Monocrystalline silicon growth furnace and control method thereof

Abstract

The invention provides a monocrystalline silicon growth furnace and a control method thereof, and the monocrystalline silicon growth furnace comprises a crucible; the first heater is arranged on the crucible in a sleeving manner; the second heater is arranged on the first heater in a sleeving manner, a gap is formed between the second heater and the first heater, and the second heater is arranged in a deformable manner; and the adjusting assembly is arranged between the first heater and the second heater, the adjusting assembly is connected with the first heater and the second heater, and at least part of the adjusting assembly is movably arranged to drive the first heater and / or the second heater to move so as to adjust the distance between the first heater and the second heater. The problem that in the prior art, the growth quality of a single crystal silicon rod is low is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of single crystal rod production, and in particular to a single crystal silicon growth furnace and a control method thereof. Background Art

[0002] Monocrystalline silicon is a key material for manufacturing solar panels, semiconductor devices and integrated circuits. High-quality monocrystalline silicon rods are the key to monocrystalline silicon growth technology. In the traditional monocrystalline silicon rod growth process, the heater is always maintained at a high temperature, but the low temperature area uses a lower temperature, resulting in uneven temperature distribution inside the heater, causing waste of raw materials, energy loss, large temperature fluctuations, and affecting product quality.

[0003] In addition, the main heater of the existing heater often uses 105kw melt for 5-7 hours. The outer wall of the crucible is baked at high temperature for a long time, which causes a large amount of oxygen to enter the molten silicon. The oxygen content of the produced crystal rod increases, and the crystal rod oxygen high scrap phenomenon occurs from time to time, affecting the growth quality and efficiency of single crystal silicon rods. Summary of the invention

[0004] The main purpose of the present invention is to provide a single crystal silicon growth furnace and a control method thereof to solve the problem of low growth quality of single crystal silicon rods in the prior art.

[0005] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, a single crystal silicon growth furnace is provided, comprising: a crucible; a first heater, which is mounted on the crucible; a second heater, which is mounted on the first heater and is spaced apart from the first heater, and the second heater is deformably arranged; an adjusting component, which is arranged between the first heater and the second heater, the adjusting component is connected to the first heater and the second heater respectively, and at least a part of the adjusting component is movably arranged to drive the first heater and / or the second heater to move, thereby adjusting the distance between the first heater and the second heater.

[0006] Furthermore, the first heater includes: a first heating body, which is a tubular structure, and is sleeved on the outside of the crucible. Along the axial direction of the first heating body, the first heating body includes a first end face and a second end face that are oppositely arranged; a first support leg, which is arranged on the second end face and is electrically connected to the first heating body, and there are at least two first support legs, and at least two first support legs are spaced apart along the circumferential direction of the first heating body, and each first support leg is respectively connected to a power source to supply power to the first heating body.

[0007] Furthermore, the second heater includes: a second heating body, which is a tubular structure, and is sleeved on the outside of the first heating body. Along the axial direction of the second heating body, the second heating body includes a third end face and a fourth end face that are relatively arranged; a second support leg, which is arranged on the fourth end face and is electrically connected to the second heating body, and there are at least two second support legs, and at least two second support legs are arranged at intervals along the circumference of the second heating body, and each second support leg is respectively connected to a power source to supply power to the second heating body; wherein the first end face and the third end face are arranged flush.

[0008] Further, taking the axial direction of the second heating body as the height direction, the height of the second heating body is 150 mm to 200 mm; and / or,

[0009] The height of the first heating body is greater than that of the second heating body, and the distance between the second end surface and the fourth end surface is 80 mm to 180 mm.

[0010] Furthermore, a temperature detection component is provided in the crucible, and the adjustment component includes: a telescopic component, which is telescopically arranged, and the two ends of the telescopic component are respectively connected to the first heater and the second heater; a driving component, which is connected to the telescopic component for driving, and the driving component is signal-connected to the temperature detection component, and the driving component controls the telescopic displacement of the telescopic component according to the temperature information of the temperature detection component.

[0011] Furthermore, the interval between the first heater and the second heater is greater than 18 mm.

[0012] According to another aspect of the present invention, a control method for a single crystal silicon growth furnace is provided, which is applicable to the above-mentioned single crystal silicon growth furnace, and the control method includes: in the melting stage, controlling the first heater to operate for a first predetermined period of time, and then controlling the second heater to operate; after the material is melted, controlling the first heater to operate at a first power threshold, and controlling the second heater to operate at a second power threshold, the first power threshold being less than the second power threshold; thereafter, controlling the second heater to move in a direction away from the first heater.

[0013] Further, in the melting stage, the first predetermined time period is 1 hour to 3 hours; and / or the operating power of the first heater is 50% to 70% of the operating power of the second heater.

[0014] Further, after the first heater operates for a first predetermined time period, the power of the first heater is reduced to a first power threshold;

[0015] The first power threshold is 30% to 50% of the maximum power of the first heater.

[0016] Further, in the process of reducing the power of the first heater to the first power threshold, the operating power of the second heater is controlled to gradually increase to the second power threshold at a predetermined rate.

[0017] According to the technical solution of the present invention, a single crystal silicon growth furnace includes a crucible, a first heater, a second heater and an adjustment component. The first heater is sleeved on the crucible, the second heater is sleeved on the first heater, and a gap is set between the first heater and the second heater. The second heater is deformably arranged, and the adjustment component is arranged between the first heater and the second heater. The adjustment component is connected to the first heater and the second heater respectively, and at least part of the adjustment component is movably arranged to drive the first heater and / or the second heater to move, thereby adjusting the distance between the first heater and the second heater. Such an arrangement can heat the crucible by the first heater and the second heater at the same time, or heat the crucible by the first heater or the second heater alone. Combined with adjusting the distance between the two layers of heaters, the temperature gradient in the growth furnace can be accurately controlled, and by dynamically adjusting the heating power of the first heater and the second heater, the time that the outer wall of the crucible is subjected to high temperature baking for a long time is reduced, thereby reducing the oxygen content in the grown single crystal silicon rod and improving the production quality of the single crystal silicon rod. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0019] Figure 1 A schematic structural diagram of a single crystal silicon growth furnace according to the present invention is shown;

[0020] Figure 2 It shows a structural schematic diagram of the first viewing angle of the cooperation between the first heater and the second heater in the single crystal silicon growth furnace according to the present invention;

[0021] Figure 3 A schematic structural diagram of the cooperation between the first heater and the second heater in the single crystal silicon growth furnace according to the present invention from a second viewing angle is shown;

[0022] Figure 4 A top view of a first embodiment of a second heater in a single crystal silicon growth furnace according to the present invention is shown;

[0023] Figure 5 A schematic structural diagram of a second embodiment of a second heater in a single crystal silicon growth furnace according to the present invention is shown.

[0024] The above drawings include the following reference numerals:

[0025] 100, first heater; 110, first heating body; 111, first end surface; 112, second end surface; 120, first support leg; 200, second heater; 210, second heating body; 211, third end surface; 212, fourth end surface; 213, heating plate; 220, second support leg;

[0026] 300, adjustment component; 310, telescopic component;

[0027] 400. Furnace body; 410. Crucible. DETAILED DESCRIPTION

[0028] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0029] As mentioned in the background technology, the existing single crystal silicon growth furnace is usually heated by a heater. The existing heater has a high power. The outer wall of the crucible is baked at high temperature for a long time, so that a large amount of oxygen enters the molten silicon, and the oxygen content of the produced crystal rod increases, thereby affecting the quality of the product. Therefore, in view of the above technical problems, in the single crystal silicon growth furnace of the present application, a first heater 100 and a second heater 200 are arranged, and the first heater 100 and the second heater 200 are sequentially sleeved on the outside of the crucible. The crucible is heated by the first heater 100 or the second heater 200 alone, or the first heater 100 and the second heater 200 are operated simultaneously to heat the crucible. In order to meet the growth requirements of the single crystal silicon in the crucible at different stages, an adjustment component is arranged between the first heater 100 and the second heater 200, and at least part of the adjustment component is movably arranged, so as to adjust the distance between the first heater 100 and the second heater 200, which can significantly reduce the long-term high-temperature baking of the outer wall of the crucible, thereby effectively reducing the oxygen content in the growing single crystal silicon rod.

[0030] Please refer to Figures 1 to 5 The present application provides a single crystal silicon growth furnace, comprising: a crucible; a first heater 100, which is sleeved on the crucible; a second heater 200, which is sleeved on the first heater 100 and is spaced apart from the first heater 100, and the second heater 200 is deformably arranged; an adjustment component 300, which is arranged between the first heater 100 and the second heater 200, and the adjustment component 300 is respectively connected to the first heater 100 and the second heater 200, and at least a part of the adjustment component 300 is movably arranged to drive the first heater 100 and / or the second heater 200 to move, thereby adjusting the distance between the first heater 100 and the second heater 200.

[0031] According to the single crystal silicon growth furnace provided in the present application, it includes a crucible, a first heater 100, a second heater 200 and an adjustment component 300. The first heater 100 is sleeved on the crucible, the second heater 200 is sleeved on the first heater 100, and a gap is set between the first heater 100, the second heater 200 is deformably set, the adjustment component 300 is set between the first heater 100 and the second heater 200, the adjustment component 300 is respectively connected to the first heater 100 and the second heater 200, and at least a part of the adjustment component 300 is movably set to drive the first heater 100 and / or the second heater 200 to move, thereby adjusting the distance between the first heater 100 and the second heater 200. This arrangement can heat the crucible simultaneously through the first heater 100 and the second heater 200, or heat the crucible through the first heater 100 or the second heater 200 alone. Combined with adjusting the distance between the two layers of heaters, the temperature gradient in the growth furnace can be accurately controlled, and by dynamically adjusting the heating power of the first heater 100 and the second heater 200, the time that the outer wall of the crucible is subjected to high-temperature baking for a long time can be reduced, thereby reducing the oxygen content in the grown single crystal silicon rod and improving the production quality of the single crystal silicon rod.

[0032] Specifically, the first heater 100 includes: a first heating body 110, which is a tubular structure, and the first heating body 110 is sleeved on the outside of the crucible. Along the axial direction of the first heating body 110, the first heating body 110 includes a first end face 111 and a second end face 112 that are oppositely arranged; a first support leg 120, which is arranged on the second end face 112 and is electrically connected to the first heating body 110, and there are at least two first support legs 120, and at least two first support legs 120 are spaced apart along the circumferential direction of the first heating body 110, and each first support leg 120 is respectively connected to a power source to supply power to the first heating body 110. The cylindrical structure can ensure that heat is evenly distributed around the crucible, forming a uniform heating area and avoiding the problem of local overheating or insufficient heating. By arranging at least two first legs 120 on the second end surface 112 of the first heating body 110, each leg is independently connected to a power source. This multi-point power supply design can make the current distribution more uniform, reduce local current density, thereby reducing heat loss caused by current concentration, and ultimately reducing overall power consumption.

[0033] Further, the second heater 200 includes: a second heating body 210, which is a cylindrical structure, and is sleeved on the outer side of the first heating body 110. Along the axial direction of the second heating body 210, the second heating body 210 includes a third end face 211 and a fourth end face 212 that are arranged opposite to each other; a second leg 220, which is arranged on the fourth end face 212 and is electrically connected to the second heating body 210, and there are at least two second legs 220, and at least two second legs 220 are arranged at intervals along the circumference of the second heating body 210, and each second leg 220 is connected to a power source to supply power to the second heating body 210; wherein the first end face 111 and the third end face 211 are arranged flush. The cylindrical structure design of the second heating body 210 can evenly surround the first heating body 110, thereby providing a more uniform heat distribution for the growth furnace. Through the arrangement of the second leg 220, the second heater 200 can accurately adjust the power input as needed at different stages of growth. After the melting stage, by starting the second heater 200 , the heating load of the first heater 100 can be shared, thereby reducing the power requirement of the first heater 100 .

[0034] The first end surface 111 and the third end surface 211 are arranged flush with each other, which ensures that the two heaters are aligned in the axial direction, and this helps to maintain the stability of the thermal field when the distance between the heaters is adjusted.

[0035] In the present application, the height direction is the axial direction of the second heating body 210, and the height of the second heating body 210 is 150mm-200mm; and / or, the height of the first heating body 110 is greater than the height of the second heating body 210, and the distance between the second end face 112 and the fourth end face 212 is 80mm-180mm. The height of the second heating body 210 is set to 150mm-200mm, and the setting of this size range is based on the consideration of optimizing heat transfer efficiency and thermal field uniformity. The shorter height can reduce the unnecessary loss of heat, while the longer height can provide a more stable thermal field environment, ensure that the temperature gradient in the growth area is more uniform, and is conducive to the high-quality growth of single crystal silicon; the difference in height design between the first heating body 110 and the second heating body 210 enables the first heating body 110 to cover a larger range of crucibles and provide basic heating, while the second heating body 210 provides supplementary or regulated heating in the key growth stage. This complementary heating strategy can better control the temperature change during the growth process, reduce thermal field fluctuations, and improve production stability. The distance between the second heating body 210 and the first heating body 110 is set to 80 mm to 180 mm. This design has a direct positive impact on controlling the oxygen content inside the crystal during the growth of single crystal silicon. The appropriate distance can avoid excessive baking of the crucible wall by local high temperature, thereby reducing the chance of oxygen entering the molten silicon through the crucible wall, reducing the oxygen content in the single crystal silicon rod, and improving the purity of the crystal.

[0036] A temperature detection component is provided in the crucible, and the adjustment component 300 includes: a telescopic component 310, which is telescopically arranged, and the two ends of the telescopic component 310 are respectively connected to the first heater 100 and the second heater 200; a driving component, which is connected to the telescopic component 310 by driving, and the driving component is connected to the temperature detection component by signal, and the driving component controls the telescopic displacement of the telescopic component 310 according to the temperature information of the temperature detection component. The driving component is connected to the temperature detection component by signal, and can automatically adjust the telescopic displacement of the telescopic component 310 according to the received temperature information, thereby dynamically adjusting the distance between the first heater 100 and the second heater 200. This adaptive control strategy ensures the precise control of the temperature during the growth process and improves the consistency and repeatability of the crystal growth. During the adjustment process, the first heater 100 is fixed and the second heater 200 is deformably arranged.

[0037] Optionally, the telescopic component 310 is made of graphite or ceramic, and is an electric telescopic rod driven by a servo motor or a stepper motor, and the telescopic length can be accurately adjusted according to a control signal. The electric telescopic rod is usually equipped with an encoder or a displacement sensor, which can realize closed-loop control of the position, and is suitable for applications with high requirements for the accuracy of heater spacing adjustment.

[0038] Through the telescopic displacement of the telescopic component 310, the adjustment component 300 can automatically adjust the distance between the heaters at different stages of growth to optimize the distribution of the thermal field. For example, in the melting stage, the distance between the heaters can be set smaller to quickly reach a high temperature; while in the crystal growth stage, the distance between the heaters can be gradually increased to reduce the high temperature baking of the outer wall of the crucible and reduce the oxygen content in the crystal. This dynamic thermal field optimization capability significantly improves the flexibility and adaptability of the equipment.

[0039] The adaptive control function of the adjustment component 300 can adjust the working state of the heater according to the actual temperature demand, avoiding overheating or insufficient temperature, thereby reducing power consumption and improving energy efficiency. During the growth process, through intelligent adjustment of the heater layout, more efficient use of heat can be achieved, further improving production efficiency. The combination of the telescopic component 310 and the drive component makes the distance adjustment between the heaters automatic and convenient, without the need for frequent manual intervention, reducing the workload of operators. At the same time, the design of this adjustment mechanism is relatively independent, which is convenient for maintenance and troubleshooting, reducing the complexity and cost of equipment maintenance.

[0040] Specifically, in one embodiment of the present application, Figure 3 and Figure 4 As shown, the second heating body 210 includes a plurality of heating plates 213, and the plurality of heating plates 213 are connected end to end in sequence along the circumference of the second heating body 210, and a preset gap is arranged between two adjacent heating plates 213, wherein the preset gap can provide a deformation space for the second heating body 210, and when the telescopic component 310 is extended, the second heating body 210 is expanded, and the preset gap becomes larger, thereby increasing the distance between the second heating body 110 and the first heating body 110. Optionally, a plurality of telescopic components 310 are arranged, and the plurality of telescopic components 310 are evenly arranged along the circumference of the second heating body 210 to provide uniform thrust to the second heating body 210, which is beneficial to the uniform heating of the crucible by the second heating body 210 during operation. Limited by the space in the furnace body and the structural strength of the second heating body 210, that is, the diameter of the second heating body 210 in the initial state is D, the maximum diameter of the second heating body 210 after deformation is D2, and the difference between D2 and D is 0.8mm~20mm. In this way, the power control of the second heating body 210 and the first heating body 110 is coordinated to achieve effective utilization of heat, which helps to reduce power consumption while reducing the oxygen content in the crystal.

[0041] In another embodiment of the present application, Figure 5As shown, the second heating body 210 includes a plurality of heating plates 213, each of which is an arc-shaped plate. Each of the heating plates 213 is arranged around the crucible 410 to heat the crucible respectively. There are multiple telescopic parts 310, and the multiple telescopic parts 310 are arranged one by one with the multiple heating plates 213. When the second heating body 210 is in the initial position, the two adjacent heating plates 213 fit each other to form a complete heating body. At this time, the heating area of ​​the heater is the largest and the thermal field distribution is the most concentrated. The telescopic parts 310 are in a contracted state, and the connection with the heating plates 213 is tight. When the distance between the first heating body 110 and the second heating body 210 needs to be adjusted, the control system sends a command to each telescopic part 310 so that they extend at a predetermined rate at the same time. As the telescopic parts 310 are extended, the heating plates 213 are gradually pushed away, the overall shape of the heating body changes, and the heating area is expanded, thereby realizing the adjustment of the heater spacing. In order to maintain the symmetry and stability of the shape of the heating body, the control strategy requires that the extension action of all telescopic parts 310 is performed synchronously. The control system ensures the consistent displacement of each heating plate by monitoring the position feedback of the telescopic components, thus avoiding uneven heat field distribution due to local deformation.

[0042] The interval between the first heater 100 and the second heater 200 is greater than 18 mm. The interval between the first heater 100 and the second heater 200 is greater than 18 mm, which can reduce the intensity of heat radiation, reduce thermal interference between heaters, and help improve the thermal stability of the device. The first heater 100 and the second heater 200 are cylindrical structures, respectively, and the interval between the first heater 100 and the second heater 200 is the horizontal distance between the outer wall surface of the first heater 100 and the inner wall surface of the second heater 200.

[0043] A larger spacing distance helps to form a more uniform thermal field distribution. In the process of single crystal silicon growth, the uniformity of the temperature gradient is a key factor affecting the quality of the crystal. By increasing the distance between the heaters, the direct superposition effect of the heat flow can be reduced, local overheating can be reduced, and the temperature of the entire growth area can be made more stable and uniform, which is conducive to improving the internal structure and performance of the growing single crystal silicon rod. In the process of single crystal silicon growth, the control of oxygen content is the key to ensuring the purity and performance of the crystal. By increasing the spacing between the heaters, the time that the outer wall of the crucible is exposed to direct thermal radiation can be reduced, thereby reducing the temperature of the outer wall and reducing the process of oxygen diffusion into the molten silicon through the crucible wall at high temperature, which helps to further reduce the oxygen content of the growing silicon rod.

[0044] The present application also provides a control method for a single crystal silicon growth furnace, which is applicable to the single crystal silicon growth furnace in the above-mentioned embodiment, and the control method includes: in the melting stage, controlling the first heater 100 to operate for a first predetermined period of time, and then controlling the second heater 200 to operate; after the material is melted, controlling the first heater 100 to operate at a first power threshold, and controlling the second heater 200 to operate at a second power threshold, wherein the first power threshold is less than the second power threshold; thereafter, controlling the second heater 200 to move in a direction away from the first heater 100.

[0045] In the melting stage, by running the first heater 100 for a first predetermined period of time and then starting the second heater 200, the heating load can be effectively shared during the silicon material melting process, avoiding long-term high-power operation of a single heater, thereby reducing overall power consumption. The coordinated control of the first heater 100 and the second heater 200 can more finely adjust the temperature distribution and temperature gradient of the thermal field in the growth furnace. In the growth stage after melting, by adjusting the power of the two heaters, the crystal growth rate and crystal quality can be better controlled, avoiding abnormal crystal growth caused by temperature fluctuations.

[0046] The first heater 100 reduces its power after the melting stage, and the second heater 200 intervenes in time, which can reduce the long-term high-temperature baking of the outer wall of the crucible, thereby reducing the oxygen content in the single crystal silicon rod. Experimental data show that the oxygen content can be reduced by at least 15%, significantly improving the purity and crystal quality of the single crystal silicon rod. Through the power control of the first heater 100 and the second heater 200, it is possible to avoid overheating of a local area of ​​the growth furnace, ensure the temperature uniformity during the crystal growth process, and reduce the defects and scrap rate of crystal growth.

[0047] In the melting stage, the first predetermined time is 1h to 3h; and / or, the operating power of the first heater 100 is 50% to 70% of the operating power of the second heater 200. In the melting stage, the first heater 100 is first turned on and operated for 1h to 3h, which can preheat the crucible and effectively share the heating load of the second heater 200, avoiding long-term high-power operation of a single heater. The first heater 100 is operated at 50% to 70% of the operating power of the second heater 200, which can ensure rapid melting while sharing part of the heating load of the second heater 200 through the first heater 100.

[0048] In the present application, after the first heater 100 runs for a first predetermined time, the power of the first heater 100 is reduced to a first power threshold; wherein the first power threshold is 30% to 50% of the maximum power of the first heater 100. After the melting stage, by appropriately reducing the power of the first heater 100, the temperature gradient in the growth furnace can be more finely controlled. Reduce temperature fluctuations during crystal growth. In addition, by reducing the power of the first heater 100 and controlling the power increase of the second heater 200 at the same time, it is beneficial to reduce the high temperature baking of the outer wall of the crucible, thereby achieving an oxygen reduction effect.

[0049] Further, in the process of reducing the power of the first heater 100 to the first power threshold, the operating power of the second heater 200 is controlled to gradually increase to the second power threshold at a predetermined rate. In the process of single crystal silicon growth, the temperature distribution of the thermal field is crucial to the quality and rate of crystal growth. By dynamically adjusting the power of the two heaters, accurate control of the thermal field can be achieved to ensure that the crystal growth is carried out under the optimal temperature gradient. When the power of the first heater 100 is reduced, its heating capacity for the crystal growth area is weakened, which may cause the temperature gradient to change and affect the growth conditions. At this time, by gradually increasing the power of the second heater 200, the impact of the power reduction of the first heater can be compensated to maintain the stable state of the thermal field. The power increase of the second heater 200 adopts a predetermined rate, rather than directly adjusting to the maximum power. The purpose of this is to avoid the sudden change of power from impacting the thermal field and affecting the uniformity and stability of crystal growth. Through smooth power adjustment, it can be ensured that the temperature change of the thermal field is gentle and the impact on the growth process is minimized.

[0050] The setting of the first power threshold and the second power threshold is based on the specific process and thermodynamic calculation. The first power threshold ensures that the first heater 100 can still meet the basic heating requirements after the power is reduced to prevent the temperature from being too low. The second power threshold is the target power of the second heater 200 after compensating for the power reduction of the first heater, ensuring that the temperature distribution of the entire thermal field is in an ideal state and meets the temperature requirements for crystal growth.

[0051] By dynamically adjusting the power distribution of the heater at different stages of the growth process, energy consumption can be minimized while ensuring the thermal field conditions required for the growth of single crystal silicon. For example, after the melt stage, as the power demand of the first heater 100 decreases, the thermal field stability during the growth process can be maintained through the power compensation of the second heater 200, thereby reducing power consumption as a whole. While reducing the power of the first heater 100, gradually increasing the power of the second heater 200 can finely control the temperature gradient and thermal field distribution in the growth furnace. In the process of reducing the power of the first heater 100, appropriately increasing the power of the second heater 200 can reduce the long-term high-temperature baking of the outer wall of the crucible, thereby reducing the oxygen content inside the crystal during the growth of single crystal silicon. Dynamic adjustment of power helps to manage the thermal stress of the equipment. While the power of the first heater 100 is reduced, the power compensation of the second heater 200 can avoid deformation or damage of the heater caused by local overheating, extend the service life of the equipment, and reduce maintenance costs.

[0052] Furthermore, in the specific implementation process, when the material is melted and reaches the preset temperature condition, the power of the second heater 200 is controlled to remain unchanged. At the same time, in order to reduce the high-temperature baking of the outer wall of the crucible 410, the telescopic component 310 is controlled to be pushed out, so that the distance between the second heater 200 and the first heater 100 is increased. The goal is to reduce the temperature of the outer wall of the crucible 410, reduce the high-temperature oxidation of the graphite crucible in the contact area with the air, and then reduce the oxygen content in the crystal. By adjusting the heater spacing, the distribution of heat around the crucible can be changed to reduce unnecessary heat loss. During the entire single crystal rod growth process, the heater spacing can be dynamically adjusted according to actual needs, which can better adapt to temperature fluctuations during the growth process, maintain the stability and uniformity of the thermal field, and avoid crystal growth failure or quality degradation caused by uneven temperature distribution.

[0053] The growth furnace of the present application includes a furnace body 400 and a crucible 410. The crucible 410 is located at the center of the furnace body 400 and is used to hold molten silicon material. The crucible is usually made of materials such as graphite and has good thermal stability and chemical stability. The size and shape design of the crucible need to take into account the process requirements for the growth of single crystal rods, such as diameter, length, and temperature gradient of crystal rod growth. The first heater 100 and the second heater 200 are sequentially sleeved on the outside of the crucible 410 to heat the crucible 410. The first heater is sleeved on the direct outer layer of the crucible 410, and its main function is to provide initial heating and maintain the high temperature environment required for crystal growth. The first heater can be a resistance heater, which is wound by a high temperature resistant resistance wire and is designed to fit the cylindrical or slightly tapered shape of the crucible tightly to ensure the uniformity and efficiency of heat transfer. The second heater is arranged outside the first heater 100, leaving a certain interval between the first heater and the first heater for auxiliary heating and thermal field regulation. The second heater can also adopt a resistance heating method and be designed as a deformable heating body, such as a combination of arc-shaped heating plates 213. By adjusting the telescopic component 310, the distance between the heating plates is changed, thereby dynamically adjusting the heating area and the heating intensity, and optimizing the thermal field distribution. The telescopic component 310 is used to adjust the distance between the first heater 100 and the second heater 200. In this embodiment, the telescopic component can be an electric telescopic rod, a pneumatic telescopic cylinder, or an automatic telescopic mechanism based on the principle of thermal expansion. The drive system controls the telescopic action of the telescopic component, is connected to the temperature detection component signal, and adjusts the heater spacing according to the real-time temperature information, thereby controlling the thermal field distribution. In order to improve the uniformity and quality of crystal growth, thermal field optimization design is the key. In this embodiment, by controlling the power distribution of the first heater 100 and the second heater 200 and adjusting the distance between the two heaters, the temperature gradient and distribution of the thermal field can be accurately controlled to avoid local overheating or insufficient cooling, and reduce defects in the crystal growth process.

[0054] When the first heater 100 and the second heater 200 work at the same time, the power of the second heater 200 is greater than the power of the first heater 100. At this time, the first heater 100 takes away part of the heat to avoid high-temperature and long-term baking of the crucible 410. In the heating stage, the first heater 100 and the second heater 200 work at the same time to provide sufficient heat for heating, thereby shortening the working hours. In this stage, the power of the first heater 100 is 10kw~25kw. In the stages of seeding, shoulder release / shoulder rotation, equal diameter, and finishing, the power of the first heater 100 is 5kw~10kw, and the power of the second heater 200 is 80kw.

[0055] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0056] According to the single crystal silicon growth furnace provided in the present application, it includes a furnace body, a first heater 100, a second heater 200 and an adjustment component 300. The first heater 100 is sleeved on the furnace body, the second heater 200 is sleeved on the first heater 100, and a gap is set between the first heater 100, the second heater 200 is deformably set, the adjustment component 300 is set between the first heater 100 and the second heater 200, the adjustment component 300 is respectively connected to the first heater 100 and the second heater 200, and at least a part of the adjustment component 300 is movably set to drive the first heater 100 and / or the second heater 200 to move, thereby adjusting the distance between the first heater 100 and the second heater 200. This arrangement can heat the furnace body simultaneously through the first heater 100 and the second heater 200, or heat the furnace body through the first heater 100 or the second heater 200 alone. Combined with adjusting the distance between the two layers of heaters, the temperature gradient in the growth furnace can be accurately controlled, and by dynamically adjusting the heating power of the first heater 100 and the second heater 200, the time that the outer wall of the furnace body is subjected to high-temperature baking for a long time can be reduced, thereby reducing the oxygen content in the grown single crystal silicon rods and improving the production quality of the single crystal silicon rods.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A single crystal silicon growth furnace, characterized in that: include: Crucible; A first heater (100) is sleeved on the crucible; a second heater (200) which is sleeved on the first heater (100) and is spaced apart from the first heater (100); the second heater (200) is deformably arranged; An adjusting component (300) is arranged between the first heater (100) and the second heater (200), and the adjusting component is connected to the first heater (100) and the second heater (200) respectively. At least part of the adjusting component is movably arranged to drive the first heater (100) and / or the second heater (200) to move, thereby adjusting the distance between the first heater (100) and the second heater (200).

2. The single crystal silicon growth furnace according to claim 1, characterized in that: The first heater (100) comprises: A first heating body (110), the first heating body (110) is a cylindrical structure, the first heating body (110) is sleeved on the outside of the crucible, and along the axial direction of the first heating body (110), the first heating body (110) comprises a first end surface (111) and a second end surface (112) which are arranged opposite to each other; A first support leg (120) is arranged on the second end surface (112) and is electrically connected to the first heating body (110). There are at least two first support legs (120), and at least two first support legs (120) are arranged at intervals along the circumferential direction of the first heating body (110). Each of the first support legs (120) is respectively connected to a power source to supply power to the first heating body (110).

3. The single crystal silicon growth furnace according to claim 2, characterized in that: The second heater (200) comprises: A second heating body (210), the second heating body (210) being a cylindrical structure, the second heating body (210) being sleeved on the outside of the first heating body (110), and along the axial direction of the second heating body (210), the second heating body (210) comprising a third end surface (211) and a fourth end surface (212) which are arranged opposite to each other; a second support leg (220), arranged on the fourth end surface (212) and electrically connected to the second heating body (210); the second support legs (220) are at least two, and at least two second support legs (220) are arranged at intervals along the circumference of the second heating body (210); each second support leg (220) is respectively connected to a power source to supply power to the second heating body (210); Wherein, the first end surface (111) and the third end surface (211) are arranged flush with each other.

4. The single crystal silicon growth furnace according to claim 3, characterized in that: Taking the axial direction of the second heating body (210) as the height direction, the height of the second heating body (210) is 150 mm to 200 mm; and / or, The height of the first heating body (110) is greater than the height of the second heating body (210), and the distance between the second end surface (112) and the fourth end surface (212) is 80 mm to 180 mm.

5. The single crystal silicon growth furnace according to claim 1, characterized in that: A temperature detection component is provided in the crucible, and the regulating assembly (300) comprises: a telescopic component (310), wherein the telescopic component (310) is telescopically arranged, and two ends of the telescopic component (310) are respectively connected to the first heater (100) and the second heater (200); A driving component is connected to the telescopic component (310) by driving, the driving component is connected to the temperature detection component by signal, and the driving component controls the telescopic displacement of the telescopic component (310) according to temperature information of the temperature detection component.

6. The single crystal silicon growth furnace according to claim 1, characterized in that: The interval between the first heater (100) and the second heater (200) is greater than 18 mm.

7. A control method for a single crystal silicon growth furnace, applicable to the single crystal silicon growth furnace according to any one of claims 1 to 6, characterized in that: The control method comprises: In the melting stage, after controlling the first heater (100) to operate for a first predetermined time, the second heater (200) is controlled to operate; After the material is melted, controlling the first heater (100) to operate at a first power threshold, and controlling the second heater (200) to operate at a second power threshold, wherein the first power threshold is smaller than the second power threshold; Then, the second heater (200) is controlled to move in a direction away from the first heater (100).

8. The control method of a single crystal silicon growth furnace according to claim 7, characterized in that: In the melting stage, the first predetermined time is 1 hour to 3 hours; and / or, The operating power of the first heater (100) is 50% to 70% of the operating power of the second heater (200).

9. The control method of a single crystal silicon growth furnace according to claim 7, characterized in that: After the first heater (100) operates for a first predetermined time period, reducing the power of the first heater (100) to the first power threshold; Wherein, the first power threshold is 30% to 50% of the maximum power of the first heater (100).

10. The control method of a single crystal silicon growth furnace according to claim 9, characterized in that: In the process of reducing the power of the first heater (100) to the first power threshold, The operating power of the second heater (200) is controlled to gradually increase to the second power threshold at a predetermined rate.

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