Middle shaft sheath for single crystal furnace

Abstract

The utility model discloses a centre shaft sheath for a single crystal furnace, which comprises an upper centre shaft sheath, a lower centre shaft sheath and a positioning ring which are sequentially connected from top to bottom, and the upper centre shaft sheath, the lower centre shaft sheath and the positioning ring are respectively connected in a split detachable manner to form an integral sheath and are sleeved outside a centre shaft of the single crystal furnace. A slot is formed in the inner wall of the bottom of the upper middle shaft sheath, and the top of the lower middle shaft sheath is inserted into the slot in the bottom of the upper middle shaft sheath, so that the upper middle shaft sheath is connected with the lower middle shaft sheath. A step groove is formed in the middle of the positioning ring, and the bottom of the lower middle shaft sheath is connected in the counter bore step groove in the middle of the positioning ring, so that the lower middle shaft sheath is connected with the positioning ring. The center shaft sheath adopts a three-section sheath design, so that direct contact between an integrated structure and a furnace bottom can be effectively avoided, high temperature at the upper part is directly conducted to the furnace bottom, and heat conduction is slowed down.

Description

Technical Field

[0001] This utility model belongs to the field of single crystal silicon preparation, specifically relating to a central shaft sleeve for a single crystal furnace. Background Technology

[0002] The central shaft sleeve of a single-crystal furnace is a protective device for the furnace's central shaft. Currently, the thermal field central shaft sleeve is embedded in the insulation layer at the center of the furnace bottom, and is a ring-shaped sleeve fitted around the lower part of the central shaft, completely isolating the furnace bottom insulation layer from the central shaft to prevent the insulation layer and other components from affecting the operation of the central shaft. However, because the existing central shaft sleeve is a one-piece graphite structure with a high thermal conductivity, the lower end of the sleeve is in direct contact with the furnace bottom, allowing heat to easily conduct to the furnace bottom, resulting in heat loss within the furnace. Furthermore, the existing sleeve is a one-piece graphite structure; once damaged by impact during use, it must be scrapped, resulting in high operating costs. Additionally, the gap between the outer insulation felt and the sleeve is a through-hole leading directly to the furnace bottom. If silicon leakage occurs, molten silicon will travel along this gap to the furnace bottom, potentially causing the furnace bottom to be scalded through. If the furnace bottom cooling water leaks out, it can easily lead to a safety accident. Summary of the Invention

[0003] Purpose of this utility model: The technical problem to be solved by this utility model is to provide a central shaft sleeve for a single crystal furnace, which can effectively solve the problems existing in the existing device, improve the heat preservation performance of the furnace bottom, reduce production and use costs, and improve the safety of use.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0005] A central shaft sleeve for a single crystal furnace includes an upper central shaft sleeve, a lower central shaft sleeve, and a positioning ring connected sequentially from top to bottom. The three parts are connected in a separate and detachable manner to form an integral sleeve, which is fitted onto the outside of the central shaft of the single crystal furnace.

[0006] Furthermore, the inner wall of the bottom of the upper central shaft sleeve is provided with a slot, and the top of the lower central shaft sleeve is inserted into the slot at the bottom of the upper central shaft sleeve, thereby realizing the connection between the upper central shaft sleeve and the lower central shaft sleeve.

[0007] Furthermore, a stepped groove is provided in the middle of the positioning ring, and the bottom of the lower central shaft sleeve is received in the stepped groove of the countersunk hole in the middle of the positioning ring, thereby realizing the connection between the lower central shaft sleeve and the positioning ring.

[0008] Furthermore, the central shaft sleeve for the single crystal furnace also includes a graphite felt insulation layer, a solid felt insulation layer, and an insulation layer protective plate, which are sequentially fitted onto the outside of the integral sleeve composed of the upper central shaft sleeve, the lower central shaft sleeve, and the positioning ring from bottom to top.

[0009] Furthermore, the bottom of the graphite felt insulation layer is flush with the bottom of the positioning ring; the top of the graphite felt insulation layer is not higher than the bottom of the upper central shaft sleeve.

[0010] Furthermore, the bottom of the solid felt insulation layer is lower than the bottom of the upper central shaft sleeve, and the top of the solid felt insulation layer does not exceed the top of the upper central shaft sleeve.

[0011] Furthermore, the insulation layer protective plate does not extend beyond the top of the upper central shaft sleeve.

[0012] Preferably, the upper central shaft sleeve is made of graphite material.

[0013] Preferably, the lower central shaft sleeve is made of carbon carbon material.

[0014] Preferably, the positioning ring is made of ceramic material.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] (1) The central shaft sleeve of the single crystal furnace of this utility model adopts a split structure design, and the combination of carbon, ceramic and graphite materials effectively slows down the heat conduction to the furnace bottom, reduces heat loss and improves the heat preservation of the furnace bottom.

[0017] (2) The central shaft sleeve for the single crystal furnace of this utility model adopts a split structure design. If a single part is damaged by a bump, it can be replaced separately, avoiding the need to replace the whole part and reducing the cost of using graphite parts.

[0018] (3) The central shaft sleeve of the single crystal furnace of this utility model adopts a three-section sleeve design, which can effectively avoid the direct contact between the integrated structure and the furnace bottom, and the high temperature at the top is directly conducted to the furnace bottom, thus slowing down the heat conduction.

[0019] (4) The recessed combination installation design of the central shaft sleeve reinforcement felt insulation layer of the single crystal furnace of this utility model effectively seals the gaps and prevents the silicon liquid from flowing directly down to the bottom of the furnace through the gap between the sleeve and the insulation layer when silicon leakage occurs, thus avoiding the furnace bottom being scalded through and avoiding the occurrence of safety accidents. Attached Figure Description

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages of the present invention in the above and / or other aspects will become clearer.

[0021] Figure 1 This is a schematic diagram of the three-section split structure of the central shaft sleeve for the single crystal furnace.

[0022] Figure 2 This is a schematic diagram of the overall structure of the central shaft sleeve used in the single crystal furnace.

[0023] In the diagram, the various reference numerals represent:

[0024] 1-Upper central shaft sheath; 2-Lower central shaft sheath; 3-Positioning ring; 4-Central shaft; 5-Insulation layer protective plate; 6-Fixed felt insulation layer; 7-Graphite felt insulation layer. Detailed Implementation

[0025] The present invention can be better understood from the following embodiments.

[0026] The structures, proportions, and sizes shown in the accompanying drawings are merely for illustrative purposes and to aid those skilled in the art. They are not intended to limit the scope of this invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, provided they do not affect the effectiveness or purpose of this invention, should still fall within the scope of the technical content disclosed in this invention. Furthermore, terms such as "upper," "lower," "front," "rear," and "middle" used in this specification are merely for clarity and not intended to limit the scope of this invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of this invention.

[0027] Combination Figure 1 and Figure 2 The central shaft sleeve for the single crystal furnace of this utility model includes an upper central shaft sleeve 1, a lower central shaft sleeve 2 and a positioning ring 3 connected sequentially from top to bottom. The three are connected in a split and detachable manner to form an integral sleeve, which is sleeved on the outside of the central shaft 4 of the single crystal furnace.

[0028] The upper central shaft sleeve 1 has a slot on its bottom inner wall, and the top of the lower central shaft sleeve 2 is inserted into the slot at the bottom of the upper central shaft sleeve 1, thereby connecting the upper central shaft sleeve 1 and the lower central shaft sleeve 2.

[0029] The positioning ring 3 has a stepped groove in the middle, and the bottom of the lower central shaft sleeve 2 is supported in the stepped groove of the countersunk hole in the middle of the positioning ring 3, thereby realizing the connection between the lower central shaft sleeve 2 and the positioning ring 3.

[0030] The central shaft sleeve for a single crystal furnace also includes a graphite felt insulation layer 7, a solid felt insulation layer 6, and an insulation layer protective plate 5, which are sequentially fitted from bottom to top onto the outside of the integral sleeve consisting of the upper central shaft sleeve 1, the lower central shaft sleeve 2, and the positioning ring 3.

[0031] The bottom of the graphite felt insulation layer 7 is flush with the bottom of the positioning ring 3; the top of the graphite felt insulation layer 7 is not higher than the bottom of the upper central shaft sleeve 1.

[0032] The bottom of the solid felt insulation layer 6 is lower than the bottom of the upper central shaft sleeve 1, and the top of the solid felt insulation layer 6 does not exceed the top of the upper central shaft sleeve 1.

[0033] The insulation layer protective plate 5 shall not exceed the top of the upper central axis protective sleeve 1.

[0034] In this embodiment, the upper central shaft sleeve 1 is made of graphite material.

[0035] In this embodiment, the lower central shaft sleeve 2 is made of carbon carbon material.

[0036] In this embodiment, the positioning ring 3 is made of ceramic material.

[0037] The assembly method for the central shaft sleeve of the single crystal furnace is as follows: First, place the positioning ring 3 at the bottom. Then, place the lower central shaft sleeve 2 into the countersunk hole of the positioning ring 3. Next, install the graphite felt insulation layer 7 and the solid felt insulation layer 6 in sequence. Place the upper central shaft sleeve 1 with the countersunk hole end into the countersunk hole of the solid felt insulation layer 6. The upper end of the lower central shaft sleeve 2 is completely wrapped by the countersunk hole of the upper central shaft sleeve 1. Finally, install the insulation layer guard plate 5 above the solid felt insulation layer 6. Insert the central shaft 4 into the circular space formed by the upper central shaft sleeve 1, the lower central shaft sleeve 2, and the positioning ring 3 (e.g., ...). Figure 2 ).

[0038] The central shaft sleeve for this single crystal furnace has the following characteristics:

[0039] The upper central shaft sleeve 1 and the lower central shaft sleeve 2 adopt a split structure design, which effectively avoids direct contact between the integrated structure and the furnace bottom, preventing the high temperature at the top from being directly conducted to the furnace bottom, thus slowing down heat conduction. The lower central shaft sleeve 2 is made of carbon-carbon material, and the positioning ring 3 is made of ceramic material. Both have lower thermal conductivity than the graphite material of the upper central shaft sleeve 1, further slowing down the conduction of heat from the top to the lower central shaft sleeve 2 and reducing heat loss.

[0040] The upper central shaft sleeve 1 and the lower central shaft sleeve 2 adopt a split structure design. If a single part is damaged by a bump, it can be replaced individually, avoiding the need to replace the whole part and reducing the cost of using graphite parts.

[0041] The lower part of the upper central shaft sheath 1 contacts the bottom of the countersunk hole of the solid felt insulation layer 6 (e.g.) Figure 2 The gap between the upper central shaft sleeve 1 and the solid felt insulation layer 6 is completely sealed at the bottom, which can effectively prevent the molten silicon from flowing directly down to the furnace bottom through the gap between the central shaft sleeve and the insulation layer in the event of silicon leakage, causing the furnace bottom to be scalded through and resulting in a safety accident.

[0042] This utility model provides a concept and method for a central shaft sleeve for a single crystal furnace. There are many methods and approaches to implement this technical solution; the above description is only a preferred embodiment of this utility model. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of this utility model, and these improvements and modifications should also be considered within the scope of protection of this utility model. All components not explicitly stated in this embodiment can be implemented using existing technology.

Claims

1. A central shaft sleeve for a single crystal furnace, characterized in that, It comprises upper middle shaft sleeve (1), lower middle shaft sleeve (2) and positioning ring (3) connected in sequence from top to bottom, which are connected in a detachable manner to form an integral sleeve.

2. The shaft protecting sleeve for a single crystal furnace according to claim 1, wherein The upper middle shaft sleeve (1) is provided with a slot in the inner wall of the bottom, and the top of the lower middle shaft sleeve (2) is inserted into the slot in the bottom of the upper middle shaft sleeve (1), so as to realize the connection of the upper middle shaft sleeve (1) and the lower middle shaft sleeve (2).

3. The shaft protecting sleeve for a single crystal furnace according to claim 1, wherein The positioning ring (3) is provided with a stepped groove in the middle, and the bottom of the lower middle shaft sleeve (2) is received in the stepped groove in the middle of the positioning ring (3), so as to realize the connection of the lower middle shaft sleeve (2) and the positioning ring (3).

4. The shaft protecting sleeve for a single crystal furnace according to claim 1, wherein It also comprises graphite felt heat insulation layer (7), fixed felt heat insulation layer (6) and heat insulation layer guard plate (5) which are sequentially sleeved outside the integral sleeve composed of the upper middle shaft sleeve (1), the lower middle shaft sleeve (2) and the positioning ring (3).

5. The shaft protecting sleeve for a single crystal furnace according to claim 4, wherein The bottom of the graphite felt heat insulation layer (7) is flush with the bottom of the positioning ring (3), and the top of the graphite felt heat insulation layer (7) is not higher than the bottom of the upper middle shaft sleeve (1).

6. The shaft protecting sleeve for a single crystal furnace according to claim 4, wherein The bottom of the fixed felt heat insulation layer (6) is lower than the bottom of the upper middle shaft sleeve (1), and the top of the fixed felt heat insulation layer (6) is not higher than the top of the upper middle shaft sleeve (1).

7. The central shaft jacket for a single crystal furnace according to claim 4, wherein The heat insulation layer guard plate (5) is not higher than the top of the upper middle shaft sleeve (1).

8. The central shaft jacket for a single crystal furnace according to claim 1, wherein The upper middle shaft sleeve (1) is made of graphite material.

9. The central shaft jacket for a single crystal furnace according to claim 1, wherein The lower middle shaft sleeve (2) is made of carbon-carbon material.

10. The central shaft jacket for a single crystal furnace according to claim 1, wherein The positioning ring (3) is made of ceramic material.

Images