Method and system for testing performance of adsorption filler in negative pressure steel cylinder

Abstract

The invention discloses a performance testing method and system for adsorption filler in a negative pressure steel cylinder, and belongs to the technical field of semiconductor production and manufacturing. During testing, the adsorption filler is filled into the negative pressure steel cylinder, the negative pressure steel cylinder is vacuumized to a target negative pressure value P0, and the initial weight M0 of the negative pressure steel cylinder at the moment is recorded. The negative pressure steel cylinder is filled with the test gas at a set flow rate, and the air pressure in the negative pressure steel cylinder is detected in real time, so that the negative pressure steel cylinder is in a negative pressure state until an adsorption saturation state is reached. And in the adsorption saturation state, the air pressure in the negative-pressure steel cylinder is stabilized at a set air pressure value P1 within 12 hours. And after the adsorption saturation state is reached, stopping filling the test gas, and obtaining the weight M1 of the filled negative pressure steel cylinder. The adsorption capacity of the adsorption filler at the set air pressure value P1 is M1-M0. According to the test method, the adsorption capacity of the adsorption filler in the actual filling process of the negative pressure steel cylinder can be reflected more accurately.

Description

Technical Field

[0001] The present application relates to the field of semiconductor production and manufacturing technology, and in particular to a performance testing method and a testing system for an adsorption filler in a negative pressure cylinder. Background Art

[0002] The manufacturing process of semiconductors requires the use of some toxic doping gases (such as A s For example, H3, PH3, and BF3, dopant gases are typically stored in negative pressure cylinders with built-in adsorbents (i.e., adsorbents). The performance of the adsorbents within negative pressure cylinders directly affects filling efficiency and safe filling volume. Therefore, performance testing of the adsorbents within negative pressure cylinders is essential. Summary of the Invention

[0003] The present application provides a performance testing method and a testing system for an adsorption filler in a negative pressure steel cylinder, so as to test the performance of the adsorption filler in the negative pressure steel cylinder.

[0004] This application is implemented as follows: In a first aspect, an example of the present application provides a method for testing the performance of an adsorption filler in a negative pressure cylinder, comprising: S1. Initial state calibration: Place the adsorption filler into the negative pressure cylinder, evacuate the negative pressure cylinder to the target negative pressure value P0, and record the initial weight M0 of the negative pressure cylinder at this time.

[0005] S2. Test Gas Injection: Fill the negative pressure cylinder with test gas at a set flow rate and monitor the pressure in the cylinder in real time. Maintain the negative pressure in the cylinder until it reaches adsorption saturation. Adsorption saturation means that the pressure in the cylinder remains stable at the set pressure value P1 within 12 hours.

[0006] S3. Determine adsorption capacity: After reaching adsorption saturation, stop adding test gas and obtain the filled weight M1 of the negative pressure cylinder. The adsorption capacity of the adsorption filler at the set pressure value P1 is M1-M0.

[0007] In the above implementation process, a negative pressure cylinder containing an adsorbent filler is evacuated to a target negative pressure value. This removes impurities within the cylinder, thereby reducing the impact of these impurities on the performance of the adsorbent filler. A test gas is then added to the cylinder. The filling process progresses through three stages: pressure rise, pressure drop, and pressure stabilization. The pressure within the cylinder is monitored in real time. If the pressure is too high, the test gas supply is suspended and refilled after the pressure drops, maintaining the negative pressure state throughout the filling process. If the pressure within the cylinder remains at the set pressure value P1 for 12 hours, the adsorption capacity of the adsorbent filler at the set pressure has reached saturation. Test gas supply is then stopped, and the cylinder's post-fill weight (M1) is measured. The initial weight (M0) of the cylinder, when evacuated to the target negative pressure, is subtracted from the post-fill weight (M1) to obtain the adsorption capacity of the adsorbent filler for the test gas at the set pressure value. Placing the adsorption filler in a negative pressure cylinder to test the performance of the adsorption filler and simulate the actual filling process of the adsorption filler in the negative pressure cylinder can more accurately reflect the adsorption capacity of the adsorption filler in the actual adsorption process and improve the accuracy of the test results.

[0008] In conjunction with the first aspect, in an embodiment of the present application, in step S2, the flow rate is set to 0.1-1 L / min. The adsorption time from the start of filling the negative pressure cylinder with the test gas to the adsorption saturation state is monitored, and the adsorption time represents the adsorption rate of the adsorption filler.

[0009] In the above implementation process, by monitoring the adsorption time from the beginning of filling the test gas into the negative pressure cylinder to reaching the adsorption saturation state, it can be reflected how fast the adsorption filler adsorbs to the set pressure value, and thus reflect the adsorption rate of the adsorption filler.

[0010] In combination with the first aspect, in an embodiment of the present application, in step S2, the temperature of the negative pressure cylinder is monitored in real time, and when the temperature is higher than the set temperature, the filling of the test gas is suspended.

[0011] Optionally, the material of the adsorption filler is an asphalt-based material, the test gas contains phosphine, and the set temperature is 60~80℃.

[0012] During the test gas filling process, the temperature inside the negative pressure cylinder will rise as the gas is added. If the temperature inside the negative pressure cylinder is too high, it will damage the performance of the adsorption filler. For example, the adsorption filler is usually loaded with gas substances. When the temperature inside the negative pressure cylinder rises, some of the loads of the adsorption filler will react, affecting the performance of the adsorption filler. In addition, excessively high temperatures will damage the internal pore structure of the adsorption filler and affect the performance of the adsorption filler itself. In the above implementation process, the temperature inside the negative pressure cylinder is monitored in real time. When the temperature inside the negative pressure cylinder is too high, the test gas is stopped. After the temperature inside the negative pressure cylinder drops, the test gas is continued to be filled. This can reduce the impact of damage to the adsorption filler during the adsorption process on the test adsorption capacity data. For example, when the adsorption filler is an asphalt-based material, the set temperature of the adsorption cylinder can be set to 60~80℃. If the asphalt-based adsorption filler is exposed to a high temperature of 60~80℃ for a long time, the internal pore structure will be damaged and the performance will be affected.

[0013] In combination with the first aspect, in an embodiment of the present application, the test gas includes a carrier gas and a test gas; in step S2, when the test gas is filled into the negative pressure cylinder according to the set flow rate, the concentration of the test gas in the test gas decreases gradually over time.

[0014] Optionally, set the flow rate to 0.1~1L / min.

[0015] Optionally, the air pressure value P1 is set to 700~750torr.

[0016] In the above implementation, when the negative pressure cylinder is filled with test gas, and the filling flow rate remains constant, the space available for the test gas in the negative pressure cylinder is initially large. Filling the negative pressure cylinder with test gas at a high concentration allows the test gas to be quickly adsorbed to the adsorption filler. As the filling process progresses, the remaining space available in the negative pressure cylinder gradually decreases, and the gas adsorption rate slows. Therefore, filling the negative pressure cylinder with test gas at a low concentration prevents the pressure in the negative pressure cylinder from suddenly rising to or exceeding normal pressure, thereby reducing the chance of overfilling the negative pressure cylinder.

[0017] During the test gas filling process, if the pressure in the negative pressure cylinder is maintained at 700-750 Torr for 12 hours, it indicates that adsorption saturation is achieved at a pressure of 700-750 Torr. Since normal pressure is approximately 760 Torr, in order to maintain a negative pressure state, if the pressure in the negative pressure cylinder is maintained at 700-750 Torr for 12 hours, it can be said that the maximum adsorption capacity of the adsorption filler has been reached.

[0018] In combination with the first aspect, in an embodiment of the present application, the testing method further includes S4 located after step S3, and S4 is a desorption step: extracting the test gas adsorbed in the negative pressure cylinder, monitoring the air pressure and weight of the negative pressure cylinder in real time, and drawing a curve of weight change with air pressure.

[0019] In the above implementation process, after filling is completed, the test gas adsorbed by the adsorption filler in the negative pressure cylinder can be desorbed, the test gas in the negative pressure cylinder can be extracted, and the air pressure and weight of the negative pressure cylinder can be recorded in real time. The air pressure value and weight of the negative pressure cylinder are matched to each other, which can reflect the desorption amount at each air pressure value and reflect the desorption efficiency. In addition, the user does not need to weigh the negative pressure cylinder in later use, and can roughly determine the remaining test gas in the negative pressure cylinder based on the air pressure in the negative pressure cylinder.

[0020] In conjunction with the first aspect, in an embodiment of the present application, the testing method further includes S5, a cycle life test: repeating steps S1, S2, S3, and S4, recording the adsorption capacity in step S3 for each cycle. When the adsorption capacity decreases by 5% compared to the initial adsorption capacity during the first adsorption, the corresponding number of cycles represents the cycle life of the adsorption filler.

[0021] Optionally, in step S1, the target negative pressure value is 0.1-1 mbar.

[0022] As the number of adsorption-desorption cycles of the adsorbent increases, the performance of the adsorbent decreases. In the above implementation process, steps S1, S2, S3, and S4 are repeated, and the adsorption capacity in step S3 is recorded for each cycle. The adsorption capacity during each cycle is compared with the initial adsorption capacity. When the adsorption capacity during the cycle decreases by 5% compared to the initial adsorption capacity, it indicates that the performance of the adsorbent has decreased, and it can be determined that the adsorption life of the adsorbent has been reached.

[0023] In step S1, before filling the test gas, the negative pressure cylinder is evacuated to 0.1~1mbar. It can be basically determined that the residual gas in the negative pressure cylinder is extracted, which can reduce the impact of the residual gas in the negative pressure cylinder on the adsorption filler performance test.

[0024] In combination with the first aspect, in an embodiment of the present application, in step S4, the surface quality of the adsorption filler in the negative pressure cylinder is observed after each cycle. If the number of cycles corresponding to the pulverization of the adsorption filler is less than the number of cycles corresponding to when the adsorption capacity decreases by 5% compared with the initial adsorption capacity at the first adsorption, then the number of cycles corresponding to the pulverization of the adsorption filler represents the cycle life of the adsorption filler.

[0025] In the above implementation process, when testing the cycle service life, the surface quality of the adsorption filler is observed after each cycle. Before the adsorption capacity decreases by 5%, if the adsorption filler is observed to be pulverized, it means that the service life of the adsorption filler is reduced. It can be considered that the number of cycles when the adsorption filler is pulverized represents the effective service life of the adsorption filler.

[0026] In a second aspect, examples of the present application provide a testing system for implementing the testing method provided in the first aspect, comprising a negative pressure cylinder, a vacuum pump, and a test gas delivery device. The negative pressure cylinder is configured to be placed on an electronic scale and is provided with a pressure sensor for detecting the air pressure within the negative pressure cylinder. The vacuum pump is selectively connected to the internal chamber of the negative pressure cylinder to extract the gas within the negative pressure cylinder. The test gas delivery device is selectively connected to the internal chamber of the negative pressure cylinder to deliver the test gas to the negative pressure cylinder.

[0027] When using the aforementioned testing system to test the performance of an adsorbent filler, the filler to be tested is placed in a negative pressure cylinder. A vacuum pump is then used to evacuate the cylinder to the target negative pressure. The cylinder is then weighed using an electronic scale, and the initial weight, M0, of the cylinder is recorded. A test gas delivery device is then used to fill the cylinder at a set flow rate, and the pressure within the cylinder is monitored in real time using a pressure sensor. When the pressure within the cylinder approaches 760 Torr (approximately equal to atmospheric pressure), the test gas delivery is suspended, maintaining a constant negative pressure in the cylinder. Once the pressure within the cylinder stabilizes at the set pressure, P1, within 12 hours, the test gas delivery is stopped. The filled cylinder is then weighed again using an electronic scale, M1. M1 minus M0 represents the effective adsorption capacity of the filler at the set pressure, P1. The use of the above-mentioned testing system to test the adsorption capacity of the adsorption filler can simulate the actual filling process of the adsorption filler in the negative pressure cylinder, and can more accurately reflect the adsorption capacity of the adsorption filler in the actual adsorption process.

[0028] In conjunction with the second aspect, in an embodiment of the present application, the vacuum pump is connected to the internal chamber of the negative pressure cylinder via a first pipeline, the first pipeline being provided with a first diaphragm valve. The test gas delivery device is connected to the internal chamber of the negative pressure cylinder via a second pipeline, the second pipeline being provided with a second diaphragm valve.

[0029] Optionally, the test system further comprises a replacement gas conveyor connected to the second pipeline via a third pipeline. The third pipeline is provided with a third diaphragm valve.

[0030] Optionally, the second pipeline is further provided with a flow meter, a one-way valve and the first pneumatic diaphragm valve in sequence at the rear end of the second diaphragm valve. The pressure sensor is provided in the second pipeline between the first pneumatic diaphragm valve and the negative pressure cylinder.

[0031] Optionally, the test system further includes an exhaust gas processor, the outlet of the vacuum pump is connected to the exhaust gas processor via a fourth pipeline, and the fourth pipeline is provided with a fourth diaphragm valve.

[0032] In combination with the second aspect, in an embodiment of the present application, the negative pressure cylinder is further provided with a temperature sensor for measuring the temperature inside the negative pressure cylinder.

[0033] Optionally, the test system further includes a temperature controller, which is used to adjust the temperature of the negative pressure cylinder.

[0034] In the aforementioned implementation process, when testing the performance of the adsorbent filler using the aforementioned test system, the adsorbent filler is placed into a negative pressure steel cylinder, the cylinder valve of the negative pressure steel cylinder is closed, and all diaphragm valves and pneumatic diaphragm valves are closed. The first and fourth diaphragm valves are then opened, the vacuum pump is activated, and the pressure sensor is monitored. When the pressure sensor displays the target negative pressure value P0, the vacuum pump and the first diaphragm valve are closed to determine whether the pipeline between the first and second pneumatic diaphragm valves meets the negative pressure requirement. If qualified, the first diaphragm valve is opened again, the cylinder valve of the negative pressure steel cylinder is opened, the vacuum pump is activated, and the pressure within the negative pressure steel cylinder is determined by observing the pressure sensor. When the pressure sensor again displays the target negative pressure value P0, the electronic scale is activated to weigh the negative pressure steel cylinder to obtain the initial weight M0 of the negative pressure steel cylinder. The first diaphragm valve and vacuum pump are then closed, the second diaphragm valve is opened, the flowmeter is set to the set flow rate, the first pneumatic diaphragm valve is opened, and the test gas is then delivered to the negative pressure steel cylinder. Observe the pressure sensor. When the pressure approaches positive pressure, for example, greater than 700~750torr, control the first pneumatic diaphragm valve to close and suspend inflation. After the air pressure in the negative pressure cylinder drops, open the first pneumatic diaphragm valve and continue inflation. At the same time, monitor the temperature in the negative pressure cylinder through the temperature sensor. When the temperature is too high, close the first pneumatic diaphragm valve, suspend inflation, and use the temperature to adjust the temperature in the negative pressure cylinder. After the temperature in the negative pressure cylinder drops, open the first pneumatic diaphragm valve. When the air pressure value displayed by the pressure sensor stabilizes at the set air pressure value P1 within 12 hours, it means that the adsorption capacity of the adsorption filler at this air pressure value has reached saturation. Then use an electronic scale to weigh the negative pressure cylinder after adsorption again to obtain the weight after filling M1. The adsorption capacity of the adsorption filler at the set air pressure value P0 can be obtained as M1-M0. Then, when the negative pressure cylinder needs to be removed, the second diaphragm valve and the cylinder valve of the negative pressure cylinder can be closed, the first diaphragm valve and the vacuum pump can be opened, the third diaphragm valve can be opened, nitrogen can be introduced, and the pipeline can be circulated and purged. The exhaust gas extracted by the vacuum pump can be sent to the exhaust gas treatment unit through the fourth pipeline for exhaust gas treatment. After the purge is completed, the third diaphragm valve, the first pneumatic diaphragm valve, the first diaphragm valve, and the fourth diaphragm valve can be closed. The outlet of the vacuum pump can be connected to the exhaust gas processor through the fourth pipeline. The gas extracted by the vacuum pump will be immersed in the exhaust gas processor for exhaust gas treatment, which can improve environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art.

[0036] Figure 1 A connection diagram of a test system provided in an embodiment of the present application is shown; Figure 2 This is a curve showing the change of desorption weight with air pressure provided in Example 1 of the present application.

[0037] Icon: 100 - Test system; 1 - Negative pressure cylinder; 2 - Electronic scale; 3 - Vacuum pump; 4 - Test gas delivery device; 5 - Pressure sensor; 6 - First pipeline; 7 - First diaphragm valve; 8 - Second pipeline; 9 - Second diaphragm valve; 10 - Displacement gas delivery device; 11 - Third pipeline; 12 - Third diaphragm valve; 13 - Flow meter; 14 - Check valve; 15 - First pneumatic diaphragm valve; 16 - Controller; 17 - Exhaust gas processor; 18 - Fourth pipeline; 19 - Fourth diaphragm valve; 20 - Temperature sensor; 21 - Temperature controller; 22 - Gas detector. DETAILED DESCRIPTION

[0038] The embodiments of the present application will be described in detail below with reference to the examples, but it will be understood by those skilled in the art that the following examples are merely illustrative of the present application and should not be considered as limiting the scope of the present application. In the examples, if specific conditions are not specified, the conditions are carried out according to conventional conditions or manufacturer recommendations. The reagents or instruments used are not specified by the manufacturer and are conventional products that can be purchased commercially.

[0039] The semiconductor manufacturing process requires the use of toxic dopant gases (such as AsH3, PH3, and BF3). These gases are typically stored in negative pressure cylinders with built-in adsorbents (i.e., adsorbents). The performance of the adsorbents within the negative pressure cylinders directly impacts the filling efficiency and safe volume. Therefore, performance testing of the adsorbents within negative pressure cylinders is essential.

[0040] Conventional testing methods usually reflect the performance of adsorption fillers by testing their pore area and surface quality. This test is usually at the material level and cannot reflect the true and effective performance of the adsorption filler during the actual filling process of the negative pressure cylinder, nor can the test data be used to guide the adjustment of filling parameters during industrial production.

[0041] Based on this, an embodiment of the present application provides a performance testing method for adsorption fillers in negative pressure cylinders to test the performance of adsorption fillers and to guide the adjustment of filling parameters during the industrial production of negative pressure cylinders.

[0042] The performance testing method of the adsorption filler in the negative pressure cylinder provided in the embodiment of the present application includes: S1. Initial state calibration: Place the adsorption filler into the negative pressure cylinder, evacuate the negative pressure cylinder to the target negative pressure value P0, and record the initial weight M0 of the negative pressure cylinder at this time.

[0043] S2. Test gas injection: Fill the negative pressure cylinder with test gas at a set flow rate and monitor the pressure in the cylinder in real time to maintain a constant negative pressure state until adsorption saturation is reached. Adsorption saturation means that the pressure in the negative pressure cylinder remains stable at the set pressure value P1 within 12 hours.

[0044] S3. Determine adsorption capacity: After reaching adsorption saturation, stop adding test gas and obtain the filled weight M1 of the negative pressure cylinder. The adsorption capacity of the adsorption filler at the set pressure value P1 is M1-M0.

[0045] In step S1, the negative pressure cylinder filled with filler is evacuated to a target negative pressure value, and impurity gas in the negative pressure cylinder is extracted to reduce the influence of the impurity gas in the negative pressure cylinder on the adsorption performance of the filler.

[0046] In some embodiments, the target negative pressure value P0 may be 0.1-1 mbar. Evacuating the negative pressure cylinder to 0.1-1 mbar can almost eliminate impurity gases in the negative pressure cylinder and gases adsorbed by the adsorption filler, which can further improve the test accuracy.

[0047] As an example, in step S1 , the adsorption filler loaded into the negative pressure cylinder may be evacuated to one or any one of the ranges of 0.1 mbar, 0.5 mbar or 1 mbar.

[0048] In step S1 , the present application does not limit the type of the adsorption filler. In some embodiments, the adsorption filler may be an adsorption filler of an asphalt-based material, and the test gas may be phosphine gas.

[0049] In some embodiments, the adsorption filler may be a carbon block adsorption filler, which may be used to adsorb phosphine.

[0050] Furthermore, in step S1, the present application does not limit the weight of the adsorption filler loaded into the negative pressure cylinder. In some embodiments, 100g, 200g or 300g of adsorption filler can be loaded into the negative pressure cylinder to obtain adsorption capacity of different adsorption filler filling amounts.

[0051] In step S1, after the negative pressure cylinder is evacuated to the target negative pressure value P0, the weight of the negative pressure cylinder at this time is weighed and recorded as the initial weight M0. Recording the initial weight of the negative pressure cylinder before filling with the test gas facilitates the subsequent calculation of the adsorption capacity of the adsorbent material by using the difference between the filled weight of the negative pressure cylinder after being filled to saturation with the test gas and the initial weight.

[0052] In step S2, the test gas is filled into the negative pressure cylinder at a set flow rate. During the filling process, as the filling progresses, the adsorption rate of the adsorption filler will slow down. In the early stage, since the space in the negative pressure cylinder that can accommodate the test gas is large, the test gas filled into the negative pressure cylinder will be quickly adsorbed by the adsorption filler. If a curve of the change of the air pressure in the negative pressure cylinder over time is plotted during the filling process, for example, in the early stage, 5g of phosphine is filled into a negative pressure cylinder filled with carbon block adsorption filler, the air pressure in the negative pressure cylinder rises and then drops rapidly. The curve is roughly similar to a vertical line. As the amount of test gas filled increases, the remaining holding space in the negative pressure cylinder decreases. After the test gas in the negative pressure cylinder is filled, the air pressure in the negative pressure cylinder will slowly decrease until it stabilizes at a certain air pressure value. For example, after 12g of phosphine is filled, the air pressure value will rise rapidly, then slowly decrease over time and gradually stabilize at a certain air pressure platform. A curve similar to an L-shaped curve can be seen from the change of the air pressure in the negative pressure cylinder over time.

[0053] The filling process generally goes through three stages: pressure rise, pressure drop, and pressure stabilization. Therefore, in step S2, by real-time monitoring of the air pressure in the negative pressure cylinder, the delivery of test gas can be suspended when the air pressure in the negative pressure cylinder is too high, and the test gas can be refilled after the pressure drops, so that the negative pressure cylinder is maintained in a negative pressure state throughout the entire filling process, and this process is repeated until the adsorption saturation state is reached.

[0054] Furthermore, when filling the negative pressure cylinder with test gas, the temperature inside the negative pressure cylinder may rise. If the temperature inside the negative pressure cylinder is too high, the performance of the adsorption filler may be damaged.

[0055] For example, adsorbent packing is often loaded with gaseous substances. When the temperature inside the negative pressure cylinder rises, some of the loaded substances in the adsorbent packing will react, affecting the performance of the adsorbent packing. Furthermore, excessively high temperatures can damage the internal pore structure of the adsorbent packing, thus affecting the performance of the adsorbent packing itself.

[0056] Therefore, in order to reduce the probability that the adsorption capacity data obtained in the test deviates from the actual adsorption capacity due to damage of the adsorption filler during the adsorption process, and to further improve the accuracy of the test data, in some embodiments, in step S2, the temperature in the negative pressure cylinder can also be monitored in real time. When the temperature in the negative pressure cylinder is too high, the supply of test gas is stopped. After the temperature in the negative pressure cylinder drops, the test gas is continued to be filled, and this process is repeated until the adsorption saturation state is reached.

[0057] The present application does not limit the specific set temperature. It can be understood that the set temperature is the normal operating temperature of the adsorption material and will not be higher than the melting temperature of the adsorption filler and the load, and the temperature at which the porous structure deforms.

[0058] For example, when the adsorption filler is an asphalt-based material, the set temperature of the adsorption cylinder can be set to 60~80℃. If the asphalt-based adsorption filler is exposed to a high temperature of 60~80℃ for a long time, the internal pore structure will be destroyed and the performance will be affected.

[0059] In step S2, the present application does not limit the set flow rate of the test gas into the negative pressure cylinder. In some embodiments, the set flow rate can be 0.1-1 L / min. Filling the test gas at this flow rate can prevent excessive temperature rise in the negative pressure cylinder.

[0060] As an example, the set flow rate can be one of 0.1 L / min, 0.2 L / min, 0.3 L / min, 0.4 L / min, 0.5 L / min, 0.6 L / min, 0.7 L / min, 0.8 L / min, 0.9 L / min or 1.0 L / min, or a range between any two of them.

[0061] Because the adsorption rate of the adsorbent material gradually decreases as the filling process progresses, in order to maintain a negative pressure state throughout the entire filling process, in some embodiments, as the test gas is injected into the negative pressure cylinder at a set flow rate, the concentration of the test gas gradually decreases over time. As the filling process progresses, the concentration of the test gas decreases to accommodate the adsorption rate of the adsorbent material.

[0062] Alternatively, in other embodiments, the concentration of the test gas may be kept constant, and the injection flow gradient of the test gas may be reduced.

[0063] When the air pressure in the negative pressure cylinder detected in step S2 is maintained at the set air pressure value P1 within 12 hours, it means that the adsorption capacity of the adsorption filler in the negative pressure cylinder has reached saturation at the set air pressure value.

[0064] In step S2, this application does not limit the specific value of the set pressure value P1. Relevant personnel can set different set pressure values ​​P1 as needed to obtain the effective adsorption capacity of the adsorption filler at different set pressure values ​​P1. It is understood that the set pressure value P1 should be a negative pressure. Generally, it can be assumed that normal pressure is 760 Torr, and negative pressure should be less than 760 Torr.

[0065] As an example, the set pressure value P1 can be set to 700-750 Torr. 700-750 Torr is basically close to normal pressure. If the pressure in the negative pressure cylinder is stable at around 700-750 Torr within 12 hours, the adsorption capacity at this time can basically be determined as the maximum adsorption capacity of the adsorption filler in the negative pressure cylinder.

[0066] In some embodiments, after step S2 reaches the adsorption saturation state, the test gas can be stopped from being delivered, and the adsorption time from the start of filling the negative pressure cylinder with the test gas at the set flow rate to reaching the adsorption saturation state is recorded. The adsorption time can reflect the overall adsorption rate of the adsorption filler.

[0067] After reaching adsorption saturation in step S2, the filled weight M1 of the negative pressure cylinder is measured in step S3. The initial weight M0 of the negative pressure cylinder, when evacuated to the target negative pressure, is subtracted from the filled weight M1 to obtain the filler's adsorption capacity for the test gas at the set pressure. Placing the adsorbent filler in the negative pressure cylinder to test its performance simulates the actual filling process within the negative pressure cylinder and more accurately reflects the filler's adsorption capacity during the actual adsorption process.

[0068] Furthermore, in some embodiments, after the capacity test is completed, the test gas adsorbed by the adsorption filler in the negative pressure cylinder can be desorbed to extract the test gas adsorbed in the negative pressure cylinder.

[0069] During desorption, the pressure sensor displays the negative pressure cylinder's pressure and the electronic scale displays its weight in real time, plotting a weight-pressure curve. Correlating the negative pressure cylinder's pressure and weight reveals the amount of desorbed gas at each pressure, reflecting desorption efficiency. This weight-pressure curve allows users to determine the remaining test gas in the negative pressure cylinder based on the cylinder's pressure during subsequent use.

[0070] In actual use, the adsorption filler is usually used multiple times, and the adsorption filler will undergo multiple cycles of adsorption and desorption during actual use. However, if the number of cycles of use of the adsorption filler is too many, the performance of the adsorption filler will be reduced. Furthermore, the test method provided in the embodiment of the present application also includes: S5. Cycle life test: Repeat steps S1, S2, S3, and S4, recording the adsorption capacity in step S3 for each cycle. When the adsorption capacity decreases by 5% compared to the initial adsorption capacity at the first adsorption, the corresponding number of cycles represents the cycle life of the adsorption filler.

[0071] For example, when steps S1, S2, S3, and S4 are performed for the first time, the adsorption capacity obtained in step S3 can be referred to as the initial adsorption capacity. When steps S1, S2, S3, and S4 are repeated for the 200th time, if the adsorption capacity obtained in step S3 during the 200th cycle decreases by 5% compared to the initial adsorption capacity, the effective service life of the adsorption filler is 200 cycles.

[0072] It is understandable that in the cycle life test steps provided in the embodiments of the present application, when the adsorption capacity decreases by 5% compared to the initial adsorption capacity at the first adsorption, it means: when the adsorption capacity decreases by 5% or more for the first time compared to the initial adsorption capacity at the first adsorption, it does not mean that it must decrease by 5% to determine the service life. For example, the initial adsorption capacity is 100g, and the adsorption capacity obtained in step S3 at the 199th cycle is 94.5g, which does not meet the standard of a decrease of 5%. The adsorption capacity obtained in step S3 at the 200th cycle is 94g, a decrease of 6%. This is the first decrease of more than 5%, and it can be determined that the adsorption capacity of the adsorption filler is 200 times.

[0073] Furthermore, in step S4, the surface quality of the adsorption filler can also be tested during each cycle. If the number of cycles corresponding to the occurrence of pulverization of the adsorption filler is less than the number of cycles corresponding to a 5% decrease in adsorption capacity compared to the initial adsorption capacity during the first adsorption, the number of cycles corresponding to the occurrence of pulverization of the adsorption filler represents the cycle life of the adsorption filler. It is understood that after the surface quality is tested after the cycle is completed, that is, after step S4 is completed, the adsorption filler in the negative pressure cylinder is removed and the surface quality of the adsorption filler is tested. When removing the adsorption filler, a certain amount of the adsorption filler can be randomly removed, and it is not necessary to remove all of it.

[0074] For example, when part of the adsorption filler is pulverized after the 190th cycle, and the adsorption capacity obtained in step S3 during the 200th cycle decreases by 5% compared with the initial adsorption capacity, it can be further determined that the cycle life of the adsorption filler is 190 times.

[0075] The above method is used to test the adsorption capacity, adsorption rate, desorption condition and cycle life of the adsorption filler, which can guide the setting of filling parameters of negative pressure cylinders during the factory production process.

[0076] Further, see Figure 1The embodiment of the present application further provides a testing system 100 for implementing the above-mentioned testing method, comprising a negative pressure cylinder 1, an electronic scale 2, a vacuum pump 3, and a test gas delivery device 4. The negative pressure cylinder 1 is used to be placed on the electronic scale 2. A pressure sensor 5 is provided at the negative pressure cylinder 1 for detecting the air pressure within the negative pressure cylinder 1. The vacuum pump 3 can be selectively connected to the internal chamber of the negative pressure cylinder 1 to extract the gas within the negative pressure cylinder 1. The test gas delivery device 4 can be selectively connected to the internal chamber of the negative pressure cylinder 1 to deliver test gas to the negative pressure cylinder 1.

[0077] This application does not limit how the vacuum pump 3 can be selectively connected to the internal chamber of the negative pressure cylinder 1. In some embodiments, please continue to refer to Figure 1 The vacuum pump 3 is connected to the internal chamber of the negative pressure cylinder 1 through the first pipeline 6. The first pipeline 6 is provided with a first diaphragm valve 7. When the negative pressure cylinder 1 needs to be vacuumed, the first diaphragm valve 7 and the vacuum pump 3 can be opened.

[0078] Furthermore, the present application does not limit how the test gas delivery device 4 can be selectively connected to the internal chamber of the negative pressure cylinder 1. In some embodiments, please continue to refer to Figure 1 The test gas conveyor 4 is connected to the internal chamber of the negative pressure cylinder 1 through a second pipeline 8, and the second pipeline 8 is provided with a second diaphragm valve 9. When the negative pressure cylinder 1 needs to be filled with test gas, the second diaphragm valve 9 and the test gas conveyor 4 are opened. As an example, the test gas conveyor 4 can be a gas cylinder or other conventional special gas storage unit. The test gas conveyed by the test gas conveyor 4 can be a pure test gas, such as phosphine (6N purity). The test gas conveyed by the test gas conveyor 4 can also be a mixed gas of test gas and carrier gas, and the delivery concentration requirement can be selected according to the needs, and this application does not impose any restrictions.

[0079] Further, in some embodiments, please continue to refer to Figure 1 The test system 100 further includes a replacement gas conveyor 10 connected to the second pipeline 8 via a third pipeline 11, and the third pipeline 11 is provided with a third diaphragm valve 12. The second diaphragm valve 9 is located at the front end of the third pipeline 11. As an example, the replacement gas can be nitrogen, and the replacement gas conveyor 10 can be a nitrogen cylinder or a conventional single-digit storage unit. The replacement gas conveyor 10 is provided in the test system 100. When the negative pressure cylinder 1 needs to be removed after being filled, the replacement gas conveyor 10 can be used to replace the test gas in the pipeline as needed.

[0080] For further information, please refer to Figure 1The second pipeline 8 is further provided with a flow meter 13, a one-way valve 14 and a first pneumatic diaphragm valve 15 in sequence at the rear end of the second diaphragm valve 9. The pressure sensor 5 is provided in the second pipeline 8 between the first pneumatic diaphragm valve 15 and the negative pressure cylinder 1.

[0081] Further, in some embodiments, please continue to refer to Figure 1 Testing system 100 further includes a controller 16, which is signal-connected to first pneumatic diaphragm valve 15 and pressure sensor 5. Controller 16 is configured to close first pneumatic diaphragm valve 15 and suspend inflation when pressure sensor 5 detects a pressure between 700 and 750 torr. For example, controller 16 may be a PLC control system, and pressure sensor 5 may be a negative pressure gauge.

[0082] Further, in some embodiments, please continue to refer to Figure 1 The test system 100 further includes an exhaust gas processor 17. The outlet of the vacuum pump 3 is connected to the exhaust gas processor 17 via a fourth pipe 18. The fourth pipe 18 is provided with a fourth diaphragm valve 19. The exhaust gas processor 17 is a conventional exhaust gas treatment unit in the art and is not limited in this application.

[0083] Furthermore, a temperature sensor 20 is provided at the negative pressure cylinder 1 for measuring the temperature of the negative pressure cylinder 1. As an example, the temperature sensor 20 may be a thermometer.

[0084] Furthermore, in some embodiments, the testing system 100 further includes a temperature controller 21 , which is used to adjust the temperature of the negative pressure cylinder 1 .

[0085] As an example, the temperature controller 21 can be a conventional cooling device in the art. When the temperature of the negative pressure cylinder 1 is too high, the cooling device cools the negative pressure cylinder 1. For example, the temperature controller 21 can include a cooling barrel for placing the negative pressure cylinder 1. The cooling barrel has a double-layer structure, and a coolant delivery pipe is wound between the layers of the cooling barrel. The negative pressure cylinder 1 is placed in the cooling barrel. When the temperature sensor 20 detects that the temperature of the negative pressure cylinder 1 is too high, coolant can be supplied to the coolant delivery pipe. For example, the coolant can be cold water or other refrigerant.

[0086] Furthermore, in some embodiments, the testing system 100 further includes a timer (not shown in the figure) to facilitate timing during the testing process.

[0087] Furthermore, in some embodiments, the test system 100 further includes a gas detector 22 for detecting whether a test gas leak occurs during the test process of the test system 100. The gas detector 22 can be a conventional gas detection device in the art and is not limited in this application.

[0088] When using the above-mentioned testing system 100 to test the performance of the adsorption filler, the adsorption filler is placed in a negative pressure cylinder, the bottle valve of the negative pressure cylinder 1 is closed, and all diaphragm valves and pneumatic diaphragm valves are in a closed state.

[0089] S1. Then, open the first diaphragm valve 7 and the fourth diaphragm valve 19, start the vacuum pump 3, and observe the pressure sensor 5. When the pressure sensor 5 displays the target negative pressure value P0, close the vacuum pump 3 and the first diaphragm valve 7 to determine whether the negative pressure maintenance of the pipeline between the first pneumatic diaphragm valve 15 and the first diaphragm valve 7 is qualified. If qualified, open the first diaphragm valve 7 again, open the bottle valve of the negative pressure cylinder 1, turn on the vacuum pump 3, and determine the pressure state in the negative pressure cylinder 1 by observing the pressure sensor 5. When the pressure sensor 5 displays the target negative pressure value P0 again, turn on the electronic scale 2, weigh the negative pressure cylinder 1, and obtain the initial weight M0 of the negative pressure cylinder 1.

[0090] S2, then close the first diaphragm valve 7 and the vacuum pump 3, open the second diaphragm valve 9, set the flow meter 13 to the set flow value, then open the first pneumatic diaphragm valve 15, and then deliver the test gas to the negative pressure cylinder 1. During this period, the pressure sensor 5 is continuously observed. When the pressure approaches the positive pressure, for example, when it is between 700 and 750 torr, the controller 16 controls the first pneumatic diaphragm valve 15 to close and suspend inflation. After the air pressure in the negative pressure cylinder 1 drops, the controller 16 opens the first pneumatic diaphragm valve 15 and continues to inflate. At the same time, the temperature in the negative pressure cylinder 1 is continuously monitored through the temperature sensor 20. When the temperature is too high, the controller 16 closes the first pneumatic diaphragm valve 15 and suspends inflation. The temperature in the negative pressure cylinder 1 is adjusted by the temperature controller 21. After the temperature in the negative pressure cylinder 1 drops, the controller 16 opens the first pneumatic diaphragm valve 15. When the pressure value displayed by pressure sensor 5 remains stable at the set pressure value P1 for 12 hours, it indicates that the adsorption filler has reached saturation at that pressure value. During the filling process, if the test gas delivered by test gas conveyor 4 is high-purity test gas, in some embodiments, the third diaphragm valve 12 may be opened to introduce nitrogen to dilute the test gas, in order to reduce the concentration of effective test gas components (e.g., phosphine) in the test gas filled into the negative pressure cylinder 1 as needed. A timer may also be used to record the adsorption time from the start of test gas filling into the negative pressure cylinder 1 to the point of adsorption saturation. This adsorption time represents the adsorption rate of the adsorption filler.

[0091] S3. Then, the negative pressure cylinder 1 after adsorption is weighed again using the electronic scale 2 to obtain the weight after filling M1, and the adsorption capacity of the adsorption filler at the set air pressure value P0 can be obtained as M1-M0.

[0092] After filling is completed, when the negative pressure cylinder 1 needs to be removed, the second diaphragm valve 9 and the bottle valve of the negative pressure cylinder 1 can be closed, the first diaphragm valve 7 and the vacuum pump 3 can be opened, the third diaphragm valve 12 can be opened, nitrogen can be introduced, and the pipeline can be circulated and purged. The exhaust gas extracted by the vacuum pump 3 enters the exhaust gas processor 17 through the fourth pipeline 18 for exhaust gas treatment. After the purge is completed, the third diaphragm valve 12, the first pneumatic diaphragm valve 15, the first diaphragm valve 7 and the fourth diaphragm valve 19 are closed. That is, the replacement gas such as nitrogen delivered by the replacement gas conveyor 10 can be mixed with the test gas delivered by the test gas conveyor 4 to adjust the concentration of the test gas filled in the negative pressure cylinder 1, and the test gas remaining in the pipeline can be replaced as needed.

[0093] S4. When desorption is required, the first diaphragm valve 7 and the valve of the negative pressure cylinder 1 are opened, and the vacuum pump 3 is turned on to extract the test gas from the negative pressure cylinder 1. Alternatively, the pressure of the negative pressure cylinder 1 can be monitored in real time using the pressure sensor 5, and the weight of the negative pressure cylinder can be recorded in real time using the electronic scale 2. A weight-pressure curve can be plotted to reflect the desorption efficiency of the adsorption filler.

[0094] S5. When cycle life testing is required, repeat steps S1, S2, S3, and S4 above, with steps S1 to S4 being one cycle. Record the adsorption capacity obtained in step S3 for each cycle. The adsorption capacity obtained in step S3 during the first cycle is the initial adsorption capacity. When the adsorption capacity obtained in step S3 during subsequent cycles decreases by 5% compared to the initial adsorption capacity, the number of cycles corresponding to that cycle represents the cycle life of the adsorption filler. For example, if the adsorption capacity after 200 cycles decreases by 5% compared to the initial adsorption capacity, the cycle life of the adsorption filler is 200 cycles.

[0095] The performance testing method of the adsorption filler in the negative pressure cylinder of the present application is further described in detail below with reference to the examples.

[0096] Example 1 Example 1 provides a method for testing the performance of an adsorption filler. The adsorption filler is a porous carbon block and the test gas is phosphine gas (6N). The test method is as follows: S1. Initial state calibration: Place 200g of adsorbent carbon block into a negative pressure cylinder (model ZF-1088). Evacuate the cylinder to the target negative pressure, P0, and record the initial weight of the cylinder. P0 is 0.5mbar and M0 is 1200g.

[0097] S2. Test Gas Injection: Fill the negative pressure cylinder with test gas at a set flow rate of 0.1 L / min. Monitor the pressure in the negative pressure cylinder in real time to maintain a constant negative pressure state until adsorption saturation is reached. Adsorption saturation occurs when the pressure in the negative pressure cylinder stabilizes at the set pressure of 750 Torr within 12 hours. Record the rate at which the pressure drops by 100 mbar as the fill weight increases during the filling process, as shown in Table 1.

[0098] Table 1

[0099] As can be seen from Table 1, when the negative pressure cylinder is first filled, the internal storage space is the largest, so the pressure in the negative pressure cylinder drops the fastest. As the filling weight increases, the remaining storage space in the negative pressure cylinder gradually decreases, and the subsequent pressure drop becomes slower and slower.

[0100] S3. Determine the adsorption capacity: After reaching adsorption saturation, stop adding the test gas and obtain the filled weight M1 of the negative pressure cylinder. The adsorption capacity of the adsorbent at the set pressure P1 is M1-M0. The filled weight M1 is 1240 g, and the adsorption capacity of the adsorbent at a set pressure P1 of 750 torr is M1-M0, which is 40 g.

[0101] S4, desorption: extract the test gas adsorbed in the negative pressure cylinder, monitor the pressure of the negative pressure cylinder and the weight reduction ΔM of the negative pressure cylinder in real time, and draw a curve of ΔM changing with pressure, such as Figure 2 shown.

[0102] from Figure 2 It can be seen that when the air pressure in the negative pressure cylinder drops from the full state to 400 torr, approximately 1g of phosphine is output. When the air pressure drops from 400 torr to 200 torr, approximately 5g is output. When the air pressure drops from 20 torr to 100 torr, approximately 3g is output. When the air pressure drops from 100 torr to 5 torr, approximately 14.65 torr is output. This shows that at the beginning of the desorption stage, the air pressure in the negative pressure cylinder drops significantly, and the number of grams of phosphine discharged slowly decreases, indicating that the desorption efficiency of phosphine is low in the initial stage. In the later stage, within a smaller range of air pressure reduction, the number of grams of phosphine output by the negative pressure cylinder gradually increases, indicating that the desorption speed is accelerated in the later stage. In addition, during use, users can also observe the air pressure of the negative pressure cylinder and combine it with Figure 2 , you can know roughly how many grams of phosphine are left in the negative pressure cylinder.

[0103] S5. Cycle life test: Repeat steps S1, S2, S3, and S4, and record the adsorption capacity obtained in step S3 during each cycle. When the cycle reaches 200, the adsorption capacity decreases by 5% compared with the initial capacity, indicating that the effective service life of the adsorption filler is 200 cycles.

[0104] Examples 2 to 7 The difference between Examples 2 to 7 and Example 1 is that Examples 2 to 7 respectively deliver test gas into the negative pressure cylinder at different set flow rates of 0.5 L / min, 1 L / min, 2 L / min, 4 L / min, 5 L / min, and 6 L / min, and record the temperature rise in the negative pressure cylinder, as shown in Table 2.

[0105] Table 2

[0106] As can be seen from Table 2, the temperature inside the negative pressure cylinder gradually increases with increasing filling flow rate. However, since the volume of the adsorbent filler inside the negative pressure cylinder is constant, the temperature rise in Examples 5 to 7 is similar. Therefore, to prevent the temperature inside the negative pressure cylinder from rising too high, it is best to fill the negative pressure cylinder with test gas at a set flow rate of 0.1 to 1 L / min.

[0107] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A method for testing the performance of adsorption fillers in negative pressure cylinders, characterized in that: include: S1. Initial state calibration: Place the adsorption filler into a negative pressure cylinder, evacuate the negative pressure cylinder to a target negative pressure value P0, and record the initial weight M0 of the negative pressure cylinder at this time; S2. Test gas injection: Fill the negative pressure cylinder with test gas at a set flow rate, monitor the pressure in the negative pressure cylinder in real time, and keep the cylinder in a negative pressure state until it reaches adsorption saturation; the adsorption saturation state means that the pressure in the negative pressure cylinder is stable at the set pressure value P1 within 12 hours; S3. Determine the adsorption capacity: After reaching the adsorption saturation state, stop filling the test gas and obtain the filled weight M1 of the negative pressure cylinder; the adsorption capacity of the adsorption filler at the set pressure value P1 is M1-M0.

2. The testing method according to claim 1, wherein: In step S2, the set flow rate is 0.1-1 L / min; the adsorption time from the start of filling the test gas into the negative pressure cylinder to the adsorption saturation state is monitored, and the adsorption time represents the adsorption rate of the adsorption filler.

3. The testing method according to claim 1, wherein: In step S2, the temperature of the negative pressure cylinder is monitored in real time, and when the temperature is higher than a set temperature, the filling of the test gas is stopped; Optionally, the material of the adsorption filler is an asphalt-based material, the test gas contains phosphine, and the set temperature is 60-80°C.

4. The testing method according to any one of claims 1 to 3, characterized in that: The test gas includes a carrier gas and a test gas; in step S2, when the test gas is filled into the negative pressure cylinder according to the set flow rate, the concentration of the test gas in the test gas decreases gradually over time; Optionally, the set air pressure value P1 is 700~750torr.

5. The testing method according to claim 1, wherein: The test method further includes step S4 after step S3, where S4 is a desorption step: The test gas adsorbed in the negative pressure cylinder is extracted, the gas pressure and weight of the negative pressure cylinder are monitored in real time, and a curve showing the change of the weight with the gas pressure is drawn.

6. The testing method according to claim 5, characterized in that: The test method further comprises: S5. Cycle life test: repeat steps S1, S2, S3 and S4, and record the adsorption capacity in step S3 during each cycle; when the adsorption capacity decreases by 5% compared with the initial adsorption capacity during the first adsorption, the corresponding number of cycles represents the cycle life of the adsorption filler; Optionally, in step S1, the target negative pressure value is 0.1-1 mbar.

7. The testing method according to claim 6, characterized in that: In step S4, the surface quality of the adsorption filler in the negative pressure cylinder is observed after each cycle. If the number of cycles corresponding to the occurrence of pulverization of the adsorption filler is less than the number of cycles corresponding to a 5% decrease in the adsorption capacity compared to the initial adsorption capacity at the first adsorption, the number of cycles corresponding to the occurrence of pulverization of the adsorption filler represents the cycle life of the adsorption filler.

8. A test system for implementing the test method according to any one of claims 1 to 7, characterized in that: include: A negative pressure steel cylinder, which is used to be placed on an electronic scale; a pressure sensor is provided at the negative pressure steel cylinder for detecting the air pressure in the negative pressure steel cylinder; a vacuum pump, the vacuum pump being selectively connected to the inner chamber of the negative pressure cylinder to extract the gas in the negative pressure cylinder; The test gas delivery device is selectively connected to the inner chamber of the negative pressure cylinder to deliver the test gas to the negative pressure cylinder.

9. The test system according to claim 8, characterized in that: The vacuum pump is connected to the inner chamber of the negative pressure cylinder through a first pipeline, and the first pipeline is provided with a first diaphragm valve; the test gas conveyor is connected to the inner chamber of the negative pressure cylinder through a second pipeline, and the second pipeline is provided with a second diaphragm valve; Optionally, the test system further comprises a replacement gas conveyor connected to the second pipeline via a third pipeline; the third pipeline is provided with a third diaphragm valve; Optionally, the second pipeline is further provided with a flow meter, a one-way valve and a first pneumatic diaphragm valve in sequence at the rear end of the second diaphragm valve; the pressure sensor is provided in the second pipeline between the first pneumatic diaphragm valve and the negative pressure cylinder; Optionally, the test system further includes an exhaust gas processor, the outlet of the vacuum pump is connected to the exhaust gas processor via a fourth pipe, and the fourth pipe is provided with a fourth diaphragm valve.

10. The test system according to claim 9, characterized in that: The negative pressure cylinder is also provided with a temperature sensor for measuring the temperature inside the negative pressure cylinder; Optionally, the testing system further comprises a temperature controller, and the temperature controller is used to adjust the temperature of the negative pressure cylinder.

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