A corrosion-resistant auxiliary furnace for a Czochralski single crystal furnace

Abstract

This invention relates to the field of single crystal furnace technology, specifically to a corrosion-resistant Czochralski single crystal furnace auxiliary furnace, comprising an auxiliary furnace body, a drive mechanism, and several inner lining plates arranged along the inner circumference of the auxiliary furnace body. The inner lining plates enclose a channel for pulling single crystal silicon pillars. The inner lining plates slide in conjunction with a rotary disk and a bearing ring, and under the action of the drive mechanism, they deflect synchronously and move radially, thereby achieving continuous adjustment of the inner aperture of the auxiliary furnace. An interlayer cavity is formed between the inner lining plates and the auxiliary furnace body. Inert gas is introduced into the interlayer cavity, and a directional gas curtain is formed through the gas guide channels and gas distribution strips inside the inner lining plates to isolate and protect against corrosive gases. The inner lining plates have a detachable structure, effectively isolating the auxiliary furnace body in high-temperature corrosive environments and facilitating replacement. This auxiliary furnace has the advantages of a large aperture adjustment range, strong resistance to atmospheric corrosion, convenient maintenance, and adaptability to pulling single crystal silicon pillars of various specifications.

Description

Technical Field

[0001] This invention relates to the field of single crystal furnace technology, specifically to a corrosion-resistant Czochralski single crystal furnace auxiliary furnace. Background Technology

[0002] Czochralski furnaces are widely used in the preparation of single-crystal silicon materials. Their auxiliary furnaces are typically located upstream or to the side of the main furnace, serving as raw material feeders, atmosphere buffers, and isolation for the growth environment. The stability, cleanliness, and corrosion resistance of the auxiliary furnace's internal structure directly affect the pulling quality of the single-crystal silicon pillars and the long-term operational reliability of the equipment.

[0003] In existing Czochralski single crystal furnace auxiliary furnaces, fixed inner lining structures are commonly used as isolation and protection components. These linings are typically fixedly installed along the inner wall of the auxiliary furnace, with the inner diameter determined during the design phase. Their structural form is often a monolithic cylindrical liner or a cylindrical structure formed by splicing several fixed liner plates. For example, some auxiliary furnaces use quartz liner tubes or ceramic bushings fixed inside the metal furnace body to isolate the high-temperature atmosphere from the metal shell; other technical solutions use multiple liner plates fixedly connected along the circumference to form a channel structure of fixed diameter to meet the pulling requirements of single-specification single crystal silicon pillars.

[0004] However, the aforementioned fixed liner structure still has significant shortcomings in practical applications. First, because the liner pore size is not adjustable, when producing single-crystal silicon pillars of different diameters, it is often necessary to replace the entire auxiliary furnace or the entire liner structure. This is not only complex to operate but also results in long downtime, making it difficult to meet the current production needs of multiple specifications and small batches. Second, the fixed liner is exposed to high temperature and corrosive atmosphere for extended periods. Once corrosion, cracks, or localized damage occurs, it is usually difficult to replace the liner locally, which can easily lead to further corrosion extending to the auxiliary furnace metal body and shortening the overall service life of the equipment.

[0005] In addition, existing auxiliary furnaces rely on a single inert gas filling or a simple gas flow method for atmosphere protection, lacking targeted isolation measures for the lining surface and structural gaps. Corrosive gases are prone to stagnation and condensation or deposition on the lining surface, joints, or local low-flow-rate areas, thereby aggravating the corrosion and aging of the lining material and further affecting the operational stability of the auxiliary furnace and the cleanliness of the single crystal growth environment.

[0006] Therefore, there is an urgent need for a Czochralski single crystal furnace auxiliary furnace structure that can achieve adjustable lining aperture and removable lining without changing the overall auxiliary furnace structure, while also having atmosphere and gas curtain isolation and protection capabilities, in order to overcome the problems of poor adaptability, high maintenance costs and insufficient resistance to atmosphere corrosion of the existing fixed lining. Summary of the Invention

[0007] This invention aims to solve the problems of existing Czochralski single crystal furnace auxiliary furnaces, which generally adopt a fixed liner structure, have non-adjustable inner hole diameter, are difficult to adapt to the pulling requirements of single crystal silicon pillars of different diameters, and suffer from liner damage, high maintenance costs, and insufficient resistance to gas corrosion in high-temperature corrosive atmospheres. This invention provides a corrosion-resistant Czochralski single crystal furnace auxiliary furnace. This auxiliary furnace, through an adjustable liner structure and atmosphere-gas curtain collaborative isolation design, ensures the stability of single crystal pulling while achieving flexible adjustment of the inner hole diameter and long-term protection of the auxiliary furnace body.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a corrosion-resistant Czochralski single crystal furnace auxiliary furnace, comprising an auxiliary furnace body, a drive mechanism, and several inner lining plates arranged inside the auxiliary furnace body. The several inner lining plates are arranged along the circumference of the auxiliary furnace body and enclose to form a channel structure for pulling single crystal silicon pillars. The drive mechanism and the inner lining plates form a linkage adjustment relationship to achieve adjustable aperture of the auxiliary furnace inner hole.

[0009] In a preferred embodiment, the configuration is further as follows: a bearing ring is fixedly installed on the inner side of the auxiliary furnace body; the bottom end of the inner lining plate is slidably fitted into an arc groove provided on the surface of the bearing ring via a sliding pin; and the top end of the inner lining plate is slidably fitted into a guide groove provided on the bottom surface of the rotary disc driven by the drive mechanism via a sliding strip. Through the geometrical difference between the guide groove and the arc groove, the inner lining plate simultaneously deflects and slides radially during the rotation of the rotary disc, thereby changing the size of the inner channel aperture formed by the enclosed space of several inner lining plates.

[0010] Specifically, this structure allows the auxiliary furnace to continuously adjust the inner aperture without changing the overall structure, in order to adapt to the production needs of single crystal silicon pillars of different diameters, thereby improving the equipment's versatility and production flexibility.

[0011] In a preferred embodiment, the configuration is further as follows: several inner lining plates are spliced ​​together to form a ring structure, and an interlayer cavity is formed between the inner lining plates and the inner wall of the auxiliary furnace body. The interlayer cavity is continuously supplied with inert gas through an atmosphere injection port provided on the auxiliary furnace body and maintains a slightly positive pressure state.

[0012] Specifically, the sandwich cavity structure can effectively prevent corrosive gases from penetrating into the main metal load-bearing structure of the auxiliary furnace, thereby reducing the risk of corrosion of the main body of the auxiliary furnace in a high-temperature atmosphere.

[0013] In a preferred embodiment, the liner is further configured as follows: the inner liner is a double-layer composite structural component, with a dense anti-corrosion layer on the inner side and a buffer layer on the outer side, the buffer layer being used to absorb thermal stress and reduce crack formation; the inner liner is configured as a detachable installation structure by means of sliding pins and sliding strips.

[0014] Specifically, this structure allows the inner lining plates to be completely or partially disassembled and replaced when they reach the end of their service life or when they are partially damaged, thereby achieving continuous isolation and protection of the main body of the auxiliary furnace, extending the overall service life of the auxiliary furnace and reducing maintenance costs.

[0015] In a preferred embodiment, a sealing strip is provided at the sliding contact surface of adjacent inner lining plates, the sealing strip being made of a low-friction, high-temperature resistant, and corrosion-resistant material.

[0016] Specifically, the sealing strip ensures smooth relative sliding of the inner lining plates while sealing the joints between the inner lining plates, reducing the entry of corrosive gases into the interlayer cavity or the main body of the auxiliary furnace through the joints.

[0017] In a preferred embodiment, the liner is further configured such that: an air intake grille is provided on one side of the liner, and an air distribution strip is fixedly installed on the other side; an air guide channel connecting the air intake grille and the air distribution strip is provided inside the liner, and a number of tangentially arranged air grille holes are provided on the surface of the air distribution strip.

[0018] Specifically, after the inert gas is pressurized through the gas guide channel, it is ejected tangentially through the air grid holes, forming a continuous and stable air curtain layer on the surface of the inner lining plate. This forms an isolation barrier against corrosive gases, inhibiting their retention and deposition on the surface of the inner lining plate and in structural gaps.

[0019] In a preferred embodiment, the drive mechanism is further configured such that a sacrificial corrosion plate or a thin-walled calibration ring is provided on its top surface. Specifically, this structure facilitates the assessment of corrosion intensity inside the auxiliary furnace and the replacement cycle of the lining plates during equipment maintenance, thereby improving the predictability and safety of equipment operation and maintenance.

[0020] The beneficial effects achieved by this invention are as follows: 1. The drive mechanism in this invention can drive the rotary disk to rotate, and utilizes the oblique sliding guide between the rotary disk and the inner lining plate to cause several inner lining plates to synchronously deflect and radially slide during rotation, thereby achieving continuous adjustment of the aperture of the inner channel of the auxiliary furnace. This structure can flexibly adjust the inner hole size according to the pulling requirements of single crystal silicon pillars of different diameters without replacing the entire auxiliary furnace structure, significantly improving the applicability and production flexibility of the equipment.

[0021] 2. This invention employs a detachable inner lining plate as the main protective structure inside the auxiliary furnace, effectively isolating and protecting the main body of the auxiliary furnace in high-temperature and corrosive atmospheres. When the inner lining plate reaches the end of its service life or suffers localized wear, it can be completely or partially disassembled and replaced, preventing corrosion from directly affecting the metal load-bearing structure, thereby extending the overall service life of the auxiliary furnace and reducing maintenance costs.

[0022] 3. The present invention constructs a pressure equalization gas guiding channel inside the inner lining plate and forms a directional gas curtain structure in conjunction with the gas distribution strip, so that the inert gas forms a continuous and stable gas curtain isolation layer on the surface of the inner lining plate, effectively blocking the corrosion of the inner lining plate and the main body of the auxiliary furnace by corrosive gas, while reducing the retention and deposition of corrosive gas in the structural gaps, and further improving the corrosion resistance and operational stability of the auxiliary furnace in complex atmosphere environments. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of one embodiment of the present invention; Figure 2 This is a schematic cross-sectional view of the auxiliary furnace body according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the cross-sectional structure of the auxiliary furnace body according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the surface structure of the rotary disk according to an embodiment of the present invention; Figure 5 This is a schematic diagram of one end of the inner lining plate according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of the other end of the inner lining plate according to an embodiment of the present invention; Figure 7 This is an enlarged schematic diagram of a partial structure of the inner lining plate according to an embodiment of the present invention; Figure 8 This is a schematic diagram of the cross-sectional structure of the inner lining plate according to an embodiment of the present invention; Figure 9 This is a schematic diagram of the bearing ring surface structure according to an embodiment of the present invention.

[0024] Figure label: 100. Main body of auxiliary furnace; 110. Observation window; 120. Atmosphere inlet; 200. Worm gear actuator; 210. Rotary disc; 211. Guide groove; 300. Inner liner; 310. Sealing strip; 320. Air distribution strip; 301. Air intake grille; 302. Sliding pin; 303. Sliding strip; 321. Air grille hole; 400, bearing ring; 410, arc groove. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0026] It should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the invention.

[0027] The following describes, with reference to the accompanying drawings, some embodiments of the present invention, providing a corrosion-resistant Czochralski single crystal furnace auxiliary furnace.

[0028] Combination Figures 1-9 As shown, the present invention provides a corrosion-resistant Czochralski single crystal furnace auxiliary furnace, comprising an auxiliary furnace body 100, a worm gear drive 200, and several inner lining plates 300 arranged inside the auxiliary furnace body 100. The auxiliary furnace body 100 is installed at the top of the main furnace as the forming cavity structure of the Czochralski single crystal furnace. The crystal column is lifted upward along the axial direction within the channel formed by the several inner lining plates 300 and completes the drawing and forming process.

[0029] In this embodiment, the auxiliary furnace body 100 is a high-temperature resistant metal shell structure, and a bearing ring 400 is fixedly installed on its inner side. The bearing ring 400 has an annular structure and is coaxially arranged with the auxiliary furnace body 100, and is used to provide radial limiting and sliding support for the inner lining plate 300.

[0030] The bottom end of the auxiliary furnace body 100 is provided with a conical cap structure for communicating with the main furnace of the Czochralski single crystal furnace. The inner diameter of the top of the conical cap is the same as the inner diameter of the bearing ring 400 and they are arranged opposite to each other, so as to ensure that the crystal column keeps the axis aligned when passing through the connection part between the auxiliary furnace body 100 and the main furnace, and avoids swaying during the forming process.

[0031] In this embodiment, several inner lining plates 300 are arranged along the circumferential direction of the auxiliary furnace body 100, and adjacent inner lining plates 300 are spliced ​​together to form a forming channel inside the auxiliary furnace.

[0032] The inner liner 300 has a fan-shaped cross-section with smooth surfaces on both sides to reduce the sliding resistance between adjacent inner liner 300s; the width of the end connected to the air distribution strip 320 gradually decreases, which is conducive to forming a stable air curtain flow field.

[0033] An interlayer cavity structure is formed between the inner lining plate 300 and the auxiliary furnace body 100. Inert gas is continuously introduced into the interlayer cavity through the atmosphere injection port 120 provided on the inner side of the auxiliary furnace body 100 and a slightly positive pressure is maintained, making it difficult for corrosive gas to penetrate into the metal load-bearing structure of the auxiliary furnace body 100.

[0034] Structurally, the inner lining plate 300 is a double-layer composite component, with a dense anti-corrosion layer on the inner side and a buffer layer on the outer side to absorb thermal stress and reduce crack formation. The inner lining plate 300 forms a detachable installation structure through sliding pins 302 and sliding strips 303. When the inner lining plate 300 reaches the end of its service life or suffers local damage under long-term high temperature and corrosive atmosphere, it can be completely or partially disassembled and replaced, thereby providing continuous isolation and protection for the auxiliary furnace body 100.

[0035] In this embodiment, the worm gear drive 200 is installed on the upper part of the auxiliary furnace body 100, and its output end drives the rotary disk 210 to rotate around the axis. The bottom surface of the rotary disk 210 is provided with a plurality of radially inclined sliding guide grooves 211.

[0036] The top of the inner lining plate 300 is provided with a slide bar 303, which is slidably sleeved on the inner side of the guide groove 211; the bottom of the inner lining plate 300 is provided with a sliding pin 302, which is slidably sleeved on the inner side of the arc groove 410 on the surface of the bearing ring 400.

[0037] The arc-shaped slide groove 410 has different distances between its two ends and the center of the bearing ring 400. When the worm gear actuator 200 drives the rotary disk 210 to rotate, the geometric difference between the guide groove 211 and the arc-shaped slide groove 410 causes the inner liner plate 300 to deflect and slide radially synchronously during rotation, thereby changing the size of the inner channel aperture formed by the enclosed sections of the inner liner plates 300. By controlling the rotation angle of the worm gear actuator 200, the aperture of the auxiliary furnace can be continuously adjusted to meet the pulling requirements of single crystal silicon pillars of different diameters.

[0038] In this embodiment, a sealing strip 310 is provided at the sliding contact surface of adjacent inner lining plates 300. The sealing strip 310 is made of a low-friction, high-temperature resistant and corrosion-resistant material. While ensuring smooth relative sliding between the inner lining plates 300, it also seals the joint between the inner lining plates 300, thereby reducing the infiltration of corrosive gases into the interlayer cavity and the interior of the auxiliary furnace body 100.

[0039] In this embodiment, an atmosphere inlet 120 is provided on the inner surface of the auxiliary furnace body 100, and inert gas enters the interlayer cavity formed on the outer side of the inner lining plate 300 through the atmosphere inlet 120.

[0040] An air inlet grille 301 is provided on one side of the inner liner 300. The inert gas in the interlayer cavity enters the air guide channel 304 provided inside the inner liner 300 through the air inlet grille 301. After pressure equalization is completed in the air guide channel 304, it is discharged from the air distribution strip 320 fixedly installed on the other side of the inner liner 300.

[0041] The surface of the air distribution strip 320 has a plurality of air grid holes 321, which include air hole structures and strip hole structures. The ends of the air grid holes 321 face the surface of the adjacent inner liner plate 300 in the tangential direction, so that the sprayed inert gas forms a continuous and stable air curtain layer on the surface of the inner liner plate 300. This air curtain layer effectively isolates the corrosive gas, inhibits the intrusion of the corrosive gas into the surface of the inner liner plate 300 and the structural gaps, and reduces the retention and deposition of corrosive gas in local areas.

[0042] In this embodiment, the top surface of the worm gear drive 200 is provided with a sacrificial corrosion plate or a thin-walled calibration ring, which is used to visually judge the corrosion intensity inside the auxiliary furnace and the replacement cycle of the inner lining plate 300 during equipment maintenance, thereby improving the predictability and safety of equipment maintenance.

[0043] Working principle and usage process of this invention: In this invention, the auxiliary furnace body 100 is installed at the top of the main furnace of the Czochralski single crystal furnace and forms a forming cavity structure. During the pulling process, the single crystal silicon pillar is located within a channel formed by several inner lining plates 300, and is lifted vertically upward under the constraint and guidance of this channel to complete the forming. During use, the worm gear drive 200 drives the rotary disk 210 to rotate around its own axis. The inclined sliding guide groove 211 provided on the bottom surface of the rotary disk 210 forms a guiding engagement with the sliding strip 303 at the top of the inner lining plate 300. At the same time, the sliding pin 302 at the bottom end of the inner lining plate 300 forms a limiting engagement with the arc sliding groove 410 on the bearing ring 400.

[0044] When the rotary disk 210 rotates, due to the difference in radial position and center distance between the sliding guide groove 211 and the arc sliding groove 410, each inner liner plate 300 is simultaneously deflected and radially slid under the driving action of the rotary disk 210, causing the diameter of the inner channel formed by the enclosed space of several inner liner plates 300 to change. By controlling the rotation angle of the worm gear drive 200, the diameter of the inner hole of the auxiliary furnace body 100 can be continuously adjusted, thereby enabling the auxiliary furnace to adapt to the pulling requirements of single crystal silicon pillars of different diameters without replacing the overall auxiliary furnace structure or fixed inner liner components.

[0045] Regarding the protective structure of the auxiliary furnace, the inner lining plate 300 serves as the main isolation component inside the auxiliary furnace body 100, forming a sandwich cavity structure with the auxiliary furnace body 100. The inner lining plate 300 is detachably connected to the sliding pin 302 and the sliding strip 303. When the inner lining plate 300 experiences wear, corrosion, or reaches the end of its service life under long-term high temperature or corrosive atmosphere, it can be completely or partially disassembled and replaced without disassembling the auxiliary furnace body 100. This achieves continuous isolation and protection for the auxiliary furnace body 100, preventing corrosion from directly affecting the metal load-bearing structure of the auxiliary furnace body 100.

[0046] During the atmosphere protection and gas curtain isolation process, inert gas enters the interlayer cavity formed on the outer side of the liner plate 300 through the atmosphere inlet 120 on the auxiliary furnace body 100, and then enters the gas guiding channel 304 inside the liner plate 300 through the gas inlet grid 301 provided on one side of the liner plate 300. After pressure equalization is completed in the gas guiding channel 304, it is ejected tangentially through the gas grid holes 321 on the surface of the gas distribution strip 320 provided on the other side of the liner plate 300. The ejected inert gas forms a continuous and stable gas curtain layer on the surface of the liner plate 300. This gas curtain is distributed circumferentially along the liner plate 300, forming an isolation barrier against corrosive gases, inhibiting the intrusion of corrosive gases into the surface and structural gaps of the liner plate 300, and reducing the retention and deposition of corrosive gases in local areas.

[0047] Through the above working principle and usage process, this invention, while achieving adjustable inner hole diameter of the auxiliary furnace body 100, effectively improves the adaptability, corrosion resistance and long-term operational stability of the auxiliary furnace of the Czochralski single crystal furnace in complex high-temperature atmosphere environments by combining the structure of the detachable inner lining plate 300 with the atmosphere-gas curtain collaborative isolation mechanism.

[0048] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0049] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A corrosion-resistant auxiliary furnace for a Czochralski single crystal furnace, characterized in that, The system includes a secondary furnace body (100), a worm gear drive (200), and several inner lining plates (300) arranged inside the secondary furnace body (100). A bearing ring (400) is fixedly installed on the inner side of the secondary furnace body (100). Several arc grooves (410) are opened on the surface of the bearing ring (400), and a sliding pin (302) is provided at the bottom end of the inner lining plate (300) and is slidably sleeved inside the arc groove (410). The inner side of the worm gear drive (200) is rotatably mounted with a rotary disk (210) located inside the auxiliary furnace body (100). The bottom surface of the rotary disk (210) is provided with a plurality of sliding guide grooves (211). The top surface of the inner lining plate (300) is provided with a sliding strip (303) that is slidably sleeved inside the sliding guide grooves (211). A plurality of the inner lining plates (300) are combined to form an annular structure, and an interlayer cavity is formed between the outer periphery of the inner lining plate (300) and the inner wall of the auxiliary furnace body (100). Inert gas is continuously introduced into the interlayer cavity and a slight positive pressure is maintained to prevent corrosive gas from penetrating into the metal load-bearing layer of the auxiliary furnace body (100). One side of the inner lining plate (300) is provided with an air inlet grille (301), and the other side is fixedly installed with an air distribution strip (320). Several inner lining plates (300) are arranged along the circumference of the auxiliary furnace body (100), and adjacent inner lining plates (300) slide against each other. A sealing strip (310) is provided at the sliding contact surface of adjacent inner lining plates (300). The cross section of the inner lining plate (300) is fan-shaped, and the width of the end connected to the air distribution strip (320) gradually decreases. The opposite sides of the inner lining plate (300) are smooth and glossy. The worm gear drive (200) is used to drive the rotary disk (210) to rotate. The sliding guide groove (211) is arranged obliquely on the bottom surface of the rotary disk (210). The arc sliding groove (410) is arc-shaped, and its two ends are at different distances from the center of the bearing ring (400).

2. The corrosion-resistant auxiliary furnace for a Czochralski single crystal furnace according to claim 1, characterized in that, The gas distribution strip (320) has gas grid holes (321) on its surface, and the inner surface of the auxiliary furnace body (100) has an atmosphere inlet (120) that communicates with the gas inlet grid (301). The inner lining plate (300) has an internal gas guiding channel (304) for connecting the gas inlet grid (301) and the gas grid holes (321). After the gas in the interlayer cavity is evenly compressed by the gas inlet grid (301) and the internal gas guiding channel (304), it is distributed and blown out through the gas grid holes (321) on the surface of the gas distribution strip (320) to achieve circumferential uniform sweeping.

3. The corrosion-resistant auxiliary furnace for a Czochralski single crystal furnace according to claim 1, characterized in that, The bottom end of the auxiliary furnace body (100) is provided with a cone cap structure for communicating with the main furnace of the Czochralski single crystal furnace, and the inner diameter of the top of the cone cap is the same as the inner diameter of the bearing ring (400) and arranged opposite to each other.

4. The corrosion-resistant auxiliary furnace for a Czochralski single crystal furnace according to claim 1, characterized in that, The inner lining plate (300) is a double-layer composite structure component, including a dense anti-corrosion layer on the inner side and a buffer layer on the outer side. The dense anti-corrosion layer is used to block the penetration of corrosive gases, and the buffer layer is used to absorb thermal stress and reduce crack generation. The inner lining plate (300) is connected to the slide bar (303) by the sliding pin (302) to form a detachable installation structure.

5. A corrosion-resistant auxiliary furnace for a Czochralski single crystal furnace according to claim 1, characterized in that, The sealing strip (310) is a low-friction and corrosion-resistant component, and its material is selected from high-purity graphite, boron nitride, silicon carbide-based composite materials or their composite structures.

6. The corrosion-resistant auxiliary furnace for a Czochralski single crystal furnace according to claim 1, characterized in that, The air grid holes (321) on the surface of the air distribution strip (320) include a number of air hole structures and strip hole structures, and the ports of the air hole structures and strip hole structures are tangentially opposite to the surface of the adjacent inner liner plate (300), forming an circumferential air curtain on the surface of the inner liner plate (300).

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