KR20170033236A - Method of calculating output flow rate of flow rate controller - Google Patents

Abstract

An output flow rate of a flow rate controller is obtained by using existing elements in a gas supply system. According to one embodiment, a gas, whose flow rate is adjusted by a flow rate controller as a measurement target, is supplied into a processing vessel in a state that a third valve of the gas supply system provided at an upstream side of the processing vessel is opened. While the gas is continuously supplied, the third valve is closed after a pressure measurement value of a pressure gauge within a flow rate controller for pressure measurement is stabilized. After the third valve is closed, an output flow rate of the flow rate controller as the measurement target is calculated from a previously known volume of the gas supply system in which the gas supplied through the flow rate controller as the measurement target is collected and a rise rate of the pressure measurement value of the pressure gauge within the flow rate controller for pressure measurement with respect to time.

Description

[0001] METHOD OF CALCULATING OUTPUT FLOW RATE OF FLOW RATE CONTROLLER [0002]

An embodiment of the present invention relates to a method for obtaining an output flow rate of a flow controller.

In the manufacture of an electronic device such as a semiconductor device, a substrate processing apparatus is used. Gas for processing the substrate into the processing container of the substrate processing apparatus is supplied from the gas supply system. The gas supply system is generally configured to supply one or more gases selected from plural kinds of gases to the processing vessel of the substrate processing apparatus. In addition, the gas supply system has a plurality of flow controllers dedicated to each of a plurality of types of gas so as to separately adjust the flow rates of the plurality of kinds of gases.

A pressure-controlled flow controller is known as a flow controller. This type of flow controller operates to reduce the error between the set flow rate, which is the target value, and the calculated flow rate, which is obtained from the measured pressure value of the pressure gauge of the flow controller concerned. However, the output flow rate of the flow controller becomes a flow rate having a large error with respect to the actual output flow rate of the flow controller with the passage of the use time. Therefore, it is necessary to obtain the output flow rate of the flow controller. As a method for obtaining the output flow rate of the flow controller, a method called a build-up method is known. The build-up method is described in Patent Document 1.

In the build-up method, the gas is supplied into the processing vessel of the substrate processing apparatus via the flow controller to be measured, and the gas is supplied from the pressure inside the processing vessel, the temperature inside the processing vessel, The output flow rate of the target flow controller is calculated.

Japanese Patent Specification No. 5,286,430

However, since the volume of the inside of the processing vessel is very large, the conventional build-up method described above includes an error factor. For example, the conventional build-up method is influenced by at least one of the temperature difference inside the processing vessel and the change over time of the processing vessel. A measure for obtaining the output flow rate of the flow rate controller by providing a flow rate measuring device in the gas supply system without using the processing vessel is taken into consideration. However, such a measure results in a cost increase of the gas supply system.

Therefore, it is desired to obtain the output flow rate of the flow controller using existing elements in the gas supply system.

In one aspect, a method for obtaining an output flow rate of a flow rate controller of a gas supply system for supplying a gas into a processing container of a substrate processing apparatus is provided. The gas supply system includes a plurality of first pipes, a plurality of first valves, a plurality of flow controllers, a plurality of second pipes, a plurality of second valves, a third pipe and a third valve. The plurality of first pipes are pipings connected to the plurality of gas sources, respectively. The plurality of first valves are provided in the plurality of first pipes. The plurality of flow controllers are pressure controlled flow controllers, and are provided downstream of the plurality of first pipes. A plurality of second piping are provided downstream of the plurality of flow controllers. The plurality of second valves are provided in the plurality of second pipes. And the third pipe is provided downstream of the plurality of second pipes. And the third valve is provided in the third pipe. (A) a first step of starting supply of the gas whose flow rate has been adjusted by the flow controller to be measured into the processing vessel among a plurality of flow controllers, with the third valve being open; (b) A second step of closing the third valve after the measured pressure value of the pressure gauge in the flow rate controller for pressure measurement is stabilized in a plurality of flow controllers in a state where supply of the gas into the processing vessel is continued; The known capacity of the gas supply system in which the gas supplied through the flow controller of the measurement object is stored after the third valve is closed in the process and the time of the measured pressure value of the pressure gauge in the flow controller for pressure measurement And a third step of calculating the output flow rate of the flow controller to be measured from the rate of increase.

According to one aspect of the present invention, a flow controller of one of a plurality of conventional flow controllers is used as a flow controller for pressure measurement in a gas supply system, and the flow rate controller And the output flow rate of the flow controller from the known volume in the gas supply system. Thus, according to this method, it is possible to obtain the output flow rate of the flow controller using the existing elements in the gas supply system.

In one embodiment, the flow controller to be measured and the flow controller for pressure measurement may be one of the flow controllers of the plurality of flow controllers. The one flow controller has an orifice, a control valve on the upstream side of the orifice, a first pressure gauge for measuring the pressure of the gas line between the control valve and the orifice, and a second pressure gauge downstream of the orifice. In the first step of this embodiment, only the first valve upstream of one of the plurality of first valves is opened and only the second valve downstream of one of the plurality of second valves opens State is formed. In the second step, after the measured pressure value measured by the second pressure gauge of the one flow controller is stabilized, the third valve is closed. In the third step, the rate of increase of the measured pressure value of the second pressure gauge with respect to time is used as the rate of increase of the measured pressure value of the pressure gauge in the flow rate controller for measuring time with respect to time.

In another embodiment, the flow controller to be measured is a first flow controller of the plurality of flow controllers, and the flow controller for pressure measurement may be a second flow control different from the first one of the plurality of flow controllers. Each of the first flow controller and the second flow controller has an orifice, a control valve on the upstream side of the orifice, and a pressure gauge for measuring the pressure of the gas line between the control valve and the orifice. In the first step of this embodiment, only the first valve upstream of the first one of the plurality of first valves is opened and the second one of the plurality of second valves downstream of the first flow controller, Only the second valve downstream of the flow controller is open. Further, the method of this embodiment is characterized in that (d) after the execution of the first step and before the execution of the second step, the measurement pressure value of the pressure gauge of the second flow rate controller is (E) a step of measuring a pressure value of a predetermined time from the execution of the second step, before the execution of the third step, and after the first measured pressure value is obtained And then closing the second valve downstream of the first flow controller. In the second step, the third valve is closed immediately after the first measured pressure value is obtained. In the third step, the difference between the second measured pressure value, which is the measured pressure value when the measured pressure value of the pressure gauge of the second flow controller is stable, and the first measured pressure value, The value divided by the predetermined time is used.

In another aspect, there is also provided a method of determining an output flow rate of a flow rate controller of a gas supply system for supplying a gas into a processing container of a substrate processing apparatus. The gas supply system includes a plurality of first pipes, a plurality of first valves, a plurality of flow controllers, a plurality of second pipes, a plurality of second valves, a third pipe and a third valve. The plurality of first pipes are pipings connected to the plurality of gas sources, respectively. The plurality of first valves are provided in the plurality of first pipes. The plurality of flow controllers are pressure controlled flow controllers, and are provided downstream of the plurality of first pipes. A plurality of second piping are provided downstream of the plurality of flow controllers. The plurality of second valves are provided in the plurality of second pipes. And the third pipe is provided downstream of the plurality of second pipes. And the third valve is provided in the third pipe. One of the plurality of flow controllers has an orifice, a control valve on the upstream side of the orifice, a first pressure gauge for measuring the pressure of the gas line between the control valve and the orifice, And has a second pressure gauge. (A) a first valve upstream of said one of said plurality of first valves, a second valve downstream of said one of said plurality of second valves, and A first step of starting supply of the gas whose flow rate has been adjusted by the one flow controller to the processing vessel in a state in which the three valves are opened, (b) in the state where supply of gas into the processing vessel is continued, A second step of closing the second valve downstream of the one flow controller after the measurement pressure value of the second pressure gage of one flow controller is stabilized; and (c) a second step of closing the second valve downstream of the one flow controller And a control means for controlling the flow rate of the gas to be supplied to the flow rate controller based on a known volume of the gas supply system in which the gas supplied through the one flow controller is stored, From the increase rate, and a third step of calculating an output flow rate of the one of the flow controllers. In this method, the known volume on the upstream side of the second valve downstream of one flow controller is used to obtain the output flow rate of the one flow controller.

As described above, it is possible to obtain the output flow rate of the flow controller by using the existing elements in the gas supply system.

1 is a flowchart showing an embodiment of a method for obtaining the output flow rate of a flow rate controller of a gas supply system for supplying a gas into a processing container of a substrate processing apparatus.
2 is a diagram illustrating a gas supply system.
Fig. 3 is a diagram showing the state of the valve in the gas supply system after the execution of the process (ST2). Fig.
4 is a flowchart showing another embodiment of a method for obtaining the output flow rate of the flow controller of the gas supply system for supplying gas into the processing container of the substrate processing apparatus.
5 is a diagram showing the state of a valve in the gas supply system after the execution of the process (ST23).
6 is a flowchart showing another embodiment of a method for obtaining the output flow rate of a flow controller of a gas supply system for supplying gas into a processing container of a substrate processing apparatus.
Fig. 7 is a diagram showing the state of the valves in the gas supply system after execution of the process (ST32). Fig.

Hereinafter, various embodiments will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals.

1 is a flowchart showing an embodiment of a method for obtaining the output flow rate of a flow rate controller of a gas supply system for supplying a gas into a processing container of a substrate processing apparatus. The method MT1 shown in Fig. 1 is applicable to the gas supply system shown in Fig. 2, for example.

The gas supply system GP shown in Fig. 2 includes a plurality of first pipelines L1, a plurality of first valves V1, a plurality of flow controllers FC, a plurality of second pipelines L2, A valve V2, a third pipe L3, and a third valve V3.

One end of the plurality of first pipes L1 is connected to a plurality of gas sources GS, respectively. The plurality of gas sources GS is a source of gas used for processing the substrate in the substrate processing apparatus SP. A plurality of first valves (V1) are respectively provided in the plurality of first pipes (L1).

A plurality of flow controllers FC are provided downstream of the plurality of first pipes L1 and downstream of the plurality of first valves V1. The plurality of flow controllers FC are connected to the other end of the downstream side of the plurality of first pipes L1. A plurality of second pipes L2 are provided downstream of the plurality of flow controllers FC. One end of the second pipe L2 is connected to each of the plurality of flow controllers FC. A plurality of second valves (V2) are respectively provided in the plurality of second pipes (L2).

A third pipe L3 is provided downstream of the plurality of second pipes L2 and downstream of the plurality of second valves V2. The other end of the plurality of second pipes L2 is connected to one end of the third pipe L3. The third valve (V3) is provided in the third pipe (L3). The other end of the third pipe L3, that is, the end of the third pipe L3 downstream of the third valve V3 is connected to the processing vessel PC of the substrate processing apparatus SP. An exhaust device EA is provided downstream of the processing container PC via a pressure control valve APC.

The gas supply system GP further includes a pipe LP1, a valve VP1, a pipe LP2, a valve VP2, a plurality of pipes LP4 and a plurality of valves VP4. One end of the pipe (LP1) is connected to the source of a purge gas such as N ₂ gas. The pipe LP1 is provided with a valve VP1. The other end of the pipe LP1 is connected to the pipe LP2 and the pipe LP3 downstream of the valve VP1. One end of the pipe LP2 is connected to the pipe LP1 on the downstream side of the valve VP1 and the other end of the pipe LP2 is connected to the third pipe L3. The pipe LP2 is provided with a valve VP2.

One end of the pipe LP3 is connected to the pipe LP1 on the downstream side of the valve VP1. One end of a plurality of pipes LP4 is connected to the pipe LP3. The other end of the plurality of pipes LP4 is connected to the plurality of first pipes L1 on the downstream side of the plurality of first valves V1. These pipes LP4 are provided with a plurality of valves VP4, respectively.

The plurality of flow controllers FC are pressure controlled flow controllers. Each of the plurality of flow controllers FC has a control valve CV, an orifice OF, and a pressure gauge P1. Each of the plurality of flow controllers FC provides the gas line GL1 on the upstream side of the orifice OF and the gas line GL2 on the downstream side of the orifice OF. The gas line GL1 is connected to the corresponding first pipe L1 and the gas line GL2 is connected to the corresponding second pipe L2.

The control valve CV is provided in the gas line GL1 on the upstream side of the orifice OF.

A pressure gauge P1 for measuring the pressure of the gas line GL1 is connected to the gas line GL1 between the control valve CV and the orifice OF.

In one embodiment, the plurality of flow controllers FC include a flow controller FC1 and a flow controller FC2. The flow controller FC1 further includes a pressure gauge P2. On the other hand, among the plurality of flow controllers FC, the flow controller FC2 has no pressure gauge P2. The pressure gauge P2 is connected to the gas line GL2 for measuring the pressure of the gas line GL2.

The flow controller FC2 controls the flow rate of the gas flowing through the flow controller FC2 under the condition that the pressure of the gas line GL1 is at least twice the pressure of the gas line GL2. Specifically, the flow controller FC2 controls the control valve CV so as to reduce the difference between the calculated flow rate and the set flow rate, which is obtained from the measured pressure value of the pressure gauge P1. The set flow rate is set, for example, from a control unit Cnt described later.

The flow controller FC1 controls the control valve CV similarly to the flow controller FC2 under the condition that the pressure of the gas line GL1 is twice or more the pressure of the gas line GL2. Under the condition that the pressure of the gas line GL1 is smaller than twice the pressure of the gas line GL2, the flow rate controller FC1 controls the flow rate of the gas line GL2 from the pressure difference between the measured pressure value of the pressure gauge P1 and the measured pressure value of the pressure gauge P2 The control valve CV is controlled so as to reduce the difference between the calculated output flow rate and the set flow rate.

Further, as shown in Fig. 2, the gas supply system GP may further include a control unit Cnt. The control unit Cnt is also a control unit of the substrate processing apparatus SP, and is constituted by, for example, a computer device or the like. The control unit Cnt controls each part of the substrate processing apparatus SP and each part of the gas supply system GP in accordance with the recipe stored in the storage device for substrate processing in the substrate processing apparatus SP. The control unit Cnt also controls the valves of the gas supply system GP in various embodiments of the method for obtaining the output flow rate of the flow controller. In addition, the control unit Cnt receives the measured pressure value of the pressure gauge P1 or the measured pressure value of the pressure gauge P2 in various embodiments of the method, and calculates the output flow rate of the flow rate controller.

Hereinafter, referring again to FIG. As shown in Fig. 1, the method MT1 is a method of obtaining the output flow rate of the flow controller FC1 by using the measured pressure value of the pressure gauge P2 of the flow controller FC1. That is, in the method MT1, one flow controller FC1 is a flow controller to be measured and also a flow controller for pressure measurement. This method MT1 is started in step ST1.

In the process (ST1), supply of the gas whose flow rate is adjusted by the flow controller FC1 is started to the processing container PC. In this step ST1, the first valve V1 located upstream of the flow controller FC1 and the second valve V2 located downstream of the flow controller FC1 are opened, and the other first valve V1, The second valve V2, the valve VP1, the valve VP2 and the plurality of valves VP4 are closed. Further, in the step (ST1), the third valve (V3) is opened. Thereby, the gas from the gas source GS upstream of the flow controller FC1 flows through the first pipe L1, the flow controller FC1, the second pipe L2 and the third pipe L3, (PC). In this step (ST1), the exhaust device (EA) is operated and the pressure regulating valve (APC) is opened. The control of the valve of the gas supply system GP, the flow rate controller FC1, the pressure regulating valve APC, and the like in the step ST1 may be performed by the control unit Cnt.

In the subsequent step ST2, the measurement pressure value of the pressure gauge P2 is monitored while the supply of the gas into the processing vessel PC started in the step ST1 is continued. After the measured pressure value of the pressure gauge P2 is stabilized, the third valve V3 is closed. Further, for example, when the difference between the minimum value and the maximum value of the measured pressure value of the pressure gauge P2 within a predetermined time is equal to or less than a predetermined value, it can be judged that the measured pressure value of the pressure gauge P2 is stable. In this step ST2, the measured pressure value is sent to the control unit Cnt so that the measurement of the measured pressure value can be performed by the control unit Cnt or the control of the third valve V3 is performed on the control unit Cnt .

In the step ST2, when the third valve V3 is closed, the state of each valve of the gas supply system GP becomes the state shown in Fig. 3, a figure painted in black represents a valve closed, and a figure painted white in a figure represents a valve that is open.

After the execution of the process (ST2), the gas supplied via the flow controller FC1 is stored in the flow path shown by the thick line in Fig. Specifically, the gas line GL2 of the flow controller FC1, the inside of the second pipe L2 downstream of the gas line GL2, the inside of the third pipe L3 upstream of the third valve V3 And the flow controller FC other than the flow controller FC1 and the second pipeline L2 downstream of the second valve V2. The volume of the flow path in the gas supply system GP in which the gas is stored after the execution of the process ST2 is a volume previously measured before execution of the method MT1 and is a known volume Vk.

In the following step (ST3), the pressure increase rate (dP / dt) is obtained from the measured pressure value of the pressure gauge (P2) at a plurality of time points after the execution of the step (ST2). For example, a slope of a straight line approximating a relationship between a plurality of measured pressure values and a point at which a plurality of measured pressure values are obtained is obtained as a pressure increase rate. In step ST3, the output flow rate Q of the flow controller FC1 is calculated by the following equation (1).

Q = (dP / dt) x Vk / T x C (1)

In the equation (1), T is the temperature and may be the measurement temperature of the flow path in which the gas is stored or a predetermined temperature. Further, C is an integer and has a value specified by 22.4 (liter) / R. Also, R is a gas constant.

In this step ST3, the measured pressure value of the pressure gauge P2 may be sent to the control unit Cnt so that the calculation of the pressure increasing rate and the calculation of the output flow rate Q may be performed by the control unit Cnt. If all of the flow controllers FC have the same structure as the flow controller FC1, the method MT1 may be executed in order for all the flow controllers FC.

Hereinafter, another embodiment of a method for obtaining the output flow rate of the flow rate controller of the gas supply system for supplying gas into the processing container of the substrate processing apparatus will be described. 4 is a flowchart showing another embodiment of a method for obtaining the output flow rate of the flow controller of the gas supply system for supplying gas into the processing container of the substrate processing apparatus. The method MT2 shown in Fig. 4 is a method applicable to the gas supply system GP shown in Fig. In this method MT2, one flow controller FC is a flow controller to be measured, and the other flow controller FC is a flow controller for pressure measurement. Each of the flow controller for the measurement object and the flow controller for the pressure measurement may have either the structure of the flow controller FC1 or the structure of the flow controller FC2. Hereinafter, the method MT2 will be described by exemplifying the case where the flow controller FC1 is the flow controller to be measured and the flow controller FC2 is the flow controller for pressure measurement.

As shown in Fig. 4, the method MT2 is started in step ST21. In the process (ST21), supply of the gas whose flow rate is adjusted by the flow controller FC1 to the processing container PC is started. In this step ST21, the first valve V1 upstream of the flow controller FC1, the second valve V2 downstream of the flow controller FC1, and the second valve V2 downstream of the flow controller FC2, And the other first valve V1, the other second valve V2, the valve VP1, the valve VP2 and the plurality of valves VP4 are closed. Further, in the step ST21, the third valve V3 is opened. Thereby, the gas from the gas source GS upstream of the flow controller FC1 flows through the first pipe L1, the flow controller FC1, the second pipe L2 and the third pipe L3 And is supplied into the container (PC). In this step ST21, the exhaust system EA is activated and the pressure regulating valve APC is opened. The control of the valve of the gas supply system GP, the flow rate controller FC1, the pressure regulating valve APC, and the like in the step ST21 may be executed by the control unit Cnt.

In the following step ST22, the measurement pressure value of the pressure gauge P1 of the flow controller FC2 is monitored while the supply of the gas into the processing vessel PC started in the step ST21 is continued. Then, the measured pressure value when the measured pressure value of the pressure gauge P1 of the flow controller FC2 is stabilized is obtained as the measured pressure value Pm1. In step ST22, the measured pressure value of the pressure gauge P1 of the flow controller FC2 is sent to the control unit Cnt, and the monitoring of the measured pressure value and the acquisition of the measured pressure value Pm1 are carried out to the control unit Cnt .

In the following step ST23, the third valve V3 is closed immediately after the measurement pressure value Pm1 of the step ST22 is obtained. The control of the third valve V3 in this step ST23 may be performed by the control unit Cnt.

When the third valve V3 is closed in the step ST23, the state of each valve of the gas supply system GP becomes the state shown in Fig. In Fig. 5, a figure painted in black represents a closed valve, and a figure painted white in a figure represents an open valve. In the state shown in Fig. 5, the control valve CV of the flow controller FC2 is open.

After the execution of the process (ST23), the gas supplied via the flow controller FC1 is stored in the flow path indicated by the bold line in Fig. Specifically, the gas line GL2 of the flow controller FC1, the inside of the second pipe L2 downstream of the gas line GL2, the inside of the third pipe L3 upstream of the third valve V3 Upstream of the flow controller FC2 and also in the first pipe L1 downstream of the corresponding first valve V1 and upstream of the flow controller FC2 and downstream of the corresponding valve VP4, The gas line GL1 and the gas line GL2 of the flow controller FC2 and the second pipeline L2 downstream of the flow controller FC2 and the flow controller FC1 and the flow controller FC2 The gas is stored in the downstream of the flow controller FC other than the first valve V2 and the second pipe L2 downstream of the second valve V2. The volume of the flow path in the gas supply system GP in which the gas is stored after the execution of the step ST23 is a volume previously measured before the execution of the method MT2 and is the known volume Vk2.

In the state shown in Fig. 5, the control valve CV of the flow controller FC2 is open, but the control valve CV of the flow controller FC2 may be closed. When the control valve CV of the flow controller FC2 is closed, the known volume Vk2 is higher than the volume of the flow passage indicated by the thick line in Fig. 5, upstream of the flow controller FC2, V1 and the volume of the inside of the pipe LP4 downstream of the corresponding valve VP4 in the upstream of the flow controller FC2.

In the following step ST24, the second valve V2 downstream of the flow controller FC1 is closed after the execution of the process ST23 and a predetermined time elapsed from the time when the measured pressure value Pm1 is acquired . The control of the second valve V2 in this step ST23 may be executed by the control unit Cnt.

In the following step (ST25), the measured pressure value of the pressure gauge P1 of the flow controller FC2 is monitored. Then, the measured pressure value when the measured pressure value of the pressure gauge P1 of the flow controller FC2 is stabilized is obtained as the measured pressure value Pm2. If the difference between the minimum value and the maximum value in the predetermined time of the measured pressure value of the pressure gauge P1 of the flow controller FC2 is equal to or less than the predetermined value, the measured pressure value of the pressure gauge P1 of the flow controller FC2 is stabilized . Thereafter, in step ST25, the pressure increase rate dP / dt is obtained. The pressure rising rate is obtained by calculation of (Pm2 - Pm1) /? T. DELTA t is a time difference between the time point at which the measured pressure value Pm1 is acquired and the point at which the second valve V2 is closed in the step ST24.

In step ST25, the output flow rate Q of the flow controller FC1 is calculated by the following equation (2).

Q = (dP / dt) x Vk2 / TxC (2)

In the equation (2), T is the temperature and may be the measurement temperature of the flow path in which the gas is stored or a predetermined temperature. Further, C is an integer and has a value specified by 22.4 (liter) / R. Also, R is a gas constant.

In step ST25, the measured pressure value of the pressure gauge P1 of the flow controller FC2 is sent to the control unit Cnt to monitor the measured pressure value, calculate the pressure increase rate, and calculate the output flow rate Q Cnt). Alternatively, the method MT2 may be executed sequentially for all the flow controllers FC.

Hereinafter, another embodiment of a method for obtaining the output flow rate of the flow controller of the gas supply system for supplying the gas into the processing container of the substrate processing apparatus will be described. 6 is a flowchart showing another embodiment of a method for obtaining the output flow rate of a flow controller of a gas supply system for supplying gas into a processing container of a substrate processing apparatus. The method MT3 shown in Fig. 6 is a method applicable to the gas supply system GP shown in Fig. This method MT3 is a modification of the method MT1.

The method MT3 is started in step ST31. The process (ST31) is the same process as the process (ST1). In the method MT3, the process (ST32) is subsequently executed. In step ST32, the measurement pressure value of the pressure gauge P2 of the flow controller FC1 is monitored while the supply of the gas into the processing vessel PC started in step ST31 is continued. After the measured pressure value of the pressure gauge P2 is stabilized, the second valve V2 downstream of the flow controller FC1 is closed. For example, if the difference between the minimum value and the maximum value of the measured pressure value of the pressure gauge P2 within a predetermined time is equal to or less than a predetermined value, it can be determined that the measured pressure value of the pressure gauge P2 is stable. In this step ST32, the measured pressure value is sent to the control unit Cnt so that the measured value of the measured pressure can be monitored by the control unit Cnt or the second valve V2 downstream of the flow controller FC1. May be executed by the control unit Cnt.

When the second valve V2 downstream of the flow controller FC1 is closed in the step ST32, the state of each valve of the gas supply system GP becomes the state shown in Fig. In Fig. 7, a figure painted in black represents a valve closed, and a figure painted white in a figure represents a valve that is open.

After the execution of the process (ST32), the gas supplied via the flow controller FC1 is stored in the flow path shown by the thick line in Fig. Specifically, the gas is stored in the gas line GL2 of the flow controller FC1 and the upstream portion of the second valve V2 in the interior of the second pipe L2 downstream of the gas line GL2. The volume of the flow path in the gas supply system GP in which the gas is stored after the execution of the step ST32 is a volume previously measured before the execution of the method MT3 and is the known volume Vk3.

In the following step (ST33), the pressure increase rate (dP / dt) is obtained from the measured pressure value of the pressure gauge (P2) at a plurality of time points after the execution of the step (ST32). For example, a slope of a straight line approximating a relationship between a plurality of measured pressure values and a point at which a plurality of measured pressure values are obtained is obtained as a pressure increase rate. In step ST33, the output flow rate Q of the flow controller FC1 is calculated by the following equation (3).

Q = (dP / dt) x Vk3 / TxC (3)

In the formula (3), T is the temperature and may be the measurement temperature of the flow path in which the gas is stored or a predetermined temperature. C is an integer.

In this step ST33, the measured pressure value of the pressure gauge P2 may be sent to the control unit Cnt so that the calculation of the pressure increasing rate and the calculation of the output flow rate Q may be performed by the control unit Cnt. When all the flow controllers FC have the same structure as the flow controller FC1, the method MT3 may be executed in order for all the flow controllers FC.

It is possible to obtain the output flow rate of the flow controller of the gas supply system by using the measured pressure value of the pressure gauge of the conventional pressure control type flow controller of the gas supply system in all the methods of the above embodiments. Also, the above-mentioned known volume is the volume of the existing passage in the gas supply system GP, and the volume is smaller than the volume inside the processing vessel PC. Further, the temperature difference of the flow path is smaller than the temperature difference in the processing vessel PC, and the temperature of the flow path is stable. Therefore, in all the methods of the above-described embodiments, it is possible to obtain the output flow rate of the flow controller with high accuracy.

GP: Gas supply system
GS: Gas source
L1: First piping
L2: second piping
L3: Third piping
V1: first valve
V2: second valve
V3: third valve
FC, FC1, FC2: Flow controller
CV: Control Valve
OF: Orifice
P1: Pressure gauge
P2: Pressure gauge
SP: substrate processing device
PC: Processing vessel
APC: Pressure regulating valve
EA: Exhaust system
Cnt:

Claims (4)

A method for determining an output flow rate of a flow rate controller of a gas supply system for supplying a gas into a processing vessel of a substrate processing apparatus,
The gas supply system includes:
A plurality of first pipes connected respectively to the plurality of gas sources,
A plurality of first valves provided in the plurality of first pipes,
A plurality of pressure control type flow controllers provided downstream of the plurality of first pipes,
A plurality of second pipes provided downstream of the plurality of flow controllers,
A plurality of second valves provided in the plurality of second pipes,
A third piping provided downstream of the plurality of second piping and connected to the processing vessel of the substrate processing apparatus,
And a third valve
And,
The method comprises:
A first step of starting supply of the gas whose flow rate has been adjusted by the flow controller to be measured into the processing vessel among the plurality of flow controllers in a state in which the third valve is open;
A second step of closing the third valve after the measured pressure value of the pressure gauge in the flow rate controller for pressure measurement in the plurality of flow controllers is stabilized while the supply of the gas into the processing vessel is continued,
And a controller for controlling the flow rate of the gas supplied through the flow rate controller of the measurement object to be measured after the third valve is closed in the second step and the measured pressure value of the pressure gauge in the flow rate controller for measuring the pressure A third step of calculating the output flow rate of the flow controller to be measured from the rate of increase with respect to time
≪ / RTI > The method according to claim 1,
Wherein the flow controller for the measurement object and the flow controller for the pressure measurement are one of the plurality of flow controllers,
Said one flow controller having an orifice, a control valve upstream of said orifice, a first pressure gauge measuring the pressure of the gas line between said control valve and said orifice, and a second pressure gauge downstream of said orifice,
In the first step, only a first valve upstream of the one of the plurality of first valves is opened, and only a second valve downstream of the one of the plurality of second valves, An open state is formed,
In the second step, after the measured pressure value measured by the second pressure gauge of the one flow controller is stabilized, the third valve is closed,
In the third step, the rate of increase of the measured pressure value of the second pressure gauge with respect to time is used as the rate of increase of the measured pressure value of the pressure gauge in the flow rate controller for measuring the pressure with time
Way. The method according to claim 1,
Wherein the flow rate controller of the measurement object is a first one of the plurality of flow controllers,
Wherein the flow rate controller for pressure measurement is a second flow rate controller different from the first flow rate controller among the plurality of flow rate controllers,
Wherein each of the first flow controller and the second flow controller has an orifice, a control valve on the upstream side of the orifice, and a pressure gauge for measuring the pressure of the gas line between the control valve and the orifice,
In the first step, only the first valve among the plurality of first valves upstream of the first flow controller opens, and the second valve among the plurality of second valves downstream of the first flow controller, Only the second valve downstream of the second flow controller is opened,
The method comprises:
After the execution of the first step and prior to the execution of the second step, in a state in which the supply of the gas into the processing container is continued, the measurement of the pressure measured by the pressure gauge of the second flow controller Obtaining a pressure value as a first measured pressure value,
Closing the second valve downstream of the first flow controller when a predetermined time elapses after execution of the second process, before execution of the third process, and after the first measured pressure value is acquired fair
Further comprising:
In the second step, immediately after the acquisition of the first measured pressure value, the third valve is closed,
The second measured pressure value being a measured pressure value when the measured pressure value of the pressure gauge of the second flow controller is stable and the second measured pressure value being a measured pressure value of the second flow controller, And a value obtained by dividing the difference from the value by the predetermined time is used
Way. A method for determining an output flow rate of a flow rate controller of a gas supply system for supplying a gas into a processing vessel of a substrate processing apparatus,
The gas supply system includes:
A plurality of first pipes connected respectively to the plurality of gas sources,
A plurality of first valves provided in the plurality of first pipes,
A plurality of pressure control type flow controllers provided downstream of the plurality of first pipes,
A plurality of second pipes provided downstream of the plurality of flow controllers,
A plurality of second valves provided in the plurality of second pipes,
A third pipe provided downstream of the plurality of second pipes and connected to the processing container of the substrate processing apparatus,
And a third valve
And,
Wherein one of the plurality of flow controllers has an orifice, a control valve on the upstream side of the orifice, a first pressure gauge for measuring the pressure of the gas line between the control valve and the orifice, 2 With a pressure gauge,
The method comprises:
A first valve located upstream of said one of said plurality of first valves, a second valve located downstream of said one of said plurality of second valves and said third valve, A first step of starting supply of the gas whose flow rate has been adjusted by one flow controller into the processing vessel;
Closing the second valve downstream of the one flow controller after the measured pressure value of the second pressure gauge of the one flow controller is stabilized while the supply of the gas into the processing container is continued, The process,
Wherein the second valve is closed downstream of the one flow controller in the second step and the known volume of the gas supply system in which the gas supplied through the one flow controller is stored and the one volume A third step of calculating the output flow rate of the one flow controller from the rate of increase of the measured pressure value of the second pressure gauge of the controller with respect to time;
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