JP6215120B2 - Flow control device inspection method, flow control device inspection system, and flow control device inspection system program - Google Patents

Description

  The present invention relates to an inspection method for a flow rate control device that controls the flow rate of a fluid such as a gas or a liquid in a semiconductor manufacturing process or the like, an inspection system for a flow rate control device, and an inspection system program for the flow rate control device.

  For example, in Patent Document 1, when inspecting whether or not the flow rate measured by the flow rate control device shows a correct value, the flow rate that can significantly reduce the waiting time until the inspection is started and the time required for the inspection itself. A control device inspection method is shown.

  This inspection method is provided in the order of a thermal flow control device to be inspected from upstream and a pressure flow control device to be a reference with respect to the flow path. Further, the valve opening of the thermal flow control device is fully opened, and the valve opening of the pressure flow control device is controlled based on the deviation between the set flow rate and the actual flow rate measured by the pressure flow control device. . As described above, the thermal flow control device to be inspected is brought into the non-flow control state, and the pressure flow control device as the reference is put into the flow control state, and each actual flow rate measured by each flow control device is compared. Thus, it is inspected whether or not the actually measured flow rate of the thermal flow control device is correct.

  By the way, in a semiconductor manufacturing process or the like, not only can the flow control device be inspected in a short time, but it is also required to further improve the inspection accuracy particularly in a low flow rate region.

WO2008 / 069227 publication

  The present invention has been made in view of the above-described problems, and an inspection method for a flow rate control device that can further improve inspection accuracy in a low flow rate region while shortening waiting time and actual inspection time. An object of the present invention is to provide a flow control device inspection system and a flow control device inspection system program.

  That is, the inspection method for the flow rate control device of the present invention includes a first valve, a first flow rate sensor that measures the flow rate of fluid, and a first valve control unit that controls the opening degree of the first valve. The flow rate control device to be used and the second flow rate sensor to be a reference are used, and the flow rate control device to be inspected from the upstream side in series on the flow path through which the fluid flows and the second flow rate sensor to be the reference in series. In the inspection method of the flow rate control device to be inspected provided in, until the flow rate of the fluid flowing through the flow path becomes a predetermined flow rate, or until the pressure of the fluid flowing through the flow path becomes a predetermined pressure, An initial flow rate control step for controlling the flow rate of the fluid flowing through the flow path based on a deviation between the set flow rate and the second actual flow rate measured by the second flow rate sensor, and the flow rate of the fluid flowing through the flow path is a predetermined flow rate. Or before After the pressure of the fluid flowing in the flow path reaches a predetermined pressure, the first valve is opened based on a deviation between a set flow rate in the first valve control unit and a first actually measured flow rate measured by the first flow rate sensor. A flow rate control switching step for controlling the flow rate of the fluid flowing in the flow path by controlling the degree of flow, and a flow rate of the fluid flowing in the flow path being controlled based on a deviation between the set flow rate and the first actually measured flow rate And an inspection step for inspecting the first actual flow rate measured by the flow rate control device to be inspected based on the second actual flow rate measured by the second flow rate sensor serving as the reference. .

  Here, “inspecting the first actual flow rate measured by the flow rate control device to be inspected based on the second actual flow rate measured by the second flow rate sensor serving as the reference” means the first actual flow rate. Is a concept that includes verifying whether the second measured flow rate is correct with reference to the second measured flow rate and calibrating the first measured flow rate so as to be the second measured flow rate.

  In this case, in the initial flow rate control step, the flow rate is determined based on the set flow rate and the deviation between the second actual flow rate measured by the second flow rate sensor downstream of the flow rate control device to be verified. Since the control is performed, it is possible to realize the flow rate and pressure which are the premise of the inspection in a short time before the inspection is started by the reliable second flow rate sensor.

  Further, in the flow rate control switching step, the flow rate is controlled so that the first valve control unit controls the opening degree of the first valve based on a deviation between a set flow rate and a first actually measured flow rate measured by the first flow rate sensor. By switching the control, the flow rate can be controlled by the first valve in the vicinity of the first flow rate sensor where the first actually measured flow rate to be inspected is measured. Therefore, the stability of the first actually measured flow rate measured by the first flow rate sensor can be improved. Further, since the inspection can be performed while reproducing the state in which the flow rate control device to be inspected is actually used, an inspection that is more realistic can be performed.

  As a specific embodiment to improve the stability of the flow rate in the flow rate control device to be inspected at the time of inspection and the reproducibility of the actual flow rate control state while shortening the waiting time until the start of the inspection A reference flow control device comprising a second valve, a reference second flow rate sensor, and a second valve control unit for controlling the opening of the second valve, downstream of the flow control device to be inspected In the initial flow rate control step, the first valve control unit of the flow rate control device to be inspected is kept constant in the opening degree of the first valve and becomes the inspection target. The flow control device is set in a non-flow control state, a set flow rate is given to the reference flow control device, and a set flow rate and a second actual flow rate measured by the second flow sensor are supplied to the second valve control unit. To deviation Accordingly, the opening degree of the second valve is controlled to set the reference flow control device to a flow control state, and in the flow control switching step, the flow control device to be inspected is given a set flow rate, The first valve control unit controls the opening degree of the first valve based on the deviation between the set flow rate and the first actually measured flow rate measured by the first flow rate sensor, thereby controlling the flow rate control device to be inspected. And the second valve control unit of the reference flow control device keeps the opening degree of the second valve constant so that the reference flow control device is in a non-flow control state. Can be mentioned

  In such a case, in the initial flow rate control step, the flow rate control device to be inspected is in a flow non-control state, and the first valve is maintained at a constant opening, so The pressure required to start the determination in the determination step is increased by increasing the pressure of the fluid flowing into the flow path (dead volume) between the flow control device to be inspected and the reference flow control device. Preconditions such as the flow rate can be adjusted in a short time, and the waiting time until the start of verification and calibration can be made very short.

  In the flow control switching step, the flow control device to be inspected is set in a flow control state, and the reference flow control device is switched to a flow non-control state in which the opening of the second valve is kept constant, The flow rate is controlled by the first valve in the vicinity of the first flow rate sensor where the first actually measured flow rate to be inspected is measured. Therefore, the stability of the first actually measured flow rate measured by the first flow rate sensor can be improved. Further, since the inspection can be performed while reproducing the state in which the flow rate control device to be inspected is actually used, an inspection that is more realistic can be performed.

  Even when the set flow rate is set to a low flow rate, the first actually measured flow rate can be stabilized, so that the inspection accuracy in the determination step can be made higher than before. In addition, since the second valve of the reference flow control device on the downstream side is maintained at a constant opening, it can be released when there is excessive pressure, further improving the flow rate stability during inspection. The accuracy of inspection can be improved.

  Increase the amount per unit time of the fluid flowing into the flow path (dead volume) between the flow control device to be inspected and the reference flow control device to obtain the required pressure in a short time In order to shorten the waiting time until the start of inspection as much as possible, in the initial flow rate control step, the first valve opening of the first valve control unit of the flow rate control device to be inspected is fully opened. Anything can be used as long as it is allowed to.

  In order to make the second valve of the reference flow control device less likely to affect the inspection and improve the inspection accuracy during the inspection, the reference flow control is performed in the switching step. What is necessary is just to make it make the said 2nd valve control part of an apparatus make the opening degree of a said 2nd valve fully open.

  In the inspection step, a plurality of different values are set as the set flow rate so that evaluation can be performed over the entire range measurable as the first actually measured flow rate, and more accurate determination is possible. It is preferable that the first actual flow rate measured by the flow rate control device to be inspected is inspected based on the second actual flow rate measured by the reference flow rate control device.

  In order to stabilize the flow rate control operation of the flow rate producing device to be inspected and perform the inspection in the low flow rate region with higher accuracy, the pressure of the fluid flowing in the flow path is made constant in the arranging step. A pressure control device for controlling the flow rate may be further provided upstream of the flow rate control device to be inspected or between the flow rate control device to be inspected and the reference flow rate control device.

  As a specific embodiment in which each flow rate control device performs flow rate measurement with a different measurement principle and more accurately inspects the flow rate control device to be inspected, the first flow rate of the flow rate control device to be inspected The sensor measures the flow rate based on the temperature of the fluid, and the second flow rate sensor of the reference flow control device measures the flow rate based on the pressure of the fluid.

  As a specific embodiment for easily determining the quality of the flow control device to be inspected, the inspection step includes a first actually measured flow rate measured by the flow control device to be inspected, One including a verification step for verifying whether or not the second actually measured flow rate measured by the reference flow rate control device is within a predetermined range is raised.

  As a specific embodiment for enabling the flow rate control device to be inspected to output substantially the same actual measured flow rate as the reference flow rate control device, the inspection step is the flow rate to be inspected. What is necessary is just to include a calibration step for calibrating the first actually measured flow rate measured by the control device based on the second actually measured flow rate measured by the reference flow rate control device.

  As a specific embodiment for enabling each effect of the present invention to be taught only by the first valve of the flow rate control device to be inspected, the flow rate to be inspected in the initial flow rate control step is as follows. The first valve control unit of the control device controls the opening degree of the first valve based on a deviation between a set flow rate and a second actually measured flow rate measured by the second flow rate sensor serving as the reference, and the flow rate control switching In the step, the opening degree of the first valve is controlled based on a deviation between a set flow rate and a first actually measured flow rate measured by the first flow rate sensor in the first valve control unit of the flow rate control device to be inspected. To be made.

  Desirable specific embodiments of the inspection system for the flow rate control device of the present invention include a first valve, a first flow rate sensor for measuring the flow rate of fluid, and a first valve for controlling the opening degree of the first valve. An inspection system for a flow control device used for inspection of a flow control device to be inspected provided with a control unit, wherein a reference is provided on a downstream side of the flow control device to be inspected on a flow path through which the flow rate flows. Measured with the set flow rate and the second flow rate sensor until the flow rate of the fluid flowing through the flow channel becomes a predetermined flow rate or until the pressure of the fluid flowing through the flow channel becomes a predetermined pressure. A command output unit for outputting a command for controlling the flow rate of the fluid flowing through the flow path based on a deviation from the second actually measured flow rate, and the flow rate of the fluid flowing through the flow path becomes a predetermined flow rate, or Flow through the flow path After the pressure reaches a predetermined pressure, the command output unit outputs a setting command signal indicating a set flow rate to the flow rate control device to be inspected, and the set flow rate and the first flow rate to the first valve control unit. A command output from the command output unit is switched so as to control the flow rate of the fluid flowing through the flow path by controlling the opening degree of the first valve based on the deviation of the first actual flow rate measured by one flow sensor. In a state where the flow rate control switching unit and the flow rate control device to be inspected are in flow control, the first actually measured flow rate measured by the flow rate control device to be inspected is measured by the second flow rate sensor to be the reference. And an inspection unit for inspecting based on the second actually measured flow rate.

  To add the function and effect of the present invention to an inspection system for an existing flow control device, the first valve, the first flow sensor for measuring the flow rate of the fluid, and the opening of the first valve are controlled. This is used for the inspection of the flow rate control device to be inspected with the first valve control unit, and is a reference provided on the downstream side of the flow rate control device to be inspected on the flow path through which the flow rate flows. A program used in an inspection system for a flow rate control device having two flow rate sensors, wherein the flow rate of the fluid flowing through the flow path becomes a predetermined flow rate, or the pressure of the fluid flowing through the flow path becomes a predetermined pressure A command output unit for outputting a command for controlling the flow rate of the fluid flowing through the flow path based on a deviation between a set flow rate and a second actual flow rate measured by the second flow rate sensor; and a fluid flowing through the flow path Flow rate After the predetermined flow rate is reached or the pressure of the fluid flowing through the flow path becomes a predetermined pressure, the command output unit outputs a setting command signal indicating a set flow rate to the flow rate control device to be inspected. The first valve control unit controls the flow rate of the fluid flowing through the flow path by controlling the opening of the first valve based on the deviation between the set flow rate and the first actual flow rate measured by the first flow rate sensor. In a state where the flow rate control switching unit that switches the command output by the command output unit and the flow rate control device that is the inspection target are in flow control, the measurement is performed by the flow rate control device that is the inspection target. For an inspection system for a flow control device, which causes a computer to function as an inspection unit that inspects an actual measurement flow rate based on a second actual flow rate measured by the reference flow control device. It may be used program.

  The inspection system program may be an inspection system program recording medium recorded on a recording medium such as a CD, a DVD, or a flash memory.

  As described above, according to the inspection method for the flow rate control device of the present invention, the flow rate control is initially performed by the second actually measured flow rate measured by the second flow rate sensor serving as the reference on the downstream side, and the preconditions for the inspection are prepared. Since it is configured to switch to flow control at the first actual flow rate measured by the first flow sensor of the flow control device to be inspected from the middle, at the time of inspection of the flow control device to be inspected Flow control is performed by the first valve located near the first flow rate sensor, and the first actually measured flow rate to be measured can be stabilized even in a low flow rate region, and the inspection accuracy can be improved as compared with the conventional one.

The schematic diagram which shows the whole inspection system of the flow control apparatus which concerns on one Embodiment of this invention. The schematic diagram which shows the inspection system of the flow control apparatus in the initial state in the embodiment. The schematic diagram which shows the test | inspection system of the flow control apparatus after the test start conditions in the same embodiment have been prepared. The flowchart which shows the operation | movement at the time of the test | inspection of the test | inspection system of the flow control apparatus in the embodiment. The schematic diagram which shows the inspection system of the flow control apparatus in the initial state in another embodiment of this invention. The schematic diagram which shows the test | inspection system of the flow control apparatus after the test start conditions in another embodiment of this invention were prepared.

  An inspection system for a flow control device according to an embodiment of the present invention will be described with reference to FIGS.

As shown in FIG. 1, the inspection system A of the flow control device of the present embodiment is, for example, an inspection of a flow control device that performs flow control of various gases supplied to the process chamber C as part of the semiconductor manufacturing apparatus P. It is used for. Specifically, the semiconductor manufacturing apparatus P includes gas supply lines 1a, 1b,... (Hereinafter collectively referred to as “gas supply line 1”) through which various semiconductor manufacturing gases such as process gas and etching gas flow. , A chamber line 2 and inspection lines 3a, 3b, and 3c (hereinafter collectively referred to as "inspection line 3") provided in parallel downstream from the junction where the gas supply line 1 merges, and gas supply The flow rate control devices 4a, 4b,... (Hereinafter collectively referred to as “flow rate control device 4 to be inspected”) provided on the line 1 and the reference provided on the inspection line 3 respectively. And the pressure control provided on the gas supply line 1 on the upstream side of the flow rate control device 4 to be inspected, and the flow rate control devices 5a, 5b, 5c (hereinafter collectively referred to as “reference flow rate control device 5”). Device 6 , 6b · · · (hereinafter collectively referred to as "pressure control device 6") and the first measured flow rate Q _C is the reference flow rate control device of the flow control device 4 each flow control device be inspected by a predetermined operation 5 and the second measured flow rate Q _S determines the information processing apparatus 7 whether the predetermined range by, those made comprises a. The flow rate control device inspection system 7 includes at least a reference flow rate control device 5 and an information processing device 7, and further includes a pressure control device 6 in this embodiment. In other words, the flow rate control device inspection system 7 does not include the flow rate control device 4 to be inspected.

  Hereinafter, each part will be described in detail.

  The gas supply line 1 is connected to a gas cylinder (not shown) that stores various gases on the upstream side, and the downstream side is joined at the joining portion 1x, so that a single gas or a mixed gas can be supplied to the process chamber C. It is configured.

  The chamber line 2 is a line for supplying various gases flowing from the gas supply line 1 to the process chamber C. At the time of inspection, a valve 2V for preventing various gases from flowing through the chamber line 2 is provided. The valve 2V is controlled to be opened and closed by the information processing device 7.

  A plurality of (three in this embodiment) inspection lines 3 are provided in parallel on the downstream side of the junction 1x. Each inspection line 3 is provided with a reference flow rate control device 5 having a different flow rate range that can be inspected, that is, a different flow rate control range. Specifically, a flow rate control device 5a serving as a reference capable of measuring (controlling) a flow rate of 20 to 200 SCCM is arranged in the inspection line 3a, and a flow rate of 200 to 2,000 SCCM is measured in the inspection line 3b. A flow control device 5b serving as a reference that can be (controlled) is disposed, and a flow control device 5c serving as a reference capable of measuring (controlling) a flow rate of 2,000 to 20,000 SCCM is disposed in the inspection line 3c. Valves 3Va, 3Vb, and 3Vc are provided on the upstream side of the reference flow rate control device 5. Further, a valve 3Vx is provided to prevent various gases from flowing through the inspection line 3 during non-inspection. These valves 3Va to 3Vc and 3Vx are controlled to be opened and closed by the information processing device 7.

In this embodiment, the flow rate control device 4 to be inspected is a thermal mass flow rate control device (thermal mass flow controller). Which is driven by a command signal from the outside, when given a set flow rate Q _R as the command signal controls the valve such that its set flow rate Q _R performs local feedback control inside In addition, depending on the content of the command signal, open loop control can be performed to fully open or close the valve. As shown in FIG. 2, the internal configuration includes a first internal flow path 40, a first flow rate sensor 41 for measuring the flow rate of the fluid flowing in the first internal flow path 40, and a first flow path as shown in FIG. For example, a first valve 42 provided on the downstream side of the flow sensor 41 and a first valve control unit 43 are provided. Each part will be described more specifically.

  Although not shown in detail, the first internal flow path 40 includes an introduction port and a discharge port connected to the gas supply line 1, and a hollow thin tube and a bypass portion that diverge between these ports and then merge. is there.

  The first flow rate sensor 41 includes, for example, a pair of thermal sensors (thermal sensors) provided in a hollow thin tube, and the instantaneous flow rate of the fluid is detected as an electrical signal by the thermal sensor, and the internal electrical circuit The electric signal is amplified and output as a flow rate measurement signal having a value corresponding to the detected flow rate.

  For example, the first valve 42 is configured such that its opening degree can be changed by an actuator using a piezoelectric element. The actuator is driven by an opening control signal from the first valve control unit 43, and the valve opening is adjusted to an opening corresponding to the value of the opening control signal.

The first valve control unit 43 includes a CPU (not shown), an internal memory, an A / D converter, a digital or analog electric circuit having a D / A converter, a communication interface for communicating with the first valve 42, and the like. It consists of an interface. And the 1st valve control part 43 is constituted so that the following functions may be realized by operating a CPU and its peripheral devices cooperatively according to the program memorized by the above-mentioned internal memory. For example, the first valve control unit 43 receives a command signal from the outside such as the information processing apparatus 7 interprets the contents, for example, if the command signal indicates a set flow rate Q _R is first measured flow rate Q _C is the local feedback controlled so that the set flow rate Q _R. Specifically, the first measured flow rate Q _C is measured by the first flow rate sensor 41 of the thermal type is, such that the set flow rate Q _R, the feedback value subjected to feedback calculation on the deviation of the first valve 42 An opening control signal for controlling the valve opening is generated, and the opening control signal is output to the first valve 42. In addition, when the command signal input from the outside is a fully closed signal or a fully opened signal, the opening degree that maintains the fully closed opening degree or the fully opened opening degree by the open loop control without performing the first feedback control unit local feedback control. A control signal is generated, and the opening degree control signal is output to the first valve 42.

  Here, the reference flow rate control device 5 is a differential pressure type mass flow rate control device (differential pressure type mass flow controller), and as shown in FIG. 2, a second internal flow path 50 through which gas flows, and this second internal flow rate A second valve 51 provided on the flow path of the path 50, a resistor 52 for differential pressure generation, an inlet side pressure sensor 53 and an outlet side pressure sensor 54 for measuring the pressure at each end of the resistor 52, A temperature sensor 55 that detects the temperature of the gas flowing in the second internal flow path 50 on the inlet side and a second valve control unit 56 are provided.

  The second internal flow path 50 is opened with the upstream end as an introduction port and the downstream end as a lead-out port. The introduction port has a pneumatic valve, a pressure regulator, and a gas cylinder (all not shown) via an external pipe. Is connected.

  Although not shown in detail, the second valve 51 is configured such that the valve opening degree can be changed by an actuator made of a piezo element or the like, and an opening degree control signal is sent from the second valve control unit 56. When given, the actuator is driven to adjust the valve opening according to the value of the opening control signal to control the gas flow rate.

  The resistor 52 includes an introduction port for introducing the gas flowing from the flow rate control valve 51 and a discharge port for deriving it, and generates a differential pressure between these introduction ports. In this embodiment, as the resistor 52, for example, a nonlinear resistor such as a laminar flow element having a characteristic that the differential pressure differential value of the flow rate flowing through the resistor 52 decreases as the differential pressure decreases.

  There are two pressure sensors, an inlet side pressure sensor 53 and an outlet side pressure sensor 54. The inlet side pressure sensor 53 detects the pressure of the gas flowing through the second internal flow path 50 on the primary side of the resistor 52, that is, the inlet side. The outlet side pressure sensor 54 detects the pressure of the gas flowing through the internal channel 50 on the secondary side of the resistor 52, that is, the outlet side. In this embodiment, absolute pressure type pressure sensors are used for the pressure sensors 53 and 54.

  From the resistor 52, the pressure sensors 53 and 54, and a flow rate calculation unit (not shown) that calculates the flow rate of the fluid flowing through the second internal flow path 50 based on the pressure measured by the pressure sensors 53 and 54. A second flow rate sensor 5S serving as a reference is configured.

The second valve control unit 56 includes a CPU (not shown), an internal memory, an A / D converter, a digital or analog electric circuit having a D / A converter, a communication interface for communicating with the second valve 51, and the like. It consists of an interface. And the 2nd valve control part 56 is constituted so that the following functions may be realized by operating CPU and its peripheral devices in cooperation according to the program memorized by the internal memory. For example, the second valve control unit 56 receives a command signal from the outside such as the information processing apparatus 7 interprets the contents, for example, if the command signal indicates a set flow rate Q _R, the second measured flow rate Q _S is the local feedback controlled so that the set flow rate Q _R. More specifically, the second valve control unit 56 calculates the deviation between the second measured flow rate Q _S measured by the second flow sensor 5S differential pressure between the set flow rate Q _R, at least proportional calculation on the deviation (Integration calculation, differentiation calculation, etc. may be included in addition) and the second valve 51 is feedback-controlled. That is, the second valve control unit 56 is configured to generate an opening control signal indicating a feedback value obtained by performing feedback calculation on the deviation, and to output the opening control signal to the flow control valve 51. Yes. In addition, when the command signal input from the outside is a fully closed signal or a fully opened signal, the second valve control unit 56 performs the fully closed opening or the fully opened opening by the open loop control without performing the local feedback control. Is generated, and the opening degree control signal is output to the second valve 51.

  The pressure control device 6 is composed of, for example, a regulator, and performs feedback control so that the pressure in the downstream line of the pressure control device 6 becomes the target pressure. The value of the target pressure can be set by a command signal from the information processing device 7.

  The information processing device 7 includes a CPU or internal memory (not shown), a digital or analog electric circuit having an A / D converter, a D / A converter, etc., a flow rate control device 4 to be inspected, and a flow rate control device 5 to be a reference. It is composed of a communication interface, an input interface, a display device such as a liquid crystal display, etc. for communication with each part of the above, may be dedicated, or uses a general-purpose computer such as a personal computer for part or all It may be as described above. Further, it may be configured not to use a CPU but to function as the following units only with an analog circuit, or a part of the functions may be a control device (not shown) or each flow rate control device in the semiconductor manufacturing apparatus P. It does not need to be physically integrated, such as sharing the flow rate control processing means 4 and 5, and may be composed of a plurality of devices connected to each other by wire or wirelessly.

  The information processing device 7 stores the program for the inspection system of the flow rate control device in the internal memory, and the CPU and its peripheral devices operate in cooperation with each other according to the program. As shown, at least the functions of the command output unit 71, the flow rate control switching unit 72, the inspection unit 73, and the like are exhibited. Hereinafter, each part will be described in detail.

  The command output unit 71 outputs a command signal for inspection with an inspection start command by a predetermined operation of the input interface as a trigger, and a flow control device 4 to be inspected, a flow control device 5 to be a reference, a pressure control device 6, the operation based on the command signal is performed. A specific inspection operation will be described later.

Flow control switching section 72, together with accepting the second measured flow rate Q _S from the second flow rate sensor 5S flow measurement device 5 as a reference, and the flow control device 5 and the flow rate control device 4 to be the inspection target becomes the reference The pressure Pr is received from the pressure sensor P provided in the flow path 3 (dead volume). Then, the flow control switch 72, the second measured flow rate Q _S is a predetermined flow rate, or, if the pressure Pr to be measured by the pressure sensor P becomes a predetermined pressure, from the command output unit 71 The command signal to be output is switched, and the operation and flow rate control state of the flow rate control device 4 to be inspected and the flow rate control device 5 to be the reference are switched.

Checking unit 73 is for inspecting for on the basis of the second measured flow rate Q _S measured by the flow measuring device 5 which is a reference to the first measured flow rate Q _C is measured by flow measuring device 4 to be tested . In the present embodiment, compared first and measured flow rate Q _C is measured by flow measuring device 4 to be inspected, and a second measured flow rate Q _S measured by the flow measuring device 5 as a reference, the first measured flow rate Q _C is performed for determining test whether within a predetermined range of the second measured flow rate Q _S criteria, and outputs the test result. The output form of the test result can be appropriately set according to the embodiment such as screen output or print output.

  Next, a procedure for inspecting the inspection system A of the flow rate control apparatus configured as described above will be described with reference to the flowchart of FIG. 4 and FIGS.

  First, an inspection is started by a user operating the input interface of the information processing apparatus 7. Then, the inspection start command is transmitted to the command output unit 71 of the information processing device 7.

Command output unit 71 as a trigger the inspection start command, outputs a command signal, and outputs a full open command signal F _O on the flow controller 4 to be inspected, the flow uncontrolled first valve 43 is fully opened (Step ST1). In other words, the flow rate control device 4 to be inspected in this non-flow rate control state functions only as a mass flow meter.

  On the other hand, the command output unit 71 also outputs a command signal to the pressure control device 6, and the pressure in the flow path 3 (dead volume) on the downstream side of the pressure control device 6 is included in the command signal. The pressure control device 6 is caused to perform local feedback control so that the target pressure becomes (step ST2).

Then, the command output unit 71 to the flow control device 5 as a reference, and outputs a command signal including a set flow rate Q _R, made to perform a local feedback control to the flow control device 5 as a reference, the reference become flow control device 5 the flow control state (state in which the second valve control unit 56 based on the deviation between the second measured flow rate Q _S actually measured and the set flow rate Q _R shown by the command signal to the PID control, etc.) (Step ST3).

Flow control by the flow controller 5 serving as the reference, the second measured flow rate Q _S is acknowledged flow control switching unit 72 becomes a predetermined flow rate, or pressure Pr to be measured by the pressure sensor P becomes a predetermined pressure Will continue until. Here, the flow rate is a predetermined flow rate within a range predetermined based on the set flow rate Q _R, a pressure in a predetermined range relative to the target pressure with a predetermined pressure. That is, the fluid flow rate or pressure of the flow path 3 is stable in the vicinity of the set flow rate Q _R or target pressure, until the inspection start condition is ready flow rate control is continued by the flow control device 5 serving as the reference. That is, the control in the state shown in FIG. 2 is continued.

On the other hand, if the second measured flow rate is received to the flow control switch unit 72 Q _S or pressure Pr has reached a predetermined flow rate or predetermined pressure, the flow rate control switching unit 72 is output from the command output unit 71 The command signal is switched to switch the flow rate control state of each flow rate control device 4, 5 (step ST4).

That is, the flow rate control switching unit 72 switches the command signal output by the command output unit 71. More specifically, the step ST4 in the command output unit 71 since, outputs a command signal including a set flow rate Q _R relative to the flow control device 4 to be inspected, the flow control device 4 to be tested made to perform a local feedback control, the based flow control device 4 to be the inspection target deviation between the first measured flow rate Q _C actually measured and the set flow rate Q _R shown by the flow control state (command signal 1 valve control unit 43 is in a state where PID control or the like is performed) (step ST5).

Meanwhile, the command output unit 71 with respect to the flow control device 5 as a reference in step ST4 and subsequent outputs a command signal including a full open command signal F _O, and the flow rate uncontrolled state in which the second valve 51 is fully opened (Step ST6). That is, the flow rate control device 5 serving as a reference in this non-flow rate control state functions only as a mass flow meter. Note that the control states in step ST5 and step ST6 are as shown in FIG.

Then the inspection unit 73 compares the first actually measured flow rate Q _C received a second measured flow rate Q _S. The first measured flow rate Q _C indicated by the flow measurement signal for inspection is performed for determining test whether within a predetermined range of the second measured flow rate Q _S indicated by the reference of the flow measurement signal as a result thereof assay Is output (step ST7).

In this embodiment, the flow rate of the fluid is controlled at a plurality of points having different values by the flow rate control device 4 to be inspected and the flow rate control device 5 to be a reference, and the flow rate control to be inspected at each point. the first measured flow rate Q _C of the device 4, whether or not within a predetermined range of the second measured flow rate Q _S in the flow controller 5 serving as the reference, the measurement part 73 is configured to determine, respectively ( (Repeat step ST9 and steps ST1-8). Thus, by comparing the actually measured flow rates at several points, an accurate flow rate test result can be obtained in a wider flow range.

  Therefore, according to the inspection system A of the flow control device configured as described above, first, before the inspection by the inspection unit 73 is started, the flow control device 4 to be inspected is set to the flow non-control state, and the reference By controlling the fluid flow rate to a predetermined flow rate by the flow rate control device 5, the pressure of the fluid in the flow path 3 between the flow rate control device 4 to be inspected and the reference flow rate control device 5 is reduced in a short time. To charge up to the target pressure. That is, the waiting time until the test is started can be shortened as in the conventional case.

After the conditions for starting the verification are established, the flow control device 4 to be inspected is set to a flow control state, and the reference flow control device 5 is set to function as a mass flow meter in a flow non-control state. may flow rate is controlled by the first valve 42 in the vicinity of the first flow rate sensor 41 in which the first measured flow rate Q _C is that the flow rate is measured. Accordingly, since the respective distances are not separated, set flow rate Q _R is easy even flow control stable as was the low flow rate region, etc. wobble in the first measured flow rate Q _C is less likely to occur. Therefore, even determine whether the first measured flow rate Q _C of the inspection unit 73 performs in the flow control unit 4 to be inspected is in a flow rate control state is within a predetermined range with respect to the second measured flow rate Q _S It is easy to stabilize and the accuracy of inspection and verification can be improved especially in a low flow rate region. In addition, when the inspection unit 73 makes the determination, the second valve 51 of the reference flow rate control device 5 is fully open, so even if excessive pressure is in the flow path 3, it can be quickly eliminated. This also contributes to improving the stability and accuracy of inspection. Further, since the pressure between the flow control device 4 to be inspected and the flow control device 5 to be a reference is controlled to be constant by the pressure control device 6, the operation of the flow control device 4 to be inspected is stabilized. Inspection can be performed smoothly.

Further, the flow rate of the fluid is controlled at a plurality of points by the flow rate control device 4 to be inspected and the flow rate control device 5 to be a reference, and at each point, the first actually measured flow rate Q of the flow rate control device 4 to be inspected. _C has to whether it is within a predetermined range of the second measured flow rate Q _S in the flow controller 5 serving as the reference to determine respectively. Therefore, since the linearity and zero point of the flow rate can be known, more accurate determination can be performed.

  Furthermore, since a thermal type is used for the flow rate control device 4 to be inspected and a differential pressure type is used for the standard flow rate control device 5, it is possible to construct a high-performance gas system at a low price.

  In addition, since the flow control device 5 serving as a reference has a flow control valve 51 disposed upstream of the pressure sensors 53 and 54, and the sensors 53 and 54 are on the chamber side (vacuum side), The pressure change range can be limited, and a more accurate inspection can be performed.

  In addition, a plurality of inspection lines 3 are provided, and each inspection line 3 is provided with a reference flow rate control device 5 having a different flow rate range that can be inspected, in other words, a different flow rate control range. Inspection in the desired flow range can be performed with high accuracy.

  Another embodiment of the present invention will be described with reference to FIGS. In addition, the same code | symbol shall be attached | subjected to the member corresponding to the said embodiment.

  In this embodiment, only the first valve 42 of the flow rate control device 4 to be inspected is present on the flow path, and the second flow rate sensor 5S serving as a reference is used instead of the reference flow rate control device 5. Are provided on the downstream side of the flow rate control device 4 to be inspected.

  Until the conditions under which the inspection can be started are satisfied, the flow rate feedback in the first valve control unit 43 is based on the deviation between the set flow rate and the second actual flow rate measured by the second flow rate sensor 5S as shown in FIG. After the control is performed and the inspection is started, the flow rate feedback in the first valve control unit 43 is based on the deviation between the set flow rate and the first actual flow rate measured by the first flow rate sensor 41 as shown in FIG. Control is performed. That is, the flow rate of the fluid flowing through the flow path is controlled only by the first valve 42 from the start to the end of the inspection, but the measured flow rate to be sampled is switched.

  In other words, the inspection system A of the flow control device of this embodiment includes the first valve 42, the first flow sensor 41 that measures the flow rate of the fluid, and the first valve control that controls the opening degree of the first valve 42. The second flow rate sensor 5S serving as a reference and the flow rate of the fluid flowing through the flow path become a predetermined flow rate, for inspecting the flow rate control device 4 that is an inspection target including the unit 43, or A command for controlling the flow rate of the fluid flowing through the flow path based on the deviation between the set flow rate and the second measured flow rate measured by the second flow rate sensor until the pressure of the fluid flowing through the flow path reaches a predetermined pressure. After the command output unit 71 to output and the flow rate of the fluid flowing through the flow path become a predetermined flow rate, or the pressure of the fluid flowing through the flow path becomes a predetermined pressure, the command output unit performs the inspection. Target flow control device A setting command signal indicating a set flow rate is output, and the opening degree of the first valve 42 is determined based on a deviation between the set flow rate and the first actual flow rate measured by the first flow rate sensor 41 to the first valve control unit 43. The flow rate control switching unit 72 that switches the command output from the command output unit 71 so as to control the flow rate of the fluid flowing through the flow path, and the flow rate control device 4 to be inspected control the flow rate. And an inspection unit 73 that inspects the first actual flow rate measured by the flow rate control device 4 to be inspected based on the second actual flow rate measured by the second flow rate sensor serving as the reference. It is characterized by.

  In this way, the first valve 42 in the vicinity of the first flow rate sensor 41 while reducing the waiting time until the start of the inspection and reproducing the actual flow rate control state at the time of the inspection as in the above embodiment. By controlling the flow rate at, the stability in the low flow rate region can be improved and the inspection accuracy such as verification and calibration can be increased.

  As shown in this embodiment, the method of performing the inspection while controlling the flow rate only by the first valve 42 of the flow rate control device 4 to be inspected is the flow rate to be inspected as in the above embodiment. The present invention may be applied to the case where a reference flow rate control device 5 is provided downstream of the control device 4. That is, even when there is a reference flow control device 5, inspection such as verification or calibration may be performed without using the second valve 51.

  Other embodiments will be described.

  In the embodiment, the flow rate control device to be inspected is a thermal flow rate control device, and the reference flow rate control device is a pressure type flow rate control device. However, the measurement principle is not particularly limited. For example, both the flow rate control device to be inspected and the reference flow rate control device may be a differential pressure type flow rate control device or a thermal type flow rate control device. Alternatively, the flow rate control device to be inspected may be a pressure type flow rate control device, and the reference flow rate control device may be a thermal type flow rate control device.

  In the embodiment, the inspection unit determines whether the first actual flow rate measured by the flow control device to be inspected is within a predetermined range with respect to the second actual flow rate measured by the reference flow control device. However, the inspection unit may be configured to calibrate the flow rate control device to be inspected. More specifically, the inspection unit calibrates the first actual flow rate measured by the flow control device to be inspected based on the second actual flow rate measured by the reference flow control device. It may be configured. For example, without comparing the first measured flow rate and the second measured flow rate, the setting parameters of the calibration curve and the flow rate calculation formula stored in the flow control device to be inspected are changed so as to be the second measured flow rate. You may do it. In short, in addition to determining whether or not the first actually measured flow rate shows a correct value in the inspection unit, it may be performed up to some setting change so that the first actually measured flow rate shows a correct value.

  In the above embodiment, the pressure control device is configured to make the pressure of the fluid constant. However, the pressure control device is omitted, and the pressure is charged as a result of the flow control of the reference flow control device. It does not matter if it is kept at. Note that the pressure control device may be provided between the flow control device to be inspected and the reference flow control device. In addition, the switching between the flow control state and the flow non-control state of each flow control device may be made on the condition that both the pressure has become a predetermined pressure and the flow rate has become a predetermined flow rate, or only one of them. May be used as the switching condition. In the embodiment, the flow rate control switching unit is configured to monitor the second actually measured flow rate of the reference flow rate control device and switch the flow rate control state and the non-flow rate control state to the command output unit according to the value. However, for example, the switching may be performed based on the first actually measured flow rate of the flow rate control device to be inspected.

  Furthermore, the flow control switching unit switches the flow control state or the flow non-control state of the nuclear flow control device when entering a stable state where the fluid pressure becomes constant or the fluid flow rate becomes constant. Alternatively, the flow rate control state or the flow rate non-control state may be switched after a predetermined time has elapsed since becoming a stable state. In other words, the flow control switching unit may be configured to switch the flow control state or the non-flow control state of each flow control device after the stable state continues.

  Further, in the flow non-control state, the opening of the valve is not limited to full opening, but may be maintained at a predetermined constant opening. In short, as long as the charging of the pressure does not take time or does not interfere with the inspection in the inspection unit, the flow rate non-controlled state may be realized by keeping the opening constant in the vicinity of the fully open state. In addition, the set flow rate may be different before and after switching of the flow rate control.

  In order to add the configuration of the present invention to the inspection system of the existing flow control device and enjoy the effect, at least the function as the command output unit, flow control switching unit, and inspection unit of the above embodiment What is necessary is just to utilize the program for test | inspection systems for implement | achieving, or the program recording medium on which the said program was recorded.

  In addition, various modifications and combinations of embodiments may be performed without departing from the spirit of the present invention.

A ... Inspection system 3 of flow control device ... Flow path 4 ... Flow control device 41 to be inspected ... First flow sensor 42 ... First valve 43 ... First valve control Unit 5 ... Reference flow rate control device 51 ... Second valve 5S ... Second flow rate sensor 56 ... Second valve control unit 71 ... Command output unit 72 ... Flow rate control switching unit 73 ... Inspection section

Claims (12)

A first flow rate sensor that measures the flow rate of the fluid, and a flow rate control device that is a test target that includes a first valve control unit that controls the opening degree of the first valve, and a second flow rate that serves as a reference The flow rate control device to be inspected from the upstream side and the flow rate control device to be inspected provided in series in the order of the second flow rate sensor to be the reference on the flow path through which the fluid flows. A method,
Until the flow rate of the fluid flowing through the flow path becomes a predetermined flow rate or until the pressure of the fluid flowing through the flow path becomes a predetermined pressure, the set flow rate and the second actually measured flow rate measured by the second flow rate sensor An initial flow rate control step for controlling the flow rate of the fluid flowing through the flow path based on the deviation;
After the flow rate of the fluid flowing through the flow path becomes a predetermined flow rate, or after the pressure of the fluid flowing through the flow path becomes a predetermined pressure, the set flow rate and the first flow rate sensor are connected to the first valve control unit. A flow rate control switching step of controlling the flow rate of the fluid flowing through the flow path by controlling the opening of the first valve based on the deviation of the first actually measured flow rate to be measured;
In a state where the flow rate of the fluid flowing through the flow path is controlled based on the deviation between the set flow rate and the first measured flow rate, the first measured flow rate measured by the flow control device to be inspected is used as the reference. An inspection method for a flow rate control device, comprising: an inspection step for inspecting based on a second actual flow rate measured by a second flow rate sensor. A reference flow control device including a second valve, the reference second flow rate sensor, and a second valve control unit that controls the opening of the second valve is downstream of the flow control device to be inspected. It is provided in
In the initial flow rate control step, the first valve control unit of the flow rate control device to be inspected is kept at a constant opening degree of the first valve, and the flow rate control device to be inspected is not flow-controlled. The second flow rate control device is provided with a set flow rate, and the second valve control unit is provided with a set flow rate and a second measured flow rate measured by the second flow rate sensor is determined based on the second measured flow rate. By controlling the opening of the valve, the reference flow control device is in a flow control state,
In the flow rate control switching step, a set flow rate is given to the flow rate control device to be inspected, and the first valve control unit is based on a deviation between the set flow rate and the first actually measured flow rate measured by the first flow rate sensor. The flow control device to be inspected is set to a flow control state by controlling the opening degree of the first valve, and the second valve control unit of the reference flow control device has an opening of the second valve. 2. The flow rate control device inspection method according to claim 1, wherein the reference flow rate control device is kept in a non-flow rate control state while maintaining a constant degree.   The flow rate control device inspection method according to claim 2, wherein, in the initial flow rate control step, the first valve control unit of the flow rate control device to be inspected is fully opened.   The flow rate control device inspection method according to claim 2 or 3, wherein, in the flow rate control switching step, the second valve control unit of the reference flow rate control device is made to fully open the opening of the second valve.   A plurality of different values are set as the set flow rate, and in the inspection step, a first measured flow rate measured by the flow rate control device to be inspected at each set flow rate is measured by the reference flow rate control device. 5. The inspection method for a flow control device according to claim 2, wherein each inspection is performed based on the actually measured flow rate.   A pressure control device for controlling the pressure of the fluid flowing in the flow path to be constant is upstream of the flow control device to be inspected, or the flow control device to be inspected and the reference flow control device An inspection method for a flow control device according to any one of claims 2 to 5, further provided between the two.   The first flow rate sensor of the flow control device to be inspected measures the flow rate based on the temperature of the fluid, and the second flow rate sensor of the reference flow rate control device measures the flow rate based on the pressure of the fluid. An inspection method for a flow rate control device according to any one of claims 2 to 6.   In the inspection step, whether or not the first actual flow rate measured by the flow control device to be inspected is within a predetermined range with respect to the second actual flow rate measured by the reference flow control device. The inspection method for a flow control device according to any one of claims 2 to 7, further comprising a verification step of performing verification.   The inspection step includes a calibration step of calibrating a first actually measured flow rate measured by the flow rate control device to be inspected based on a second actually measured flow rate measured by the reference flow rate control device. The inspection method of the flow control device according to any one of 8. In the initial flow rate control step, the first valve control unit of the flow rate control device to be inspected is based on a deviation between a set flow rate and a second actually measured flow rate measured by the second flow rate sensor serving as the reference. Control the opening of one valve,
In the flow rate control switching step, the first valve control unit of the flow rate control device to be inspected is based on a deviation between a set flow rate and a first actually measured flow rate measured by the first flow rate sensor. The flow rate control device inspection method according to claim 1, wherein the opening degree is controlled. A flow rate control device used for inspection of a flow rate control device to be inspected comprising a first valve, a first flow rate sensor for measuring the flow rate of fluid, and a first valve control unit for controlling the opening degree of the first valve. Inspection system,
A second flow rate sensor serving as a reference provided on the downstream side of the flow rate control device to be inspected on the flow path through which the flow rate flows;
Until the flow rate of the fluid flowing through the flow path becomes a predetermined flow rate or until the pressure of the fluid flowing through the flow path becomes a predetermined pressure, the set flow rate and the second actually measured flow rate measured by the second flow rate sensor A command output unit that outputs a command for controlling the flow rate of the fluid flowing through the flow path based on the deviation;
After the flow rate of the fluid flowing through the flow path becomes a predetermined flow rate or the pressure of the fluid flowing through the flow path becomes a predetermined pressure, the command output unit is set in the flow rate control device to be inspected. A setting command signal indicating a flow rate is output, and the first valve control unit is configured to control the opening of the first valve based on a deviation between the set flow rate and the first actual flow rate measured by the first flow rate sensor. A flow rate control switching unit for switching a command output from the command output unit so as to control a flow rate of the fluid flowing through the flow path;
In a state where the flow control device to be inspected controls the flow rate, the first actually measured flow measured by the flow control device to be inspected is used as the second actual flow rate measured by the second flow sensor as the reference. An inspection system for a flow rate control device, comprising: A first valve, a first flow sensor for measuring the flow rate of a fluid, and a first flow rate control device that controls a first valve control unit for controlling the opening degree of the first valve are used for inspection of a flow rate control device to be inspected. A program used for an inspection system of a flow control device including a second flow sensor serving as a reference provided on a downstream side of the flow control device to be inspected on a flow path through which the flow rate flows,
Until the flow rate of the fluid flowing through the flow path becomes a predetermined flow rate or until the pressure of the fluid flowing through the flow path becomes a predetermined pressure, the set flow rate and the second actually measured flow rate measured by the second flow rate sensor A command output unit that outputs a command for controlling the flow rate of the fluid flowing through the flow path based on the deviation;
After the flow rate of the fluid flowing through the flow path becomes a predetermined flow rate or the pressure of the fluid flowing through the flow path becomes a predetermined pressure, the command output unit is set in the flow rate control device to be inspected. A setting command signal indicating a flow rate is output, and the first valve control unit is configured to control the opening of the first valve based on a deviation between the set flow rate and the first actual flow rate measured by the first flow rate sensor. A flow rate control switching unit for switching a command output from the command output unit so as to control a flow rate of the fluid flowing through the flow path;
In a state where the flow control device to be inspected controls the flow rate, the first actually measured flow measured by the flow control device to be inspected is used as the second actual flow rate measured by the second flow sensor as the reference. A program for an inspection system of a flow rate control device, which causes a computer to exhibit a function as an inspection unit for inspecting based on the above.