Process tube and furnace tube apparatus

Abstract

The present application relates to the field of semiconductor manufacturing apparatuses. Disclosed are a process tube and a furnace tube apparatus. The process tube is used in the furnace tube apparatus. The process tube comprises a first region and a second region in a vertical direction, wherein the second region is located below the first region, the second region is configured to be located outside an area surrounded by a heater of the furnace tube apparatus, and the wall thickness of the second region is less than that of the first region. The process tube in the second region receives less heat and dissipates heat quickly, such that the temperature of the process tube in the second region is relatively low. Since the temperature of the process tube in the second region is relatively low, the process tube in the second region is strong and has a strong bearing capacity, and does not deform itself, and also, the process tube in the second region is less likely to cause aging and damage to components in contact therewith, such as gaskets and seals.

Description

Process tubes and furnace tube equipment Technical Field

[0001] This application relates to the field of semiconductor manufacturing equipment, specifically to a process tube and furnace tube device. Background Technology

[0002] Furnace tube equipment is currently the main equipment for semiconductor diffusion, oxidation, annealing and other processes. The accuracy and uniformity of its reaction gas flow control are key performance indicators of the equipment.

[0003] In furnace tube equipment, the traditional semiconductor vapor deposition process temperature is 800-1100 degrees Celsius. However, with the development of semiconductor power devices and more advanced semiconductor process technologies, the process temperature requirements for furnace tubes are becoming increasingly higher, and the traditional process temperature cannot meet the requirements.

[0004] In semiconductor manufacturing, to increase the diffusion rate of doped atoms in silicon wafers, improve the deposition rate of oxide films, and increase equipment output, process temperatures exceeding 1200 degrees Celsius are required. As the process temperature increases, the temperature of the process transistor also rises. To ensure sealing, a seal is installed at the bottom of the process transistor. However, when the bottom temperature of the process transistor becomes too high, this seal is prone to failure. Summary of the Invention

[0005] This application addresses the technical problem of easy failure of the bottom seal of the process pipe through the following technical solution:

[0006] A process tube for use in a furnace tube apparatus, the process tube comprising a first region and a second region in a vertical direction, the second region being located below the first region and configured to be located outside the heater enclosure region of the furnace tube apparatus, the wall thickness of the second region being less than the wall thickness of the first region.

[0007] A furnace tube apparatus includes a heater, an outer tube, and a process tube as described above, wherein the heater surrounds the outside of the outer tube, the outer tube surrounds the outside of a first region, and a second region is located outside the region surrounded by the outer tube and the heater.

[0008] The second region of the process tube of the present application is located outside the surrounding area of the heater, and the second region serves as a non-directly-heated region, and the second region is heated less. The wall thickness of the second region is less than the wall thickness of the first region, and the thickness is reduced, which is beneficial to improve the heat dissipation efficiency of the second region, and the heat of the second region can be dissipated faster. In summary, the process tube of the second region is heated less, and the heat dissipation is fast, so that the temperature of the process tube of the second region is lower. The temperature of the process tube of the second region is lower, on the one hand, its strength is high, and the carrying capacity is strong, and it will not deform itself; on the other hand, the process tube of the second region is not easy to cause the aging damage of the components in contact with it, such as gaskets and sealing elements.

[0009] SUMMARY

[0010] The features and performances of the present application are further described by the following examples and their accompanying drawings.

[0011] Fig. 1 is a structural schematic view of a process tube according to an embodiment of the present application;

[0012] Fig. 2 is an enlarged view of A in Fig. 1 according to an embodiment of the present application;

[0013] Fig. 3 is a structural schematic view of a furnace tube device according to an embodiment of the present application;

[0014] Fig. 4 is an enlarged view of B in Fig. 3 according to an embodiment of the present application;

[0015] Fig. 5 is a first thermal field simulation cloud diagram of the lower part of the furnace tube device according to an embodiment of the present application;

[0016] Fig. 6 is a second thermal field simulation cloud diagram of the lower part of the furnace tube device according to an embodiment of the present application;

[0017] Fig. 7 is a third thermal field simulation cloud diagram of the lower part of the furnace tube device according to an embodiment of the present application.

[0018] Preferred embodiments of the present application

[0019] The present application will be further described below by way of examples, but the present application is not limited in the scope of the examples.

[0020] As shown in Figs. 1 and 2, the present embodiment provides a process tube 100 for use in a furnace tube device, the process tube 100 comprises a first region 110 and a second region 120 in the vertical direction, the second region 120 is located below the first region 110, the second region 120 is configured to be located outside the heater surrounding area of the furnace tube device, and the wall thickness of the second region 120 is less than the wall thickness of the first region 110.

[0021] The second region 120 is located outside the heater surrounding region, and the second region 120 is a non-directly heated region, and the second region 120 is heated less. The wall thickness of the second region 120 is less than the wall thickness of the first region 110. The thickness reduction is beneficial to improve the heat dissipation efficiency of the second region 120, so that the heat of the second region 120 can be dissipated faster. The wall thickness of the first region 110 is greater than the wall thickness of the second region 120, and the first region 110 is a directly heated region, which is beneficial to improve the deformation resistance of the first region 110 at high temperature. In summary, the deformation resistance of the first region 110 at high temperature is improved, the second region 120 is heated less and dissipates heat faster, so that the temperature of the second region 120 is lower. The temperature of the second region 120 is lower, on the one hand, its strength is high, and its bearing capacity is strong, and it will not deform itself; on the other hand, the second region 120 is not easy to make the temperature of the components in contact with it too high and fail, such as the aging and damage of the gasket and the sealing element.

[0022] The first region 110 can be located entirely or partially in the heater surrounding region of the furnace tube device, which is not limited herein. The heater surrounding region refers to the region surrounded by the actual heating components in the heater, and the components without heating function such as the shell of the heater do not belong to the actual heating components.

[0023] The outer wall of the process tube 100 is provided with a high-temperature-resistant coating. Specifically, the material of the high-temperature-resistant coating is any one or more of alumina, silicon carbide or nanomaterials, which is beneficial to further improve the high-temperature-resistant capability of the process tube 100.

[0024] In some embodiments, the high-temperature-resistant coating can also be provided only on the outer wall of the first region 110.

[0025] In the present embodiment, the inner walls of the first region 110 and the second region 120 are flush, and the outer wall of the second region 120 is recessed inward relative to the outer wall of the first region 110, so that the wall thickness of the second region 120 is less than the wall thickness of the first region 110. The thickness reduction of the second region 120 is located at the outer wall, and the inner walls of the first region 110 and the second region 120 are flush, and there is no step in the inner wall of the process tube 100, so that the deposition of the product is not generated at the transition of the first region 110 and the second region 120 during the reaction stage.

[0026] In other embodiments, the thickness reduction of the second region 120 can also be located at the inner wall, or the inner wall and the outer wall are simultaneously reduced.

[0027] As shown in FIG. 2, in the present embodiment, the transition of the pipe wall of the first region 110 and the second region 120 is smooth, avoiding stress concentration. It should be noted that the pipe wall of the process tube 100 includes the inner wall and the outer wall, and the thickness between the inner wall and the outer wall is the wall thickness of the pipe wall.

[0028] In the embodiment, the material of the process tube 100 is quartz.

[0029] In the embodiment, the wall thickness of the second region 120 is at least 1 / 4 of the wall thickness of the first region 110.

[0030] In the embodiment, the wall thickness of the first region 110 is greater than 7.5 mm. The temperature of the first region 110 is high, and increasing the wall thickness can resist the deformation caused by high temperature, so that the first region 110 is not easy to deform and is more stable. The selection of the wall thickness is related to the material of the process tube and the process temperature.

[0031] The advantages of the process tube 100 proposed in the application will become more significant as the process temperature increases. The process tube is made of quartz material, and when the process temperature reaches 1200℃ or above, the process tube with a conventional wall thickness may be difficult to resist the deformation caused by high temperature. Increasing the wall thickness of the process tube can enhance the anti-deformation ability of the process tube at high temperature, and without changing the material of the process tube, the higher the process temperature, the greater the wall thickness of the process tube. However, the increase of the wall thickness will reduce the heat dissipation capacity of the process tube, and the poor heat dissipation of the lower region of the process tube will easily lead to the failure of the components in contact with it. Therefore, the wall of the process tube proposed in the application adopts the structure of thick upper and thin lower (i.e. the wall thickness of the second region is less than the wall thickness of the first region), which can better balance the strength requirement of the first region of the process tube and the heat dissipation requirement of the second region of the process tube at an ultra-high temperature (for example, greater than 1200℃).

[0032] Embodiment 2

[0033] As shown in FIG. 3, the embodiment provides a furnace tube device, which comprises a heater 300, an outer tube 200 and the process tube 100 as above, the heater 300 is surrounded outside the outer tube 200, the outer tube 200 is surrounded outside the first region 110 of the process tube 100, and the second region 120 of the process tube 100 is located outside the surrounding area of the outer tube 200 and the heater 300. The second region 120 is located outside the surrounding area of the outer tube 200 and the heater 300, which can provide installation space for the heat dissipation device 400 on the one hand, and the second region 120 is less heated on the other hand.

[0034] In this embodiment, the furnace tube device further comprises a heat dissipation device 400, which surrounds the outside of the second region 120. In this example, the heat dissipation device 400 comprises a cavity 430 surrounding the outer wall of the second region 120, one end of the cavity 430 is provided with an air inlet 410, and the other end is provided with an air outlet 420, which is connected with the exhaust device of the furnace tube device. The heat dissipation device 400 adopts air cooling mode, air enters from the air inlet 410 and exhausts from the air outlet 420, which can carry away a large amount of heat. In some embodiments, the cooling mode of the heat dissipation device 400 is not limited to this, and water cooling mode can also be used for cooling. Compared with the traditional process tube with uniform wall thickness, in this application, the wall thickness of the second region 120 is thinned relative to the first region 110, which is beneficial to improve the heat dissipation efficiency of the second region 120, so that the temperature of the second region 120 is reduced, and the heat dissipation device 400 is used for cooling, which can more quickly carry away the heat emitted by the second region 120, and is beneficial to further reduce the temperature of the second region 120. The temperature distribution is shown in Figure 5, the overall temperature of the lower part is lower than that of the upper part, (when it is a color picture, different colors are used to represent the temperature, lower temperature corresponds to blue, medium temperature corresponds to green, and higher temperature corresponds to red). According to Figure 5, the temperature at C in the second region 120 of the process tube 100 is about 91°C, and the temperature at E in the transition between the first region 110 and the second region 120 is about 500°C.

[0035] In this embodiment, as shown in Figure 4, the furnace tube device further comprises a flange 500 and a gasket 510, the bottom 121 of the second region 120 of the process tube 100 is connected with the flange 500, and the gasket 510 is arranged between the bottom 121 of the second region 120 of the process tube 100 and the flange 500. The flange 500 is connected with other parts of the furnace tube device, such as the frame (not shown in the figure), so as to fix the process tube 100. Since the flange 500 is made of metal material and cannot be directly in contact with the process tube 100 made of quartz material, the gasket 510 made of PTFE (polytetrafluoroethylene) material is used here to avoid damage to the process tube 100 caused by the flange 500. In combination with reference to Figure 2, the bottom 121 of the second region 120 is an annular boss protruding outward along the radial direction of the process tube, the flange 500 is assembled on the upper surface and the lower surface of the annular boss, and the gasket 510 is arranged between the upper surface and the lower surface of the annular boss and the flange 500. In this embodiment, according to Figure 5, the temperature at D near the gasket 510 is 34°C, the gasket 510 will not be affected by high temperature and will not be aged, and the use of the gasket 510 is more stable.

[0036] In the embodiment, the furnace tube device further comprises a cover plate 600 and a sealing member 610, the cover plate 600 is connected with a lifting device (not shown in the figure) of the wafer boat, the cover plate 600 can move in the vertical direction, when the cover plate 600 moves to the bottom of the second area 120, the cover plate 600 is sealed with the bottom of the second area 120 through the sealing member 610, so as to enclose the process tube 100. The sealing member 610 adopts a sealing ring, and the sealing member 610 is located at the bottom end of the second area 120, and the temperature of the sealing member 610 is lower than the temperature at the position D. The use of the sealing member 610 is also stable.

[0037] In some embodiments, the heat dissipation device 400 can also not be provided.

[0038] The temperature distribution when the heat dissipation device 400 is not turned on is shown in FIG. 6, the temperature at C' in the second area 120 is about 205℃, and the temperature at D' close to the gasket 510 is about 56℃, which is higher than the temperature at the corresponding position in the scheme of providing the heat dissipation device 400, but is within the temperature tolerance of the gasket 510 and the sealing member 610.

[0039] As shown in FIGS. 5 and 6, the temperature at C in the second area 120 is about 91℃ when the heat dissipation device 400 is provided, and the temperature at C' in the second area 120 is about 205℃ when the heat dissipation device 400 is not turned on, wherein the positions of C and C' are basically the same, and the temperature decreases obviously, which can indicate that the heat dissipation effect of the second area 120 itself is good, and the heat dissipation device 400 can quickly reduce the temperature of the second area 120.

[0040] As shown in FIGS. 6 and 7, the temperature at E' in the transition between the first area 110 and the second area 120 in FIG. 6 is about 500℃, and the temperature at E" in the transition between the first area 110 and the second area 120 in FIG. 7 is also about 500℃, wherein the positions of E' and E" are both located outside the surrounding area of the heater. The difference between FIGS. 6 and 7 is that the length of the second area 120 in FIG. 6 is longer than the length of the second area 120 in FIG. 7. The temperature at C' in FIG. 6 is about 205℃, and the temperature at D' is about 56℃; the temperature at C" in FIG. 7 is about 257℃, and the temperature at D" is about 72℃, wherein the positions of C' and C" are basically the same, and the positions of D' and D" are basically the same. It can be seen that when the length of the second area 120 increases, the temperature at the approximately same position decreases obviously, which can indirectly indicate that the heat dissipation effect of the thinning design of the second area 120 is good, and is beneficial to reduce the temperature.

[0041] Although the specific embodiments of the application are described above, it should be understood that the scope of protection of the present application is not limited to the specific embodiments described above. Those skilled in the art can make various changes or modifications to the embodiments without departing from the principles and spirit of the present application, and such changes and modifications are also within the scope of protection of the present application.

Claims

1. A process tube for use in a tube furnace apparatus, characterized by, The process tube comprises a first region and a second region in a vertical direction, the second region is below the first region, the second region is configured to be outside a heater surrounding region of the furnace tube device, and a wall thickness of the second region is less than a wall thickness of the first region.

2. The process tube of claim 1, wherein, An outer wall of the first region is provided with a high-temperature-resistant coating.

3. The process tube of claim 2, wherein, The high-temperature-resistant coating is made of any one or more of alumina, silicon carbide or nanomaterials.

4. The process tube of claim 1, wherein, Inner walls of the first region and the second region are kept flush, and an outer wall of the second region is concave inward relative to an outer wall of the first region, so that the wall thickness of the second region is less than the wall thickness of the first region.

5. The process tube of claim 1, wherein, The process tube is made of quartz.

6. The process tube of claim 1, wherein, The wall thickness of the second region is at least 1 / 4 of the wall thickness of the first region.

7. The process tube of claim 1 or 5 or 6, wherein, The wall thickness of the first region is greater than 7.5 mm.

8. The process tube of claim 1, wherein, The pipe wall of the first region and the second region is smooth.

9. A furnace tube apparatus, characterized by, The furnace tube device comprises a heater, an outer tube and a process tube as claimed in any one of claims 1-8, the heater is surrounded outside the outer tube, the outer tube is surrounded outside the first region, and the second region is outside the surrounding region of the outer tube and the heater.

10. The furnace tube apparatus of claim 9, wherein, The furnace tube device further comprises a heat dissipation device, which is surrounded outside the second region.

11. The furnace tube apparatus of claim 9 or 10, wherein, The furnace tube device further comprises a flange and a gasket, the bottom of the second region is connected with the flange, and the gasket is arranged between the bottom of the second region and the flange.

12. The furnace tube apparatus of claim 9 or 10, wherein, The furnace tube device further comprises a cover plate and a sealing element, the cover plate is movable in a vertical direction, and the cover plate is sealed with the bottom of the second region through the sealing element when the cover plate moves to the bottom of the second region.

Images