Thermal insulation structure and monocrystalline silicon straight pulling furnace

Abstract

The utility model relates to the technical field of heating furnaces, in particular to a heat preservation structure and a monocrystalline silicon czochralski furnace, and aims to solve the problem of poor heat preservation performance of an existing heat preservation structure. Therefore, the heat preservation structure comprises a heat reflection layer on the outer layer, a vacuum heat insulation layer on the middle layer and a heat preservation felt layer on the inner layer, and the outer side face and the inner side face of the vacuum heat insulation layer are connected with the heat reflection layer and the heat preservation felt layer respectively. The heat reflecting layer on the outer layer of the heat preservation structure can effectively reflect high-temperature radiant heat in a furnace, reduce heat loss to the outside in a radiation mode and protect the heat preservation material on the inner layer from being directly eroded by high temperature, the vacuum heat insulation layer on the middle layer can eliminate heat conduction and convection of gas molecules, extremely low heat conductivity is achieved, and the service life of the heat preservation structure is prolonged. And the heat preservation felt layer located on the inner layer serves as a heat preservation layer making direct contact with the furnace body, heat conduction and permeation can be effectively blocked, and the heat preservation structure has the better heat preservation effect.

Description

Technical Field

[0001] This utility model relates to the field of heating furnace technology, specifically providing a heat preservation structure and a single crystal silicon Czochralski furnace. Background Technology

[0002] As a key piece of equipment for producing high-purity single-crystal silicon rods, the internal temperature of the Czochralski furnace must be precisely controlled within a high-temperature range to ensure the quality of crystal growth.

[0003] However, traditional insulation structures such as ceramic fiber and mineral wool have problems such as high thermal conductivity, limited temperature resistance, and easy aging and shedding after long-term use. These problems lead to serious heat loss from the furnace body, increased energy consumption, and affect the uniformity of temperature distribution inside the furnace, thus affecting the quality of the crystals.

[0004] Therefore, a new technical solution is needed in this field to solve the above problems. Utility Model Content

[0005] The present invention aims to solve the above-mentioned technical problems, namely, to solve the problem of poor thermal insulation performance of existing thermal insulation structures.

[0006] In a first aspect, the present invention provides a thermal insulation structure, the thermal insulation structure comprising an outer heat-reflective layer, a middle vacuum insulation layer, and an inner thermal insulation felt layer, wherein the outer and inner sides of the vacuum insulation layer are respectively connected to the heat-reflective layer and the thermal insulation felt layer.

[0007] In the preferred embodiment of the above-mentioned thermal insulation structure, the heat reflective layer includes a ceramic substrate, the inner side of the ceramic substrate is connected to the vacuum insulation layer, and the outer side of the ceramic substrate is provided with a metal film.

[0008] In the preferred embodiment of the above-mentioned thermal insulation structure, the ceramic matrix is ​​an alumina ceramic matrix; and / or

[0009] The metal film is a silver film or a gold film.

[0010] In the preferred embodiment of the above-mentioned thermal insulation structure, the vacuum insulation layer is a vacuum insulation board.

[0011] In the preferred embodiment of the above-mentioned thermal insulation structure, the vacuum insulation panel has a sealed cavity inside, which is filled with a gas adsorbent.

[0012] In the preferred embodiment of the above-mentioned thermal insulation structure, the thermal insulation felt layer is a nano-aerogel felt layer.

[0013] In the preferred embodiment of the above-mentioned thermal insulation structure, the thickness of the heat reflective layer is 15mm to 25mm; and / or

[0014] The thickness of the vacuum insulation layer is 60mm to 100mm; and / or

[0015] The thickness of the thermal insulation felt layer is 30mm to 50mm.

[0016] In the preferred embodiment of the above-mentioned insulation structure, the insulation structure is configured as a cylindrical structure, which is formed by multiple insulation modules, and the multiple insulation modules are distributed along the circumference of the cylindrical structure.

[0017] In the preferred embodiment of the above-mentioned insulation structure, a protrusion is provided on the first side end face of the insulation module, and a groove is provided on the second side end face of the insulation module. A first connecting hole is provided on the protrusion, and a second connecting hole is provided on the insulation module at a position corresponding to the groove. The protrusion on one insulation module is inserted into the groove of another insulation module, and the first connecting hole and the second connecting hole are aligned. The insulation module also includes a pin, which is inserted into the first connecting hole and the second connecting hole to fix the two insulation modules together.

[0018] In a second aspect, the present invention also provides a single-crystal silicon Czochralski furnace, including the above-mentioned heat preservation structure.

[0019] By adopting the above technical solution, the insulation structure of this utility model is configured as a multi-layer composite structure, including at least a heat-reflective layer, a vacuum insulation layer, and an insulation felt layer. The insulation felt layer is located on the inner side, the heat-reflective layer on the outer side, and the vacuum insulation layer between the insulation felt layer and the heat-reflective layer. This configuration significantly improves the insulation effect of the insulation structure. Specifically, the outer heat-reflective layer effectively reflects high-temperature radiant heat from the furnace, reducing heat loss to the outside through radiation, while protecting the inner insulation material from direct high-temperature erosion. The middle vacuum insulation layer eliminates heat conduction and convection of gas molecules, achieving extremely low thermal conductivity, thereby significantly reducing heat conduction loss. The inner insulation felt layer, as the insulation layer in direct contact with the furnace body, effectively blocks heat conduction and penetration.

[0020] Furthermore, the thermal insulation structure of this invention, by using a ceramic substrate and setting a metal film layer on the outer surface of the ceramic substrate, gives the thermal insulation structure of this invention better high temperature resistance, corrosion resistance and higher reflectivity.

[0021] Furthermore, the thermal insulation structure of this invention, by setting the thermal insulation felt layer as a nano-aerogel felt layer, gives the thermal insulation structure a lower thermal conductivity and superior thermal insulation performance.

[0022] Furthermore, the insulation structure of this utility model, by setting the insulation structure as a cylindrical structure, can fit more tightly with the inner wall of the furnace body, thereby further improving the insulation effect. In addition, by setting the insulation structure as a cylindrical structure composed of multiple insulation modules, it is beneficial to reduce the assembly difficulty of the insulation structure, thereby facilitating the quick installation of the insulation structure onto the inner wall of the furnace body.

[0023] Furthermore, the insulation structure of this utility model provides protrusions and grooves on the two side end faces of the insulation module, which facilitates the quick insertion of two insulation modules together, and then the two insulation modules are fixedly connected by inserting pins into them.

[0024] Furthermore, the monocrystalline silicon Czochralski furnace provided by this utility model, based on the above-mentioned technical solution, includes the above-mentioned insulation structure, and thus possesses the technical effects of the above-mentioned insulation structure. Compared with the monocrystalline silicon Czochralski furnace before the improvement, the monocrystalline silicon produced by the monocrystalline silicon Czochralski furnace of this utility model has more stable and reliable quality. Attached Figure Description

[0025] The preferred embodiments of this utility model are described below with reference to the accompanying drawings, in which:

[0026] Figure 1 This is a schematic diagram of the insulation structure and furnace body of this utility model;

[0027] Figure 2 This is a schematic diagram of the thermal insulation structure of this utility model;

[0028] Figure 3 This is a schematic diagram of the insulation module of the insulation structure of this utility model.

[0029] List of reference numerals in the attached diagram:

[0030] 1. Furnace body; 2. Heat reflective layer; 3. Vacuum insulation layer; 4. Insulation felt layer; 5. Pin; 6. Protrusion; 7. Groove; 8. First connecting hole; 9. Second connecting hole. Detailed Implementation

[0031] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0032] For example, although the embodiments described below are introduced in conjunction with a single-crystal silicon Czochralski furnace, the heat preservation structure of this utility model is still applicable to other types of heating furnaces. Such adjustments and changes to the application do not deviate from the principles and scope of this utility model and should be limited to the protection scope of this utility model.

[0033] It should be noted that in the description of this utility model, terms such as "upper," "lower," "top," and "bottom," which indicate direction or positional relationships, are based on the direction or positional relationships shown in the accompanying drawings. These are used merely for ease of description and do not indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0034] Furthermore, it should be noted that in the description of this utility model, unless otherwise explicitly specified and limited, the terms "set," "connect," and "install" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0035] Based on the problem of poor thermal insulation performance of existing thermal insulation structures pointed out in the background art, this utility model provides a thermal insulation structure and a single crystal silicon Czochralski furnace, aiming to improve the thermal insulation effect of the thermal insulation structure by adopting a multi-layer thermal insulation structure.

[0036] Specifically, this utility model provides a single-crystal silicon Czochralski furnace, such as Figure 1 As shown, the single-crystal silicon Czochralski furnace includes a furnace body 1 and an insulation structure installed inside the furnace body 1. The insulation structure is fixedly installed on the inner wall of the furnace body 1.

[0037] The thickness of the insulation structure is preferably 100mm to 180mm.

[0038] For example, those skilled in the art can set the thickness of the insulation structure to 100mm, 110mm, 120mm, 130mm, 140mm, 150mm, 160mm, 170mm, or 180mm in practical applications. Among these, the optimal thickness of the insulation structure is 140mm.

[0039] like Figure 1 As shown, the thermal insulation structure of this utility model includes an outer heat-reflective layer 2, a middle vacuum insulation layer 3, and an inner thermal insulation felt layer 4. The outer and inner sides of the vacuum insulation layer 3 are respectively connected to the heat-reflective layer 2 and the thermal insulation felt layer 4.

[0040] In other words, the insulation structure of this utility model is a multi-layer composite structure, including at least a heat-reflective layer 2, a vacuum insulation layer 3, and an insulation felt layer 4. The insulation felt layer 4 is located on the inner side and is attached to the inner wall of the furnace body 1. The heat-reflective layer 2 is located on the outer side. The vacuum insulation layer 3 is located between the insulation felt layer 4 and the heat-reflective layer 2. Through the above arrangement, the insulation effect of the insulation structure can be greatly improved.

[0041] Specifically, the outer heat-reflecting layer 2 can effectively reflect the high-temperature radiant heat inside the furnace, reducing heat loss to the outside through radiation, while protecting the inner insulation material from direct high-temperature corrosion. The middle vacuum insulation layer 3 can eliminate the heat conduction and convection of gas molecules, achieving extremely low thermal conductivity, thereby significantly reducing heat conduction loss. The inner insulation felt layer 4, as the insulation layer in direct contact with the furnace body 1, can effectively block heat conduction and penetration.

[0042] Preferably, such as Figure 1 As shown, the thermal insulation structure of this utility model is configured as a cylindrical structure.

[0043] Among them, the inner wall of the furnace body 1 of the single crystal silicon Czochralski furnace is cylindrical, and the heat preservation structure is set as a cylindrical structure, which can fit more tightly with the inner wall of the furnace body 1 and further improve the heat preservation effect.

[0044] Preferably, such as Figure 1 As shown, the cylindrical structure is formed by multiple insulation modules, which are distributed circumferentially along the cylindrical structure.

[0045] In other words, the insulation structure of this utility model is not a single cylindrical structure, but a cylindrical structure formed by multiple insulation modules. Each insulation module is arc-shaped and has the same structure, including the heat reflective layer 2, vacuum insulation layer 3, and insulation felt layer 4 described above. The insulation felt layer 4 is located on the inner side and is attached to the inner wall of the furnace body 1. The heat reflective layer 2 is located on the outer side, and the vacuum insulation layer 3 is located between the insulation felt layer 4 and the heat reflective layer 2.

[0046] By setting the insulation structure as a cylindrical structure composed of multiple insulation modules, the assembly difficulty of the insulation structure is reduced, which facilitates the rapid installation of the insulation structure onto the inner wall of the furnace body 1.

[0047] For example, such as Figure 1 As shown, there are four insulation modules, each with a 90-degree arc, and the four insulation modules form a 360-degree cylindrical structure.

[0048] It should be noted that the number of insulation modules is not limited to the four mentioned above. For example, the number of insulation modules can be set to two, with both insulation modules having an arc of 180 degrees; or the number of insulation modules can be set to three, with all three insulation modules having an arc of 120 degrees; or the number of insulation modules can be set to six, with all six insulation modules having an arc of 60 degrees, and so on. Such adjustments and changes to the specific number of insulation modules do not deviate from the principle and scope of this utility model and should all be limited to the protection scope of this utility model.

[0049] Furthermore, it should be noted that, in practical applications, those skilled in the art can directly attach each insulation module of the insulation structure to the inner wall of the furnace body 1, or they can use adhesive bonding to fix each insulation module to the inner wall of the furnace body 1, or they can fix the two together by setting a connection structure, etc. Such adjustments and changes to the specific connection method between the insulation structure and the furnace body 1 do not deviate from the principle and scope of this utility model, and should all be limited to the protection scope of this utility model.

[0050] Furthermore, it should be noted that, in practical applications, those skilled in the art can use adhesive bonding to fix two adjacent insulation modules, or they can use plug-in bonding to fix two insulation modules, or they can use other connection methods to fix two insulation modules. Such adjustments and changes to the specific connection methods of two adjacent insulation modules do not deviate from the principles and scope of this utility model, and should all be limited to the protection scope of this utility model.

[0051] Preferably, such as Figure 2 and Figure 3 As shown, the first side end face of the insulation structure of this utility model is provided with a protrusion 6, and the second side end face of the insulation module is provided with a groove 7. The protrusion 6 is provided with a first connecting hole 8, and the insulation module is provided with a second connecting hole 9 at a position corresponding to the groove 7. The protrusion 6 on one insulation module is inserted into the groove 7 of another insulation module, and the first connecting hole 8 and the second connecting hole 9 are aligned. The insulation module also includes a pin 5, which is inserted into the first connecting hole 8 and the second connecting hole 9 to fix the two insulation modules together.

[0052] By setting protrusions 6 and grooves 7 on the two side end faces of the insulation module respectively, when installing the insulation structure, first insert the groove 7 on one insulation module into the groove 7 on the other insulation module, and then insert the pin 5 into the first connecting hole 8 and the second connecting hole 9 of the two insulation modules, thereby connecting and fixing the two insulation modules.

[0053] For example, such as Figure 3 As shown, a protrusion 6 is provided on the right end face of the insulation module, and a first connecting hole 8 is provided on the top of the protrusion 6. The first connecting hole 8 penetrates the protrusion 6 vertically. A groove 7 is provided on the left end face of the insulation module. A second connecting hole 9 is provided on the top and bottom of the insulation module at positions corresponding to the groove 7. The second connecting hole 9 communicates with the groove 7. When the protrusion 6 on one insulation module is inserted into the groove 7 on another insulation module, the first connecting hole 8 on the protrusion 6 is aligned with the second connecting hole 9 on the other insulation module. Then, the pin 5 is inserted from top to bottom into the first connecting hole 8 and the second connecting hole 9 to fix the two insulation modules together. The length of the pin 5 is basically the same as the height of the insulation module.

[0054] Preferably, such as Figure 1 As shown, the thickness of the heat-reflective layer 2 in the thermal insulation structure of this utility model is 15mm to 25mm.

[0055] For example, those skilled in the art can set the thickness of the heat reflective layer 2 to 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, 21mm, 22mm, 23mm, 24mm or 25mm in practical applications. More preferably, the thickness of the heat reflective layer 2 is 20mm.

[0056] Preferably, the heat-reflective layer 2 of the thermal insulation structure of this utility model includes a ceramic substrate, the inner side of which is connected to the vacuum insulation layer 3, and the outer side of which is provided with a metal film.

[0057] The metal film possesses excellent high-temperature stability, superior infrared reflectivity, and good corrosion resistance. By using a ceramic substrate and depositing a metal film layer on the outer surface of the ceramic substrate, the insulation structure of this invention exhibits better high-temperature resistance, corrosion resistance, and higher reflectivity. Preferably, an electroplating method is used to coat the outer surface of the ceramic substrate with a metal film.

[0058] Preferably, the ceramic substrate of the heat reflective layer 2 of this invention is an alumina ceramic substrate.

[0059] Among them, alumina ceramics have better mechanical strength and high temperature resistance.

[0060] Preferably, the metal film on the ceramic substrate of this invention is a silver film or a gold film.

[0061] Among them, silver or gold films have higher reflectivity and superior high-temperature stability, infrared reflectivity, and corrosion resistance.

[0062] Preferably, such as Figure 1As shown, the thickness of the vacuum insulation layer 3 in the thermal insulation structure of this utility model is 60mm to 100mm.

[0063] For example, those skilled in the art can set the thickness of the vacuum insulation layer 3 to 60mm, 65mm, 70mm, 75mm, 80mm, 85mm, 90mm, 95mm or 100mm in practical applications. More preferably, the thickness of the vacuum insulation layer 3 is 80mm.

[0064] Preferably, the vacuum insulation layer 3 of the thermal insulation structure of this utility model is a vacuum insulation board.

[0065] Vacuum insulation panels are generally composed of two layers of high-barrier materials (such as aluminum foil) and have a sealed cavity inside that is close to a vacuum.

[0066] Preferably, the vacuum insulation panel of the thermal insulation structure of this utility model has a sealed cavity inside, which is filled with a gas adsorbent.

[0067] Among them, the gas adsorbent can be a chemical adsorbent, such as calcium oxide (quicklime) or magnesium oxide, or a physical adsorbent, such as zeolite, open-pore polyurethane or lithium compound.

[0068] Preferably, the thermal insulation felt layer 4 of the thermal insulation structure of this utility model is a nano-aerogel felt layer.

[0069] Among them, nano-aerogel felt is a nanoporous material with silica as the main component, which has extremely low density, ultra-low thermal conductivity and good heat insulation and sound insulation performance.

[0070] Preferably, such as Figure 1 As shown, the thickness of the insulation felt layer 4 in the insulation structure of this utility model is 30mm to 50mm.

[0071] For example, those skilled in the art can set the thickness of the thermal insulation layer 4 to 30mm, 32mm, 35mm, 38mm, 40mm, 42mm, 45mm, 48mm or 50mm in practical applications. More preferably, the thickness of the vacuum insulation layer 3 is 40mm.

[0072] It should be noted that the thermal insulation structure of this utility model is preferably prepared by the sol-gel method, and after being treated by supercritical drying process, a continuous nano-network structure is formed to ensure the high strength and high toughness of the material.

[0073] In addition, after the heat reflective layer 2, the vacuum insulation layer 3 and the heat insulation felt layer 4 are fixedly connected together, they form a heat insulation module. The top surface, bottom surface and two side end surfaces of the heat insulation module are preferably sealed with sealant.

[0074] Those skilled in the art will understand that although some embodiments described herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, any of the claimed embodiments in the claims of this application can be used in any combination.

[0075] The technical solution of this utility model has been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the protection scope of this utility model is obviously not limited to these specific embodiments. Without departing from the principle of this utility model, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the protection scope of this utility model.

Claims

1. A thermal insulation structure, characterized in that, The thermal insulation structure includes an outer heat-reflective layer, a middle vacuum insulation layer, and an inner thermal insulation felt layer. The outer and inner sides of the vacuum insulation layer are connected to the heat-reflective layer and the thermal insulation felt layer, respectively.

2. The thermal insulation structure according to claim 1, characterized in that, The heat reflective layer includes a ceramic substrate, the inner side of which is connected to the vacuum insulation layer, and the outer side of which is provided with a metal film.

3. The thermal insulation structure according to claim 2, characterized in that, The ceramic matrix is ​​an alumina ceramic matrix; and / or The metal film is a silver film or a gold film.

4. The thermal insulation structure according to claim 1, characterized in that, The vacuum insulation layer is a vacuum insulation board.

5. The thermal insulation structure according to claim 4, characterized in that, The vacuum insulation panel has a sealed cavity inside, which is filled with a gas adsorbent.

6. The thermal insulation structure according to claim 1, characterized in that, The thermal insulation felt layer is a nano-aerogel felt layer.

7. The thermal insulation structure according to claim 1, characterized in that, The thickness of the heat-reflective layer is 15 mm to 25 mm; and / or The thickness of the vacuum insulation layer is 60mm to 100mm; and / or The thickness of the thermal insulation felt layer is 30mm to 50mm.

8. The thermal insulation structure according to any one of claims 1 to 7, characterized in that, The insulation structure is configured as a cylindrical structure, which is formed by multiple insulation modules distributed circumferentially along the cylindrical structure.

9. The thermal insulation structure according to claim 8, characterized in that, The insulation module has a protrusion on its first side end face and a groove on its second side end face. The protrusion has a first connecting hole, and the insulation module has a second connecting hole at a position corresponding to the groove. The protrusion on one insulation module is inserted into the groove of another insulation module, and the first connecting hole and the second connecting hole are aligned. The insulation module also includes a pin, which is inserted into the first connecting hole and the second connecting hole to fix the two insulation modules together.

10. A single-crystal silicon Czochralski furnace, characterized in that, The thermal insulation structure includes any one of claims 1 to 9.

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