An algorithm for a one-in-three gas flow divider

Abstract

The application discloses a one-to-three type gas shunt algorithm, wherein the precondition of the shunt algorithm is that the shunt 3 branches are three MFM+ control valves, MFM is a gas mass flow measurer, the control valve can change the gas flow of a single path, the shunt controls the gas proportion of each path, for example, 20%, which means that the gas flow of the path is 20% of the total inlet gas amount; the shunt opens the three-channel valve to the maximum process opening degree at the initial time, which is a self-defined value, for example, 80% of the physical maximum opening degree of the valve; and the specific method of the algorithm is as follows: S1, when the shunt receives the shunted proportion, the three different proportions are R1>=R2>=R3; S2, the relatively small two paths, R2 and R3, are found, and the proportion of the third path is controlled through PID to reach the target value R2; and S3, in the process of S2, R1 and R3 are always changing, R 2p -R 3p The device solves the problem of poor practicability at present.

Description

Technical Field

[0001] This invention belongs to the field of gas splitter technology, specifically relating to an algorithm for a one-to-three type gas splitter. Background Technology

[0002] Gas splitting is becoming increasingly common in modern semiconductor devices because semiconductors are getting bigger and bigger, and more gas partitions are needed to achieve more precise control over micromachining.

[0003] Gas splitters divide a gas mixture from a single gas path into two or more paths. The algorithm for a one-to-two splitter is relatively simple, requiring only a PID controller to manage the proportion of one branch. However, a one-to-three splitter is more complex because it involves controlling two branches, and these branches can interfere with each other during control, leading to prolonged response times or even non-convergence, thus reducing its practicality. This phenomenon has become a problem urgently needing to be solved by those in the field. Summary of the Invention

[0004] The purpose of this invention is to provide an algorithm for a one-to-three gas splitter for existing material collection devices, in order to solve the problems mentioned in the background art.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: an algorithm for a one-to-three gas splitter, including the premise that the three branches of the splitter are three MFM+control valves. MFM is a gas mass flow meter, the control valve can change the gas flow of a single branch, and the splitter controls the gas ratio of each branch, for example, 20%, which means that the gas flow of that branch is 20% of the total intake volume.

[0006] The present invention further explains that the specific method of the algorithm is as follows:

[0007] S1. When the current shunt receives a certain proportion of current, there are three different ratios: R1≥R2≥R3;

[0008] S2. Find the two relatively smaller values, R2 and R3, and use PID control to adjust the ratio of the third channel to reach the target value R2.

[0009] S3. During process S2, R1 and R3 are constantly changing. Ignoring R1, calculate R. 2p -R 3p The ratio is controlled by PID to adjust the difference between the second and third channels, so that it reaches the target value R2-R3;

[0010] S4. When R 2p =R2,R 2p -R 3p When R = R2 - R3, R 1p It must equal R1. At this point, the three-channel current splitting is complete.

[0011] S5. When the given ratio of the split changes, if R1 is still the largest, continue with the above splitting method.

[0012] S6. If the new ratio is changed to R2 or R3 as the maximum, first open the valve of the maximum channel to the maximum process opening, and then control the ratio using the above method.

[0013] The present invention further explains that, initially, the valves of the three channels of the diverter are all opened to the maximum process opening degree, which is a custom value, such as 80% of the physical maximum opening degree of the valve.

[0014] The present invention further includes a gas control valve adjustment module, which includes a total flow rate calibration module, a gas volume calibration module, an idle quantity calculation module, and a gas control valve adjustment module. The total flow rate calibration module is electrically connected to the gas volume calibration module and the idle quantity calculation module, and the gas quantity statistics module is electrically connected to the total flow rate calibration module.

[0015] The present invention further explains that the total flow rate calibration module is used to count the gas volume that needs to rely on distributed storage, the gas volume calibration module is used to verify the space occupied by each gas control valve, the idle amount calculation module is used to determine whether the current gas control valve flow is idle, and the gas control valve adjustment module is used to allocate the flow rate and occupied space of the gas control valve of each gas source.

[0016] The present invention further explains that the specific method by which the gas control valve allocation module calculates the optimal solution for the gas control valve flow rate of the distributed backup determination module is as follows:

[0017] S5. The total space W required by all distributed backup decision modules of the node where the new gas is generated, and the total space occupied by all gas control valves at the mutual diversion ends of this area is q.

[0018] This invention further illustrates that when At this time, the gas control valve is idle, and excess gas control valves are stopped from working. At this time, the gas control valve is working normally. At this time, the gas control valves are busy. First, ensure that each distributed node has a certain flow of gas control valves for basic storage work, and then distribute the remaining gas control valves.

[0019] The present invention further explains that in step S5 above, the optimal solution for the gas control valve flow rate of a certain distributed backup determination module is: based on the gas control valve flow rate on all mutually split ends, the total distributed node flow rate of newly generated gas, the gas control valve flow rate required for the operation of a single distributed node, and the total amount of newly generated gas by a certain distributed node, the distribution is made.

[0020] Compared with the prior art, the beneficial effects achieved by the present invention are: the present invention does not affect each other when controlling two branches, has a short response time, and only requires a PID to control the proportion of one branch to achieve the one-to-three flow method. Attached Figure Description

[0021] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0022] Figure 1 This is a flowchart illustrating the present invention. Detailed Implementation

[0023] The following detailed, non-limiting description of the technical solution of the present invention, in conjunction with preferred embodiments and accompanying drawings, is provided. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0024] Please see Figure 1 The present invention provides a technical solution: an algorithm for a one-to-three gas splitter, including the premise that the three branches of the splitter are three MFMs + control valves. MFM is a gas mass flow meter, the control valve can change the gas flow of a single branch, and the splitter controls the gas ratio of each branch, such as 20%, which means that the gas flow of that branch is 20% of the total intake.

[0025] The specific method of this algorithm is as follows:

[0026] S1. When the current shunt receives a certain proportion of current, there are three different ratios: R1≥R2≥R3;

[0027] S2. Find the two relatively smaller values, R2 and R3, and use PID control to adjust the ratio of the third channel to reach the target value R2.

[0028] S3. During process S2, R1 and R3 are constantly changing. Ignoring R1, calculate R. 2p -R 3pThe ratio is controlled by PID to adjust the difference between the second and third channels, so that it reaches the target value R2-R3;

[0029] S4. When R 2p =R2,R 2p -R 3p When R = R2 - R3, R 1p It must equal R1. At this point, the three-channel current splitting is complete.

[0030] S5. When the given ratio of the split changes, if R1 is still the largest, continue with the above splitting method.

[0031] S6. If the new ratio is changed to R2 or R3 as the maximum, first open the valve of the maximum channel to the maximum process opening, and then control the ratio using the above method.

[0032] Initially, the valves of all three channels of the distributor are opened to the maximum process opening, which is a custom value, such as 80% of the valve's physical maximum opening.

[0033] It also includes a gas control valve adjustment module, which includes a total flow rate calibration module, a gas volume calibration module, an idle quantity calculation module, and a gas control valve adjustment module. The total flow rate calibration module is electrically connected to the gas volume calibration module and the idle quantity calculation module, and the gas quantity statistics module is electrically connected to the total flow rate calibration module.

[0034] The total flow rate verification module is used to count the gas volume that needs to rely on distributed storage. The gas volume verification module is used to verify and confirm the space occupied by each gas control valve. The idle amount calculation module is used to determine whether the current gas control valve flow is idle. The gas control valve adjustment module is used to allocate the flow rate and occupied space of the gas control valve of each gas source.

[0035] The specific method by which the gas control valve allocation module calculates the optimal solution for the gas control valve flow rate of the distributed backup judgment module is as follows:

[0036] S5. The total space W required by all distributed backup decision modules of the node where the new gas is generated, and the total space occupied by all gas control valves at the mutual diversion ends of this area is q.

[0037] when At this time, the gas control valve is idle, and excess gas control valves are stopped from working. At this time, the gas control valve is working normally. At this time, the gas control valves are busy. First, we will ensure that each distributed node has a certain flow of gas control valves to perform basic storage work, and then distribute the remaining gas control valves.

[0038] In step S5 above, the optimal solution for the gas control valve flow rate of a certain distributed backup determination module is as follows: the gas control valve flow rate on all the mutual split ends, the total distributed node flow rate of newly generated gas, the gas control valve flow rate required for the operation of a single distributed node, and the total amount of newly generated gas by a certain distributed node are allocated.

[0039] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features, and these modifications or substitutions 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. An algorithm for a one-to-three gas splitter, characterized in that: The premise of the aforementioned splitter algorithm is that each of the three branches of the splitter is equipped with an MFM and a control valve. The MFM is a gas mass flow meter, the control valve changes the gas flow rate of a single branch, and the splitter controls the gas ratio of each branch. The specific method of this algorithm is as follows: S1. When the shunt receives a shunt, there are 3 different ratios: ; S2. Find the two relatively smaller paths. , The third channel's proportional gain is controlled by a PID controller to achieve the target value. ; S3, during the process of S2 , It's constantly changing, don't consider it. ,calculate The ratio is controlled by PID to adjust the difference between the second and third channels, so that it reaches the target value. ; S4, when , hour, It must equal At this point, the three-channel traffic splitting is complete; S5. When the given ratio of the diversion changes, if It's still the largest, so we'll continue with the above division method; S6. If the new ratio is changed to or When the maximum is reached, first open the valve of the largest channel to the maximum process opening, and then control the ratio using the method described above.

2. The algorithm for a one-to-three gas splitter according to claim 1, characterized in that: Initially, the valves of all three channels of the distributor are opened to the maximum process opening, which is a user-defined value.

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