallium particle forming apparatus includes a frame, on which an upward-opening cooling tank 4 is mounted. The cooling tank 4 is filled with coolant and has an internal depth of 800mm to 1000mm. A conveyor 5 is inclinedly disposed within the cooling tank 4, with its inlet end located at the bottom of the cooling tank 4 and its outlet end located outside the cooling tank 4. A high-purity gallium dropper is mounted on the frame above the inlet end of the conveyor 5, and the outlet of the high-purity gallium dropper is located directly above the inlet end of the conveyor 5. The width of the conveyor belt of the conveyor 5 covers the dripping area of ​​the high-purity gallium dropper. A collection container 6 is disposed on the frame below the outlet end of the conveyor 5.

[0029] like Figure 2As shown, in this embodiment, the conveyor 5 is a belt conveyor 5. Multiple blocking bars 51 are fixed on the conveyor belt of the conveyor 5 and arranged perpendicular to the conveying direction of the conveyor belt. Adjacent blocking bars 51 enclose and form storage cells continuously arranged on the conveyor belt. In use, high-purity gallium dripping from the outlet of the high-purity gallium dripping device is cooled by the cooling tank 4 to form solid high-purity gallium particles. The high-purity gallium particles fall into the storage cells of the conveyor belt. The storage cells prevent the high-purity gallium particles from falling off the conveyor belt during operation. The conveyor belt removes the high-purity gallium particles from the cooling tank 4. The high-purity gallium particles fall from the outlet of the conveyor 5 into the collection container 6. Finally, the high-purity gallium particles in the collection container 6 are rinsed with pure water and dried. Unformed gallium flakes are screened out, and gallium particles with qualified shape are packaged and sealed.

[0030] like Figure 3 As shown, the high-purity gallium dripping device includes a turntable 2 and funnels 1. The turntable 2 is driven to rotate by a drive device 3. The turntable 2 is provided with multiple mounting slots 21 for mounting funnels 1. High-purity gallium liquid is placed in the funnels 1. The funnels 1 are installed in the mounting slots 21 of the turntable 2. A valve is installed on the outlet of the funnels 1. The outlet of the funnels 1 is 1-10 mm below the surface of the coolant liquid. In use, high-purity gallium liquid is filled into multiple funnels 11, and then the funnels 1 are fixed in the mounting slots 21 of the turntable 22. The valves of all funnels 1 can be controlled to open intermittently or to be normally open. At this time, the drive device 3 drives the turntable 2 and the funnels 1 to rotate together, so that the position of the high-purity gallium liquid dripping into the coolant changes automatically. At the same time, the conveyor 5 continuously transports gallium particles out of the cooling tank 4, separating the formed and unformed gallium particles and gallium wafers in time, avoiding accumulation and adhesion.

[0031] In this embodiment, the purity of the high-purity gallium liquid in the funnel is 5N~7N, the temperature of the high-purity gallium liquid is 40~60℃, the funnel is made of PP material, the valve is made of polytetrafluoroethylene material, the volume of the funnel is 125mL~500mL, the diameter of the funnel discharge port is 0.5~2.0mm, the turntable is made of PP plastic, and the diameter of the turntable is 300~500mm. Preferably, 4~5 mounting grooves 21 are equally spaced on a concentric circle with the center of the turntable, and the diameter of the mounting grooves 21 is 80~100mm. Preferably, the rotation speed of the turntable is 100~200 r / min, the coolant is pure water with a resistivity greater than 18 MΩ, the cooling tank is made of PP plastic and connected to a chiller with the temperature controlled at 0~10℃, the conveyor is made of polytetrafluoroethylene, the spacing between adjacent barrier bars is 150~200 mm, the barrier bars are used to prevent high-purity gallium liquid particles from rolling off, the conveyor support structure is 304 stainless steel with fluorine spraying, and the collection container is made of PP plastic. The bottom plate and side walls of the collection container are screens smaller than the size of high-purity gallium liquid particles, thus facilitating water filtration.

[0032] Example 1:

[0033] High-purity gallium liquid with a purity of 7N was heated to 50°C and poured into four 125mL funnels. The funnels were then fixed on a turntable. The coolant was pure water with a resistivity of 18.25MΩ, and the temperature was set to 5°C. The height was adjusted so that the liquid level was about 2mm above the outlet of the funnel, with an outlet diameter of 0.5mm. The funnel valves were opened, and the turntable was rotated by a drive device at a speed of 100r / min. The high-purity gallium liquid dripped into the cooling tank and onto a conveyor. The conveyor ran continuously at a speed of 0.5m / s, continuously transporting the high-purity gallium particles from the cooling tank. The particles were collected in a collection container at the end of the conveyor, rinsed with pure water, dried, and screened to remove unformed high-purity gallium particles. The qualified high-purity gallium particles were packaged and sealed. A continuous feed of 50kg yielded 46.75kg of qualified high-purity gallium particles with a diameter of approximately 2mm, resulting in a yield rate of 93.5%.

[0034] Example 2:

[0035] High-purity gallium liquid with a purity of 6N was heated to 50°C and poured into four 250mL funnels. The funnels were then fixed on a turntable. The coolant was pure water with a resistivity of 18.25MΩ, and the temperature was set to 5°C. The height was adjusted so that the liquid level was approximately 5mm above the outlet of the funnel, with an outlet diameter of 1.0mm. The funnel valves were opened, and the turntable was rotated by a drive device at a speed of 100r / min. The high-purity gallium liquid dripped into the cooling tank and onto a conveyor. The conveyor ran continuously at a speed of 0.5m / s, continuously transporting the high-purity gallium particles from the cooling tank. The particles were collected in a collection container at the end of the conveyor, rinsed with pure water, dried, and screened to remove unformed high-purity gallium particles. The qualified high-purity gallium particles were packaged and sealed. A continuous feed of 80kg yielded 73.04kg of qualified high-purity gallium particles with a diameter of approximately 5mm, resulting in a yield rate of 91.3%.

[0036] Comparative Example 1:

[0037] High-purity gallium liquid with a purity of 6N was heated to 50°C and poured into four 125mL funnels. The funnels were then fixed on a turntable. The coolant was pure water with a resistivity of 18.25MΩ, and the temperature was set to 5°C. The height was adjusted so that the liquid level was about 2mm above the outlet of the funnel, with an outlet diameter of 0.5mm. The funnel valves were opened, but the drive unit and conveyor were not started. The high-purity gallium liquid dripped into the cooling tank and accumulated on the conveyor. After feeding was complete, the conveyor was started to transport the high-purity gallium particles from the cooling tank and collect them in a collection container at the end of the conveyor. After rinsing with pure water and drying, the unformed high-purity gallium particles were screened out. The qualified high-purity gallium particles were packaged and sealed. After continuous feeding of 2.4kg, a large number of high-purity gallium particles adhered to each other, resulting in 1.59kg of qualified high-purity gallium particles with a diameter of about 2mm, with a yield rate of 66.2%.

[0038] The above are merely preferred embodiments of this utility model and do not limit the patent scope of this utility model. Any equivalent structural transformations made based on the concept of this utility model and the contents of the specification and drawings of this utility model, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this utility model.

Claims

1. A molding apparatus for high-purity gallium granules, characterized in that, The rack is provided with an upwardly open cooling tank (4) containing cooling liquid, and a conveyor (5) is obliquely arranged in the cooling tank (4) with its inlet end arranged at the bottom of the cooling tank (4) and its outlet end arranged outside the cooling tank (4), and a high-purity gallium dripping device is arranged on the rack above the inlet end of the conveyor (5) with its outlet arranged directly above the inlet end of the conveyor (5).

2. The forming apparatus for high purity gallium pellets according to claim 1, wherein: The internal depth of the cooling tank (4) is 800-1000 mm.

3. The forming apparatus for high purity gallium pellets according to claim 1, wherein: A collecting container (6) is arranged on the rack below the outlet end of the conveyor (5).

4. The apparatus according to claim 3, wherein: The bottom plate and the side wall of the collecting container (6) are both sieve nets with a mesh size smaller than that of the high-purity gallium liquid.

5. The apparatus for forming a high purity gallium pellet according to claim 1, wherein: A plurality of blocking strips (51) are fixed on the conveying belt of the conveyor (5) and arranged perpendicularly to the conveying direction of the conveying belt, and adjacent blocking strips (51) enclose storage cells arranged continuously on the conveying belt.

6. The apparatus for forming a high-purity gallium pellet according to claim 5, wherein: The distance between adjacent blocking strips (51) is 150-200 mm.

7. The apparatus according to claim 1, wherein: The cooling tank (4) is connected to a water chiller, and the temperature of the cooling water in the cooling tank (4) is 0-10℃.

8. The apparatus according to any one of claims 1 to 7, wherein: The high-purity gallium dripping device comprises a rotating disc (2) and a funnel (1) for placing high-purity gallium liquid, the rotating disc (2) is driven to rotate by a driving device (3), a plurality of mounting grooves for mounting the funnels (1) are arranged on the rotating disc (2), the funnels (1) are mounted in the mounting grooves of the rotating disc (2), and a valve is arranged on the discharge port of each funnel (1).

9. The apparatus according to claim 8, wherein: The discharge port of each funnel (1) is arranged 1-10 mm below the liquid level of the cooling liquid.

10. The apparatus according to claim 8, wherein: The rotating speed of the rotating disc (2) is 100-200 r / min.

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