Single crystal furnace

Abstract

The utility model discloses a single crystal furnace. The single crystal furnace may include: a furnace body; the heater is coaxially arranged in the furnace main body; the heat preservation structure is coaxially arranged in the furnace main body and located on the periphery of the heater, and the heat preservation structure is divided into a first heat preservation structure and a second heat preservation structure in the axial direction; the thermoelectric power generation structure is arranged between the first heat preservation structure and the second heat preservation structure and provided with a cold end, a hot end and a current leading-out structure, the cold end is located on the outer side of the heat preservation structure, the hot end is located on the inner side of the heat preservation structure, and the current leading-out structure leads out current generated by the thermoelectric power generation structure out of the furnace body. According to the single crystal furnace, part of waste heat can be recycled, and heat loss is reduced, so that the production cost of a single crystal silicon rod is reduced.

Description

Technical Field

[0001] This utility model relates to a single crystal furnace. Background Technology

[0002] When using a single-crystal furnace to pull single-crystal silicon rods, especially in the process of pulling large or ultra-large single-crystal silicon rods, a heater is generally needed to heat the crucible containing molten silicon to meet the pulling requirements. However, the single-crystal furnace cannot fully utilize the heat provided by the heater, resulting in a certain amount of energy loss. In particular, as the size of the single-crystal silicon rod increases, the energy loss will further increase, leading to higher production costs for single-crystal silicon rods. Utility Model Content

[0003] In view of this, the present invention provides a single crystal furnace that can recover and utilize part of the waste heat, reduce heat loss, and reduce the production cost of single crystal silicon rods.

[0004] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0005] This utility model embodiment provides a single crystal furnace, including:

[0006] Furnace body;

[0007] The heater is coaxially disposed inside the furnace body;

[0008] A heat insulation structure is coaxially disposed within the furnace body and located on the outer periphery of the heater. The heat insulation structure is axially divided into a first heat insulation structure and a second heat insulation structure.

[0009] A thermoelectric power generation structure is disposed between the first insulation structure and the second insulation structure, and has a cold end, a hot end and a current output structure. The cold end is located on the outside of the insulation structure, the hot end is located on the inside of the insulation structure, and the current output structure outputs the current generated by the thermoelectric power generation structure to the outside of the furnace body.

[0010] The first aspect of the above-mentioned utility model has the following advantages or beneficial effects:

[0011] The single crystal furnace provided in this embodiment of the utility model can generate electricity by using the temperature difference between the outer and inner sides of the insulation structure through a thermoelectric power generation structure set between the first insulation structure and the second insulation structure. That is, the thermoelectric power generation structure can absorb part of the heat inside the furnace body, realize the recovery and utilization of heat energy, effectively reduce the heat loss of the single crystal furnace, and reduce the production cost of single crystal silicon rods.

[0012] In addition, the thermoelectric power generation structure can absorb some of the heat inside the furnace body. After the single crystal silicon pulling is completed, it can accelerate the cooling of the single crystal furnace, shorten the cooling time of the single crystal furnace, shorten the production time interval of each single crystal silicon rod, and thus improve the production efficiency of the single crystal furnace in producing each single crystal silicon rod.

[0013] Furthermore, based on the power generation of the thermoelectric generator structure, the temperature inside the single crystal furnace can be quickly and timely obtained. The relationship between the temperature inside the single crystal furnace and temperature regulation derived from empirical data can guide precise and timely control of the temperature inside the single crystal furnace, which helps to reduce the difficulty of energy control. Attached Figure Description

[0014] Figure 1 This is a cross-sectional structural diagram of a conventional single-crystal furnace;

[0015] Figure 2 This is a cross-sectional structural schematic diagram of the first type of single crystal furnace provided according to the embodiments of this utility model;

[0016] Figure 3 This is a cross-sectional structural schematic diagram of the second type of single crystal furnace provided according to an embodiment of the present utility model;

[0017] Figure 4 This is a three-dimensional perspective view of the thermoelectric power generation structure provided according to an embodiment of the present utility model;

[0018] Figure 5 This is a top view of the thermoelectric power generation structure provided according to an embodiment of the present utility model;

[0019] Figure 6 This is a three-dimensional perspective view of the support structure provided according to an embodiment of the present utility model;

[0020] Figure 7 This is a top view of the support structure provided according to an embodiment of the present utility model.

[0021] The attached figures are labeled as follows:

[0022] 10-Furnace body; 20-Heater; 30-First insulation structure; 31-Upper insulation component; 32-Middle insulation component; 33-Lower insulation component; 40-Second insulation structure; 50-Thermoelectric power generation structure; 51-P-type doped thermoelectric component; 52-N-type doped thermoelectric component; 53-Cold end connector; 54-Hot end connector; 55-Gap; 56-First electrode connector; 57-Second electrode connector; 60-Support structure; 61-Support rod; 62-Upper annular support plate; 63-Lower annular support plate; 70-Current lead-out structure; 80-Connecting port; 90-Energy storage device; 100Insulation felt; 200-Quartz crucible. Detailed Implementation

[0023] Czochralski (Czochralski) single-crystal silicon is currently the most widely used technology for producing single-crystal silicon. The Czochralski process mainly includes: loading high-purity polycrystalline silicon into a quartz crucible, which is then heated by a heater surrounding the crucible to melt the polycrystalline silicon. A silicon single crystal with a specific crystal orientation (called a seed crystal) is then brought into contact with the molten silicon solution inside the crucible. At a suitable temperature, silicon on the surface of the molten silicon forms regular crystals at the solid-liquid interface, following the arrangement of silicon atoms on the seed crystal, thus growing into a single-crystal silicon rod. During the growth of the single-crystal silicon rod, the silicon in the molten silicon crystallizes, simultaneously lifting the seed crystal upwards. When the seed crystal grows to near the target diameter, the lifting rate is changed to ensure constant-diameter growth of the single crystal, resulting in a single-crystal silicon rod of constant diameter. After the constant-diameter growth of the single-crystal silicon rod is completed, the final stage of single-crystal silicon rod growth begins. In the final stage of single-crystal silicon rod production, by adjusting the lifting speed of the single-crystal silicon rod and the solution temperature, the diameter of the lower end of the single-crystal silicon rod is gradually reduced to form a tail-shaped cone. When the tip of the cone is small enough, the single-crystal silicon rod will separate from the melt, completing the entire process of silicon single-crystal growth.

[0024] Throughout the entire process of pulling single-crystal silicon rods, it is necessary to maintain the temperature inside the single-crystal furnace. The existing structure of a single-crystal furnace can be as follows: Figure 1 As shown. Figure 1As shown, existing single-crystal furnaces primarily insulate the quartz crucible 200 by using an insulating felt 100 installed within the furnace body 10. Specifically, for large-sized single-crystal silicon rods, the quartz crucible 200 needs to hold more molten silicon, and the heater 20 needs to provide more heat. In existing single-crystal furnaces, the heat generated by the heater is conducted directly to the molten silicon through the quartz crucible 200, and also reflected back to the thermal field where the quartz crucible 200 is located through the insulating felt 100. Because the insulating felt 100 has strong insulation properties, it results in a smaller temperature gradient in the vertical direction of the thermal field where the quartz crucible 200 is located. This smaller temperature gradient is not only detrimental to the growth of the single-crystal silicon rod, but also causes strong thermal convection in the molten silicon within the quartz crucible 200. Under this strong thermal convection, the molten silicon reacts with the quartz crucible 200, producing oxygen impurities that enter the molten silicon, resulting in a high oxygen impurity content in the single-crystal silicon rod. In particular, producing large-sized monocrystalline silicon rods requires significantly more heat, leading to increased heat loss. Furthermore, controlling the heat and vertical temperature gradient within the thermal field becomes more challenging, compromising the quality of the produced rods. Additionally, the increased heat required for large-sized rods results in substantial heat radiation within the single-crystal furnace. After the rod is drawn, a significant amount of residual heat remains, causing heat waste and requiring considerable time to dissipate. This leads to a longer interval between rod productions, ultimately reducing the efficiency of large-sized monocrystalline silicon rod production.

[0025] In order to solve the above-mentioned problems of existing single crystal furnaces, and especially to address the problems of single crystal furnaces pulling large-sized single crystal silicon rods, this utility model provides a single crystal furnace with a novel structure.

[0026] It is worth noting that the single crystal furnace provided by this invention can be used to produce single crystal silicon rods of various sizes. The single crystal furnace provided by this invention can better overcome the aforementioned problems of existing single crystal furnaces when producing large-sized single crystal silicon rods.

[0027] The specific structure of the single crystal furnace provided in this embodiment of the present invention will be described in detail below. Figure 2 and Figure 3 This is a cross-sectional structural schematic diagram of a single crystal furnace provided according to an embodiment of the present utility model; Figure 4 This is a three-dimensional perspective view of the thermoelectric power generation structure provided according to an embodiment of the present utility model; Figure 5 This is a top view of the thermoelectric power generation structure provided according to an embodiment of the present utility model; Figure 6 This is a three-dimensional perspective view of the support structure provided according to an embodiment of the present utility model; Figure 7This is a top view of the support structure provided according to an embodiment of the present utility model.

[0028] Specifically, such as Figure 2 As shown, the single crystal furnace provided in this embodiment of the present invention may include: furnace body 10, heater 20, heat preservation structure and thermoelectric power generation structure 50.

[0029] Among them, such as Figure 2 As shown, the heater 20, the insulation structure, and the thermoelectric power generation structure 50 are disposed within the furnace body 10. Specifically, the heater 20 is coaxially disposed within the furnace body 10; the insulation structure is also coaxially disposed within the furnace body 10. Coaxial disposal means that the central axis of one structure coincides with the central axis of another structure. For example, the heater 20 is disposed circumferentially along the inner wall of the furnace body 10, and the central axis of the annular structure enclosed by the heater 20 coincides with the central axis of the furnace body 10; the insulation structure is also disposed circumferentially along the inner wall of the furnace body 10, and the central axis of the annular structure of the insulation structure also coincides with the central axis of the furnace body 10. This structural arrangement ensures that the grown single-crystal silicon rod is heated evenly at the same height.

[0030] More specifically, regarding the insulation structure, it is coaxially disposed within the furnace body 10 and located on the outer periphery of the heater 20, and is divided into a first insulation structure 30 and a second insulation structure 40 in the axial direction; the thermoelectric power generation structure 50 is disposed between the first insulation structure 30 and the second insulation structure 40. For example, as... Figure 2 As shown, the first insulation structure 30 is located above the second insulation structure 40. Correspondingly, the thermoelectric power generation structure 50 is located below the first insulation structure 30, and the second insulation structure 40 is located below the thermoelectric power generation structure 50. It can be understood that the second insulation structure 40 can also be located above the first insulation structure 30, with the thermoelectric power generation structure 50 located below the second insulation structure 40, and the first insulation structure 30 located below the thermoelectric power generation structure 50. It is worth noting that the insulation structures located on the outer periphery of the heater 20 are generally as follows... Figure 2 and Figure 3 As shown, the outer wall of the quartz crucible 200 corresponds to a portion of the insulation structure to ensure that the first insulation structure 30 can effectively insulate the silicon liquid inside the quartz crucible 200. It should be noted that the thermoelectric power generation structure 50 being located below the first insulation structure 30 generally means that the thermoelectric power generation structure 50 is in direct or indirect contact with the lower part of the first insulation structure 30, and that the thermoelectric power generation structure 50 abuts against the lower part of the first insulation structure 30 or the gap between the thermoelectric power generation structure 50 and the lower part of the first insulation structure 30 is completely filled. This prevents turbulence caused by temperature differences between the thermoelectric power generation structure 50 and the lower part of the first insulation structure 30, thereby improving the thermal stability within the furnace body 10.

[0031] In addition, regarding the location of the thermoelectric power generation structure 50, it can be set between the first insulation structure 30 and the second insulation structure 40, or it can be set above the first insulation structure 30 to help cool the lower end of the monocrystalline silicon rod, increase the temperature difference in the vertical direction of the monocrystalline silicon rod, and thus increase the growth rate of the monocrystalline silicon rod.

[0032] The thermoelectric power generation structure 50 generally has a cold end, a hot end, and a current extraction structure 70. The cold end is located on the outside of the insulation structure, the hot end is located on the inside of the insulation structure, and the current extraction structure 70 extracts the current generated by the thermoelectric power generation structure 50 to the outside of the furnace body 10. The outside of the insulation structure refers to the area connecting the outer wall of the insulation structure to the inner wall of the furnace body 10; the inside of the insulation structure refers to the area enclosed by the inner wall of the insulation structure.

[0033] Among them, the thermoelectric power generation structure 50 generates current by utilizing the temperature difference between the inner and outer sides of the insulation structure in the furnace body 10.

[0034] Specifically, the thermoelectric power generation structure 50 can draw electrical energy out of the furnace body 10 by means of a current extraction structure 70, such as a current lead-out line, drawing electrical energy from the top of the furnace body 10. Alternatively, it can be implemented as follows: Figure 3 As shown, a communication port 80 is provided on the furnace body 10, through which the current extraction structure 70 extends to the outside of the furnace body 10. Exemplarily, the current extraction structure 70 is connected to the energy storage device 90 after being led to the outside. By providing a communication port on the furnace body 10 corresponding to the thermoelectric generator structure 70, the current transmission path can be reduced, thereby reducing the impact of the high-temperature environment inside the furnace body 10 on current transmission, thus improving current collection capacity and ensuring the accuracy of the temperature inside the furnace body 10 subsequently inferred based on the magnitude of the current transmitted by the current extraction structure 70, thereby improving the accuracy of temperature and energy control within the furnace body 10.

[0035] Understandably, the heater 20 described above is also used to heat the quartz crucible 200 used to hold the molten silicon. This heater can also be replaced with other heating structures such as heating coils. It is worth noting that... Figure 2 and Figure 3 The heater 20 shown is arranged around the side wall of the quartz crucible 200 as an example only. In addition to being arranged around the side wall of the quartz crucible 200, the heater 20 can also be arranged at the bottom of the quartz crucible 200 (not shown in the figure).

[0036] against Figure 2 and Figure 3The provided single crystal furnace can generate electricity by using the temperature difference between the outer and inner sides of the insulation structure through the thermoelectric power generation structure 50 set between the first insulation structure 30 and the second insulation structure 40. That is, the thermoelectric power generation structure 50 can absorb part of the heat inside the furnace body 10, realize the recovery and utilization of heat energy, effectively reduce the heat loss of the single crystal furnace, and reduce the production cost of single crystal silicon rods.

[0037] In addition, the thermoelectric power generation structure 50 can absorb some of the heat inside the furnace body 10. After the single crystal silicon pulling is completed, it can accelerate the cooling of the single crystal furnace, shorten the cooling time of the single crystal furnace, shorten the production time interval of each single crystal silicon rod, and thus improve the production efficiency of the single crystal furnace in producing each single crystal silicon rod.

[0038] Furthermore, based on the power generation of the thermoelectric generator structure, the temperature inside the single crystal furnace can be quickly and timely obtained. The relationship between the temperature inside the single crystal furnace and temperature regulation derived from empirical data can guide precise and timely control of the temperature inside the single crystal furnace, which helps to reduce the difficulty of energy control.

[0039] In addition, compared to the heat preservation structure, the thermoelectric power generation structure 50 can increase heat dissipation. Furthermore, the thermoelectric power generation structure 50 can absorb some of the heat within the furnace body 10. When the plane where the upper edge of the thermoelectric power generation structure 50 is located corresponds to or is below the bottom of the quartz crucible 200, the thermoelectric power generation structure 50 can further accelerate the cooling of the lower part of the quartz crucible 200. This effectively slows down the thermal convection of the molten silicon within the quartz crucible 200, thereby reducing the reaction between the molten silicon and the quartz crucible 200. This reduces the amount of oxygen entering the molten silicon from the reaction, thus reducing the amount of oxygen impurities introduced into the pulled single-crystal silicon rod and improving the quality of the pulled single-crystal silicon rod. Furthermore, the thermoelectric power generation structure 50, regardless of its location, can increase the longitudinal temperature gradient within the single-crystal furnace, thereby increasing the temperature gradient in the vertical direction (i.e., axial direction) of the single-crystal silicon rod. This facilitates crystallization and growth, thereby improving the growth rate and efficiency of the single-crystal silicon rod.

[0040] Regarding the relationship between the first insulation structure 30 and the second insulation structure 40 in the insulation structure, as mentioned above, it can be that the first insulation structure 30 is located above the second insulation structure 40, or the second insulation structure 40 is located above the first insulation structure 30.

[0041] For example, taking the first insulation structure 30 located above the second insulation structure 40 as an example, Figure 2 and Figure 3As shown, the upper edge of the first insulation structure 30 is higher than the upper edge of the heater 20, and the lower edge of the first insulation structure 30 is lower than the lower edge of the heater 20. By designing the relative positional relationship between the first insulation structure 30 and the heater 20, the temperature of the silicon melt in the quartz crucible 200 can be kept stable, thereby ensuring stable production of single crystal silicon rods.

[0042] The first insulation structure 30 mentioned above can be an integral structure.

[0043] Alternatively, the aforementioned first insulation structure 30 can also be a split structure. Specifically, such as... Figure 3 As shown, the first insulation structure 30 may include: an upper insulation component 31, a middle insulation component 32, and a lower insulation component 33. The upper edge of the middle insulation component 32 is flush with or exceeds the upper edge of the heater 20, and the lower edge of the middle insulation component 32 is lower than the lower edge of the heater 20. The upper insulation component 31 extends above the middle insulation component 32 and is fixed to it. The lower insulation component 33 extends below the middle insulation component 32 and is fixed to it. This separate design of the upper insulation component 31, middle insulation component 32, and lower insulation component 33 facilitates the assembly and disassembly of the first insulation structure 30.

[0044] Furthermore, such as Figure 3 As shown, the inner diameter of the upper insulation component 31 is smaller than the inner diameter of the middle insulation component 32. By reducing the inner diameter of the upper insulation component 31, the silicon melt in the quartz crucible 200 can be better insulated, and the temperature of the lower end of the single crystal silicon rod can be kept stable, thereby improving the yield of the produced single crystal silicon rods.

[0045] More preferably, the upper insulation component 31 and the middle insulation component 32 are an integral structure. Through the design of the upper insulation component 31 and the middle insulation component 32 as an integral structure, the stability of the upper insulation component 31 can be effectively improved.

[0046] Furthermore, regarding the thermoelectric power generation structure 50, such as Figure 4 and Figure 5 As shown, it may include: n P-type doped thermoelectric components 51, n N-type doped thermoelectric components 52, and multiple electrical connectors. The n P-type doped thermoelectric components 51 and n N-type doped thermoelectric components 52 are arranged alternately and at intervals to form a ring structure and are connected in series through multiple electrical connectors. The inner ends of the P-type doped thermoelectric components 51 and N-type doped thermoelectric components 52 constitute the hot end of the thermoelectric power generation structure 50, and the outer ends of the P-type doped thermoelectric components 51 and N-type doped thermoelectric components 52 constitute the cold end of the thermoelectric power generation structure 50. The thermoelectric power generation structure 50 generates electricity using the temperature difference between the cold and hot ends.

[0047] More specifically, the multiple electrical connectors include intermediate connectors and end connectors, with the intermediate connectors connecting adjacent P-type doped thermoelectric components 51 and N-type doped thermoelectric components in series, and the end connectors connected to the current lead-out structure 70.

[0048] The system includes multiple intermediate electrical connectors, including multiple cold-end connectors 53 and multiple hot-end connectors 54. The multiple cold-end connectors 53 connect the outer ends of the i-th P-type doped thermoelectric component 51 and the (i+1)-th N-type doped thermoelectric component 52 facing the outer side of the insulation structure, where 1 ≤ i < n. The multiple hot-end connectors 54 connect the inner ends of the j-th adjacent P-type doped thermoelectric component 51 and the j-th N-type doped thermoelectric component 52 facing the inner side of the insulation structure, where 1 ≤ j ≤ n. Here, i and j can have the same value. That is, the inner ends of the P-type doped thermoelectric component 51 and the N-type doped thermoelectric component 52 facing the inner side of the insulation structure are the hot ends, and the outer ends of the P-type doped thermoelectric component 51 and the N-type doped thermoelectric component 52 facing the outer side of the insulation structure are the cold ends. It is worth noting that, taking the N-type doped thermoelectric component 52 as the starting point and the P-type doped thermoelectric component 51 as the ending point, with the N-type doped thermoelectric components 52 and P-type doped thermoelectric components 51 arranged alternately, the j-th P-type doped thermoelectric component 51 and the j-th N-type doped thermoelectric component 52 are generally located adjacent to each other and connected to the same hot-end connector 54. Furthermore, the P-type doped thermoelectric components 51 and N-type doped thermoelectric components 52 are counted separately; that is, the i-th P-type doped thermoelectric component 51 is adjacent to the i-th N-type doped thermoelectric component 52 and connected to the same hot-end connector 54, and the j-th P-type doped thermoelectric component 51 is adjacent to the j-th N-type doped thermoelectric component 52 and connected to the same hot-end connector 54. The (i+1)-th P-type doped thermoelectric component 51 is separated from the i-th P-type doped thermoelectric component 51 by the (i+1)-th N-type doped thermoelectric component 52. For example, the first P-type doped thermoelectric component 51 and the first N-type doped thermoelectric component 52 are adjacent and connected to the same hot-end connector 54, and the second P-type doped thermoelectric component 51 is separated from the first P-type doped thermoelectric component 51 by a second N-type doped thermoelectric component 52. As another example, the third P-type doped thermoelectric component 51 and the fourth P-type doped thermoelectric component 51 are separated by a fourth N-type doped thermoelectric component 52. Understandably, different cold-end connectors 53 connect different P-type doped thermoelectric components 51 and different N-type doped thermoelectric components; different hot-end connectors 54 connect different P-type doped thermoelectric components 51 and different N-type doped thermoelectric components.

[0049] In other words, n P-type doped thermoelectric components 51, n N-type doped thermoelectric components 52, multiple cold-end connectors 53 and multiple hot-end connectors 54 are connected to an external energy storage device through a current lead-out structure 70 to form a closed loop.

[0050] The widths (i.e., the clockwise or counterclockwise direction of the annular structure) of the P-type doped thermoelectric component 51 and the N-type doped thermoelectric component 52 are generally 5mm to 100mm. For example, the widths of the P-type doped thermoelectric component 51 and the N-type doped thermoelectric component 52 can be 5mm, 8mm, 10mm, 15mm, 20mm, 30mm, 50mm, 70mm, 80mm, 85mm, 90mm, or 100mm, etc. Furthermore, the lengths (i.e., the radial direction of the annular structure) of the P-type doped thermoelectric component 51 and the N-type doped thermoelectric component 52 are generally 5mm to 100mm. For example, the lengths of the P-type doped thermoelectric component 51 and the N-type doped thermoelectric component 52 can be 5mm, 8mm, 10mm, 15mm, 20mm, 30mm, 50mm, 70mm, 80mm, 85mm, 90mm, or 100mm, etc. The height (i.e., the axial direction of the annular structure) of the P-type doped thermoelectric component 51 and the N-type doped thermoelectric component 52 is generally 1mm to 300mm. For example, the height of the P-type doped thermoelectric component 51 and the N-type doped thermoelectric component 52 can be 1mm, 5mm, 10mm, 30mm, 50mm, 80mm, 100mm, 120mm, 130mm, 150mm, 180mm, 200mm, 220mm, 250mm, 280mm or 300mm, etc.

[0051] It is worth noting that the cross-section of the annular structure formed by the alternating and spaced n P-type doped thermoelectric components 51 and n N-type doped thermoelectric components 52 can be circular, elliptical, triangular, quadrilateral, polygonal, or other shapes.

[0052] The P-type doped thermoelectric component 51 generally includes a P-type thermoelectric material or is a component with a specific structure formed from the P-type thermoelectric material. For example, the P-type thermoelectric material may be bismuth telluride doped with one or more impurities such as boron, aluminum, germanium, or gallium; it may also be an alloy formed with bismuth telluride and one or more impurities such as boron, aluminum, germanium, or gallium; lead telluride doped with one or more impurities such as boron, aluminum, germanium, or gallium; an alloy formed with lead telluride and one or more impurities such as boron, aluminum, germanium, or gallium; or a silicon-germanium alloy doped with one or more impurities such as boron, aluminum, germanium, or gallium.

[0053] Among them, electrical connectors can be formed by using highly conductive metals such as copper and aluminum as carriers and depositing a high-temperature resistant and anti-volatile film on the surface of the carrier.

[0054] The temperature of the area where the hot-end connector 54 is located is generally 1300℃~1400℃, while the temperature of the environment where the cold-end connector 53 and the end connector are located is generally 500℃~600℃. By coordinating multiple P-type doped thermoelectric components 51, multiple N-type doped thermoelectric components 52, multiple cold-end connectors 53, multiple hot-end connectors 54, and the end connectors, thermoelectric power generation is achieved using the Seebeck effect. This thermoelectric power generation structure 50 design can reduce the temperature of the environment below the quartz crucible 200, thereby reducing thermal convection of the molten silicon within the crucible 200, while simultaneously maintaining the temperature of the molten silicon so that it can grow stable single-crystal silicon along the single-crystal silicon rod, with a crystal orientation matching that of the seed crystal.

[0055] Specifically, regarding the structure of the thermoelectric power generation structure 50, inside the annular structure formed by n P-type doped thermoelectric components 51 and n N-type doped thermoelectric components 52 arranged alternately and at intervals, adjacent P-type doped thermoelectric components 51 and N-type doped thermoelectric components 52 are connected to the same hot-end connector 54, and the P-type doped thermoelectric components 51 and N-type doped thermoelectric components 52 connected to different hot-end connectors 54 are all different; outside the annular structure, adjacent P-type doped thermoelectric components 51 and N-type doped thermoelectric components 52 are connected to the same cold-end connector 53, and the P-type doped thermoelectric components 51 and N-type doped thermoelectric components 52 connected to different cold-end connectors 53 are all different, and the P-type doped thermoelectric components 51 and N-type doped thermoelectric components 52 connected to the same cold-end connector 53 are respectively connected to different hot-end connectors 54.

[0056] Specifically, n alternating P-type doped thermoelectric components 51 and n N-type doped thermoelectric components 52 are arranged such that adjacent P-type doped thermoelectric components 51 and N-type doped thermoelectric components 52 are connected by a hot-end connector 54 to form a basic power generation unit. Each P-type doped thermoelectric component 51 and each N-type doped thermoelectric component 52 belongs to only one basic power generation unit. Furthermore, in every two adjacent basic power generation units, the outer side of the P-type doped thermoelectric component 51 of one basic power generation unit is electrically connected to the outer side of the N-type doped thermoelectric component 52 of the other basic power generation unit via a cold-end connector 53. The N-type doped thermoelectric component 52 of one basic power generation unit connected to the P-type doped thermoelectric component 51 of another basic power generation unit belongs to a different basic power generation unit than the P-type doped thermoelectric component 51 of the other basic power generation units connected to the N-type doped thermoelectric component 52 of the first basic power generation unit.

[0057] The P-type doped thermoelectric component 51, the N-type doped thermoelectric component 52, the cold end connector 53, the hot end connector 54, and the end connector can be connected by welding.

[0058] More specifically, the inner and outer surfaces of the P-type doped thermoelectric component 51 and the N-type doped thermoelectric component 52 are both curved surfaces; the cold end connector 53 includes a curved surface that matches the outer surfaces of the P-type doped thermoelectric component 51 and the N-type doped thermoelectric component 52; the hot end connector 54 includes a curved surface that matches the inner surfaces of the P-type doped thermoelectric component 51 and the N-type doped thermoelectric component 52. By designing the inner and outer surfaces of the P-type doped thermoelectric component 51 and the N-type doped thermoelectric component 52 as curved surfaces, and by matching the curved surfaces of the cold end connector 53 and the hot end connector 54, the thermoelectric power generation structure 50 can be made relatively stable, improving the stability and reliability of the thermoelectric power generation structure 50 within the furnace body 10.

[0059] Furthermore, such as Figure 4 and Figure 5 As shown, for multiple end connectors, it may include a first electrode connector 56 and a second electrode connector 57. The first electrode connector 56 is connected to the end of the first N-type doped thermoelectric component 52 facing the outside of the insulation structure and is connected to the current lead-out structure 70; the second electrode connector 57 is connected to the end of the nth P-type doped thermoelectric component 51 facing the outside of the insulation structure and is connected to the current lead-out structure 70. Understandably, the counting method for N-type doped thermoelectric components 52 and P-type doped thermoelectric components 51 is generally based on the N-type doped thermoelectric component 52 connected to the first electrode connector 56 as the first N-type doped thermoelectric component 52. If counting is clockwise, the P-type doped thermoelectric component 51 connected to the second electrode connector 57 can be considered as the nth P-type doped thermoelectric component 51. Then, starting from the N-type doped thermoelectric component 52 connected to the first electrode connector 56, the counting of N-type doped thermoelectric components 52 and P-type doped thermoelectric components 51 is performed clockwise. If counting is counterclockwise, the P-type doped thermoelectric component 51 connected to the second electrode connector 57 can be considered as the nth P-type doped thermoelectric component 51. Then, starting from the N-type doped thermoelectric component 52 connected to the first electrode connector 56, the counting of N-type doped thermoelectric components 52 and P-type doped thermoelectric components 51 is performed counterclockwise.

[0060] Furthermore, such as Figure 6 and Figure 7As shown, the aforementioned single-crystal furnace may further include: a support structure 60, wherein the support structure is disposed between the first insulation structure 30 and the second insulation structure 40; and a thermoelectric power generation structure 50 is disposed within the support structure 60. More specifically, the support structure abuts against the first insulation structure 30 and the second insulation structure 40. For example, in a structure where the second insulation structure 40 is located below the first insulation structure 30, the upper end of the support structure 60 abuts against the lower end of the first insulation structure 30, and the lower end of the support structure 60 abuts against the upper end of the second insulation structure 40. Through this design of the support structure 60, the stability and reliability of the thermoelectric power generation structure 50 within the furnace body 10 can be further improved.

[0061] More specifically, such as Figure 6 and Figure 7 As shown, the support structure 60 may include: support rods 61 arranged at intervals to form a ring structure, an upper annular support plate 62 disposed at the upper end of the support rods 61, and a lower annular support plate 63 disposed at the lower end of the support rods 61. The support rods 61 are embedded between each pair of adjacent P-type doped thermoelectric components 51 and N-type doped thermoelectric components 52. For example, as... Figure 5 As shown, there is a gap 55 between adjacent P-type doped thermoelectric components 51 and N-type doped thermoelectric components 52, and each support rod 61 is embedded in the gap 55. Additionally, the upper annular support plate 62 abuts against the lower end of the first insulation structure 30, and the lower annular support plate 63 abuts against the upper end of the second insulation structure 40. Through the cooperation of the support rods 61 and the upper annular support plate 62 and lower annular support plate 63 located at the upper and lower ends of the support rods 61 respectively, the thermoelectric power generation structure 50 can be protected without affecting its normal operation, further improving the stability and reliability of the thermoelectric power generation structure 50 within the furnace body 10. Furthermore, the design of the upper annular support plate 62 and lower annular support plate 63 can fill the gap between the thermoelectric power generation structure 50 and the lower end of the first insulation structure 30 and the upper end of the second insulation structure 40, further improving the stability and reliability of the thermoelectric power generation structure 50.

[0062] Furthermore, the support structure 60, including the support rod 61, the upper annular support plate 62, and the lower annular support plate 63, is made of insulating material. For example, the support rod 61, the upper annular support plate 62, and the lower annular support plate 63 are made of quartz material. This support structure 60 also isolates and insulates the thermoelectric generator structure 50 from the first insulation structure 30 and the second insulation structure 40, ensuring the safety and reliability of the thermal environment within the furnace body 10.

[0063] The following explains the process and principle of pulling single-crystal silicon rods using a single-crystal furnace.

[0064] Specifically, with Figure 3Taking the single crystal furnace shown as an example, a seed crystal is introduced into the single crystal furnace. The heat generated by the heater 20 heats the silicon material in the quartz crucible 200, melting it into molten silicon. Simultaneously, the heat is reflected back into the thermal field of the single crystal furnace by the first insulation structure 30 and the second insulation structure 40. At the same time, the thermoelectric power generation structure 50 generates electricity by utilizing the temperature difference between its inner and outer sides. This electricity is then led out through the current extraction structure 70 and connected to the energy storage device 90.

[0065] Furthermore, during the single-crystal silicon rod pulling process, the presence of the thermoelectric generator structure 50 accelerates heat dissipation and increases the axial temperature gradient of the single-crystal furnace. For the quartz crucible 200, this reduces the temperature gradient in the lower region of the quartz crucible 200, thereby reducing the thermal convection of the silicon melt within the quartz crucible 200. This reduces the reaction between the silicon melt and the quartz crucible, thereby reducing oxygen impurities in the silicon melt and consequently reducing oxygen impurities in the single-crystal silicon rod, thus improving the quality of the single-crystal silicon rod. For the single-crystal silicon rod, this promotes single-crystal growth, increases the pulling rate of the single-crystal silicon rod, and thus improves the efficiency of the single-crystal silicon rod.

[0066] Furthermore, after the monocrystalline silicon rod is pulled, the thermoelectric power generation structure 50 can continue to generate electricity using the residual heat, thereby further reducing the heat loss during the monocrystalline silicon rod pulling process and accelerating the cooling of the monocrystalline furnace, reducing the heat dissipation time of the monocrystalline furnace, increasing the proportion of monocrystalline silicon rod pulling time (this proportion of monocrystalline silicon rod pulling time is equal to the monocrystalline silicon rod pulling time divided by the total usage time of the monocrystalline furnace), and increasing the yield of monocrystalline silicon rods.

[0067] Furthermore, the temperature inside the single-crystal furnace can be predicted by the power generation rate, current, or power output of the thermoelectric power generation structure 50. Based on the predicted temperature inside the furnace, the heating power of the heater 20 can be adjusted in a timely manner to regulate the temperature inside the furnace. For temperature prediction inside the single-crystal furnace, a relationship between the power generation rate, current, or power output and temperature change or temperature difference can be constructed based on the tested data, and the temperature inside the furnace can be predicted based on this relationship. For example, based on the tested power output data and temperature difference of the thermoelectric power generation structure 50, a relationship between power output and temperature difference can be constructed. Since the outer temperature of the thermoelectric power generation structure 50 is generally fixed, the inner temperature of the thermoelectric power generation structure 50 can be predicted based on the relationship between power output and temperature difference and the fixed outer temperature, so that the thermal field temperature of the single-crystal furnace can be adjusted based on the inner temperature of the thermoelectric power generation structure 50.

[0068] It is worth noting that the structure provided by this utility model is applicable to single crystal furnaces of different sizes, that is, different sizes or specifications of thermoelectric power generation structures 50 are set for single crystal furnaces of different sizes.

[0069] In addition, the thermoelectric power generation structure 50 can generate electricity during the heating stage, material preparation stage, crystal pulling stage, shoulder forming stage, equal diameter stage, finishing stage, and heat dissipation stage of the single crystal furnace, thereby improving the utilization rate of heat inside the single crystal furnace.

[0070] The above steps are provided only to help understand the method, structure, and core idea of ​​this utility model. For those skilled in the art, various improvements and modifications can be made to this utility model without departing from its principles, and these improvements and modifications also fall within the scope of protection of the claims of this utility model.

Claims

1. A single crystal furnace, characterized in that, include: Furnace body (10); The heater (20) is coaxially disposed inside the furnace body (10); The insulation structure is coaxially disposed within the furnace body (10) and located on the outer periphery of the heater (20). The insulation structure is axially divided into a first insulation structure (30) and a second insulation structure (40). Thermoelectric power generation structure (50) is located between the first insulation structure (30) and the second insulation structure (40), and has a cold end, a hot end and a current output structure (70). The cold end is located outside the insulation structure, the hot end is located inside the insulation structure, and the current output structure (70) outputs the current generated by the thermoelectric power generation structure (50) to the outside of the furnace body (10).

2. The single crystal furnace according to claim 1, characterized in that, The single crystal furnace further includes a support structure (60). The support structure (60) is disposed between the first insulation structure (30) and the second insulation structure (40), and the thermoelectric power generation structure (50) is disposed within the support structure (60).

3. The single crystal furnace according to claim 1 or 2, characterized in that, The thermoelectric power generation structure (50) includes: n P-type doped thermoelectric components (51), n ​​N-type doped thermoelectric components (52), and multiple electrical connectors, wherein the n P-type doped thermoelectric components (51) and the n N-type doped thermoelectric components (52) are arranged alternately and at intervals to form a ring structure and are connected in series through the multiple electrical connectors. The inner ends of the P-type doped thermoelectric component (51) and the N-type doped thermoelectric component (52) constitute the hot end of the thermoelectric power generation structure (50), and the outer ends of the P-type doped thermoelectric component (51) and the N-type doped thermoelectric component (52) constitute the cold end of the thermoelectric power generation structure (50).

4. The single crystal furnace according to claim 3, characterized in that, The plurality of electrical connectors include intermediate electrical connectors and end connectors, the intermediate electrical connectors being connected in series with adjacent P-type doped thermoelectric components (51) and N-type doped thermoelectric components, and the end connectors being connected to the current lead-out structure (70).

5. The single crystal furnace according to claim 4, characterized in that, The plurality of intermediate electrical connectors include a plurality of cold end connectors (53) and a plurality of hot end connectors (54). Multiple cold-end connectors (53) connect the i-th P-type doped thermoelectric component (51) to the outer end of the insulation structure and the (i+1)-th N-type doped thermoelectric component (52) to the outer end of the insulation structure, where 1 ≤ i < n; Multiple hot-end connectors (54) connect the ends of the j-th P-type doped thermoelectric assembly (51) facing the inside of the insulation structure and the ends of the j-th N-type doped thermoelectric assembly (52) facing the inside of the insulation structure, where 1≤j≤n.

6. The single crystal furnace according to claim 5, characterized in that, The multiple end connectors include a first electrode connector (56) and a second electrode connector (57). The first electrode connector (56) is connected to the end of the first N-type doped thermoelectric assembly (52) facing the outside of the insulation structure, and is also connected to the current lead-out structure (70). The second electrode connector (57) is connected to the end of the nth P-type doped thermoelectric component (51) facing the outside of the insulation structure, and is connected to the current lead-out structure (70).

7. The single crystal furnace according to claim 5 or 6, characterized in that, The inner and outer surfaces of the P-type doped thermoelectric component (51) and the inner and outer surfaces of the N-type doped thermoelectric component (52) are both curved surfaces.

8. The single crystal furnace according to claim 7, characterized in that, The cold end connector (53) and the end connector include arc surfaces that match the outer surface of the P-type doped thermoelectric assembly (51) and the outer surface of the N-type doped thermoelectric assembly (52); The hot end connector (54) includes an arc surface that matches the inner surface of the P-type doped thermoelectric assembly (51) and the inner surface of the N-type doped thermoelectric assembly (52).

9. The single crystal furnace according to claim 8, characterized in that, The single crystal furnace further includes a support structure (60). The support structure (60) includes: support rods (61) arranged at intervals to form a ring structure, and an upper annular support plate (62) at the upper end and a lower annular support plate (63) at the lower end of the support rods (61), wherein, The support rod (61) is embedded between each two adjacent P-type doped thermoelectric components (51) and N-type doped thermoelectric components (52); The upper annular support plate (62) abuts against the lower end of the first thermal insulation structure (30), and the lower annular support plate (63) abuts against the upper end of the second thermal insulation structure (40).

10. The single crystal furnace according to claim 1, characterized in that, The furnace body (10) is provided with a communication port (80), wherein, The current extraction structure (70) extends through the furnace body (10) through the communication port (80) to extract the current generated by the thermoelectric power generation structure (50) to the outside of the furnace body (10).

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