Thermal insulation barrel device on single crystal furnace

Abstract

The utility model provides an upper thermal insulation barrel device of a single crystal furnace, which can at least partially solve the problem that an upper thermal insulation barrel is damaged due to expansion of a soft felt shrinkage graphite upper protector when the existing thermal insulation barrel is used in the single crystal furnace. The upper thermal insulation barrel device of the single crystal furnace comprises an upper graphite thermal insulation barrel, longitudinal graphite strips, transverse reinforcing graphite strips and a soft felt, concave pit parts are formed in a circle of the outer wall of the graphite upper heat insulation barrel at intervals; the concave pit parts are matched with the longitudinal graphite strips in size, the longitudinal graphite strips can be inserted into the concave pit parts, the inserted longitudinal graphite strips are provided with protrusions on the basis of the outer wall of the upper graphite heat preservation barrel, the protrusions of the longitudinal graphite strips increase the expandable space of the upper graphite heat preservation barrel and the retractable space of the soft felt, and the damage rate of the upper graphite heat preservation barrel is reduced; the transverse reinforcing graphite strips are provided with bulges based on the outer wall of the graphite upper insulation barrel; the transverse reinforcing graphite strips can prevent a gap between the graphite upper heat preservation barrel and the soft felt from dissipating heat outwards, and the heat preservation performance of a thermal field is not affected.

Description

Technical Field

[0001] The utility model belongs to the technical field of single crystal silicon manufacturing, and particularly relates to a device for an upper heat preservation barrel of a single crystal furnace. Background Art

[0002] The single crystal furnace consists of a heater and a heat preservation part to form its thermal field system. The single crystal furnace heats and melts raw materials by its own resistance heating. The heat preservation part includes bottom heat preservation, top heat preservation, and upper, middle, and lower heat preservation barrels.

[0003] In most cases, the heat preservation barrel includes a support layer and a heat preservation layer. The support layer plays a supporting role and is generally made of graphite material; the heat preservation layer plays a heat preservation role and is generally made of heat preservation carbon felt or carbon fiber material. Usually, its structure is that the inner layer is the support layer and the outer layer is the heat preservation layer, and there is also a heat preservation barrel with the inner layer being the heat preservation layer and the outer layer being the support layer. In addition, there is also a heat preservation barrel formed by integrating graphite material and heat preservation material. Whether it is a heat preservation barrel formed into a multi-layer structure or an integrated structure, and regardless of whether the heat preservation layer is located in the inner layer or the outer layer, the disadvantage of the existing heat preservation barrel is that the heat reflectivity of the material on the inner side of the heat preservation barrel is low. Therefore, the heat radiated from the heater, crucible, and the surface of the silicon melt in the crucible to the heat preservation barrel cannot be effectively reflected. Especially, a large amount of heat is radiated from the heater to the heat preservation barrel. To maintain the temperature of the heater, it is necessary to increase the power of the heater, resulting in a large amount of heat waste.

[0004] In the prior art, the heat preservation barrel is generally wrapped with soft felt. However, during actual use, due to the expansion coefficient, the graphite upper heat preservation barrel expands when heated, while the soft felt shrinks when heated. The shrinkage of the soft felt and the expansion of the graphite upper heat preservation barrel will damage the device for the upper heat preservation barrel of the single crystal furnace, and most of the current upper heat preservation barrels are spliced, which is more likely to cause the joints to break. Summary of the Utility Model

[0005] The purpose of the utility model is to increase the expandable space of the graphite upper heat preservation barrel and the shrinkable space of the soft felt, and reduce the damage rate of the graphite upper heat preservation barrel.

[0006] To solve the above technical problems, the utility model adopts the following technical solutions:

[0007] On the one hand, a device for an upper heat preservation barrel of a single crystal furnace, characterized in that it includes a graphite upper heat preservation barrel and a longitudinal graphite bar; the graphite upper heat preservation barrel includes a concave part, the concave part is in the middle of the outer wall of the graphite upper heat preservation barrel, and the length of the concave part is less than the height of the graphite upper heat preservation barrel; the concave part is matched with the longitudinal graphite bar in size, and the longitudinal graphite bar can be inserted into the concave part, and the inserted longitudinal graphite bar has a protrusion based on the outer wall of the graphite upper heat preservation barrel.

[0008] On the other hand, the upper and lower circumferential outer walls of the upper thermal insulation barrel made of graphite are both horizontally reinforced graphite bars. The horizontally reinforced graphite bars are located on the upper and lower sides of the vertically reinforced graphite bars, and the horizontally reinforced graphite bars have protrusions based on the outer wall of the upper thermal insulation barrel made of graphite.

[0009] Preferably, a plurality of concave portions are arranged at intervals on the outer wall of the upper thermal insulation barrel made of graphite, and the concave portions correspond to the vertically reinforced graphite bars one by one.

[0010] Preferably, the protrusion sizes of the horizontally reinforced graphite bars and the vertically reinforced graphite bars are the same, and the protrusion size is A. The value of A ranges from 1 mm to 2 mm, and 1 mm or 1.5 mm or 2 mm can be taken.

[0011] Preferably, the upper thermal insulation barrel device of the single crystal furnace further includes a soft felt, and the soft felt wraps around the protrusions of the horizontally reinforced graphite bars and the vertically reinforced graphite bars.

[0012] The beneficial effects of the present utility model are as follows:

[0013] In this device, after the vertically reinforced graphite bars are inserted into the concave portions, when the vertically reinforced graphite bars are damaged, it is convenient to disassemble and replace the vertically reinforced graphite bars; the protrusions of the vertically reinforced graphite bars increase the gap between the upper thermal insulation barrel made of graphite and the soft felt, and also make the soft felt tightly wrap around the upper thermal insulation barrel made of graphite, thereby increasing the expandable space of the upper thermal insulation barrel made of graphite and the shrinkable space of the soft felt, and reducing the damage rate of the upper thermal insulation barrel made of graphite. The horizontally reinforced graphite bars not only enhance the heat insulation strength of the upper thermal insulation barrel made of graphite, but also the soft felt wraps around the protrusions of the horizontally reinforced graphite bars and the vertically reinforced graphite bars. The horizontally reinforced graphite bars can block the heat dissipation of the gap between the upper thermal insulation barrel made of graphite and the soft felt, and will not affect the heat field heat insulation performance. Description of the Drawings

[0014] The drawings described herein are used to provide a further understanding of the embodiments of the present utility model, and constitute a part of this application, but do not constitute a limitation to the embodiments of the present utility model.

[0015] Figure 1 It is a schematic diagram of the upper thermal insulation barrel made of graphite of the present utility model.

[0016] Figure 2 It is a schematic side view of the overall structure of the present utility model.

[0017] Figure 3 It is a schematic diagram of the vertically reinforced graphite bars of the present utility model.

[0018] Figure 4 It is a schematic diagram of the overall structure of the present utility model.

[0019] Figure 5 It is a cross-sectional view of the present utility model.

[0020] Figure 6This is a cross-sectional view of the present utility model without a horizontal graphite strip.

[0021] Figure 7 This is a cross-sectional view of the present utility model with a horizontal graphite strip.

[0022] The corresponding component names for the respective reference numerals in the figure are: 1, upper graphite heat-insulating barrel; 11, pit portion; 2, longitudinal graphite strip; 3, horizontal reinforcing graphite strip; 4, soft felt. Detailed implementation manners

[0023] To enable those skilled in the art to better understand the technical solution of the present utility model, the present utility model will be further described in detail below with reference to the accompanying drawings and specific implementation manners.

[0024] Embodiment 1

[0025] As Figure 1-4 shown, a device for the upper graphite heat-insulating barrel of a single crystal furnace includes an upper graphite heat-insulating barrel 1, a horizontal reinforcing graphite strip 3, and a soft felt 4. A plurality of pit portions 11 are arranged at intervals in a circle on the outer wall of the upper graphite heat-insulating barrel 1; the soft felt 4 is wrapped around the outer wall of the upper graphite heat-insulating barrel 1; the upper and lower circumferences of the upper graphite heat-insulating barrel 1 are both horizontal reinforcing graphite strips 3.

[0026] As Figure 5 shown, the device for the upper graphite heat-insulating barrel of a single crystal furnace further includes a longitudinal graphite strip 2; when heated, the outer wall of the upper graphite heat-insulating barrel 1 expands radially outward, and the inner wall of the soft felt 4 contracts radially inward (see the dotted arrow in Figure 5 for illustration), then the longitudinal graphite strip 2 is squeezed from both inside and outside and is easily damaged; since the pit portion 11 matches the longitudinal graphite strip 2 in size, the longitudinal graphite strip 2 can be inserted into the pit portion 11, so when the longitudinal graphite strip 2 is damaged, it is convenient for the staff to disassemble and replace the longitudinal graphite strip 2; after the longitudinal graphite strip 2 is inserted, there is a protrusion on the outer wall of the upper graphite heat-insulating barrel 1, and this protrusion increases the gap between the upper graphite heat-insulating barrel 1 and the soft felt 4, and also makes the soft felt 4 tightly wrap the upper graphite heat-insulating barrel 1, thereby increasing the expandable space of the upper graphite heat-insulating barrel 1 and the shrinkable space of the soft felt 4;

[0027] As Figure 6 、 7 shown, Figure 6 This is a cross-sectional view of the device for the upper graphite heat-insulating barrel of a single crystal furnace without the horizontal reinforcing graphite strip 3. It can be seen that when there is no horizontal reinforcing graphite strip 3, there is a large gap between the upper graphite heat-insulating barrel 1 and the soft felt 4, then heat will be dissipated from the gap between the upper graphite heat-insulating barrel 1 and the soft felt 4 (see the curved arrow in Figure 6 for illustration), which affects the heat preservation performance of the thermal field; Figure 7It is a cross-sectional view of the upper heat-insulating bucket device of a single crystal furnace with a horizontally reinforced graphite strip 3. It can be found that when there is a horizontally reinforced graphite strip 3, the horizontally reinforced graphite strip 3 has a protrusion based on the outer wall of the graphite upper heat-insulating bucket 1. The protrusion size of the horizontally reinforced graphite strip 3 is the same as that of the longitudinally arranged graphite strip 2, and the soft felt 4 wraps around the protrusions of the horizontally reinforced graphite strip 3 and the longitudinally arranged graphite strip 2. The horizontally reinforced graphite strip 3 can block the external heat dissipation through the gap between the graphite upper heat-insulating bucket 1 and the soft felt 4 (see the curved arrow in Figure 7 for illustration), without affecting the heat preservation performance of the thermal field; moreover, since the horizontally reinforced graphite strip 3 is located on the upper and lower sides of the longitudinally arranged graphite strip 2, the heat preservation strength of the graphite upper heat-insulating bucket 1 is enhanced.

[0028] As shown in Figure 1 , the graphite upper heat-insulating bucket 1 has a total of 12 pits 11, and the shape of the pits 11 can be a rectangular groove or an arc-shaped groove.

[0029] The shape of the longitudinally arranged graphite strip 2 is determined according to the shape of the pits 11. For example, as shown in Figure 3 , the longitudinally arranged graphite strip 2 is in the shape of a cuboid. The staff only needs to ensure that the longitudinally arranged graphite strip 2 can be stably inserted into the pits 11.

[0030] The protrusion size of the longitudinally arranged graphite strip 2 is 1.5 mm. Through solidworks stress simulation, a 1.5-mm gap between the graphite upper heat-insulating bucket 1 and the soft felt 4 is the optimal state.

[0031] It can be understood that the above embodiments are merely exemplary embodiments adopted to illustrate the principle of the present utility model. However, the present utility model is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention / utility model, and these modifications and improvements are also regarded as the protection scope of the present invention / utility model.

Claims

1. A heat preservation barrel device on a single crystal furnace, characterized in that: The invention comprises a graphite upper heat-insulating barrel (1) and a longitudinal graphite strip (2); the graphite upper heat-insulating barrel (1) comprises a concave portion (11), the concave portion (11) is located in the middle of the outer wall of the graphite upper heat-insulating barrel (1), and the length of the concave portion (11) is less than the height of the graphite upper heat-insulating barrel (1); the size of the concave portion (11) matches that of the longitudinal graphite strip (2), and the longitudinal graphite strip (2) can be inserted into the concave portion (11), and after insertion, the longitudinal graphite strip (2) has a protrusion based on the outer wall of the graphite upper heat-insulating barrel (1).

2. The heat preservation barrel device on a single crystal furnace according to claim 1, characterized in that: It also includes transverse reinforcing graphite strips (3), the upper and lower circumferential outer walls of the graphite upper insulation barrel (1) are both transverse reinforcing graphite strips (3), the transverse reinforcing graphite strips (3) are on the upper and lower sides of the longitudinal graphite strips (2), and the transverse reinforcing graphite strips (3) are protruded based on the outer wall of the graphite upper insulation barrel (1).

3. The heat preservation barrel device on a single crystal furnace according to claim 1, characterized in that: The outer wall of the graphite upper heat-insulating barrel (1) is provided with recessed portions (11) at intervals, and the recessed portions (11) correspond one to one with the longitudinal graphite strips (2).

4. The heat preservation barrel device on a single crystal furnace according to claim 2, characterized in that: The protrusion size of the transverse reinforcing graphite strip (3) and the longitudinal graphite strip (2) is the same, and the protrusion size is A.

5. The heat preservation barrel device on a single crystal furnace according to claim 4, characterized in that: The A is 1mm-2mm.

6. The heat preservation barrel device on a single crystal furnace according to claim 2, characterized in that: It also includes a soft felt (4), which is wrapped around the protrusions of the transverse reinforcing graphite strips (3) and the protrusions of the longitudinal graphite strips (2).

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