Thermal insulation cylinder for zone melting and zone melting furnace with thermal insulation cylinder

Abstract

The utility model provides a thermal insulation cylinder for zone melting and a zone melting furnace with the thermal insulation cylinder. The thermal insulation cylinder for zone melting comprises a cylindrical body, a supporting layer is arranged on the outer side of the cylindrical body, an isolating layer is arranged on the inner side of the cylindrical body, and a thermal insulation layer is arranged between the supporting layer and the isolating layer. The device has the beneficial effects that the heat loss is reduced, the heating power requirement is reduced, the heat preservation effect is improved, a uniform temperature gradient is maintained in a melting region, a larger temperature gradient is prevented from being generated between the center and the periphery of the large-diameter single crystal, the thermal stress of the large-diameter single crystal is more uniform, dislocation or edge breakage is reduced, and the production efficiency is improved. And the growth stability and the finished product quality of monocrystalline silicon can be improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of zone melting crystal growth equipment, in particular to a zone melting heat preservation tube and a zone melting furnace provided with the heat preservation tube. Background Art

[0002] During the production of zone-melting silicon single crystals, an insulation cylinder is installed within the zone furnace to maintain the temperature of the melting zone in order to maintain a uniform temperature gradient and promote high-quality single crystal growth. In the prior art, the insulation cylinder is typically a single-layer cylindrical structure made of copper. When producing large-diameter single crystals, the existing insulation cylinders have poor insulation performance and rapid heat dissipation, which can easily lead to heat loss. The large diameter of the single crystal creates a large temperature gradient between the center and periphery of the single crystal, resulting in uneven thermal stress distribution in the single crystal, which can easily cause dislocations or edge breakage in the single crystal. Utility Model Content

[0003] In order to solve the above technical problems, the utility model provides an insulation tube for zone melting and a zone melting furnace equipped with the insulation tube, which effectively solves the problem that the insulation tube has poor insulation effect and easily causes heat loss, and overcomes the shortcomings of the existing technology.

[0004] The technical solution adopted by the utility model is: a zone melting insulation cylinder, comprising a cylindrical body, a support layer is provided on the outer side of the cylindrical body, an isolation layer is provided on the inner side of the cylindrical body, and an insulation layer is provided between the support layer and the isolation layer.

[0005] Furthermore, the thermal insulation layer is configured as a single-layer structure.

[0006] Furthermore, the thermal insulation layer is configured as a multi-layer structure.

[0007] Furthermore, the thermal insulation layer is configured as a double-layer structure, including a first thermal insulation layer and a second thermal insulation layer, wherein the first thermal insulation layer is disposed close to the isolation layer, and the second thermal insulation layer is disposed close to the support layer.

[0008] Furthermore, the first thermal insulation layer is configured as a graphite felt thermal insulation layer.

[0009] Furthermore, the second thermal insulation layer is configured as a silicate thermal insulation layer.

[0010] Furthermore, the isolation layer is configured as a quartz glass layer.

[0011] Furthermore, the support layer is configured as a copper layer.

[0012] Furthermore, a cooling water channel is provided outside the support layer.

[0013] The utility model also provides a zone melting furnace, comprising the zone melting heat preservation tube as described above.

[0014] The advantages and positive effects of the present invention are as follows: due to the adoption of the above technical solution, heat loss is reduced, heating power requirements are lowered, insulation effect is improved, a uniform temperature gradient is maintained in the melting zone, a large temperature gradient is avoided between the center and periphery of a large-diameter single crystal, the thermal stress of the large-diameter single crystal is made more uniform, the occurrence of dislocations or broken edges is reduced, and it helps to improve the stability of single crystal silicon growth and the quality of the finished product. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a front view of a zone melting insulation cylinder according to an embodiment of the present utility model.

[0016] Figure 2 It is a top view of a zone melting insulation cylinder according to an embodiment of the present utility model.

[0017] Figure 3 It is a front view of a zone melting insulation cylinder according to another embodiment of the present invention.

[0018] Figure 4 It is a top view of a zone melting insulation cylinder according to another embodiment of the present invention.

[0019] In the figure: 1. Support layer; 2. Isolation layer; 3. Insulation layer; 4. First insulation layer; 5. Second insulation layer; 6. Cooling water channel; 7. Water inlet; 8. Water outlet. DETAILED DESCRIPTION

[0020] The embodiment of the present utility model provides a zone melting heat preservation tube and a zone melting furnace provided with the heat preservation tube. The embodiment of the present utility model is described below with reference to the accompanying drawings.

[0021] In the description of the embodiments of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "top", "bottom", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of the present invention, it should be noted that, unless otherwise clearly stipulated and limited, the terms "setting" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be a communication between the internal parts of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood based on specific circumstances.

[0022] like Figure 1 and Figure 3As shown, the utility model discloses a kind of zone melting with heat preservation cylinder, including cylindrical body, the outside of cylindrical body is equipped with support layer 1, for supporting protection entire cylindrical body, can also play certain heat insulation effect, specific material is not limited, preferably set as copper layer.Cylindrical body's inside is equipped with isolation layer 2, isolation layer 2 not only needs to resist high temperature, also needs to be able to resist and melt material's chemical reaction, keep the cleanliness of melting area, specific material is not limited, preferably set as quartz glass layer.Support layer 1 and isolation layer 2 between being equipped with heat preservation layer, for heat insulation, reduce heat loss, maintain a more stable thermal radiation field.

[0023] In certain embodiments, as shown in Figure 1 Heat preservation layer is set to single-layer structure, i.e. a layer of heat preservation layer 3 is arranged between support layer 1 and isolation layer 2.The material of heat preservation layer 3 needs to have good heat insulation performance, with lower thermal conductivity, and the specific material is not limited, and preferably graphite felt or silicate.

[0024] In certain embodiments, as shown in Figure 3 In order to ensure the heat preservation effect, the heat preservation layer is set to multi-layer structure, i.e. a plurality of heat preservation layers are arranged between the support layer 1 and the isolation layer 2, and the specific number is not limited.

[0025] Preferably, the heat preservation layer is set to a double-layer structure, including a first heat preservation layer 4 and a second heat preservation layer 5, the first heat preservation layer 4 is arranged close to the isolation layer 2, and the second heat preservation layer 5 is arranged close to the support layer 1.

[0026] Preferably, the first heat preservation layer 4 is set to a graphite felt heat preservation layer, and the second heat preservation layer 5 is set to a silicate heat preservation layer. The graphite felt heat preservation layer has lower thermal conductivity, can effectively reduce heat loss, and keep the temperature of the melting area stable. The silicate heat preservation material is a closed pore network structure material connected by a solid matrix, which is made of a special non-metallic mineral as a base material, a certain amount of auxiliary raw materials and fillers, and certain chemical additives by adopting new processes and technologies. It has low thermal conductivity, small heat loss, and small material thickness, and is non-toxic, does not pollute the environment, and does not corrode equipment, which is an ideal heat preservation material. The second heat preservation layer 5 made of silicate material can further prevent heat transfer to the external environment, further reduce heat loss, and ensure the heat preservation effect.

[0027] Preferably, as shown in Figure 2 And Figure 4 The support layer 1 is externally provided with a cooling water channel 6. The cooling water channel 6 is annularly sleeved outside the support layer 1 and is fixedly connected with the support layer 1. The cooling water channel 6 is provided with a water inlet 7 and a water outlet 8, and the specific position of the cooling water channel 6 is not limited, which can be sleeved on the top, middle or bottom of the support layer 1. By arranging the cooling water channel 6, the temperature of the thermal field can be controlled by adjusting the cooling water flow while heat preservation.

[0028] A zone melting furnace comprises the above-mentioned zone melting insulation cylinder, which is used for maintaining the temperature of the melting zone.

[0029] Example 1: Figure 1 and Figure 2 As shown, a zone melting insulation cylinder comprises a cylindrical body. A support layer 1, specifically a copper layer, is provided on the outside of the cylindrical body. An isolation layer 2, specifically a quartz glass layer, is provided on the inside of the cylindrical body. An insulation layer 3, specifically a single-layer graphite felt layer, is provided between the support layer 1 and the isolation layer 2. An annular cooling waterway 6 is provided around the outside of the support layer 1 and welded to the top of the support layer 1. The cooling waterway 6 is provided with a water inlet 7 and a water outlet 8.

[0030] Example 2: A zone melting insulation cylinder comprises a cylindrical body. A support layer 1, specifically a copper layer, is provided on the outside of the cylindrical body. An isolation layer 2, specifically a quartz glass layer, is provided on the inside of the cylindrical body. An insulation layer 3, specifically a silicate layer, is provided between the support layer 1 and the isolation layer 2. An annular cooling water channel 6 is provided around the outside of the support layer 1 and welded to the center of the support layer 1. The cooling water channel 6 is provided with a water inlet 7 and a water outlet 8.

[0031] Example 3: Figure 3 and Figure 4 As shown, a zone melting insulation cylinder includes a cylindrical body with a support layer 1, specifically a copper layer, disposed on the outside of the cylindrical body and an isolation layer 2, specifically a quartz glass layer, disposed on the inside of the cylindrical body. An insulation layer is disposed between the support layer 1 and the isolation layer 2. The insulation layer has a double-layer structure, including a first insulation layer 4 and a second insulation layer 5. The first insulation layer 4 is disposed adjacent to the isolation layer 2, while the second insulation layer 5 is disposed adjacent to the support layer 1. The first insulation layer 4 is configured as a graphite felt insulation layer, while the second insulation layer 5 is configured as a silicate insulation layer. An annular cooling waterway 6 is provided on the outside of the support layer 1 and is welded to the bottom of the support layer 1. The cooling waterway 6 is provided with a water inlet 7 and a water outlet 8.

[0032] The advantages and positive effects of the utility model are:

[0033] 1. By setting up an insulation layer, especially a double-layer insulation layer, heat loss is reduced, heating power requirements are lowered, and insulation effect is improved. A uniform temperature gradient is maintained in the melting zone, avoiding a large temperature gradient between the center and periphery of a large-diameter single crystal. The thermal stress of the large-diameter single crystal is made more uniform, and the occurrence of dislocations or broken edges is reduced, which helps to improve the stability of single crystal silicon growth and the quality of the finished product.

[0034] 2. By setting up an isolation layer, it is possible to prevent the heat preservation tube from chemically reacting with the molten material, thereby ensuring the purity of the molten zone and further ensuring the quality of the single crystal.

[0035] The embodiments of the present application are described in detail above, but the content described is only the preferred embodiments of the present application, and cannot be considered as limiting the scope of the embodiments of the present application. Any equivalent changes and improvements made within the scope of the present application should still belong to the patent coverage of the present application.

Claims

1. A zone melting insulation cylinder, comprising a cylindrical body, characterized in that: A support layer is provided on the outer side of the cylindrical body, an isolation layer is provided on the inner side of the cylindrical body, a heat preservation layer is provided between the support layer and the isolation layer, and a cooling water channel is provided outside the support layer.

2. The zone melting insulation cylinder according to claim 1, characterized in that: The thermal insulation layer is configured as a single-layer structure.

3. The zone melting insulation cylinder according to claim 1, characterized in that: The thermal insulation layer is configured as a multi-layer structure.

4. The zone melting insulation cylinder according to claim 3, characterized in that: The thermal insulation layer is configured as a double-layer structure, including a first thermal insulation layer and a second thermal insulation layer. The first thermal insulation layer is configured close to the isolation layer, and the second thermal insulation layer is configured close to the support layer.

5. The zone melting insulation cylinder according to claim 4, characterized in that: The first thermal insulation layer is configured as a graphite felt thermal insulation layer.

6. The zone melting insulation cylinder according to claim 5, characterized in that: The second thermal insulation layer is configured as a silicate thermal insulation layer.

7. A zone melting insulation cylinder according to any one of claims 1 to 6, characterized in that: The isolation layer is configured as a quartz glass layer.

8. The zone melting insulation cylinder according to claim 7, characterized in that: The supporting layer is configured as a copper layer.

9. A zone melting furnace, characterized in that: It comprises the zone melting insulation cylinder as described in any one of claims 1-8.

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