Single crystal thermal field structure and single crystal furnace

Abstract

The utility model relates to the technical field of single crystal silicon manufacturing, in particular to a single crystal thermal field structure and a single crystal furnace, the single crystal thermal field structure comprises a supporting rod disc and a bottom heater, the bottom heater is arranged in the single crystal furnace, and a receding hole is formed in the bottom heater; the supporting rod disc is used for supporting the crucible body and located on the bottom heater. The lower end of the supporting rod disc can be located in the receding hole. The receding hole is formed in the bottom heater, so that the lower end of the supporting rod disc can be located in the receding hole, the lower limit of the supporting rod disc is further lowered, the whole crucible body can be lowered to be lower, the space between the lower edge of the guide cylinder and the liquid level of the crucible body is larger during feeding, and the feeding amount of a single cylinder can be larger; the total feeding measuring cylinder number is reduced, so that the single-time feeding rate is improved, the productivity is released to the maximum extent, and the production efficiency of equipment is effectively improved.

Description

Technical Field

[0001] This application relates to the field of monocrystalline silicon manufacturing technology, and in particular to a monocrystalline thermal field structure and a monocrystalline furnace. Background Technology

[0002] The CZ (Czochralski) Czochralski method for producing single crystals mainly involves heating polycrystalline silicon in a quartz crucible using a graphite heater to melt it and maintain a temperature slightly above the melting point of silicon. Under the protection of inert argon gas, the crystal growth is completed through steps such as crystal pulling, shoulder formation, shoulder rotation, equal diameter shaping, tailing, and crystal removal.

[0003] The hot zone of a single-crystal furnace consists of hot zone components and insulation materials. Among single-crystal silicon wafer manufacturers, the commonly used hot zone diameter is around 36 inches. The key to increasing the material feed rate lies in increasing the height of the hot zone. However, increasing the hot zone height requires technical modifications to major components such as the insulation tank and heaters, which are relatively costly and have varying impacts on crystal pulling. Therefore, how to increase the material feed rate to improve equipment production efficiency while reducing energy consumption and production costs has become a pressing technical problem in this field.

[0004] It should be noted that the above content is not necessarily prior art, nor is it intended to limit the scope of patent protection of this application. Utility Model Content

[0005] This application provides a single-crystal thermal field structure and a single-crystal furnace to solve or alleviate one or more of the technical problems mentioned above.

[0006] As a first aspect of the embodiments of this application, the embodiments of this application provide a single-crystal thermal field structure, including:

[0007] A bottom heater is provided inside the single crystal furnace, and the bottom heater is provided with a clearance hole;

[0008] A support rod disk is used to support the crucible body, and the support rod disk is located on the bottom heater;

[0009] The lower end of the support rod disc can be located in the clearance hole.

[0010] Optionally, an insulation space is formed between the bottom heater and the bottom of the single crystal furnace;

[0011] The single crystal thermal field structure further includes a bottom heater electrode; wherein, the bottom heater electrode is used to be disposed at the bottom of the single crystal furnace, and the bottom heater electrode extends vertically upward and is electrically connected to the bottom heater;

[0012] The bottom heater electrode is provided with an extended electrode section, the length of which is not greater than the thickness of the support rod disk.

[0013] Optionally, a protective plate is provided on the side of the bottom heater away from the crucible body, and the distance between the protective plate and the bottom heater is 20~30mm.

[0014] Optionally, the protective plate is used to be placed inside the single crystal furnace, and a heat-insulating felt is provided between the protective plate and the bottom of the single crystal furnace;

[0015] A sub-insulating felt is provided between the insulating felt and the protective plate pressing sheet, and the thickness of the sub-insulating felt can be the same as the length of the extended electrode section.

[0016] Optionally, the diameter of the support rod disk is R1, the diameter of the relief hole is R2, and the distance between the support rod disk and the inner wall forming the relief hole is (R1-R2) / 2.

[0017] Optionally, when the lower end of the support rod disc is located in the clearance hole, the distance between the upper surface of the support rod disc and the bottom heater is 20~30mm.

[0018] Optionally, when the lower end of the support rod disk is located in the relief hole, the distance between the edge of the support rod disk and the inner wall forming the relief hole is at least 20 mm.

[0019] Optionally, the support rod disc is used to connect the support rod shaft, and one end of the support rod shaft passes through the clearance hole and connects to the support rod disc;

[0020] The support rod disc supports the crucible body via a pot support.

[0021] Optionally, the bottom heater includes a first heating plate and a second heating plate, the first heating plate being connected to the second heating plate via a first heating wire and a second heating wire; the clearance hole is formed between the first heating wire and the second heating wire.

[0022] As a second aspect of the embodiments of this application, this application provides a single crystal furnace, including:

[0023] Single crystal furnace chamber;

[0024] The above-mentioned single-crystal thermal field structure;

[0025] The single-crystal thermal field structure is disposed inside the single-crystal furnace chamber.

[0026] The embodiments of this application employing the above-described technical solution may have the following advantages:

[0027] By setting a clearance hole on the bottom heater, the lower end of the support rod disk can be located in the clearance hole, further reducing the lower limit of the support rod disk. This allows the crucible body to be lowered further, resulting in a larger space between the lower edge of the guide tube and the liquid surface of the crucible body during feeding. This allows for a larger feeding volume per tube, reducing the total number of feeding cycles and thus improving the single feeding rate, maximizing production capacity, and effectively improving the equipment's production efficiency. Attached Figure Description

[0028] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in this application and should not be construed as limiting the scope of this application.

[0029] Figure 1 This is a partial structural schematic diagram of the single-crystal thermal field structure provided in the embodiments of this application.

[0030] Figure 2 This is a cross-sectional view of a portion of the single-crystal thermal field structure provided in the embodiments of this application.

[0031] Figure 3 This is a partial structural schematic diagram of the single-crystal thermal field structure provided in the embodiments of this application, showing the support rod disk and the bottom heater.

[0032] Explanation of reference numerals in the attached figures:

[0033] 1. Support rod disc; 11. Support rod shaft; 2. Bottom heater; 21. Clearance hole; 22. First heating plate; 23. Second heating plate; 24. First heating wire; 25. Second heating wire; 3. Crucible body; 31. Pot support; 4. Bottom heater electrode; 41. Extended electrode section; 5. Protective plate pressing sheet; 51. Insulation felt; 52. Sub-insulation felt. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other. The application will now be described in detail with reference to the accompanying drawings and embodiments.

[0035] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0036] Exemplary embodiments according to this application will now be described in more detail with reference to the accompanying drawings. It should be understood that these exemplary embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein.

[0037] like Figures 1-3 As shown, in a first aspect, embodiments of this application can provide a single-crystal thermal field structure, which may include:

[0038] Bottom heater 2 is installed inside the single crystal furnace, and a clearance hole 21 is provided in the bottom heater 2;

[0039] The support rod disk 1 is used to support the crucible body 3, and the support rod disk 1 is located on the bottom heater 2;

[0040] The lower end of the support rod disc 1 can be located in the relief hole 21.

[0041] In this embodiment, by providing a clearance hole 21 on the bottom heater 2, the lower end of the support rod disk 1 can be located in the clearance hole 21, further reducing the lower limit of the support rod disk 1. This allows the crucible body 3 to be lowered further, resulting in a larger space between the lower edge of the guide tube and the liquid surface of the crucible body 3 during feeding. This allows for a larger single-tube feeding amount, reducing the total number of feeding cycles, thereby increasing the single-feeding rate, maximizing production capacity, and effectively improving the equipment's production efficiency.

[0042] It should be noted that, because the lower limit of the support rod disk 1 is lower, there is a larger space between the lower edge of the guide tube and the liquid surface of the crucible body 3 when feeding, that is, a larger feeding space, which reduces the risk of material jamming, and consequently reduces the risk of the guide tube being damaged by the material block, the damage rate decreases, and the feeding and melting process is smoother.

[0043] It should be noted that the heating device in the hot zone structure generally includes a main heater and a bottom heater 2, with the main heater positioned around the crucible body 3. In this embodiment, without altering other hot zones, since the lower end of the support rod disk 1 can be located within the clearance hole 21 (i.e., the lower limit of the support rod disk 1 is lower), the full-crate feed rate can be increased by increasing the height of the crucible body 3, thereby maximizing production capacity. Furthermore, with the increased height of the crucible body 3, the distance between the main heater and the bottom of the crucible body 3 will be greater, reducing the thermal radiation received by the bottom of the crucible body 3 from the main heater. This reduces the amount of oxygen atoms released from the inner wall of the crucible body 3 into the molten silicon, thereby improving the oxygen content of the crystal rod and enhancing its quality. It should be further noted that the oxygen in the crystal rod mainly originates from the silicon dioxide in the quartz crucible body 3. Silicon and silicon dioxide react to produce silicon monoxide; most of the silicon monoxide volatilizes, while a small portion condenses into the crystal rod, thus affecting its quality. Therefore, the embodiments of this application can minimize the problem of needing to make technical modifications again after batch installation due to poor crystal formation, high oxygen content, or high power consumption caused by batch-designed thermal field structures, thereby reducing the loss of a large amount of manpower, material resources, financial resources, and production capacity.

[0044] In an optional embodiment, a heat-insulating space is formed between the bottom heater 2 and the bottom of the single crystal furnace; the single crystal thermal field structure also includes a bottom heater electrode 4; wherein, the bottom heater electrode 4 is used to be disposed at the bottom of the single crystal furnace, and the bottom heater electrode 4 extends vertically upward and is electrically connected to the bottom heater 2; wherein, the bottom heater electrode 4 is provided with an extended electrode section 41, the length of which is not greater than the thickness of the support rod disk 1.

[0045] In this embodiment, when the support rod disk 1 and the thermal field remain constant, it is necessary to correct the lower limit of the support rod disk 1 by raising the bottom heater electrode 4. In this embodiment, the length of the original bottom heater electrode 4 is increased by setting an extended electrode section 41, that is, the absolute position of the original bottom heater electrode 4 is raised, so the position of the bottom heater 2 is raised synchronously, increasing the absolute height of the bottom heater 2 relative to the bottom of the single crystal furnace. This allows for increased insulation thickness within the single crystal furnace, reducing heat loss and saving energy. Furthermore, by setting the extended electrode section 41, that is, raising the absolute position of the original bottom heater electrode 4, the bottom heater 2 is closer to the bottom of the crucible body 3 when melting at the lower limit. Therefore, the heat radiation loss of the bottom heater 2 is less, and the heating efficiency of the bottom of the crucible body 3 is higher, thereby improving the melting efficiency.

[0046] It should be noted that in conventional technology, a safe distance must be maintained between the bottom heater 2 and the support rod disc 1 to prevent a dangerous accident of short circuit and arcing when the bottom heater 2 is energized. Therefore, the distance between the lower edge of the support rod disc 1 and the upper edge of the bottom heater 2 is the safe distance in conventional technology. However, in this embodiment, since the lower end of the support rod disc 1 can be located in the clearance hole 21, the distance between the upper edge of the support rod disc 1 and the upper edge of the bottom heater 2 is the safe distance in this application (the same as the safe distance height in conventional technology). After the extended electrode section 41 is installed, it is necessary to confirm the lower limit of the support rod disc 1 (i.e., the lower end of the support rod disc 1 is located in the clearance hole 21, and its upper edge maintains a safe distance from the bottom heater 2). At this time, it is necessary to correct the lower limit of the support rod disc 1 by raising the position of the bottom heater 2. The maximum raising distance of the bottom heater 2 is the same as that of the extended electrode section 41, that is, it can be raised by a distance not greater than the thickness of the support rod disc 1.

[0047] In an optional embodiment, a protective plate 5 is provided on the side of the bottom heater 2 away from the crucible body 3, and the distance between the protective plate 5 and the bottom heater 2 is 20~30mm. The distance between the protective plate 5 and the bottom heater 2 is 20~30mm, which is a safe distance to prevent a dangerous accident caused by a short circuit and arcing when the bottom heater 2 is energized.

[0048] In an optional embodiment, the protective plate 5 is used to be placed inside the single crystal furnace, and a heat insulation felt 51 is provided between the protective plate 5 and the bottom of the single crystal furnace; a sub-heat insulation felt 52 is provided between the heat insulation felt 51 and the protective plate 5, and the thickness of the sub-heat insulation felt 52 can be the same as the length of the extended electrode section 41.

[0049] In this embodiment, when the absolute height of the support rod disk 1 from the bottom of the single crystal furnace is consistent with that of the conventional hot field, an extended electrode section 41 needs to be set on the bottom heater electrode 4 so that the bottom heater 2 can be raised by a height not greater than the thickness of the support rod disk 1. Then, the thickness of the insulation structure at the bottom of the single crystal furnace can be increased by setting the sub-insulation felt 52, thereby reducing the loss of heat through the bottom of the single crystal furnace and reducing the crystal pulling power consumption.

[0050] In an optional embodiment, the diameter of the support rod disc 1 is R1, the diameter of the clearance hole 21 is R2, and the distance between the support rod disc 1 and the inner wall forming the clearance hole 21 is (R1-R2) / 2. When the lower end of the support rod disc 1 is located in the clearance hole 21, the distance between the support rod disc 1 and the inner wall forming the clearance hole 21 is a safe distance in the horizontal direction between the bottom heater 2 and the support rod disc 1, so as to ensure that the support rod disc 1 does not mechanically collide with the bottom heater 2 during parallel installation and use, and also avoids the problem of short circuit and arcing between the bottom heater 2 and the support rod disc 1 when energized.

[0051] In an optional embodiment, when the lower end of the support rod disc 1 is located in the clearance hole 21, the distance between the upper surface of the support rod disc 1 and the bottom heater 2 is 20~30mm. This distance is a safety distance to prevent a dangerous accident caused by a short circuit and arcing after the bottom heater 2 is energized.

[0052] In an optional embodiment, when the lower end of the support rod disk 1 is located in the relief hole 21, the distance between the edge of the support rod disk 1 and the inner wall forming the relief hole 21 is at least 20 mm. This distance is a safety distance to prevent short circuit and arcing between the bottom heater 2 and the support rod disk 1 after the bottom heater 2 is energized.

[0053] In an optional embodiment, the support rod disc 1 is used to connect the support rod shaft 11, with one end of the support rod shaft 11 passing through the clearance hole 21 and connecting to the support rod disc 1; the support rod disc 1 supports the crucible body 3 via the pot support 31. The support rod shaft 11 can drive the support rod disc 1 to achieve lower limit adjustment, while the pot support 31 can further support the crucible body 3, effectively relieving the load-bearing pressure on the support rod shaft 11 and the support rod disc 1, increasing the load-bearing area of ​​the crucible body 3, thereby improving the support stability of the crucible body 3.

[0054] In an optional embodiment, the bottom heater 2 includes a first heating plate 22 and a second heating plate 23. The first heating plate 22 is connected to the second heating plate 23 via a first heating wire 24 and a second heating wire 25. A clearance hole 21 is formed between the first heating wire 24 and the second heating wire 25. The clearance hole 21 formed between the first heating wire 24 and the second heating wire 25 allows the lower end of the support rod disk 1 to be located in the clearance hole 21, thereby lowering the lower limit of the support rod disk 1.

[0055] Secondly, embodiments of this application may provide a single crystal furnace, which may include:

[0056] Single crystal furnace chamber;

[0057] The single-crystal thermal field structure of any of the above embodiments;

[0058] The single-crystal thermal field structure is set inside the single-crystal furnace chamber.

[0059] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0060] For ease of description, directional terms such as "front, back, up, down, left, right," "horizontal, vertical, horizontal," and "top, bottom" generally indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. These terms are used solely for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the scope of protection of this application. The directional terms "inner" and "outer" refer to the inner or outer contours relative to the components themselves. For example, if a device in the drawings is inverted, a device described as "above" or "on top of" other devices or structures will subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein are interpreted accordingly.

[0061] Unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0062] Unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0063] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0064] It should also be noted that the terms "one embodiment," "another embodiment," or "embodiment" used in this specification refer to specific features, structures, or characteristics described in connection with that embodiment, which are included in at least one embodiment described in the general description of this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in connection with any embodiment, the intention is to suggest that implementing such a feature, structure, or characteristic in conjunction with other embodiments also falls within the scope of this application.

[0065] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0066] It should also be noted that the above are merely preferred embodiments of this application and do not limit the scope of patent protection of this application. Any equivalent structural or procedural changes made using the content of this application’s specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of this application.

Claims

1. A single crystal hot field structure, characterized by, The single crystal heat field structure comprises a bottom heater (2) arranged in a single crystal furnace, wherein a position-allowing hole (21) is arranged in the bottom heater (2); a supporting rod disc (1) for supporting a crucible main body (3) is arranged on the bottom heater (2); and the lower end of the supporting rod disc (1) is arranged in the position-allowing hole (21). A heat preservation space is formed between the bottom heater (2) and the bottom of the single crystal furnace. The single crystal heat field structure further comprises a bottom heater electrode (4); wherein the bottom heater electrode (4) is arranged on the bottom of the single crystal furnace, and the bottom heater electrode (4) is vertically upwardly extended and electrically connected with the bottom heater (2). The bottom heater electrode (4) is provided with an extended electrode segment (41), and the length of the extended electrode segment (41) is not greater than the thickness of the supporting rod disc (1).

2. The single-crystal hot field structure of claim 1, wherein, The bottom heater (2) is provided with a guard disc pressing plate (5) on the side away from the crucible main body (3), and the distance between the guard disc pressing plate (5) and the bottom heater (2) is 20-30 mm. The guard disc pressing plate (5) is arranged in the single crystal furnace, and a heat preservation felt (51) is arranged between the guard disc pressing plate (5) and the bottom of the single crystal furnace. A sub heat preservation felt (52) is arranged between the heat preservation felt (51) and the guard disc pressing plate (5), and the thickness of the sub heat preservation felt (52) is the same as the length of the extended electrode segment (41). The diameter of the supporting rod disc (1) is R1, the diameter of the position-allowing hole (21) is R2, and the distance between the supporting rod disc (1) and the inner wall forming the position-allowing hole (21) is (R1-R2) / 2. When the lower end of the supporting rod disc (1) is arranged in the position-allowing hole (21), the distance between the upper surface of the supporting rod disc (1) and the bottom heater (2) is 20-30 mm. When the lower end of the supporting rod disc (1) is arranged in the position-allowing hole (21), the distance between the edge of the supporting rod disc (1) and the inner wall forming the position-allowing hole (21) is at least 20 mm. The supporting rod disc (1) is connected with a supporting rod shaft (11), one end of the supporting rod shaft (11) is connected with the supporting rod disc (1) through the position-allowing hole (21); and the crucible main body (3) is supported by a pot support (31). The diameter of the supporting rod disc (1) is R1, the diameter of the position-allowing hole (21) is R2, and the distance between the supporting rod disc (1) and the inner wall forming the position-allowing hole (21) is (R1-R2) / 2. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The bottom heater (2) comprises a first heating plate (22) and a second heating plate (23), the first heating plate (22) is connected with the second heating plate (23) through a first heating wire (24) and a second heating wire (25); the first heating wire (24) and the second heating wire (25) enclose the accommodation hole (21).

10. A single crystal furnace characterized by comprising: Comprise: A single crystal furnace chamber; The single crystal thermal field structure of any one of claims 1 to 9; The single crystal thermal field structure is arranged in the single crystal furnace chamber.

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