Flow ratio controller system and flow ratio controller method

Abstract

To provide a flow ratio controller system.SOLUTION: A flow ratio controller system includes an inlet receiving a total inlet fluid flow from one or more inlet channels, distribution channels fluidically connected to the inlet and arranged in parallel in a branching flow path downstream of the inlet, and a controller. The distribution channels include a hybrid distribution channel. The controller selectively operates in alternative control modes including a flow verification control mode and a flow ratio control mode. In the flow verification control mode, the controller calculates a calibrated value for a reference volume by using measurements from a mass flow meter in the hybrid distribution channel, and then calculates a target channel calibration value for the mass flow meter in the target distribution channel.SELECTED DRAWING: Figure 1A

Description

Technical Field

[0001] In the field of semiconductor manufacturing, achieving consistency in the production of semiconductor devices is a challenge. Manufacturers frequently encounter difficulties in producing reproducible and replicable semiconductor devices due to variations in the processing parameters of each process chamber. These variations include differences in flow rate, temperature control, chamber surface and volume conditions, plasma frequency and density, and geometric factors. To address this challenge, manufacturers have developed the practice of establishing a standard or "golden chamber" - a process chamber that is used to calibrate other process chambers in the same manufacturing setting.

[0002] In this calibration process, various process variables are adjusted to match the performance of multiple process chambers. The most commonly adopted method for this purpose is to re-calibrate or finely tune the process recipe set values of mass flow controllers (MFCs).

Summary of the Invention

Problems to be Solved by the Invention

[0003] A practice widely carried out among some manufacturers is to flow a gas stream within a single sealed and evacuated process chamber and measure the rate of pressure rise (ROR) inside it. By incorporating the temperature measurement value and the rate of pressure rise and applying the equation of the ideal gas law, the mass flow rate can be calculated. This practice is known as the "chamber pressure rise rate." However, this method introduces errors due to inaccuracies in the known volume of each process chamber or slight differences in chamber volume, thereby hindering the ability to align processes between different process chambers.

[0004] Another conventional approach involves the use of a common flow verification system that employs various basic flow measurement or metering concepts. In this system, the MFCs from all chambers flow into a centrally located flow verifier. This method is generally more effective than the "chamber pressure rise rate" method for chamber matching in order to eliminate variations caused by different chamber volumes. However, this central verification system has several drawbacks. These include a significant addition of hardware, piping, and associated costs, a long gas flight time (ToF) from the MFC to the flow verification system due to long piping distances, and the limitation that only one MFC at a time can flow into the verification system, requiring a serial or sequential approach for MFC verification and distortion. These factors contribute to longer system startup and qualification times, as well as increased costs for the manufacturer. **Means for Solving the Problems**

[0005] To address the above problems, there is provided a flow rate ratio control system comprising an inlet configured to receive a total inflow fluid flow rate, and a plurality of flow paths fluidly connected to the inlet and arranged in parallel in a branched flow path downstream of the inlet. The plurality of flow paths each comprise a respective flow rate control valve and are configured to convey respective portions of the total inlet fluid flow rate. The plurality of flow paths include a hybrid flow path. A control device is operably coupled to each of the plurality of flow paths. The control device is configured to selectively operate in alternative control modes including a flow rate verification control mode and a flow rate ratio control mode. In the flow rate verification control mode, the control device performs a first pressure change rate test on a first target flow path extending from the inlet through a reference volume to the hybrid flow path, using measurements from a mass flow meter in the hybrid distribution flow path, thereby calculating a calibration value for the reference volume. Further, in the flow rate verification control mode, the control device is also configured to verify the flow rate values measured by the mass flow meters in the target distribution flow paths of the plurality of distribution flow paths other than the hybrid distribution flow path, and perform a second pressure change rate test on a second target flow path extending from the inlet through the reference volume to the target flow path, using the calibrated reference volume value, thereby calculating a target flow path calibration value for the mass flow meter of the target flow path. In the flow rate verification mode, the control device is further configured to calibrate the mass flow meter in the target distribution flow path using the target flow path calibration value. In the flow rate ratio control mode, the control device is configured to control each of the plurality of distribution flow paths including the hybrid distribution flow path according to respective flow rate ratio set values for each distribution flow path.

[0006] This abstract is intended to introduce selected concepts in a simplified form that will be described in detail below. This abstract is not intended to identify key features or essential features of the subject matter claimed in the claims, nor is it intended to limit the scope of the subject matter claimed in the claims. It should be noted that the subject matter claimed is not limited to implementations that solve any or all of the disadvantages noted in any part of this disclosure.

Brief Description of the Drawings

[0007]

Figure 1A

Figure 1B

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Figure 10

Figure 11

Mode for Carrying Out the Invention

[0008] In view of the above problems, referring to FIG. 1, as a first embodiment configuration, a flow rate ratio control system 10 is provided. The flow rate ratio control system 10 includes a flow splitter subsystem 12 and an inlet 17 configured to receive an upstream total inlet fluid flow rate and then flow through the flow splitter subsystem 12. For example, the inlet 17 may receive the upstream fluid flow rate from a collective first manifold 15 configured to collect the flow rates from the outlets of one or more inlet channels 18. In the example of FIG. 1, the flows from each of the inlet channels 18A-F are collected in the first manifold 15, and then the combined flow that converges at the inlet 17 of the flow splitter subsystem 12 of the flow rate ratio control system 10 is sent. Each of the upstream mass flow controllers MFC1 to MFCN may be fluidly connected upstream of the inlet 17 of each of the one or more inlet channels 18. The first manifold 15 may be formed of a manifold block with channels formed therein, similar to the second manifold 16 described below, or may be formed in another form, such as via one or more pipes with appropriate channels formed therein.

[0009] The flow rate ratio control system 10 may be configured as a gas supply device enclosed within a housing. The fluid lines described herein may be implemented using flow blocks, pipes, or alternative channel structures. Although six mass flow controllers MFC1 to MFC6 are depicted in FIG. 1, the number is not particularly limited and may be less than or more than six, as indicated by the notation MFCN.

[0010] Inlet 17 is configured to receive the total inlet fluid flow from one or more inlet flow paths 18. The flow divider subsystem 12 of the flow rate ratio control system 10 is further configured to include a plurality of distribution flow paths 14 including a hybrid distribution flow path 14C that flows gas to a process chamber PC in which processes such as deposition and etching are performed during semiconductor manufacturing. The hybrid distribution flow path 14C is used in two different ways (i.e., for verification of the reference capacity and for conveying a part of the total flow rate) according to the operation mode, and thus is referred to as a "hybrid" flow path in this specification. The distribution flow paths 14 are fluidly connected to an inlet 17 formed on the upstream side of the downstream manifold 16. The distribution flow paths 14 are arranged in parallel in the downstream manifold 16 in the branch flow paths downstream of the inlet 17 and are connected to respective outlets 19 that direct a fluid flow into the process chamber PC. The manifolds of the plurality of distribution flow paths 14 are each provided with a variable flow rate control valve CV1-CV3 and are configured to convey respective portions of the total inlet fluid flow entering the flow splitter subsystem 12. The variable flow rate control valves CV1-CV3 are integrated within a flow path-specific flow rate control device 13 that can measure either the mass flow rate or the volumetric flow rate and are arranged on each distribution flow path 14.

[0011] Although three distribution flow paths 14 are depicted in FIG. 1, the number is not particularly limited, and it will be understood that it may be less than or more than three, as indicated by the notation of flow path N. For example, flow path N may be an additional distribution flow path in the branch flow path downstream of inlet 17. In some configurations, flow path N may be provided without a flow rate control valve and may be configured to convey respective portions of the total inlet fluid flow.

[0012] As shown in FIG. 1B, the distribution channel 14 branches from the manifold at a point upstream of the branch point for the hybrid distribution channel 14C, and may also include the VM4 downstream of the branch point and the high-flow channel N+1 including the isolation valves IV7 and IV8 on its upstream and downstream sides. The measured temperature sensor TM4 and the measured pressure sensor PM4 may be provided in the high-flow distribution channel N+1. The configuration of FIG. 1B is otherwise the same as that of FIG. 1A, and further description of FIG. 1B is omitted for the sake of brevity.

[0013] Returning to FIG. 1A, at the inlet point to the flow splitter subsystem 12, the primary isolation valve IV1 is arranged upstream of the inlet 17. The additional isolation valves IV2, IV3, and IV5 are arranged immediately upstream of the corresponding flow control valves CV1, CV2, and CV3 of the distribution channels 14A-C, respectively. In the flow rate ratio control channel 14A, the isolation valve IV2 is arranged upstream of the channel 14A, the isolation valve IV3 is arranged immediately upstream of the channel 14B, and the isolation valve IV5 is arranged immediately upstream of the hybrid channel 14C.

[0014] Each of the distribution channels 14A and 14B that is not the hybrid distribution channel 14C includes a valve position sensor Z configured to measure the opening degrees of the flow control valves CV1 and CV2, a temperature sensor T configured to measure the temperature of the fluid in the distribution channel 14, a flow resistance R of a fixed geometry configured to restrict the fluid flow, an upstream pressure sensor P1 configured to measure the pressure of the fluid upstream of the flow resistance R, and a downstream pressure sensor P2 configured to measure the pressure of the fluid downstream of the flow restrictor R, and are arranged in this order in the downstream direction of the channel along each distribution channel 14. The flow control valves CV1-CV3 are usually arranged upstream of the flow resistance R, but as shown by the dashed line 23A, they can also be arranged downstream of the flow resistance R. Each distribution channel 14 is configured with each outlet 19 of the flow splitter subsystem 12. The upstream pressure sensor P1 and the downstream pressure sensor P2 can be configured as diaphragm-insulated pressure sensors.

[0015] The hybrid distribution channel 14C includes a pair of measurement pressure sensors PM2 and PM3, and a pair of measurement temperature sensors TM3 and TM4 disposed on both sides of the flow rate limiter RM. In this example, the hybrid distribution channel 14C includes a flow rate control valve CV3, a first internal volume VM2, a measurement temperature sensor TM2 configured to measure the temperature of the first internal volume VM2, an upstream measurement temperature sensor TM3 and an upstream measurement pressure sensor PM2, a flow rate limiter RM, a downstream measurement temperature sensor TM4 and a downstream measurement pressure sensor PM3, and a second internal volume VM3, and they are arranged in this order in the downstream flow direction of the hybrid distribution channel 14C.

[0016] The accuracy of the upstream measurement pressure sensor PM2 and the downstream measurement pressure sensor PM3 may be within an accuracy value of ±0.1% of FS (full scale). The temperature coefficients of the upstream measurement temperature sensor TM3 and the downstream measurement temperature sensor TM4 may be within a range where the accuracy value is ±0.02% of FS / °C (full scale). The upstream measurement pressure sensor PM2 and the downstream measurement pressure sensor PM3 may be MEMS (microelectromechanical system) vibration type pressure sensors. The diameter of the flow path of the flow rate limiter RM may be less than 50 microns. The length of the flow path in the flow rate limiter RM may be 10 millimeters or more and 50 millimeters or less. The flow rate limiter RM may be made of a ceramic material, and the internal flow path in the flow rate limiter RM may be cut and shaped within the ceramic material in order to accurately adjust the length and volume dimensions of the internal flow path in the flow rate limiter RM.

[0017] The flow rate ratio control system 10 further includes a control device 22 operatively coupled to each of the variable flow rate control valves CV1 - CV3 of the plurality of distribution channels 14 in order to control each of the variable flow rate control valves CV1 - CV3 by feedback control. The variable flow rate control valves CV1 - CV3 may be, for example, proportional flow rate control valves.

[0018] The control device 22 is configured to selectively operate in an alternative control mode including a flow verification control mode and a flow ratio control mode. In the flow verification control mode, the control device 22 performs a first pressure change rate test on a first target flow path extending from the inlet 17 through the reference volume VM1 to the hybrid distribution flow path 14C, and uses the measured value from the mass flow meter in the hybrid distribution flow path 14C to thereby calculate a corrected value of the reference volume VM1. In the flow verification control mode, the control device 22 is further configured to verify the flow rate value measured by the mass flow meter in the target distribution flow path (for example, 14A) of a plurality of distribution flow paths 14A, 14B other than the hybrid distribution flow path 14C. In the second target flow path extending from the inlet 17 through the reference volume VM1 to the target distribution flow path (for example, 14A), a second pressure change rate test is performed using the measured values from the temperature sensor and the pressure sensor in the target distribution flow path (for example, 14A) and the corrected value of the reference volume VM1, thereby calculating a target flow path corrected value of the mass flow meter in the target distribution flow path 14C.

[0019] In the flow ratio control mode, the control device 22 is configured to control each of the plurality of distribution flow paths 14 including the hybrid distribution flow path 14C and the target distribution flow path (for example, 14A) according to the respective flow ratio set values of each distribution flow path 14 using the calibrated mass flow meter. The mass flow meter in the hybrid distribution flow path 14C may be embodied, for example, as a pair of measurement pressure sensors PM2, PM3 and a pair of measurement temperature sensors TM3, TM4 disposed on both sides of the flow restrictor RM.

[0020] The control device 22 may be configured to verify at least partially the flow of one of the inlet flow paths 18 or one or more of the distribution flow paths 14 by performing at least partially a pressure rise rate test (ROR test) or a pressure drop rate test (ROF test) using the ideal gas law (PV = nRT) and a reference volume provided in the branch flow path downstream of the inlet 17.

[0021] The reference volume may be the upstream reference volume VM1 provided in the downstream manifold 16 of the branch flow path on the downstream side of the inlet 17 and upstream of the flow rate limiter RM of the mass flow meter located in the hybrid distribution flow path 14C. In this embodiment, the upstream measurement pressure sensor PM1 and the upstream measurement temperature sensor TM1 are disposed within the upstream reference volume VM1 and are operably coupled to the control device 22. The upstream reference volume VM1 may be defined as a segment of the flow path extending from the primary isolation valve IV1 to the downstream valves IV2, IV3, and IV5.

[0022] In another implementation, the reference volume may be the downstream reference volume VM3 provided on the branch flow path downstream of the flow rate limiter RM of the mass flow controller located in the hybrid distribution flow path 14C.

[0023] Alternatively, the reference volume may be the intermediate reference volume VM2 provided in the branch flow path on the downstream side of the inlet 17 and upstream of the flow rate limiter RM of the mass flow meter located in the hybrid distribution flow path 14C. In this implementation, the measurement temperature sensor TM2 is disposed in the intermediate reference volume VM2.

[0024] The downstream manifold 16 includes the upstream measurement pressure sensor PM1 and the upstream measurement temperature sensor TM1 disposed within the upstream reference volume VM1 and operably coupled to the control device 22.

[0025] The control device 22 includes a processing circuit 22A, a volatile memory 22B such as a random access memory (RAM), and a non-volatile memory 22C such as a read-only memory (ROM), a flash memory, or a hard drive. When the non-volatile memory 22C is executed by the processing circuit 22A using a part of the volatile memory 22B, it stores program instructions that instruct the processing circuit 22A to perform the control processing described herein on the flow splitter subsystem 12. In some embodiments, the control device 22 may be configured as a system-on-module (SOM). The processing circuit 22A may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or another type of microprocessor, and may be, for example, a multi-core processor. The control device 22 may be operably coupled to the flow splitter subsystem 12 via the network 21 or a direct data connection. Optionally, the control device 22 may also be operably coupled to the MFC1-N of the inlet channel 18 via the network 21 or a direct data connection.

[0026] In some embodiments, a control microprocessor specific to a channel can be included within each distribution channel, and it will be understood that it includes the memory and processor functions used to control the flow control device arranged in that channel. It will be understood that the microprocessor for one of the channels can be programmed to execute the functions of the control device 22. When such a configuration is adopted, the channel having a microprocessor configured to operate as the control device 22 is called the master channel.

[0027] In one embodiment where the flow splitter subsystem 12 consists of the flow ratio control channels 14A, 14B, and the hybrid distribution channel 14C, the flow verification of the flow splitter subsystem 12 is performed by closing the isolation valves IV2, IV3, and IV4 while leaving the isolation valve IV5 open so that the fluid passes only through the hybrid distribution channel 14C, where the flow rate is measured. The calculation of the flow rate for flow control or verification may involve the use of a digital twin model of the flow restrictor RM that incorporates hydrodynamic equations taking into account the exact geometry of the internal flow path within the flow restrictor RM, similar to the characteristics of the fluid flowing through the flow restrictor RM.

[0028] This can be achieved by closing the main isolation valve IV1 together with IV2, IV3, and IV5, and then opening the valves IV5 and IV6 downstream of the channel 14C. Next, the control device 22 uses a calibrated total inflow rate having a first predetermined mass flow rate value to establish a controlled compression or decompression of the reference volume VM1. To achieve this, the control valve CV3, RM of the target distribution channel 14C may be adjusted to achieve a controlled decompression of the upstream reference volume VM1.

[0029] Next, during the controlled compression or decompression, the control device 22 measures the temperature change and pressure change in the hybrid distribution flow path 14C using the temperature sensor and pressure sensor in the hybrid distribution flow path 14C, respectively. To measure the temperature change and pressure change, the control device 22 may measure the initial pressure and initial temperature in the hybrid distribution flow path 14C and the subsequent pressure and subsequent temperature as a result of the controlled compression or decompression. For example, the hybrid distribution flow path 14C may be employed to measure the pressure decay (rate of pressure change or decrease) in the VM1 using signals from the upstream measurement pressure sensor PM1 and upstream measurement temperature sensor TM1 disposed within the reference volume VM1 during controlled decompression. The temperature sensor TM1 simultaneously measures the temperature of the first upstream volume VM1 and, in combination with the calculation of the rate of change (ROC) based on the gas law, compares the change in mass flow rate indicated by the hybrid distribution flow path 14C with the pressure and temperature values measured by the pressure sensor PM1 and temperature sensor TM1, respectively, to evaluate the volume VM1.

[0030] Next, the control device 22 calculates a calibration value for the reference volume based on the measured temperature change, measured pressure change, first predetermined mass flow rate value, and gas constant. The calibration value for the upstream reference volume VM1 may be calculated based on the measured pressure decay, and the calculated calibration value may then be stored in the non-volatile memory 22C. The calibration value for the reference volume VM1 may be calculated using the ideal gas law (PV = nRT) with the measured initial pressure, measured initial temperature, measured later pressure, measured later temperature, gas constant, and the value of the mass flow rate of the calibrated total inlet flow.

[0031] The calibrated first upstream volume VM1 is then used as an established parameter and benchmark for subsequent evaluation of the flow dynamics within the other target distribution flow paths 14A, 14B. This process includes a series of steps to ensure that the flow characteristics of these flow paths 14A, 14B are within the desired specifications for stable and reliable performance.

[0032] In the flow verification control mode, in order to verify the flow rate value measured by the mass flow meter in the target flow path (e.g., 14A), the control device 22 is configured to control the valve along the branch flow path to establish a second target flow path between the inlet and the target flow path (e.g., 14A), and the second target flow path includes the reference volume VM1. This can be achieved by closing the main isolation valve IV1. Next, while the second target flow path is established using a calibrated total inlet flow rate having a second predetermined mass flow rate value, the control device 22 establishes a controlled compression or decompression of the reference volume VM1. Pressurization may be achieved by closing the main isolation valve IV1, effectively sealing the system to prevent external influences. When the system is isolated in this way, the pressurized volume VM1 becomes a static environment where any variations are due only to the behavior of the flow path under test.

[0033] While the second target flow path is established, the control device 22 measures the pressure change and temperature change using the temperature sensor and pressure sensor in the target flow path (e.g., 14A) during the controlled compression or decompression. In this example, the downstream isolation valve IV2 or IV3 is systematically opened according to the flow path (14A or 14B) to be calibrated, while the other flow paths remain isolated. This focused approach enables the individual evaluation of the flow rate characteristics of each flow path without interference from parallel flow paths.

[0034] When the flow path to be calibrated is flow path 14A, the control valve CV1 and the R of the target distribution flow path 14A are controlled to achieve a controlled decompression of the upstream reference volume VM1 passing through the target distribution flow path 14A. When the isolation valve IV2 is opened and fluid starts to flow through the flow path 14A, the pressure in the first upstream volume VM1 begins to decrease. The pressure decrease is measured using the signals from the upstream measurement pressure sensor P1 and the upstream measurement temperature sensor P2 arranged in the reference volume R during the controlled decompression during the ROF test.

[0035] The calibration of flow path 14B and other flow paths is performed in the same manner as flow path 14A. The pressure decay of the upstream first volume VM1 provides information regarding the characteristics of flow path 14A. This includes the structural characteristics of flow path 14A, including cross-sectional area, surface roughness, and the presence of any flow resistance. The rate of pressure drop of the upstream first volume VM1 is recorded over the entire pressure decay process.

[0036] Next, the control device 22 calculates the flow rate based on the rate of change through the target distribution flow path 14A based on the measured pressure change, the measured temperature change, the calibration value of the reference volume VM1, and the second predetermined mass flow rate value. This can be achieved, for example, by measuring the temperature at TM1 and the pressure at PM1 at two points during the rate of change test and using the calibration value of the reference volume of VM1 to calculate the mass flow rate using the ideal gas law described above.

[0037] The control device calculates the flow limiter-based flow rate through the target flow path based on the flow limiter dimensions of the flow limiter R within the target distribution flow path 14A and the second predetermined mass flow rate value. This can be achieved, for example, by a mass flow meter provided in the target distribution flow path 14A measuring the mass flow rate across the fluid flow limiter within the target distribution flow path 14A and using the measured values from the pressure sensors P1 and P2 and the temperature sensor T. Next, based on the comparison between the calculated rate-of-change-based flow rate and the calculated flow limiter-based flow rate, the target flow path calibration value is calculated. The calculated target flow path calibration value is then stored in the non-volatile memory 22C. This method has been described using flow path A14A as an exemplary target distribution flow path, but it will be understood that this method can be applied to any of the flow paths 1 to N in FIG. 1A and also to flow path N + 1 in FIG. 1B.

[0038] Also, the control device 22 can execute a flow rate verification control mode to verify the mass flow rate measured by the target mass flow controller (e.g., MFC1). To perform the flow rate verification of the target mass flow controller, the calibration value of the target mass flow controller is calculated and used to calibrate the target mass flow controller in the target inlet flow path.

[0039] The fidelity of the performance of the target flow path 14A can be determined by comparing the observed pressure decay rate with the expected behavior predicted by the flow resistance model. If there is a difference between the observed velocity and the expected velocity, it may indicate problems such as blockage, wear, or defects in the flow path or the flow restrictor R, and further investigation and adjustment are required.

[0040] The first upstream volume VM1 may be calibrated in a chamber matching process. In such a process, the first upstream volume VM1 may be calibrated independently using the hybrid distribution flow path 14C or another calibration method such as a gravimetric calibration method. When calibration is performed using the hybrid distribution flow path 14C, the first upstream volume VM1 may be calibrated independently. Thus, the first upstream volume VM1 becomes the golden chamber to be matched by other chambers in the distribution flow path 14 downstream of the inlet 17 and the inlet flow path 18 upstream of the inlet 17, and the internal volumes of these flow paths 14, 18 can be calibrated using the first upstream volume VM1. For example, the flow rate calibration value of the upstream mass flow controller MFC1 of the upstream flow path 18A fluidly connected to the inlet 17 can be calculated using the calibration value of the upstream reference volume VM1. Thus, in the flow rate verification control mode, the control device 22 may be configured to verify the flow rate in each mass flow controller MFC1. Therefore, the reference volumes VM1, VM2, and VM3 may be used as non-drift references that can be cross-checked with other flow rate references and mass flow controllers.

[0041] Figure 2 shows an inlet configured to receive a total inlet fluid flow rate, fluidly connected to the inlet and arranged in parallel in a branched flow path downstream of the inlet, each of a plurality of distribution flow paths being provided with its respective valve and configured to convey a respective portion of the total inlet fluid flow rate, the plurality of distribution flow paths including a hybrid distribution flow path. The first method 100 may be implemented in the control device system 10 shown in FIG. 1 above, which includes a processing circuit and associated memory of a control device configured to selectively operate in an alternative control mode including a flow verification control mode and a flow ratio control mode. Alternatively, other suitable computing hardware and software may be utilized.

[0042] In 102, the method includes determining whether to operate in a flow verification control mode or a flow ratio control mode. This can be determined, for example, based on a control input or user input from the control device. In 104, the method includes executing a flow verification control mode, which includes performing a first pressure change rate test on a first target flow path extending from the inlet through a reference volume to the hybrid distribution flow path using measurements from a mass flow meter within the hybrid distribution flow path, thereby calculating a calibration value for the reference volume. In 108, the method includes executing a flow verification control mode, which includes verifying the flow rate values measured by a mass flow meter in a target distribution flow path of a plurality of distribution flow paths other than the hybrid distribution flow path, performing a second pressure change rate test on a second target flow path extending from the inlet through the reference volume to the target flow path using the calibration value of the reference volume, thereby calculating a target flow path calibration value for the mass flow meter within the target flow path. In addition to the calibration value, measurements from temperature sensors and pressure sensors within the target distribution flow path may be used in calculating the target flow path calibration value in 108. In 110, the method includes executing a flow verification control mode, which includes calibrating the mass flow meter within the target flow path using the target flow path calibration value.

[0043] In 106, this method includes each of a plurality of distribution channels including a hybrid distribution channel executing a flow rate ratio control mode in which the flow rate of each distribution channel is controlled according to the set value of the flow rate ratio of each distribution channel. Usually, this control ratio control mode is executed after calibration using a calibrated mass flow meter for the target distribution channel. In some embodiments, all distribution channels may be calibrated in this way before the execution of the flow rate ratio control mode.

[0044] FIG. 3 is a flowchart of a second method 200 for controlling a flow rate ratio control system in which a plurality of distribution channels are fluidly connected to an inlet of a manifold and arranged in parallel in a branch channel downstream of the inlet. Each of the plurality of distribution channels is provided with a respective control valve and is configured to convey a respective portion of the total inlet fluid flow rate, and the plurality of distribution channels includes a hybrid distribution channel. The second method 200 may be implemented in the control device system 10 illustrated in FIG. 1 above, and this control device system 10 includes a processing circuit and associated memory of a control device configured to selectively operate in an alternative control mode including a flow rate verification control mode and a flow rate ratio control mode. Alternatively, other suitable computing hardware and software may be utilized.

[0045] In 202, this method includes determining whether to operate in either the flow rate verification control mode or the flow rate ratio control mode. In 204, this method includes adjusting the control valve to verify the flow rate of one of the inlet channels or one or more of the distribution channels by performing an on-site drop speed test to determine the calibration value of the upstream reference volume in the flow rate verification control mode. In 206, in the flow rate ratio control mode, the control valve is adjusted to control the flow rate of each of the plurality of distribution channels according to the set value of the flow rate ratio of each.

[0046] At 208, the method includes performing an in-situ falling speed test to determine a calibration value for the target distribution channel. At step 210, the method includes calculating a flow calibration value of an upstream mass flow controller fluidly connected to an inlet of the upstream channel using a calibration value of the upstream reference volume.

[0047] Figure 4 is a flowchart of a third method 300 showing the execution of a first pressure change rate test described at 104 of a first method 100.

[0048] At 302, the method includes controlling a valve along a branch channel to establish a first target channel. At 304, the method includes establishing a controlled compression or decompression of a reference volume using a calibrated total inlet flow rate having a first predetermined mass flow rate value. At 306, the method includes measuring temperature changes and pressure changes within a hybrid distribution channel using temperature sensors and pressure sensors within the hybrid distribution channel during the controlled compression or decompression. At 308, the method includes calculating a calibration value of the reference volume based on the measured temperature changes, the measured pressure changes, the first predetermined mass flow value, and the gas constant. At 310, the method includes storing the calculated calibration value of the reference volume.

[0049] Figure 5 is a flowchart of a fourth method 400 showing the execution of an in-situ falling speed test to determine a calibration value of an upstream reference volume described at 204 of a second method 200.

[0050] At 402, the method includes pressurizing an upstream reference volume of the manifold. At 404, the method includes adjusting a control valve of the hybrid distribution flow path to achieve a controlled depressurization of the upstream reference volume. At 406, the method includes measuring pressure decay in the ROF test using signals from an upstream measured pressure sensor and an upstream measured temperature sensor disposed in the upstream reference volume during the controlled depressurization. At 408, the method includes calculating a calibration value for the upstream reference volume based on the measured pressure decay. At 410, the method includes storing the calculated calibration value.

[0051] FIG. 6 is a flowchart of a fifth method 500 showing verification of a flow rate value measured by a mass flow meter in a target flow path in the flow rate verification control mode described at 108 of the first method 100.

[0052] At 502, the method includes controlling a control valve along the branch flow path to establish a second target flow path between the inlet and the only target distribution flow path, the second target flow path including a reference volume. At 504, the method includes establishing a controlled compression or depressurization of the reference volume while the second target flow rate path is established using a calibrated total inlet flow rate having a second predetermined mass flow rate value. At 506, the method includes measuring pressure and temperature changes using temperature and pressure sensors within the target distribution flow path during the controlled compression or depressurization while the second target flow rate path is established. At 508, the method includes calculating a flow rate based on a rate of change through the target flow path based on the measured pressure change, the measured temperature change, a calibration value of the reference volume, and the second predetermined mass flow rate value. At 510, the method includes calculating a flow rate based on a flow rate limiter through the target flow path based on the flow rate limiter dimensions of a flow rate limiter within the target flow path and the second predetermined mass flow rate value. At 512, the method includes calculating a target flow path calibration value based on a comparison between the flow rate based on the calculated rate of change and the flow rate based on the calculated controller. At 514, the method includes storing the calculated target flow path calibration value.

[0053] Figure 7 is a flowchart of a sixth method 600 showing the implementation of an in-situ falling speed test to determine the calibration value of a target delivery channel, as described in 208 of the second method 200.

[0054] At 602, the method includes pressurizing an upstream reference volume. At 604, the method includes adjusting a control valve of the target channel to achieve a controlled depressurization of the upstream reference volume through the target channel.

[0055] At 606, the method includes measuring pressure decay using signals from an upstream measured pressure sensor and an upstream measured temperature sensor disposed within the reference volume during the controlled depressurization. At 608, the method includes calculating a flow rate based on the velocity reduction through the target channel based on the measured pressure decay and the calibration value of the upstream reference volume.

[0056] At 610, the method includes calculating a throttle-based flow rate through the target flow channel based on the dimensions of the throttle in the target flow channel. At 612, the method includes calculating a target channel calibration value based on a comparison between the flow rate based on the calculated velocity and the flow rate based on the calculated throttle valve. At 614, the method includes storing the calculated target channel calibration value.

[0057] The above-described system and method explain the operation of the flow control valve of the flow distribution channel in alternative control modes including a flow verification control mode and a flow ratio control mode. With this configuration, functionality can be improved while maintaining or reducing the material cost of the manufacturing hardware.

[0058] Furthermore, the efficiency of process control in individual reaction chambers is also improved. The MFC of each process chamber can execute the flow verification routine within a significantly shortened time frame. This efficiency is achieved by shortening the distance and flight time in the flow control within the system. This accelerated process not only saves time but also leads to an improvement in the overall throughput of semiconductor manufacturing.

[0059] According to this configuration, the MFC flow verification routine can also be executed in a parallel manner rather than a serial manner. This parallel processing significantly shortens the period required for tool qualification and chamber matching. By streamlining these processes, the time taken for setup and adjustment is reduced, improving the productivity of semiconductor manufacturing operations.

[0060] Furthermore, this configuration enables on-site verification of the MFC and allows for monitoring of long-term reproducibility and drift. In this on-site verification process implemented through the flow path of the flow rate ratio control, by quickly identifying and correcting deviations from the desired flow rate parameters, the reliability and accuracy of flow rate control can be maintained over a long period, and the manufacturing quality level can be maintained at a high level.

[0061] FIG. 8 is a perspective view of an example configuration of the flow rate ratio control system of FIG. 1. Four flow path configurations are shown, and flow path N is disposed between flow paths B and C, which are the hybrid distribution flow paths 14C described above. The other components are labeled in the same manner as in FIG. 1. When the sensor is an integrated package (e.g., TM1, PM1), a single lead wire indicates the package in which the sensor is housed. It will be understood that the mixing manifold 16 includes VM1, and these components are also indicated by a single lead wire. In FIG. 8, four flow paths are depicted, but it will be understood that additional flow paths may be added or fewer numbers of flow paths (more than two) may be utilized. Further, in the illustrated embodiment, flow rate control valves are shown for all of the distribution flow paths 14, but in some configurations, the flow rate control valves may be omitted from the distribution flow paths (i.e., so-called “open flow paths”), while in other cases, a plurality of other distribution flow paths may be controlled by flow rate control valves.

[0062] FIG. 9 is a partial cross-sectional view taken along the dotted line in FIG. 8 of the configuration example of the flow rate ratio control system of FIG. 8. In this figure, the positions of the internal volumes VM1, VM2, VM3, and the flow rate limiter RM and the position of the measured temperature sensor TM2 are shown.

[0063] FIG. 10 is an end view of the configuration example of the flow rate ratio control system of FIG. 8 as seen from the same perspective as FIG. 9. The cover of the hybrid distribution flow path 14C has been removed. In this figure, the positions of the measurement sensors PM2, TM3, and PM3, TM4 can be confirmed.

[0064] As shown in FIGS. 9 and 10, the isolation valve IV5 is disposed immediately upstream of the hybrid distribution flow path 14C, and the isolation valve IV6 is disposed immediately downstream of the same flow path 14C, thereby controlling the flow of fluid within the hybrid distribution flow path 14C. As shown in FIG. 9, the upstream isolation valve IV5 controls the fluid flow rate from the upstream reference volume VM1 of the downstream manifold 16 to the hybrid distribution flow path 14C.

[0065] In a housing compartment containing a hybrid distribution channel 14C, a cylindrical housing including a flow control valve CV3 integrated within a flow-path-specific flow control device 13 includes a first internal volume VM2, measurement temperature sensors TM2 and TM3, and an upstream measurement pressure sensor PM2. Another component set including a downstream measurement pressure sensor PM3, a downstream measurement temperature sensor TM4, and a second internal volume VM3 is housed within another cylindrical housing disposed adjacent to the cylindrical housing containing the first internal volume VM2. These cylindrical housings are disposed in proximity to each other, thereby increasing space utilization.

[0066] The control device 22 is physically attached to the hybrid distribution channel 14C and establishes a direct data communication link with the flow-path-specific flow control device 13 and each sensor and valve (isolation valves IV5, IV6), pressure sensors PM2, PM3, temperature sensors TM2, TM3, TM4, and flow restrictor RM, thereby reducing data transmission latency. This is advantageous for applications where fluid dynamics are important and accurate real-time monitoring and adjustment are required.

[0067] FIG. 11 schematically shows a non-limiting embodiment of a computing system 700 that can implement one or more of the methods and processes described above. The computing system 700 is shown in a simplified form. The computing system 700 can embody the control device system 10 described above and shown in FIGS. 1 and 8-10. The components of the computing system 700 can be included in one or more personal computers, server computers, tablet computers, home entertainment computers, network computing devices, video game devices, mobile computing devices, mobile communication devices (e.g., smartphones), and / or other computing devices, as well as wearable computing devices such as smartwatches and head-mounted augmented reality devices.

[0068] Computing system 700 includes a processing circuit 702, a volatile memory 704, and a non-volatile storage device 706. Computing system 700 may optionally include a display subsystem 708, an input subsystem 710, a communication subsystem 712, and / or other components not shown in FIG. 11.

[0069] The processing circuit generally includes one or more logical processors, and a logical processor is a physical device configured to execute instructions. For example, a logical processor may be configured to execute instructions that are part of one or more applications, programs, routines, libraries, objects, components, data structures, or other logical structures. Such instructions may be implemented to perform a task, implement a data type, transform the state of one or more components, achieve a technical effect, or achieve other desirable results.

[0070] A logical processor may include one or more physical processors configured to execute software instructions. Additionally or alternatively, a logical processor may include one or more hardware logic circuits or firmware devices configured to execute hardware-implemented logic or firmware instructions. The processor of processing circuit 702 may be single-core or multi-core, and the instructions executed therein may be configured for sequential, parallel, and / or distributed processing. The individual components of the processing circuit may optionally be distributed across two or more separate devices, which may be located remotely and / or configured for cooperative processing. For example, aspects of the computing system disclosed herein may be virtualized and executed by remotely accessible network computing devices configured in a cloud computing configuration. In such cases, it is understood that these virtualized aspects may be executed on different physical logic processors of different machines. The different physical logic processors of these different machines are understood to be encompassed by processing circuit 702.

[0071] The non-volatile memory device 706 includes one or more physical devices configured to hold instructions executable by the processing circuit for implementing the methods and processes described herein. When such methods and processes are implemented, the state of the non-volatile memory device 706 may change. For example, it may change to hold different data.

[0072] The non-volatile memory device 706 may include a removable and / or built-in physical device. The non-volatile memory device 706 may include optical memory, semiconductor memory, and / or magnetic memory, or other mass storage device technologies. The non-volatile memory device 706 may include non-volatile, dynamic, static, read / write, read-only, sequential access, location-specifiable, file-specifiable, and / or content-specifiable devices. It will be understood that the non-volatile memory device 706 is configured to hold instructions even when power to the non-volatile memory device 706 is interrupted.

[0073] The volatile memory 704 may include a physical device including random access memory. The volatile memory 704 is typically utilized by the processing circuit 702 to temporarily store information during the processing of software instructions. It will be understood that when power is removed from the volatile memory 704, the volatile memory 704 typically ceases to hold instructions.

[0074] Aspects of the processing circuit 702, the volatile memory 704, and the non-volatile memory device 706 may be integrated into one or more hardware logic components. Such hardware logic components include, for example, field programmable gate arrays (FPGAs), program and application specific integrated circuits (PASIC / ASICs), program and application specific standard products (PSSP / ASSPs), system on chips (SOCs), and complex programmable logic devices (CPLDs).

[0075] The terms "module", "program", and "engine" are used when describing aspects of computing system 700 that are typically implemented in software by a processor to execute a particular function using portions of volatile memory. This function includes conversion processing that specially configures the processor to execute the function. Thus, a module, program, or engine may be instantiated via processing circuitry 702 that uses a portion of volatile memory 704 to execute instructions held in non-volatile storage 706. It will be understood that different modules, programs, and / or engines may be instantiated from the same application, service, code block, object, library, routine, API, function, etc. Similarly, the same module, program, and / or engine may be instantiated by different applications, services, code blocks, objects, routines, APIs, functions, etc. The terms "module", "program", and "engine" may include individual files or groups such as executable files, data files, libraries, drivers, scripts, database records, etc.

[0076] When display subsystem 708 is included, it can be used to present a visual representation of data held in non-volatile storage 706. The visual representation can take the form of a graphical user interface (GUI). When the methods and processes described herein change data held by a non-volatile storage device, thereby transforming the state of the non-volatile storage device, the state of display subsystem 708 can be transformed as well to visually represent the underlying data change. Display subsystem 708 can include one or more display devices that utilize virtually any type of technology. Such display devices can be combined with processing circuitry 702, volatile memory 704, and / or non-volatile storage 706 within a shared housing, or such display devices can be external display devices.

[0077] The input subsystem 710 may be configured or connected to interface with one or more user input devices such as a keyboard, mouse, touch screen, camera, microphone, etc.

[0078] When a communication subsystem 712 is included, it can be configured to communicatively couple the various computing devices described herein to each other and to other devices. The communication subsystem 712 may include wired and / or wireless communication devices compatible with one or more different communication protocols. By way of non-limiting example, the communication subsystem may be configured for communication via a wired or wireless local area network, wide area network, broadband cellular network, etc. In some embodiments, the communication subsystem may enable the computing system 700 to send and receive messages to and from other devices via a network such as the Internet.

[0079] As used herein, “and / or” is defined as inclusive or ∨ and is specified by the following truth table.

[0080]

Table 1

[0081] In the present disclosure, when terms such as “comprising,” “including,” “having,” “containing,” etc. and their synonyms are used, these terms are intended to be used in an inclusive sense, similar to the term “consisting of,” without excluding additional elements or other elements.

[0082] The configurations and / or approaches described herein are exemplary, and it is understood that these specific embodiments or examples should not be considered in a limiting sense. This is because numerous variations are possible. The specific routines or methods described herein may represent one or more of any number of processing strategies. As such, the various acts illustrated and / or described may be performed in the order illustrated and / or described, in a different order, in parallel, or omitted. Similarly, the order of the above-described processing may be changed. As used herein, the phrase "and / or" means any one or all of a plurality of possibilities.

[0083] The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various processes, systems, configurations, and other features, functions, acts, and / or characteristics disclosed herein, as well as any equivalents thereof.

Claims

1. A flow rate ratio control system, comprising: an inlet configured to receive a total inlet fluid flow rate; a plurality of distribution channels fluidly connected to the inlet and arranged in parallel in a branched flow channel downstream of the inlet, each of the plurality of distribution channels comprising a respective valve and being configured to convey a respective portion of the total inlet fluid flow rate, the plurality of distribution channels including a hybrid distribution channel; a control device operably coupled to each of the plurality of distribution channels and configured to selectively operate in an alternative control mode including a flow rate verification control mode and a flow rate ratio control mode; In the flow rate verification control mode, the control device: uses a measurement value from a mass flow meter in the hybrid distribution channel to perform a first pressure change rate test on a first target flow path extending from the inlet through a reference volume to the hybrid distribution channel, thereby calculating a calibration value of the reference volume; uses the calibration value of the reference volume to perform a second pressure change rate test on a second target flow path from the inlet through the reference volume to a target distribution channel, thereby verifying a flow rate value measured by a mass flow meter in the target distribution channel of the plurality of distribution channels other than the hybrid distribution channel, and thereby calculating a target flow path calibration value of the mass flow meter in the target distribution channel; is configured to calibrate the mass flow meter in the target distribution channel using the target flow path calibration value; In the flow rate ratio control mode, the control device is configured to control each of the plurality of distribution channels including the hybrid distribution channel according to a respective flow rate ratio set point of each distribution channel. A flow rate ratio control system.

2. To perform the first pressure change rate test, the control device: controls a valve along the branched flow channel to establish the first target flow path; establishes a controlled compression or decompression of the reference volume using a calibrated total inlet fluid flow rate having a first predetermined mass flow rate value; measures temperature changes and pressure changes in the hybrid distribution channel using a temperature sensor and a pressure sensor in the hybrid distribution channel, respectively, during the controlled compression or decompression. The flow rate ratio control system according to claim 1, configured to calculate a calibration value of the reference volume based on the measured temperature change, the measured pressure change, the first predetermined mass flow rate value, and the gas constant.

3. To perform verification of the flow rate value measured by the mass flow meter in the target distribution channel in the flow rate verification control mode, the control device further controls a valve along the branch channel to establish the second target channel only between the inlet and the target distribution channel, the second target channel including the reference volume, while the second target channel is established, establish a controlled compression or decompression of the reference volume using a calibrated total inlet fluid flow rate having a second predetermined mass flow rate value, during the controlled compression or decompression while the second target channel is established, measure pressure changes and temperature changes using the temperature sensor and the pressure sensor in the target distribution channel, calculate a rate-of-change based flow rate through the target distribution channel based on the measured pressure change, the measured temperature change, the calibration value of the reference volume, and the second predetermined mass flow rate value, configured to calculate a restrictor-based flow rate through the target distribution channel based on the restrictor dimensions of a restrictor in the target distribution channel and the second predetermined mass flow rate value, The target channel calibration value is calculated based on a comparison between the calculated rate-of-change based flow rate and the calculated restrictor-based flow rate. The flow rate ratio control system according to claim 2.

4. The control device is configured to measure the temperature change and the pressure change by measuring the initial pressure and the initial temperature, and the subsequent pressure and the subsequent temperature in the hybrid distribution channel as a result of the controlled compression or decompression, The calibration value of the reference volume is calculated using the ideal gas law, the measured initial pressure, the measured initial temperature, the measured subsequent pressure, the measured subsequent temperature, the gas constant, and the mass flow rate of the calibrated total inlet fluid flow rate. The flow rate ratio control system according to claim 2.

5. The inlet is formed upstream of the manifold. The control device according to claim 2, wherein the control device is configured to perform verification using, as the reference volume, an upstream reference volume provided in the manifold on the branch flow path upstream of a mass flow meter disposed downstream of the inlet and within the hybrid distribution flow path.

6. The flow rate ratio control system according to claim 5, wherein the manifold includes an upstream measurement pressure sensor and an upstream measurement temperature sensor that are located within the upstream reference volume and operably coupled to the control device.

7. The flow rate ratio control system according to claim 5, wherein the plurality of distribution flow paths include a high flow rate distribution flow path that branches from the manifold at a point upstream of the branch point of the hybrid distribution flow path and includes a downstream reference volume having isolation valves on the upstream side and the downstream side.

8. The flow rate ratio control system according to claim 1, wherein the reference volume is an intermediate reference volume provided on the branch flow path upstream of the mass flow meter disposed downstream of the inlet and within the hybrid distribution flow path.

9. The temperature sensor in the hybrid distribution flow path is a measurement temperature sensor located within the intermediate reference volume, The flow rate ratio control system according to claim 8, wherein the pressure sensor in the hybrid distribution flow path is a measurement pressure sensor located within the intermediate reference volume.

10. The flow rate ratio control system according to claim 9, wherein the measurement temperature sensor is one of a pair of measurement pressure sensors in the hybrid distribution flow path, and the measurement pressure sensor is one of a pair of measurement temperature sensors located on each side of a restrictor.

11. The inlet receives the total inlet fluid flow rate from one or more inlet flow paths each having a mass flow controller, In the flow rate verification control mode, the control device is further configured to verify a mass flow rate value measured by a target mass flow controller in a target inlet flow path using measurement values from a pressure sensor and a temperature sensor in the hybrid distribution flow path, calculate a target mass flow controller calibration value, and calibrate the mass flow controller in the target inlet flow path using the target mass flow controller calibration value. The flow rate ratio control system according to claim 1.

12. The hybrid distribution flow path includes, in this order in the downstream flow direction of the hybrid distribution flow path, one of each of the valves, a first internal volume, a measurement temperature sensor configured to measure the temperature of the first internal volume, an upstream measurement temperature sensor and an upstream measurement pressure sensor, a restrictor, a downstream measurement temperature sensor and a downstream measurement pressure sensor, and a second internal volume, and includes an array of a series of components including these, the flow rate ratio control system according to claim 1.

13. The accuracy of the upstream measurement pressure sensor and the downstream measurement pressure sensor is an accuracy value within ±0.1% of full scale (FS). The temperature coefficient of the upstream measurement temperature sensor and the downstream measurement temperature sensor is an accuracy value within ±0.02% of full scale / °C (FS / °C), the flow rate ratio control system according to claim 12.

14. The upstream measurement pressure sensor and the downstream measurement pressure sensor are MEMS (microelectromechanical system) vibrating type pressure sensors, the flow rate ratio control system according to claim 12.

15. The diameter of the flow path in the restrictor is less than 50 micrometers. The length of the flow path in the restrictor is greater than 10 millimeters and less than 50 millimeters, the flow rate ratio control system according to claim 12.

16. The flow rate ratio control system according to claim 1, further comprising an additional distribution flow path in the branch flow path downstream of the inlet, the additional distribution flow path being provided without a flow rate control valve and configured to convey each portion of the total inlet fluid flow rate.

17. The hybrid distribution flow path further includes a mass flow rate control device having a restrictor containing a ceramic material. The internal flow path of the restrictor is formed in the ceramic material, the flow rate ratio control system according to claim 1.

18. An inlet configured to receive a total inlet fluid flow rate, and a plurality of distribution flow paths fluidly connected to the inlet and arranged in parallel to a branch flow path downstream of the inlet, each of the plurality of distribution flow paths including a respective valve and configured to convey each portion of the total inlet fluid flow rate, and a flow rate ratio control method for use in a flow rate ratio controller including a plurality of distribution flow paths including the hybrid distribution flow path, Execute a flow rate verification control mode, and the execution includes For the first target flow path extending from the inlet through the reference volume to the hybrid distribution flow path, a first pressure change rate test is performed using the measured value from the mass flow meter in the hybrid distribution flow path, thereby calculating a calibration value for the reference volume. Verification of the flow rate value measured by the mass flow meter in the target distribution flow path of the plurality of distribution flow paths other than the hybrid distribution flow path is performed by executing a second pressure change rate test for the second target flow path from the inlet through the reference volume to the target distribution flow path using the calibration value of the reference volume, thereby calculating a target flow path calibration value for the mass flow meter in the target distribution flow path. Including calibrating the mass flow meter in the target distribution flow path using the target flow path calibration value. A flow rate ratio control method that executes a flow rate ratio control mode, in which each of the plurality of distribution flow paths including the hybrid distribution flow path is controlled according to the respective flow rate ratio set points of each distribution flow path.

19. The execution of the first pressure change rate test Controls the valve along the branch flow path to establish the first target flow path. Establishes a controlled compression or decompression of the reference volume using a calibrated total inlet fluid flow rate having a first predetermined mass flow rate value. During the controlled compression or decompression, measures the temperature change and pressure change in the hybrid distribution flow path using the temperature sensor and pressure sensor in the hybrid distribution flow path respectively. Includes calculating a calibration value for the reference volume based on the measured temperature change, the measured pressure change, the first predetermined mass flow rate value, and the gas constant. The execution of the verification of the flow rate value measured by the mass flow meter in the target distribution flow path in the flow rate verification control mode Controls the valve along the branch flow path to establish the second target flow path only between the inlet and the target distribution flow path, and the second target flow path includes the reference volume. Establishes a controlled compression or decompression of the reference volume using a calibrated total inlet fluid flow rate having a second predetermined mass flow rate value while the second target flow path is established. Measures the pressure change and temperature change using the temperature sensor and the pressure sensor in the target distribution flow path during the controlled compression or decompression while the second target flow path is established. Calculate a rate-of-change-based flow rate through the target distribution channel based on the measured pressure change, the measured temperature change, the calibration value of the reference volume, and the second predetermined mass flow rate value. Including calculating a restrictor-based flow rate through the target distribution channel based on the restrictor dimensions of a restrictor within the target distribution channel and the second predetermined mass flow rate value. The method for controlling a flow rate ratio according to claim 18, wherein the target flow channel calibration value is calculated based on a comparison between the calculated rate-of-change-based flow rate and the calculated restrictor-based flow rate. [

20. ] A flow rate ratio control system, comprising: An inlet configured to receive a total inlet fluid flow rate; A plurality of distribution channels fluidly connected to the inlet and arranged in parallel in a branch channel downstream of the inlet, each of the plurality of distribution channels being configured to convey a respective portion of the total inlet fluid flow rate, the plurality of distribution channels including a hybrid distribution channel; A control device operably coupled to the plurality of distribution channels and configured to selectively operate in an alternative control mode including a flow rate verification control mode and a flow rate ratio control mode. In the flow rate verification control mode, the control device: Controls a valve along the branch channel to establish a first target flow channel between the inlet and only the hybrid distribution channel, the first target flow channel including a reference volume; Establishes a controlled compression or decompression of the reference volume; Measures a first temperature change and a first pressure change within the hybrid distribution channel during the controlled compression or decompression; Calculates a calibration value of the reference volume based on at least a portion of the measured first temperature change and the measured first pressure change; Controls a valve along the branch channel to establish a second target flow channel between the inlet and only a target distribution channel including a target mass flow meter, the second target flow channel including the reference volume; Establishes a controlled compression or decompression of the reference volume while the second target flow channel is established; Measures a second pressure change and a second temperature change using a temperature sensor and a pressure sensor within the target distribution channel during the controlled compression or decompression while the second target flow channel is established; Calculates a rate-of-change-based flow rate through the target distribution channel based on at least a portion of the measured second pressure change and the measured second temperature change. Calculate a restrictor-based flow rate through the target distribution channel based on at least a portion of the measured second pressure change and the second temperature change, Calculate a target flow channel correction value based on a comparison between the calculated change rate-based flow rate and the calculated restrictor-based flow rate, configured to correct the target distribution channel using the target flow channel correction value, In the flow rate ratio control mode, the control device is configured to control each of the plurality of distribution channels including the hybrid distribution channel and the target distribution channel having the calibrated mass flow meter according to the respective flow rate ratio set points of each distribution channel, a flow rate ratio control system.

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