Heat insulation thermal field and single crystal furnace

Abstract

A heat insulation thermal field and a single crystal furnace. The heat insulation thermal field comprises a heat insulation cylinder and a second heater, wherein the second heater is arranged in the heat insulation cylinder, the second heater comprises a second heater body, the second heater is a bottom heater, a cylinder body of the heat insulation cylinder is provided with a clearance space, and at least part of the second heater body is located in the clearance space. During crystal pulling processes, the present application can avoid heat in thermal field environments from being lost via holes in furnace bottom plates, thus reducing heat loss, and reducing the power consumption of crystal pulling.

Description

A heat preservation thermal field and single crystal furnace

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application No. 202322195650.3, filed with the Patent Office of China on August 15, 2023, entitled “A Thermal Field for Insulating a Single Crystal Furnace and a Thermal Field for a Single Crystal Furnace,” the entire contents of which are incorporated herein by reference. This application claims priority to Chinese patent application No. 202420266778.6, filed with the Patent Office of China on February 2, 2024, entitled “A Thermal Field for Insulating a Single Crystal Furnace and a Thermal Field for a Single Crystal Furnace,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] The application relates to the field of crystal pulling technology, and in particular to a heat preservation thermal field and a single crystal furnace. Background Art

[0004] Existing single crystal furnaces typically feature a primary heater and secondary heaters. The furnace floor typically has openings for the heating electrodes of the primary and secondary heaters. However, during the crystal pulling process, some heat from the thermal field is transferred longitudinally to the furnace floor and dissipated through the openings in the floor or insulation panels. This can lead to heat loss and increased power consumption during crystal pulling.

[0005] Application Contents

[0006] In view of the above problems, an application is made to provide a heat preservation thermal field and a single crystal furnace that overcome the above problems or at least partially solve the above problems.

[0007] In order to solve the above problems, in a first aspect, the present application provides a heat preservation thermal field, which includes a heat preservation cylinder and a second heater; wherein,

[0008] The second heater is arranged in the heat-insulating cylinder; a refuge space for at least partially avoiding the second heater is provided on the cylinder body of the heat-insulating cylinder; the second heater is a bottom heater.

[0009] In a second aspect, the application further discloses a single crystal furnace comprising the above-mentioned heat preservation field.

[0010] In the application, an avoidance space is provided on the cylinder body of the insulation cylinder, and at least part of the second heater is located in the avoidance space, which can avoid opening holes in the furnace bottom insulation plate or the furnace bottom plate of the single crystal furnace. In this way, during the crystal pulling process, the heat in the hot field environment can be prevented from being lost from the openings on the furnace bottom insulation plate or the furnace bottom plate, thereby reducing heat loss and reducing crystal pulling power consumption.

[0011] In the application, a groove is provided on the inner wall of the insulation tube opposite to the crucible, and the notch of the groove faces the crucible, so that the insulation tube can block the longitudinal heat radiation of the first heater, prevent the first heater from transferring heat to the bottom, reduce heat loss, and reduce the power consumption of crystal pulling. At the same time, it prevents heat from baking the bottom of the quartz crucible, reduces the oxygen entering the silicon melt, and thus improves the quality of crystal pulling.

[0012] In the application, a protective tube is provided outside the first heater to protect the first heater and prevent the gas in the insulation tube from corroding the first heater.

[0013] In the application, the second heating electrode of the second heater is arranged at the bottom of the heat preservation tube, which can reduce the heat loss through the second electrode hole.

[0014] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0016] FIG1 is a schematic structural diagram of a heat preservation thermal field in an embodiment of the application;

[0017] FIG2 is a schematic structural diagram of a chassis in an embodiment of the application;

[0018] FIG3 is a schematic structural diagram of another thermal insulation field in an embodiment of the application.

[0019] Description of reference numerals:

[0020] 1-insulation tube, 11-upper insulation tube, 12-middle insulation tube, 121-first accommodating groove, 13-lower insulation tube, 131-first through hole, 132-second through hole, 133-second accommodating groove, 134-exhaust hole, 14-groove, 2-protective tube, 3-first heater, 31-first heating body, 32-first foot plate, 33-first heating electrode, 4-crucible, 5-crucible side, 6-chassis, 61-connecting part, 62-sealing part, 63-first electrode hole, 64-second electrode hole, 65-first avoidance hole, 7-second heater, 71-second heating body, 711-second avoidance hole, 72-second foot plate, 73-second heating electrode. Specific embodiments

[0021] In order to make the above-mentioned purposes, features and advantages of the application more obvious and easy to understand, the application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0022] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly refer to one or more of the features. In the description of the application, unless otherwise specified, "plurality" means two or more. Furthermore, "and / or" in the specification and claims refers to at least one of the connected items, and the character " / " generally indicates an "or" relationship between the connected items.

[0023] In the description of the application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the application.

[0024] In the description of the application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they can refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the application based on the specific circumstances.

[0025] First, one of the core concepts of the application embodiments is to disclose a heat preservation field for use in a single crystal furnace. The heat preservation field may specifically include: a heat preservation barrel 1 and a second heater 7. The second heater 7 is disposed within the heat preservation barrel 1, opposite the crucible 4, and can be used to heat the silicon material within the crucible 4. The second heater 7 is a bottom heater, disposed at the bottom of the crucible, and is used to heat and melt the silicon material within the crucible.

[0026] Optionally, an escape space is provided on the body of the heat-insulating cylinder 1 , and at least a portion of the second heater 7 is located in the escape space.

[0027] Optionally, the second heater 7 includes a second heating element 71; at least a portion of the second heating element 71 is located within the escape space. In this embodiment, the escape space can be provided on the body of the insulation cylinder 1 to accommodate the second heater 7, thereby avoiding opening a hole at the bottom of the single crystal furnace and preventing heat loss from the bottom of the single crystal furnace. In this embodiment, the portion of the second heating element 71 located within the escape space can be the second heating element lug connected to the second heating electrode 73, or it can be a portion of the second heating element 71 itself.

[0028] Optionally, the second heater 7 includes a second heating electrode 73 connected to the second heating body 71 , and at least a portion of the second heating electrode 73 is located in the avoidance space.

[0029] In the application embodiment, an escape space is provided on the cylinder body of the insulation cylinder 1, and at least a portion of the second heating body 71 of the second heater 7 is located in the escape space. The second heating electrode 73 of the second heater 7 passes through the escape space and extends out of the bottom of the cylinder body, which can avoid opening holes on the furnace bottom plate, i.e., the chassis 6, of the single crystal furnace. In this way, during the crystal pulling process, heat in the thermal field environment can be prevented from being lost from the openings on the furnace bottom insulation plate or the furnace bottom plate, thereby reducing heat loss and reducing crystal pulling power consumption.

[0030] Specifically, in the second heater 7, the second heating body 71 and the second heating electrode 73 can be directly or indirectly connected, and the second heating electrode 73 can drive the second heating body 71 to radiate heat when it is energized. Specifically, the avoidance space can be a through hole and / or an avoidance groove.

[0031] Optionally, the second heater 7 further includes a second footplate 72; one end of the second footplate 72 is connected to the second heating element 71, and the other end is connected to the second heating electrode 73, so that the second heating element 71 can be connected to the second heating electrode 73 via the second footplate 72, thereby achieving an indirect connection between the second footplate 72 and the second heating electrode 73. In this embodiment, the second footplate 72 can serve to support and connect the second heating element 71 and to provide power, or it can simply provide power; the specific components may include support legs, bolts, and other components.

[0032] Optionally, at least a portion of the second foot plate 72 and / or the second heating electrode 73 is located in the avoidance space.

[0033] In this embodiment, the body of the thermal insulation cylinder 1 may be provided with a second receiving groove 133 and a second through hole 132. The notch of the second receiving groove 133 faces the second heating element 71. The second through hole 132 extends axially along the thermal insulation cylinder 1 and communicates with the second receiving groove 133. The second through hole 132 and the second receiving groove 133 may be combined to form an escape space. At least a portion of the second heating element 71 is embedded in the second receiving groove 133, and the second foot plate 72 and / or the second heating electrode 73 are disposed in the second through hole 132. In this embodiment, the escape space includes the second through hole 132 and the second receiving groove 133. Of course, the escape space may also include other portions in addition to the second through hole 132 and the second receiving groove 133.

[0034] In the embodiment of the application, by opening the second receiving groove 133 and the second through hole 132 on the cylinder, an escape space is formed to avoid opening holes on the furnace bottom plate, thereby reducing heat loss in the thermal field.

[0035] Optionally, the second heater 7 can be arranged below the crucible 4, opposite to the bottom of the crucible 4, so that the second heater 7 heats the silicon material in the crucible 4 from the bottom of the crucible 4, which can improve the efficiency and uniformity of melting the silicon material.

[0036] Since the second heater 7 is disposed below the crucible 4 , the radial space occupied by the second heater 7 in the heat preservation tube 1 can be reduced, thereby rationally utilizing the space in the heat preservation tube 1 .

[0037] Specifically, the second heater 7 can be a flat plate heater. Using the second heater 7 to heat the bottom of the crucible 4 can improve the heating uniformity of the bottom of the crucible 4. In this embodiment, the flat plate heater can be a hollow structure with a groove body, or it can be a non-hollow structure. The specific structure is not limited in this embodiment.

[0038] In the embodiment of the application, at least a portion of the second heating body 71 is embedded in the second receiving groove 133, and the second foot plate 72 and / or the second heating electrode 73 are disposed in the second through hole 132, so that the second foot plate 72 and / or the second heating electrode 73 can be located within the barrel of the thermal insulation barrel 1, which can reduce the heat transferred by the second foot plate 72 and / or the second heating electrode 73 and avoid heat loss of the second heater 7. Alternatively, at least a portion of the second foot plate 72 or the second heating electrode 73 is disposed in the second receiving groove 133, the second heating body 71 is not in the second receiving groove, and the second heating electrode is located in the second through hole 132. In this embodiment, the second heating electrode 73 can be an electrode column.

[0039] Specifically, the circumference of the second heating body 71 may be partially embedded in the second accommodating groove 133 , and a second avoidance hole 711 may be provided in the middle of the second heating body 71 for avoiding the tow rod.

[0040] Optionally, as shown in Figure 1, the thermal insulation field further includes a first heater 3, specifically a side heater. An insulation barrel 1 is disposed around a crucible 4; a groove 14 is provided on the inner wall of the insulation barrel 1 opposite the crucible 4, with the opening of the groove 14 facing the crucible 4. The first heater 3 is at least partially disposed within the groove 14, allowing the insulation barrel to block longitudinal heat radiation from the first heater, preventing heat transfer from the first heater to the bottom, reducing heat loss and lowering crystal pulling power consumption. Furthermore, this prevents heat from baking the bottom of the quartz crucible, reducing oxygen ingress into the silicon melt, and thereby improving crystal pulling quality.

[0041] The heat preservation field in the embodiment of the application can be placed in a single crystal furnace to provide a thermal environment for the crystal pulling process to ensure the good growth of silicon rods. The heat preservation field can include a heat preservation tube 1, a protective tube 2, a first heater 3, and a crucible 4. The crucible 4 is used to hold silicon material. The first heater 3 is used to heat the silicon material in the crucible 4 to pull the crystal rod. The first heater 3 and the crucible 4 are both placed in the heat preservation tube 1. The heat preservation tube 1 can provide insulation, thereby reducing heat loss, improving the heating efficiency of the first heater 3, and thus increasing the crystal pulling rate.

[0042] Optionally, the heat preservation field includes a protective tube 2, which is arranged on a side of the first heater 3 away from the heat preservation tube. Specifically, the protective tube 2 is arranged between the first heater 3 and the crucible 4, and can seal at least part of the first heater in the groove 14.

[0043] Specifically, in the application embodiment, a groove 14 is provided on the inner wall of the insulation tube 1 opposite to the crucible 4, and the notch of the groove 14 faces the crucible 4. Since the protective tube 2 is arranged between the first heater 3 and the crucible 4, and can seal the first heater 3 in the groove 14, the protective tube 2 can block the airflow from eroding and corroding the first heater 3, thereby improving the service life of the first heater 3.

[0044] Specifically, since the first heater 3 is disposed within the groove 14, the sidewalls of the groove 14 can also block the longitudinal heat radiation of the first heater 3, thereby preventing heat from being radiated to the bottom of the crucible 4 and thereby reducing heat loss. The transverse direction is the radial direction of the heat-insulating tube 1, and the longitudinal direction is the axial direction of the heat-insulating tube 1.

[0045] Specifically, a groove 14 is provided on the inner wall of the heat-insulating cylinder 1. The notch of the groove 14 faces the crucible 4, facilitating the first heater 3 to radiate heat laterally to the crucible 4. The groove 14 blocks the longitudinal heat radiation from the first heater, preventing the first heater from heating the quartz crucible and the bottom of the crucible, thereby reducing the oxygen in the quartz crucible from entering the melt and lowering the oxygen content.

[0046] Specifically, at least a portion of the protective tube 2 can be embedded in the notch of the groove 14, and the end of the protective tube 2 can abut against the side wall of the groove 14. Alternatively, the protective tube 2 can be connected to the inner wall of the thermal insulation tube 1 via a connector. The specific configuration can be based on actual needs and is not specifically limited in the application embodiments.

[0047] Furthermore, the protective tube 2 can seal the first heater 3 in the groove 14, so that the protective tube 2 can seal the first heater 3 in the groove 14. In this way, during the process of pulling the crystal rod, the gas flows and carries away the volatiles, which can prevent the airflow from eroding the first heater.

[0048] Specifically, the protective tube 2 can be a carbon-carbon tube or a graphite tube, etc. The protective tube 2 can also transmit thermal radiation, thereby transferring the thermal radiation of the first heater 3 to the crucible 4, melting the silicon material in the crucible 4 for crystal pulling. Furthermore, in order to better transmit the thermal radiation of the first heater 3, the wall thickness of the thermal insulation tube 1 can be made thinner.

[0049] Specifically, the heat preservation field further includes a crucible side 5 and a drag rod. The crucible side 5 can be wrapped around the outer wall of the crucible 4 to protect the crucible 4; the drag rod can be set at the bottom of the crucible side 5 to support the crucible side 5 and the crucible 4.

[0050] In an optional embodiment of the application, the first heater 3 includes a first heating element 31 and a first heating electrode 33. The first heating element 31 is disposed around the crucible for heating the crucible; at least a portion of the first heating element 31 is disposed within the groove. The first heating element and the first heating electrode 33 may be directly or indirectly connected.

[0051] Optionally, the first heater 3 further includes a first foot plate 32 , one end of which is connected to the first heating body, and the other end of which is connected to the first heating electrode.

[0052] In this embodiment, the insulating cylinder 1 is provided with a first through-hole extending along its axis. Any one or more of the following: at least a portion of the first heating element, at least a portion of the first heating electrode, and at least a portion of the first footplate are located within the first through-hole. The first through-hole improves the thermal insulation performance of the insulating cylinder 1 during the crystal pulling process. Furthermore, at least a portion of the first heating electrode can be positioned within the first through-hole, preventing heat generated by the first heating electrode 33 from radiating to the crucible bottom during the crystal pulling process, thereby reducing crucible corrosion and oxygen content. Furthermore, the first heating electrode is positioned directly within the first through-hole, facilitating assembly and disassembly of the first heater 3.

[0053] In this embodiment, the first heating element 31 can be an integral or split structure; the first heating element is annular. A groove can be provided in the axial direction of the first heating element 31 to form a serpentine structure. In this embodiment, the first footplate 32 can be a support member, such as a support leg, that supports and electrically connects the first heating element; or it can simply be a connecting member, such as a bolt, that electrically connects the first heating element to the first heating electrode.

[0054] In the application embodiment, the first foot plate 32 and / or the first heating electrode 33 are arranged in the first through hole 131. Since the first through hole 131 is arranged on the cylinder body of the insulation cylinder 1, the first foot plate 32 and / or the first heating electrode 33 can be reduced to transfer the heat radiation of the first heating electrode 33 to the bottom of the crucible 4, which can increase the longitudinal temperature gradient of the silicon liquid and reduce the oxygen content transported to the crystal rod to obtain a low-oxygen single crystal.

[0055] Specifically, the cross-sectional shape of the first through hole 131 along the radial direction of the heat-insulating cylinder 1 may include at least one of a polygon, a circle, and an ellipse.

[0056] Specifically, the first heating electrode 33 may be a graphite electrode.

[0057] Specifically, in this embodiment, the wall thickness of the first heating body 31 along the radial direction of the heat-insulating tube 1 can be greater than or equal to the depth of the groove 14 along the radial direction of the heat-insulating tube 1; the first heating body 31 can be partially located within the groove 14, so that the heat-insulating tube 1 appropriately blocks the heat of the heater. In addition, the wall thickness of the first heating body 31 along the radial direction of the heat-insulating tube 1 can also be less than the depth of the groove 14 along the radial direction of the heat-insulating tube 1, and the first heater 3 can be completely embedded in the groove 14, so that the heat-insulating tube 1 can block more heat radiation to further reduce heat loss. The positional relationship or thickness relationship between the first heating body and the groove is selected according to the needs of the thermal field environment.

[0058] Optionally, the first heating electrode 33 can be an electrode column, which can pass through the first through hole 131, so that one end of the first heating electrode 33 extends out of the first through hole 131 and is electrically connected to the first foot plate 32, and the other end extends out of the first through hole 131 and is electrically connected to the copper electrode at the bottom of the insulation tube 1.

[0059] Optionally, the first foot plate 32 can extend in the direction away from the outer wall of the first heating body 31, can pass through the first through hole 131, and the first heating electrode 33 can be located at the bottom of the insulation tube 1. In this way, the first heating electrode 33 can be electrically connected to the copper electrode at the bottom of the insulation tube 1 while ensuring that the first heating electrode 33 is electrically connected to the first foot plate 32.

[0060] Optionally, part of the first foot plate 32 and part of the first heating electrode 33 can be located in the first through hole 131 to facilitate electrical connection between the first foot plate 32 and the first heating electrode 33. Moreover, the thermal insulation tube 1 can isolate the heat transfer between the first foot plate 32 and the first heating electrode 33.

[0061] Specifically, the first heating electrode 33 can be an electrode column, which can pass through the first through hole 131, or the first foot plate 32 can pass through the first through hole 131, and the first heating electrode 33 can be located at the bottom of the insulation tube 1, or part of the first foot plate 32 and part of the first heating electrode 33 can be located in the first through hole 131, which can increase the structural diversity of the first heater 3.

[0062] Optionally, the first foot plate 32 extends in a direction away from the outer wall of the first heating body 31; a first accommodating groove 121 is also provided on the barrel body of the thermal insulation barrel 1, the notch of the first accommodating groove 121 is opposite to the first through hole 131, and the first accommodating groove 121 is connected to the groove 14; the first foot plate 32 is arranged in the first accommodating groove 121.

[0063] In the embodiment of the application, the notch of the first receiving tank 121 is opposite the first through hole 131 and is connected to the groove 14, facilitating the placement of the first heater 3 and ensuring that one end of the first foot plate 32 is connected to the first heating body 31 and the other end is connected to the first heating electrode 33. Furthermore, the placement of the first foot plate 32 within the first receiving tank 121 can reduce the amount of heat transferred from the first foot plate 32 to the crucible 4, thereby increasing the longitudinal temperature gradient of the molten silicon and reducing the oxygen content transported to the crystal ingot, thereby obtaining a low-oxygen single crystal.

[0064] Specifically, the first receiving groove 121 can be connected to the first through hole 131 and the groove 14 respectively, so that the first foot plate 32 can be hidden on the cylinder body of the insulation cylinder 1, and the cylinder body of the insulation cylinder 1 can isolate the heat radiated from the first foot plate 32 to the crucible 4.

[0065] Optionally, the thermal insulation field further includes a chassis 6; the chassis 6 is arranged at the bottom of the thermal insulation tube 1, and is enclosed with the thermal insulation tube 1 to form a accommodating cavity for accommodating the crucible 4; a first electrode hole 63 is provided on the chassis 6 at a position opposite to the first through hole 131, and the first electrode hole 63 is used to pass the first heating electrode 33.

[0066] In the embodiment of the application, the chassis 6 is disposed at the bottom of the insulation cylinder 1, conveniently forming a housing cavity for the crucible 4 with the insulation cylinder 1. Furthermore, the heat radiation from the first heater 3 is concentrated within the housing cavity, thereby improving the heating efficiency of the crucible 4. A first electrode hole 63 is provided in the chassis 6 to facilitate electrical connection between the first heating electrode 33 and the copper electrode at the bottom of the single crystal furnace through the first electrode hole 63.

[0067] Specifically, the first electrode hole 63 is opposite to the first through hole 131. Since the first through hole 131 is arranged in the barrel of the thermal insulation barrel 1, the first electrode hole 63 can be prevented from being directly connected to the accommodating cavity, and heat can be prevented from being dissipated from the first electrode hole 63, further reducing heat loss.

[0068] Specifically, as shown in Figure 2, the chassis 6 may include a connecting portion 61 and a sealing portion 62; the sealing portion 62 may be arranged around the connecting portion 61; the connecting portion 61 may be abutted and fixed to the barrel of the thermal insulation barrel 1, and the sealing portion 62 may be used to enclose and form a accommodating cavity; the first electrode hole 63 may be arranged in the connecting portion 61.

[0069] Specifically, the connecting portion 61 and the blocking portion 62 can be integrally formed or spliced ​​together, etc., and can be specifically configured according to actual needs, and the application embodiment does not make any specific limitations on this.

[0070] Specifically, the numbers of the first electrode holes 63 , the first through holes 131 and the first heating electrodes 33 are arranged in a one-to-one correspondence.

[0071] Specifically, the chassis 6 can be a solid felt disc to provide better heat insulation. The chassis 6 can also be provided with a first avoidance hole 65 for avoiding the tow bar.

[0072] Specifically, the shape of the first electrode hole 63 may include: at least one of a polygonal hole, a circular hole and an elliptical hole. The shape of the first electrode hole 63 can be set with reference to the shape of the first through hole 131, and can be set according to actual needs. The application embodiment does not make specific limitations on this.

[0073] Specifically, the first heater 3 can be a main heater, that is, a side heater, which can surround the upper end of the crucible 4; the second heater 7 can be a secondary heater, that is, a bottom heater, which can be arranged below the crucible 4.

[0074] Specifically, the second through hole 132 and the first through hole 131 may be arranged at intervals along the circumference of the heat preservation cylinder 1 .

[0075] Furthermore, the thermal insulation field also includes a chassis 6; the chassis 6 is arranged at the bottom of the thermal insulation tube 1, and is enclosed with the thermal insulation tube 1 to form a accommodating cavity for accommodating the crucible 4; a second electrode hole 64 is provided on the chassis 6 at a position opposite to the second through hole 132, and the second electrode hole 64 is used to pass the second heating electrode 73.

[0076] In the application embodiment, the second through hole 132 is arranged on the cylinder body of the thermal insulation cylinder 1, and the second electrode hole 64 is connected to the second through hole 132, which can avoid direct connection between the second electrode hole 64 and the accommodating cavity, reduce heat dissipation from the second electrode hole 64, and thus reduce heat loss in the accommodating cavity.

[0077] Specifically, the second heating electrode 73, the second electrode hole 64 and the second through hole 132 are arranged in a one-to-one correspondence. The shapes of the second electrode hole 64 and the second through hole 132 can be set with reference to the shape of the second heating electrode 73, and the application embodiment does not make specific limitations on this.

[0078] Optionally, an exhaust hole 134 is provided on the cylinder body of the heat-insulating cylinder 1 opposite to the crucible 4 , and the exhaust hole 134 can penetrate the cylinder body of the heat-insulating cylinder 1 along the radial direction of the heat-insulating cylinder 1 .

[0079] In the embodiment of the application, an exhaust hole 134 is provided on the body of the heat-insulating cylinder 1 opposite the crucible 4. Since the second heater 7 is disposed below the crucible 4, the exhaust hole 134 is located above the second heater 7. This allows airflow to exit the exhaust hole 134 from the side, preventing airflow from eroding and corroding the second heater 7. Furthermore, the exhaust hole 134 can be positioned at the bottom to avoid heat loss from radiation at the bottom.

[0080] Optionally, an exhaust pipe may be embedded in the exhaust hole 134 to exhaust gas through the exhaust pipe to prevent the airflow from directly scouring the insulation tube 1, so as to achieve the purpose of protecting the insulation tube 1. Specifically, the exhaust pipe may be made of silicon carbide or coated with a silicon carbide coating.

[0081] In an optional embodiment of the application, as shown in Figure 3, the insulation tube 1 may include an upper insulation tube 11, a middle insulation tube 12 and a lower insulation tube 13 arranged in sequence along its axial direction; the inner diameter of the middle insulation tube 12 is larger than the inner diameter of the upper insulation tube 11 and the inner diameter of the lower insulation tube 13, and the middle insulation tube 12, the upper insulation tube 11 and the lower insulation tube 13 are combined to form a groove 14; the protective tube 2 can be arranged in the groove and respectively abut against the inner wall of the upper insulation tube 11 and the inner wall of the lower insulation tube 13.

[0082] In the embodiment of the application, the inner diameter of the middle insulation tube 12 is larger than the inner diameters of the upper insulation tube 11 and the lower insulation tube 13, respectively. This allows the inner wall of the middle insulation tube 12 to be retracted into the inner walls of the upper insulation tube 11 and the lower insulation tube 13, respectively, to facilitate forming a groove 14 on the inner wall of the insulation tube 1 for placing the first heater 3. Furthermore, the protective tube 2 is disposed within the groove and abuts against the inner walls of the upper insulation tube 11 and the lower insulation tube 13, respectively, to facilitate sealing the first heater 3 within the groove 14. Alternatively, a groove may be provided on the inner wall of the upper insulation tube or the middle insulation tube.

[0083] Specifically, the inner diameter of the lower heat-insulating tube 13 is smaller than the inner diameter of the middle heat-insulating tube 12 , so that the end of the lower heat-insulating tube 13 can block the longitudinal heat radiation of the first heater 3 .

[0084] Specifically, in the embodiment of the application, the first through hole 131 may pass through the lower heat-insulating tube 13 to facilitate the placement of the first heater 3 . The second through hole 132 may pass through the lower heat-insulating tube 13 to facilitate the placement of the second heater 7 .

[0085] Optionally, the upper insulation tube 11, the middle insulation tube 12 and the lower insulation tube 13 can be independently provided, and then can be spliced ​​together to form a spliced ​​split structure. Alternatively, the upper insulation tube 11, the middle insulation tube 12 and the lower insulation tube 13 are combined into an integrally formed structure to further improve the structural stability of the insulation tube 1. In addition, the upper insulation tube 11, the middle insulation tube 12 and the lower insulation tube 13 can be integrally formed structures, or the upper insulation tube 11, the middle insulation tube 12 and the lower insulation tube 13 can each be composed of multiple cylinders. The specific configuration can be based on actual needs, and the application embodiment does not make specific limitations on this.

[0086] Specifically, along the axial direction of the insulation tube 1 , the upper insulation tube 11 can be located above the crucible 4 , the middle insulation tube 12 can surround the upper part of the crucible 4 , and the lower insulation tube 13 can surround the lower part of the crucible 4 .

[0087] Specifically, the wall thickness of the lower insulation tube 13 can be greater than the wall thickness of the middle insulation tube 12, and the inner diameter of the middle insulation tube 12 is greater than the inner diameter of the lower insulation tube 13, so that the inner wall of the middle insulation tube 12 is retracted into the inner wall of the lower insulation tube 13 to form a space for placing the first heater 3.

[0088] In another optional embodiment of the application, the insulation tube 1 may include a middle insulation tube 12 and a lower insulation tube 13 arranged in sequence along its axial direction; the inner diameter of the middle insulation tube 12 is larger than the inner diameter of the lower insulation tube 13, and the middle insulation tube 12 and the lower insulation tube 13 are enclosed to form a step; one of the specific structures of the above-mentioned groove 14 can be considered as the step structure; the protective tube 2 can be arranged on the step.

[0089] In the embodiment of the application, the inner diameter of the middle insulation tube 12 is larger than that of the lower insulation tube 13, allowing the inner wall of the middle insulation tube 12 to be retracted from the inner wall of the lower insulation tube 13, forming a step. This in turn forms a groove 14 on the inner wall of the insulation tube 1 for accommodating the first heater 3. Furthermore, the protective tube 2 is positioned on the step and separates the first heater 3 from the crucible 4, thereby preventing airflow from eroding and corroding the first heater 3.

[0090] Specifically, in the embodiment of the application, the first through hole 131 may pass through the lower heat-insulating tube 13 to facilitate the placement of the first heater 3 . The second through hole 132 may pass through the lower heat-insulating tube 13 to facilitate the placement of the second heater 7 .

[0091] Optionally, the middle insulation tube 12 and the lower insulation tube 13 can be independently provided and then can be spliced ​​to form a spliced ​​split structure. Alternatively, the middle insulation tube 12 and the lower insulation tube 13 can also be an integrally formed structure to further improve the structural stability of the insulation tube 1. In addition, the middle insulation tube 12 and the lower insulation tube 13 can each be an integrally formed structure, or the middle insulation tube 12 and the lower insulation tube 13 can each be composed of multiple cylinders. The specific configuration can be based on actual needs, and the application embodiment does not make specific limitations on this.

[0092] Optionally, the heat-insulating cylinder 1 can be an integrally formed cylindrical structure made of solid felt, so that the heat-insulating cylinder 1 can be a one-layer or two-layer structure with a simple structure and low cost.

[0093] The heat preservation thermal field described in the application embodiment has at least the following advantages:

[0094] In the application embodiment, an avoidance space is provided on the cylinder body of the insulation cylinder, and at least a part of the second heating body of the second heater is located in the avoidance space, which can avoid opening holes on the furnace bottom plate of the single crystal furnace. In this way, during the crystal pulling process, the heat in the thermal field environment can be avoided from being lost through the openings on the furnace bottom plate, thereby reducing heat loss and reducing the power consumption of crystal pulling.

[0095] On the second aspect, the application embodiment further discloses a single crystal furnace, comprising a second heater 7, which is a bottom heater located at the bottom of the crucible for heating the crucible.

[0096] In addition, the single crystal furnace can specifically include an insulation tube 1, a first heater 3, a second heater 7 and a crucible 4 for accommodating silicon material; wherein, the insulation tube 1 is arranged around the crucible 4; the first heater and the second heater are arranged in the insulation tube, and at least part of the second heater is located in the avoidance space.

[0097] Optionally, the second heater includes a second heating body; an escape space is provided on the cylinder body of the heat preservation cylinder, and at least a part of the second heating body is located in the escape space.

[0098] Optionally, a groove 14 is provided on the inner wall of the heat-insulating cylinder 1 opposite the crucible 4, with the opening of the groove 14 facing the crucible 4; at least a portion of the first heater can be disposed within the groove. The groove can take various forms, such as a trough structure with the opening facing one side or a stepped structure with the opening facing both sides, which are not specifically limited in this embodiment. The groove primarily serves to prevent some heat from being transferred downward from the heater.

[0099] In the application embodiment, a groove 14 is provided on the inner wall of the insulation tube 1 opposite to the crucible 4, the notch of the groove 14 faces the crucible 4, and the first heater 3 is arranged in the groove 14, so that the insulation tube 1 can block the longitudinal heat radiation of the first heater 3, avoid the first heater 3 from transferring heat to the bottom, reduce the heat radiation to the bottom of the quartz crucible, and thus improve the quality of crystal pulling.

[0100] Specifically, the second heater 7 is disposed below the crucible 4 and opposite the bottom of the crucible 4, so that the second heater 7 can heat the bottom of the crucible 4, further increasing the melting rate of the silicon material in the crucible 4. Since the second heater 7 is disposed below the crucible 4, the radial space occupied by the second heater 7 in the insulation cylinder 1 can be reduced, thereby rationally utilizing the space in the insulation cylinder 1.

[0101] Optionally, the second heater 7 includes a second heating body 71, a second heating electrode 73 and a second foot plate 72; one end of the second foot plate 72 is connected to the second heating body 71, and the other end is connected to the second heating electrode 73; a second accommodating groove 133 and a second through hole 132 are provided on the barrel of the thermal insulation tube 1, the notch of the second accommodating groove 133 faces the second heating body 71, the second through hole 132 is connected to the second accommodating groove 133 along the axial direction of the thermal insulation tube 1, and the second through hole 132 extends along the axial direction of the thermal insulation tube 1 and is connected to the second accommodating groove 133; at least part of the second heating body 71 is embedded in the second accommodating groove 133, and the second foot plate 72 and / or the second heating electrode 73 are arranged in the second through hole 132.

[0102] In the application embodiment, at least a portion of the second heating body 71 is embedded in the second accommodating groove 133, and the second foot plate 72 and / or the second heating electrode 73 are arranged in the second through hole 132, so that the second foot plate 72 and / or the second heating electrode 73 can be located in the barrel of the thermal insulation barrel 1, which can reduce the heat transfer of the second foot plate 72 and / or the second heating electrode 73 and avoid heat loss of the second heater 7.

[0103] Specifically, the circumference of the second heating body 71 may be partially embedded in the second accommodating groove 133 , and a second avoidance hole 711 may be provided in the middle of the second heating body 71 for avoiding the tow rod.

[0104] Specifically, the second heating electrode 73 may also be an electrode column. The second heating electrode 73 may be configured with reference to the first heating electrode 33 , and will not be described in detail in the application embodiment.

[0105] Specifically, the second through hole 132 and the first through hole 131 may be arranged at intervals along the circumference of the heat preservation cylinder 1 .

[0106] In an optional embodiment of the application, the insulation tube 1 may include an upper insulation tube 11, a middle insulation tube 12 and a lower insulation tube 13 arranged in sequence along its axial direction; the inner diameter of the middle insulation tube 12 is larger than the inner diameter of the upper insulation tube 11 and the inner diameter of the lower insulation tube 13, and the middle insulation tube 12, the upper insulation tube 11 and the lower insulation tube 13 are enclosed to form a groove 14; the second heater is arranged in the lower insulation tube 13.

[0107] In the application embodiment, the inner diameter of the middle insulation tube 12 is larger than the inner diameter of the upper insulation tube 11 and the inner diameter of the lower insulation tube 13, so that the inner wall of the middle insulation tube 12 can be retracted into the inner wall of the upper insulation tube 11 and the inner wall of the lower insulation tube 13, respectively, to facilitate the formation of a groove 14 on the inner wall of the insulation tube 1 for placing the first heater 3.

[0108] Specifically, the inner diameter of the lower heat-insulating tube 13 is smaller than the inner diameter of the middle heat-insulating tube 12 , so that the end of the lower heat-insulating tube 13 can block the longitudinal heat radiation of the first heater 3 .

[0109] In another optional embodiment of the application, the insulation tube 1 may include a middle insulation tube 12 and a lower insulation tube 13 arranged in sequence along its axial direction; the inner diameter of the middle insulation tube 12 is larger than the inner diameter of the lower insulation tube 13, and the middle insulation tube 12 and the lower insulation tube 13 are enclosed to form a step; the second heater is arranged in the lower insulation tube 13.

[0110] In the application embodiment, the inner diameter of the middle insulation tube 12 is larger than the inner diameter of the lower insulation tube 13, so that the inner wall of the middle insulation tube 12 can be retracted into the inner wall of the lower insulation tube 13 to form a step, thereby forming a groove 14 on the inner wall of the insulation tube 1 for placing the first heater 3.

[0111] The single crystal furnace described in the application embodiment has at least the following advantages:

[0112] In the application embodiment, an avoidance space is provided on the cylinder body of the insulation cylinder, and at least a part of the second heating body of the second heater is located in the avoidance space, which can avoid opening holes on the furnace bottom plate of the single crystal furnace. In this way, during the crystal pulling process, the heat in the thermal field environment can be avoided from being lost through the openings on the furnace bottom plate, thereby reducing heat loss and reducing the power consumption of crystal pulling.

[0113] Although the preferred embodiments of the application embodiments have been described, those skilled in the art may make additional changes and modifications to these embodiments once they become aware of the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the application embodiments.

[0114] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or terminal device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or terminal device that includes the element.

[0115] The above is a detailed introduction to the thermal insulation field and single crystal furnace provided by the application. Specific examples are used in this article to illustrate the principles and implementation methods of the application. The description of the above embodiments is only used to help understand the method of the application and its core ideas. At the same time, for general technical personnel in this field, according to the ideas of the application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the application.

Claims

1. A heat preservation thermal field, characterized in that: The heat preservation field includes a heat preservation tube and a second heater; wherein, The second heater is arranged in the heat-insulating cylinder; a retreat space for at least partially avoiding the second heater is arranged on the cylinder body of the heat-insulating cylinder; the second heater is a bottom heater.

2. The heat preservation thermal field according to claim 1, characterized in that: The second heater includes a second heating body and a second heating electrode connected to the second heating body. At least a portion of the second heating electrode and / or at least a portion of the second heating body are located in the avoidance space.

3. The heat preservation thermal field according to claim 2, characterized in that: The second heater also includes a second foot plate; One end of the second foot plate is connected to the second heating body, and the other end is connected to the second heating electrode; at least a part of the second foot plate is located in the avoidance space.

4. The heat preservation thermal field according to claim 3, characterized in that: The heat preservation cylinder is provided with a second receiving groove and a second through hole, the notch of the second receiving groove faces the second heating body, the second through hole extends along the axial direction of the heat preservation cylinder and communicates with the second receiving groove; the avoidance space includes the second through hole and the second receiving groove; At least a portion of the second heating body is embedded in the second receiving groove, and the second foot plate and / or the second heating electrode are arranged in the second through hole.

5. The heat preservation thermal field according to claim 1, characterized in that: The heat preservation thermal field comprises a first heater; the first heater is a side heater; A groove is provided on the inner wall of the heat preservation cylinder, and the notch of the groove faces the first heater; The first heater is at least partially disposed in the groove.

6. The heat preservation thermal field according to claim 5, characterized in that: The heat preservation field includes a protection tube, The protection tube is arranged on a side of the first heater away from the heat preservation tube, and seals at least a part of the first heater in the groove.

7. The heat preservation thermal field according to claim 5, characterized in that: The first heater comprises a first heating body and a first heating electrode connected to the first heating body; At least a portion of the first heat-generating body is disposed in the groove.

8. The heat preservation thermal field according to claim 7, characterized in that: The heat-insulating cylinder body is provided with a first through hole which is conductive along its axial direction; At least part of the first heat generating body and / or at least part of the first heating electrode is arranged in the first through hole.

9. The heat preservation thermal field according to claim 7, characterized in that: The first heater further includes a first foot plate; one end of the first foot plate is connected to the first heating body, and the other end is connected to the first heating electrode; The heat-insulating cylinder body is provided with a first through hole which is conductive along its axial direction; At least a portion of the first foot plate is disposed in the first through hole.

10. The heat preservation thermal field according to any one of claims 7 to 9, characterized in that: The first heating electrode is an electrode column.

11. The heat preservation thermal field according to claim 9, characterized in that: The first foot plate extends in a direction away from the outer wall of the first heat-generating body; The body of the heat preservation cylinder is further provided with a first receiving groove, the notch of the first receiving groove is opposite to the first through hole, and the first receiving groove is communicated with the groove; The first foot plate is at least partially disposed in the first accommodating groove.

12. The heat preservation thermal field according to claim 8 or 9, characterized in that: The heat preservation thermal field also includes a chassis; The bottom plate is arranged at the bottom of the heat preservation tube and is enclosed with the heat preservation tube to form a receiving cavity for receiving the crucible; A first electrode hole is provided on the chassis at a position opposite to the first through hole, and the first electrode hole is used for passing the first heating electrode.

13. The heat preservation thermal field according to claim 4, characterized in that: The heat preservation thermal field also includes a chassis; The bottom plate is arranged at the bottom of the heat preservation tube and is enclosed with the heat preservation tube to form a receiving cavity for receiving the crucible; A second electrode hole is provided on the chassis at a position opposite to the second through hole, and the second electrode hole is used for passing the second heating electrode.

14. The heat preservation thermal field according to claim 1, characterized in that: An exhaust hole is arranged on the cylinder body of the heat-insulating cylinder, and the exhaust hole penetrates the cylinder body of the heat-insulating cylinder along the radial direction of the heat-insulating cylinder.

15. The heat preservation thermal field according to claim 5, characterized in that: The heat-insulating tube comprises an upper heat-insulating tube, a middle heat-insulating tube and a lower heat-insulating tube which are arranged in sequence along the axial direction thereof; The inner diameter of the middle heat-insulating tube is larger than the inner diameter of the upper heat-insulating tube and the inner diameter of the lower heat-insulating tube, respectively. The middle heat-insulating tube, the upper heat-insulating tube and the lower heat-insulating tube enclose the groove.

16. The heat preservation thermal field according to claim 15, characterized in that: The heat preservation thermal field further includes a protection tube, which is arranged in the groove and abuts against the upper heat preservation tube and the lower heat preservation tube respectively.

17. The heat preservation thermal field according to claim 15, characterized in that: The upper heat-insulating cylinder, the middle heat-insulating cylinder and the lower heat-insulating cylinder are respectively integrally formed structures; Alternatively, any one or more of the upper heat-insulating tube, the middle heat-insulating tube and the lower heat-insulating tube are of a spliced ​​split structure.

18. The heat preservation thermal field according to claim 5, characterized in that: The heat-insulating tube comprises a middle heat-insulating tube and a lower heat-insulating tube which are arranged in sequence along the axial direction thereof; The inner diameter of the middle heat-insulating tube is greater than the inner diameter of the lower heat-insulating tube, and the middle heat-insulating tube and the lower heat-insulating tube are enclosed to form a step; and the first heater is at least partially arranged at the step.

19. The heat preservation thermal field according to claim 18, characterized in that: The heat preservation thermal field further includes a protection tube, and the protection tube is arranged at the step.

20. The heat preservation thermal field according to claim 18, characterized in that: The middle insulation cylinder and the lower insulation cylinder are respectively integrally formed structures; Alternatively, the middle insulation cylinder and / or the lower insulation cylinder are / is a spliced ​​split structure.

21. A single crystal furnace, characterized in that: The thermal insulation field comprises the thermal insulation field as described in any one of claims 1 to 20.

22. The single crystal furnace according to claim 21, characterized in that: The single crystal furnace also includes a first heater. A groove is arranged on the inner wall of the heat preservation tube, and the notch of the groove faces the first heater. The first heater is at least partially arranged in the groove.

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