Sealing structure and sealing method for high-temperature furnace tube

Abstract

The present application provides a sealing structure and sealing method for a high-temperature furnace tube. The high-temperature furnace tube comprises a process tube and a base, the sealing structure of the high-temperature furnace tube comprises an annular rib provided on the top surface of the base, and the top surface of the annular rib is in contact with the bottom surface of the process tube and supports the process tube. The material of the annular rib is quartz, suitable for softening and deforming at a preset temperature to adhere to the bottom surface of the process tube. In the present application, due to the high-temperature softening characteristic of quartz, the internal temperature of the process tube is increased to reduce the strength of the quartz annular rib and cause minor deformation. The process tube adheres to the base under the action of gravity, achieving sealing between the process tube and the base.

Description

Sealing structure and sealing method of high-temperature furnace tube

[0001] This application claims priority to Chinese Patent Application No. 202410825152.9, filed on June 24, 2024, the contents of which are incorporated herein by reference in their entirety. TECHNICAL FIELD

[0002] The present application relates to the field of semiconductor manufacturing equipment, in particular to a sealing structure and sealing method of high-temperature furnace tube. BACKGROUND

[0003] High-temperature furnace tubes are mostly used in processes such as vapor deposition and oxidation annealing in semiconductor processes. Currently, the temperature of traditional semiconductor vapor deposition processes is between 800℃ and 1100℃. However, with the development of semiconductor power devices and more advanced semiconductor process devices, the process temperature requirement for high-temperature furnace tubes is getting higher and higher, and the traditional process temperature of 800℃ to 1100℃ has already been unable to meet the demand.

[0004] In semiconductor processes, in order to improve the diffusion speed of doped atoms in silicon wafers and to improve the deposition rate of oxide films, thereby improving the output of the equipment, the process temperature needs to reach about 1300℃, i.e., super-high-temperature process.

[0005] Generally, a high-temperature furnace tube includes a process tube made of silicon carbide material and a base made of quartz material, but it is difficult to ensure the sealing between the components of these two materials, which easily leads to the leakage of chemical gas inside the process tube. Moreover, since the silicon carbide material has good thermal conductivity, the temperature of the contact part between the process tube and the base quickly reaches 1000℃, so the conventional sealing ring sealing method cannot be used in super-high-temperature processes. SUMMARY

[0006] The present application aims to provide a sealing structure and sealing method of high-temperature furnace tube, which solves the problem that the process tube and the base cannot be sealed in super-high-temperature processes in the prior art.

[0007] To achieve the above object and other related objects, the present application provides a sealing structure of high-temperature furnace tube, which includes a process tube and a base, and the sealing structure includes an annular protruding rib arranged on the top surface of the base, the top surface of the annular protruding rib being in contact with and supporting the bottom surface of the process tube; the material of the annular protruding rib is quartz, which is suitable for being softened and deformed and then adhering to the bottom surface of the process tube at a preset temperature.

[0008] Further, the annular protruding rib is two, and a gap is left between the two annular protruding ribs to form an annular groove, which is used to form an annular channel with the bottom surface of the process tube after the annular protruding rib is softened and deformed.

[0009] Further, the bottom of the annular groove is further provided with an air inlet hole for providing the protective gas with a first temperature into the annular channel, the first temperature is less than the temperature at which the annular protrusions of the quartz material can be softened and deformed.

[0010] Further, the heights of the two annular protrusions are equal.

[0011] Further, the bottom areas of the two annular protrusions are greater than the top areas.

[0012] Further, the cross sections of the two annular protrusions in the longitudinal direction are trapezoidal.

[0013] Further, the annular groove further comprises a recess formed downwardly between the two annular protrusions.

[0014] Further, the cross section of the annular groove in the longitudinal direction is composed of two parts, the upper half is trapezoidal, and the lower half is rectangular or semicircular.

[0015] Further, the contact area S of the two annular protrusions and the bottom surface of the process tube is calculated according to the weight M of the process tube and the maximum yield strength σ of the quartz:

[0016] Wherein, g is the gravity coefficient, σ is the maximum yield strength of the quartz, and n is the safety factor.

[0017] Further, the bottom of the annular groove is further provided with an air outlet hole for discharging the gas in the annular groove.

[0018] Further, the base is further provided with an air inlet pipeline and an air outlet pipeline of the gas, one end of the air inlet pipeline and the air outlet pipeline is respectively connected with an air inlet and an air outlet, and the other end extends to the annular groove and intersects with the bottom of the annular groove to form the air inlet hole and the air outlet hole.

[0019] Further, a stopper is further provided between the air inlet hole and the air outlet hole for preventing the gas entering from the air inlet hole from directly flowing out from the air outlet hole; the top surface of the stopper is in contact with the bottom surface of the process tube, and the two ends of the stopper respectively extend to the two annular protrusions.

[0020] Further, the air inlet and the air outlet are further connected with a flow control device for detecting and controlling the flow of the gas.

[0021] Further, the air inlet and the air outlet are further provided with a valve for opening and closing the air inlet and the air outlet.

[0022] Further, the protective gas is nitrogen or noble gas.

[0023] Further, the ring-shaped ribs are three, and gaps are left between two adjacent ring-shaped ribs to form two ring-shaped grooves for forming two ring-shaped channels with the bottom surface of the process tube after the ring-shaped ribs are softened and deformed.

[0024] Further, a ring-shaped peripheral channel is further included around the outside of the base for passing protective gas after the ring-shaped ribs are softened and deformed.

[0025] The application further provides a sealing structure of a high-temperature furnace tube, which includes a base and a process tube arranged on the base, and the sealing structure includes ring-shaped ribs arranged on the top surface of the base, the top surface of the ring-shaped ribs being in contact with and supporting the bottom surface of the process tube; wherein the material of the ring-shaped ribs is quartz, and the ring-shaped ribs are softened and deformed to adhere to the bottom surface of the process tube.

[0026] The application further provides a high-temperature furnace tube including the above sealing structure.

[0027] The application further provides a sealing method of a high-temperature furnace tube, which uses the above sealing structure and includes the following steps:

[0028] arranging the process tube on the base;

[0029] increasing the temperature inside the process tube to a preset temperature, the preset temperature being the temperature at which the ring-shaped ribs of the quartz material can be softened and deformed;

[0030] after the ring-shaped ribs are softened and deformed to adhere to the bottom surface of the process tube, decreasing the temperature inside the process tube to a temperature lower than the preset temperature.

[0031] Further, the preset temperature ranges from 1350°C to 1400°C.

[0032] Further, when the ring-shaped ribs are multiple and a baffle is arranged between the gas inlet hole and the gas outlet hole at the bottom of the ring-shaped groove between two adjacent ring-shaped ribs, the method further includes: passing protective gas of a second temperature into the gap between the two adjacent ring-shaped ribs to obtain the ratio of the gas flow rates of the gas inlet hole and the gas outlet hole; determining whether the ratio is within a preset range, and if yes, considering that the ring-shaped ribs are softened and deformed and form ring-shaped channels with the bottom surface of the process tube; wherein the second temperature is greater than or equal to the temperature at which the ring-shaped ribs of the quartz material can be softened and deformed.

[0033] Further, the preset range of the ratio is 60% to 95%.

[0034] Further, when the sealing structure has the ring-shaped channels, the method further includes passing protective gas of a first temperature into the ring-shaped channels.

[0035] Further, when the sealing structure has two annular channels, the method further comprises introducing a protective gas of a first temperature into the annular channel of the inner ring, and pumping the annular channel of the outer ring.

[0036] Further, the method further comprises introducing a protective gas into the peripheral channel outside the base after the annular rib is softened and deformed.

[0037] Further, when the sealing structure has the annular channel, the air inlet hole and the air outlet hole at the bottom of the annular groove are provided with a block, the method further comprises: introducing a protective gas of a second temperature into the annular channel, obtaining the ratio of the gas flow of the air inlet hole and the air outlet hole, and determining whether the ratio is within a preset range, and if so, considering that the sealing performance of the sealing structure is good.

[0038] As described above, the present application provides a sealing structure and a sealing method of a high-temperature furnace tube, which has the following beneficial effects: a quartz annular rib is arranged on the base, and contacts and supports the bottom surface of the process tube, the internal temperature of the process tube is increased to reduce the strength of the quartz annular rib and cause a slight deformation, and the process tube is adhered to the base under the action of gravity, thereby realizing the sealing between the process tube and the base.

[0039] SUMMARY

[0040] The features and performances of the present application are further described by the following examples and drawings.

[0041] Fig. 1 shows a schematic diagram of a high-temperature furnace tube in an embodiment of the present application;

[0042] Fig. 2 shows a schematic diagram of a sealing structure of a high-temperature furnace tube in an embodiment of the present application;

[0043] Fig. 3 shows another schematic diagram of a sealing structure of a high-temperature furnace tube in an embodiment of the present application;

[0044] Fig. 4 shows a schematic diagram of a base in an embodiment of the present application;

[0045] Fig. 5 shows a top view of the base in an embodiment of the present application;

[0046] Fig. 6 shows a partial enlarged view of the circle-marked part of the base in Fig. 5;

[0047] Fig. 7 shows another schematic diagram of a sealing structure of a high-temperature furnace tube in an embodiment of the present application;

[0048] Fig. 8 shows a sectional view of the base in an embodiment of the present application.

[0049] Preferred embodiments of the present application

[0050] Following, the embodiments of the present application are described through specific examples, and other advantages and effects of the present application can be easily understood by those skilled in the art from the disclosure of the present specification. The present application can also be implemented or applied through other different embodiments, and various modifications or changes can be made to the details in the present specification based on different views and applications without departing from the spirit of the present application.

[0051] It should be noted that the diagrams provided in the embodiments only schematically illustrate the basic concepts of the present application, and although only the components related to the present application are shown in the diagrams, the actual implementation is not drawn according to the number, shape and size of the components, and the shape, number and proportion of the components in the actual implementation can be arbitrarily changed, and the layout form of the components can also be more complex. In addition, the parts represented by the same reference numerals in the multiple diagrams represent the same or equivalent parts or components.

[0052] The embodiments of the present application provide a sealing structure of a high-temperature furnace tube, as shown in FIG. 1, which includes a process tube 11 and an annular base 12. The material of the process tube 11 is silicon carbide, and the material of the base 12 is quartz. The part C circled in FIG. 1 is the sealing structure between the process tube 11 and the base 12. The sealing structure includes an annular rib provided on the top surface of the base 12, the top surface of the annular rib is in contact with the bottom surface of the process tube 11 and supports the process tube 11. The material of the annular rib is quartz, which is softened and deformed under high-temperature environment and adheres to the bottom of the process tube 11. Specifically, the temperature inside the process tube 11 is heated to a temperature at which the quartz is softened, for example, a temperature between 1350°C and 1400°C. The process tube 11 adheres to the base 12 under the action of gravity, which ensures good sealing effect of the process tube during the process.

[0053] In some embodiments, the number of annular ribs can be 2, including a first annular rib 121 and a second annular rib 122. Referring to FIG. 2, the first annular rib 121 and the second annular rib 122 are provided on the part of the top surface of the base 12 that is in contact with the process tube 11. The first annular rib 121 and the second annular rib 122 have the same height. The second annular rib 122 is provided outside the first annular rib 121. The process tube 11 is placed on the base 12 and is supported by the first annular rib 121 and the second annular rib 122 provided on the base 12. The materials of the first annular rib 121 and the second annular rib 122 are both quartz. The bottom area of the first annular rib 121 and the second annular rib 122 is greater than the top area. In some embodiments, the longitudinal cross-section of the first annular rib 121 and the second annular rib 122 is trapezoidal.

[0054] As shown in FIG. 2, to further ensure the sealing of the process tube, a gap is left between the first annular rib 121 and the second annular rib 122 to form an annular groove 123. When the quartz softens at high temperature, the annular groove 123 and the bottom surface of the process tube 11 form a sealed annular channel, which is used to fill the protective gas. The protective gas can be nitrogen or a noble gas. The temperature of the protective gas is lower than the temperature at which the annular rib of the quartz material can soften and deform, and is preferably at room temperature, such as about 25°C, to prevent the protective gas from being too hot to cause the annular rib to continue to soften and damage the stability of the sealing structure. In some embodiments, the annular groove 123 has a trapezoidal shape in the longitudinal cross-section.

[0055] Alternatively, the annular groove 123 can also include a recess formed downwardly between the first annular rib 121 and the second annular rib 122. As shown in FIG. 3, the annular groove 123 has a longitudinal cross-section composed of two parts, the upper half is the gap between the first annular rib 121 and the second annular rib 122, which can be trapezoidal, and the lower half is the aforementioned recess, which can be rectangular or semicircular. When the quartz softens at high temperature, the annular groove 123 can form a larger annular channel between the bottom surface of the process tube 11, which can fill more protective gas.

[0056] The contact area of the first annular rib 121 and the second annular rib 122 with the bottom surface of the process tube 11 is within a predetermined range, which is calculated according to the weight of the process tube 11 and the maximum yield strength of the quartz. Specifically, the range of the contact area S can be obtained according to the following formula:

[0057] where M is the weight of the process tube, g is the gravitational coefficient, σ is the maximum yield strength of the quartz, and n is the safety factor.

[0058] The width of the top circular ring of the first annular rib 121 and the second annular rib 122 can be obtained according to the contact area of the first annular rib 121 and the second annular rib 122 with the bottom surface of the process tube 11.

[0059] In other embodiments, only one annular rib can be provided without an annular channel. More than three annular ribs can also be provided, and an annular channel can be provided between any two adjacent annular ribs. Preferably, when there are three annular ribs, as shown in FIG. 7, a third annular rib 128 is further provided outside the second annular rib 122, and an outer annular groove 129 is formed between the two, which is connected to a gas extraction device. During the subsequent process, the outer annular groove 129 is subjected to gas extraction while the annular groove 123 is filled with protective gas, to prevent the leakage of chemical gas inside the process tube 11 and the protective gas to the outside of the furnace tube.

[0060] Referring to FIGS. 4-6, the base 12 is provided with a protective gas inlet pipe 124 and a protective gas outlet pipe 125 on the side. One end of the two pipes is respectively connected with a protective gas inlet 126 and a protective gas outlet 127, and the other end extends to the annular groove 123, and intersects with the bottom of the annular groove 123 to form an inlet hole 1231 and an outlet hole 1232. A stopper 1233 is arranged between the inlet hole 1231 and the outlet hole 1232 on the annular groove 123, which is used to prevent the protective gas entering from the inlet 126 from flowing out directly from the outlet 127, but flowing through the annular channel. The top surface of the stopper 1233 is in contact with the bottom surface of the process tube 11, and the stopper 1233 extends to the first annular rib 121 and the second annular rib 122 at both ends respectively. The material of the stopper 1233 is also quartz. Further, the height of the stopper 1233 is consistent with the height of the first annular rib 121 and the second annular rib 122.

[0061] The flow path of the gas in this application is: from the inlet 126 into the inlet pipe 124, through the inlet hole 1231 at the bottom of the annular groove to flow into the annular channel, then flow in the annular channel, and then through the outlet hole 1232 into the outlet pipe 125, and finally discharged from the outlet 127.

[0062] The flow control device (not shown in the figure) is also connected to the inlet 126 and the outlet 127, which is used to detect and control the flow of the gas, and then verify the softening degree of the quartz rib and the sealing effect through the gas flow of the outlet 127 and the inlet 126. Among them, the gas flow of the inlet 126 can be controlled at about 50 LPM (liter / minute) through the flow control device. Specifically, the verification method of the sealing effect is as follows: obtaining the ratio of the gas flow of the outlet 127 and the inlet 126, and judging whether the ratio is within the preset range, if so, it is considered that the sealing effect is good. In some embodiments, the preset range of the ratio is 60%-95%. In the subsequent process, the method can be continuously used to detect the sealing effect. After the protective gas is introduced, the outlet 127 and the inlet 126 are closed by closing the valves at the outlet 127 and the inlet 126, so that the protective gas in the annular channel is retained.

[0063] In other embodiments, the protective gas can also be introduced before the process starts, and the protective gas is continuously delivered during the process. When the protective gas is introduced, the valves at the outlet 127 and the inlet 126 can be opened to allow the protective gas to be discharged, so as to prevent the gas from impacting and damaging the softened annular rib in the annular channel.

[0064] The bottom of the base 12 is also provided with a metal plate, and a sealing ring is arranged between the two, for sealing the process cavity. When the temperature inside the process tube 11 rises, heat is easily transferred to the bottom of the base 12, causing the sealing ring to melt. As shown in FIG. 8, a ring-shaped peripheral channel 120 is further arranged around the outer side of the base 12, which is used to pass protective gas after the ring-shaped rib is softened and deformed, and in subsequent processes, to prevent heat in the process tube 11 from being transferred to the bottom of the base 12, and to prevent the sealing ring between the bottom of the base 12 and the metal plate from melting. The temperature of the protective gas is usually room temperature, such as about 25°C. As shown in FIG. 6, the peripheral channel 120 is connected with a gas inlet 1201 and a gas outlet 1202, for the inlet and outlet of the protective gas.

[0065] The application also provides a sealing method for a high-temperature furnace tube, which uses the sealing structure in the above embodiments, and the sealing method comprises the following steps:

[0066] The process tube is arranged on the base. The structure of the two is shown in FIG. 1, at this time the top surface of the ring-shaped rib is in contact with and supports the bottom surface of the process tube.

[0067] The temperature inside the process tube is raised to a preset temperature, which is the temperature at which quartz can be softened and deformed. In this process, the ring-shaped rib is softened and deformed, and adheres to the bottom surface of the process tube which is kept pressed down under the action of gravity.

[0068] After the ring-shaped rib is softened and deformed and adheres to the bottom surface of the process tube, the temperature inside the process tube is lowered to below the preset temperature.

[0069] In some embodiments, the preset temperature can be in the range of 1350°C to 1400°C.

[0070] After the ring-shaped rib is softened and deformed and adheres to the bottom surface of the process tube, the temperature inside the process tube is lowered to below the preset temperature. This prevents the ring-shaped rib from continuing to soften, and destroys the stability of the sealing structure.

[0071] In the example in which the sealing structure has a ring-shaped channel, the ring-shaped rib and the bottom surface of the process tube form a sealed ring-shaped channel after adhesion. This method further passes protective gas into the ring-shaped channel formed between the ring-shaped groove and the bottom surface of the process tube, further isolating the chemical gas inside the process tube from the outside air, to achieve a sealing effect.

[0072] In some embodiments, the method further comprises, after the ring-shaped rib is softened and deformed, passing protective gas at room temperature into the peripheral channel on the outer side of the base, to prevent heat in the process tube from being transferred to the bottom of the base.

[0073] In the example with multiple annular ribs, the method further comprises: introducing a protective gas at a second temperature into the gap between two adjacent annular ribs, obtaining the ratio of the gas flow rates at the inlet and outlet, and determining whether the ratio is within a preset range. If yes, it is considered that the annular rib is softened and deformed, and forms an annular channel with the bottom surface of the process tube. The preset range of the ratio is 60% to 95%. The second temperature is greater than or equal to the temperature at which the annular rib of the quartz material can be softened and deformed, and is preferably 1500°C. The sealing effect can be continuously detected by using the method in the subsequent process.

[0074] In the example with two annular channels in the sealing structure, the method further comprises: introducing a protective gas at a first temperature into the inner annular channel, and performing gas extraction on the outer annular channel.

[0075] In some embodiments, the method further comprises, after the annular rib is softened and deformed to adhere to the bottom surface of the process tube, introducing a protective gas into the peripheral channel outside the base. The temperature of the protective gas can be room temperature, such as about 25°C.

[0076] The sealing method is applied to the installation stage of the high-temperature furnace tube. After the quartz rib is softened and deformed, the process tube adheres to the base under the action of gravity, and a sealed annular channel is formed between the annular groove and the bottom surface of the process tube. Introducing a protective gas into the annular channel can isolate the chemical gas inside the process tube from the external air. In the process, the process tube does not need to be heated to soften the quartz rib, and the process can be directly performed. Moreover, the super-high-temperature process temperature is generally 1300°C, which is lower than the temperature at which the quartz is softened and deformed, so the stability of the structure and the good sealing effect can be maintained.

[0077] The above embodiments are only illustrative of the principles and effects of the present application, and are not intended to limit the present application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical idea disclosed in the present application should be covered by the claims of the present application.

Claims

1. A sealing structure for a high-temperature furnace tube, the high-temperature furnace tube comprising a base and a process tube adapted to be disposed on the base, characterized in that, The sealing structure includes an annular rib on the top surface of the base. The top surface of the annular rib contacts the bottom surface of the process tube and supports the process tube. The material of the annular rib is quartz, which is suitable for softening and deforming at a preset temperature and then adhering to the bottom surface of the process tube.

2. The sealing structure of the high-temperature furnace tube according to claim 1, characterized in that, There are two annular ribs, and a gap is left between the two annular ribs to form an annular groove, which is used to form an annular channel with the bottom surface of the process tube after the annular ribs are softened and deformed.

3. The sealing structure of the high-temperature furnace tube according to claim 2, characterized in that, The bottom of the annular groove is also provided with an air inlet for providing protective gas at a first temperature to the annular channel. The first temperature is lower than the temperature at which the annular ribs of the quartz material can soften and deform.

4. The sealing structure of the high-temperature furnace tube according to claim 2, characterized in that, The two annular ribs are of equal height.

5. The sealing structure of the high-temperature furnace tube according to claim 2, characterized in that, The bottom area of ​​both annular ribs is greater than the top area.

6. The sealing structure of the high-temperature furnace tube according to claim 5, characterized in that, Both annular ribs have trapezoidal cross-sections in the longitudinal direction.

7. The sealing structure of the high-temperature furnace tube according to claim 5, characterized in that, The annular groove also includes a depression formed downward from the middle of the two annular ribs.

8. The sealing structure of the high-temperature furnace tube according to claim 7, characterized in that, The annular groove has a longitudinal cross-section consisting of two parts: the upper part is trapezoidal and the lower part is rectangular or semi-circular.

9. The sealing structure of the high-temperature furnace tube according to claim 2, characterized in that, The contact area S between the two annular ribs and the bottom surface of the process tube is calculated based on the weight M of the process tube and the maximum yield strength σ of the quartz: Where g is the gravity coefficient, σ is the maximum yield strength of quartz, and n is the safety factor.

10. The sealing structure of the high-temperature furnace tube according to claim 3, characterized in that, The bottom of the annular groove is also provided with an air outlet for discharging the gas inside the annular groove.

11. The sealing structure of the high-temperature furnace tube according to claim 10, characterized in that, The base is also provided with a gas inlet pipe and a gas outlet pipe. One end of the gas inlet pipe and the gas outlet pipe are respectively connected to an air inlet and an air outlet, and the other end extends to the annular groove and intersects with the bottom of the annular groove to form the air inlet hole and the air outlet hole.

12. The sealing structure of the high-temperature furnace tube according to claim 11, characterized in that, A baffle is provided between the air inlet and the air outlet to prevent gas entering from the air inlet from flowing directly out of the air outlet; the top surface of the baffle contacts the bottom surface of the process tube, and both ends of the baffle extend to the two annular ribs respectively.

13. The sealing structure of the high-temperature furnace tube according to claim 11, characterized in that, The air inlet and outlet are also connected to a flow control device for detecting and controlling the gas flow rate.

14. The sealing structure of the high-temperature furnace tube according to claim 11, characterized in that, The air inlet and outlet are also equipped with valves for opening and closing the air inlet and outlet.

15. The sealing structure of the high-temperature furnace tube according to claim 3, characterized in that, The protective gas is nitrogen or a rare gas.

16. The sealing structure of the high-temperature furnace tube according to claim 1, characterized in that, There are three annular ribs, with gaps between adjacent annular ribs to form two annular grooves. These grooves are used to form two annular channels with the bottom surface of the process tube after the annular ribs have softened and deformed. The inner annular channel is used to introduce protective gas, and the outer annular channel is used to extract gas.

17. The sealing structure of the high-temperature furnace tube according to claim 1, characterized in that, It also includes a ring-shaped peripheral channel around the outside of the base, used to introduce protective gas after the ring-shaped rib has softened and deformed.

18. A sealing structure for a high-temperature furnace tube, the high-temperature furnace tube comprising a base and a process tube disposed on the base, characterized in that, The sealing structure includes an annular rib on the top surface of the base, the top surface of the annular rib contacting and supporting the bottom surface of the process tube; wherein the material of the annular rib is quartz, and the annular rib is softened and deformed to adhere to the bottom surface of the process tube.

19. A high-temperature furnace tube, comprising the sealing structure as described in any one of claims 1-18.

20. A sealing method for a high-temperature furnace tube, employing the sealing structure as described in any one of claims 1 to 17, characterized in that, Includes the following steps: The process tube is mounted on the base; The internal temperature of the process tube is raised to a preset temperature, which is the temperature at which the annular ribs of the quartz material can soften and deform. After the annular rib is softened and deformed and adheres to the bottom surface of the process tube, the internal temperature of the process tube is reduced to below a preset temperature.

21. The sealing method for high-temperature furnace tubes according to claim 20, characterized in that, The preset temperature range is 1350℃~1400℃.

22. The sealing method for high-temperature furnace tubes according to claim 20, characterized in that, When there are multiple annular ribs, and a baffle is provided between the air inlet and air outlet at the bottom of the annular groove between adjacent annular ribs, the method further includes: introducing a protective gas at a second temperature into the gap between two adjacent annular ribs, obtaining the ratio of the gas flow rate at the air inlet and the air outlet; determining whether the ratio is within a preset range, and if so, considering that the annular rib has softened and deformed, and forms an annular channel with the bottom surface of the process tube; wherein, the second temperature is greater than or equal to the temperature at which the annular rib of quartz material can soften and deform.

23. The sealing method for high-temperature furnace tubes according to claim 22, characterized in that, The preset range for the ratio is 60% to 95%.

24. The sealing method for high-temperature furnace tubes according to claim 20, characterized in that, When the sealing structure has the annular channel, the method further includes introducing a protective gas at a first temperature into the annular channel.

25. The sealing method for high-temperature furnace tubes according to claim 20, characterized in that, When the sealing structure has two annular channels, the method further includes introducing a protective gas at a first temperature into the inner annular channel and evacuating the outer annular channel.

26. The sealing method for high-temperature furnace tubes according to claim 20, characterized in that, The method further includes introducing protective gas into the peripheral channel outside the base after the annular rib has softened and deformed.

27. The sealing method for high-temperature furnace tubes according to claim 20, characterized in that, When the sealing structure has the annular channel and a baffle is provided between the air inlet and the air outlet at the bottom of the annular groove, the method further includes: introducing a protective gas at a second temperature into the annular channel, obtaining the ratio of the gas flow rate at the air inlet and the air outlet, determining whether the ratio is within a preset range, and if so, considering the sealing structure to have good sealing performance.

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