Single-crystal thermal field heat insulation ring

Abstract

The utility model relates to a single crystal thermal field heat insulation ring, which belongs to the technical field of photovoltaic manufacturing, is arranged on a heat preservation cylinder and comprises two symmetrically arranged semi-ring-shaped heat insulation ring bodies, a plurality of through holes are uniformly distributed on the heat insulation ring bodies along the semi-ring-shaped surfaces of the heat insulation ring bodies, the through holes penetrate through the heat insulation ring bodies, and the upper surfaces of the heat insulation ring bodies are obliquely arranged; the heat insulation ring is simple in structure, crystal pulling and oxygen reduction can be both achieved, the oxygen reduction effect is guaranteed, meanwhile, the unstable temperature gradient of a thermal field caused by installation of the heat insulation ring is improved, and the crystal pulling stability is guaranteed.

Description

Technical Field

[0001] The utility model relates to a heat insulation ring, in particular to a single crystal thermal field heat insulation ring, and belongs to the technical field of photovoltaic manufacturing. Background Art

[0002] A single crystal furnace is a device that uses a graphite heater to melt polycrystalline materials such as polysilicon in an inert gas (mainly nitrogen and helium) environment and grows dislocation-free single crystals using the Czochralski method. The thermal field is the thermal system in the single crystal furnace.

[0003] The insulation ring is a CC material ring set below the main heater in the single crystal furnace thermal field, which is used to reduce the heat emitted from the main heater to the bottom of the thermal field.

[0004] In recent years, an insulation ring is designed to be installed on the insulation barrel. The insulation ring uses carbon-carbon bolts to punch holes on the insulation barrel or is directly embedded between the middle and lower insulation barrels to fix the oxygen reduction ring, so as to adjust the position of the oxygen reduction ring up and down, reduce the temperature of the lower part of the crucible during the crystal pulling process, reduce the oxygen volatilization of the crucible, and reduce the oxygen content. For example, patent CN219010517U is used for an oxygen reduction device and a single crystal furnace for a single crystal furnace. The oxygen reduction device includes a mounting seat, a fixing member, and an insulation member. The mounting seat is formed into a ring shape. The insulation member extends along the extension curve of the mounting seat. The insulation member is arranged in the mounting space. By It is located between the middle insulation tube and the bottom insulation tube, which reduces the area of ​​radiation heating of the crucible by the heater, lowers the temperature of the middle and lower part of the crucible, reduces the precipitation of oxygen elements in the middle and lower part of the crucible, and thus reduces the erosion of the quartz crucible by liquid silicon at high temperature. It can effectively reduce the oxygen content in the silicon crystal and ensure the production quality of single crystal silicon. However, after the installation of this oxygen reduction device, the thermal insulation blocks the heat dissipated downward by the heater, resulting in a change in the temperature gradient of the thermal field. Although it has a good effect on oxygen reduction, it also affects the crystal pulling, increases the single crystal breakage rate, and reduces the single crystal output.

[0005] Therefore, developing a thermal insulation ring that can overcome the above defects and take into account both crystal pulling and oxygen reduction has become a technical problem that needs to be solved urgently by technical personnel in this field. Utility Model Content

[0006] The technical problem to be solved by the utility model is to overcome the shortcomings of the prior art and provide a single crystal thermal field insulation ring. The insulation ring has a simple structure and can take into account both crystal pulling and oxygen reduction, ensuring the oxygen reduction effect while improving the unstable thermal field temperature gradient caused by the installation of the insulation ring, thereby ensuring the stability of crystal pulling.

[0007] In order to solve the above technical problems, the utility model provides a single crystal thermal field insulation ring, which is arranged on a heat preservation tube, and includes two symmetrically arranged semi-annular insulation ring bodies, and a plurality of through holes are evenly distributed on the insulation ring body along its semi-annular surface. The through holes penetrate the insulation ring body, and the upper surface of the insulation ring body is inclined.

[0008] The technical solution further defined in the utility model is:

[0009] Furthermore, in the aforementioned single crystal thermal field insulation ring, the through hole is a long strip hole.

[0010] Technical effect: the long strip holes are beneficial to reducing the change of thermal field gradient and ensuring the temperature stability during the crystal pulling process.

[0011] In the above-mentioned single crystal thermal field insulation ring, the lower surface of the insulation ring body is a plane, the upper surface of the insulation ring body is inclined downward along the insulation tube wall toward the inside of the insulation tube, and the cross-section of the insulation ring body is a right-angled triangle structure.

[0012] The technical effect is that the upper surface of the insulation ring body is adjusted from a plane to an inclined surface. When the argon gas flows through the insulation ring, the argon gas is not directly blocked, but allowed to flow downward through the inclined surface, thereby weakening the insulation function of the insulation ring.

[0013] In the above-mentioned single crystal thermal field insulation ring, the angle formed by the upper surface of the insulation ring body and the bottom of the insulation ring body is 45-60°.

[0014] Technical effect: controlling the angle at 45-60° can well control the inclination of the upper surface of the insulation ring body. Too much inclination is not conducive to blocking heat, and too flat is not conducive to the circulation of argon, which will cause a large change in temperature gradient and is not conducive to the stability of crystal pulling. Controlling it at 45-60° can ensure smooth argon flow downward while blocking the heat emitted by the heater.

[0015] The aforementioned single crystal thermal field insulation ring also includes a mounting seat, which is a plurality of pins. The plurality of pins are arranged on the lower insulation tube. The pins are arranged along the circumferential direction of the lower insulation tube. One end of the pin is on the outer wall of the lower insulation tube, and the other end penetrates the lower insulation tube to form an installation space in the lower insulation tube. A corresponding insulation ring body is provided in the installation control.

[0016] Technical effect: the utility model does not use a mounting seat or other connecting fixing parts to set the insulation ring in the lower heat field. The utility model uses a simple pin to form an installation space with the lower insulation tube to set the insulation ring well on the lower insulation tube. It is easy to install and disassemble, and can be achieved by directly taking it, saving costs and improving efficiency. There are no fixing holes on the insulation ring to avoid damage to the insulation ring. At the same time, the insulation ring of the utility model is not set between the two insulation tubes, but is directly set in the lower insulation tube. It is set between the two insulation tubes, which is not very convenient to install and disassemble. If the installation is not appropriate, there will be a risk of heat leakage. The utility model is simpler and safer, and effectively improves thermal insulation and heat preservation.

[0017] The beneficial effects of the utility model are:

[0018] Existing insulation rings such asFigure 1 As shown, after installation, the heat dissipated downward by the heater is blocked by the heat insulation ring, resulting in a change in the temperature gradient of the thermal field. Although it has a good effect on oxygen reduction, it also affects crystal pulling, increases the single crystal breakage rate, and reduces the single crystal yield. Based on this phenomenon, the utility model installs a heat insulation ring on the upper part of the lower insulation barrel to reduce the temperature of the lower part of the crucible during crystal pulling, reduce the oxygen volatilization of the crucible, and achieve a reduction in oxygen content. The heat insulation ring blocks a part of the heat dissipated to the bottom by the heater, and at the same time, some heat flows downward through the through holes on the heat insulation ring body, effectively reducing the change of the heat insulation ring on the entire thermal field gradient, and ensuring the temperature stability during the crystal pulling process. In addition, the upper surface of the heat insulation ring body is adjusted from a plane to an inclined surface. When argon flows through the heat insulation ring, the argon is not directly blocked, and the argon is allowed to flow downward through the inclined surface, thereby weakening the heat insulation function of the heat insulation ring. The utility model takes into account both crystal pulling and oxygen reduction. After installation, while ensuring the oxygen reduction effect, it improves the unstable temperature gradient of the thermal field caused by the installation of the heat insulation ring, and ensures the stability of crystal pulling. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of a heat insulation ring in the prior art;

[0020] Figure 2 This is a schematic diagram of the structure of a single crystal thermal field insulation ring in an embodiment of the utility model;

[0021] Figure 3 for Figure 2 Schematic diagram of the structure of the middle insulation ring body;

[0022] In the figure: 1-insulation ring body, 2-through hole, 3-pin, 4-lower insulation cylinder. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of them; the technical features involved in the various implementation methods of the utility model described below can be combined with each other as long as they do not conflict with each other. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model. Example 1

[0024] This embodiment provides a single crystal thermal field insulation ring, the structure of which is as follows Figure 2-3As shown, it is arranged on the lower insulation cylinder, including two symmetrically arranged semi-annular insulation ring bodies 1, and a plurality of through holes 2 are evenly distributed along the semi-annular surface of the insulation ring body 1. The through holes are long strip holes, and the through holes 2 penetrate the insulation ring body 1. The lower surface of the insulation ring body 1 is a plane, and the upper surface of the insulation ring body 1 is inclined downward along the insulation cylinder wall toward the inside of the insulation cylinder. The cross-section of the insulation ring body 1 is a right-angled triangle structure, and the angle formed by the upper surface of the insulation ring body 1 and the bottom of the insulation ring body 1 is 45-60°.

[0025] The utility model also includes a mounting seat, and the thermal insulation ring is arranged in the lower insulation tube through the mounting seat. The mounting seat is a plurality of pins 3, and the plurality of pins 3 are arranged on the lower insulation tube 4. The pins 3 are arranged along the circumferential direction of the lower insulation tube 4. One end of the pin 3 is on the outer wall of the lower insulation tube 4, and the other end penetrates the lower insulation tube 4 to form an installation space in the lower insulation tube 4. A corresponding thermal insulation ring body 1 is provided in the installation space.

[0026] In this embodiment, the insulation ring and the pins are made of carbon / carbon composite materials. The characteristics of the carbon-carbon material are high temperature resistance: the carbon-carbon material can still maintain its mechanical properties at high temperatures, and the maximum operating temperature can reach 2600°C; corrosion resistance: the carbon-carbon material has good corrosion resistance and can resist the erosion of corrosive media such as acids, alkalis, and salts; good dimensional stability at high temperatures: the carbon-carbon material has good dimensional stability at high temperatures and will not deform; the use of carbon-carbon composite materials can extend the service life, reduce costs, and ensure stable operation.

[0027] In this embodiment, the part of the pin located in the lower insulation tube is not less than the width of the semi-annular insulation ring body, so that the insulation ring can be well set on the pin, stably set, and oxygen reduction can be carried out to ensure that it does not fall and does not affect the normal progress of the work. The pins are evenly distributed at the lower end of the insulation ring, wherein the two pins are ensured to be at both ends of the semi-annular insulation ring body, and a pin is also provided in the middle of the semi-annular insulation ring body. This makes it more stable when placed, disperses the force points, has stronger support and better stability, and is conducive to the insulation ring being stably set in the lower insulation tube for effective oxygen reduction without the need for fixing holes to tighten.

[0028] In addition to the above embodiments, the present invention may also have other implementations. Any technical solution formed by equivalent replacement or equivalent transformation falls within the protection scope required by the present invention.

Claims

1. A single crystal thermal field insulation ring, arranged on a heat preservation cylinder, characterized in that: It comprises two symmetrically arranged semi-annular heat-insulating ring bodies (1), a plurality of through holes (2) being evenly distributed on the heat-insulating ring body (1) along its semi-annular surface, the through holes (2) penetrating the heat-insulating ring body (1), and the upper surface of the heat-insulating ring body (1) being arranged inclined.

2. The single crystal thermal field insulation ring according to claim 1, characterized in that: The through hole (2) is a long strip-shaped hole.

3. The single crystal thermal field insulation ring according to claim 1, characterized in that: The lower surface of the insulation ring body (1) is a plane, the upper surface of the insulation ring body (1) is arranged to be inclined downward along the insulation cylinder wall toward the inside of the insulation cylinder, and the cross-section of the insulation ring body (1) is a right-angled triangle structure.

4. The single crystal thermal field insulation ring according to claim 3, characterized in that: The angle formed by the upper surface of the heat-insulating ring body (1) and the bottom of the heat-insulating ring body (1) is 45-60°.

5. The single crystal thermal field insulation ring according to claim 1, characterized in that: It also includes a mounting seat, which is a plurality of pins (3). The plurality of pins (3) are arranged on the lower insulation tube (4). The pins (3) are arranged along the circumferential direction of the lower insulation tube (4). One end of the pin (3) is on the outer wall of the lower insulation tube (4), and the other end penetrates the lower insulation tube (4) to form an installation space in the lower insulation tube (4). A matching insulation ring body (1) is provided in the installation space.

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