A furnace tube apparatus tail gas pressure control device

Abstract

The utility model discloses a kind of furnace tube equipment tail gas pressure control device, it is related to the field of semiconductor manufacturing technology, including tail gas inlet pipe, tail gas outlet pipe, transition chamber, piston cavity, piston, nitrogen input pipe and pressure sensor;The one end of transition chamber is equipped with first communication hole, and the other end of transition chamber is equipped with second communication hole and third communication hole;The cavity bottom of piston cavity is equipped with the air inlet that can be communicated with second communication hole, and the cavity wall of piston cavity close to second communication hole is equipped with multiple air outlets that can be communicated with transition chamber at interval;Nitrogen input by nitrogen input pipe is input into the gap between piston and piston cavity by the communication pipe in the middle part of piston cavity;Pressure sensor is used to detect the pressure in tail gas inlet pipe, and based on the preset pressure threshold range, the stroke of piston in piston cavity is controlled. Through the cooperation of transition chamber, piston cavity and piston, pressure sensor control and nitrogen input, further improve the control tail gas pressure precision.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor manufacturing technology, specifically to a furnace tube equipment exhaust gas pressure control device. Background Technology

[0002] In semiconductor manufacturing, furnace tube equipment is a key piece of equipment used for heat treatment. Its main function is to heat silicon wafers to achieve processes such as oxidation, diffusion, and deposition. The process used is APCVD (Atmospheric Pressure Chemical Vapor Deposition), which is an atmospheric pressure chemical vapor deposition process.

[0003] A key component of furnace tube equipment is the reaction tube, which houses the silicon wafer and exposes it to a specific chemical vapor environment for chemical vapor deposition or other heat treatment processes. The reaction tube is connected to an ignition device, through which water vapor generated by the high-temperature reaction is introduced. The ignition device is a cylindrical tube through which gases or chemicals pass and react at a specific temperature; it is typically made of quartz, which can withstand high temperatures and remain chemically inert.

[0004] In existing technologies, when using wet oxidation processes to treat the exhaust gas from APCVD processes, the current exhaust gas pressure control methods are mostly quite simple. This makes it difficult to precisely adjust the pressure based on the actual pressure inside the exhaust gas inlet pipe, resulting in large fluctuations in exhaust gas pressure. This fails to meet the stringent requirements for exhaust gas pressure stability in semiconductor manufacturing processes. Furthermore, because the exhaust gas contains a large amount of water vapor, this water vapor easily condenses inside the exhaust gas pipe during emission, forming condensate. If this condensate is not drained promptly, it will accumulate inside the exhaust gas pipe, not only affecting the normal emission of the exhaust gas but also potentially damaging the exhaust gas pressure control device, reducing its control accuracy and lifespan.

[0005] Therefore, how to provide a high-precision exhaust gas pressure control device for furnace tube equipment is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the purpose of this application is to overcome the shortcomings of the prior art and propose a furnace tube equipment exhaust gas pressure control device to solve the problems mentioned above in the background art.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is: a tail gas pressure control device for furnace tube equipment, including a tail gas inlet pipe, a tail gas outlet pipe, a transition chamber, a piston cavity, a piston, a nitrogen input pipe, and a pressure sensor. One end of the transition chamber is provided with a first connecting hole, which is connected to the tail gas outlet pipe. The other end of the transition chamber is provided with a second connecting hole and a third connecting hole located on the same axis. The second connecting hole is connected to the tail gas inlet pipe. The piston cavity passes through the third connecting hole and abuts against the second connecting hole. An air inlet is provided at the bottom of the piston cavity near the second connecting hole, which can communicate with the second connecting hole. Multiple circumferentially distributed air outlets are spaced apart on the cavity wall of the piston cavity near the second connecting hole, and these multiple air outlets can communicate with the transition chamber. Nitrogen gas input through the nitrogen input pipe enters the gap between the piston and the piston cavity through the connecting pipe in the middle of the piston cavity. The pressure sensor is used to detect the pressure inside the tail gas inlet pipe and, based on a preset pressure threshold range, controls the stroke of the piston within the piston cavity.

[0008] Preferably, the piston includes a piston cylinder with an internal cavity, a spring, a connecting rod, a cover plate with a through hole, and a linear motor. The cover plate is fixed to the end of the piston cylinder away from the air inlet. The spring is located inside the cavity of the piston cylinder and fixed to the bottom of the cavity. The other end of the spring is fixed to the connecting rod. The other end of the connecting rod passes through the through hole of the cover plate and is fixed to the output end of the linear motor.

[0009] Preferably, a groove is provided at the end of the piston cavity away from the second connecting hole, and the cover plate is adapted to the groove. When the piston cylinder moves toward the air inlet, a sealed space can be formed between the cover plate and the groove.

[0010] Preferably, the inner wall of the piston cavity is provided with an annular groove along its axial direction, and a plurality of connecting holes are provided on the annular groove. The connecting pipe is connected to at least one connecting hole. When the nitrogen input pipe inputs nitrogen into the connecting pipe, a nitrogen gas film is formed between the piston and the piston cavity.

[0011] Preferably, when the pressure value in the exhaust gas intake pipe is within a preset pressure threshold range, the linear motor stops moving; when the pressure value in the exhaust gas intake pipe is greater than the maximum value of the preset pressure threshold range, the linear motor rotates and drives the piston cylinder to move towards the cover plate; when the pressure value in the exhaust gas intake pipe is less than the minimum value of the preset pressure threshold range, the linear motor rotates and drives the piston cylinder to move towards the air inlet.

[0012] Preferably, a pressure reducing valve is provided between the nitrogen input pipe and the connecting pipe, the pressure reducing valve being used to reduce the pressure of the nitrogen input pipe before inputting it into the connecting pipe.

[0013] Preferably, the transition chamber is also connected to a drain pipe, the inlet of which is located in the lowest region of the transition chamber relative to the horizontal plane, and the drain pipe is used to discharge condensate from the exhaust gas inlet pipe.

[0014] Preferably, a mounting bracket is provided on one side of the piston cavity, the linear motor is fixed on the mounting bracket, a limit block is fixed on the connecting rod, and a first limit spring and a second limit spring that are mirror-arranged are fixed on the mounting bracket, forming a limiting space between the first limit spring and the second limit spring.

[0015] The beneficial effects achieved by this utility model due to the adoption of the above technical solution are as follows: 1. By using a pressure sensor to detect the pressure inside the exhaust gas intake pipe in real time, and precisely controlling the stroke of the piston in the piston chamber based on a preset pressure threshold range, the exhaust gas pressure can be precisely regulated. This effectively solves the problem of large exhaust gas pressure fluctuations in existing technologies and meets the stringent requirements for exhaust gas pressure stability in semiconductor manufacturing processes.

[0016] Second, the structure that forms a nitrogen gas film between the piston and the piston cavity not only reduces the frictional resistance during piston movement and improves the response speed and control accuracy of the device, but also plays a good sealing role, preventing exhaust gas leakage from polluting the environment.

[0017] Third, the structure of the transition chamber connected to the drain pipe can promptly discharge the condensate in the exhaust gas intake pipe, avoiding the adverse effects of condensate accumulation in the exhaust gas pipeline on normal exhaust gas emission and exhaust gas pressure control device, and further improving the control accuracy and service life of the device.

[0018] Fourth, the piston is configured as a combination of a piston cylinder with an internal cavity, a spring, a connecting rod, a cover plate with a through hole, and a linear motor, which enables the piston to remain stable during movement and is easy to control and adjust, providing a strong guarantee for the high-precision control of the device.

[0019] Fifth, the first and second limiting springs installed on the mounting bracket form an effective limiting space for the limiting block on the connecting rod, preventing device damage or control failure caused by the piston exceeding its stroke range during movement, thus improving the safety and reliability of the device. Attached Figure Description

[0020] Figure 1 This is a schematic cross-sectional view of the exhaust gas pressure control device for furnace tube equipment according to the present invention. Figure 2 This is a rear view structural schematic diagram of a furnace tube equipment tail gas pressure control device according to the present invention. Figure 3 This is a structural schematic diagram of the assembly drawing of a tail gas pressure control device for furnace tube equipment according to the present invention; Figure 4 for Figure 3 A schematic diagram of the structure at point AA.

[0021] The attached diagram lists the components represented by each number as follows: 1. Exhaust gas inlet pipe; 2. Exhaust gas outlet pipe; 3. Transition chamber; 31. First connecting hole; 32. Second connecting hole; 33. Third connecting hole; 34. Drain pipe; 4. Piston chamber; 41. Inlet; 42. Outlet; 43. Connecting pipe; 44. Settling tank; 45. Annular groove; 46. Connecting hole; 5. Piston; 51. Piston cylinder; 52. Spring; 53. Connecting rod; 54. Cover plate; 55. Linear motor; 6. Nitrogen input pipe; 61. Pressure reducing valve; 7. Pressure sensor; 8. Mounting bracket; 81. Limiting block; 82. First limiting spring; 83. Second limiting spring; 9. Outer shell. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] The core of this invention is to provide a high-precision furnace tube equipment exhaust gas pressure control device to solve the problem of inaccurate control precision of existing exhaust gas pressure control devices when using wet oxidation process to treat exhaust gas of APCVD process in semiconductor manufacturing.

[0024] The present invention will be described in detail with the following embodiments: Example

[0025] refer to Figure 1-4 A furnace tube equipment exhaust gas pressure control device, such as Figure 1 As shown, it includes an exhaust gas inlet pipe 1, an exhaust gas outlet pipe 2, a transition chamber 3, a piston chamber 4, a piston 5, a nitrogen input pipe 6, and a pressure sensor 7. like Figure 1 , 4As shown, one end of the transition chamber 3 is provided with a first connecting hole 31, which is connected to the exhaust gas outlet pipe 2. The other end of the transition chamber 3 is provided with a second connecting hole 32 and a third connecting hole 33 located on the same axis. The coaxial structure of the second connecting hole 32 and the third connecting hole 33 reduces the resistance when the exhaust gas flows. The second connecting hole 32 is connected to the exhaust gas inlet pipe 1. The piston chamber 4 passes through the third connecting hole 33 and abuts against the second connecting hole 32. A sealing gasket is provided at the connection between the third connecting hole 33 and the piston chamber 4 to prevent leakage in the transition chamber 3. like Figure 1 As shown, the piston cavity 4 has an air inlet 41 at the bottom near the second connecting hole 32, which can communicate with the second connecting hole 32. The piston cavity 4 has multiple circumferentially distributed air outlets 42 at intervals on the cavity wall near the second connecting hole 32. The multiple air outlets 42 can communicate with the transition chamber 3. Nitrogen gas input by nitrogen input pipe 6 is input into the gap between piston 5 and piston cavity 4 through connecting pipe 43 in the middle of piston cavity 4. Specifically, the inner wall of the piston cavity 4 is provided with an annular groove 45 along its axial direction. Multiple connecting holes 46 are provided on the annular groove 45. The multiple connecting holes 46 are distributed at intervals around the annular groove 45 and connect the gap between the piston 5 and the piston cavity 4. The connecting pipe 43 is connected to at least one connecting hole 46. When nitrogen gas is introduced into the connecting pipe 43 by the nitrogen gas input pipe 6, a nitrogen gas film is formed between the piston 5 and the piston cavity 4, forming "air flotation" and reducing the friction between the piston 5 and the piston cavity 4.

[0026] To improve the accuracy of pressure control, such as Figure 1 As shown, the piston 5 is configured as a piston cylinder 51 with an internal cavity, a spring 52, a connecting rod 53, a cover plate 54 with a through hole, and a linear motor 55. The cover plate 54 is fixed at the end of the piston cylinder 51 away from the air inlet 41. The spring 52 is located in the cavity of the piston cylinder 51 and is fixed at the bottom of the cavity of the piston cylinder 51. The other end of the spring 52 is fixed to the connecting rod 53. The other end of the connecting rod 53 passes through the through hole of the cover plate 54 and is fixed to the output end of the linear motor 55.

[0027] In the structure of the piston 5 described above, the spring 52 provides motion damping when the piston cylinder 51 moves, suppressing sudden fluctuations in the process exhaust gas pressure, and the through hole of the cover plate 54 facilitates the transmission between the connecting rod 53 and the linear motor 55.

[0028] In practical use, such as Figure 1As shown, when the operation starts, the process exhaust gas enters from the exhaust gas inlet pipe 1, and nitrogen is introduced simultaneously or in advance from the nitrogen inlet pipe 6. After passing through the second connecting hole 32, the process exhaust gas exerts a rightward force on the piston cylinder 51 through the air inlet 41, pushing the piston cylinder 51 to move to the right. The process exhaust gas enters the piston cavity 4, and then enters the transition chamber 3 through the air outlet 42. After passing through the first connecting hole 31, it enters the exhaust gas outlet pipe 2 and is discharged.

[0029] In the above process, after the process exhaust gas enters the piston cavity 4 and the transition chamber 3, the water vapor carried in the process exhaust gas condenses to produce condensate. In order to avoid the accumulation of condensate affecting the emission of process exhaust gas and the pressure control effect, a drain pipe 34 is also provided in the transition chamber 3. The inlet of the drain pipe 34 is located in the lowest area of ​​the transition chamber 3 relative to the horizontal plane, and is used to discharge the condensate in the exhaust gas inlet pipe 1.

[0030] like Figure 1 As shown, pressure sensor 7 is used to detect the pressure inside the exhaust gas intake pipe 1. It should be noted that the detection head of pressure sensor 7 is connected inside the exhaust gas intake pipe 1. The main body of pressure sensor 7 is as follows... Figure 1 As shown, it is installed on the right side to reduce the space it occupies; The pressure sensor 7 is based on a preset pressure threshold range, which can be adjusted according to actual process requirements to control the stroke of the piston 5 in the piston chamber 4.

[0031] Specifically, during operation, when the pressure value inside the exhaust gas inlet pipe 1 is within the preset pressure threshold range, the linear motor 55 stops moving, and the process exhaust gas flows into the inlet 41 through the exhaust gas inlet pipe 1 and enters the exhaust gas outlet pipe 2 through the outlet 42; when the pressure value inside the exhaust gas inlet pipe 1 is greater than the maximum value of the preset pressure threshold range, the linear motor 55 rotates and drives the piston cylinder 51 to move towards the cover plate 54. Due to the rightward movement of the piston cylinder 51, the process exhaust gas entering the piston cavity 4 through the inlet 41 is subjected to the resistance of the piston cylinder 51. The smaller pressure in the exhaust gas inlet pipe 1 causes the flow rate at the outlet 42 to increase, and the pressure value in the exhaust gas inlet pipe 1 to decrease to the preset pressure threshold. When the pressure value in the exhaust gas inlet pipe 1 is less than the minimum value of the preset pressure threshold range, the linear motor 55 rotates and drives the piston cylinder 51 to move towards the inlet 41. As the piston cylinder 51 moves to the left, the process exhaust gas entering the piston cavity 4 through the inlet 41 is subject to greater resistance from the piston cylinder 51, which causes the flow rate at the outlet 42 to decrease, and the pressure value in the exhaust gas inlet pipe 1 to increase to the preset pressure threshold.

[0032] Based on the above structure, to further improve the pressure control effect and prevent the piston cylinder 51 from colliding and hitting the bottom due to excessive instantaneous speed during movement, such as... Figure 1As shown, a groove 44 is provided at the end of the piston cavity 4 away from the second connecting hole 32. The cover plate 54 is adapted to the groove 44. When the piston cylinder 51 moves toward the air inlet 41, that is, when the piston cylinder 51 moves to the left, a sealed space can be formed between the cover plate 54 and the groove 44. When the sealed space is compressed, the air inside it has a rightward force on the cover plate 54, which plays a damping role.

[0033] Furthermore, such as Figure 2 As shown, a mounting bracket 8 is also provided on one side of the piston cavity 4. The linear motor 55 is fixed on the mounting bracket 8. A limit block 81 is fixed on the connecting rod 53. A first limit spring 82 and a second limit spring 83 are fixed on the mounting bracket 8 in a mirror arrangement. A limiting space of the limit block 81 is formed between the first limit spring 82 and the second limit spring 83. This limiting space further prevents the piston cylinder 51 from going out of control when it moves.

[0034] like Figure 1 , 2 As shown, a pressure reducing valve 61 is installed between the nitrogen input pipe 6 and the connecting pipe 43. The pressure reducing valve 61 is used to reduce the pressure of the nitrogen input pipe 6 before it is introduced into the connecting pipe 43, so as to ensure that "air flotation" always exists during use.

[0035] It should be noted that, in this document, 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.

[0036] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A tail gas pressure control device for furnace tube equipment, characterized in that, It includes an exhaust gas inlet pipe (1), an exhaust gas outlet pipe (2), a transition chamber (3), a piston chamber (4), a piston (5), a nitrogen input pipe (6), and a pressure sensor (7). One end of the transition chamber (3) is provided with a first connecting hole (31), which is connected to the exhaust gas outlet pipe (2). The other end of the transition chamber (3) is provided with a second connecting hole (32) and a third connecting hole (33) located on the same axis. The second connecting hole (32) is connected to the exhaust gas inlet pipe (1). The piston cavity (4) passes through the third connecting hole (33) and abuts against the second connecting hole (32). The piston cavity (4) has an air inlet (41) at the bottom near the second connecting hole (32) that can communicate with the second connecting hole (32). The piston cavity (4) has multiple circumferentially distributed air outlets (42) at intervals on the cavity wall near the second connecting hole (32). The multiple air outlets (42) can communicate with the transition chamber (3). The nitrogen gas input by the nitrogen input pipe (6) is input into the gap between the piston (5) and the piston cavity (4) through the connecting pipe (43) in the middle of the piston cavity (4). The pressure sensor (7) is used to detect the pressure inside the exhaust gas intake pipe (1) and control the stroke of the piston (5) in the piston cavity (4) based on a preset pressure threshold range.

2. The furnace tube equipment tail gas pressure control device according to claim 1, characterized in that, The piston (5) includes a piston cylinder (51) with an internal cavity, a spring (52), a connecting rod (53), a cover plate (54) with a through hole, and a linear motor (55). The cover plate (54) is fixed to one end of the piston cylinder (51) away from the air inlet (41). The spring (52) is located inside the cavity of the piston cylinder (51) and fixed to the bottom of the cavity of the piston cylinder (51). The other end of the spring (52) is fixed to the connecting rod (53). The other end of the connecting rod (53) passes through the through hole of the cover plate (54) and is fixed to the output end of the linear motor (55).

3. The furnace tube equipment tail gas pressure control device according to claim 2, characterized in that, The piston cavity (4) is provided with a sink groove (44) at one end away from the second connecting hole (32). The cover plate (54) is adapted to the sink groove (44). When the piston cylinder (51) moves toward the air inlet (41), a sealed space can be formed between the cover plate (54) and the sink groove (44).

4. The furnace tube equipment exhaust gas pressure control device according to claim 3, characterized in that, The inner wall of the piston cavity (4) is provided with an annular groove (45) along its axial direction. Multiple connecting holes (46) are provided on the annular groove (45). The connecting pipe (43) is connected to at least one connecting hole (46). When the nitrogen input pipe (6) inputs nitrogen into the connecting pipe (43), a nitrogen gas film is formed between the piston (5) and the piston cavity (4).

5. The furnace tube equipment tail gas pressure control device according to claim 4, characterized in that, When the pressure value in the exhaust gas inlet pipe (1) is within the preset pressure threshold range, the linear motor (55) stops moving; when the pressure value in the exhaust gas inlet pipe (1) is greater than the maximum value of the preset pressure threshold range, the linear motor (55) rotates and drives the piston cylinder (51) to move towards the cover plate (54); when the pressure value in the exhaust gas inlet pipe (1) is less than the minimum value of the preset pressure threshold range, the linear motor (55) rotates and drives the piston cylinder (51) to move towards the air inlet (41).

6. The furnace tube equipment tail gas pressure control device according to any one of claims 1-5, characterized in that, A pressure reducing valve (61) is provided between the nitrogen input pipe (6) and the connecting pipe (43). The pressure reducing valve (61) is used to reduce the pressure of the nitrogen input pipe (6) and then input it into the connecting pipe (43).

7. The furnace tube equipment exhaust gas pressure control device according to any one of claims 1-5, characterized in that, The transition chamber (3) is also connected to a drain pipe (34), the inlet of which is located in the lowest area of ​​the transition chamber (3) relative to the horizontal plane, and the drain pipe (34) is used to discharge the condensate in the exhaust gas inlet pipe (1).

8. The furnace tube equipment exhaust gas pressure control device according to claim 2, characterized in that, A mounting bracket (8) is also provided on one side of the piston cavity (4). The linear motor (55) is fixed on the mounting bracket (8). A limit block (81) is fixed on the connecting rod (53). A first limit spring (82) and a second limit spring (83) are fixed on the mounting bracket (8). A limiting space of the limit block (81) is formed between the first limit spring (82) and the second limit spring (83).

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