Gas inlet duct for a furnace tube and furnace tube
By installing an outlet position adjustment device on the furnace tube inlet pipe, the gas outlet position is adjusted to be closer to the exhaust port, which solves the problem of poor uniformity within the wafer in the heat treatment process, and achieves the effect of improving wafer uniformity and increasing product yield.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHANGHAI INTEGRATED CIRCUIT EQUIPMENT & MATERIALS INDUSTRY INNOVATION CENTER CO LTD
- Filing Date
- 2023-07-11
- Publication Date
- 2026-06-12
AI Technical Summary
In the heat treatment process, the gas flows along a parabolic path on the wafer surface to the exhaust port of the furnace tube, resulting in poor uniformity within the wafer, causing differences in film thickness and standard deviation, which affects product yield.
An outlet position adjustment device is installed on the gas inlet pipe of the furnace tube. The gas outlet position is adjusted by designing the gas outlet pipe to make it closer to the exhaust port of the furnace tube, thereby reducing the gas concentration gradient descent rate and improving the uniformity within the wafer.
By adjusting the gas exhaust location, the rate of decrease in gas concentration was reduced, improving uniformity within the wafer and increasing product yield.
Smart Images
Figure CN116815163B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of heat treatment technology, and in particular to an air inlet pipe and a furnace tube for use in heat treatment processes. Background Technology
[0002] In heat treatment processes, such as atomic layer deposition (ALD), the deposition thickness and uniformity are primarily determined by the adsorption of the first precursor on the wafer surface. However, due to the airflow direction, the gas at the top flows along a parabolic path towards the furnace tube's exhaust port, resulting in a higher rate of concentration decrease at the wafer edge and center. This leads to poor uniformity within the wafer, causing significant differences in THK (thickness) and STDEV (standard deviation), thus affecting product yield. Therefore, improving the poor uniformity within the wafer during heat treatment is a technical problem that needs to be solved by those skilled in the art. Summary of the Invention
[0003] The purpose of this application is to provide an air inlet pipe and furnace tube for a furnace tube used in a heat treatment process, thereby improving uniformity within the wafer.
[0004] To achieve the above objectives, this application provides an air inlet pipe for a furnace tube, comprising: an air inlet pipe and an air outlet position adjustment device;
[0005] The air intake pipe is equipped with an air inlet and multiple air outlets;
[0006] The gas outlet position adjustment device is connected to the gas inlet pipe and is used to adjust the gas outlet position so that the outlet position is close to the exhaust port of the furnace tube.
[0007] Optionally, the air outlet position adjustment device includes: a plurality of air outlet pipes; each air outlet pipe is connected to each air outlet for discharging gas at the air outlet; the discharge position corresponds to the length of the air outlet pipe.
[0008] Optionally, the length of the air outlet pipe is 1mm-12mm, including the values at both ends.
[0009] Optionally, the air outlet position adjustment device includes: a plurality of air outlet pipe groups; the length of each air outlet pipe group increases sequentially in the direction away from the air inlet; each air outlet pipe group includes at least one air outlet pipe.
[0010] Optionally, the length of each of the air outlet pipes increases sequentially in the direction away from the air inlet.
[0011] Optionally, the angle between the outlet pipe and the pipe wall in the direction away from the inlet is less than 90°.
[0012] Optionally, the air outlet position adjustment device includes: multiple air outlet pipe groups; the degree of the included angle in each air outlet pipe group decreases sequentially along the direction away from the air inlet; each air outlet pipe group includes at least one air outlet pipe.
[0013] Optionally, the degree of each of the included angles decreases sequentially along the direction away from the air inlet.
[0014] Optionally, all included angles in the direction away from the air inlet are less than 90°, starting from the air outlet pipe connected to the air outlet at the center position.
[0015] To achieve the above objectives, this application also provides a furnace tube, including an air inlet pipe as described above.
[0016] This application provides an air inlet pipe for a furnace tube, comprising: an air inlet pipe and an air outlet position adjustment device; the air inlet pipe is provided with an air inlet and multiple air outlets; the air outlet position adjustment device is connected to the air inlet pipe and is used to adjust the exhaust position of the gas at the air outlet so that the exhaust position is close to the exhaust port of the furnace tube.
[0017] Obviously, this application connects an outlet position adjustment device to the inlet pipe, adjusting the outlet position of the gas at the outlet on the inlet pipe to bring the outlet position closer to the furnace tube's exhaust port. This shifts the entire gas flow parabola towards the furnace tube's exhaust port, reducing the rate of decrease in gas concentration and mitigating the impact of the gas flow parabola, thereby improving wafer uniformity and ultimately increasing product yield. This application also provides a furnace tube with the aforementioned beneficial effects. Attached Figure Description
[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.
[0019] Figure 1 This is a schematic diagram of the gas flow direction inside a traditional atomic layer deposition furnace tube;
[0020] Figure 2 A schematic diagram of the air inlet pipe of an atomic layer deposition furnace tube provided in this application embodiment;
[0021] Figure 3 A partially enlarged schematic diagram of the air inlet pipe of an atomic layer deposition furnace tube provided in an embodiment of this application;
[0022] Figure 4 This application provides a schematic diagram of gas flow direction inside an atomic layer deposition furnace tube.
[0023] The annotations in the attached figures are explained as follows:
[0024] 1-Inlet pipe; 11-Inlet; 12-Outlet; 2-Outlet pipe; θ-Angle; 3-Inlet of furnace tube; 4-Outlet of furnace tube. Detailed Implementation
[0025] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0026] The furnace tubes provided in this application are furnace tubes used in heat treatment processes, specifically atomic layer deposition furnace tubes. The gas inlet pipe of the furnace tube may include: a gas inlet pipe 1 and a gas outlet position adjustment device;
[0027] The air intake pipe 1 is provided with an air inlet 11 and multiple air outlets 12;
[0028] The gas outlet position adjustment device is connected to the gas inlet pipe 1 and is used to adjust the gas outlet position at the gas outlet 12 so that the outlet position is close to the exhaust port 4 of the furnace tube.
[0029] This embodiment does not limit the specific type of gas outlet position adjustment device, as long as it can ensure that the gas discharge position at the gas outlet 12 can be adjusted so that the discharge position is close to the exhaust port 4 of the furnace tube. For example, the gas outlet position adjustment device may include: multiple gas outlet pipes 2; each gas outlet pipe 2 is connected to each gas outlet 12 for discharging gas at the gas outlet 12; the discharge position corresponds to the length of the gas outlet pipe 2. It should be noted that the path of the gas discharged from the gas outlet 12 of the gas inlet pipe 1 to the exhaust port 4 of the atomic deposition furnace tube is parabolic. Therefore, the gas concentration gradient decrease rate is greater the further away from the gas outlet. That is, the gas concentration gradient decrease rate in the direction away from the furnace tube exhaust port 4 will be lower than the gas concentration gradient decrease rate in the direction close to the furnace tube exhaust port 4. A lower gas concentration gradient decrease rate means better uniformity. In this embodiment, one end of the gas outlet pipe 2 is connected to the gas outlet 12 of the gas inlet pipe 1. The other end of the gas outlet pipe 2 is provided with a gas outlet for discharging gas. The gas discharge position can be moved from the gas outlet 12 to the gas outlet of the gas outlet pipe 2 through the gas outlet pipe 2, so as to move the entire airflow parabola towards the exhaust port 4 closer to the furnace tube. That is, the part with a high gas concentration gradient decrease rate is moved towards the exhaust port 4 closer to the furnace tube, which can achieve the purpose of reducing the gas concentration gradient decrease rate.
[0030] Because each slot used to fix the wafer in this embodiment requires a corresponding vent 12, the specific number of vent 12 is determined by the specific number of slots, and the corresponding number of vent pipes 2 is also determined by the number of slots. This embodiment does not limit the specific length of the vent pipe 2, and the specific length of the vent pipe 2 can be determined according to the actual situation. For example, the length of the vent pipe 2 can be 1mm-12mm, including the values at both ends.
[0031] It should be noted that the gas concentration gradient decrease rate of the parabolic airflow discharged from the outlet 12 at the top of the inlet pipe 1 is higher than that of the parabolic airflow discharged from the outlet 12 at the bottom of the inlet pipe 1. Furthermore, to accommodate the difference in gas concentration gradient decrease rate between the top and bottom, the outlet position adjustment device in this embodiment may include: multiple outlet pipe groups; the length of each outlet pipe group increases sequentially in the direction away from the inlet 11; each outlet pipe group includes at least one outlet pipe 2. It should be noted that this embodiment, while reducing the gas concentration gradient decrease rate at a single outlet 12 and improving wafer uniformity, can also improve wafer uniformity by designing outlet pipes 2 to different lengths to reduce the difference in gas concentration gradient decrease rate between the top and bottom. This embodiment does not limit the specific length increment; the specific length increment can be determined according to the actual situation. This embodiment does not limit whether the number of exhaust pipes 2 included in each exhaust pipe group is the same. For example, the number of exhaust pipes 2 included in each exhaust pipe group can be the same; or the number of exhaust pipes 2 included in each exhaust pipe group can decrease sequentially in the direction away from the air inlet 11. This embodiment does not limit the specific number of exhaust pipes 2 included in each exhaust pipe group, because the smaller the distance between adjacent exhaust pipes 2, the smaller the difference in the flow direction of the gas discharged from the exhaust pipes 2. Therefore, the specific number of exhaust pipes 2 included in each exhaust pipe group can be determined according to the actual distance between adjacent exhaust pipes 2. Furthermore, in this embodiment, the length of each exhaust pipe 2 can increase sequentially in the direction away from the air inlet 11, that is, by sequentially increasing the length of each exhaust pipe 2, the difference between the wafer layers from the bottom wafer to the top wafer is minimized.
[0032] Furthermore, to improve uniformity within the wafer, in this embodiment, the angle θ between the exhaust pipe 2 and the pipe wall in the direction away from the inlet 11 can be less than 90°. It should be noted that in this embodiment, the exhaust pipe 2 is designed with an upward angle, which allows the airflow to have an upward initial velocity when exiting the exhaust pipe 2, thus counteracting the effects of the airflow parabola and improving uniformity within the wafer. This embodiment does not limit the specific angle θ; the specific angle θ can be determined according to actual conditions. It should be noted that when the angle θ between the outlet pipe 2 and the pipe wall in the direction away from the inlet 11 is equal to 90°, the discharge position corresponds to the length of the outlet pipe 2, that is, the discharge position is determined by the length of the outlet pipe 2; when the angle θ between the outlet pipe 2 and the pipe wall in the direction away from the inlet 11 is less than 90°, the discharge position corresponds to both the length of the outlet pipe 2 and the angle θ between the outlet pipe 2 and the pipe wall in the direction away from the inlet 11, that is, the discharge position is jointly determined by the length of the outlet pipe 2 and the angle θ between the outlet pipe 2 and the pipe wall in the direction away from the inlet 11.
[0033] Furthermore, to improve inter-wafer uniformity, the gas outlet position adjustment device in this embodiment may include: multiple gas outlet pipe groups; the included angle θ in each gas outlet pipe group decreases sequentially along the direction away from the gas inlet 11; each gas outlet pipe group includes at least one gas outlet pipe 2. It should be noted that this embodiment, while offsetting the influence of the airflow parabola at a single gas outlet 12 and improving intra-wafer uniformity, also improves inter-wafer uniformity by designing the gas outlet pipes 2 at different angles to reduce the difference in the gas concentration gradient between the top and bottom ends, based on the difference in the gas concentration gradient decrease rate between the top and bottom ends. This embodiment does not limit the specific angle step size for the sequential decrease; the specific angle step size can be determined according to the actual situation. This embodiment does not limit whether the number of gas outlet pipes 2 included in each gas outlet pipe group is the same; for example, the number of gas outlet pipes 2 included in each gas outlet pipe group can be the same; or the number of gas outlet pipes 2 included in each gas outlet pipe group can decrease sequentially along the direction away from the gas inlet 11. This embodiment does not limit the specific number of exhaust pipes 2 included in the exhaust pipe group, because the smaller the distance between adjacent exhaust pipes 2, the smaller the difference in the flow direction of the gas discharged from the exhaust pipe 2. Therefore, the specific number of exhaust pipes 2 included in the exhaust pipe group can be determined according to the actual distance between adjacent exhaust pipes 2. Furthermore, in this embodiment, the degree of each included angle θ decreases sequentially along the direction away from the air inlet 11. That is, by sequentially decreasing the degree of each included angle θ, the difference between the wafers in each layer from the bottom wafer to the top wafer is minimized. Furthermore, considering that the influence of the airflow parabola at the exhaust port 12, which is closer to the air inlet 11 (i.e., the bottom), is smaller, in this embodiment, the exhaust pipe 2 connected to the exhaust port 12 at the center position can be taken as the starting point, and all included angles θ in the direction away from the air inlet 11 can be less than 90°.
[0034] Based on the above embodiments, this application connects an outlet position adjustment device to the inlet pipe 1. The outlet position adjustment device adjusts the outlet position of the gas at the outlet 12 on the inlet pipe 1 so that the outlet position is close to the exhaust port 4 of the furnace tube. That is, the entire airflow parabola is moved towards the exhaust port 4 of the furnace tube, so as to reduce the step decrease rate of gas concentration, thereby weakening the influence of the airflow parabola, improving the uniformity within the wafer, and thus improving the yield of the product.
[0035] Please refer to Figure 2 and Figure 3 , Figure 2 This is a schematic diagram of the air inlet pipe of an atomic layer deposition furnace tube provided in an embodiment of this application. Figure 3 This is a partially enlarged schematic diagram of the air inlet pipe of an atomic layer deposition furnace tube provided in an embodiment of this application. The air inlet pipe may include: an air inlet pipe 1 and an air outlet position adjustment device.
[0036] The air intake pipe 1 is provided with an air inlet 11 and multiple air outlets 12;
[0037] The gas outlet position adjustment device is connected to the gas inlet pipe 1 and is used to adjust the gas outlet position at the gas outlet 12 so that the outlet position is close to the exhaust port 4 of the furnace tube.
[0038] The air outlet position adjustment device includes: multiple air outlet pipe groups; the length of each air outlet pipe group increases sequentially in the direction away from the air inlet 11; each air outlet pipe group includes at least one air outlet pipe 2; taking the air outlet pipe 2 connected to the air outlet 12 at the center position as the starting point, all included angles θ in the direction away from the air inlet 11 are less than 90°; each air outlet pipe 2 is connected to each air outlet 12 for discharging gas at the air outlet 12; the discharge position corresponds to the length of the air outlet pipe 2.
[0039] Based on the above embodiments, this application connects an exhaust pipe 2 to the exhaust port 12 of the intake pipe 1. The exhaust pipe 2 moves the gas discharge position from the exhaust port 12 to the exhaust port of the exhaust pipe 2, that is, moves the entire airflow parabola towards the exhaust port 4 near the furnace tube. This can reduce the gas concentration gradient descent rate. Furthermore, the exhaust pipe 2 is designed with an upward angle, so that the airflow has an upward initial velocity when it is discharged from the exhaust pipe 2, which can counteract the influence of the airflow parabola and thus improve the uniformity within the wafer. At the same time, based on the difference in the gas concentration gradient descent rate between the top and bottom ends, by designing the exhaust pipe 2 with different lengths and different angles, the difference in the gas concentration gradient descent rate between the top and bottom ends can be weakened, which can also improve the uniformity between wafers and thus improve the product yield.
[0040] This application embodiment also provides a furnace tube, which may include: an air inlet pipe as described above.
[0041] It should be noted that, since each slot used to fix the wafer in this embodiment needs to correspond to an exhaust port 12, when the air inlet pipe is placed from the air inlet 3 of the furnace tube into the furnace tube, it is necessary to ensure that the position of each exhaust pipe 2 corresponds to the position of the slot.
[0042] Based on the above-described embodiment of the furnace tube's inlet pipe, this application connects an outlet position adjustment device to the inlet pipe 1. This device adjusts the gas outlet position at the outlet 12 on the inlet pipe 1, bringing the outlet position closer to the furnace tube's exhaust port 4. This shifts the entire airflow parabola towards the exhaust port 4, reducing the rate of decrease in gas concentration and mitigating the impact of the airflow parabola. This improves wafer uniformity and ultimately increases product yield. The furnace tube provided in this application, including the aforementioned inlet pipe, also possesses the aforementioned beneficial effects.
[0043] The following examples illustrate the effects of the air intake pipe based on the aforementioned furnace tubes. Please refer to them. Figure 3 , Figure 2 A schematic diagram of the air inlet pipe of an atomic layer deposition furnace tube provided in this application embodiment; Figure 3 A partially enlarged schematic diagram of the air inlet pipe of an atomic layer deposition furnace tube provided in an embodiment of this application; Figure 4 This application provides a schematic diagram of gas flow direction inside an atomic layer deposition furnace tube.
[0044] In this embodiment, each air outlet 12 on the air inlet pipe 1 is connected to an air outlet pipe 2. Every 10 air outlet pipes 2 from the bottom to the top form an air outlet pipe group. The length of the air outlet pipe 2 in each air outlet pipe group increases in increments of 1 mm, from 1 mm to 12 mm (the length of the air outlet pipes 2 in each air outlet pipe group is the same). Starting from the air outlet pipe 2 at the center position, each air outlet pipe 2 forms a 5° angle θ with the pipe wall.
[0045] In this embodiment, an exhaust pipe 2 is connected to the exhaust port 12 of the intake pipe 1. Based on the difference in the rate of decrease in gas concentration between the top and bottom ends, the exhaust pipe 2 is designed with a progressively increasing length. This moves the gas discharge position from the exhaust port 12 to the exhaust port of the exhaust pipe 2, shifting the overall airflow parabola towards the exhaust port 4 near the furnace tube. This reduces the rate of decrease in gas concentration and weakens the difference in the rate of decrease between the top and bottom ends, thus improving both intra-wafer and inter-wafer uniformity. Simultaneously, the exhaust pipe 2 is designed with an upward angle, giving the airflow an upward initial velocity upon exiting the exhaust pipe 2, counteracting the effects of the airflow parabola and further improving intra-wafer uniformity. The gas flow direction of the intake pipe and the gas concentration distribution on the wafer based on this embodiment are as follows: Figure 4 As shown. Furthermore, because the wafer boat is constantly rotating during the process, the gas concentration is high at the wafer edges and low at the center, resulting in a concentric circle shape. Figure 1 Compared to the gas flow direction inside a traditional atomic layer deposition furnace tube, the gas flow direction discharged from a single gas outlet pipe 2 in this embodiment is gentler, that is, the gas concentration gradient decrease rate is lower, thus resulting in better uniformity within the wafer; at the same time, the gas flow direction discharged from the top gas outlet pipe 2 is also closer to that discharged from the bottom gas outlet pipe 2, thus resulting in better uniformity between wafers.
[0046] This document uses specific examples to illustrate the principles and implementation methods of this application. The various embodiments are progressive, with each embodiment focusing on its differences from others. Similar or identical parts between embodiments can be referred to interchangeably. The descriptions of the embodiments above are merely illustrative of the method and core ideas of this application. For those skilled in the art, various improvements and modifications can be made to this application without departing from its principles, and these improvements and modifications also fall within the scope of protection of the claims of this application.
[0047] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.
Claims
1. An air inlet duct for a furnace tube, characterized in that include: Air intake pipe and air outlet position adjustment device; The air intake pipe is equipped with an air inlet and multiple air outlets; The air outlet position adjustment device includes: multiple air outlet pipe groups; The length of each of the aforementioned air outlet pipe groups increases sequentially along the direction away from the air inlet; the direction away from the air inlet is from bottom to top; each of the aforementioned air outlet pipe groups includes at least one of the aforementioned air outlet pipes; Each of the gas outlet pipes is connected to each of the gas outlets for discharging gas from the gas outlets; the gas discharge position at the gas outlet corresponds to the length of the gas outlet pipe, so that the discharge position is close to the exhaust port of the furnace tube.
2. The air inlet pipe of the furnace tube according to claim 1, characterized in that, The length of the air outlet pipe is 1mm-12mm, including the values at both ends.
3. The air inlet pipe of the furnace tube according to claim 1, characterized in that, The length of each of the air outlet pipes increases sequentially in the direction away from the air inlet.
4. The air inlet pipe of the furnace tube according to claim 1, characterized in that, The angle between the outlet pipe and the pipe wall in the direction away from the inlet is less than 90°.
5. The air inlet pipe of the furnace tube according to claim 4, characterized in that, The angles in each of the air outlet pipe groups decrease sequentially in the direction away from the air inlet.
6. The air inlet pipe of the furnace tube according to claim 5, characterized in that, The degrees of each of the included angles decrease sequentially along the direction away from the air inlet.
7. The air inlet pipe of the furnace tube according to claim 4, characterized in that, Starting from the air outlet pipe connected to the air outlet at the center position, all included angles in the direction away from the air inlet are less than 90°.
8. A furnace tube, characterized in that, The gas inlet pipe includes the furnace tube as described in any one of claims 1 to 7.