Method of monitoring liquid raw material and gas supply device

Abstract

To provide a method for monitoring a liquid raw material and a gas supply device for monitoring a liquid amount of a liquid raw material stored in a raw material storage tank.SOLUTION: There is provided a method of monitoring a liquid in a gas supply device, including: a raw material storage tank that stores the liquid raw material; a liquid level detector that detects a liquid level of the liquid raw material stored in the raw material storage tank; a gas inlet provided in the raw material storage tank and connected to a carrier gas supplier that supplies a carrier gas carrying a raw material gas to the raw material storage tank; a gas outlet provided in the raw material storage tank and connected to a gas discharger that discharges the raw material gas, along with the carrier gas, from the raw material storage tank; and a raw material inlet provided in the raw material storage tank and connected to a liquid raw material supplier that supplies the liquid raw material to the raw material storage tank. The method includes steps for: calculating a remaining amount of the liquid raw material on the basis of a usage amount of the raw material and a replenishment amount of the raw material; estimating a detection result of a virtual sensor from the calculated remaining amount of the liquid raw material; and monitoring the liquid raw material on the basis of a detection result of the liquid level detector and the estimated detection result of the virtual sensor.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a liquid feedstock monitoring method and a gas supply apparatus. [Background technology]

[0002] Patent Document 1 discloses a raw material storage tank having a level measuring means for detecting the position of the liquid level of the liquid raw material in a stepped manner. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-7289 A Summary of the Invention [Problem to be solved by the invention]

[0004] In one aspect, the present disclosure provides a liquid source monitoring method and a gas supply apparatus for monitoring the amount of liquid source stored in a source storage tank. [Means for solving the problem]

[0005] In order to solve the above problem, according to one aspect, there is provided a liquid monitoring method for a gas supply device comprising: a raw material storage tank for storing a liquid raw material; a liquid level detection unit for detecting a liquid level of the liquid raw material stored in the raw material storage tank; a gas inlet provided in the raw material storage tank and connected to a carrier gas supply unit for supplying a carrier gas that transports a raw material gas to the raw material storage tank; a gas outlet provided in the raw material storage tank and connected to a gas outflow unit for causing the raw material gas to flow out from the raw material storage tank together with the carrier gas; and a raw material inlet provided in the raw material storage tank and connected to a liquid raw material supply unit for supplying the liquid raw material to the raw material storage tank, the method comprising the steps of: calculating a remaining amount of the liquid raw material based on an amount of the raw material used and an amount of the raw material replenished; estimating a detection result of a virtual sensor from the calculated remaining amount of the liquid raw material; and monitoring the liquid raw material based on the detection result of the liquid level detection unit and the estimated detection result of the virtual sensor. Effect of the Invention

[0006] According to one aspect, it is possible to provide a liquid source monitoring method for monitoring the amount of liquid source stored in a source storage tank and a gas supply device. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a schematic diagram showing a configuration example of a gas supply device. [Diagram 2] FIG. 4 is a schematic diagram illustrating an example of a level detection position of a raw material storage tank. [Diagram 3] FIG. 4 is a functional block diagram of a liquid level monitoring unit. [Figure 4] 4 is a graph showing an example of a change in the liquid level of a liquid raw material. [Diagram 5] 11 is a flowchart showing an example of a liquid source refilling operation. [Figure 6] 4 is an example of a display screen displayed on a display unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and duplicated descriptions may be omitted.

[0009] [Gas supply device] The configuration of the gas supply device 30 according to this embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic diagram showing an example of the configuration of the gas supply device 30.

[0010] The gas supply device 30 is a device that supplies a raw material gas generated by heating the liquid raw material 31 together with a carrier gas to the processing vessel 10 of the substrate processing apparatus. The substrate processing apparatus performs a desired process (e.g., a film formation process) on the substrate in the processing vessel 10 by using the gas supplied from the gas supply device 30. The substrate processing apparatus having the processing vessel 10 may be, for example, a film formation apparatus, which performs a film formation process on the substrate by causing a plurality of substrates arranged on a turntable in the processing vessel 10 to revolve by rotating the turntable, and passing the substrates through an area to which a first gas (e.g., a raw material gas supplied from the gas supply device 30) is supplied and an area to which a second gas (e.g., a reaction gas that reacts with the raw material gas to form a desired film on the surface of the substrate) is supplied in order. Note that the substrate processing apparatus having the processing vessel 10 is not limited to a semi-batch type film formation apparatus, and may be, for example, a batch type film formation apparatus that performs a process on a plurality of substrates in the processing vessel 10 at once, a single-wafer type film formation apparatus that processes the substrates one by one, or a multiple-wafer film formation apparatus having a plurality of mounting stages in the processing vessel 10.

[0011] The liquid source 31 may be a source containing at least one of various metals such as aluminum (Al), hafnium (Hf), zirconium (Zr), titanium (Ti), or a source containing silicon (Si). As the carrier gas, an inert gas such as nitrogen (N2) gas or a rare gas (Ar, He) may be used.

[0012] The gas supply device 30 has a raw material storage tank 32 that stores the liquid raw material 31. The raw material storage tank 32 is also called a tank, an ampoule, or a reservoir. The raw material storage tank 32 has a tank body 32a formed in a cylindrical shape with a bottom, and a ceiling lid 32b that airtightly covers the ceiling of the tank body 32a. The tank body 32a and the ceiling lid 32b are made of a metal material such as stainless steel. The capacity of the raw material storage tank 32 is set to about 1 to 10 liters, for example. The lower part of the raw material storage tank 32 is a liquid phase part where the liquid raw material 31 is stored. The upper part of the raw material storage tank 32 is a gas phase part where the raw material gas is stored. The size of the gas phase part increases and decreases depending on the vertical movement of the liquid level of the liquid raw material 31. That is, the size of the gas phase part increases as the liquid level of the liquid raw material 31 decreases, and the size of the gas phase part decreases as the liquid level of the liquid raw material 31 increases.

[0013] The gas supplying device 30 has heating parts (main heating part 33a, ceiling heating part 33b) that generate raw material gas by heating the liquid raw material 31 stored in the raw material storage tank 32. Specifically, the gas supplying device 30 has a main heating part 33a that generates raw material gas by heating the bottom and side parts of the raw material storage tank 32, and a ceiling heating part 33b that heats the ceiling part of the raw material storage tank 32. Specifically, the main heating part 33a is provided so as to surround and cover almost the entire outer peripheral surface of the bottom and side parts of the tank body 32a. The ceiling heating part 33b is provided so as to cover almost the entire upper surface of the ceiling lid 32b. The main heating part 33a may be provided in a part of the tank body 32a. The ceiling heating part 33b may be provided in a part of the ceiling lid 32b.

[0014] The gas supply device 30 has a level sensor 35. The level sensor 35 detects the liquid level of the liquid raw material 31 stored in the raw material storage tank 32. The level sensor 35 has a rod-shaped level measurement body that is attached, for example, so as to penetrate the top cover 32b and extend into the raw material storage tank 32, and has multiple detection sensors 35a to 35d in the longitudinal direction (height direction) of the level measurement body to detect the presence or absence of the liquid raw material 31. When the liquid level of the liquid raw material 31 reaches or exceeds the position of each of the detection sensors 35a to 35d, each of the detection sensors 35a to 35d is in the ON state. When the liquid level of the liquid raw material 31 is below the position of each of the detection sensors 35a to 35d, each of the detection sensors 35a to 35d is in the OFF state. As a result, the level sensor 35 is configured to be able to recognize the position of the liquid level of the liquid raw material 31 stored in the raw material storage tank 32 in a stepped manner based on the detection results of each of the detection sensors 35a to 35d. A detection signal from the level sensor 35 (each of the detection sensors 35a to 35d) is sent to the liquid level monitoring unit 39 and the control unit 60.

[0015] FIG. 2 is an example of a schematic diagram illustrating the level detection positions of raw material storage tank 32. Raw material storage tank 32 shown in FIG. 2 has, from bottom to top, level detection positions "LL", "L", "H", and "HH". Detection sensor 35a is provided at level detection position "LL". Detection sensor 35b is provided at level detection position "L". Detection sensor 35c is provided at level detection position "H". Detection sensor 35d is provided at level detection position "HH".

[0016] For example, when the detection sensors 35a to 35d are not detecting the liquid source (OFF state), this indicates that the liquid level of the liquid source 31 is located below the level detection position "LL".

[0017] In addition, when detection sensor 35a detects liquid raw material (ON state) and detection sensors 35b to 35d do not detect liquid raw material (OFF state), this indicates that the liquid level of liquid raw material 31 is located between level detection position "LL" and level detection position "L."

[0018] In addition, when the detection sensors 35a, 35b detect the liquid raw material (ON state) and the detection sensors 35c, 35d do not detect the liquid raw material (OFF state), this indicates that the liquid level of the liquid raw material 31 is located between the level detection position "L" and the level detection position "H".

[0019] In addition, when the detection sensors 35a to 35c detect the liquid raw material (ON state) and the detection sensor 35d does not detect the liquid raw material (OFF state), this indicates that the liquid level of the liquid raw material 31 is located between the level detection position "H" and the level detection position "HH."

[0020] Moreover, when the detection sensors 35a to 35d detect the liquid source (ON state), this indicates that the liquid level of the liquid source 31 is located above the level detection position "HH".

[0021] Returning to FIG. 1, the top cover 32b of the raw material storage tank 32 is provided with a gas inlet , a gas outlet 37, and a raw material inlet .

[0022] A carrier gas supply unit that supplies a carrier gas for transporting the raw material gas to the raw material storage tank 32 is connected to the gas inlet 36. The carrier gas supply unit has a carrier gas supply source (not shown), a carrier gas flow path 36a, and a flow rate controller 36b and an on-off valve 36c that are interposed in the carrier gas flow path 36a. One end of the carrier gas flow path 36a is connected to the carrier gas supply source (not shown), and the other end is connected to the gas inlet 36.

[0023] A gas outlet section that causes the raw material gas to flow out from the raw material storage tank 32 together with the carrier gas is connected to the gas outlet 37. The gas outlet section has a gas flow path 37a, an on-off valve 37b interposed in the gas flow path 37a, and a flow path heater 37c provided in the gas flow path 37a. One end of the gas flow path 37a is connected to the gas outlet 37, and the other end is connected to the processing vessel 10. The control section 60 can supply the flow-controlled carrier gas to the raw material storage tank 32 by opening the on-off valves 36c and 37b and controlling the flow rate controller 36b. By supplying the flow-controlled carrier gas into the raw material storage tank 32 through the gas inlet 36, the saturated raw material gas flows out from the gas outlet 37 to the gas flow path 37a together with the carrier gas. Then, the raw material gas transported together with the carrier gas is supplied into the processing vessel 10. Moreover, the control unit 60 can close at least one of the on-off valves 36c, 37b to stop the supply of the source gas to the processing chamber 10. A flow path heater 37c, such as a tape heater, is provided along the gas flow path 37a to heat the gas flow path 37a to, for example, about 85 to 165° C. to prevent the source gas from liquefying.

[0024] A liquid raw material supply unit that supplies a liquid raw material to the raw material storage tank 32 is connected to the raw material inlet 38. The liquid raw material supply unit has a liquid raw material supply source (not shown), a liquid raw material flow path 38a, and a flow rate controller 38b and an on-off valve 38c that are interposed in the liquid raw material flow path 38a. One end of the liquid raw material flow path 38a is connected to the liquid raw material supply source (not shown), and the other end is connected to the raw material inlet 38. The control unit 60 can supply the liquid raw material whose flow rate is controlled to the raw material storage tank 32 by opening the on-off valve 38c and controlling the flow rate controller 38b. The control unit 60 can also stop the supply of the liquid raw material to the raw material storage tank 32 by closing the on-off valve 38c.

[0025] The gas supply device 30 includes a liquid volume monitoring unit 39 and a control unit 60.

[0026] The liquid amount monitoring unit 39 monitors the amount of the liquid raw material 31 stored in the raw material storage tank 32. The liquid amount monitoring unit 39 will be described later with reference to FIG.

[0027] The control unit 60 receives the detection results of the level sensor 35 (detection sensors 35a to 35d) and the result of the liquid volume monitoring unit 39. The control unit 60 also controls the flow rate of the carrier gas supplied from the carrier gas supply unit to the raw material storage tank 32 and the flow rate of the mixed gas of the carrier gas and the raw material gas supplied from the raw material storage tank 32 to the processing vessel 10 by controlling the flow rate controller 36b, the on-off valve 36c, 37b, etc. The control unit 60 also controls the replenishment amount of the liquid raw material supplied to the raw material storage tank 32 by controlling the flow rate controller 38b, the on-off valve 38c, etc.

[0028] The control unit 60 may be, for example, a computer. The computer may also be equipped with a display unit such as a monitor that displays various information. The computer program that operates each unit of the gas supply device 30 is stored in a storage medium. The storage medium may be, for example, a flexible disk, a compact disk, a hard disk, a flash memory, a DVD, or the like.

[0029] Next, the liquid volume monitoring unit 39 will be described with reference to Fig. 3. Fig. 3 is an example of a functional block diagram of the liquid volume monitoring unit 39.

[0030] The liquid level monitoring section 39 has a usage amount calculation section 391 , a refill amount calculation section 392 , a remaining amount calculation section 393 , a virtual sensor section 394 , a level sensor detection section 395 , and a failure determination section 396 .

[0031] The usage amount calculation unit 391 calculates the usage amount of the raw material (source gas) supplied from the raw material storage tank 32 to the processing vessel 10. For example, the usage amount calculation unit 391 calculates the usage amount from the time when the raw material is used and a coefficient related to the raw material.

[0032] The replenishment amount calculation unit 392 calculates the replenishment amount of the raw material (liquid raw material) supplied from a liquid raw material supply unit (not shown) to the raw material storage tank 32. For example, the replenishment amount calculation unit 392 calculates the replenishment amount from the replenishment flow rate. Specifically, the replenishment amount calculation unit 392 calculates the replenishment amount based on the flow rate controlled by the flow rate controller 38b and the open time (replenishment time) of the on-off valve 38c.

[0033] The remaining amount calculation unit 393 calculates the remaining amount (liquid amount) of the liquid source 31 stored in the source storage tank 32.

[0034] Here, the liquid amount monitoring unit 39 (remaining amount calculation unit 393) prestores information associating each level detection position "LL", "L", "H", and "HH" with the liquid amount when the liquid raw material 31 is stored in the raw material storage tank 32 up to each level detection position. When any of the detection sensors 35a to 35d is switched from ON state to OFF state or from OFF state to ON state, the remaining amount calculation unit 393 regards the liquid amount of the liquid raw material 31 corresponding to the switched detection sensor 35a to 35d as the remaining amount (initial remaining amount) of the liquid raw material 31 stored in the raw material storage tank 32. Thereafter, the remaining amount calculation unit 393 calculates the remaining amount based on the initial remaining amount of the liquid raw material 31, the usage amount calculated by the usage amount calculation unit 391 after the initial remaining amount was set, and the replenishment amount calculated by the replenishment amount calculation unit 392 after the initial remaining amount was set (remaining amount=initial remaining amount-used amount+replenishment amount).

[0035] The virtual sensor unit 394 estimates the detection results of virtual sensors (hereinafter also referred to as "virtual sensors") by assuming that there are virtual detection sensors at the level detection positions "LL", "L", "H", and "HH".

[0036] The liquid amount monitoring unit 39 (virtual sensor unit 394) prestores information associating each of the level detection positions "LL", "L", "H", and "HH" with the liquid amount when the liquid raw material 31 is stored in the raw material storage tank 32 up to each level detection position. The virtual sensor unit 394 estimates the detection results (ON state or OFF state) of the virtual sensor at the level detection position "LL", the virtual sensor at the level detection position "L", the virtual sensor at the level detection position "H", and the virtual sensor at the level detection position "HH" based on the remaining amount of the liquid raw material 31 calculated by the remaining amount calculation unit 393 and this information.

[0037] The level sensor detection unit 395 acquires the detection results of the level sensors 35 (detection sensors 35a to 35d, hereinafter also referred to as "actual sensors"). That is, the level sensor detection unit 395 acquires the detection results (ON state or OFF state) of the detection sensor 35a at the level detection position "LL", the detection sensor 35b at the level detection position "L", the detection sensor 35c at the level detection position "H", and the detection sensor 35d at the level detection position "HH".

[0038] The failure determination unit 396 determines whether or not the detection result of the virtual sensor estimated by the virtual sensor unit 394 matches the detection result of the actual sensor acquired by the level sensor detection unit 395. If they do not match, the failure determination unit 396 determines that the level sensor 35 (detection sensors 35a to 35d) is broken. The failure determination unit 396 also determines whether or not the level sensor 35 (detection sensors 35a to 35d) is broken based on the remaining amount (liquid amount) of the liquid source 31 stored in the source storage tank 32 calculated by the remaining amount calculation unit 393 and the detection result of the actual sensor acquired by the level sensor detection unit 395.

[0039] In this manner, the gas supply device 30 according to this embodiment can perform dual monitoring of the liquid level of the liquid raw material 31 stored in the raw material storage tank 32 by using the level sensor 35 (detection sensors 35a to 35d) which is a real sensor and the virtual sensor unit 394 which is a virtual sensor.

[0040] Furthermore, the remaining amount calculation unit 393 of the gas supply device 30 according to this embodiment can suitably calculate the remaining amount (liquid amount) of the liquid source 31 stored in the source storage tank 32 even when the liquid level is between one level detection position and another level detection position or when the liquid level is lower than the level detection position "LL". This allows the gas supply device 30 according to this embodiment to accurately monitor the remaining amount (liquid amount) of the liquid source 31.

[0041] Furthermore, the failure determination unit 396 of the gas supply device 30 according to this embodiment can determine a failure of the level sensor 35 (detection sensors 35a to 35d) by comparing the detection result of the virtual sensor with the detection result of the real sensor (detection sensors 35a to 35d). When the failure determination unit 396 determines that the level sensor 35 (detection sensors 35a to 35d) is malfunctioning, the control unit 60 causes a display unit (not shown) such as a monitor to display that fact. This can notify the operator of the malfunction of the level sensor 35 (detection sensors 35a to 35d).

[0042] When judging a failure of a level sensor 35 (detection sensor 35a-35d) using only the actual sensor (detection sensor 35a-35d), it can be judged that the target detection sensor has failed when, for example, the liquid level is below the level detection position of the target detection sensor due to sufficient use of liquid raw material 31 but the detection result of the target detection sensor remains in the ON state, or when the liquid level is above the level detection position of the target detection sensor due to sufficient replenishment of liquid raw material 31 but the detection result of the target detection sensor remains in the OFF state. For this reason, it may take some time to judge that the detection sensor has failed.

[0043] In contrast, the failure determination unit 396 of the gas supply device 30 according to this embodiment can determine a failure by comparing the detection results of the virtual sensor with the detection results of the actual sensors (detection sensors 35a to 35d), and can therefore quickly determine whether or not there is a failure in the detection sensors 35a to 35d.

[0044] Moreover, according to the gas supply device 30 of the present embodiment, the volume of the gas phase can be appropriately controlled by monitoring the liquid level, thereby improving the uniformity of substrate processing in the substrate processing apparatus.

[0045] Next, an example of the operation of the gas supply device 30 will be described with reference to FIG. 4. FIG. 4 is a graph showing an example of a change in the liquid level of the liquid source 31. In FIG. 4, the vertical axis indicates the liquid level, and the horizontal axis indicates time. "LL", "L", "H", and "HH" indicate the level detection positions where the detection sensors 35a to 35d are provided. Also, "R" indicated by the dashed line is the target liquid level (hereinafter also referred to as "reference level") when refilling the liquid source into the source storage tank 32.

[0046] By supplying the vaporized source gas to the processing vessel 10, the liquid level of the liquid source 31 gradually decreases. At time T1, it is time to replenish the liquid source. Here, the actual sensors (detection sensors 35a to 35d) are used to determine the timing of replenishment. For example, after the detection sensor 35b changes from an ON state to an OFF state, it is determined that it is time to replenish.

[0047] Here, an example of the liquid source refilling operation using the actual sensor will be described with reference to Fig. 5. Fig. 5 is a flow chart showing an example of the liquid source refilling operation.

[0048] In step S101, the control unit 60 determines whether or not it is time to replenish. If it is not time to replenish (S101: NO), the control unit 60 repeats the process of step S101. If it is time to replenish (S101: YES), the process of the control unit 60 proceeds to step S102.

[0049] In step S102, the control unit 60 starts supplying the liquid raw material. The control unit 60 controls the flow rate controller 38b to a predetermined flow rate and controls the on-off valve 38c to open, thereby supplying the liquid raw material from a liquid raw material supply unit (not shown) to the raw material storage tank 32.

[0050] In step S103, the control unit 60 judges whether or not the detection sensor 35b has detected the liquid raw material. That is, the control unit 60 judges whether or not the judgment result of the detection sensor 35b has switched from the OFF state to the ON state. If the detection sensor 35b has not detected the liquid raw material (S103: NO), the control unit 60 continues replenishing the liquid raw material by repeating the process of step S103. If the detection sensor 35b has detected the liquid raw material (S103: YES), the process of the control unit 60 proceeds to step S104.

[0051] In step S104, the control unit 60 supplies a predetermined amount of liquid raw material. Here, the predetermined flow rate is the amount of liquid raw material required to reach the reference level "R" from the level detection position "LL". The control unit 60 supplies the predetermined amount of liquid raw material based on the flow rate controlled by the flow rate controller 38b and the time. When the predetermined amount of liquid raw material has been supplied, the process of the control unit 60 proceeds to step S105.

[0052] In step S105, the control unit 60 stops the supply of the liquid raw material. That is, the control unit 60 controls the on-off valve 38c to close.

[0053] By the above process, the liquid source 31 is replenished until the liquid level reaches the reference level "R" as shown at time T1 in FIG.

[0054] Next, the liquid level of the liquid source 31 gradually decreases as the vaporized source gas is supplied to the processing vessel 10. Here, it is assumed that the detection sensor 35b fails. Specifically, it is assumed that the detection sensor 35b fails while remaining in the ON state. Therefore, at time T2, it is not determined that it is time to replenish the source gas, and further vaporized source gas is supplied to the processing vessel 10.

[0055] Here, the failure determination unit 396 can determine that the detection sensor 35b is faulty because the detection result of the detection sensor 35b remains in the ON state and the detection result of the virtual sensor at the level detection position "L" estimated by the virtual sensor unit 394 switches to the OFF state.

[0056] If the failure determination section 396 determines that the detection sensor 35b is at fault, the liquid level monitoring section 39 uses the virtual sensor at the level detection position "L" estimated by the virtual sensor section 394 to monitor the liquid level.

[0057] Through the above process, the liquid source 31 is replenished until the liquid level reaches the reference level "R" as shown at time T3 in Fig. 4. As a result, even if at least one of the detection sensors 35a to 35d breaks down, the liquid source can be replenished using the virtual sensor, and the gas supply device 30 can continue to operate. This makes it possible to reduce the downtime of the substrate processing apparatus.

[0058] Here, the control unit 60 may control the refill amount so that the remaining amount (liquid amount) of the liquid source 31 calculated by the remaining amount calculation unit 393 becomes the liquid amount at which the liquid level reaches the reference level "R".

[0059] 4, the liquid source may be replenished for each substrate processing, as shown in time period T4. In this case, control unit 60 replenishes the liquid source so that the remaining amount (liquid volume) of liquid source 31 calculated by remaining amount calculation unit 393 corresponds to the reference level "R."

[0060] Moreover, a virtual sensor may be used in place of the actual sensor to perform the liquid source refill operation according to the flow shown in FIG.

[0061] In the example shown in FIG. 4, as shown in time period T5, it may be determined whether or not it is time to replenish based on the detection result of the virtual sensor estimated by virtual sensor unit 394, and the amount of replenishment may be controlled based on the detection result of the virtual sensor estimated by virtual sensor unit 394.

[0062] FIG. 6 is an example of a display screen 600 displayed on the display unit.

[0063] Display screen 600 displays an image 610 corresponding to raw material storage tank 32, an image 621 corresponding to on-off valve 36c, an image 622 corresponding to on-off valve 37b, an image 623 corresponding to on-off valve 38c, an image 630 corresponding to level sensor 35, and a remaining amount display section 640.

[0064] An image 621 corresponding to the on-off valve 36c, an image 622 corresponding to the on-off valve 37b, and an image 623 corresponding to the on-off valve 38c are switched so that the open / closed state can be distinguished. In the example shown in Fig. 6, when an on-off valve is open, it is illustrated by adding a shaded dot.

[0065] An image 630 corresponding to the level sensor 35 includes an image 631 corresponding to the detection sensor 35a, an image 632 corresponding to the detection sensor 35b, an image 633 corresponding to the detection sensor 35c, and an image 634 corresponding to the detection sensor 35d. The images 631 to 634 are switched according to the detection state of the detection sensors 35a to 35d. In the example shown in Fig. 6, when the liquid source 31 is detected, it is illustrated by adding a shaded dot.

[0066] The images 631 to 634 may display the results of a real sensor or the results of a virtual sensor.

[0067] The remaining amount display section 640 displays the remaining amount of the liquid raw material calculated by the remaining amount calculation section 393 in a numerical value.

[0068] The gas supply device 30 has been described above, but the present disclosure is not limited to the above-described embodiments, and various modifications and improvements are possible within the scope of the gist of the present disclosure described in the claims. [Explanation of symbols]

[0069] 10 Processing vessel 30 Gas supply equipment 31 Liquid raw materials 32 Raw material storage tank 32a Tank body 32b Ceiling cover 33a Main heating section 33b Ceiling heating section 35 Level Sensor 35a~35d Detection sensor 36 Gas inlet 36a Carrier gas flow path 36b Flow controller 36c On-off valve 37 Gas outlet 37a Gas flow path 37b On-off valve 37c Flow path heater 38 Raw material inlet 38a Liquid raw material flow path 38b Flow controller 38c On-off valve 39 Liquid level monitoring unit 60 Control section 391 Usage amount calculation part 392 Replenishment amount calculation section 393 Remaining amount calculation unit 394 Virtual Sensor Section 395 Level sensor detection section 396 Failure determination section

Claims

1. a raw material storage tank for storing a liquid raw material; a liquid level detection unit that detects a liquid level of the liquid raw material stored in the raw material storage tank; a gas inlet provided in the raw material storage tank and connected to a carrier gas supply unit that supplies a carrier gas for transporting a raw material gas to the raw material storage tank; a gas outlet provided in the raw material storage tank and connected to a gas outlet portion through which the raw material gas flows out of the raw material storage tank together with the carrier gas; a raw material inlet provided in the raw material storage tank and connected to a liquid raw material supply unit that supplies the liquid raw material to the raw material storage tank, comprising: calculating a remaining amount of the liquid source based on a usage amount of the source and a replenishment amount of the source; estimating a detection result of a virtual sensor from the calculated remaining amount of the liquid raw material; and monitoring the liquid source based on a detection result of the liquid level detection unit and an estimated detection result of the virtual sensor. Liquid raw material monitoring method.

2. The amount of the raw material used is calculated from the time when the raw material is used and a coefficient related to the raw material.

2. The method of claim 1 .

3. The replenishment amount of the raw material is calculated based on the flow rate and replenishment time of the raw material.

2. The method of claim 1 .

4. the remaining amount of the liquid raw material is calculated based on an initial remaining amount, the usage amount, and the replenishment amount; 2. The method of claim 1 .

5. and determining that the liquid level detection unit has failed when the detection result of the liquid level detection unit does not match the detection result of the estimated virtual sensor.

2. The method of claim 1 .

6. a raw material storage tank for storing a liquid raw material; a liquid level detection unit that detects a liquid level of the liquid raw material stored in the raw material storage tank; a gas inlet provided in the raw material storage tank and connected to a carrier gas supply unit that supplies a carrier gas for carrying a raw material gas to the raw material storage tank; a gas outlet provided in the raw material storage tank and connected to a gas outlet portion through which the raw material gas flows from the raw material storage tank together with the carrier gas; a raw material inlet provided in the raw material storage tank and connected to a liquid raw material supply unit that supplies the liquid raw material to the raw material storage tank; A liquid level monitoring unit, The liquid level monitoring unit is A usage amount calculation unit that calculates the usage amount of the raw material; A replenishment amount calculation unit that calculates a replenishment amount of the raw material; a remaining amount calculation unit for calculating a remaining amount of the liquid raw material; a virtual sensor unit that estimates a detection result of a virtual sensor from the calculated remaining amount of the liquid raw material; a failure determination unit that monitors the liquid source based on a detection result of the liquid level detection unit and an estimated detection result of the virtual sensor. Gas supply equipment.

Images