A pressure detection system

Abstract

The application discloses a pressure detection system suitable for a semiconductor etching device, and the system comprises a main pipeline connected to an exhaust passage of the semiconductor etching device, a pressure gauge, at least two branch pipelines, one end of each of the branch pipelines is connected to the pressure gauge, and the other end of each of the branch pipelines is communicated with the main pipeline, each of the branch pipelines comprises an isolation valve group and a filter, the at least two branch pipelines comprise a first branch pipeline and a second branch pipeline, one end of the first branch pipeline is communicated with the main pipeline, and the other end of the first branch pipeline is connected to the pressure gauge, a first isolation valve group is arranged on the first branch pipeline, and a first filter is arranged on the first branch pipeline, one end of the second branch pipeline is communicated with the main pipeline, and the other end of the second branch pipeline is connected to the pressure gauge, a second isolation valve group is arranged on the second branch pipeline, and a second filter is arranged on the second branch pipeline.

Description

Technical Field

[0001] This application relates to the field of semiconductor manufacturing equipment technology, specifically to a pressure detection system applied to semiconductor etching equipment. Background Technology

[0002] In semiconductor etching processes, process byproducts need to be promptly removed from the reaction chamber. During this process, the pressure in the exhaust pipe needs to be monitored in real time; therefore, a pressure gauge is typically used to continuously monitor the pipe pressure.

[0003] However, prolonged testing can cause the pressure gauge to become clogged with process byproducts, requiring periodic disassembly and replacement or cleaning. Because there is no isolation valve at the front end of the pressure gauge, disassembly requires stopping the vacuum pump and removing the heating element from the pipeline. Figure 2 As shown, after the heating belt is removed, process byproducts inside the pipeline condense at low temperatures upon contact with the atmosphere and accumulate, potentially causing abnormal operation of the vacuum pump. Furthermore, downtime for maintenance reduces equipment uptime and increases maintenance costs.

[0004] Therefore, new solutions are needed to address the aforementioned issues. Utility Model Content

[0005] The purpose of this application is to provide a pressure detection system to solve the problem that in the prior art, pressure gauge maintenance requires shutdown and removal of the heating element, resulting in high maintenance costs and easy damage to the vacuum pump.

[0006] To achieve the above objectives, this application adopts the following technical solution.

[0007] This application provides a pressure detection system suitable for semiconductor etching equipment. The system includes: a main pipeline connected to the exhaust channel of the semiconductor etching equipment; a pressure gauge; at least two branch pipelines, each branch pipeline having one end connected to the pressure gauge and the other end connected to the main pipeline, each branch pipeline including an isolation valve assembly and a filter; the at least two branch pipelines include a first branch pipeline and a second branch pipeline; the first branch pipeline having one end connected to the main pipeline and the other end connected to the pressure gauge; a first isolation valve assembly disposed on the first branch pipeline; a first filter disposed on the first branch pipeline; a second branch pipeline having one end connected to the main pipeline and the other end connected to the pressure gauge; a second isolation valve assembly disposed on the second branch pipeline; and a second filter disposed on the second branch pipeline.

[0008] In some possible implementations, the pressure detection system further includes a purified gas supply line connected to the first branch line and the second branch line, respectively, and the purified gas supply line includes a purified gas supply device.

[0009] In some possible implementations, the first isolation valve group includes a first isolation valve and a second isolation valve, and the second isolation valve group includes a third isolation valve and a fourth isolation valve; the first isolation valve, the first filter, and the second isolation valve are sequentially arranged along the gas flow direction of the first branch pipeline; the third isolation valve, the second filter, and the fourth isolation valve are sequentially arranged along the gas flow direction of the second branch pipeline.

[0010] In some possible implementations, the purified gas supply line further includes a third isolation valve assembly, which includes a fifth isolation valve and a sixth isolation valve, and is connected to the first branch line through the fifth isolation valve; the purified gas supply line is connected to the second branch line through the sixth isolation valve.

[0011] In some possible implementations, the purified gas supply device is connected to an inert gas supply source, preferably nitrogen.

[0012] In some possible implementations, the pressure detection system further includes a first pressure sensor disposed upstream of the first filter.

[0013] In some possible implementations, the pressure detection system further includes a second pressure sensor disposed upstream of the second filter.

[0014] In some possible implementations, the pressure detection system further includes a signal processing device electrically connected to the first pressure sensor, the second pressure sensor, and the pressure gauge, and the signal processing device is provided with a primary alarm signal output terminal, a secondary alarm signal output terminal, and a tertiary alarm signal output terminal.

[0015] In some possible implementations, the first filter and the second filter are removable filters.

[0016] In some possible implementations, a heating belt is provided on the main pipeline.

[0017] This application provides a pressure detection system that utilizes at least two branch lines connected in parallel to the same pressure gauge. Each branch line is equipped with an isolation valve assembly and a filter, enabling alternating operation of the branch lines. When a filter in one branch line requires maintenance, the isolation valve assembly of that branch line can be closed for isolation, and operation can be switched to another branch line. This eliminates the need to shut down the vacuum pump or remove the heating element from the pipeline, thus avoiding the problem of process byproducts condensing and accumulating, which could damage the vacuum pump after the heating element is removed. By sharing a single pressure gauge across multiple branch lines, continuous pressure detection is ensured while reducing equipment costs. Furthermore, purified gas is supplied to each branch line through a purified gas supply line to form a protective gas curtain in front of the pressure gauge's sensor diaphragm, preventing corrosive gases and particulate matter from contacting the pressure gauge and extending its service life. Additionally, by installing pressure sensors upstream of each filter, the pressure difference before and after the filter can be monitored in real time, allowing for timely assessment of filter clogging and maintenance to ensure accurate pressure detection. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram illustrating a scenario where a pressure gauge is used in existing technology.

[0020] Figure 2 This is a schematic diagram of the condensation of byproducts in the exhaust pipeline.

[0021] Figure 3 This is a schematic diagram of a pressure detection system according to an embodiment of this application.

[0022] Figure 4 This is a schematic diagram of a signal processing device according to an embodiment of this application.

[0023] Figure 5 This is a schematic diagram illustrating the nonlinear effects of filter clogging on differential pressure and flow rate. Detailed Implementation

[0024] 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, and 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.

[0025] like Figure 1 As shown, during semiconductor etching, a large number of process byproducts are generated in the reaction chamber 10'. These byproducts include gaseous substances generated during the reaction, unreacted precursor gases, and particulate matter generated during etching. These process byproducts are discharged from the reaction chamber 10' through an exhaust pipe to maintain the process pressure and reaction environment within the chamber. After being discharged from the reaction chamber 10', the process byproducts pass sequentially through a throttle valve 12' (TGV), a turbo pump 41', and an isolation valve 14', before entering the main pipeline 20'. A pressure gauge 30' is installed in the exhaust pipe to monitor the pressure status within the pipeline in real time. The exhaust system typically includes the main pipeline 20', the pressure gauge 30' connected to the main pipeline 20', and a downstream coarse pump 42', where the coarse pump 42' and the turbo pump 41' together form a vacuum pump 40'. The vacuum pump 40' discharges the process byproducts through a multi-stage vacuuming process. A heating strip 50' is provided around the main pipeline 20' to maintain the pipeline temperature.

[0026] The existing technology has the following problems: Because the process byproducts contain corrosive gases and a large amount of particulate matter, long-term use will cause corrosion or damage to the sensor diaphragm of pressure gauge 30' due to contact with particulate matter, affecting the accuracy of pressure detection, and in severe cases, potentially causing the pressure gauge to completely fail. When pressure gauge 30' needs to be disassembled, replaced, or cleaned, it cannot be isolated individually because there is no isolation valve at the front end. Therefore, it is necessary to first shut down vacuum pump 40', causing the entire exhaust pipeline to break the vacuum, and then remove the heating belt 50' from the pipeline before pressure gauge 30' can be removed. This is not only cumbersome, but also causes the pipeline to cool rapidly after the heating belt 50' is removed, breaking the vacuum and allowing atmospheric air to enter the vacuum pipeline. The process byproducts condense at low temperatures, and these condensates 60' may fall into the downstream roughing pump 42', such as... Figure 2 As shown, this caused damage to the coarse pump 42', shortening its service life. Furthermore, the existing maintenance process requires shutting down the equipment, reducing uptime. In addition, frequent pressure gauge clogging and replacement also increase maintenance costs.

[0027] To address the above issues, this application provides a pressure detection system. This system connects at least two branch pipelines in parallel to the same pressure gauge. Each branch pipeline is equipped with an isolation valve assembly and a filter. This allows for the isolation of a branch pipeline from the main pipeline by closing the isolation valve assembly when maintenance is needed, while switching to another branch pipeline continues operation. The main pipeline and vacuum pump can continue operating without requiring a complete shutdown. Since the heating element is located on the main pipeline, maintenance or replacement of components in the branch pipelines can be performed without removing the heating element, avoiding a series of problems caused by removing it. Furthermore, the system supplies purified gas to each branch pipeline through a purified gas supply pipeline, forming an air curtain in front of the pressure gauge sensor diaphragm. This prevents process byproducts from directly contacting the diaphragm and reduces the risk of corrosion or damage to the pressure gauge. Additionally, pressure sensors are installed upstream of each filter. By monitoring pressure changes before and after the filter, the degree of filter clogging can be determined in real time, allowing for appropriate maintenance.

[0028] The pressure detection system of this application will be described in detail below with reference to the accompanying drawings.

[0029] See Figure 3 As shown in one embodiment of this application, a pressure detection system suitable for semiconductor etching equipment is provided. The pressure detection system may include a main pipeline 20, a pressure gauge 30, and at least two branch pipelines, each branch pipeline including an isolation valve assembly and a filter.

[0030] The main pipeline 20 is connected to the exhaust channel of the semiconductor etching equipment to discharge process byproduct gases from the reaction chamber 11. After being discharged from the reaction chamber 11, the process byproducts pass sequentially through a throttle valve 12, a fine pump 71, and an isolation valve 14 before entering the main pipeline 20. The downstream end of the main pipeline 20 is connected to a rough pump 72. The fine pump 71 and the rough pump 72 together form a vacuum pump 70.

[0031] In this embodiment, pressure gauge 30 detects the gas pressure in the main pipeline via a branch pipeline. Pressure gauge 30 can be a diaphragm pressure gauge. If the process byproduct contains a large amount of metal, the diaphragm of the diaphragm pressure gauge can be made of alloy. If the process byproduct contains a small amount of metal, the diaphragm can be made of stainless steel or ceramic. The working principle of pressure gauge 30 is that the gas pressure acts on the sensor diaphragm of pressure gauge 30 to produce deformation, and the deformation is converted into a corresponding pressure value through an electrical signal conversion device.

[0032] In this embodiment, the pressure detection system may include at least two branch lines, one end of each branch line being connected to the pressure gauge 30 and the other end being connected to the main line 20. The parallel connection of multiple branch lines allows each branch line to be isolated and maintained independently, ensuring that at least one branch line is in operation, thus achieving maintenance without system shutdown.

[0033] Those skilled in the art can flexibly adjust the number of branch pipelines according to the testing requirements, and achieve pressure testing schemes with different accuracies by increasing or decreasing the number of parallel branch units (including corresponding isolation valve groups and filters).

[0034] In this embodiment, the at least two branch lines specifically include a first branch line 21 and a second branch line 22. One end of the first branch line 21 is connected to the main line 20, and branches off from the main line 20 to form an independent gas channel. The other end of the first branch line 21 is connected to the pressure gauge 30. The first branch line 21 can be connected to the main line 20 through a pipe interface or a tee connector (not shown in the figure). The first branch line 21 includes a first isolation valve assembly (not shown in the figure) and a first filter 41, and the second branch line 22 includes a second isolation valve assembly (not shown in the figure) and a second filter 42.

[0035] In this embodiment, the first isolation valve assembly is installed on the first branch pipeline 21. For example... Figure 3 As shown, the first isolation valve group includes a first isolation valve 31 and a second isolation valve 32. That is, along the gas flow direction of the first branch pipeline 21, the first isolation valve 31, the first filter 41, and the second isolation valve 32 are sequentially arranged. This places the first filter 41 between the two isolation valves. When maintenance or replacement of the first filter 41 is required, the first isolation valve 31 and the second isolation valve 32 can be closed, completely isolating the pipeline section containing the first filter 41. At this time, maintenance operations can be performed in this pipeline section by breaking the vacuum, while other parts such as the main pipeline 20 and the roughing pump 72 of the vacuum pump 70 can continue to operate under vacuum.

[0036] In this embodiment, the first filter 41 is disposed on the first branch pipeline 21, specifically, downstream of the first isolation valve 31 and upstream of the second isolation valve 32. The first filter 41 is used to filter particulate matter and some gaseous impurities in the process byproducts, preventing these substances from entering the pressure gauge 30. The first filter 41 can be selected from different types according to specific process requirements, such as a particulate filter or a chemical filter. Particulate filters are used to block solid particles through porous media, while chemical filters are used to remove specific corrosive gases through adsorption materials (such as activated carbon).

[0037] Continue reading Figure 3As shown, in this embodiment, one end of the second branch pipe 22 is connected to the main pipe 20, and branches off from the main pipe 20. The other end of the second branch pipe 22 is connected to the pressure gauge 30. The second branch pipe 22 is arranged in parallel with the first branch pipe 21, so that the two branch pipes can work alternately.

[0038] In this embodiment, the second isolation valve assembly is installed on the second branch pipeline 22. For example... Figure 3 As shown, the second isolation valve group includes a third isolation valve 33 and a fourth isolation valve 34. That is, along the gas flow direction of the second branch pipeline 22, the third isolation valve 33, the second filter 42, and the fourth isolation valve 34 are sequentially arranged. Similar to the first isolation valve, by setting up the second isolation valve group, the second filter 42 is located between the two isolation valves. When maintenance or replacement of the second filter 42 is required, the third isolation valve 33 and the fourth isolation valve 34 can be closed to completely isolate the pipeline section where the second filter 42 is located. At this time, maintenance operations can be performed in this pipeline section by breaking the vacuum, while other parts such as the main pipeline 20 and the roughing pump 72 of the vacuum pump 70 continue to operate under vacuum, without affecting the overall operation of the system.

[0039] In this embodiment, the second filter 42 is disposed on the second branch pipe 22, specifically, downstream of the third isolation valve 33 and upstream of the fourth isolation valve 34. The structure and function of the second filter 42 are similar to those of the first filter 41.

[0040] It should be noted that since the ends of the first branch pipe 21 and the second branch pipe 22 are both connected to the same pressure gauge 30, the pressure gauge 30 can be shared when different branch pipes are in operation, without the need to configure a separate pressure gauge for each branch pipe. When it is necessary to maintain or replace the pressure gauge 30, it is only necessary to ensure that the isolation valves at the end of all branch pipes (i.e., the second isolation valve 32 and the fourth isolation valve 34) are in the closed state before the pressure gauge 30 can be disassembled and replaced.

[0041] like Figure 3 The first isolation valve 31, the second isolation valve 32, the third isolation valve 33, and the fourth isolation valve 34 shown can be pneumatic, electric, or manual isolation valves. In this embodiment, pneumatic or electric isolation valves are preferred for integration with the equipment's control system to achieve automated operation.

[0042] In some embodiments, the first isolation valve 31 and the second isolation valve 32 can be different types of isolation valves. For example, the first isolation valve 31 (located upstream of the first filter 41) can be a ball valve, which has a faster opening and closing speed and better sealing performance. The second isolation valve 32 (located downstream of the first filter 41 and upstream of the pressure gauge 30) can be a gate valve, which has lower pressure loss. Similarly, the third isolation valve 33 and the fourth isolation valve 34 can also be different types of isolation valves.

[0043] In some embodiments, the pressure detection system may further include a purified gas supply line 60. The purified gas supply line 60 is connected to a first branch line 21 and a second branch line 22, respectively, for supplying purified gas to each branch line. The purified gas supply line 60 includes a purified gas supply device 61, which controls the flow rate and pressure of the purified gas. The purified gas supply device 61 is connected to an inert gas supply source, which may be a plant gas supply system or an independent gas cylinder. The inert gas is preferably nitrogen, which is chemically stable and does not react with process byproducts.

[0044] In this embodiment, the purified gas supply line 60 may further include a third isolation valve group. The third isolation valve group is used to control the supply of purified gas to the first branch line 21 and the second branch line 22, respectively. Specifically, the third isolation valve group includes a fifth isolation valve 35 and a sixth isolation valve 36. The purified gas supply line 60 is connected to the first branch line 21 via the fifth isolation valve 35 and to the second branch line 22 via the sixth isolation valve 36. That is, the fifth isolation valve 35 controls whether purified gas enters the first branch line 21, and the sixth isolation valve 36 controls whether purified gas enters the second branch line 22.

[0045] Furthermore, after the purified gas enters the first branch pipe 21, it forms an air curtain on the sensor diaphragm of the pressure gauge 30 to prevent corrosive gases and particulate matter from directly contacting the sensor diaphragm of the pressure gauge 30 and to extend the service life of the pressure gauge 30. The flow rate of the purified gas is controlled within a small range, for example, 5 to 20 sccm. It should be noted that if the purified gas flow rate is set too low (for example, below 5 sccm), the flow velocity of the air curtain may not be sufficient to effectively block the spread of process byproducts, and some corrosive gases and particulate matter may still contact the sensor diaphragm of the pressure gauge 30, reducing the protection effect. If the purified gas flow rate is set too high (for example, above 20 sccm), the pressure generated by the purified gas will increase significantly, which will have a greater impact on pressure measurement and will also increase gas consumption costs.

[0046] It should be noted that the "gas curtain" in this article refers to the protective gas barrier formed in front of the sensor diaphragm of the pressure gauge 30. Purified gas (preferably nitrogen) is continuously supplied to the pipeline containing the pressure gauge 30 through the purified gas supply pipeline 60, forming a positive-pressure gas protective layer in front of the sensor diaphragm. This gas protective layer can dilute the concentration of process byproducts and prevent corrosive gases and particulate matter from directly contacting the sensor diaphragm, ensuring that the sensor diaphragm actually contacts the purified protective gas, thereby achieving the purpose of protecting the pressure gauge 30.

[0047] It is important to note that the injection of purified gas will affect the pressure measurement. The purified gas generates additional pressure in the branch line. The total pressure P_total measured by pressure gauge 30 is the sum of the process by-product gas pressure P_process and the purified gas pressure P_purpe, i.e., P_total = P_process + P_purge. To obtain the actual process by-product gas pressure P_process, the following method can be used: During the initial operation of the system, only purified gas is introduced without process by-products. The pressure measured by pressure gauge 30 at this time is P_purge, and this value is set as the zero point of pressure gauge 30. Subsequently, during normal operation, the pressure value displayed by pressure gauge 30 is the pressure change relative to this zero point, which is P_process.

[0048] In some embodiments, a linkage control is provided between the fifth isolation valve 35, the first isolation valve group, the sixth isolation valve 36, and the second isolation valve group to realize the opening and closing of each isolation valve group. Specifically, the fifth isolation valve 35 and the first isolation valve group open and close synchronously, and the sixth isolation valve 36 and the second isolation valve group open and close synchronously, with one group of the first isolation valve group and the second isolation valve group being normally open and the other group being normally closed. To achieve the above-mentioned synchronous opening and closing and normally open and normally closed states, a conventional control system in the art (such as a programmable logic controller (PLC) or a dedicated control module) can be used to realize the linkage control through electrical or pneumatic control, which will not be elaborated here.

[0049] In this embodiment, the pressure detection system may further include a first pressure sensor 51 and a second pressure sensor 52. The first pressure sensor 51 is disposed upstream of the first filter 41, i.e., in the pipeline between the first isolation valve 31 and the first filter 41. The first pressure sensor 51 is used to detect the pressure at the air inlet of the first filter 41. The second pressure sensor 52 is disposed upstream of the second filter 42, i.e., in the pipeline between the third isolation valve 33 and the second filter 42. The second pressure sensor 52 is used to detect the pressure at the air inlet of the second filter 42.

[0050] It is worth noting that the pressure difference ΔP1 between the front and rear ends of the first filter 41 can be obtained by comparing the pressure detected by the first pressure sensor 51 with the pressure detected by the pressure gauge 30. Similarly, the pressure difference ΔP2 between the front and rear ends of the second filter can be obtained by comparing the pressure detected by the second pressure sensor 52 with the pressure detected by the pressure gauge 30. When the first filter 41 or the second filter 42 is in a brand-new, clean state, its resistance to airflow is small, and the pressure difference is the initial pressure difference ΔP0. As the filter usage time increases, particulate matter from process byproducts gradually deposits on the filter element surface or in the internal pores, causing the filter's conductance (i.e., the ratio of airflow rate to pressure difference per unit time) to decrease, and the corresponding pressure difference to increase. In a vacuum system, the decrease in conductance caused by filter blockage and the increase in pressure difference have the following relationship: ΔP / ΔP0 = C0 / C = 1 / (1 - degree of blockage), where ΔP is the current pressure difference, ΔP0 is the initial pressure difference (i.e., the pressure difference when the filter is clean), C is the current conductance, and C0 is the initial conductance. According to the above relationship, as the degree of filter clogging gradually increases, the pressure difference will increase non-linearly, such as... Figure 5 As shown.

[0051] like Figure 4As shown, in some embodiments, the pressure detection system further includes a signal processing device 90. The signal processing device 90 is electrically connected to the first pressure sensor 51, the second pressure sensor 52, and the pressure gauge 30, and is used to receive the pressure signals output by the first pressure sensor 51, the second pressure sensor 52, and the pressure gauge 30, calculate the pressure difference, and output a corresponding alarm signal based on the comparison result of the pressure difference with a preset threshold. The signal processing device 90 may include a digital-to-analog converter circuit 91, a microcontroller unit 92 (MCU), and a storage module 93. The analog voltage or current signals output by the first pressure sensor 51, the second pressure sensor 52, and the pressure gauge 30 are converted into digital signals by the digital-to-analog converter circuit 91 and transmitted to the microcontroller unit 92 for processing. The storage module 93 pre-stores the initial pressure difference ΔP0 and alarm thresholds at various levels. The microcontroller unit 92 obtains the initial pressure difference ΔP0 from the storage module 93, compares the real-time measured pressure difference ΔP with the initial pressure difference ΔP0, calculates the ratio of ΔP / ΔP0, and obtains the alarm thresholds for each level from the storage module 93, comparing the ratio of ΔP / ΔP0 with each level of alarm threshold. The signal processing device 90 is equipped with a first-level alarm signal output terminal 941, a second-level alarm signal output terminal 942, and a third-level alarm signal output terminal 943. It should be noted that these three output terminals correspond to different levels of clogging. For example, when ΔP / ΔP0 reaches 2, it indicates that the filter clogging degree is approximately 50%, the conductance has decreased to 50% of the initial value, and the system's pumping efficiency begins to decline significantly. At this time, the signal processing device 90 outputs a warning signal through the first-level alarm signal output terminal 941, prompting the operator to prepare to replace the filter, which can be scheduled for the next maintenance window. When ΔP / ΔP0 reaches 3, it indicates that the filter is approximately 67% clogged, the conductance has decreased to 33% of its initial value, and the pressure reading begins to distort. At this point, the signal processing device 90 outputs an alarm signal through the secondary alarm signal output terminal 942, prompting the operator to replace the filter within one week. When ΔP / ΔP0 reaches 4 or 5, it indicates that the filter is approximately 75% to 80% clogged, the conductance has decreased to 20% of its initial value, the airflow pattern has changed, pressure control has failed, and the process results are unpredictable. At this point, the signal processing device 90 outputs a critical alarm signal through the tertiary alarm signal output terminal 943, prompting the operator to immediately stop the machine and replace the filter. The specific values ​​of the above alarm thresholds can be adjusted according to actual process requirements. In practical applications, the signal processing device 90 can simultaneously monitor the operating status of the first branch pipeline 21 and the second branch pipeline 22. The signal processing device 90 calculates the pressure difference between the front and rear ends of the corresponding filter based on the currently operating branch pipeline and outputs a corresponding alarm signal based on the pressure difference value.For example, when the first branch line 21 is in operation, the signal processing device 90 monitors the pressure difference between the first pressure sensor 51 and the pressure gauge 30; when switching to the second branch line 22, the signal processing device 90 monitors the pressure difference between the second pressure sensor 52 and the pressure gauge 30.

[0052] In some embodiments, both the first filter 41 and the second filter 42 are removable filters. Each filter may include a filter housing and a replaceable filter element (not shown in the figure). Operators can easily remove and replace the filter element by simply removing the filter housing fasteners (such as bolts or clips) (not shown in the figure). Furthermore, due to the presence of the first and second isolation valve assemblies, filter maintenance can be performed after the isolation valves are closed, without needing to remove the heating element 80 on the main pipeline 20. This avoids the problems of process byproduct condensation and damage to the roughing pump 72 caused by removing the heating element in the prior art.

[0053] In some embodiments, the first filter 41 and the second filter 42 may employ filter elements of different types or pore sizes to meet different process requirements. For example, for processes with a large amount of particulate matter, a combination of a filter with a larger pore size and a filter with a smaller pore size can be used; for processes with highly corrosive gases, a chemical adsorption filter can be added after the particulate filter.

[0054] In some embodiments, a heating band 80 is provided on the main pipeline 20. The heating band 80 is arranged around the main pipeline 20 and maintains the pipeline temperature within a preset range by electric heating to prevent process byproducts from condensing on the inner wall of the pipeline. The heating band can be a heating plate or a heating cable. In other embodiments, the heating band 80 is not only provided on the main pipeline 20, but can also extend to a portion of the first branch pipeline 21 and / or the second branch pipeline 22. For example, the heating band 80 can extend from the main pipeline 20 to the isolation valve location of each branch pipeline, covering the section of pipeline between the main pipeline 20 and the corresponding isolation valve to ensure that process byproducts do not condense in that section of pipeline. However, the heating band 80 does not cover the location of the filter and pressure gauge 30 to facilitate the disassembly and replacement of these components.

[0055] The working mode of the pressure detection system of this application will be further described below.

[0056] Under normal operating conditions, one of the first branch pipeline 21 and the second branch pipeline 22 is in operation, while the other is in standby mode. For example, initially, the first branch pipeline 21 is in operation. At this time, the fifth isolation valve 35 is normally open, as are the first and second isolation valves 31 and 32. Purified gas enters the first branch pipeline 21 through the fifth isolation valve 35, while process byproduct gas is diverted from the main pipeline 20 into the first branch pipeline 21, passing sequentially through the first isolation valve 31, the first filter 41, and the second isolation valve 32 before reaching the pressure gauge 30 for pressure detection. The purified gas forms a protective gas curtain in front of the sensor diaphragm of the pressure gauge 30, preventing corrosive gases and particulate matter from directly contacting the sensor diaphragm. Simultaneously, the third and fourth isolation valves 34 are normally closed, as is the sixth isolation valve 36, preventing process byproduct gas from entering the second branch pipeline 22. The second branch pipeline 22 is in standby mode, maintained under vacuum or filled with inert gas for protection, and is ready to be switched over and used at any time. When the first pressure sensor 51 detects that the pressure difference between the front and rear ends of the first filter 41 exceeds a preset threshold, it indicates that the first filter 41 is about to become clogged or has already become clogged and needs to be replaced and maintained. At this time, the pressure detection system can switch to the second branch pipeline 22. The specific switching process is as follows: First, the signal processing device 90 of the pressure detection system issues an alarm signal, and the operator confirms that the branch pipeline needs to be switched. Then, the first isolation valve 31, the second isolation valve 32, and the fifth isolation valve 35 are closed, isolating the first branch pipeline 21 from the main pipeline 20. That is, the fifth isolation valve 35 closes synchronously with the first isolation valve group, the purified gas stops being supplied to the first branch pipeline 21, and the process by-product gas no longer enters the first branch pipeline 21. Next, the third isolation valve 33, the fourth isolation valve 34, and the sixth isolation valve 36 are opened, allowing the second branch pipeline 22 to enter the working state. In other words, the sixth isolation valve 36 opens synchronously with the second isolation valve group, and the process by-product gas begins to flow into the second branch pipeline 22, passing sequentially through the third isolation valve 33, the second filter 42, and the fourth isolation valve 34 to reach the pressure gauge 30 for pressure detection. Simultaneously, the purified gas supply pipeline 60 supplies purified gas to the second branch pipeline 22, forming a protective gas curtain in front of the sensor diaphragm of the pressure gauge 30. At this time, the process by-product gas in the main pipeline 20 continues to be discharged to the roughing pump 72 through the main pipeline 20, and the system does not need to be shut down; the equipment can continue to operate. After the first branch pipeline 21 is completely isolated, the operator can disassemble and replace the first filter 41. Throughout the maintenance process, the second branch pipeline 22 continues to operate, and the pressure detection function is unaffected. After the maintenance of the first branch pipeline 21 is completed, the second branch pipeline 22 can continue to operate, and the first branch pipeline 21 can be used as a backup pipeline; or the system can be switched back to the first branch pipeline 21, and the second branch pipeline 22 can be used as a backup pipeline.It should be noted that the maintenance of pressure gauge 30 is relatively simple. Since pressure gauge 30 is located downstream of the second isolation valve 32 and the fourth isolation valve 34, the two branch lines share the same pressure gauge 30. When pressure gauge 30 needs to be replaced, it is only necessary to ensure that both the second isolation valve 32 and the fourth isolation valve 34 are closed before disassembling and replacing it; there is no need to switch branch lines. During the maintenance of pressure gauge 30, the entire system needs to temporarily stop pressure monitoring, but the main pipeline 20 and vacuum pump 70 can continue to operate without affecting the discharge of process byproducts.

[0057] In some embodiments, the pressure detection system may include two or more branch lines. For example, in addition to the first branch line 21 and the second branch line 22, a third branch line, a fourth branch line, etc., may also be provided. The structure of each branch line is similar to that of the first branch line 21 or the second branch line 22, and one end of each branch line is connected to the main line 20, and the other end is connected to the same pressure gauge 30. The purified gas supply line 60 can be connected to multiple branch lines simultaneously through distribution lines. In this way, at least one branch line is in operation for pressure detection, while other branch lines can be in standby or maintenance status. When the filter of a branch line needs to be replaced, the system can switch to another branch line to continue operation, thereby achieving uninterrupted pressure detection.

[0058] The pressure detection system in this embodiment connects at least two branch lines in parallel to the same pressure gauge. Each branch line is equipped with an isolation valve assembly and a filter, enabling isolated maintenance of the filters and related components without shutdown or disassembly of the heating element 80. This avoids the problems of process byproduct condensation and damage to the roughing pump 72 caused by disassembling the heating element 80. Furthermore, the purified gas supplied by the purified gas supply line 60 forms a protective air curtain in front of the sensor diaphragm of the pressure gauge 30, preventing process byproducts from directly contacting the pressure gauge 30 and extending its service life. In addition, by installing pressure sensors upstream of each filter and combining them with the signal processing device 90, real-time monitoring and graded alarms of filter clogging levels are achieved. Moreover, the use of multiple parallel branch lines further improves the reliability of the system, enabling uninterrupted pressure detection.

[0059] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The features, structures, or characteristics described above can be combined in any suitable manner in one or more embodiments.

[0060] It is understood that those skilled in the art, guided by the above embodiments, can combine various implementation methods in the above embodiments to obtain technical solutions with multiple implementation methods. The above descriptions are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A pressure detection system, suitable for semiconductor etching equipment, characterized in that, include: The main pipeline connects to the exhaust channel of the semiconductor etching equipment; pressure gauge; At least two branch lines, one end of each branch line is connected to the pressure gauge and the other end is connected to the main line, and each branch line includes an isolation valve assembly and a filter; The at least two branch pipes include a first branch pipe and a second branch pipe; The first branch pipeline has one end connected to the main pipeline and the other end connected to a pressure gauge. The first isolation valve assembly is installed on the first branch pipeline; The first filter is installed on the first branch pipeline; The second branch pipeline has one end connected to the main pipeline and the other end connected to the pressure gauge. The second isolation valve assembly is installed on the second branch pipeline; as well as The second filter is installed on the second branch pipeline.

2. The pressure detection system as described in claim 1, characterized in that, It also includes a purified gas supply pipeline, which is connected to the first branch pipeline and the second branch pipeline respectively, and the purified gas supply pipeline includes a purified gas supply device.

3. The pressure detection system as described in claim 1, characterized in that, The first isolation valve group includes a first isolation valve and a second isolation valve, and the second isolation valve group includes a third isolation valve and a fourth isolation valve; Along the gas flow direction of the first branch pipeline, the first isolation valve, the first filter, and the second isolation valve are sequentially installed; Along the gas flow direction of the second branch pipeline, the third isolation valve, the second filter, and the fourth isolation valve are sequentially installed.

4. The pressure detection system as described in claim 2, characterized in that, The purified gas supply pipeline also includes a third isolation valve group, which includes a fifth isolation valve and a sixth isolation valve. The fifth isolation valve is connected to the first branch pipeline. The purified gas supply pipeline is connected to the second branch pipeline through the sixth isolation valve.

5. The pressure detection system as described in claim 2, characterized in that, The purified gas supply device is connected to an inert gas supply source, and the inert gas is nitrogen.

6. The pressure detection system as described in claim 1, characterized in that, Also includes: The first pressure sensor is located upstream of the first filter.

7. The pressure detection system as described in claim 6, characterized in that, Also includes: The second pressure sensor is located upstream of the second filter.

8. The pressure detection system as described in claim 7, characterized in that, It also includes a signal processing device, which is electrically connected to the first pressure sensor, the second pressure sensor and the pressure gauge. The signal processing device is provided with a first-level alarm signal output terminal, a second-level alarm signal output terminal and a third-level alarm signal output terminal.

9. The pressure detection system as described in claim 1, characterized in that, The first filter and the second filter are removable filters.

10. The pressure detection system as described in claim 1, characterized in that, A heating belt is installed on the main pipeline.

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