Fault detection device and detection method of mass flow controller and vacuum equipment

Abstract

The invention discloses a fault detection device and method for a mass flow controller and vacuum equipment. The fault detection device comprises a switch module, a gas storage module, a pressure measurement module, a vacuum pump module and a control module. The gas inlet end of the gas storage module is connected with the to-be-tested mass flow controller through the switch module, and the gas outlet end of the gas storage module is connected with the process cavity through the switch module; the pressure measurement module is connected with the gas storage module to collect pressure data of the gas storage module; the vacuum pump is connected with the gas storage module or the process cavity; the control module is connected with the to-be-detected mass flow controller, the control module is configured to detect whether the to-be-detected mass flow controller has a fault according to the pressure data and the flow data of the to-be-detected mass flow controller, gas flow detection of the MFC is carried out in a normal temperature range, and the fault detection device is simple in structure and convenient to operate. And transformation of existing vacuum equipment is facilitated.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of equipment detection, and in particular, to a fault detection device, a detection method, and a vacuum device for a mass flow controller. Background Art

[0002] In the fields of semiconductors, flat panel displays, and photovoltaics, vacuum devices are widely used in the product manufacturing process. These fields have extremely high requirements for product accuracy and performance. The vacuum environment can effectively reduce the interference of external factors on the manufacturing process. Thin film deposition and etching are common process technologies among them. Thin film deposition aims to precisely construct a functional thin film on a substrate material, and etching is to remove some or all areas of the existing substrate to form the required microstructures.

[0003] Ensuring the stability and repeatability of the process is crucial for this industry. This is directly related to the consistency and reliability of product quality and is a necessary condition for achieving large-scale and high-quality production. The process gas flow rate, as a key process parameter, has a significant impact on the final performance of the product. Usually, the process gas is precisely controlled by a Mass Flow Controller (MFC) to enter the vacuum reaction chamber. The accurate control of the gas flow rate depends on the state of the MFC. When faults such as "internal leakage and zero drift" occur in the MFC, the flow rate set by the process recipe will deviate, resulting in changes in the film thickness and composition, or over-etching and precision deviation in the etching process. When troubleshooting process anomalies, it will take a lot of time to accurately judge the gas flow rate, thus affecting the production capacity of the equipment. Summary of the Invention

[0004] The present invention provides a fault detection device, a detection method, and a vacuum device for a mass flow controller, which can realize the gas flow rate detection of the MFC at room temperature, and the fault detection device has a simple structure and is convenient for the transformation of existing vacuum devices.

[0005] In a first aspect, the embodiments of the present invention provide a fault detection device for a mass flow controller, including: a switch module, a gas storage module, a pressure measurement module, a vacuum pump module, and a control module;

[0006] The inlet end of the gas storage module is connected to the mass flow controller to be tested through the switch module, and the outlet end of the gas storage module is connected to the process chamber through the switch module;

[0007] The pressure measurement module is connected to the gas storage module to collect the pressure data of the gas storage module; the vacuum pump is connected to the gas storage module or the process chamber;

[0008] The control module is connected to the mass flow controller to be tested, and the control module is configured to detect whether there is a fault in the mass flow controller to be tested according to the pressure data and the flow data of the mass flow controller to be tested.

[0009] Optionally, the switch module includes a first switch unit and a second switch unit;

[0010] The first end of the first switch unit is connected to the mass flow controller to be tested, the second end of the first switch unit is connected to the inlet end of the gas storage module, the outlet end of the gas storage module is connected to the first end of the second switch unit, and the second end of the second switch unit is connected to the process chamber.

[0011] Optionally, the switch module further includes a third switch unit;

[0012] The first end of the third switch unit is connected to the first end of the first switch unit, and the second end of the third switch unit is connected to the process chamber.

[0013] Optionally, when there are multiple mass flow controllers to be tested, the switch module further includes a fourth switch unit;

[0014] The fourth switch unit is arranged between the mass flow controller to be tested and the first end of the first switch unit.

[0015] Optionally, the fault detection device for the mass flow controller further includes a temperature control module, which is connected to the gas storage module, and the temperature control module is used to control the temperature in the gas storage module to be the detection temperature.

[0016] In a second aspect, an embodiment of the present invention provides a vacuum device, including the fault detection device for the mass flow controller according to any embodiment of the present invention.

[0017] In a third aspect, an embodiment of the present invention provides a method for detecting a fault of a mass flow controller, which is executed by a fault detection device for a mass flow controller. The fault detection device for a mass flow controller includes: a switch module, a gas storage module, a pressure measurement module, a vacuum pump module and a control module;

[0018] The vacuum pump module evacuates the gas storage module;

[0019] The switch module cuts off the passage between the outlet end of the gas storage module and the process chamber;

[0020] The mass flow controller to be tested outputs gas at a first flow rate, and the pressure measurement module collects the pressure data of the gas storage module;

[0021] The control module obtains the actual second flow rate according to the pressure data, compares the first flow rate with the second flow rate, obtains the error value of the mass flow controller to be tested, and determines whether there is a fault in the mass flow controller to be tested according to the error value.

[0022] Optionally, the switch module includes a first switch unit and a second switch unit;

[0023] The method includes:

[0024] Turn on the first switch unit and the second switch unit, and use the vacuum pump module to evacuate the gas storage module so that the air pressure of the gas storage module is less than or equal to 1 Torr;

[0025] Pre-ventilate the mass flow controller to be tested to maintain the ventilation stability of the mass flow controller to be tested, where the pre-ventilation time is greater than or equal to 5 s;

[0026] Close the second switch unit to cut off the passage between the gas outlet end of the gas storage module and the process chamber, control the mass flow controller to be tested to output gas at a first flow rate, the first flow rate is the flow rate data of the mass flow controller to be tested, the first flow rate is the same as the flow rate in the case of pre-ventilation and is in the range of 30%-100% of the maximum flow rate of the mass flow controller to be tested, the ventilation time range at the first flow rate is 0.5 s - 600 s, record the pressure data no less than 2 times, and calculate the actual second flow rate according to the gas flow formula;

[0027] The control module compares the first flow rate with the second flow rate to obtain the relative error σ of the mass flow controller to be tested, compares the relative error σ with the preset error value, and determines that there is a fault in the mass flow controller to be tested when the relative error σ is greater than the preset error value, and determines that the mass flow controller to be tested is in a normal state when the relative error σ is less than the preset error value;

[0028] Open the second switch unit, and use the vacuum pump module to evacuate the gas storage module so that the air pressure of the gas storage module is less than or equal to 1 Torr.

[0029] Optionally, the preset error value is any value between 0.5% and 20%.

[0030] Optionally, before pre-ventilating the mass flow controller to be tested, it further includes:

[0031] Turn off the first switch unit and the second switch unit, test the leakage rate of the gas storage module, and the test time range is greater than or equal to 10 s; determine that the leakage rate of the gas storage module is less than or equal to 0.1 Torr·L / s, then continue with the subsequent steps; otherwise, stop the fault detection.

[0032] The fault detection device for the mass flow controller provided by the embodiment of the present invention separately sets a gas storage module and uses the gas storage module to provide a detection volume for gas, so that the gas flow of the MFC can be detected at room temperature, avoiding measurement errors caused by high temperatures. Using the on or off state of the switch module, the vacuum pump module is connected to the gas storage module for evacuation, and the passage for the MFC to input gas to the gas storage module during the test is connected. The pressure measurement module collects the pressure data of the gas storage module, and the control module detects whether the MFC has a fault according to the pressure data and the flow data of the MFC. The fault detection device has a simple structure and is convenient for the transformation of existing vacuum equipment. Description of the Drawings

[0033] Figure 1 It is a schematic structural diagram of a fault detection device for a mass flow controller provided by an embodiment of the present invention;

[0034] Figure 2 It is a schematic structural diagram of another fault detection device for a mass flow controller provided by an embodiment of the present invention;

[0035] Figure 3 It is a flowchart of a fault detection method for a mass flow controller provided by an embodiment of the present invention;

[0036] Figure 4 It is a flowchart of another fault detection method for a mass flow controller provided by an embodiment of the present invention. Detailed Embodiments

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0038] In the fields of semiconductors, flat panel displays, and photovoltaics, vacuum equipment is widely used in the product manufacturing process. These fields have extremely high requirements for product accuracy and performance, and the vacuum environment can effectively reduce the interference of external factors on the manufacturing process.

[0039] Thin film deposition and etching are common process technologies among them. Thin film deposition aims to precisely construct functional thin films on substrate materials, while etching is to precisely process the deposited thin films to form the desired microstructures.

[0040] Ensuring the stability and repeatability of the process is crucial for this industry. This is directly related to the consistency and reliability of product quality and is a necessary condition for achieving large-scale and high-quality production. As a key process parameter, the process gas flow rate has a significant impact on the final performance of the product.

[0041] A mass flow controller (MFC) is used to precisely control the flow rate of process gas into the process chamber. It realizes precise regulation of the gas flow rate according to preset parameters. However, during the operation of the MFC, faults such as "internal leakage" and "zero drift" may occur. Once such faults occur, the flow rate set by the process recipe will deviate from the expected value.

[0042] The flow rate deviation will have adverse effects on both thin film deposition and etching processes. In terms of thin film deposition, it will cause changes in the thickness and composition of the thin film, thereby affecting the optical, electrical, and chemical properties of the product. In the etching process, abnormal flow rate will make the etching rate unstable, resulting in deviations in the etching depth and pattern accuracy, and unable to precisely form the desired microstructures, seriously affecting the functionality and yield of the product. In actual production, if abnormalities occur in the thin film or etching effect, it is necessary to use professional detection equipment and techniques to check whether the flow rate is accurately introduced, which will consume a lot of time. This will not only reduce the equipment productivity but also increase the production cost, having an adverse impact on the economic benefits and market competitiveness of the industry.

[0043] In view of this, Figure 1 This invention provides a structural schematic diagram of a fault detection device for a mass flow controller for the embodiments of the present invention. Refer to Figure 1 , including: a switch module 110, a gas storage module 120, a pressure measurement module 130, a vacuum pump module 140, and a control module;

[0044] The inlet end of the gas storage module 120 is connected to the mass flow controller 150 to be tested through the switch module 110, and the outlet end of the gas storage module 120 is connected to the process chamber 160 through the switch module 110;

[0045] The pressure measurement module 130 is connected to the gas storage module 120 to collect the pressure data of the gas storage module 120; the vacuum pump is connected to the gas storage module 120 or the process chamber 160;

[0046] The control module (not shown) is connected to the MFC 150 to be tested, and the control module is configured to detect whether there is a fault in the MFC 150 to be tested according to the pressure data and the flow rate data of the mass flow controller 150 to be tested.

[0047] Specifically, the fault detection device is connected to the pipeline between the MFC 150 to be tested and the process chamber 160. Among them, the inlet end and the outlet end of the gas storage module 120 are respectively connected to the output end of the MFC 150 to be tested and the process chamber 160 through the switch module 110. By controlling the on or off state of the switch module 110, the gas output by the MFC can only enter the gas storage module 120, or the gas output by the MFC 150 to be tested enters the process chamber 160 through the gas storage module 120. Among them, the gas storage module 120 can be set to be tested in the normal temperature range to avoid test errors caused by gas expansion in high temperature situations. Exemplarily, the normal temperature range can be 25°C - 40°C.

[0048] The vacuum pump module 140 can be connected to the gas storage module 120, and the vacuum pump module 140 can also be connected to the process chamber 160. Cooperating with the passage in the on or off state of the switch module 110, the gas storage module 120 can be evacuated. In the embodiment of the present invention, exemplarily, the vacuum pump module 140 is connected to the process chamber 160. When evacuating the gas storage module 120, the switch module 110 can conduct the passage between the inlet end of the gas storage module 120 and the output end of the MFC 150 to be tested, and the passage between the outlet end of the gas storage module 120 and the process chamber 160.

[0049] Exemplarily, the fault detection process: First, use the vacuum pump module 140 to evacuate the gas storage module 120. After the vacuum degree of the gas storage module 120 meets the requirements, exemplarily, the air pressure range of the gas storage module 120 is 0.05 Torr - 1 Torr, and the MFC 150 to be tested can be pre-aerated for a certain period of time to maintain the output stability of the MFC 150 to be tested. Then start the test. The switch module 110 can cut off the passage between the outlet end of the gas storage module 120 and the process chamber 160. The MFC 150 to be tested outputs gas at the first flow rate (the flow rate data of the MFC 150 to be tested). The pressure measurement module 130 collects the pressure data of the gas storage module 120. The control module can calculate the actual second flow rate based on the pressure data. The control module compares the first flow rate and the second flow rate, and the error value of the MFC 150 to be tested can be obtained. Here, the error value can be expressed as the relative error σ, relative error Compare the relative error σ with the preset error value. When the relative error σ is greater than the preset error value, it indicates that the MFC 150 to be tested has a fault. When the relative error σ is less than the preset error value, it indicates that the MFC 150 to be tested is in a normal state. Exemplarily, the preset error value can be set to any value between 0.5% and 20%. For example, when the preset error value is taken as 5%, when σ < 5%, it indicates that the MFC 150 to be tested is in a normal state. When σ > 5%, it indicates that the MFC 150 to be tested has a fault.

[0050] Exemplarily, the process of calculating the actual second flow rate by the control module based on the pressure data can be calculated through the gas flow formula.

[0051] The gas flow formula can be expressed as:

[0052]

[0053] Wherein, V is the volume of the gas storage module 120, P atm is the standard atmospheric pressure, T is the temperature of the gas storage module 120, is the amount of change of the pressure data of the gas storage module 120 with time.

[0054] Wherein,

[0055]

[0056] Pn is the pressure data of the gas storage module 120 at the moment of tn. Optionally, the volume of the gas storage module 120 can be 1L - 5L, which can not only meet the application requirements but also avoid too large a volume, resulting in a larger overall volume and being unfavorable for the transformation of the vacuum equipment.

[0057] The fault detection device of the mass flow controller provided by the embodiment of the present invention, by separately setting the gas storage module 120 and using the gas storage module 120 to provide the detection volume of the gas, can detect the gas flow rate of the MFC 150 to be measured at room temperature, avoid the measurement error caused by the high temperature, use the on or off state of the switch module 110 to realize the connection of the vacuum pump module 140 to evacuate the gas storage module 120, and the connection of the path for the MFC 150 to be measured to input gas to the gas storage module 120 during the test process, use the pressure measurement module 130 to collect the pressure data of the gas storage module 120, and the control module detects whether the MFC 150 to be measured has a fault according to the pressure data and the flow rate data of the MFC 150 to be measured. The fault detection device has a simple structure and is convenient for the transformation of the existing vacuum equipment.

[0058] Continue to refer to Figure 1 , optionally, the switch module 110 includes a first switch unit 111 and a second switch unit 112;

[0059] The first end of the first switch unit 111 is connected to the MFC 150 to be measured, the second end of the first switch unit 111 is connected to the intake end of the gas storage module 120, the outlet end of the gas storage module 120 is connected to the first end of the second switch unit 112, and the second end of the second switch unit 112 is connected to the process chamber 160.

[0060] Specifically, the first switch unit 111 is disposed on the pipeline between the MFC 150 to be measured and the intake end of the gas storage module 120, and the second switch unit 112 is disposed on the pipeline between the outlet end of the gas storage module 120 and the process chamber 160. When evacuating the gas storage module 120, the first switch unit 111 and the second switch unit 112 are turned on, and the vacuum pump module 140 can evacuate the gas storage module 120. After the vacuum degree of the gas storage module 120 meets the requirements, the MFC 150 to be measured can be pre-aerated for a certain period of time, and then the second switch unit 112 is cut off. The MFC 150 to be measured outputs gas at a first flow rate (the flow rate data of the MFC 150 to be measured). The pressure data of the gas storage module 120 is collected by the pressure measurement module 130, and the control module can calculate the actual second flow rate according to the pressure data. After the test is completed, the second switch unit 112 can be turned on again, and the vacuum pump module 140 can evacuate the gas storage module 120 to avoid gas residue in the gas storage module 120 and improve the test safety.

[0061] Continue to refer to Figure 1 , optionally, the switch module 110 further includes a third switch unit 113;

[0062] The first end of the third switch unit 113 is connected to the first end of the first switch unit 111, and the second end of the third switch unit 113 is connected to the process chamber 160.

[0063] Specifically, during the normal process, the gas output by the MFC 150 to be measured can enter the process chamber 160 through the path where the third switch unit 113 is located. That is to say, a gas supply path is provided between the MFC 150 to be measured and the process chamber 160, and the third switch unit 113 is used to control the on or off of the gas supply path. During the fault test process, the third switch unit 113 is in the off state, while during the normal process, the third switch unit 113 is in the on state to realize normal process gas supply. Thus, the test path and the gas supply path can be separated without affecting the normal application of the vacuum equipment.

[0064] Figure 2 FIG. is a schematic structural diagram of a fault detection device for another mass flow controller provided by an embodiment of the present invention. Refer to Figure 2 , when there are multiple MFCs 150 to be measured, the switch module 110 further includes a fourth switch unit 114;

[0065] A fourth switch unit 114 is disposed between the MFC 150 to be measured and the first end of the first switch unit 111.

[0066] Specifically, during the process, multiple gases often pass through the corresponding MFCs 150 to be measured and are controlled to enter the process chamber 160. Therefore, when there are multiple MFCs 150 to be measured, each MFC 150 to be measured can be connected to the first switch unit 111 through a fourth switch unit 114. That is to say, for the detection of the MFCs 150 to be measured, any one of the MFCs 150 to be measured can be selected for detection through the fourth switch unit 114, so as to locate the specific fault of the MFC 150 to be measured.

[0067] Exemplarily, the fault detection process for locating the MFC 150 to be measured: Turn on one of the fourth switch units 114, the first switch unit 111, and the second switch unit 112, and use the vacuum pump module 140 to evacuate the gas storage module 120. After the vacuum degree of the gas storage module 120 meets the requirements, the MFC 150 to be measured can be pre-aerated for a certain period of time to maintain the aeration stability of the MFC 150 to be measured. Then the test starts. The second switch unit 112 can cut off the passage between the gas outlet end of the gas storage module 120 and the process chamber 160. The MFC 150 to be measured outputs gas at the first flow rate (the flow rate data of the MFC 150 to be measured). The pressure data of the gas storage module 120 is collected through the pressure measurement module 130, and the control module can calculate the actual second flow rate based on the pressure data. The control module compares the first flow rate and the second flow rate to obtain the relative error of the MFC 150 to be measured. Compare the relative error σ with the preset error value. When the relative error σ is greater than the preset error value, it indicates that the MFC 150 to be measured has a fault. When the relative error σ is less than the preset error value, it indicates that the MFC 150 to be measured is in a normal state. After the test is completed, turn on the second switch unit 112 again, and the vacuum pump module 140 can evacuate the gas storage module 120.

[0068] Cut off the fourth switch unit 114 that has been turned on, select to turn on another fourth switch unit 114, so as to replace the MFC 150 to be measured for detection, and repeat the process after starting the test. By performing the test in sequence, the fault detection of all the MFCs 150 to be measured can be completed, so as to quickly identify which gas's MFC 150 to be measured fault causes the process abnormality. Realize the positioning detection in the case of multiple MFCs 150 to be measured, and the test can be completed only by using the single gas input by the MFC 150 to be measured, without the need to add a reference gas to complete the test, which simplifies the test process.

[0069] See Figure 1 and Figure 2, Optionally, the fault detection device of the mass flow controller further includes a temperature control module 170. The temperature control module 170 is connected to the gas storage module 120 and is used to control the temperature in the gas storage module 120 to the detection temperature. Specifically, the gas storage module 120 is independently arranged. Compared with the high-temperature working environment of the process chamber 160, the gas storage module 120 can be set to be tested in the normal temperature range to avoid test errors caused by gas expansion in high-temperature situations. The temperature control module 170 can detect the temperature in the gas storage module 120 and adjust it according to the temperature in the gas storage module 120 so that the temperature in the gas storage module 120 is the detection temperature. Exemplarily, the detection temperature can be the temperature in the normal temperature range. For example, the detection temperature can be 25°C - 40°C.

[0070] Figure 3 The flowchart of a fault detection method for a mass flow controller provided by an embodiment of the present invention is combined with Figure 1 , This embodiment is applicable to the fault detection situation of the to-be-tested MFC 150. This method can be executed by the fault detection device of the mass flow controller, and this device can be implemented in a hardware and / or software manner. This method specifically includes the following steps:

[0071] S110. The vacuum pump module 140 performs a vacuum pumping process on the gas storage module 120;

[0072] Specifically, the fault detection device is connected to the pipeline between the to-be-tested MFC 150 and the process chamber 160. Among them, the inlet end and the outlet end of the gas storage module 120 are respectively connected to the output end of the to-be-tested MFC 150 and the process chamber 160 through the switch module 110. By controlling the on or off state of the switch module 110, the gas output by the MFC can only enter the gas storage module 120, or the gas output by the to-be-tested MFC 150 enters the process chamber 160 through the gas storage module 120. Among them, the gas storage module 120 can be set to be tested in the normal temperature range to avoid test errors caused by gas expansion in high-temperature situations. Exemplarily, the normal temperature range can be 25°C - 40°C.

[0073] The vacuum pump module 140 can be connected to the gas storage module 120, and the vacuum pump module 140 can also be connected to the process chamber 160. Cooperating with the passage under the on or off state of the switch module 110, the vacuum pumping of the gas storage module 120 can be achieved. In the embodiment of the present invention, exemplarily, the vacuum pump module 140 is connected to the process chamber 160. When performing a vacuum pumping on the gas storage module 120, the switch module 110 can conduct the passage between the inlet end of the gas storage module 120 and the output end of the to-be-tested MFC 150, and the passage between the outlet end of the gas storage module 120 and the process chamber 160.

[0074] Fault detection process: First, use the vacuum pump module 140 to evacuate the gas storage module 120. After the vacuum degree of the gas storage module 120 meets the requirements, for example, the air pressure range of the gas storage module 120 is 0.05 Torr - 1 Torr, the MFC 150 to be tested can be pre-aerated for a certain period of time to maintain the output stability of the MFC 150 to be tested, and then the subsequent tests can be started.

[0075] S120. The switch module 110 cuts off the passage between the gas outlet end of the gas storage module 120 and the process chamber 160.

[0076] S130. The MFC 150 to be tested outputs gas at a first flow rate, and the pressure measurement module 130 collects the pressure data of the gas storage module 120.

[0077] S140. The control module obtains the actual second flow rate according to the pressure data, compares the first flow rate with the second flow rate to obtain the error value of the MFC 150 to be tested, and determines whether there is a fault in the MFC 150 to be tested according to the error value.

[0078] Specifically, the control module can calculate the actual second flow rate according to the pressure data. By comparing the first flow rate with the second flow rate, the control module can obtain the relative error of the MFC 150 to be tested, and compare the relative error σ with the preset error value. When the relative error σ is greater than the preset error value, it indicates that there is a fault in the MFC 150 to be tested. When the relative error σ is less than the preset error value, it indicates that the MFC 150 to be tested is in a normal state. For example, the preset error value can be set to any value between 0.5% and 20%. For example, when the preset error value is 5%, when σ < 5%, it indicates that the MFC 150 to be tested is in a normal state. When σ > 5%, it indicates that there is a fault in the MFC 150 to be tested.

[0079] Figure 4 The flowchart of another fault detection method for a mass flow controller provided by an embodiment of the present invention is shown in Figure 4 , including:

[0080] S210. Turn on the first switch unit 111 and the second switch unit 112, and use the vacuum pump module 140 to evacuate the gas storage module 120 so that the air pressure of the gas storage module 120 is less than or equal to 1 Torr. For example, the air pressure range of the gas storage module 120 can be 0.05 Torr - 1 Torr.

[0081] S220. The MFC 150 to be tested is pre-aerated for a certain period of time to maintain the aeration stability of the MFC 150 to be tested. Among them, the pre-aeration time is greater than or equal to 5 s. For example, the pre-aeration time can be 5 s - 15 s.

[0082] S230. The second switch unit 112 cuts off the passage between the gas outlet end of the gas storage module 120 and the process chamber 160. The MFC 150 to be tested outputs gas at a first flow rate (the flow rate data of the MFC 150 to be tested). Among them, the first flow rate can be the same as the flow rate in the case of pre-ventilation. Among them, the first flow rate can be 30%-100% of the maximum flow rate of the MFC 150 to be tested. The time of ventilating at the first flow rate can be 0.5 s - 600 s. Record the pressure data no less than 2 times. For example, record the pressure data every 0.5 s. According to the gas flow formula, the actual second flow rate can be calculated.

[0083] S240. The control module compares the first flow rate and the second flow rate, and the relative error of the MFC 150 to be tested can be obtained. Compare the relative error σ with the preset error value. When the relative error σ is greater than the preset error value, it indicates that the MFC 150 to be tested has a fault. When the relative error σ is less than the preset error value, it indicates that the MFC 150 to be tested is in a normal state. The preset error value can be set to any value between 0.5% and 20%. For example, the preset error value is taken as 5%. When σ < 5%, it indicates that the MFC 150 to be tested is in a normal state. When σ > 5%, it indicates that the MFC 150 to be tested has a fault.

[0084] S250. Turn on the second switch unit, and use the vacuum pump module 140 to evacuate the gas storage module 120 so that the air pressure of the gas storage module 120 is less than or equal to 1 Torr. Exemplarily, the air pressure range of the gas storage module 120 can be 0.05 Torr - 1 Torr.

[0085] In some embodiments, the leakage rate of the gas storage module 120 can also be detected before S220. That is to say, after the vacuum pump module 140 evacuates the gas storage module 120, turn off the first switch unit 111 and the second switch unit 112, and test the leakage rate of the gas storage module 120. The test time range is greater than or equal to 10 s. Exemplarily, the test time can be 10 s - 60 s. Among them, the leakage rate of the gas storage module 120 should be less than or equal to 0.1 Torr·L / s. If the requirements are met, continue with the subsequent steps; otherwise, stop the fault detection.

[0086] When there are multiple MFCs 150 to be tested, the MFC 150 to be tested for detection can be replaced, and steps S210 - S250 are repeated to test each MFC 150 to be tested in turn, and the fault detection of all MFCs 150 to be tested can be completed, so as to quickly find out which gas's MFC 150 to be tested causes the process anomaly.

[0087] An embodiment of the present invention further provides a vacuum device. Among them, the vacuum device may include a plasma enhanced chemical vapor deposition (PECVD) vacuum device, a magnetron sputtering vacuum device, a laser sputtering deposition vacuum device, etc. Since it has the fault detection device of the mass flow controller according to any embodiment of the present invention, it has the same beneficial effects and will not be elaborated here.

[0088] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fault detection device for a mass flow controller, characterized in that, Including: a switch module, a gas storage module, a pressure measurement module, a vacuum pump module, and a control module; The inlet end of the gas storage module is connected to the mass flow controller to be measured through the switch module, and the outlet end of the gas storage module is connected to the process chamber through the switch module; The pressure measurement module is connected to the gas storage module to collect the pressure data of the gas storage module; the vacuum pump is connected to the gas storage module or the process chamber; The control module is connected to the mass flow controller to be measured, and the control module is configured to detect whether there is a fault in the mass flow controller to be measured according to the pressure data and the flow data of the mass flow controller to be measured.

2. The fault detection device of the mass flow controller according to claim 1, characterized in that The switch module includes a first switch unit and a second switch unit; The first end of the first switch unit is connected to the mass flow controller to be measured, the second end of the first switch unit is connected to the inlet end of the gas storage module, the outlet end of the gas storage module is connected to the first end of the second switch unit, and the second end of the second switch unit is connected to the process chamber.

3. The fault detection device of the mass flow controller according to claim 2, characterized in that The switch module further includes a third switch unit; The first end of the third switch unit is connected to the first end of the first switch unit, and the second end of the third switch unit is connected to the process chamber.

4. The fault detection device of the mass flow controller according to claim 3, characterized in that, When there are multiple mass flow controllers to be measured, the switch module further includes a fourth switch unit; The fourth switch unit is arranged between the mass flow controller to be measured and the first end of the first switch unit.

5. The fault detection device for a mass flow controller according to any one of claims 1-4, characterized in that, It further includes a temperature control module, the temperature control module is connected to the gas storage module, and the temperature control module is used to control the temperature in the gas storage module to the detection temperature.

6. A vacuum device, characterized in that, A fault detection device for a mass flow controller according to any one of claims 1-5.

7. A fault detection method for a mass flow controller, characterized in that Executed by a fault detection device for a mass flow controller, the fault detection device for a mass flow controller includes: a switch module, a gas storage module, a pressure measurement module, a vacuum pump module, and a control module; The vacuum pump module evacuates the gas storage module; The switch module cuts off the passage between the outlet end of the gas storage module and the process chamber; The mass flow controller to be measured outputs gas at a first flow rate, and the pressure measurement module collects the pressure data of the gas storage module; The control module obtains an actual second flow rate according to the pressure data, compares the first flow rate and the second flow rate, obtains an error value of the mass flow controller to be measured, and judges whether there is a fault in the mass flow controller to be measured according to the error value.

8. The fault detection method of the mass flow controller according to claim 7, characterized in that The switch module includes a first switch unit and a second switch unit; The method includes: Turn on the first switch unit and the second switch unit, and use the vacuum pump module to evacuate the gas storage module to make the air pressure in the gas storage module less than or equal to 1 Torr; Pre-ventilate the mass flow controller to be measured to maintain the ventilation stability of the mass flow controller to be measured, wherein the pre-ventilation time is greater than or equal to 5 s; Close the second switch unit to cut off the passage between the gas outlet end of the gas storage module and the process chamber, control the mass flow controller under test to output gas at a first flow rate, where the first flow rate is the flow rate data of the mass flow controller under test, and the first flow rate is the same as the flow rate in the pre-ventilation case and is within the range of 30%-100% of the maximum flow rate of the mass flow controller under test. The time range for ventilating at the first flow rate is 0.5 s - 600 s. Record the pressure data no less than 2 times, and calculate the actual second flow rate according to the gas flow formula; The control module compares the first flow rate and the second flow rate to obtain the error value as the relative error σ, and compares the relative error σ with the preset error value. When the relative error σ is greater than the preset error value, it is determined that the mass flow controller under test has a fault. When the relative error σ is less than the preset error value, it is determined that the mass flow controller under test is in a normal state; Open the second switch unit, and use the vacuum pump module to evacuate the gas storage module to make the air pressure of the gas storage module less than or equal to 1 Torr.

9. The fault detection method of the mass flow controller according to claim 8, characterized in that, The preset error value is any value between 0.5% - 20%.

10. The fault detection method of the mass flow controller according to claim 9, wherein, Before pre-ventilating the mass flow controller under test, it further includes: Close the first switch unit and the second switch unit, test the leakage rate of the gas storage module, and the test time range is greater than or equal to 10 s; if it is determined that the leakage rate of the gas storage module is less than or equal to 0.1 Torr·L / s, then continue with the subsequent steps; otherwise, stop the fault detection.

Images