Heating device and crystal pulling furnace

Abstract

The embodiment of the invention provides a heating device and a crystal pulling furnace, the heating device comprises a pin, a first heating part and a second heating part, the first heating part is electrically connected with the pin, the first heating part is arc-shaped, the second heating part is electrically connected with the pin, and the second heating part is arc-shaped. Wherein the first heating part and the second heating part are arranged on the same cylindrical surface, the first heating part is located above the second heating part in the height direction of the heating device, and the projection of the first heating part and the projection of the second heating part are not completely overlapped. The first heating part and the second heating part are arc-shaped and are arranged on the same cylindrical surface, so that when the outer side wall of the crucible is heated by the first heating part and the second heating part, the outer side wall of the crucible is heated more uniformly, normal growth of crystals in the crucible is ensured, crystal defects generated in the crystal pulling process can be reduced, and the crystal pulling quality is improved. And the quality of a subsequently generated silicon wafer is improved, so that the working performance of a subsequently prepared photovoltaic cell can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of crystal pulling furnaces, and in particular to a heating device and a crystal pulling furnace. Background Art

[0002] The normal growth of single crystal silicon rods in photovoltaic crystal pulling furnaces is inseparable from the heating device. The heating device has become one of the important components of the current crystal pulling furnace. The main function of the heating device is to provide heat for the thermal field of the crystal pulling furnace, melt the initial solid raw materials into liquid and ensure the temperature gradient required for single crystal growth, maintain the normal growth of single crystals, and ensure the single crystal crystallization rate. The current heating device has the problem of uneven distribution of heating elements, which leads to uneven temperature distribution during the heating process of the single crystal silicon rod, affecting the normal growth of the single crystal silicon rod. Summary of the invention

[0003] In view of this, the embodiments of the present application provide a heating device and a crystal pulling furnace, so as to solve the technical problem of uneven temperature distribution of silicon rods during the heating process in the prior art.

[0004] In a first aspect, an embodiment of the present application provides a heating device, comprising: a pin; a first heating part, the first heating part being electrically connected to the pin, and the first heating part being arc-shaped; a second heating part, the second heating part being electrically connected to the pin, and the second heating part being arc-shaped; wherein the first heating part and the second heating part are arranged on the same cylindrical surface, and along the height direction of the heating device, the first heating part is located above the second heating part, and the projection of the first heating part does not completely overlap with the projection of the second heating part.

[0005] In the present embodiment, the first heating part and the second heating part are arc-shaped and arranged on the same cylindrical surface (that is, along the height direction of the heating device, the centers of the first heating part and the second heating part overlap, and the radii of the first heating part and the second heating part are equal. At the same time, in order to ensure that the crucible can rotate relative to the first heating part and the second heating part, a preset gap is provided between the outer wall of the crucible and the first heating part and the second heating part along the radial direction of the heating device), so that when the first heating part and the second heating part heat the outer wall of the crucible, the outer wall of the crucible is heated more evenly, thereby ensuring the normal growth of the crystal in the crucible, reducing the crystal defects generated during the crystal pulling process, improving the quality of the subsequently generated silicon wafers, and further improving the working performance of the subsequently prepared photovoltaic cells, and making the shapes of the first heating part and the second heating part more closely fit the shape of the outer wall of the crucible, thereby improving the utilization rate of the heating device.

[0006] In addition, along the height direction of the heating device, the first heating part is located above the second heating part, which can also ensure full coverage of the crucible area to be heated. At the same time, the projections of the first heating part and the second heating part are not completely overlapped. While reducing the overall power loss of the heating device, since the crucible can rotate relative to the first heating part and the second heating part, the first heating part radiates a certain amount of heat to the area not covered by the heating device, and the second heating part radiates a certain amount of heat to the area not covered by the heating device, it can also meet the heating requirements of various circumferential areas during the crystal growth process, and can meet the heating uniformity required by the crystal growth, avoiding the phenomenon of heat loss in the area not covered by the heating device.

[0007] In a specific embodiment, along the height direction of the heating device, the length H1 of the first heating portion satisfies 260 mm ≤ H1 ≤ 300 mm, and / or the length H2 of the second heating portion satisfies 280 mm ≤ H2 ≤ 340 mm.

[0008] In a specific embodiment, along the height direction of the heating device, the bottom surface of the first heating part and the top surface of the second heating part are located in the same plane.

[0009] In a specific embodiment, the central angle A1 of the first heating portion satisfies 150°≤A1≤180°, and / or the central angle A2 of the second heating portion satisfies 150°≤A2≤180°.

[0010] In a specific embodiment, the pins include two first pins and two second pins, the first pins and the second pins are used to pass current, the first heating part is electrically connected to the two first pins, and the second heating part is electrically connected to the two second pins: along the height direction of the heating device, the first pin is higher than the second pin.

[0011] In a specific embodiment, the pin also includes two pin electrodes, one of the pin electrodes is electrically connected to one of the first pins and one of the second pins, and the other of the pin electrodes is electrically connected to another of the first pins and another of the second pins, so that the first heating part and the second heating part are arranged in parallel.

[0012] In a specific embodiment, the first pin has a first step, the second pin has a second step, the first heating part has a first heating body and a first connecting part, the second heating part has a second heating body and a second connecting part, the first connecting part is installed on the first step, and the second connecting part is installed on the second step; along the circumference of the heating device, the size of the first connecting part is smaller than the size of the first step, and / or the size of the second connecting part is smaller than the size of the second step.

[0013] In the second aspect, an embodiment of the present application provides a crystal pulling furnace, which includes: a base; a crucible, which is arranged on the base; a heating device; wherein the first heating part and the second heating part are circumferentially arranged on the outside of the crucible; and the heating device is fixedly connected to the base through the pin electrode.

[0014] In a specific embodiment, along the height direction of the heating device, the top surface of the first heating part is higher than the top surface of the crucible, and the height difference L1 between the first heating part and the crucible satisfies 60mm≤L1≤70mm.

[0015] In a specific embodiment, the crystal pulling furnace further includes a control module; the control module is used to control the magnitude of the current flowing through the pin. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0017] Figure 1 A schematic structural diagram of a crystal pulling furnace provided in the present application in a specific embodiment; Figure 2 for Figure 1 A schematic diagram of the structure of the heating device; Figure 3 for Figure 2 Schematic diagram of the structure of the pin; Figure 4 for Figure 2 A schematic diagram of the structure of the first heating part and the second heating part; Figure 5 for Figure 2 Top view of the .

[0018] Reference numerals: 1-Crystal pulling furnace; 11- Heating device; 111-pin; 111a-first pin; 111b- second pin; 111c-mounting hole; 111d-First step; 111e-Second step; 111f-pin electrode; 112- first heating unit; 112a-first heating body; 112b-first connecting portion; 113- second heating unit; 113a- second heating body; 113b- second connection portion; 12- Crucible; 13- Base. DETAILED DESCRIPTION

[0019] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0020] It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0021] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0022] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0023] Photovoltaic cell power generation is a technology that uses the photoelectric conversion effect to directly convert solar cells into electrical energy. Photovoltaic cell power generation technology is fully clean, relatively extensive, and resource-sufficient. It is widely used in household photovoltaic power generation systems, industrial and commercial photovoltaic power stations, and plays an important role in long-term energy strategies. The manufacture of photovoltaic cells requires multiple process steps, among which crystal pulling is a very important link. Crystal pulling refers to the process of melting high-purity silicon rods at high temperatures and then stretching them into photovoltaic wafers. The purpose of crystal pulling is to evenly distribute impurities in the silicon rods, thereby improving the quality and purity of photovoltaic wafers. The crystal pulling process generally includes three steps: melting, stretching, and cutting.

[0024] When the direct pulling method is used, the crystal pulling process needs to be carried out in a crystal pulling furnace. During the melting step, high-purity silicon rods are placed in the crystal pulling furnace and heated by a heating device to gradually melt the silicon rods. The molten silicon liquid passes through the small holes at the bottom of the crucible in the crystal pulling furnace and gradually becomes a crystal by stretching. During the stretching process, the silicon crystals gradually become thinner, and impurities and bubbles are gradually removed from the silicon crystals. After the stretching is completed, the silicon crystals will be cut into photovoltaic silicon wafers of a certain length.

[0025] The normal growth of crystals during the crystal pulling process is inseparable from the heating device, which has become one of the important components of the current crystal pulling furnace. In the related art, the heating device usually adopts an integral flat heating plate structure, which covers the side of the crucible. Since the crucible is a cylindrical structure, the integral flat heating plate structure is unevenly distributed relative to the side wall of the crucible, resulting in uneven heating of different areas of the crystal during the heating process, affecting the quality of the subsequent silicon wafers. In addition, the utilization rate of some areas of the heating device in the related art is low during the heating process, resulting in a high overall energy consumption of the heating device, which is not conducive to energy conservation and emission reduction in the production process.

[0026] To solve the above technical problems, Figure 1 As shown, the embodiment of the present application provides a heating device 11 and a crystal pulling furnace 1 including the heating device 11, wherein the heating device 11 is used to heat a crucible 12 in the crystal pulling furnace 1. The crystal pulling furnace 1 also includes a base 13, on which the crucible 12 and the heating device 11 are both disposed, and the crucible 12 is rotatably connected to the base 13 via a crucible shaft, and the heating device 11 is fixedly connected to the base 13, so that the crucible 12 can rotate relative to the heating device 11 via the crucible shaft.

[0027] At the same time Figure 2 As shown, the heating device 11 includes a pin 111, a first heating part 112 and a second heating part 113. The first heating part 112 and the second heating part 113 are both electrically connected to the pin 111, and the first heating part 112 and the second heating part 113 are both arc-shaped. The first heating part 112 and the second heating part 113 are arranged on the same cylindrical surface. Along the height direction of the heating device 11, the first heating part 112 is located above the second heating part 113, and the projection of the first heating part 112 does not completely overlap with the projection of the second heating part 113. The first heating part 112 and the second heating part 113 are arranged on the outside of the crucible 12 along the circumferential direction, so that the crucible 12 can rotate relative to the first heating part 112 and the second heating part 113.

[0028] In this embodiment, the first heating part 112 and the second heating part 113 are arc-shaped and arranged on the same cylindrical surface (that is, along the height direction of the heating device 11, the centers of the first heating part 112 and the second heating part 113 overlap, and the radii of the first heating part 112 and the second heating part 113 are equal. At the same time, in order to ensure that the crucible 12 can rotate relative to the first heating part 112 and the second heating part 113, a preset gap is provided between the outer wall of the crucible 12 and the first heating part 112 and the second heating part 113 along the radial direction of the heating device 11), so that when the first heating part 112 and the second heating part 113 heat the outer wall of the crucible 12, the outer wall of the crucible 12 is heated more evenly, thereby ensuring the normal growth of the crystal in the crucible 12, reducing the crystal defects generated during the crystal pulling process, improving the quality of the subsequently generated silicon wafers, and further improving the working performance of the subsequently prepared photovoltaic cells, and making the shapes of the first heating part 112 and the second heating part 113 more closely fit the shape of the outer wall of the crucible 12, thereby improving the utilization rate of the heating device 11.

[0029] In addition, along the height direction of the heating device 11, the first heating part 112 is located above the second heating part 113, which can also ensure that the area to be heated of the crucible 12 is fully covered. At the same time, the projections of the first heating part 112 and the second heating part 113 are not completely overlapped, which reduces the overall power loss of the heating device 11. Since the crucible 12 can rotate relative to the first heating part 112 and the second heating part 113, a certain amount of heat is radiated to the area not covered by the heating device 11 through the first heating part 112, and a certain amount of heat is radiated to the area not covered by the heating device 11 through the second heating part 113, which can also meet the heating requirements of various circumferential areas during the crystal growth process, and can meet the heating uniformity required for crystal growth, and avoid the phenomenon of heat loss in the area not covered by the heating device 11.

[0030] In a specific embodiment, Figure 1 and Figure 2 As shown, along the height direction of the heating device 11 , the length H1 of the first heating portion 112 may satisfy 260 mm ≤ H1 ≤ 300 mm, and / or the length H2 of the second heating portion 113 may satisfy 280 mm ≤ H2 ≤ 340 mm.

[0031] In this embodiment, the first heating part 112 and the second heating part 113 can be made of graphite material. Since graphite is a good conductive material, heat can be generated by passing electricity through the graphite material. By controlling the current or voltage passed through the pin 111, the heating power (i.e., the heating temperature) of the first heating part 112 and the second heating part 113 can be accurately controlled to meet different heating requirements.

[0032] Therefore, in this embodiment, when the first heating part 112 and the second heating part 113 are made of the same material, the resistivity of the first heating part 112 and the second heating part 113 can be made the same. Therefore, it is only necessary to set the first heating part 112 and the second heating part 113 of different lengths. When the same current is passed through, the heating powers of the first heating part 112 and the second heating part 113 can be different, thereby facilitating the control of the heating powers of the first heating part 112 and the second heating part 113.

[0033] At the same time, in this embodiment, as shown in Table 1 below, when the melting step is performed in the crystal pulling process, along the height direction of the heating device 11, since the second heating part 113 is closer to the loading position at the bottom of the crucible 12 relative to the first heating part 112, the length H2 of the second heating part 113 is greater than the length H1 of the first heating part 112, so that the heating power of the second heating part 113 is greater than the heating power of the first heating part 112, which can make the crystalline silicon material at the bottom of the crucible 12 melt faster. Compared with the heating devices in the related art, when the total heating power is equal, the heating device 11 provided in the present application can shorten the melting time, thereby improving production efficiency.

[0034] Table 1

[0035] As shown in Table 2, during the crystal pulling process, when the steps of seeding, equalizing and finishing are performed, since the longitudinal temperature gradient of the crystal (i.e., along the height direction of the heating device 11) is as follows during the growth of the crystal: the farther away from the growth interface, the lower the temperature. Since the first heating part 112 is farther away from the growth interface than the second heating part 113, the length H2 of the second heating part 113 is greater than the length H1 of the first heating part 112. Even if the heating power of the second heating part 113 is greater than the heating power of the first heating part 112, the heating temperature of the heating device 11 can be more in line with the temperature gradient required in the crystal growth process. Compared with the heating devices in the related art, the heating device 11 provided in the present application reduces the power required to reach the standard pulling speed during the seeding, equalizing and finishing steps, thereby improving production efficiency, reducing costs, and achieving the effect of energy conservation and emission reduction.

[0036] Table 2

[0037] In addition, along the height direction of the heating device 11, the length H1 of the first heating part 112 satisfies 260mm≤H1≤300mm, and / or the length H2 of the second heating part 113 satisfies 280mm≤H2≤340mm, even if there is a length difference between the second heating part 113 and the first heating part 112, so that when the same current is passed, the heating power of the first heating part 112 and the second heating part 113 can be different, so as to achieve a temperature gradient between the first heating part 112 and the second heating part 113. At the same time, the temperature gradient between the first heating part 112 and the second heating part 113 should not be too large or too small. When it is too large, new irregular crystal nuclei may be generated during the crystal growth process, causing the single crystal to become polycrystalline, affecting the normal growth of the crystal. When it is too small, the latent heat of crystallization generated by crystal growth cannot be dissipated in time, affecting the normal growth of the crystal. Therefore, the length H1 of the first heating part 112 satisfies 260mm≤H1≤300mm, and / or the length H2 of the second heating part 113 satisfies 280mm≤H2≤320mm, which can effectively improve production efficiency and reduce power loss while ensuring normal growth of crystals.

[0038] Among them, in the embodiment of the present application, the length H1 of the first heating part 112 and the length H2 of the second heating part 113 are not specifically limited, and the length H2 of the second heating part 113 is greater than the length H1 of the first heating part 112 by 20mm-40mm. For example, the length H1 of the first heating part 112 can be 260mm, and the length H2 of the second heating part 113 can be 280mm, or the length of the first heating part 112 can be 280mm, and the length H2 of the second heating part 113 can be 300mm, or the length of the first heating part 112 can be 300mm, and the length of the second heating part 113 can be 320mm. The specific lengths of the first heating part 112 and the second heating part 113 can also be adaptively adjusted according to the crucibles 12 of different lengths.

[0039] In a specific embodiment, Figure 1 and Figure 2 As shown, along the height direction of the heating device 1 , the bottom surface of the first heating portion 112 and the top surface of the second heating portion 113 are located in the same plane.

[0040] In this embodiment, along the height direction of the heating device 11, the bottom surface of the first heating part 112 and the top surface of the second heating part 113 are located in the same plane, so that there is no gap between the first heating part 112 and the second heating part 113 along the height direction of the heating device 11, which can improve the heating effect of the first heating part 112 and the second heating part 113 and make them completely cover the area to be heated, thereby avoiding heat loss in the area to be heated and affecting the normal growth of the crystal.

[0041] In a specific embodiment, Figure 2 , Figure 3 and Figure 5 As shown, the central angle A1 of the first heating portion 112 may satisfy 150°≤A1≤180°, and / or the central angle A2 of the second heating portion 113 may satisfy 150°≤A2≤180°.

[0042] In this embodiment, the center angle A1 of the first heating part 112 satisfies 150°≤A1≤180°, that is, the center angle A1 of the first heating part 112 should not be too large or too small. When it is too large, the area of ​​the outer wall of the crucible 12 covered by the first heating part 112 in the circumferential direction is too large, resulting in large power loss. When it is too small, the area of ​​the outer wall of the crucible 12 covered by the first heating part 112 in the circumferential direction is too small, affecting the heating effect of the first heating part 112 during the crystal pulling process. And the center angle A2 of the second heating part 113 satisfies 150°≤A2≤180°, that is, the center angle A2 of the second heating part 113 should not be too large or too small. When it is too large, the area of ​​the outer wall of the crucible 12 covered circumferentially by the second heating part 113 is too large, resulting in a large power loss. When it is too small, the area of ​​the outer wall of the crucible 12 covered circumferentially by the second heating part 113 is too small, affecting the heating effect of the second heating part 113 during the crystal pulling process.

[0043] Therefore, the central angle A1 of the first heating portion 112 satisfies 150°≤A1≤180°, and the central angle A2 of the second heating portion 113 satisfies 150°≤A2≤180°, while ensuring the heating effect of the heating device 11, it is also possible to avoid excessive power loss, thereby improving the utilization rate of the heating device 11. The central angle A1 of the first heating portion 112 can be 150°, 160°, 170°, 180°, etc., and the central angle A2 of the second heating portion 113 can be 150°, 160°, 170°, 180°, etc.

[0044] In a specific embodiment, Figure 3 and Figure 4 As shown, the pin 111 may include two first pins 111a and two second pins 111b, the first pin 111a and the second pin 111b are used to pass current, the first heating part 112 is electrically connected to the two first pins 111a, and the second heating part 113 is electrically connected to the two second pins 111b. Along the height direction of the heating device 11, the first pin 111a is higher than the second pin 111b.

[0045] In this embodiment, along the height direction of the heating device 11, the first pin 111a is higher than the second pin 111b, so that the first heating part 112 connected to the first pin 111a is higher than the second heating part 113 connected to the second pin 111b, so that the first heating part 112 and the second heating part 113 have a height difference, so that the first heating part 112 and the second heating part 113 can heat different areas to meet the temperature gradient required during the crystal growth process.

[0046] In a specific embodiment, Figure 3 and Figure 4 As shown, the pin 111 may also include two pin electrodes 111f, one pin electrode 111f is electrically connected to a first pin 111a and a second pin 111b, and the other pin electrode 111f is electrically connected to another first pin 111a and another second pin 111b, so that the first heating part 112 and the second heating part 113 are arranged in parallel.

[0047] In this embodiment, the pin 111 includes a pin electrode 111f for connecting to an external power source, so that current can flow through the pin 111 to the first heating part 112 and the second heating part 113 respectively, and the pin electrode 111f is electrically connected to the first pin 111a and the second pin 111b respectively, so that the power supply circuit of the first heating part 112 and the power supply circuit of the second heating part 113 can be connected in parallel, and then the currents flowing through the first heating part 112 and the second heating part 113 are equal, so that different heating powers can be achieved by setting the first heating part 112 and the second heating part 113 of different lengths, which facilitates the adjustment of the heating temperature of different areas to meet the temperature gradient during the crystal growth process.

[0048] In another specific embodiment, when there is a gap between the two ends of the first heating part and the two ends of the second heating part along the circumference of the heating device (not shown in the figure), two pin electrodes can be separately provided on the two first pins of the first heating part, and two pin electrodes can also be separately provided on the two second pins of the second heating part.

[0049] In a specific embodiment, Figure 3 and Figure 4As shown, the first pin 111a has a first step 111d, the second pin 111b has a second step 111e, the first heating part 112 has a first heating body 112a and a first connecting part 112b, the second heating part 113 has a second heating body 113a and a second connecting part 113b, the first connecting part 112b is installed on the first step 111d, and the second connecting part 113b is installed on the second step 111e, along the circumference of the heating device 11, the size of the first connecting part 112b is smaller than the size of the first step 111d, and / or the size of the second connecting part 113b is smaller than the size of the second step 111e.

[0050] In this embodiment, along the circumference of the heating device 11, the size of the first connection portion 112b is smaller than the size of the first step 111d, which can improve the stability of the first connection portion 112b when installed on the first step 111d, and can avoid interference with the second heating portion 113 during the installation process, thereby reducing the difficulty of installation. And the size of the second connection portion 113b is smaller than the size of the second step 111e, which can improve the stability of the second connection portion 113b when installed on the second step 111e, and can avoid interference with the first heating portion 112 during the installation process, thereby reducing the difficulty of installation.

[0051] In a specific embodiment, Figure 1 and Figure 4 As shown, the heating device 11 can be fixedly connected to the base 13 via the pin electrode 111f.

[0052] In this embodiment, the heating device 11 is fixedly connected to the base 13 through the pin electrode 111f, which can improve the connection reliability between the heating device 11 and the base 13 and facilitate the connection of the pin electrode 111f to an external power source, thereby supplying power to the first heating part 112 and the second heating part 113.

[0053] The pin electrode 111f may also be provided with a mounting hole 111c for being screwed or clamped to the base 13, which has the advantages of simple structure and easy implementation.

[0054] In a specific embodiment, Figure 1 and Figure 2 As shown, along the height direction of the heating device 11, the top surface of the first heating part 112 may be higher than the top surface of the crucible 12, and the height difference L1 between the first heating part 112 and the crucible 12 satisfies 60mm≤L1≤70mm.

[0055] In this embodiment, the height difference L1 between the first heating part 112 and the crucible 12 satisfies 60mm≤L1≤70mm, so that the first heating part 112 and the second heating part 113 can completely cover the heating area required in the crystal growth process to meet the use requirements of crystal growth. And avoid the problem that the first heating part 112 is too long, resulting in low utilization rate of part of the first heating part 112 and increasing the overall energy consumption of the heating device 11. Among them, the height difference L1 between the first heating part 112 and the crucible 12 can be 60mm, 65mm, 70mm, etc.

[0056] In the above embodiments, the crystal pulling furnace 1 may further include a control module, and the control module is used to control the magnitude of the current flowing through the pin 111 .

[0057] In this embodiment, as shown in Table 1 and Table 2, in the stages of melting, seeding, equal diameter and finishing, the heating powers required by the first heating part 112 and the second heating part 113 are different. By setting up a control module, it is possible to automatically detect the current stage of the crystal growth process and control the current flowing to the pin 111 to adjust the heating power of the first heating part 112 and the second heating part 113 to meet the heating power required in the current stage. While playing the heating power detection function, it can also simplify the operating steps of the operator and improve production efficiency.

[0058] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A heating device, characterized in that: The heating device (11) comprises: pin(111); a first heating portion (112), the first heating portion (112) being electrically connected to the pin (111), and the first heating portion (112) being arc-shaped; a second heating portion (113), the second heating portion (113) being electrically connected to the pin (111), and the second heating portion (113) being arc-shaped; The first heating portion (112) and the second heating portion (113) are arranged on the same cylindrical surface; along the height direction of the heating device (11), the first heating portion (112) is located above the second heating portion (113), and the projection of the first heating portion (112) does not completely overlap with the projection of the second heating portion (113).

2. The heating device according to claim 1, characterized in that Along the height direction of the heating device (11), the length H1 of the first heating portion (112) satisfies 260 mm ≤ H1 ≤ 300 mm, and / or the length H2 of the second heating portion (113) satisfies 280 mm ≤ H2 ≤ 340 mm.

3. The heating device according to claim 1, characterized in that: Along the height direction of the heating device (11), the bottom surface of the first heating part (112) and the top surface of the second heating part (113) are located in the same plane.

4. The heating device according to claim 1, characterized in that A central angle A1 of the first heating portion (112) satisfies 150°≤A1≤180°, and / or a central angle A2 of the second heating portion (113) satisfies 150°≤A2≤180°.

5. The heating device according to claim 1, characterized in that: The pins (111) comprise two first pins (111a) and two second pins (111b), the first pins (111a) and the second pins (111b) being used to pass current, the first heating portion (112) being electrically connected to the two first pins (111a), and the second heating portion (113) being electrically connected to the two second pins (111b); Along the height direction of the heating device (11), the first pin (111a) is higher than the second pin (111b).

6. The heating device according to claim 5, characterized in that: The pin (111) further comprises two pin electrodes (111f), one of the pin electrodes (111f) being electrically connected to one of the first pins (111a) and one of the second pins (111b), and the other of the pin electrodes (111f) being electrically connected to another of the first pins (111a) and another of the second pins (111b), so that the first heating portion (112) and the second heating portion (113) are arranged in parallel.

7. The heating device according to claim 6, characterized in that The first pin (111a) has a first step (111d), the second pin (111b) has a second step (111e), the first heating portion (112) has a first heating body (112a) and a first connecting portion (112b), the second heating portion (113) has a second heating body (113a) and a second connecting portion (113b), the first connecting portion (112b) is mounted on the first step (111d), and the second connecting portion (113b) is mounted on the second step (111e); Along the circumference of the heating device (11), the size of the first connecting portion (112b) is smaller than the size of the first step (111d), and / or the size of the second connecting portion (113b) is smaller than the size of the second step (111e).

8. A crystal pulling furnace, characterized in that: The crystal pulling furnace (1) comprises: Base (13); A crucible (12), wherein the crucible (12) is arranged on the base (13); A heating device (11), wherein the heating device (11) is the heating device (11) according to any one of claims 1 to 7; The first heating part (112) and the second heating part (113) are arranged circumferentially outside the crucible (12); and the heating device (11) is fixedly connected to the base (13) via the pin electrode (111f).

9. The crystal pulling furnace according to claim 8, characterized in that: Along the height direction of the heating device (11), the top surface of the first heating part (112) is higher than the top surface of the crucible (12), and the height difference L1 between the first heating part (112) and the crucible (12) satisfies 60mm≤L1≤70mm.

10. The crystal pulling furnace according to claim 8, characterized in that: The crystal pulling furnace (1) further comprises a control module; The control module is used to control the magnitude of the current flowing through the pin (111).

Images