A single crystal furnace main chamber and a single crystal furnace

Abstract

This utility model applies to the field of single crystal furnaces, providing a main chamber and furnace for a single crystal furnace. The main chamber includes an inner wall, an outer wall, and several baffles. A closed annular cavity is formed between the inner and outer walls. The baffles are evenly arranged circumferentially along the annular cavity. Adjacent baffles together define a flow channel that divides the annular cavity into a reciprocating continuous flow structure. The inlet and outlet of the flow channel are adjacent to each other. By setting circumferentially evenly distributed baffles in the annular cavity formed by the inner and outer walls, the flow channel is divided into a reciprocating continuous flow structure, and the inlet and outlet are adjacent to each other, effectively shortening the flow path of the cooling medium, reducing local temperature differences, improving sealing performance and heat exchange efficiency, and reducing interference with external magnetic fields, thus exhibiting significant technical advantages.

Description

Technical Field

[0001] This utility model belongs to the field of single crystal furnace technology, and particularly relates to a single crystal furnace main chamber and a single crystal furnace. Background Technology

[0002] With the rapid development of the photovoltaic industry and the increasing demand for high-purity, large-size monocrystalline silicon wafers in integrated circuits, the Czochralski method for monocrystalline silicon growth has become the mainstream preparation method. As the core equipment for realizing this process, the performance of the single crystal furnace directly affects the crystal quality, growth stability and yield. In modern high-end single crystal furnaces, in order to suppress thermal convection in the melt, reduce impurity diffusion and improve crystal uniformity, a transverse or longitudinal magnetic field is usually introduced for electromagnetic control, which is the so-called "magnetically controlled Czochralski" (MCZ). This technology has been widely used in the production of large-size silicon wafers of 6 inches and above since the end of the 20th century.

[0003] Most existing single crystal furnace main chambers adopt a double-wall structure, forming an annular cooling water channel between the inner and outer walls. The temperature of the main chamber is controlled by an external water supply system. A typical structural design places the water inlet at the upper part of the outer side of the main chamber and the water outlet at the lower part at the relatively far end. The water flow is spiral or zigzag to extend the heat exchange path.

[0004] However, while the above structure can achieve basic cooling functions, it has revealed several key problems in practical applications: First, because the inlet and outlet are located in different positions in the main chamber, the local temperature difference is large, which can easily cause uneven thermal stress in the cavity, affecting vacuum sealing and structural lifespan; Second, traditional water channels have dead zones or stagnant areas, especially at flange transition sections and corners, which are prone to gas accumulation and scaling, reducing heat exchange efficiency and increasing maintenance costs; More importantly, the external inlet / outlet pipes and their layout can interfere with the distribution of the externally applied magnetic field, causing magnetic field distortion, resulting in uneven distribution of Lorentz force in the melt, which in turn leads to defects such as interface fluctuations and oxygen and carbon segregation, seriously affecting the consistency of crystal electrical properties. Utility Model Content

[0005] The single crystal furnace main chamber and single crystal furnace provided in this embodiment of the invention aim to solve the technical problems of the existing single crystal furnace main chamber in terms of cooling uniformity, flow channel unobstructedness and magnetic field compatibility.

[0006] This utility model embodiment is implemented as follows: a main chamber for a single crystal furnace, used in a single crystal furnace, includes: Inner wall; The outer wall, and a closed annular cavity is formed between the inner wall and the outer wall; A plurality of baffles are uniformly arranged along the circumference of the annular cavity, and adjacent baffles together define a flow channel for dividing the annular cavity into a reciprocating continuous flow channel. The inlet and outlet of the flow channel are arranged adjacent to each other.

[0007] Furthermore, the main chamber of the single crystal furnace also includes a water inlet channel, one side of which is connected to the water inlet, and the other side of which is connected to a flow channel on the side away from the water inlet. The water inlet channel is isolated from the other flow channels.

[0008] Furthermore, the flow channels are arranged at intervals along the axial direction of the annular cavity, and adjacent flow channels are connected.

[0009] Furthermore, the baffles are distributed at intervals along the axial direction of the annular cavity, and the interval between two adjacent baffles is the same.

[0010] Furthermore, the main chamber of the single crystal furnace also includes: Upper flange, which is located above the main chamber of the single crystal furnace; The lower flange is located below the main chamber of the single crystal furnace. An annular sealing groove is formed on the end face of the upper flange and / or the lower flange. The bottom of the annular sealing groove is designed to be flat and smooth, and a sealing structure is provided inside the annular sealing groove.

[0011] Furthermore, the sealing structure includes at least one of a rubber sealing ring, a metal sealing ring, and a plastic sealing ring.

[0012] Furthermore, both the inlet and the outlet are located in the area close to the upper flange.

[0013] Furthermore, the main chamber of the single crystal furnace also includes a gripping assembly disposed on the outer wall. The gripping assembly is used to cooperate with the conveying assembly to realize the disassembly, assembly, and positioning of the main chamber of the single crystal furnace.

[0014] Furthermore, the gripping component includes a three-claw gripper plate, the surface of which is provided with an anti-slip structure to enhance the friction of the three-claw gripper plate.

[0015] A single crystal furnace, comprising the single crystal furnace main chamber as described in any of the preceding claims.

[0016] The beneficial effects achieved by this utility model are that by setting baffles evenly distributed in the circumferential direction in the annular cavity formed by the inner and outer walls, the flow channel is divided into a reciprocating continuous flow structure, and the inlet and outlet are set adjacent to each other, which effectively shortens the flow path of the cooling medium, reduces local temperature difference, improves sealing performance and heat exchange efficiency, and reduces interference with external magnetic fields, thus having significant technical advantages. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the main chamber of the single crystal furnace provided in this embodiment of the utility model; Figure 2 This is another schematic diagram of the main chamber of the single crystal furnace provided in this embodiment of the utility model; Figure 3 This is a schematic diagram of the structure of the single crystal furnace provided in this embodiment of the utility model. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0019] Most existing single crystal furnace main chambers adopt a double-wall structure, forming an annular cooling water channel between the inner and outer walls. The temperature of the main chamber is controlled by an external water supply system. A typical structural design places the water inlet at the upper part of the outer side of the main chamber and the water outlet at the lower part at the relatively far end. The water flow is spiral or zigzag to extend the heat exchange path.

[0020] However, while the above structure can achieve basic cooling functions, it has revealed several key problems in practical applications: First, because the inlet and outlet are located in different positions in the main chamber, the local temperature difference is large, which can easily cause uneven thermal stress in the cavity, affecting vacuum sealing and structural lifespan; Second, traditional water channels have dead zones or stagnant areas, especially at flange transition sections and corners, which are prone to gas accumulation and scaling, reducing heat exchange efficiency and increasing maintenance costs; More importantly, the external inlet / outlet pipes and their layout can interfere with the distribution of the externally applied magnetic field, causing magnetic field distortion, resulting in uneven distribution of Lorentz force in the melt, which in turn leads to defects such as interface fluctuations and oxygen and carbon segregation, seriously affecting the consistency of crystal electrical properties.

[0021] This application divides the flow channel into a reciprocating continuous flow structure by setting baffles evenly distributed in the annular cavity formed by the inner and outer walls, and setting the inlet and outlet adjacent to each other. This effectively shortens the flow path of the cooling medium, reduces local temperature difference, improves sealing performance and heat exchange efficiency, and reduces interference with external magnetic fields, which has significant technical advantages.

[0022] Example 1 Please see Figures 1 to 2 The present invention is implemented as follows: a single crystal furnace main chamber 100, used in a single crystal furnace 1000, comprises: Inner wall 101; An outer wall 102 and an inner wall 101 form a closed annular cavity 103 between the outer wall 102 and the inner wall 101. A plurality of baffles 104 are evenly arranged along the circumference of the annular cavity 103. Adjacent baffles 104 together define a flow channel 105 for dividing the annular cavity 103 into a reciprocating continuous flow. The inlet 20 and outlet 30 of the flow channel 105 are arranged adjacent to each other.

[0023] In this embodiment, the baffle 104 refers to the flow guiding component disposed in the annular cavity 103. Specifically, it can be implemented by metal partitions with equal spacing, the thickness of which is adapted to the width of the cavity, and is used to guide the direction of water flow. The flow channel 105 refers to an independent flow channel formed by adjacent baffles 104 along the axial direction of the annular cavity 103. Specifically, it can be achieved by a staggered arrangement of baffles 104, with adjacent flow channels connected end to end to form a continuous path. The adjacent arrangement of the inlet 20 and the outlet 30 means that they are located in the same axial plane, specifically in the top area of ​​the annular cavity 103 near the upper flange 40.

[0024] Furthermore, after the cooling medium (cold water) enters through the inlet 20, it flows through the inlet channel 106 into the flow channel 105, and then flows sequentially through each flow channel 105 in the circumferential direction. The baffle plate 104 forces the water flow to flow back and forth between adjacent channels. Since the inlet and outlet 30 are arranged adjacently, the water flow is discharged directly from the adjacent position after completing the circulation of the entire annular cavity 103. This design makes the water flow path form a closed loop, avoiding the temperature gradient caused by the arrangement at the far end. At the same time, the uniform distribution of the baffle plate 104 eliminates the stagnant area of ​​the flange transition section. For example, when the water flows in from the left side of the first baffle plate, the right side of the second baffle plate forms a return channel, ensuring that the water flow covers the entire annular cross section.

[0025] This configuration effectively balances the temperature distribution on the wall of the main chamber 100 of the single crystal furnace, eliminates the problem of scale buildup caused by cooling dead zones, and reduces the risk of magnetic field distortion by simplifying the external connection structure. The continuous back-and-forth flow of water between adjacent baffles 104 improves heat exchange efficiency, and the adjacent layout of the inlet and outlet 30 shortens the residence time of the cooling medium, thereby maintaining a more stable thermal environment.

[0026] In this embodiment, there are ten baffles 104. In other embodiments, the number of baffles 104 can be 11, 12, 13, etc. The specific number can be designed according to the actual situation and is not limited here.

[0027] Example 2 Please see Figure 1 Furthermore, the main chamber 100 of the single crystal furnace also includes a water inlet channel 106. One side of the water inlet channel 106 is connected to the water inlet 20, and the other side of the water inlet channel 106 is connected to a flow channel 105 on the side away from the water inlet 20. The water inlet channel 106 is isolated from the other flow channels 105.

[0028] Specifically, the water inlet channel 106 refers to an independent channel connecting the water inlet 20 and the distal flow channel 105. It can be implemented by a longitudinal guide channel opened on the outside of the annular cavity 103, and its cross-sectional shape can be designed as rectangular or trapezoidal. The partition refers to separating the water inlet channel 106 from other flow channels 105 by welding or integral molding. Specifically, it can be achieved by using stainless steel partitions or sealing strips to fill the gaps, thereby ensuring that the water flows only along the preset path.

[0029] After entering through the inlet 20, the cooling water is first directly delivered to the side of the annular cavity 103 away from the inlet 20 through the inlet channel 106. Then it flows through each layer of flow channels 105 to form a circulation. Since the inlet channel 106 is completely isolated from other flow channels 105, the water flow is forced to flow in layers along the axial direction of the annular cavity 103, avoiding the local eddies generated by the traditional spiral flow. This directional flow design allows the cooling water to evenly cover the surface of the main inner wall 101, while eliminating the stagnant area at the flange connection.

[0030] This configuration allows the cooling medium to be directly delivered to the far end via an independent water inlet channel 106, resulting in a more balanced water pressure distribution in each flow channel 105. In addition, it effectively eliminates localized thermal stress concentration caused by uneven axial cooling in the main chamber 100 of the single crystal furnace, reduces the risk of leakage caused by temperature deformation of the flange sealing surface, and the consistency of water flow velocity in the flow channel 105 reduces the probability of scale buildup and extends the maintenance cycle. The directional flow structure also avoids the influence of external pipes on the magnetic control system, which is conducive to maintaining a stable distribution of Lorentz force on the melt surface.

[0031] Example 3 Please refer to it again. Figure 1 Furthermore, the flow channels 105 are arranged at intervals along the axial direction of the annular cavity 103, and two adjacent flow channels 105 are connected.

[0032] In this embodiment, the axially spaced arrangement of the flow channels 105 means that multiple independent channels are arranged in layers along the height direction of the annular cavity 103. The layered design can guide the cooling water to form a multi-level flow path in the axial direction. The connection between adjacent flow channels 105 means that one side of the vertically adjacent channels is connected. The connection design allows the water flow to switch the flow direction between adjacent channels.

[0033] Specifically, after the cooling water enters the lowest flow channel 105 from the inlet 20, it flows circumferentially to the end, then enters the next adjacent channel and flows in the opposite direction, circulating in sequence until it is discharged from the outlet 30. This combination of axial layering and adjacent interconnection forces the water flow to form a continuous serpentine return path within the annular cavity 103, which not only prolongs the contact time between the cooling water and the cavity wall, but also avoids the local stagnation caused by traditional spiral flow.

[0034] This configuration achieves uniform distribution of cooling water flow within the annular cavity 103, reduces thermal stress concentration caused by temperature gradients, reduces the risk of scaling by eliminating flow dead zones, and avoids interference from external pipes on the magnetic field distribution, thereby improving the stability of the monocrystalline silicon growth process.

[0035] Example 4 Furthermore, the baffles 104 are distributed at intervals along the axial direction of the annular cavity 103, and the interval between two adjacent baffles 104 is the same.

[0036] In this embodiment, axial spacing distribution refers to layered arrangement along the height direction of the main chamber 100 of the single crystal furnace. Specifically, the position of the baffle 104 can be fixed by setting a support structure in the annular cavity 103 to ensure that each layer of baffle 104 is parallel to the horizontal plane. The same spacing means that the vertical distance between adjacent baffles 104 remains constant. Specifically, the baffle 104 bracket can be processed using standardized molds, and equidistant assembly can be achieved through mechanical positioning.

[0037] Specifically, the baffles 104 are arranged at equal intervals in the vertical direction within the annular cavity 103, forming multiple parallel flow guide layers. After the cooling water enters from the inlet 20, it flows through the water channels defined by each layer of baffles 104 in sequence. The flow direction between adjacent layers is switched through the flow guide gaps at the edges of the baffles 104. Since the spacing of the baffles 104 is consistent, the flow velocity and pressure distribution of the water in each water channel tend to be balanced, avoiding turbulence or stagnation caused by abrupt changes in spacing in local areas.

[0038] Furthermore, the uniform spacing of the baffles 104 can avoid the transmission of vibration caused by water flow impact, and enhance the structural stability of the main chamber 100 of the single crystal furnace. In addition, the standardized spacing design simplifies the processing and assembly process of the baffles 104, which helps to reduce manufacturing costs and improve product consistency.

[0039] Example 5 Please see Figures 1 to 2 Furthermore, the main chamber 100 of the single crystal furnace also includes: Upper flange 40 is located above the main chamber 100 of the single crystal furnace; The lower flange 50 is located below the main chamber 100 of the single crystal furnace. An annular sealing groove (not shown in the figure) is formed on the end face of the upper flange 40 and / or the lower flange 50. The bottom of the annular sealing groove is flat and smooth, and a sealing structure (not shown in the figure) is provided inside the annular sealing groove.

[0040] In this embodiment, the upper flange 40 refers to the annular pressure-bearing component installed on the top of the main chamber 100 of the single crystal furnace for connecting external components. Specifically, it can be made of forged stainless steel material, and its end face is arranged perpendicular to the axis of the main chamber 100 of the single crystal furnace to achieve the flatness of the sealing surface. The lower flange 50 refers to the annular support component installed at the bottom of the main chamber 100 of the single crystal furnace to fix the position of the main chamber 100 of the single crystal furnace. Specifically, it can be connected to the furnace body base by bolts, and its end face machining accuracy needs to match that of the upper flange 40. An annular sealing groove refers to a groove structure that is continuously opened along the circumference of the flange end face. It can be formed by CNC milling. The surface roughness of the groove bottom is controlled below Ra0.8 to ensure the fit of the sealing structure. Specifically, the upper flange 40 and the lower flange 50 can be fixed to both ends of the shell of the main chamber 100 of the single crystal furnace by welding or bolting. When the flange end face is processed, a precision grinding process is used to ensure that the flatness error is less than 0.05 mm. The annular sealing groove is continuously distributed along the outer edge of the flange end face. After the bottom of the groove is polished, it forms a surface contact with the sealing structure. During the assembly process, the sealing structure is pre-compressed and installed in the sealing groove. When the flange is fastened to the adjacent parts by bolts, the sealing structure produces uniform radial deformation to eliminate the assembly gap.

[0041] This design, through the combination of annular sealing groove and sealing structure, can maintain stable contact pressure under high-temperature conditions, avoiding separation of the sealing surface due to thermal expansion. At the same time, the flat groove bottom structure can prevent permanent deformation caused by local excessive compression of the seal.

[0042] Example 6 Furthermore, the sealing structure includes at least one of a rubber sealing ring, a metal sealing ring, and a plastic sealing ring.

[0043] Specifically, a rubber sealing ring refers to a ring-shaped sealing element made of elastic rubber material, which can be made of nitrile rubber or fluororubber, and uses the elastic deformation of the material to compensate for the gap at the flange end face. Metal sealing rings are sealing rings made of ductile metal materials, specifically copper alloys or stainless steel, which fill the microscopic uneven areas of the sealing groove through plastic deformation. Plastic sealing rings are sealing elements molded from high molecular polymers, specifically polytetrafluoroethylene or polyimide, which reduce the frictional resistance of flange assembly by relying on the self-lubricating properties of the material.

[0044] Furthermore, under the condition that the bottom of the annular sealing groove is flat and smooth, the rubber sealing ring can meet the sealing requirements of the normal temperature range, the metal sealing ring is suitable for vacuum sealing in high temperature ranges, and the plastic sealing ring is for working conditions with chemically corrosive media. When the end faces of the upper flange 40 and / or the lower flange 50 undergo slight displacement due to thermal expansion, the sealing rings of different materials maintain the contact pressure through elastic deformation or plastic deformation, preventing cooling water from leaking out of the annular cavity 103. By using sealing rings of different materials in combination, dynamic sealing compensation can be achieved in both axial and radial dimensions.

[0045] It should be noted that in other embodiments, the sealing structure may also use sealing ring types other than those described above. The specific design can be made according to the actual situation and is not limited here.

[0046] Example 7 Please see Figures 1 to 2 Furthermore, both the inlet 20 and the outlet 30 are located in the area close to the upper flange 40.

[0047] In this embodiment, by concentrating the inlet 20 and outlet 30 in the area near the upper flange 40, the cooling medium enters the annular cavity 103 from the same direction and flows sequentially through each cavity layer along the flow channel 105 formed by the baffle 104, and finally exits from the adjacent outlet 30. Since the inlet and outlet 30 are located at the top of the main chamber, a flow path from bottom to top is naturally formed during the continuous delivery of the cooling medium, avoiding the local stagnation caused by the traditional far-end layout. At the same time, this layout allows the external water supply pipeline to be concentrated at the top of the single crystal furnace main chamber 100, reducing the interference of lateral pipelines on the magnetic field distribution.

[0048] Example 8 Please see Figures 1 to 2 Furthermore, the main chamber 100 of the single crystal furnace also includes a gripping component 60, which is disposed on the outer wall 102. The gripping component 60 is used to cooperate with the conveying component to realize the disassembly, assembly and positioning of the main chamber 100 of the single crystal furnace.

[0049] Furthermore, the gripping component 60 includes a three-claw gripper with an anti-slip structure on its surface to enhance the friction of the gripper.

[0050] The gripping component 60 refers to a mechanical clamping device that is fixedly connected to the outer wall 102. It can be implemented by welding or bolting. It is used to provide a stable force support point during transportation. The three-jaw gripper refers to a rigid structural component with three symmetrically distributed gripping arms. It can be made by casting high-strength alloy steel. It forms a self-centering clamping effect through three-point contact.

[0051] Specifically, the anti-slip structure refers to the textured layer attached to the clamping contact surface, which can be achieved by knurling or rubber coating, thereby increasing the surface friction coefficient to prevent slippage.

[0052] Furthermore, the gripping component 60 forms a rigid connection with the slot of the transport component (transport robot arm) through the three-jaw gripper. The anti-slip structure generates a micro-interlocking effect on the contact surface. When the transport component applies a vertical lifting force, the symmetrical distribution characteristics of the three-jaw gripper cause the center of gravity of the main chamber to be automatically corrected. The installation position set on the outer wall 102 avoids the magnetic field sensitive area inside the main chamber. During the disassembly and assembly process, the opening and closing angle of the three-jaw gripper is controlled by the limiting device to ensure the docking accuracy with the transport component.

[0053] The above settings improve the positioning accuracy and handling stability of the main chamber 100 of the single crystal furnace during disassembly and assembly, reduce the risk of equipment collision due to grip failure, and reduce the operation time loss caused by repeated position adjustments. The structure is simple and easy to implement.

[0054] Example 9 Please see Figure 3 A single crystal furnace 1000, which includes the single crystal furnace main chamber 100 of any of the above.

[0055] The beneficial effects achieved by this utility model are that by setting baffles 104 evenly distributed in the circumferential direction in the annular cavity 103 formed by the inner wall 101 and the outer wall 102, the flow channel 105 is divided into a reciprocating continuous flow structure, and the inlet 20 and outlet 30 are arranged adjacent to each other, the flow path of the cooling medium is effectively shortened, the local temperature difference is reduced, the sealing performance and heat exchange efficiency are improved, and the interference to the external magnetic field is reduced, which has significant technical advantages.

[0056] It is understood that those skilled in the art can combine various implementation methods in the above embodiments under the guidance of the above examples to obtain technical solutions with multiple implementation methods.

[0057] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A main chamber for a single crystal furnace, used in a single crystal furnace, characterized in that, It includes: Inner wall; The outer wall, and a closed annular cavity is formed between the inner wall and the outer wall; A plurality of baffles are uniformly arranged along the circumference of the annular cavity, and adjacent baffles together define a flow channel for dividing the annular cavity into a reciprocating continuous flow channel. The inlet and outlet of the flow channel are arranged adjacent to each other.

2. The main chamber of the single crystal furnace as described in claim 1, characterized in that, The main chamber of the single crystal furnace also includes a water inlet channel. One side of the water inlet channel is connected to the water inlet, and the other side of the water inlet channel is connected to a flow channel on the side away from the water inlet. The water inlet channel is isolated from the other flow channels.

3. The main chamber of the single crystal furnace as described in claim 2, characterized in that, The water channels are arranged at intervals along the axial direction of the annular cavity, and adjacent water channels are connected.

4. The main chamber of the single crystal furnace as described in claim 3, characterized in that, The baffles are distributed at intervals along the axial direction of the annular cavity, and the interval between two adjacent baffles is the same.

5. The main chamber of the single crystal furnace as described in claim 1, characterized in that, The main chamber of the single crystal furnace also includes: Upper flange, which is located above the main chamber of the single crystal furnace; The lower flange is located below the main chamber of the single crystal furnace. An annular sealing groove is formed on the end face of the upper flange and / or the lower flange. The bottom of the annular sealing groove is designed to be flat and smooth, and a sealing structure is provided inside the annular sealing groove.

6. The main chamber of the single crystal furnace as described in claim 5, characterized in that, The sealing structure includes at least one of a rubber sealing ring, a metal sealing ring, and a plastic sealing ring.

7. The main chamber of the single crystal furnace as described in claim 6, characterized in that, Both the inlet and the outlet are located in the area near the upper flange.

8. The main chamber of the single crystal furnace as described in claim 7, characterized in that, The main chamber of the single crystal furnace also includes a gripping component, which is disposed on the outer wall and is used to cooperate with the conveying component to realize the disassembly, assembly and positioning of the main chamber of the single crystal furnace.

9. The main chamber of the single crystal furnace as described in claim 8, characterized in that, The gripping assembly includes a three-claw gripper plate, the surface of which is provided with an anti-slip structure to enhance the friction of the gripper plate.

10. A single crystal furnace, characterized in that, It includes the main chamber of the single crystal furnace as described in any one of claims 1-9.

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