Cooling unit, cooling device and single crystal furnace

Abstract

The invention discloses a cooling unit, a cooling device and a single crystal furnace, the cooling unit is applied to the single crystal furnace, the cooling unit comprises an inner cylinder and an outer cylinder which are coaxially sleeved, and an annular top plate and an annular bottom plate which are connected with the inner cylinder and the outer cylinder, and the inner cylinder, the outer cylinder, the annular top plate and the annular bottom plate jointly define an annular cavity; the first partition plates and the second partition plates are arranged in the annular cavity, the side walls of the first partition plates and the side walls of the second partition plates are connected to the inner cylinder and the outer cylinder correspondingly, one end of each first partition plate is connected to the top plate, and a first gap is formed between the other end of each first partition plate and the bottom plate; one end of the second partition plate is connected to the bottom plate, and a second gap is formed between the other end of the second partition plate and the top plate; the first partition plates and the second partition plates are arranged at intervals in a staggered mode along the periphery of the inner cylinder, and therefore a snake-shaped refrigerant pipeline is formed. According to the invention, high-precision dynamic regulation and control of the front edge temperature gradient G of the solid-liquid interface of the crystal bar can be realized.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and more particularly to a cooling unit, a cooling device, and a single crystal furnace. Background Art

[0002] During ingot growth, the V / G ratio (V is the single crystal pulling speed, G is the temperature gradient at the solid-liquid interface front) is a key characteristic parameter that determines the distribution of crystal defects. Its value is primarily influenced by the thermal field structure and operating process parameters. Theoretical and engineering practice have shown that the key condition for achieving defect-free, perfect single crystal growth is to control the V / G ratio at the solid-liquid interface front within an extremely small threshold range. When this ratio is too large, COPs (primarily occurring micro-defects) are easily formed within the single crystal silicon, while too small a ratio can induce A / B-type dislocation defects.

[0003] During the ingot growth process, as the quartz crucible's position in the heat field continues to rise, the depth of the silicon melt inside the crucible gradually decreases, causing dynamic changes in the heat transfer conditions from the heater to the solid-liquid growth interface. This results in a time-varying temperature gradient G at the ingot's solid-liquid interface front, making it extremely challenging to achieve perfect single crystal growth conditions throughout the entire ingot growth cycle. Summary of the Invention

[0004] According to one aspect of the present application, a cooling unit is provided for use in a single crystal furnace. The cooling unit comprises:

[0005] An inner cylinder and an outer cylinder are coaxially sleeved, and an annular top plate and an annular bottom plate are connected to the inner cylinder and the outer cylinder, wherein the inner cylinder, the outer cylinder, the annular top plate and the annular bottom plate together form an annular cavity;

[0006] a plurality of first and second partition plates, wherein the first and second partition plates are disposed in the annular cavity, sidewalls of the first and second partition plates being connected to the inner cylinder and the outer cylinder, respectively; one end of the first partition plate being connected to the top plate, a first gap being defined between the other end of the first partition plate and the bottom plate; and one end of the second partition plate being connected to the bottom plate, a second gap being defined between the other end of the second partition plate and the top plate;

[0007] The first partition plates and the second partition plates are alternately arranged along the outer circumference of the inner tube, thereby forming a serpentine refrigerant pipeline.

[0008] In some embodiments of the present application, the cooling unit is used to be sleeved around the periphery of the crystal rod, and the angle between the central axis of the cooling unit and the central axis of the crystal rod is 0° to 45°.

[0009] According to another aspect of the present application, a cooling device is provided for use in a single crystal furnace, the cooling device comprising:

[0010] One or more cooling units as described above, when there are multiple cooling units, the multiple cooling units are arranged in a radial direction based on the central axis and connected by the following refrigerant pipe assembly;

[0011] A refrigerant pipe assembly, the refrigerant pipe assembly includes a refrigerant inlet pipe and a refrigerant outlet pipe that are independently arranged. One or more nested refrigerant inlet channels are provided in the refrigerant inlet pipe, and each of the refrigerant inlet channels is connected to the annular cavity of each of the cooling units in a one-to-one manner. One or more nested refrigerant outflow channels are provided in the refrigerant outflow pipe, and each of the refrigerant outflow channels is connected to the annular cavity of each of the cooling units in a one-to-one manner.

[0012] In some embodiments of the present application, the cooling device further comprises:

[0013] A flow regulating unit, comprising one or more flow regulating valves, each of which is disposed at the inlet end of each of the refrigerant inflow channels in a one-to-one correspondence, for regulating the refrigerant flow of the corresponding cooling unit;

[0014] A temperature acquisition unit, comprising one or more temperature sensors, each of which is disposed at the outlet end of each of the refrigerant outflow channels in a one-to-one correspondence, and is used to collect the outlet refrigerant temperature of the corresponding cooling unit;

[0015] A control element, which is electrically connected to the flow regulating unit and the temperature collecting unit, and is configured as follows:

[0016] Obtaining the outlet refrigerant temperature collected by each temperature sensor;

[0017] comparing the outlet refrigerant temperature with a preset temperature curve for each stage of the crystal growth process;

[0018] The opening of each flow regulating valve is controlled according to the comparison result to adjust the refrigerant flow of each cooling unit.

[0019] In some embodiments of the present application, the cooling device further comprises:

[0020] A flow regulating unit, comprising one or more flow regulating valves, each of which is disposed at the inlet end of each of the refrigerant inflow channels in a one-to-one correspondence, for regulating the refrigerant flow of the corresponding cooling unit;

[0021] A temperature acquisition unit, comprising one or more temperature sensors, each of which is disposed in a corresponding central region of each cooling unit, for acquiring the surface temperature of the region on the crystal ingot corresponding to each cooling unit;

[0022] A control element, which is electrically connected to the flow regulating unit and the temperature collecting unit, and is configured as follows:

[0023] Acquiring the surface temperature collected by each of the temperature sensors;

[0024] The opening of each flow regulating valve is controlled according to the surface temperature to adjust the refrigerant flow of each cooling unit.

[0025] In some embodiments of the present application, the cooling device further comprises:

[0026] Refrigerant main pipeline;

[0027] One or more refrigerant branch pipes, each refrigerant inflow channel is connected to the refrigerant main pipe through a corresponding refrigerant branch pipe, and each refrigerant branch pipe is provided with a flow regulating valve.

[0028] In some embodiments of the present application, the cooling device further comprises:

[0029] Refrigerant return pipe;

[0030] One or more return branch pipes, each refrigerant outflow channel is connected to the refrigerant return pipe through a corresponding return branch pipe, and each return branch pipe is provided with a temperature sensor.

[0031] In some embodiments of the present application, there is a third gap between adjacent cooling units.

[0032] In some embodiments of the present application, the cooling device further comprises:

[0033] One or more groups of blocking components, wherein one group of blocking components is provided between adjacent cooling units to block the third gap;

[0034] Among them, each group of the sealing components includes an inner annular sealing plate and an outer annular sealing plate that are coaxially sleeved, the inner diameter of the inner annular sealing plate is consistent with the inner diameter of the annular cavity of the cooling unit, and the outer diameter of the outer annular sealing plate is consistent with the outer diameter of the annular cavity of the cooling unit.

[0035] According to another aspect of the present application, a single crystal furnace is provided, comprising:

[0036] a furnace body with a furnace cavity provided therein;

[0037] a crucible, disposed in the furnace chamber;

[0038] The cooling device described in any one of the above is arranged in the furnace cavity above the crucible.

[0039] The cooling unit, cooling device and single crystal furnace of the present application can accurately control the surface temperature of the cooling unit, realize fine control of the cooling intensity of the crystal rod near the solid-liquid interface, and thus effectively solve the time-varying problem of the solid-liquid interface temperature gradient G caused by the rising position of the quartz crucible in the thermal field during the growth of the crystal rod, and realize high-precision dynamic control of the temperature gradient G at the front of the solid-liquid interface of the crystal rod. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The above and other purposes, features, and advantages of the present application will become more apparent through a more detailed description of the embodiments of the present application in conjunction with the accompanying drawings. The accompanying drawings are intended to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation of the present application. In the drawings, the same reference numerals generally represent the same components or steps.

[0041] Figure 1 A schematic structural diagram of a cooling unit according to an embodiment of the present application is shown.

[0042] Figure 2 A three-dimensional schematic diagram of a cooling device according to an embodiment of the present application is shown.

[0043] Figure 3 A side view of a cooling device according to an embodiment of the present application is shown.

[0044] Figure 4 A schematic structural diagram of a cooling device according to another embodiment of the present application is shown.

[0045] Figure 5 A schematic diagram of the working conditions of growing single crystal silicon rods using a conventional cooling device in the related art is shown.

[0046] Figure 6 A schematic diagram of the working conditions of growing single crystal silicon rods using the cooling device of the present application is shown. DETAILED DESCRIPTION

[0047] In the following description, a large number of specific details are provided to provide a more thorough understanding of the present application. However, it will be apparent to those skilled in the art that the present application can be implemented without one or more of these details. In other examples, some technical features well known in the art are not described in order to avoid confusion with the present application.

[0048] It should be understood that the present application can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to make the disclosure thorough and complete and to fully convey the scope of the present application to those skilled in the art. In the drawings, the dimensions and relative sizes of layers and regions may be exaggerated for clarity. Like reference numerals throughout represent like elements.

[0049] During the ingot growth process, as the quartz crucible's position in the heat field continues to rise, the depth of the silicon melt inside the crucible gradually decreases, causing dynamic changes in the heat transfer conditions from the heater to the solid-liquid growth interface. This results in a time-varying temperature gradient G at the ingot's solid-liquid interface front, making it extremely challenging to achieve perfect single crystal growth conditions throughout the entire ingot growth cycle.

[0050] As the semiconductor industry moves toward ultra-large 12-inch diameter ingots, higher requirements are placed on the precision control of the temperature gradient G at the solid-liquid interface and the pulling speed V. For 12-inch semiconductor wafers in particular, to meet the stringent requirement of achieving a flawless, perfect single crystal structure from the center to the edge, the radial uniformity of the temperature gradient G at the growth interface must be precisely controlled. This constitutes a core difficulty in 12-inch semiconductor single crystal silicon growth technology.

[0051] In related technologies, conventional cooling devices such as water-cooling screens and water-cooling jackets serve as key components for regulating the temperature distribution of thermal fields. Their principle is to efficiently exchange the radiant heat flux on the surface of the crystal rod through the cooling water medium, thereby achieving overall regulation of the temperature gradient G at the front of the solid-liquid interface of the crystal rod. However, due to their uniform cooling structure, they are unable to regulate the radial distribution of the temperature field at the growth interface, making it difficult to break through the existing process window limitations for defect-free single crystal growth and unable to meet the stringent requirements of large-size crystal rods for the uniformity of the V / G ratio.

[0052] For example, Figure 5 Figure 1 shows a schematic diagram of the growth of single crystal silicon ingots using conventional cooling devices such as water-cooled screens and water-cooled jackets. Because these conventional cooling devices lack the ability to control the radial distribution of the temperature gradient at the growth interface, the solid-liquid growth interface exhibits a significantly convex curvature, which in turn results in a significantly high radial resistivity gradient for the single crystal silicon ingots.

[0053] In order to solve one or more of the above problems, the present application provides a cooling unit applied to a single crystal furnace, comprising:

[0054] An inner cylinder and an outer cylinder are coaxially sleeved, and an annular top plate and an annular bottom plate are connected to the inner cylinder and the outer cylinder, wherein the inner cylinder, the outer cylinder, the annular top plate and the annular bottom plate together form an annular cavity;

[0055] a plurality of first and second partition plates, wherein the first and second partition plates are disposed in the annular cavity, sidewalls of the first and second partition plates being connected to the inner cylinder and the outer cylinder, respectively; one end of the first partition plate being connected to the top plate, a first gap being defined between the other end of the first partition plate and the bottom plate; and one end of the second partition plate being connected to the bottom plate, a second gap being defined between the other end of the second partition plate and the top plate;

[0056] The first partition plates and the second partition plates are alternately arranged along the outer circumference of the inner tube, thereby forming a serpentine refrigerant pipeline.

[0057] According to the cooling unit of the present application, the surface temperature of the cooling unit can be accurately controlled, and the cooling intensity of the crystal rod near the solid-liquid interface can be finely controlled, thereby effectively solving the time-varying problem of the solid-liquid interface temperature gradient G caused by the rising position of the quartz crucible in the thermal field during the growth of the crystal rod, and realizing high-precision dynamic control of the temperature gradient G at the front of the solid-liquid interface of the crystal rod.

[0058] In order to thoroughly understand the present application, detailed steps and structures will be provided in the following description to illustrate the technical solution proposed by the present application. The preferred embodiments of the present application are described in detail below. However, in addition to these detailed descriptions, the present application may also have other implementation methods.

[0059] Example 1

[0060] According to one aspect of the present application, a cooling unit 100 is provided for use in a single crystal furnace. Figure 1 As shown, the cooling unit 100 includes an inner cylinder 111 and an outer cylinder 112 coaxially arranged, and an annular top plate 113 and an annular bottom plate 114 connecting the inner cylinder 111 and the outer cylinder 112. The inner cylinder 111, the outer cylinder 112, the annular top plate 113 and the annular bottom plate 114 together form an annular cavity; a plurality of first partition plates 121 and second partition plates 122 are arranged in the annular cavity, and the side walls of the first partition plates 121 and the second partition plates 122 are respectively connected to the inner cylinder 111 and the outer cylinder 112, and one end of the first partition plate 121 is connected to the top plate, and a first gap is formed between the other end of the first partition plate 121 and the bottom plate, and one end of the second partition plate 122 is connected to the bottom plate, and a second gap is formed between the other end of the second partition plate 122 and the top plate; the first partition plates 121 and the second partition plates 122 are staggered along the outer circumference of the inner cylinder 111, thereby forming a serpentine refrigerant pipeline.

[0061] During the crystal ingot growth process, the cooling unit 100 of this embodiment can be mounted around the crystal ingot, working in conjunction with the heater, crucible, and other components within the single crystal furnace. Multiple staggered first and second partitions 121, 122 divide the interior of the annular cavity into a serpentine refrigerant conduit. After entering the annular cavity, the refrigerant, guided by the first and second partitions 121, 122, moves along the serpentine refrigerant conduit in a combined radial and circumferential direction. Through a heat exchange mechanism, it absorbs the radiant heat flux from the crystal ingot surface and is ultimately discharged from the annular cavity, achieving targeted regulation of the temperature gradient G at the front edge of the solid-liquid interface of the crystal ingot.

[0062] It is worth emphasizing that by further adjusting the refrigerant flow rate of the cooling unit 100, the surface temperature of the cooling unit 100 can be accurately controlled, thereby achieving refined control of the cooling intensity of the crystal rod near the solid-liquid interface.

[0063] In addition, as the crucible continues to rise during the crystal growth process, the relative position of the solid-liquid interface will dynamically migrate along the axis of the crystal rod, causing the surrounding thermal field distribution to exhibit time-varying characteristics. In this embodiment, the cooling capacity of the cooling unit 100 can be dynamically matched with the time-varying characteristics of the thermal field distribution by adjusting the refrigerant flow of the cooling unit 100. For example, when the crucible rises and the cooling unit 100 is closer to the liquid surface of the high-temperature melt, the refrigerant flow of the cooling unit 100 can be reduced to reduce the cooling intensity. This control mechanism effectively solves the time-varying problem of the solid-liquid interface temperature gradient G caused by the rising position of the quartz crucible in the thermal field during the growth of the crystal rod, and realizes high-precision dynamic control of the temperature gradient G at the front of the solid-liquid interface of the crystal rod through the flow control strategy.

[0064] Compared with conventional cooling devices such as traditional water-cooled screens and water-cooled jackets, the cooling unit 100 of this embodiment constructs a serpentine refrigerant pipe through multiple first partition plates 121 and second partition plates 122 that are staggered. On the one hand, it significantly extends the flow path length of the refrigerant in the annular cavity and increases the heat exchange time between the refrigerant and the crystal rod surface. On the other hand, it forces the refrigerant to change its flow direction multiple times through the geometric constraints of the flow channel, inducing a turbulent effect, thereby improving the heat exchange coefficient compared to the traditional straight channel structure, thereby greatly enhancing the heat exchange efficiency and temperature control accuracy of the cooling unit 100.

[0065] In some embodiments, as Figure 1 As shown, the cooling unit 100 further includes a refrigerant flow channel interface, which is located on the annular top plate 113 and communicates with the annular cavity. The refrigerant flow channel interface includes a refrigerant inlet 131 for introducing refrigerant and a refrigerant outlet 132 for discharging refrigerant.

[0066] In some embodiments, the dimensions of the inner and outer cylinders 111 and 112 are designed based on the specific requirements of ingot growth. The inner diameter of the inner cylinder 111 is determined based on the diameter of the ingot. Generally, the inner diameter of the inner cylinder 111 is larger than the ingot diameter by a specified length (e.g., 30 mm to 300 mm) to ensure that the ingot can pass through the inner cylinder 111 smoothly without colliding with the ingot. The outer diameter of the outer cylinder 112 is determined based on the installation space of the entire cooling unit 100 and the heat exchange efficiency.

[0067] The annular top plate 113 and the annular bottom plate 114 are connected to the inner tube 111 and the outer tube 112 via a sealed connection. In actual production, sealing can be achieved through welding or flange connections. If welding is used, appropriate welding processes and materials must be selected to ensure the seal and strength of the welded joints. If flange connections are used, sealing gaskets must be installed on the flange sealing surfaces to ensure a secure seal. High-strength bolts and nuts can also be used for fastening to ensure connection reliability.

[0068] The annular top plate 113 is provided with a refrigerant inlet 131 and a refrigerant outlet 132 that are connected to the annular cavity. The positions and sizes of the refrigerant inlet 131 and the refrigerant outlet 132 need to be reasonably designed according to the flow rate and flow velocity of the refrigerant. Generally speaking, the diameters of the refrigerant inlet 131 and the refrigerant outlet 132 should ensure that the refrigerant can enter and flow out of the annular cavity at a suitable flow rate to improve the heat exchange efficiency. At the same time, the positions of the refrigerant inlet 131 and the refrigerant outlet 132 should be reasonably arranged to ensure that the refrigerant can be evenly distributed in the annular cavity. For example, the refrigerant inlet 131 can be set on one side of the annular top plate 113, and the refrigerant outlet 132 can be set on the other side, so that the refrigerant forms a relatively uniform flow path in the annular cavity.

[0069] The selection of the refrigerant is crucial to the performance of the cooling unit 100. During the ingot growth process, commonly used refrigerants include liquid water, compressed air, or other fluids, which can be selected based on actual conditions and are not limited thereto.

[0070] In some embodiments, the cooling unit 100 is used to be sleeved around the periphery of the crystal rod, and there may be a certain angle between the central axis of the cooling unit 100 and the central axis of the crystal rod. For example, the angle is 0° to 45°. This design breaks through the limitation that traditional water-cooling screens and water-cooling jackets can only be coaxially sleeved around the periphery of the crystal rod. By adjusting the relative angle between the cooling unit 100 and the crystal rod, the directional control of the temperature gradient distribution in the asymmetric thermal field can be achieved, which is particularly suitable for the shouldering stage in the early growth of large-size crystal rods or the temperature field optimization of special crystal types (such as elliptical cross-sections).

[0071] Example 2

[0072] According to another aspect of the present application, a cooling device 200 is provided for use in a single crystal furnace. Figures 2 to 4 As shown, the cooling device 200 includes: a refrigerant pipe assembly and one or more cooling units 210. When there are multiple cooling units 210, the multiple cooling units 210 are arranged in a radial direction based on the central axis and are connected through the following refrigerant pipe assembly; the refrigerant pipe assembly includes a refrigerant inlet pipe 221 and a refrigerant outlet pipe 222 that are independently arranged. One or more nested refrigerant inlet channels 2211 are provided in the refrigerant inlet pipe 221, and each refrigerant inlet channel 2211 is connected to the annular cavity of each cooling unit 210 in a one-to-one manner; one or more nested refrigerant outflow channels 2221 are provided in the refrigerant outflow pipe 222, and each refrigerant outflow channel 2221 is connected to the annular cavity of each cooling unit 210 in a one-to-one manner.

[0073] The cooling unit 210 may be implemented as the cooling unit 100 mentioned above, and reference may be made to the above description, which will not be repeated here.

[0074] Taking the cooling device 200 as an example, which includes a cooling unit 210, a refrigerant pipe assembly is provided on the cooling unit 210, and the refrigerant pipe assembly includes a refrigerant inlet pipe 221 and a refrigerant outlet pipe 222 that are independently arranged. A refrigerant inlet channel 2211 is provided in the refrigerant inlet pipe 221, and the refrigerant inlet channel 2211 is connected to the annular cavity of the cooling unit 210. A refrigerant outflow channel 2221 is provided in the refrigerant outflow pipe 222, and the refrigerant outflow channel 2221 is connected to the annular cavity of the cooling unit 210.

[0075] During the ingot growth process, the cooling device 200 can be installed around the ingot, working in conjunction with the heater, crucible, and other components within the single crystal furnace. Refrigerant enters the annular cavity of cooling unit 210 from the refrigerant inlet via refrigerant inlet pipe 221. Within the annular cavity of cooling unit 210, it flows along the serpentine refrigerant pipe, absorbs radiant heat from the ingot surface, and is then discharged through the refrigerant outlet and refrigerant outflow pipe 222, achieving targeted control of the temperature gradient G at the solid-liquid interface front of the ingot.

[0076] Similarly, by further adjusting the refrigerant flow rate of the cooling device 200, the surface temperature of the cooling unit 210 of the cooling device 200 can be accurately controlled, thereby achieving refined control of the cooling intensity of the crystal rod near the solid-liquid interface.

[0077] In addition, as the crucible continues to rise during the crystal growth process, the relative position of the solid-liquid interface will dynamically migrate along the axis of the crystal rod, causing the surrounding thermal field distribution to exhibit time-varying characteristics. In this embodiment, the cooling capacity of the cooling unit 210 can be dynamically matched with the time-varying characteristics of the thermal field distribution by adjusting the refrigerant flow of the cooling unit 210 in the cooling device 200. For example, when the crucible rises and the cooling unit 210 is closer to the high-temperature melt surface, the refrigerant flow of the cooling unit 210 can be reduced to reduce the cooling intensity. This control mechanism can effectively solve the time-varying problem of the solid-liquid interface temperature gradient G caused by the rising position of the quartz crucible in the thermal field during the growth of the crystal rod, and realizes high-precision dynamic control of the temperature gradient G at the front of the solid-liquid interface of the crystal rod through the flow control strategy.

[0078] Taking the cooling device 200 as an example, which includes multiple cooling units 210, the multiple cooling units 210 are arranged in a radial direction based on the central axis and are connected by a refrigerant pipe assembly. The refrigerant pipe assembly includes a refrigerant inlet pipe 221 and a refrigerant outlet pipe 222 that are independently arranged. The refrigerant inlet pipe 221 is provided with a plurality of nested refrigerant inlet channels 2211, and each refrigerant inlet channel 2211 is connected to the annular cavity of each cooling unit 210 in a one-to-one manner; the refrigerant outflow pipe 222 is provided with a plurality of nested refrigerant outflow channels 2221, and each refrigerant outflow channel 2221 is connected to the annular cavity of each cooling unit 210 in a one-to-one manner.

[0079] During the ingot growth process, the cooling device 200 can be positioned around the ingot, working in conjunction with the heater, crucible, and other components within the single crystal furnace. Refrigerant enters the corresponding cooling unit 210 through each refrigerant inflow channel 2211. Within the annular cavity of cooling unit 210, it flows along the serpentine refrigerant pipe, absorbing radiant heat from the ingot surface before being discharged through the refrigerant outflow pipe 222 corresponding to that cooling unit 210. This achieves targeted control of the temperature gradient G at the front of the solid-liquid interface of the ingot.

[0080] Unlike a cooling device 200 comprising only a single cooling unit 210, a cooling device 200 comprising multiple cooling units 210 independently adjusts the refrigerant flow rate of each cooling unit 210, enabling precise and independent control of the surface temperature of each cooling unit 210. This control method allows for precise regulation of the cooling intensity in each radial region of the ingot, thereby optimizing the radial distribution of the temperature gradient G at the solid-liquid interface front and effectively improving the radial uniformity of the V / G ratio.

[0081] In addition, as the crucible continues to rise during the crystal growth process, the relative position of the solid-liquid interface will dynamically migrate along the axis of the crystal rod, causing the surrounding thermal field distribution to exhibit time-varying characteristics. In this embodiment, the refrigerant flow rate of each cooling unit 210 can be adjusted to dynamically match its cooling capacity with the time-varying characteristics of the thermal field distribution. For example, when the crucible rises and a certain area approaches the high-temperature melt surface, the refrigerant flow rate of the cooling unit 210 at the corresponding position is reduced to reduce the cooling intensity of the area. This control mechanism can effectively solve the time-varying problem of the solid-liquid interface temperature gradient G caused by the rising position of the quartz crucible in the thermal field during the growth of the crystal rod, and realizes high-precision dynamic control of the temperature gradient G at the front of the solid-liquid interface of the crystal rod through the flow control strategy.

[0082] Compared with the global cooling mode of the traditional single cooling unit 210, the multi-unit independent control technology breaks through the technical limitations of the process window for defect-free single crystal growth, provides precise control means for differentiated thermal management of different radial positions of the crystal rod, and ultimately creates key conditions for achieving defect-free and perfect single crystal growth in the entire radial range.

[0083] In some embodiments, as Figure 2 and Figure 3 As shown, the cooling device 200 also includes a flow regulating unit, a temperature acquisition unit and a control element. The flow regulating unit includes one or more flow regulating valves, each of which is correspondingly arranged at the inlet end of each refrigerant inflow channel 2211, for regulating the refrigerant flow of the corresponding cooling unit 210; the temperature acquisition unit includes one or more temperature sensors, each of which is correspondingly arranged at the outlet end of each refrigerant outflow channel 2221, for collecting the outlet refrigerant temperature of the corresponding cooling unit 210; the control element is electrically connected to the flow regulating unit and the temperature acquisition unit, and is configured to: obtain the outlet refrigerant temperature collected by each temperature sensor; compare the outlet refrigerant temperature with the preset temperature curve of each stage in the crystal growth process; and control the opening of each flow regulating valve according to the comparison result to adjust the refrigerant flow of each cooling unit 210.

[0084] The cooling device 200 comprises a closed-loop control system formed by a flow regulating unit, a temperature acquisition unit and a control element. Through the coordinated operation of the flow regulating unit, the temperature acquisition unit and the control element, the closed-loop control system can dynamically optimize the refrigerant flow of each cooling unit 210 in real time according to the real-time changes in the thermal field distribution during the growth of the crystal rod, thereby intelligently regulating the heat dissipation conditions near the surface of the crystal rod. Specifically, when the control element detects that the outlet refrigerant temperature of a cooling unit 210 deviates from the preset process curve, the control element calculates and outputs an adjustment instruction through a built-in algorithm, drives the corresponding flow regulating valve to adjust the opening, so as to increase or decrease the refrigerant flow of the cooling unit 210, strengthen or weaken the cooling intensity of the cooling unit 210, and realize dynamic compensation of the temperature gradient distribution of the growth interface. This precise control mechanism significantly improves the radial uniformity of the V / G ratio during the growth of the crystal rod, effectively suppresses the generation of crystal defects, and significantly improves the growth quality and yield rate of large-size crystal rods.

[0085] In addition, the closed-loop control system supports real-time online configuration of process parameters and can flexibly adjust the preset temperature curve and control strategy according to the growth process requirements of crystal rods of different specifications. It has good versatility and adaptability.

[0086] In other embodiments, the cooling device 200 also includes: a flow regulating unit, a temperature collection unit and a control element, the flow regulating unit includes one or more flow regulating valves, each flow regulating valve is arranged one by one at the inlet end of each refrigerant inflow channel 2211, and is used to regulate the refrigerant flow of the corresponding cooling unit 210; the temperature collection unit includes one or more temperature sensors, each temperature sensor is arranged one by one at the central area of each cooling unit 210, and is used to collect the surface temperature of the area corresponding to each cooling unit 210 on the crystal rod; the control element is electrically connected to the flow regulating unit and the temperature collection unit, and is configured to: obtain the surface temperature collected by each temperature sensor; control the opening of each flow regulating valve according to the surface temperature to adjust the refrigerant flow of each cooling unit 210.

[0087] The cooling device 200 is composed of a closed-loop control system by a flow regulating unit, a temperature acquisition unit and a control element. The closed-loop control system can dynamically optimize the refrigerant flow of each cooling unit 210 in real time according to the real-time changes in the thermal field distribution during the growth of the crystal rod through the coordinated operation of the flow regulating unit, the temperature acquisition unit and the control element, thereby intelligently regulating the heat dissipation conditions near the surface of the crystal rod. Specifically, when the control element detects that the surface temperature of the area corresponding to a cooling unit 210 on the crystal rod is too high or too low, the control element calculates and outputs an adjustment instruction through a built-in algorithm, drives the corresponding flow regulating valve to adjust the opening, so as to increase or decrease the refrigerant flow of the cooling unit 210, strengthen or weaken the cooling intensity of the cooling unit 210, and realize dynamic compensation of the temperature gradient distribution of the growth interface. This precise control mechanism significantly improves the radial uniformity of the V / G ratio during the growth of the crystal rod, effectively suppresses the generation of crystal defects, and significantly improves the growth quality and yield rate of large-size (e.g., 12-inch) crystal rods.

[0088] Similarly, the closed-loop control system supports real-time online configuration of process parameters and can flexibly adjust the preset temperature curve and control strategy according to the growth process requirements of crystal rods of different specifications. It has good versatility and adaptability.

[0089] The temperature sensor of this embodiment may be an infrared temperature sensor, etc., which is not limited.

[0090] In the above embodiment, a closed-loop control system consisting of a flow control unit, a temperature acquisition unit, and a control element is used to independently control each cooling unit 210 in the cooling device 200. By dividing the cooling device 200 into multiple controllable temperature zones (each corresponding to a cooling unit 210), the thermal field characteristics at different axial positions during the crystal ingot growth process can be automatically and differentially controlled.

[0091] The core of the dynamic control mechanism lies in real-time response to the time-varying characteristics of the thermal field: as the crucible continues to rise during the crystal growth process, the relative position of the solid-liquid interface will undergo dynamic migration along the axis of the crystal rod, causing the surrounding thermal field distribution to exhibit time-varying characteristics. The control element collects temperature data through the temperature acquisition units corresponding to each cooling unit 210, controls the opening of the flow control valve corresponding to each cooling unit 210, and adjusts the refrigerant flow of each cooling unit 210, ultimately achieving effective control of the temperature gradient G at the solid-liquid interface front and the radial uniformity of the V / G ratio. For example, when the crucible rises and a certain area approaches the high-temperature melt surface, the control element controls the reduction of the refrigerant flow of the cooling unit 210 at the corresponding position to reduce the cooling intensity of the area.

[0092] Therefore, this application implements intelligent, zoned temperature control for the cooling device 200. Leveraging the independent controllability of each cooling unit 210, precise cooling is implemented based on thermal field differences at different axial positions. Furthermore, through a dynamic control mechanism, the refrigerant flow rate of each cooling unit 210 is automatically adjusted in real time as the crucible position changes, dynamically matching the cooling capacity with the time-varying characteristics of the thermal field distribution. This combination enables high-precision dynamic control of the temperature gradient at the solid-liquid interface front of the crystal ingot, providing a key technical guarantee for perfect single crystal growth.

[0093] In other embodiments, Figure 4 As shown, the cooling device 200 also includes a refrigerant main pipeline and one or more refrigerant branch pipelines. Each refrigerant inflow channel 2211 is connected to the refrigerant main pipeline through a corresponding refrigerant branch pipeline, and each refrigerant branch pipeline is provided with a flow regulating valve.

[0094] Specifically, the refrigerant main pipeline is the backbone of the entire refrigerant distribution system. Its primary function is to receive refrigerant from an external refrigerant supply source and transport it to the various refrigerant distribution pipelines. The diameter of the refrigerant main pipeline is designed based on the overall refrigerant demand of cooling device 200 to ensure sufficient refrigerant flow.

[0095] The refrigerant branch pipes are branched out from the side of the refrigerant main pipe, and the number corresponds to the number of cooling units 210. Each cooling unit 210 is connected to the refrigerant main pipe through a corresponding refrigerant branch pipe, thereby realizing the distribution of refrigerant from the refrigerant main pipe to each cooling unit 210.

[0096] To independently regulate the refrigerant flow rate of each cooling unit 210, each refrigerant branch pipe is provided with a flow control valve. These flow control valves are electrically connected to the control element and can precisely adjust the refrigerant flow rate in the corresponding refrigerant branch pipe according to the instructions issued by the control element.

[0097] It is worth noting that when the cooling device 200 includes only one cooling device 200 , there is correspondingly only one refrigerant branch pipe. In this case, the refrigerant branch pipe and the refrigerant main pipe can be an integrated structure.

[0098] In some embodiments, as Figure 4 As shown, the cooling device 200 also includes a refrigerant return pipe and one or more return branch pipes. Each refrigerant outflow channel 2221 is connected to the refrigerant return pipe through a corresponding return branch pipe, and each return branch pipe is provided with a temperature sensor.

[0099] Specifically, the refrigerant return pipe serves as the main channel for the entire refrigerant return, and is used to collect the refrigerant after heat exchange in each cooling unit 210 and transport it to an external refrigerant processing device.

[0100] The reflux branch pipe is a branch pipe connecting the refrigerant outflow channel 2221 of each cooling unit 210 and the refrigerant return pipe. Each cooling unit 210 is correspondingly provided with a reflux branch pipe.

[0101] In order to achieve accurate monitoring of the heat exchange effect of each cooling unit 210, a temperature sensor is installed on each return branch pipe. The temperature sensor is electrically connected to the control element to transmit the collected refrigerant outlet temperature data to the control element in real time, so that the control element controls the opening of the corresponding flow regulating valve according to the refrigerant outlet temperature of each return branch pipe.

[0102] It is worth noting that when the cooling device 200 includes only one cooling device 200 , there is correspondingly only one return branch pipe. In this case, the return branch pipe and the refrigerant return pipe can be an integrated structure.

[0103] In some embodiments, as Figure 2 and Figure 3 As shown, there is a third gap 230 between adjacent cooling units 210 .

[0104] In some embodiments, the cooling device 200 also includes one or more groups of sealing components, and a group of sealing components is provided between adjacent cooling units 210 to seal the third gap 230; wherein, each group of sealing components includes a coaxially arranged inner annular sealing plate and an outer annular sealing plate, the inner diameter of the inner annular sealing plate is consistent with the inner diameter of the annular cavity of the cooling unit 210, and the outer diameter of the outer annular sealing plate is consistent with the outer diameter of the annular cavity of the cooling unit 210.

[0105] In a cooling device 200 comprising multiple cooling units 210, when adjacent cooling units 210 are arranged radially, a third gap 230 exists between the cooling units 210 due to installation factors and structural design requirements. This third gap 230 not only easily leads to uneven heat radiation from the surface of the crystal ingot, but also may weaken the overall structural strength of the cooling device 200, affecting the stability of the device.

[0106] To optimize the heat exchange performance and structural stability of the cooling device 200 and eliminate the effects of the third gap 230 between adjacent cooling units 210 on the temperature field distribution and mechanical strength, a sealing assembly is provided in the cooling device 200 in this embodiment. The sealing assembly utilizes a double-layer plate structure, with each set of sealing assemblies comprising a coaxially sleeved inner annular sealing plate and an outer annular sealing plate. The inner diameter of the inner annular sealing plate matches the inner diameter of the inner tube of the annular cavity of the cooling unit 210, ensuring a smooth transition on the inner circumference. The outer diameter of the outer annular sealing plate fully matches the outer diameter of the outer tube of the annular cavity of the cooling unit 210, forming a continuous transition on the outer circumference. The above structural design, on the one hand, eliminates the influence of the third gap 230 between adjacent cooling units 210 on the temperature field distribution, avoids local overheating or overcooling, makes the heat flux density distribution on the surface of the crystal rod more uniform, enhances the control accuracy of the cooling device 200 on the temperature gradient of the growth interface, and provides a stable thermal field environment for defect-free growth of the crystal rod; on the other hand, the adjacent cooling units 210 are connected into an integral structure through the sealing component, which significantly improves the vibration resistance and load-bearing capacity of the cooling device 200, prevents structural deformation or fatigue damage caused by stress concentration, and extends the service life of the cooling device 200; on the other hand, the inner and outer annular sealing plates have a smooth transition with the inner and outer peripheral surfaces of the cooling unit 210, so that the inner and outer walls of the cooling unit 210 are smooth and uniform.

[0107] It is worth noting that the third gap 230 between adjacent cooling units 210 may have different sizes depending on actual installation factors, structural design requirements, etc. For example, the third gap 230 between adjacent cooling units 210 is 10 mm to 100 mm, preferably 20 mm to 40 mm, or 10% ± 5% of the diameter of the grown crystal ingot.

[0108] In some embodiments, the cooling device 200 is used to be sleeved around the periphery of the crystal rod, and there may be a certain angle between the central axis of the cooling device 200 and the central axis of the crystal rod. For example, the angle is 0° to 45°. This design breaks through the limitation that traditional water-cooling screens and water-cooling jackets can only be coaxially sleeved around the periphery of the crystal rod. By adjusting the relative angle between the cooling device 200 and the crystal rod, the directional control of the temperature gradient distribution in the asymmetric thermal field can be achieved, which is particularly suitable for the shouldering stage in the early growth of large-size crystal rods or the temperature field optimization of special crystal types (such as elliptical cross-sections).

[0109] In some embodiments, different numbers of cooling units 210 can be combined to obtain cooling devices 200 of different heights according to the requirements of growing crystal rods of different lengths. For example, the height of the cooling device 200 is 50 mm to 600 mm, preferably 200 mm to 400 mm.

[0110] In some embodiments, the inner diameter of the cooling device 200 is larger than the diameter of the grown crystal rod. For example, the inner diameter of the cooling device 200 may be 30 mm to 300 mm larger than the diameter of the grown crystal rod, and preferably 100 mm to 200 mm larger.

[0111] In addition, during the growth of the crystal rod, the bottom of the cooling device 200 is at a certain height away from the silicon melt liquid surface. For example, the bottom of the cooling device 200 is 10mm to 400mm away from the silicon melt liquid surface, preferably 30mm to 150mm. This distance not only ensures a safe distance between the cooling device 200 and the high-temperature molten silicon liquid surface, but also allows the cooling device 200 to be close to the solid-liquid growth interface, thereby effectively controlling the temperature gradient G at the front of the solid-liquid interface of the crystal rod.

[0112] In some embodiments, as Figure 6 FIG2 is a schematic diagram showing the operation of growing a single crystal silicon rod using the cooling device 200 of the present application. The cooling device 200 of the present application can reduce the radial temperature gradient at the front edge of the crystal rod growth interface, making the solid-liquid growth interface flatter and effectively reducing the radial resistivity gradient of the single crystal silicon rod.

[0113] In some embodiments, the oxygen content of the single crystal silicon grown by the cooling device 200 of the present application is distributed in the range of 2 to 20 ppma, and the BMD (Benchmark dose, benchmark dose level) concentration is 1E+6ea / cm 3 ~10E+10ea / cm 3 , the perfect single crystal rate is above 90%.

[0114] For example, Figure 4 The cooling device for growing single crystal silicon rods is further explained. The cooling device includes three cooling units, namely cooling unit A, cooling unit B and cooling unit C. The three cooling units are arranged in the radial direction with the central axis as the reference and are connected by a refrigerant pipe assembly. The refrigerant pipe assembly includes a refrigerant inlet pipe and a refrigerant outlet pipe that are independently arranged. The refrigerant inlet pipe is provided with three nested refrigerant inlet channels, and each refrigerant inlet channel is connected to the refrigerant inlet of each cooling unit in a one-to-one manner; the refrigerant outflow pipe is provided with three nested refrigerant outflow channels, and each refrigerant outflow channel is connected to the refrigerant outlet of each cooling unit in a one-to-one manner.

[0115] The cooling device also includes a refrigerant main pipeline and three refrigerant branch pipelines. Each refrigerant inflow channel is connected to the refrigerant main pipeline through a corresponding refrigerant branch pipeline. Each refrigerant branch pipeline is provided with a flow regulating valve, namely flow regulating valve A, flow regulating valve B and flow regulating valve C.

[0116] The cooling device also includes a refrigerant return pipe and three return branch pipes. Each refrigerant outflow channel is connected to the refrigerant return pipe through a corresponding return branch pipe. Each return branch pipe is provided with a temperature sensor, namely temperature sensor A, temperature sensor B and temperature sensor C.

[0117] The cooling device further includes a control element, which is electrically connected to the three flow regulating valves and the three temperature sensors.

[0118] The cooling unit has an inner diameter of 400mm, each unit is 100mm high, and the third gap between adjacent units is 25mm, for a total height of 350mm. The bottom of the cooling unit is 150mm above the silicon melt surface and is designed to grow single crystal silicon rods with a diameter of 300mm.

[0119] In addition, taking into account the lower thermal conductivity of silicon single crystals, there is a difference in the length of the heat transfer path from the latent heat of crystallization on the solid-liquid interface to the surface of the crystal rod during crystal growth. For example, the latent heat in the center of the crystal rod needs to pass through the entire crystal rod to be transferred to the side and the rear end of the crystal rod, while the latent heat generated by the solid-liquid interface at the edge of the crystal rod is quickly transferred to the surface of the crystal rod, and then mainly transferred to the cooling device of the present application by radiation heat transfer and carried out to the outside by the refrigerant. In order to obtain a uniform temperature gradient on the solid-liquid interface from the center to the edge, it is necessary to adjust the heat dissipation boundary conditions on the surface of the crystal rod behind the solid-liquid interface: the farther away from the solid-liquid interface, the more the heat dissipation conditions need to be strengthened, that is, a lower heat dissipation (refrigerant) temperature is required. For example, Figure 4 The distances between cooling unit A, cooling unit B, and cooling unit C and the solid-liquid interface gradually increase. Therefore, while maintaining other growth conditions unchanged, the outlet temperatures of cooling unit A, cooling unit B, and cooling unit C can be set in the control element to gradually increase, that is, the cooling capacity of cooling unit A is greater than the cooling capacity of cooling unit B, and the cooling capacity of cooling unit B is greater than the cooling capacity of cooling unit C, so as to meet the above conditions. For example, while maintaining other growth conditions unchanged, the outlet temperature of cooling unit A is set in the control element to a constant C (the range of C is 20-60 degrees Celsius), the outlet temperature of cooling unit B is set to C+5 degrees Celsius, and the outlet temperature of cooling unit C is set to C+15 degrees Celsius. Of course, in addition to 5 degrees Celsius and 15 degrees Celsius, the outlet temperatures of the three cooling units can also have other temperature differences or change dynamically with the growth position of the crystal rod according to a preset temperature curve, and this is not limited.

[0120] After the single crystal silicon ingot is grown, the height difference between the center and edge of the ingot's growth interface in this embodiment is reduced from approximately 20 mm to approximately 10 mm, compared to the ingots obtained in related technologies. This improvement in interface flatness reaches 50%. This reduction in the height difference at the growth interface significantly improves the uniformity of the temperature gradient. This also improves the uniformity of the V / G ratio across the growth interface, facilitating the growth of perfect single crystals.

[0121] Example 3

[0122] According to another aspect of the present application, a single crystal furnace is provided. The single crystal furnace includes: a furnace body with a furnace cavity disposed therein; a crucible disposed in the furnace cavity; and a cooling device disposed in the furnace cavity above the crucible.

[0123] The cooling device may be implemented as the cooling device 200 mentioned above, and reference may be made to the above description, which will not be repeated here.

[0124] Based on the above description, the cooling unit, cooling device, and single crystal furnace according to the embodiments of the present application can precisely control the surface temperature of the cooling unit, achieving refined control of the cooling intensity of the crystal ingot near the solid-liquid interface. This effectively solves the time-varying problem of the solid-liquid interface temperature gradient G caused by the rising position of the quartz crucible in the thermal field during the crystal ingot growth process, and achieves high-precision dynamic control of the temperature gradient G at the front of the solid-liquid interface of the crystal ingot. In addition, the cooling device can independently control the refrigerant flow rate of each cooling unit, indirectly regulating the crystal ingot growth temperature gradient to appropriately increase or decrease the growth rate of the single crystal silicon, thereby effectively suppressing the generation of crystal defects and significantly improving the growth quality and yield of large-sized crystal ingots.

[0125] In particular, the closed-loop control system composed of a flow regulation unit, a temperature acquisition unit and a control element can, on the one hand, divide the cooling device into multiple controllable temperature zones (each controllable temperature zone corresponds to a cooling unit) to realize intelligent zoning temperature control; on the other hand, through the dynamic control mechanism, the refrigerant flow of each cooling unit can be automatically adjusted in real time as the crucible position changes, so that the cooling capacity of each cooling unit is dynamically matched with the time-varying characteristics of the thermal field distribution, and high-precision dynamic control of the V / G ratio at the solid-liquid interface front during the entire growth process from the beginning to the end of the crystal rod is achieved, providing a key technical guarantee for the perfect single crystal growth.

[0126] Although example embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above example embodiments are merely illustrative and are not intended to limit the scope of the present application. Various changes and modifications may be made therein by those skilled in the art without departing from the scope and spirit of the present application. All such changes and modifications are intended to be included within the scope of the present application as required by the appended claims.

[0127] Similarly, it should be understood that in order to streamline the present application and aid in understanding one or more of the various application aspects, in the description of the exemplary embodiments of the present application, the various features of the present application are sometimes grouped together into a single embodiment, figure, or description thereof. However, this approach of the present application should not be interpreted as reflecting the intention that the claimed application requires more features than those explicitly recited in each claim. More precisely, as reflected in the corresponding claims, the point of the application is that the corresponding technical problem can be solved with fewer features than all the features of a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into the detailed description, with each claim itself serving as a separate embodiment of the present application.

[0128] Furthermore, those skilled in the art will appreciate that although some embodiments described herein include certain features included in other embodiments but not other features, combinations of features from different embodiments are intended to be within the scope of this application and to form different embodiments. For example, in the claims, any of the claimed embodiments may be used in any combination.

[0129] It should be noted that the above embodiments are illustrative rather than limiting of the present application, and that those skilled in the art may devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The use of the words first, second, and third, etc., does not denote any order. These words may be interpreted as designations.

Claims

1. A cooling unit, applied to a single crystal furnace, characterized in that: The cooling unit comprises: An inner cylinder and an outer cylinder are coaxially sleeved, and an annular top plate and an annular bottom plate are connected to the inner cylinder and the outer cylinder, wherein the inner cylinder, the outer cylinder, the annular top plate and the annular bottom plate together form an annular cavity; a plurality of first and second partition plates, wherein the first and second partition plates are disposed in the annular cavity, sidewalls of the first and second partition plates being connected to the inner cylinder and the outer cylinder, respectively; one end of the first partition plate being connected to the top plate, a first gap being defined between the other end of the first partition plate and the bottom plate; and one end of the second partition plate being connected to the bottom plate, a second gap being defined between the other end of the second partition plate and the top plate; The first partition plates and the second partition plates are alternately arranged along the outer circumference of the inner tube, thereby forming a serpentine refrigerant pipeline.

2. The cooling unit according to claim 1, wherein The cooling unit is used to be sleeved on the periphery of the crystal rod, and the angle between the central axis of the cooling unit and the central axis of the crystal rod is 0° to 45°.

3. A cooling device, applied to a single crystal furnace, characterized in that: The cooling device comprises: One or more cooling units according to any one of claims 1 to 2, when there are multiple cooling units, the multiple cooling units are arranged in a radial direction based on the central axis and connected by the following refrigerant pipe assembly; A refrigerant pipe assembly, the refrigerant pipe assembly includes a refrigerant inlet pipe and a refrigerant outlet pipe that are independently arranged. One or more nested refrigerant inlet channels are provided in the refrigerant inlet pipe, and each of the refrigerant inlet channels is connected to the annular cavity of each of the cooling units in a one-to-one manner. One or more nested refrigerant outflow channels are provided in the refrigerant outflow pipe, and each of the refrigerant outflow channels is connected to the annular cavity of each of the cooling units in a one-to-one manner.

4. The cooling device according to claim 3, wherein: The cooling device further comprises: A flow regulating unit, comprising one or more flow regulating valves, each of which is disposed at the inlet end of each of the refrigerant inflow channels in a one-to-one correspondence, for regulating the refrigerant flow of the corresponding cooling unit; A temperature acquisition unit, comprising one or more temperature sensors, each of which is disposed at the outlet end of each of the refrigerant outflow channels in a one-to-one correspondence, and is used to collect the outlet refrigerant temperature of the corresponding cooling unit; A control element, which is electrically connected to the flow regulating unit and the temperature collecting unit, and is configured as follows: Obtaining the outlet refrigerant temperature collected by each temperature sensor; comparing the outlet refrigerant temperature with a preset temperature curve for each stage of the crystal growth process; The opening of each flow regulating valve is controlled according to the comparison result to adjust the refrigerant flow of each cooling unit.

5. The cooling device according to claim 3, wherein: The cooling device further comprises: A flow regulating unit, comprising one or more flow regulating valves, each of which is disposed at the inlet end of each of the refrigerant inflow channels in a one-to-one correspondence, for regulating the refrigerant flow of the corresponding cooling unit; A temperature acquisition unit, comprising one or more temperature sensors, each of which is disposed in a corresponding central region of each cooling unit, for acquiring the surface temperature of the region on the crystal ingot corresponding to each cooling unit; A control element, which is electrically connected to the flow regulating unit and the temperature collecting unit, and is configured as follows: Acquiring the surface temperature collected by each of the temperature sensors; The opening of each flow regulating valve is controlled according to the surface temperature to adjust the refrigerant flow of each cooling unit.

6. The cooling device according to claim 4 or 5, characterized in that: The cooling device further comprises: Refrigerant main pipeline; One or more refrigerant branch pipes, each refrigerant inflow channel is connected to the refrigerant main pipe through a corresponding refrigerant branch pipe, and each refrigerant branch pipe is provided with a flow regulating valve.

7. The cooling device according to claim 4, wherein: The cooling device further comprises: Refrigerant return pipe; One or more return branch pipes, each refrigerant outflow channel is connected to the refrigerant return pipe through a corresponding return branch pipe, and each return branch pipe is provided with a temperature sensor.

8. The cooling device according to claim 3, wherein: There is a third gap between adjacent cooling units.

9. The cooling device according to claim 8, wherein: The cooling device further comprises: One or more groups of blocking components, wherein one group of blocking components is provided between adjacent cooling units to block the third gap; Among them, each group of the sealing components includes an inner annular sealing plate and an outer annular sealing plate that are coaxially sleeved, the inner diameter of the inner annular sealing plate is consistent with the inner diameter of the annular cavity of the cooling unit, and the outer diameter of the outer annular sealing plate is consistent with the outer diameter of the annular cavity of the cooling unit.

10. A single crystal furnace, characterized in that: The single crystal furnace comprises: a furnace body with a furnace cavity disposed therein; a crucible, disposed in the furnace chamber; The cooling device according to any one of claims 3 to 9, arranged in the furnace cavity above the crucible.

Images