Process tube and furnace tube equipment
By designing process tube areas with different wall thicknesses in the furnace tube equipment and combining them with heat dissipation devices, the problem of failure of the bottom seal of the process tube at high temperatures was solved, thus achieving stable operation of the equipment at high temperatures and improving the durability of the seal.
Patent Information
- Application Number
- CN202411003481.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-24
- Publication Date
- 2026-01-27
AI Technical Summary
The bottom seal of the process tube in traditional furnace tube equipment is prone to failure at high temperatures, and cannot meet the temperature requirements of more than 1200 degrees in semiconductor processes.
The process tube is designed to include a first region and a second region along the vertical direction. The second region is located outside the area surrounded by the heater and has a wall thickness smaller than that of the first region. Combined with a high-temperature resistant coating and a heat dissipation device, it improves heat dissipation efficiency and reduces temperature.
It improves the strength and heat dissipation capacity of the process pipes, avoids aging of seals and gaskets, and ensures stable operation of the equipment at high temperatures.
Smart Images
Figure CN121409008A_ABST
Abstract
Description
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 in this application is located outside the area surrounded by the heater. As a non-directly heated region, the second region receives less heat. The wall thickness of the second region is less than that of the first region. This reduced thickness improves the heat dissipation efficiency of the second region, allowing heat to dissipate more quickly. In summary, the process tube in the second region receives less heat and dissipates heat quickly, resulting in a lower temperature. The lower temperature of the process tube in the second region is due to its high strength and load-bearing capacity, preventing deformation. Furthermore, the process tube in the second region is less likely to cause aging and damage to components in contact with it, such as gaskets and seals. Attached Figure Description
[0009] Figure 1 This is a schematic diagram of the process tube structure of Embodiment 1 of this application;
[0010] Figure 2 For this application Figure 1 Enlarged view of point A in the middle;
[0011] Figure 3 This is a schematic diagram of the furnace tube equipment according to Embodiment 2 of this application;
[0012] Figure 4 For this application Figure 3 Enlarged view of point B in the middle;
[0013] Figure 5 This is a simulation cloud diagram of the first thermal field at the bottom of the furnace tube equipment in Embodiment 2 of this application;
[0014] Figure 6 This is a simulation cloud diagram of the second thermal field at the bottom of the furnace tube equipment in Embodiment 2 of this application.
[0015] Figure 7 This is a simulation cloud diagram of the third thermal field at the bottom of the furnace tube equipment in Embodiment 2 of this application. Detailed Implementation
[0016] The present application is further illustrated below by way of embodiments, but this does not limit the present application to the scope of the embodiments.
[0017] like Figure 1 and Figure 2 As shown, this embodiment provides a process tube 100 for use in a furnace tube device. The process tube 100 includes a first region 110 and a second region 120 in the vertical direction. The second region 120 is located below the first region 110 and is configured to be located outside the heater enclosure area of the furnace tube device. The wall thickness of the second region 120 is less than the wall thickness of the first region 110.
[0018] The second region 120 is located outside the area enclosed by the heater. As a non-directly heated region, the second region 120 receives less heat. The wall thickness of the second region 120 is less than that of the first region 110. This reduced thickness improves the heat dissipation efficiency of the second region 120, allowing heat to dissipate more quickly. The wall thickness of the first region 110 is greater than that of the second region 120. As a directly heated region, the first region 110 has a higher resistance to deformation at high temperatures, which improves its resistance to deformation. In summary, the first region 110 has improved resistance to deformation at high temperatures, and the second region 120 receives less heat and dissipates heat quickly, resulting in a lower temperature. The lower temperature of the second region 120 is beneficial because it has high strength and load-bearing capacity, preventing deformation. Furthermore, the second region 120 is less likely to cause components in contact with it to overheat and fail, such as gaskets and seals, leading to aging and damage.
[0019] The first region 110 may be wholly or partially located within the heater enclosure area of the furnace tube equipment, without limitation. The heater enclosure area refers to the area surrounded by the actual heating components in the heater; components such as the heater shell that do not have a heating function are not considered actual heating components.
[0020] 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 helps to further improve the high-temperature resistance of the process tube 100.
[0021] In some embodiments, a high-temperature resistant coating may be provided only on the outer wall of the first region 110.
[0022] In this 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 concave 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 thinning point of the second region 120 is located on the outer wall, and the inner walls of the first region 110 and the second region 120 are flush. The inner wall of the process tube 100 does not have steps, thus preventing product deposition at the transition between the first region 110 and the second region 120 during the reaction stage.
[0023] In other embodiments, the thickness reduction of the second region 120 may also be located on the inner wall, or the inner wall and the outer wall may be thinned simultaneously.
[0024] like Figure 2 As shown, in this embodiment, the transition between the pipe walls 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 pipe 100 includes an inner wall and an outer wall, and the thickness between the inner and outer walls is the wall thickness of the pipe.
[0025] In this embodiment, the process tube 100 is made of quartz.
[0026] In this embodiment, the wall thickness of the second region 120 is at least 1 / 4 of the wall thickness of the first region 110.
[0027] In this embodiment, the wall thickness of the first region 110 is greater than 7.5 mm. The first region 110 has a higher temperature; increasing the wall thickness helps resist deformation caused by high temperatures, making the first region 110 less prone to deformation and more stable. The selection of the wall thickness is related to the material of the process tube and the process temperature.
[0028] The advantages of the process tube 100 proposed in this application become more significant as the process temperature increases. The process tube is made of quartz material. When the process temperature reaches 1200℃ or higher, process tubes with conventional wall thicknesses may struggle to resist deformation caused by high temperatures. Increasing the wall thickness enhances the process tube's resistance to deformation at high temperatures, and without changing the material, the higher the process temperature, the greater the wall thickness. However, increasing the wall thickness reduces the heat dissipation capacity of the process tube, and poor heat dissipation in the lower region of the process tube can easily lead to failure of components in contact with it. Therefore, the process tube proposed in this application adopts a structure with a thicker upper section and a thinner lower section (i.e., the wall thickness of the second region is less than that of the first region), which can better balance the strength requirements of the first region and the heat dissipation requirements of the second region of the process tube at ultra-high temperature (e.g., above 1200℃) process temperatures.
[0029] Example 2
[0030] like Figure 3 As shown, this embodiment provides a furnace tube device, which includes a heater 300, an outer tube 200, and a process tube 100 as described above. The heater 300 surrounds the outer tube 200, and the outer tube 200 surrounds the first region 110 of the process tube 100. A second region 120 of the process tube 100 is located outside the region surrounded by the outer tube 200 and the heater 300. The location of the second region 120 outside the region surrounded by the outer tube 200 and the heater 300 provides installation space for the heat dissipation device 400 and minimizes heat exposure in the second region 120.
[0031] In this embodiment, the furnace tube equipment also includes a heat dissipation device 400, which surrounds the exterior of the second region 120. In this example, the heat dissipation device 400 includes a cavity 430 surrounding the outer wall of the second region 120. One end of the cavity 430 has an air inlet 410, and the other end has an air outlet 420, which is connected to the exhaust device of the furnace tube equipment. The heat dissipation device 400 uses air cooling; air enters through the air inlet 410 and exits through the air outlet 420, effectively carrying away a significant amount of heat. In some embodiments, the cooling method of the heat dissipation device 400 is not limited to this; water cooling can also be used. Compared to traditional process tubes with uniform wall thickness, in this application, the second region 120 has a thinner wall thickness than the first region 110, which improves the heat dissipation efficiency of the second region 120, lowering its temperature. Combined with the cooling effect of the heat dissipation device 400, the heat dissipated from the second region 120 can be carried away more quickly, further reducing the temperature of the second region 120. Its temperature distribution is as follows... Figure 5 As shown, the overall temperature below is lower than the overall temperature above (in a color image, different colors represent temperatures: blue for lower temperatures, green for medium temperatures, and red for higher temperatures). According to... Figure 5 The temperature at point C in the second region 120 of process tube 100 is about 91℃, and the temperature at point E, the transition point between the first region 110 and the second region 120, is about 500℃.
[0032] In this embodiment, as Figure 4 As shown, the furnace tube assembly also includes a flange 500 and a gasket 510. The bottom 121 of the second region 120 of the process tube 100 is connected to the flange 500, and the gasket 510 is disposed between the bottom 121 of the second region 120 of the process tube 100 and the flange 500. The flange 500 is connected to other components of the furnace tube assembly, such as the frame (not shown in the figure), thereby fixing the process tube 100. Since the flange 500 is made of metal, it cannot directly contact the quartz process tube 100. Therefore, a PTFE (polytetrafluoroethylene) gasket 510 is used here to prevent the flange 500 from damaging the process tube 100. (Refer to reference...) Figure 2 The bottom 121 of the second region 120 is an annular boss protruding radially outward along the process pipe. A flange 500 is fitted onto the upper and lower surfaces of the annular boss, and gaskets 510 are respectively provided between the upper and lower surfaces of the annular boss and the flange 500. In this embodiment, according to... Figure 5 The temperature at point D near gasket 510 is 34℃. Gasket 510 will not be affected by high temperature and will not age. Gasket 510 is more stable in use.
[0033] In this embodiment, the furnace tube equipment also includes a cover plate 600 and a seal 610. The cover plate 600 is connected to the lifting device of the crystal boat (not shown in the figure). The cover plate 600 can move vertically. When the cover plate 600 moves to the bottom of the second region 120, the cover plate 600 and the bottom of the second region 120 are sealed by the seal 610, thereby closing the process tube 100. The seal 610 is a sealing ring, located at the bottom of the second region 120, where its temperature is lower than that at point D. The seal 610 is also stable in use.
[0034] In some embodiments, the heat dissipation device 400 may not be provided.
[0035] Temperature distribution when the heat dissipation device 400 is not turned on is as follows Figure 6 As shown, the temperature at point C' in the second region 120 is about 205°C, and the temperature at point D' near the gasket 510 is 56°C. Although these temperatures are higher than the corresponding temperatures in the scheme where the heat dissipation device 400 is installed, they are still within the tolerance temperature range of the gasket 510 and the seal 610.
[0036] like Figure 5 and Figure 6 As shown, with the heat dissipation device 400 installed, the temperature at point C in the second region 120 is about 91°C. When the heat dissipation device 400 is not turned on, the temperature at point C' in the second region 120 is about 205°C. The positions of C and C' are basically the same, and the temperature drop is obvious, which shows that the heat dissipation effect of the second region 120 itself is good, and the heat dissipation device 400 can quickly reduce the temperature of the second region 120.
[0037] like Figure 6 and Figure 7 As shown, in Figure 6 The temperature at the transition point E' between the first region 110 and the second region 120 is approximately 500℃. Figure 7 The temperature at the transition point E” between the first region 110 and the second region 120 is also around 500℃, where E' and E” are both located outside the area enclosed by the heater. Figure 6 and Figure 7 The difference is: Figure 6 The length of the second region 120 in the middle is greater than Figure 7 The second region 120 is longer. Figure 6 The temperature at point C' is approximately 205℃, and the temperature at point D' is approximately 56℃. Figure 7The temperature at point C” in the second region is approximately 257℃, and the temperature at point D” is approximately 72℃. The positions of C’ and C” are essentially the same, as are the positions of D’ and D”. This shows that as the length of the second region 120 increases, the temperature at roughly the same locations decreases significantly. This indirectly indicates that the thinner design of the second region 120 has good heat dissipation and helps reduce the temperature.
[0038] While specific embodiments of this application have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of this application is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of this application, but all such changes and modifications fall within the scope of protection of this application.
Claims
1. A process tube for use in furnace tube equipment, characterized in that, The process tube includes a first region and a second region along the vertical direction. The second region is located below the first region and is configured to be located outside the heater enclosure area of the furnace tube equipment. The wall thickness of the second region is less than the wall thickness of the first region.
2. The process tube as described in claim 1, characterized in that, The outer wall of the first region is provided with a high-temperature resistant coating.
3. The process tube as described in claim 2, characterized in that, The material of the high-temperature resistant coating is any one or more of alumina, silicon carbide, or nanomaterials.
4. The process tube as described in claim 1, characterized in that, The inner walls of the first region and the second region are kept flush, and the outer wall of the second region is recessed inward relative to the 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 as described in claim 1, characterized in that, The process tube is made of quartz.
6. The process tube as described in claim 1, characterized in that, The wall thickness of the second region is at least 1 / 4 of the wall thickness of the first region.
7. The process tube as described in claim 1, 5, or 6, characterized in that, The wall thickness of the first region is greater than 7.5 mm.
8. The process tube as described in claim 1, characterized in that, The transition between the pipe walls in the first region and the second region is smooth.
9. A furnace tube device, characterized in that, It includes a heater, an outer tube, and a process tube as described in any one of claims 1-8, wherein the heater surrounds the outside of the outer tube, the outer tube surrounds the outside of the first region, and the second region is located outside the region surrounded by the outer tube and the heater.
10. The furnace tube equipment as described in claim 9, characterized in that, The furnace tube equipment also includes a heat dissipation device surrounding the exterior of the second region.
11. The furnace tube equipment as described in claim 9 or 10, characterized in that, The furnace tube equipment also includes a flange and a gasket, with the bottom of the second region connected to the flange, and the gasket disposed between the bottom of the second region and the flange.
12. The furnace tube equipment as described in claim 9 or 10, characterized in that, The furnace tube equipment also includes a cover plate and a sealing element. The cover plate is movable in a vertical direction. When the cover plate moves to the bottom of the second region, the cover plate and the bottom of the second region are sealed by the sealing element.