Material supply device, substrate processing system, and remaining amount estimation method
The raw material supply device accurately estimates the remaining amount using pressure gauges and a bypass path configuration, addressing the imprecision in conventional methods and ensuring stable supply.
Patent Information
- Application Number
- JP2021147147
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2021-09-09
- Publication Date
- 2026-01-21
- Estimated Expiration
- 2041-09-09
AI Technical Summary
Conventional raw material supply devices face challenges in accurately estimating the remaining amount of raw materials due to the high cost and limited durability of sensors, leading to imprecise timing for container replacement.
A raw material supply device with a configuration that includes a raw material container, upstream and downstream paths, a bypass path, and pressure gauges to estimate the remaining amount based on pressure detection values during gas flow, utilizing a remaining amount estimation unit to calculate the material level accurately.
Enables precise estimation of the remaining raw material amount, ensuring stable and efficient supply to the processing container.
Smart Images

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Abstract
Description
[Technical Field]
[0001] The present disclosure relates to a raw material supply device, a substrate processing system, and a remaining amount estimation method. [Background technology]
[0002] Patent Document 1 discloses a raw material supply device that circulates a carrier gas through a raw material container that contains a raw material, and supplies a gas containing the carrier gas and a raw material gas from the raw material container to a processing container.
[0003] It is difficult to install a remaining amount sensor for detecting the remaining amount of raw material in this type of source container due to reasons such as cost, durability, etc. Therefore, conventional source supply devices estimate the remaining amount of raw material in the source container based on the processing period of the substrate processing apparatus to which the source container is connected or the number of times the source gas is supplied (the number of processes) from the source container, and notify the timing of replacing the source container. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-162139 Summary of the Invention [Problem to be solved by the invention]
[0005] The present disclosure provides a technique that can accurately estimate the remaining amount of raw material in a raw material container. [Means for solving the problem]
[0006] According to one aspect of the present disclosure, there is provided a raw material container containing a solid or liquid raw material, an upstream path connected to the raw material container and capable of flowing a carrier gas, a downstream path connected to the raw material container and capable of flowing a gas containing a raw material gas generated from the raw material, a bypass path connecting the upstream path and the downstream path without passing through the raw material container and flowing the carrier gas from the upstream path to the downstream path, a downstream valve opening and closing a flow path of the downstream path, and a valve connecting the upstream path and the downstream path. both and the pressure in the upstream or downstream path is each a pressure gauge for detecting the pressure; a pressure detection value of the pressure gauge in the upstream path, and a pressure detection value of the pressure gauge in the downstream path; and a remaining amount estimation unit configured to estimate a remaining amount of the raw material in the raw material container based on the pressure detection value that decreases when the downstream valve is opened at the time when the raw material gas starts to flow from the raw material container to the downstream path. death , The remaining amount estimation unit estimates the remaining amount of the raw material in the raw material container using both the pressure detection value of the pressure gauge in the upstream path and the pressure detection value of the pressure gauge in the downstream path. , a raw material supply device is provided. [Effects of the Invention]
[0007] According to one aspect, the remaining amount of raw material in the raw material container can be estimated with high accuracy. [Brief explanation of the drawings]
[0008] [Figure 1] 1 is a schematic explanatory diagram illustrating a configuration of a substrate processing system according to an embodiment; [Figure 2] FIG. 2 is a schematic explanatory diagram showing the configuration of a raw material container and its surroundings. [Figure 3] FIG. 2 is a block diagram showing functional parts of a supply control unit. [Figure 4] FIG. 4 is a schematic explanatory diagram showing an operation procedure at the start of supplying a source gas. [Figure 5] 5(a) is a graph showing a change in the pressure detection value of the first upstream pressure gauge at the start of supplying the source gas from the first source container, and FIG. 5(b) is a graph showing an approximate curve of a change in the pressure difference of the first upstream pressure gauge with respect to the number of times the source gas is supplied. [Figure 6]6(a) is a graph showing a change in the pressure detection value of the first downstream pressure gauge at the start of supplying the source gas from the first source container, and FIG. 6(b) is a graph showing an approximate curve of a change in the pressure difference of the first downstream pressure gauge with respect to the number of times the source gas is supplied. [Figure 7] 10 is a flowchart showing a process flow of a method for estimating the remaining amount of a first raw material container. [Figure 8] Fig. 8(a) is a schematic explanatory diagram showing a raw material container and a heating unit of a raw material supplying device according to a modified example, and Fig. 8(b) is a timing chart illustrating an operation pattern of the heating unit. [Figure 9] 10 is a flowchart showing an example of a processing flow of a remaining capacity estimation method according to a modified example. DETAILED DESCRIPTION OF THE INVENTION
[0009] Hereinafter, embodiments 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 redundant explanations may be omitted.
[0010] 1 is a schematic explanatory diagram illustrating the configuration of a substrate processing system 1 according to one embodiment. As shown in FIG. 1, the substrate processing system 1 includes a substrate processing apparatus 10 that processes semiconductor wafers (hereinafter simply referred to as wafers W), which are an example of substrates, and a raw material supply apparatus 20 that supplies gases used during processing to the substrate processing apparatus 10.
[0011] The substrate processing apparatus 10 is a semiconductor manufacturing apparatus such as a film formation apparatus. The substrate processing apparatus 10 includes a processing chamber 11 and a main control unit 15. When the substrate processing apparatus 10 is, for example, a film formation apparatus, the substrate processing apparatus 10 performs a film formation process on a wafer W accommodated in the processing chamber 11.
[0012] The processing vessel 11 is made of an aluminum alloy or the like and has a cylindrical shape. An opening is formed in the sidewall of the processing vessel 11 for loading and unloading the wafer W into and out of the processing vessel 11, and a gate valve is provided at the opening for opening and closing the opening (both not shown). A mounting table 12 for mounting the wafer W thereon is provided inside the processing vessel 11. The mounting table 12 has a chuck device for fixing the wafer W and a temperature adjustment unit for adjusting the temperature of the wafer W (both not shown).
[0013] An exhaust path 13 that exhausts gas from the processing vessel 11 is connected to the processing vessel 11. A pressure adjustment valve, a vacuum pump, and the like are provided on the exhaust path 13 (both not shown). Furthermore, one end of a supply path 14 that supplies gas is connected to the processing vessel 11. The other end of the supply path 14 is connected to a raw material supply device 20. That is, the processing vessel 11 and the raw material supply device 20 of the substrate processing apparatus 10 are in communication with each other via the supply path 14.
[0014] The raw material supply apparatus 20 has multiple (two in FIG. 1 ) raw material containers 21. Hereinafter, one of the multiple raw material containers 21 will be referred to as a first raw material container 21A, and the other will be referred to as a second raw material container 21B. The raw material supply apparatus 20 also has a heating unit 30 that heats each raw material container 21, a carrier gas supply mechanism 40 that supplies a carrier gas to each raw material container 21, and a supply control unit 90 that controls each component of the raw material supply apparatus 20. The supply path 14, each raw material container 21, and the carrier gas supply mechanism 40 are interconnected by multiple gas paths 50. Furthermore, the raw material supply apparatus 20 has multiple on-off valves 60 in the gas paths 50 around the raw material containers 21.
[0015] FIG. 2 is a schematic diagram illustrating the configuration of the source container 21 (first source container 21A) and its surroundings. As shown in FIGS. 1 and 2, the source container 21 may be a tank that contains multiple source materials M and can vaporize (sublimate) the source materials M by heating using a heating unit 30. The source material M in the source container 21 is not particularly limited, and examples thereof include chloride compounds such as aluminum chloride (AlCl) and copper chloride (AlCu). Alternatively, the source material M may be metal organics such as Si, Hf, Ta, Zr, Al, Ti, Zn, In, Ga, or P, or other solid or liquid source materials. In this embodiment, a case where aluminum chloride is used as the solid source material M will be described. Note that the term "vaporization" in this embodiment encompasses both the sublimation of a solid source material into a gas and the evaporation of a liquid source material into a gas.
[0016] The raw material M in the first raw material container 21A and the raw material M in the second raw material container 21B may be the same type of raw material M or different types of raw material M. Although FIG. 1 shows an example with two raw material containers 21, the raw material supply device 20 may be configured with one raw material container 21, or three or more raw material containers 21. Below, the first raw material container 21A and its surrounding structure will be described in detail, and the second raw material container 21B and its surrounding structure will be omitted as appropriate because they are formed in the same manner as the first raw material container 21A.
[0017] 2, the first raw material container 21A is formed in a cylindrical or rectangular tubular shape extending in the vertical direction. A plurality of trays 22 are provided in the first raw material container 21A at approximately equal intervals in the vertical direction. One or more raw materials M are placed on each tray 22.
[0018] The first source material container 21A is made of a material with high thermal conductivity (such as alumina). A heating unit 30 (first heating unit 30A) for heating the first source material container 21A is provided outside the first source material container 21A or on the peripheral wall of the container. The first heating unit 30A heats the source material M in the first source material container 21A under the control of the supply control unit 90. For example, an electric heater such as a sheath heater or a hand heater can be used as the first heating unit 30A.
[0019] The carrier gas supply mechanism 40 selectively supplies a carrier gas to a gas path 50 (first gas path 50A) connected to the first source material container 21A and a gas path 50 (second gas path 50B) connected to the second source material container 21B. Examples of the carrier gas include inert gases such as argon gas (Ar gas), helium gas (He gas), and nitrogen gas (N gas). For example, the carrier gas supply mechanism 40 includes a carrier gas supply source, a regulator that reduces the pressure of the carrier gas delivered from the supply source, and a valve that opens or closes the flow path of each gas path 50 (all not shown).
[0020] The first gas path 50A includes a first upstream path 51A connecting the carrier gas supply mechanism 40 and the first raw material container 21A, a first downstream path 52A connecting the first raw material container 21A and the supply path 14, and a first bypass path 53A bypassing the first raw material container 21A. That is, the raw material supply device 20 forms a primary side through which the carrier gas flows into the first raw material container 21A via the first upstream path 51A, and a secondary side through which the vaporized raw material gas flows out together with the carrier gas via the first downstream path 52A. The first bypass path 53A connects the first upstream path 51A and the first downstream path 52A.
[0021] The on-off valves 60 around the first raw material container 21A include a first upstream valve 61A provided in the first upstream path 51A, a first downstream valve 62A provided in the first downstream path 52A, and a first bypass valve 63A provided in the first bypass path 53A. The first upstream valve 61A is provided downstream (toward the first raw material container 21A) of the connection point of the first upstream path 51A and the first bypass path 53A. The first downstream valve 62A is provided upstream (toward the first raw material container 21A) of the connection point of the first bypass path 53A on the first downstream path 52A.
[0022] Each on-off valve 60 is connected to a supply control unit 90, and opens (fully opens) or closes (fully closes) the flow path of each route based on the control of the supply control unit 90. Each on-off valve 60 allows gas to flow through the flow path in the open state, and blocks the flow of gas in the flow path in the closed state.
[0023] Furthermore, the first upstream path 51A has a mass flow controller 54 and a pressure gauge 70 (first upstream pressure gauge 70A) in addition to the first upstream valve 61A. The first upstream path 51A may also include a safety valve, a constant pressure valve, a filter, a heater, etc.
[0024] The mass flow controller 54 is provided on the first upstream path 51A upstream of the connection point of the first bypass path 53A (on the carrier gas supply mechanism 40 side), and is connected to the supply control unit 90. Under the control of the supply control unit 90, the mass flow controller 54 adjusts the flow rate of the carrier gas supplied from the carrier gas supply mechanism 40 to the first source material container 21A.
[0025] The first upstream pressure gauge 70A is provided between the mass flow controller 54 and the first upstream valve 61A (and the connection point of the first bypass path 53A). The first upstream pressure gauge 70A detects the internal pressure (carrier gas pressure) of the flow path of the piping that constitutes the first upstream path 51A, and transmits information on the detected pressure value to the supply control unit 90. Various detectors that can detect total pressure (static pressure, dynamic pressure) can be used as the first upstream pressure gauge 70A. The first upstream pressure gauge 70A may be provided on the first upstream path 51A upstream of the mass flow controller 54.
[0026] The first downstream path 52A has a pressure gauge 70 (first downstream pressure gauge 71A) in addition to the first downstream valve 62A. The first downstream pressure gauge 71A is provided downstream of the first downstream valve 62A (and the connection point of the first bypass path 53A). The first downstream pressure gauge 71A detects the internal pressure (pressure of the carrier gas and the source gas) of the flow path of the piping that constitutes the first downstream path 52A, and transmits information on the detected pressure value to the supply control unit 90.
[0027] Returning to FIG. 1 , the gas path 50 of the raw material supply device 20 further includes a first branch path 55 branching off from the first upstream path 51A. The other end of the first branch path 55 is connected to the first downstream path 52A between the first downstream valve 62A and the first downstream pressure gauge 71A. A mass flow controller 56 is provided midway along the first branch path 55. The mass flow controller 56 adjusts the flow rate of the carrier gas flowing from the first upstream path 51A to the first downstream path 52A via the first branch path 55.
[0028] The raw material supplying device 20 has the same configuration around the second raw material container 21B as the configuration around the first raw material container 21A. That is, the heating unit 30 has a second heating unit 30B that heats the second raw material container 21B.
[0029] The second gas path 50B includes a second upstream path 51B connecting the carrier gas supply mechanism 40 and the second raw material container 21B, a second downstream path 52B connecting the second raw material container 21B and the supply path 14, and a second bypass path 53B that bypasses the second raw material container 21B. The on-off valve 60 around the second raw material container 21B includes a second upstream valve 61B provided in the second upstream path 51B, a second downstream valve 62B provided in the second downstream path 52B, and a second bypass valve 63B provided in the second bypass path 53B.
[0030] The second upstream path 51B has a mass flow controller 57 and a second upstream pressure gauge 70B in addition to the second upstream valve 61B. The second downstream path 52B has a second downstream pressure gauge 71B in addition to the first downstream valve 62A. Furthermore, the raw material supply device 20 has a second branch path 58 branching from the second upstream path 51B and connected to the second downstream path 52B between the second downstream valve 62B and the second downstream pressure gauge 71B. A mass flow controller 59 is provided midway along the second branch path 58.
[0031] In the substrate processing system 1 having the above-described substrate processing apparatus 10 and raw material supply apparatus 20, the operation of the entire system is controlled by a main control unit 15 of the substrate processing apparatus 10. A supply control unit 90 of the raw material supply apparatus 20 is connected to the main control unit 15 via an appropriate communication means 16 and operates based on commands from the main control unit 15 to control the operation of the raw material supply apparatus 20. The communication means 16 may employ either wired or wireless communication, and may be configured to directly connect the control units to each other or may be configured to use a network such as a local area network (LAN). Note that the substrate processing system 1 may be configured such that the main control unit 15 has the function of the supply control unit 90, but does not include the supply control unit 90.
[0032] The main control unit 15 has a controller main body 17 that controls the entire substrate processing system 1, and a user interface 18 that is connected to the controller main body 17. The controller main body 17 and the supply control unit 90 are configured by a computer, a control circuit board, etc.
[0033] For example, the controller main body 17 has a processor, a memory, an input / output interface, and an electronic circuit (all not shown). The processor executes a program recorded in the memory, whereby the controller main body 17 transmits and receives various signals to and from each component of the substrate processing system 1, thereby carrying out substrate processing.
[0034] The user interface 18 may be, for example, a keyboard through which a user inputs commands, or a display that visualizes and displays the operating status of the substrate processing system 1. Alternatively, the user interface 18 may be a device such as a touch panel, a mouse, a microphone, or a speaker.
[0035] The supply control unit 90 also has one or more processors 91, a memory 92, an input / output interface (not shown), and electronic circuits. The processor 91 is one or a combination of a CPU, an ASIC, an FPGA, and a circuit made up of multiple discrete semiconductors. The memory 92 includes volatile memory and non-volatile memory (e.g., a compact disc, a DVD, a hard disk, a flash memory, etc.), and stores a program for operating the raw material supply device 20 and recipes such as process conditions.
[0036] Fig. 3 is a block diagram showing the functional parts of the supply control unit 90. The supply control unit 90 forms a supply operation control unit 95, a pressure acquisition unit 96, and a remaining amount estimation unit 97 by having a processor 91 execute programs and recipes stored in a memory 92, as shown in Fig. 3.
[0037] The supply operation control unit 95 operates based on receiving a supply command from the controller main body 17, transmits and receives various signals to and from each component of the raw material supply device 20, and supplies gas to the substrate processing apparatus 10. The pressure acquisition unit 96 detects pressure using the pressure gauges 70 (first upstream pressure gauge 70A, second upstream pressure gauge 70B, first downstream pressure gauge 71A, and second downstream pressure gauge 71B), acquires the detected pressure values, and stores them in the memory 92.
[0038] The remaining amount estimation unit 97 performs a remaining amount estimation method for estimating the remaining amount of the raw material M in the raw material container 21. That is, the processor 91 of the supply control unit 90 has a function of estimating the remaining amount of the raw material M in the raw material container 21. Note that the substrate processing system 1 may include the remaining amount estimation unit 97 in the main control unit 15.
[0039] When estimating the remaining amount of raw material M in the first source container 21A, the remaining amount estimation unit 97 uses the pressure detection value of the first upstream pressure gauge 70A or the pressure detection value of the first downstream pressure gauge 71A acquired by the pressure acquisition unit 96. Since the first upstream pressure gauge 70A and the first downstream pressure gauge 71A can be detectors typically installed to monitor the pressure in the gas path 50, a separate component for estimating the remaining amount of raw material M is not required. The remaining amount estimation unit 97 estimates the remaining amount of raw material M in the first source container 21A based on the detected pressure drop that occurs when the first downstream valve 62A is opened at the start of the supply of the source gas. A specific method for estimating the remaining amount of raw material M will be described in detail later. It goes without saying that the remaining amount estimation unit 97 can also estimate the remaining amount of raw material M in the second source container 21B using a method similar to that for the first source container 21A.
[0040] The substrate processing system 1 and the raw material supply device 20 according to this embodiment are basically configured as described above, and their operation will be described below.
[0041] The main control unit 15 of the substrate processing apparatus 10 transmits a supply command to the supply control unit 90 to supply the source gas to the processing chamber 11 at an appropriate timing when processing the wafer W (for example, after the wafer W has been placed on the mounting table 12 and the processing chamber 11 has been depressurized). Upon receiving this supply command, the supply control unit 90 controls each component of the source gas supply device 20 by the supply operation control unit 95 to start supplying the source gas.
[0042] 2 and 3, when the supply of the raw material gas starts (or after the raw material supply device 20 is started), the supply operation control unit 95 operates the first heating unit 30A and the second heating unit 30B to heat the first raw material container 21A and the second raw material container 21B. As a result, the raw material M in the first raw material container 21A is heated to a temperature at which it can be vaporized, and the raw material M in the second raw material container 21B is heated to a temperature at which it can be vaporized.
[0043] 4 is a schematic diagram illustrating the operation procedure when the supply of the source gas is started. FIG. 4(a) shows the state before the supply starts, FIG. 4(b) shows the first state after the supply starts, FIG. 4(c) shows the second state after the first state, FIG. 4(d) shows the third state after the second state, and FIG. 4(e) shows the fourth state in which the source gas is continuously supplied after the third state. As shown in FIG. 4, the supply operation control unit 95 adjusts the timing of opening and closing the three on-off valves 60 when the source gas is supplied from the first source container 21A.
[0044] 4(a), before the start of the supply of the source gas, the source gas supply apparatus 20 closes the first upstream valve 61A, the second upstream valve 61B, and the first bypass valve 63A. The supply operation control unit 95 also stops the supply of the carrier gas from the carrier gas supply mechanism 40 to the first gas path 50A. Upon receiving a command to start the supply of the source gas, the supply operation control unit 95 starts the supply of the carrier gas from the carrier gas supply mechanism 40 to the first gas path 50A. The carrier gas supplied from the carrier gas supply mechanism 40 flows from the first upstream path 51A through the first branch path 55. The flow rate of the carrier gas is adjusted by the mass flow controller 56 of the first branch path 55. The carrier gas flows from the first branch path 55 to the first downstream path 52A and is then supplied to the processing chamber 11 via the supply path 14.
[0045] Then, with the carrier gas flowing through the first branch path 55, the supply operation control unit 95 first opens only the first bypass side valve 63A, as shown in FIG. 4(b). As a result, the carrier gas supplied from the carrier gas supply mechanism 40 is distributed to the first upstream path 51A and the first branch path 55 under the control of the mass flow controllers 54 and 56. The carrier gas flowing into the first upstream path 51A passes through the first bypass path 53A from the first upstream path 51A and flows into the first downstream path 52A. The carrier gas then merges with the carrier gas flowing through the first branch path 55 in the first downstream path 52A, flows toward the supply path 14, and is supplied to the processing vessel 11 via the supply path 14. The supply operation control unit 95 maintains this first state, in which only the first bypass side valve 63A is opened, for a predetermined period (e.g., one second).
[0046] 4(c), the supply operation control unit 95 opens the first downstream valve 62A while continuing to supply the carrier gas from the carrier gas supply mechanism 40 to the first gas path 50A and opening the first bypass valve 63A. As a result, the source gas vaporized from the source material M in the first source material container 21A flows into the first downstream path 52A and is mixed with the carrier gas flowing through the first downstream path 52A. This mixed gas is supplied to the processing vessel 11 via the supply path 14. The internal pressure of the first source material container 21A decreases as the vaporized source gas flows out. The supply operation control unit 95 maintains this second state, in which the first downstream valve 62A and the first bypass valve 63A are opened, for a predetermined period (e.g., one second).
[0047] 4(d), the supply operation control unit 95 opens the first upstream valve 61A while continuing to supply the carrier gas from the carrier gas supply mechanism 40 to the first gas path 50A and keeping the first downstream valve 62A and the first bypass valve 63A open. As a result, part of the carrier gas flows from the first upstream path 51A to the first source material container 21A, and the other part of the carrier gas flows from the first upstream path 51A to the first downstream path 52A via the first bypass path 53A. In other words, the pressure of the carrier gas is divided according to the pressure in the first source material container 21A.
[0048] The carrier gas flowing into the first source container 21A is mixed with the source gas to form a mixed gas, which flows out to the first downstream path 52A and is further mixed into the carrier gas in the first downstream path 52A. The mixed gas is then supplied to the processing container 11 via the supply path 14. The supply operation control unit 95 maintains the third state in which the first upstream valve 61A, the first downstream valve 62A, and the first bypass valve 63A are opened for a predetermined period (e.g., one second).
[0049] 4(e), the supply operation control unit 95 closes the first bypass valve 63A while continuing to supply the carrier gas from the carrier gas supply mechanism 40 to the first gas path 50A and keeping the first upstream valve 61A and the first downstream valve 62A open. As a result, all of the carrier gas from the first upstream path 51A flows into the first source container 21A and mixes with the source gas in the first source container 21A. This mixed gas flows from the first source container 21A to the first downstream path 52A and is supplied to the processing container 11 via the first downstream path 52A and the supply path 14. The supply operation control unit 95 maintains this fourth state, in which the first upstream valve 61A and the first downstream valve 62A are open, throughout the processing period for processing the wafer W.
[0050] By controlling the above-described on-off valves 60, the raw material supply device 20 can suppress a sudden increase or decrease in pressure in the first raw material container 21A or the first gas path 50A when starting to supply the raw material gas. As a result, the raw material supply device 20 can stably supply the carrier gas and the raw material gas to the processing container 11.
[0051] Next, a method for estimating the remaining amount of raw material M in the raw material container 21 using the pressure detection value of the first upstream pressure gauge 70A or the pressure detection value of the first downstream pressure gauge 71A will be described. Fig. 5(a) is a graph showing the change in the pressure detection value of the first upstream pressure gauge 70A at the start of supplying the raw material gas to the first raw material container 21A, where the horizontal axis represents time and the vertical axis represents the pressure detection value of the first upstream pressure gauge 70A.
[0052] The multiple curves of the pressure detection values shown in the graph of FIG. 5(a) each represent a different number of times that the source gas is supplied from the first source container 21A to the processing container 11 by operating the source supply device 20. That is, the number of times of supply increases as the curve goes from thick to thin. Specifically, the thickest curve represents 364 times of supply, and the thinnest curve represents 424 times of supply. The other curves represent appropriate numbers of supply between 364 and 424 times.
[0053] In the graph of FIG. 5(a), start time t0 is the timing when the supply state changes from before the start of supply shown in FIG. 4(a) to the first state shown in FIG. 4(b) (start time of the first state). Time t1 is one second after start time t0 and is the timing when the supply state changes from the first state to the second state shown in FIG. 4(c) (start time of the second state). Time t2 is two seconds after start time t0 and is the timing when the supply state changes from the second state to the third state shown in FIG. 4(d) (start time of the third state). Time t3 is three seconds after start time t0 and is the timing when the supply state changes from the third state to the fourth state shown in FIG. 4(e) (start time of the fourth state).
[0054] 5(a), the pressure detection value of the first upstream pressure gauge 70A decreases from the start time t0 after the start of supply until time t3, reaches a minimum value around time t3, and then starts to increase. Furthermore, after time t3, the pressure detection value of the first upstream pressure gauge 70A increases and then decreases (after overshooting), and then gradually increases.
[0055] Furthermore, the pressure detection value of the first upstream pressure gauge 70A increases little by little each time the number of times the source gas is supplied from the first source container 21A increases. This is because the mass flow controllers 54, 56 increase the flow rate of the carrier gas flowing through the first upstream path 51A relative to the flow rate of the carrier gas flowing through the first branch path 55 each time the number of times the source gas is supplied increases. This ensures the supply rate of the source gas flowing out of the first source container 21A even if the remaining amount of source gas in the first source container 21A decreases.
[0056] The pressure detection value of the first upstream pressure gauge 70A decreases from the start time t0 to time t3, and the graph shows that the amount of decrease (absolute value) of the pressure detection value increases as the number of times the source gas is supplied increases. That is, the dark-colored curve indicating a small number of times the source gas is supplied decreases little, while the light-colored curve indicating a large number of times the source gas is supplied decreases much (see the arrows in FIG. 5(a)). A small number of times the source gas is supplied indicates a state in which the remaining amount of source material M is large, and a large number of times the source gas is supplied indicates a state in which the remaining amount of source material M is small. Therefore, the remaining amount estimation unit 97 can estimate the remaining amount of source material M in the first source container 21A by monitoring the decreasing trend of the pressure detection value of the first upstream pressure gauge 70A at the start of supplying the source gas from the first source container 21A.
[0057] For example, the remaining amount estimation unit 97 extracts the pressure detection value of the first upstream pressure gauge 70A at the start time t0 and the pressure detection value of the first upstream pressure gauge 70A at time t2, and calculates the pressure difference, which is the difference between them. The pressure difference between the pressure detection value at start time t0 and the pressure detection value at time t2 indicates the negative decrease in the pressure detection value from the start of supply until two seconds have elapsed (from three seconds to one second before the on-off valve 60 is opened as shown in FIG. 4(e)). The absolute value of this negative decrease corresponds to the amount of decrease. If the negative decrease value, which is the pressure difference, is large (the amount of decrease is small), the remaining amount of raw material M in the first raw material container 21A is large, and if the negative decrease value, which is the pressure difference, is small (the amount of decrease is large), the remaining amount of raw material M in the first raw material container 21A is small. Therefore, when the calculated pressure difference is large, the remaining amount estimation unit 97 can estimate that the remaining amount of raw material M in the first raw material container 21A is large, and when the calculated pressure difference is small, the remaining amount estimation unit 97 can estimate that the remaining amount of raw material M in the first raw material container 21A is small.
[0058] 5(b) is a graph showing, as an approximation curve, the change in the pressure difference of the first upstream pressure gauge 70A versus the number of times the source gas is supplied, with the horizontal axis representing the number of times the source gas is supplied and the vertical axis representing the pressure difference. As shown in FIG. 5(b), the approximation curve of the pressure difference of the first upstream pressure gauge 70A gradually decreases when the number of times the source gas is supplied is small and decreases significantly when the number of times the source gas is supplied is large. This is thought to be because, as the remaining amount of source material M in the first source container 21A decreases, the surface area of the source material M itself decreases, which reduces the amount of source gas vaporized from the source material M and causes a decrease in the internal pressure of the source container 21.
[0059] Therefore, in the remaining amount estimation method, an approximate curve such as that shown in FIG. 5(b) is obtained through experiments or simulations. Map information IA (see FIG. 3) or a function is created based on this approximate curve and stored in the storage unit 97a (memory 92) of the remaining amount estimation unit 97. For example, map information IA correlates the pressure difference between the pressure detection values and the remaining amount of raw material M in the first source container 21A based on the weight and volume of the raw material M. Since the vaporization (sublimation) amount of raw material M in the first source container 21A is affected not only by the remaining amount of raw material M but also by the vaporization time and the temperature of the first heating unit 30A, the map information is created based on data in which the vaporization time and temperature conditions are controlled. Alternatively, the remaining amount estimation unit 97 may have multiple map information IA for multiple temperature ranges and vaporization times of the source container 21. Map information IA prepared in this manner can be reused as long as the device, raw material M, and component configuration of the source container 21 remain the same.
[0060] However, when estimating the remaining amount of raw material M, the supply control unit 90 controls the vaporization conditions (pressure and temperature of the first source container 21A) for vaporizing the raw material M so that they are the same. For example, to make the vaporization conditions the same, the supply operation control unit 95 may reset the vaporization state of the raw material M in the first source container 21A by opening the first upstream valve 61A and the first downstream valve 62A around the first source container 21A before the estimation. Note that if the vaporization conditions are not the same due to factors such as the environment of the factory where the substrate processing system 1 is installed, the supply control unit 90 may decide not to perform the remaining amount estimation method.
[0061] The remaining amount estimating unit 97 calculates the pressure difference between the pressure detection values of the first upstream pressure gauge 70A at the start of the supply of the source gas, and then refers to the stored map information IA to obtain the remaining amount of source material M in the first source container 21A. As shown in the graph of FIG. 5(a), the pressure detection value of the first upstream pressure gauge 70A may contain errors due to factors other than changes in the number of supplies. For this reason, the remaining amount estimating unit 97 may obtain the remaining amount of source material M in the first source container 21A using an average (moving average) of the pressure detection values from the current supply number to a predetermined number of supplies ago.
[0062] 6(a) is a graph showing changes in the pressure detection value of the first downstream pressure gauge 71A at the start of supply of the source gas from the first source container 21A, where the horizontal axis represents time and the vertical axis represents the pressure detection value of the first downstream pressure gauge 71A. Similar to the graph of FIG. 5(a), the curves of the multiple pressure detection values shown in the graph of FIG. 6(a) each represent a different number of times the source gas is supplied from the first source container 21A to the processing container 11. That is, the number of times the supply increases as the curve changes from thick to thin. Furthermore, in the graph of FIG. 6(a), the period from start time t0 to time t3 corresponds to the process in which each opening / closing valve 60 is operated from before the supply starts to the fourth state.
[0063] As shown in FIG. 6A, the pressure measurement value of the first downstream pressure gauge 71A decreases from the start time t0 to time t3 after the start of supply, reaches a minimum value at time t3 or several seconds after time t3, and then begins to rise rapidly. Furthermore, after approximately 8 seconds have passed since the start time t0, the pressure measurement value of the first downstream pressure gauge 71A gradually increases. Note that, after 8 seconds have passed since the start time t0, the pressure measurement value of the first downstream pressure gauge 71A remains substantially constant regardless of the number of times the source gas is supplied. This is because the first downstream pressure gauge 71A is located downstream of the junction of the first branched path 55 in the first downstream path 52A, and the carrier gas distributed to the first upstream path 51A and the first branched path 55 merge, stabilizing the pressure.
[0064] It can also be seen that, from the start time t0 to time t3, the decrease (absolute value) in the pressure detection value of the first downstream pressure gauge 71A increases as the number of times the source gas is supplied increases. That is, the decrease in the pressure detection value of the thick curve corresponding to a small number of times the source gas is supplied is small, while the decrease in the pressure detection value of the thin curve corresponding to a large number of times the source gas is supplied is large (see the arrows in FIG. 6(a)). Therefore, the remaining amount estimation unit 97 can estimate the remaining amount of source material M in the first source container 21A by monitoring the decreasing trend in the pressure detection value of the first downstream pressure gauge 71A at the start of supplying the source gas from the first source container 21A.
[0065] For example, similar to the case of the pressure detection value of the first upstream pressure gauge 70A, the remaining amount estimation unit 97 extracts the pressure detection value of the first downstream pressure gauge 71A at the start time t0 and the pressure detection value of the first downstream pressure gauge 71A at time t2, and calculates the pressure difference (negative decrease value) that is the difference between them. If this pressure difference is large, the remaining amount of raw material M in the first raw material container 21A is large, and if this pressure difference is small, the remaining amount of raw material M in the first raw material container 21A is small. Therefore, if the calculated pressure difference is large, the remaining amount estimation unit 97 can estimate that the remaining amount of raw material M in the first raw material container 21A is large, and if the calculated pressure difference is small, the remaining amount estimation unit 97 can estimate that the remaining amount of raw material M in the first raw material container 21A is small.
[0066] FIG. 6(b) is a graph showing the change in the pressure difference of the first downstream pressure gauge 71A versus the number of times the source gas is supplied, using an approximate curve. The horizontal axis represents the number of times the source gas is supplied, and the vertical axis represents the pressure difference. As shown in FIG. 6(b), the approximate curve of the pressure difference of the first downstream pressure gauge 71A also gradually decreases when the number of times the source gas is supplied is small, and decreases significantly when the number of times the source gas is supplied is large. Therefore, the remaining amount estimation unit 97 obtains an approximate curve such as that shown in FIG. 6(b) through experiments, simulations, etc., and stores map information IB (see FIG. 3) or a function based on this approximate curve. The remaining amount estimation unit 97 then calculates the pressure difference of the pressure detection values of the first downstream pressure gauge 71A at the start of the source gas supply, and can obtain the remaining amount of source material M in the first source container 21A by referring to the stored map information IB.
[0067] The pressure detection value of the first downstream pressure gauge 71A also generates an error due to factors other than the change in the number of supplies. Therefore, the remaining amount estimation unit 97 may calculate the remaining amount of raw material M in the first raw material container 21A using an average value (moving average) of the pressure detection values from the current number of supplies to a predetermined number of supplies before.
[0068] The remaining amount estimating unit 97 can estimate the remaining amount of raw material M in the first raw material container 21A using only one of the pressure difference between the pressure detection values of the first upstream pressure gauge 70A and the pressure difference between the pressure detection values of the first downstream pressure gauge 71A, but preferably uses both. For example, the remaining amount estimating unit 97 can estimate the remaining amount of raw material M in the first raw material container 21A by calculating the average value of the pressure difference between the pressure detection values of the first upstream pressure gauge 70A and the pressure difference between the pressure detection values of the first downstream pressure gauge 71A and referring to map information (not shown) corresponding to the average value. Alternatively, the remaining amount estimating unit 97 may first calculate the remaining amount of raw material M in the first raw material container 21A using one of the pressure difference between the pressure detection values of the first upstream pressure gauge 70A and the pressure difference between the pressure detection values of the first downstream pressure gauge 71A, and then correct the calculated remaining amount using the other.
[0069] 7 is a flowchart showing a process flow of the method for estimating the remaining amount of the first source material container 21A. Hereinafter, the process flow of the method for estimating the remaining amount of the first source material container 21A, which is a summary of the above processes of the substrate processing system 1, will be described with reference to FIG.
[0070] In carrying out the remaining amount estimation method, the supply control unit 90 of the raw material supply device 20 starts supplying the raw material gas from the first raw material container 21A using the supply operation control unit 95. In the supply start process, the supply operation control unit 95 operates the first heating unit 30A to heat the first raw material container 21A to a predetermined temperature (step S1).
[0071] With the first source material container 21A heated to a predetermined temperature, the supply operation control unit 95 supplies (circulates) the carrier gas from the carrier gas supply mechanism 40 to the first upstream path 51A connected to the first source material container 21A (step S2). At this time, the supply operation control unit 95 adjusts the flow rate of the carrier gas flowing toward the first source material container 21A using the mass flow controllers 54 and 56.
[0072] Furthermore, as the carrier gas flows, the pressure acquiring unit 96 detects the pressure in the first upstream path 51A using the first upstream pressure gauge 70A, and detects the pressure in the first downstream path 52A using the first downstream pressure gauge 71A (step S3). Then, in the process of starting the supply of the source gas, the pressure acquiring unit 96 continuously acquires pressure detection values from the first upstream pressure gauge 70A and the first downstream pressure gauge 71A, and stores them in the memory 92.
[0073] The supply operation control unit 95 opens the first bypass valve 63A to allow the carrier gas to flow through the first bypass path 53A without passing through the first raw material container 21A (step S4: see also FIG. 4(b)). As a result, as shown in FIGS. 5(a) and 6(a), the pressure detection values of the first upstream pressure gauge 70A and the first downstream pressure gauge 71A decrease after the start time t0.
[0074] Furthermore, the supply operation control unit 95 opens the first downstream valve 62A to allow the gas containing the source gas generated from the source material M in the first source material container 21A to flow through the first downstream path 52A (step S5: also see FIG. 4(c)). As the source gas flows out of the first source material container 21A, the pressure detection values of the first upstream pressure gauge 70A and the first downstream pressure gauge 71A continue to decrease even after time t1 shown in FIGS. 5(a) and 6(a).
[0075] The remaining amount estimating unit 97 estimates the remaining amount of raw material M in the first source container 21A based on the detected pressure value that decreases when the first downstream valve 62A is opened (step S6). At this time, the remaining amount estimating unit 97 obtains information on the opening and closing timing of each on-off valve 60 from the supply operation control unit 95 and extracts two detected pressure values from the detected pressure values of the first upstream pressure gauge 70A stored in the memory 92. For example, the remaining amount estimating unit 97 extracts the detected pressure value of the first upstream pressure gauge 70A at the start time t0 and the detected pressure value of the first upstream pressure gauge 70A at the start time t2, and calculates the pressure difference between the detected pressure values of the first upstream pressure gauge 70A at the start of the supply of the source gas. The remaining amount estimating unit 97 also calculates the remaining amount of raw material M in the first source container 21A based on the calculated pressure difference and map information IA. Alternatively, the remaining amount estimation unit 97 extracts the pressure detection value of the first downstream pressure gauge 71A at the start time t0 and the pressure detection value of the first downstream pressure gauge 71A at the time t2, and calculates the pressure difference between the pressure detection values of the first downstream pressure gauge 71A at the start of the supply of the source gas. Furthermore, the remaining amount estimation unit 97 calculates the remaining amount of the source material M in the first source container 21A based on the calculated pressure difference and the map information IB. When the remaining amount based on the pressure detection value of the first upstream pressure gauge 70A and the remaining amount based on the pressure detection value of the first downstream pressure gauge 71A are calculated, the remaining amount estimation unit 97 calculates the remaining amount of the source material M in the first source container 21A appropriately.
[0076] Thereafter, the remaining amount estimating unit 97 notifies the user of the calculated remaining amount of raw material M in the first source container 21A via the user interface 18 (step S7). This allows the user of the substrate processing system 1 to recognize the remaining amount of raw material M in the first source container 21A and determine the timing for replacing the first source container 21A. Note that the remaining amount estimating unit 97 may be configured to notify the user of the timing for replacing the first source container 21A based on the calculated remaining amount of raw material M in the first source container 21A.
[0077] The remaining amount estimating unit 97 can estimate the remaining amount of raw material M in the second raw material container 21B in the same manner as the remaining amount of raw material M in the first raw material container 21A. That is, the remaining amount estimating unit 97 can estimate the remaining amount of raw material M in the second raw material container 21B based on the pressure detection value of the second upstream pressure gauge 70B or the pressure detection value of the second downstream pressure gauge 71B.
[0078] As described above, the raw material supply device 20 and the substrate processing system 1 estimate the remaining amount of raw material M in the raw material container 21 using the pressure gauge 70 around the raw material container 21. This makes it possible to directly monitor the remaining amount of raw material M in the raw material container 21, the interior of which is invisible, using an index that correlates with the remaining amount of raw material M with high accuracy, rather than the conventional indirect estimation using the usage time or the number of processes.
[0079] The raw material supply device 20, the substrate processing system 1, and the remaining amount estimation method according to the present embodiment are not limited to the above embodiment, and various modifications are possible. For example, in the remaining amount estimation method according to the above embodiment, the pressure difference from the start time t0 to time t2 is calculated as an index for estimating the remaining amount of raw material M. However, the remaining amount estimation method may use the pressure difference from the start time t0 to time t3, or the pressure difference from time t1 to time t2, or the pressure difference from time t1 to time t3.
[0080] FIG. 8(a) is a schematic diagram showing the raw material container 21 and heating unit 30 of a modified raw material supply apparatus 20, and FIG. 8(b) is a timing chart illustrating an example of an operation pattern of the heating unit 30. As shown in FIG. 8(a), the raw material supply apparatus 20 may have a configuration in which the heating unit 30 is divided into multiple sections corresponding to the multiple trays 22 arranged vertically in the raw material containers 21 (first raw material container 21A, second raw material container 21B). For example, the heating unit 30 includes an upper heater 32, a center heater 33, and a lower heater 34. Each heater (the upper heater 32, the center heater 33, and the lower heater 34) can effectively heat the raw material M in the trays 22 arranged at the same vertical height.
[0081] The supply control unit 90 (supply operation control unit 95) of the raw material supply device 20 individually controls each of the upper heater 32, the central heater 33, and the lower heater 34. As an example, as shown in FIG. 8(b), the supply operation control unit 95 operates the upper heater 32 at a predetermined set temperature, then operates the central heater 33 at a predetermined set temperature, and further operates the lower heater 34 at a predetermined set temperature. Of course, any two or all three of the upper heater 32, the central heater 33, and the lower heater 34 may operate (heat) simultaneously.
[0082] Furthermore, the remaining amount estimation unit 97 of the supply control unit 90 can estimate the variation in the remaining amount of raw material M on each tray 22 by observing a decrease in the detected pressure value when the supply of raw material gas from the raw material container 21 starts with the upper heater 32, the central heater 33, and the lower heater 34 operating individually. That is, the raw material container 21 may have a variation in the consumption amount of raw material M for each tray 22 in the vertical direction due to individual differences, piping layout, etc. Due to this variation, for example, when the remaining amount of raw material M on one tray 22 approaches zero, the vaporization rate of raw material M decreases even if a large amount of raw material M remains on the other trays 22, and the uniformity of the process in the supply of raw material gas cannot be maintained.
[0083] For example, the remaining amount estimation unit 97 estimates the remaining amount of raw material M for each tray 22 in the vertical direction based on a decrease in the detected pressure value when only the upper heater 32 is heated, a decrease in the detected pressure value when only the central heater 33 is heated, and a decrease in the detected pressure value when only the lower heater 34 is heated. The estimated remaining amount of raw material M for each tray 22 may be a relative value between the trays 22 or an absolute value. Alternatively, the remaining amount estimation unit 97 may estimate the remaining amount of raw material M for each tray 22 based on a decrease in the detected pressure value when the upper heater 32 and the central heater 33 are heated, when the upper heater 32 and the lower heater 34 are heated, and when the central heater 33 and the lower heater 34 are heated.
[0084] Then, the supply control unit 90 feeds back the variation in the remaining amount of raw material M estimated by the remaining amount estimation unit 97 to the heating amount of the heating unit 30 during subsequent substrate processing. As a result, the heating unit 30 individually adjusts the heating amount of each of the upper heater 32, the central heater 33, and the lower heater 34. As a result, the raw material supply device 20 can reduce the variation in the remaining amount of raw material M and maintain the raw material gas supply performance until the remaining amount of raw material M in all trays 22 in the raw material container 21 approaches zero.
[0085] FIG. 9 is a flowchart showing an example of a process flow of a remaining amount estimation method according to a modified example. As shown in FIG. 9, in the remaining amount estimation method for estimating the variation of raw material M, the supply operation control unit 95 first heats the first raw material container 21A using only the upper heater 32 (step S11). The remaining amount estimation unit 97 then estimates the remaining amount of raw material M in the first raw material container 21A based on the pressure detection value of the first upstream pressure gauge 70A or the pressure detection value of the first downstream pressure gauge 71A (step S12). The remaining amount of raw material M in the first raw material container 21A can be estimated using the same process as in the process flow shown in FIG. 7. The remaining amount of raw material M in the first raw material container 21A calculated in step S12 mainly reflects the amount of raw material gas flowing out from the raw material M in the upper tray 22. However, raw material gas also flows out from the raw material M in the other trays 22.
[0086] Therefore, the next time the source gas is supplied to the substrate processing apparatus 10, the supply operation control unit 95 heats the first source container 21A only by the center heater 33 (step S13). The remaining amount estimation unit 97 estimates the remaining amount of source material M in the first source container 21A based on the pressure detection value of the first upstream pressure gauge 70A or the pressure detection value of the first downstream pressure gauge 71A at this time (step S14). The remaining amount of source material M in the first source container 21A calculated in step S14 mainly reflects the outflow amount of source gas generated from the source material M in the central tray 22. However, source gas also flows out from the source material M in the other trays 22.
[0087] Furthermore, when supplying the source gas to the substrate processing apparatus 10, the supply operation control unit 95 heats the first source container 21A only by the lower heater 34 (step S15). The remaining amount estimation unit 97 estimates the remaining amount of the source material M in the first source container 21A based on the pressure detection value of the first upstream pressure gauge 70A or the pressure detection value of the first downstream pressure gauge 71A at this time (step S16). The remaining amount of the source material M in the first source container 21A calculated in step S16 mainly reflects the outflow amount of the source gas generated from the source material M in the lower tray 22. However, source gas also flows out from the source material M in the other trays 22.
[0088] The remaining amount estimating unit 97 then calculates the variation in the remaining amount of raw material M in the first raw material container 21A using the remaining amount when heated by the upper heater 32, the remaining amount when heated by the center heater 33, and the remaining amount when heated by the lower heater 34 (step S17). For example, the remaining amount estimating unit 97 defines the remaining amount when heated by the upper heater 32 as X, the remaining amount when heated by the center heater 33 as Y, and the remaining amount when heated by the lower heater 34 as Z, and also uses parameters such as the heating temperature of each heater and its influence on the raw material M, which are stored in advance. The remaining amount estimating unit 97 then estimates the variation in the remaining amount of raw material M using an appropriate calculation formula (for example, a simultaneous equation).
[0089] Then, based on the estimation result of the variation in the remaining amount of raw material M, the supply control unit 90 controls the operation of the upper heater 32, the center heater 33, and the lower heater 34 when supplying the raw material gas from the first raw material container 21A to the processing container 11 (step S18). For example, the supply operation control unit 95 uses the estimation result to individually adjust the heating timing, heating period, temperature, etc. of each heater. This allows the raw material supply device 20 to approximately equalize the remaining amount of raw material M in the first raw material container 21A. It goes without saying that the raw material supply device 20 can also perform the same process for the second raw material container 21B.
[0090] The technical ideas and effects of the present disclosure explained in the above embodiments will be described below.
[0091] a downstream path (first downstream path 52A) connected to the raw material container 21 and allowing a gas containing a raw material gas generated from the raw material M to flow; a bypass path (first bypass path 53A) connecting the upstream path and the downstream path without passing through the raw material container 21 and allowing a carrier gas to flow from the upstream path to the downstream path; a downstream valve (first downstream valve 62A) opening and closing a flow path of the downstream path; a pressure gauge 70 provided in at least one of the upstream path and the downstream path and detecting a pressure in the upstream path or the downstream path; and a remaining amount estimation unit 97 configured to acquire a detected pressure value from the pressure gauge 70 and estimate a remaining amount of the raw material M in the raw material container 21 based on the detected pressure value that decreases when the downstream valve is opened at the time when the raw material gas starts to flow from the raw material container 21 to the downstream path.
[0092] The raw material supply device 20 described above uses the pressure detection value of the pressure gauge 70 when starting the flow of the raw material gas to more directly grasp the state of the raw material M in the raw material container 21 and accurately estimate the remaining amount of raw material M in the raw material container 21. As a result, the raw material supply device 20 uses the raw material M in the raw material container 21 nearly to its limit, reducing the number of raw material container 21 replacements and waste raw material, thereby reducing running costs. Furthermore, since the pressure gauge 70, which is generally applied near the raw material container 21, can be used, the raw material supply device 20 does not need to install a remaining amount sensor or concentration sensor in the raw material container 21, thereby reducing costs. In addition, the raw material supply device 20 can stabilize the pressure in the upstream path (first upstream path 51A) and the downstream path by flowing carrier gas through the downstream path (first downstream path 52A) via the bypass path (first bypass path 53A). In this state, monitoring the pressure detection value when the downstream valve (first downstream valve 62A) is opened makes it possible to accurately grasp pressure drops.
[0093] Furthermore, the remaining amount estimation unit 97 calculates the amount of decrease in the pressure detection value, and estimates that the larger the amount of decrease, the smaller the amount of raw material M remaining in the raw material container 21. This allows the raw material supply device 20 to recognize that the remaining amount of raw material M is small when the amount of decrease in the pressure detection value becomes large.
[0094] Furthermore, map information IA and IB, which associate the amount of decrease in the detected pressure value with the remaining amount of raw material M in the raw material container 21, is stored in the memory unit 97a, and the remaining amount estimation unit 97 refers to the memory unit 97a based on the calculated amount of decrease in the detected pressure value, and extracts the remaining amount of raw material M in the raw material container 21 from the map information IA and IB. This allows the remaining amount estimation unit to easily obtain the remaining amount of raw material M in the raw material container 21 according to the amount of decrease in the detected pressure value.
[0095] The raw material supply device 20 also includes a bypass-side valve (first bypass-side valve 63A) that opens and closes the flow path of the bypass path (first bypass path 53A). The remaining amount estimation unit 97 estimates the remaining amount of raw material M in the raw material container 21 based on the pressure detection value when the bypass-side valve and the downstream valve (first downstream valve 62A) are opened at the start of flow of raw material gas from the raw material container 21 to the downstream path (first downstream path 52A). By opening the bypass-side valve to flow carrier gas through the bypass path, the raw material supply device 20 can suppress a sudden increase in pressure in the raw material container 21 due to the carrier gas flowing into the raw material container 21. The remaining amount estimation unit can stably estimate the remaining amount of raw material M in the raw material container 21 based on the decrease in the pressure detection value when both the bypass-side valve and the downstream valve are opened.
[0096] The raw material supply device 20 also has an upstream valve (first upstream valve 61A) that opens and closes the flow path of the upstream path (first upstream path 51A), and the remaining amount estimation unit 97 opens the bypass valve (first bypass valve 63A) and the downstream valve (first downstream valve 62A) when the raw material gas starts to flow from the raw material container 21 to the downstream path (first downstream path 52A), and estimates the remaining amount of raw material M in the raw material container 21 based on the pressure detection value when the upstream valve is opened. This allows the raw material supply device 20 to smoothly flow the carrier gas from the upstream path to the raw material container 21, and also allows the remaining amount of raw material M in the raw material container 21 to be appropriately estimated using the decrease in the pressure detection value at this time.
[0097] Furthermore, a pressure gauge 70 is provided in each of the upstream path (first upstream path 51A) and the downstream path (first downstream path 52A), and the remaining amount estimation unit 97 estimates the remaining amount of raw material M in the raw material container 21 using both the pressure detection value of the pressure gauge 70 in the upstream path and the pressure detection value of the pressure gauge 70 in the downstream path. This allows the raw material supplying device 20 to estimate the remaining amount of raw material M in the raw material container 21 with even greater accuracy.
[0098] The raw material supply device 20 also has a plurality of heating units 30 (upper heater 32, central heater 33, lower heater 34) for heating the raw material container 21, and the remaining amount estimation unit 97 estimates the variation in the remaining amount of the raw material M contained in the raw material container 21 by selectively heating some of the plurality of heating units 30. This enables the raw material supply device 20 to estimate the remaining amount of the raw material M for each region corresponding to the plurality of heating units 30, and by controlling the plurality of heating units 30 in accordance with the variation in the remaining amount of each raw material M, the variation in the remaining amount of each raw material M can be reduced.
[0099] A second aspect of the present disclosure is a substrate processing system 1 that supplies a source gas to a processing vessel 11 that processes a substrate, the system including: a supply path 14 connected to the processing vessel 11; a source vessel 21 that accommodates a solid or liquid source material M; an upstream path (first upstream path 51A) connected to the source vessel 21 and through which a carrier gas can flow; a downstream path (first downstream path 52A) that connects the source vessel 21 and the supply path 14 and through which a gas containing a source gas generated from the source material M can flow; and a downstream path (first downstream path 52A) that connects the upstream path and the downstream path without passing through the source vessel 21, and The system includes a bypass path (first bypass path 53A) for circulating a carrier gas, a downstream valve (first downstream valve 62A) for opening and closing the flow path of the downstream path, a pressure gauge 70 provided in at least one of the upstream path and the downstream path for detecting the pressure in the upstream path or the downstream path, and a remaining amount estimation unit 97 configured to acquire a pressure detection value from the pressure gauge 70 and estimate the remaining amount of raw material M in the raw material container 21 based on the detected pressure value that decreases when the downstream valve is opened at the start of flow of raw material gas from the raw material container 21 to the downstream path.
[0100] a downstream path (first downstream path 52A) connected to the raw material container 21 via a bypass path (first bypass path 53A) connecting the upstream path and the downstream path (first downstream path 52A) connected to the raw material container 21 without passing through the raw material container 21; a downstream valve (first downstream valve 62A) provided in the downstream path to allow a gas containing a raw material gas generated from the raw material M to pass through the downstream path; a pressure gauge 70 provided in at least one of the upstream path and the downstream path to detect a pressure in the upstream path or the downstream path; and a pressure detection value from the pressure gauge 70 to estimate the remaining amount of the raw material M in the raw material container 21 based on the detected pressure value, which decreases when the downstream valve is opened at the time when the raw material gas starts to pass from the raw material container 21 to the downstream path.
[0101] In the second and third embodiments, the remaining amount of the raw material M in the raw material container 21 can also be estimated with high accuracy.
[0102] The raw material supply device 20, the substrate processing system 1, and the remaining amount estimation method according to the presently disclosed embodiments are illustrative in all respects and are not limiting. The embodiments can be modified and improved in various ways without departing from the spirit and scope of the appended claims. The matters described in the above embodiments can be configured differently and can be combined within a consistent range.
[0103] The substrate processing system 1 of the present disclosure can be applied to any type of apparatus, including atomic layer deposition (ALD) apparatus, capacitively coupled plasma (CCP), inductively coupled plasma (ICP), radial line slot antenna (RLSA), electron cyclotron resonance plasma (ECR), and helicon wave plasma (HWP). [Explanation of symbols]
[0104] 1. Substrate Processing System 20 Raw material supply device 21 Raw material container 51A First upstream route 52A First Downstream Route 53A First Bypass Route 62A First downstream valve 70 Pressure Gauge 90 Supply control section M Raw material
Claims
1. a raw material container containing a solid or liquid raw material; an upstream path connected to the source container and through which a carrier gas can flow; a downstream path connected to the source container and capable of passing a gas containing a source gas generated from the source material; a bypass path that connects the upstream path and the downstream path without passing through the raw material container and allows the carrier gas to flow from the upstream path to the downstream path; a downstream valve that opens and closes the flow path of the downstream path; a pressure gauge provided in each of the upstream path and the downstream path, for detecting a pressure in the upstream path or the downstream path, respectively; a remaining amount estimating unit configured to acquire a pressure detection value of the pressure gauge of the upstream path and a pressure detection value of the pressure gauge of the downstream path, and estimate a remaining amount of the raw material in the raw material container based on the pressure detection value that decreases when the downstream valve is opened at the time when the raw material gas starts to flow from the raw material container to the downstream path, the remaining amount estimating unit estimates the remaining amount of the raw material in the raw material container by using both the pressure detection value of the pressure gauge in the upstream path and the pressure detection value of the pressure gauge in the downstream path. Raw material supply equipment.
2. the remaining amount estimation unit calculates a decrease amount of the pressure detection value, and estimates that the larger the decrease amount is, the smaller the remaining amount of the raw material in the raw material container is. The raw material supply device according to claim 1 .
3. information correlating the amount of decrease in the pressure detection value with the remaining amount of the raw material in the raw material container is stored in a storage unit; the remaining amount estimation unit refers to the storage unit based on the calculated amount of decrease in the pressure detection value, and extracts the remaining amount of the raw material in the raw material container from the information. The raw material supply device according to claim 2.
4. a bypass-side valve that opens and closes the flow path of the bypass path; the remaining amount estimating unit estimates the remaining amount of the raw material in the raw material container based on the pressure detection value when the bypass valve and the downstream valve are opened at the start of flow of the raw material gas from the raw material container to the downstream path. The raw material supply device according to any one of claims 1 to 3.
5. an upstream valve that opens and closes the flow path of the upstream path; the remaining amount estimating unit opens the bypass valve, opens the downstream valve, and estimates the remaining amount of the raw material in the raw material container based on the pressure detection value when the upstream valve is also opened at the start of flow of the raw material gas from the raw material container to the downstream path. The raw material supply device according to claim 4.
6. a plurality of heating units for heating the raw material container; the remaining amount estimation unit estimates the remaining amounts of the raw materials contained in the raw material container when some of the heating units are selectively heated. The raw material supply device according to any one of claims 1 to 5.
7. A substrate processing system for supplying a source gas to a processing chamber for processing a substrate, a supply path connected to the processing vessel; a raw material container containing a solid or liquid raw material; an upstream path connected to the source container and through which a carrier gas can flow; a downstream path that connects the source material container and the supply path and through which a gas containing a source gas generated from the source material can flow; a bypass path that connects the upstream path and the downstream path without passing through the raw material container and allows the carrier gas to flow from the upstream path to the downstream path; a downstream valve that opens and closes the flow path of the downstream path; a pressure gauge provided in each of the upstream path and the downstream path, for detecting a pressure in the upstream path or the downstream path, respectively; a remaining amount estimating unit configured to acquire a pressure detection value of the pressure gauge of the upstream path and a pressure detection value of the pressure gauge of the downstream path, and estimate a remaining amount of the raw material in the raw material container based on the pressure detection value that decreases when the downstream valve is opened at the time when the raw material gas starts to flow from the raw material container to the downstream path, the remaining amount estimating unit estimates the remaining amount of the raw material in the raw material container by using both the pressure detection value of the pressure gauge in the upstream path and the pressure detection value of the pressure gauge in the downstream path. Substrate processing system.
8. A remaining amount estimation method for estimating the remaining amount of a solid or liquid raw material contained in a raw material container, a step of flowing a carrier gas through an upstream path connected to the raw material container; a step of circulating the carrier gas from the upstream path to the downstream path via a bypass path that connects the upstream path and the downstream path connected to the raw material container, without passing through the raw material container; a step of opening a downstream valve provided in the downstream path to allow a gas containing a source gas generated from the source material to flow through the downstream path; detecting a pressure in the upstream path or the downstream path by a pressure gauge provided in both the upstream path and the downstream path, respectively; acquiring a pressure detection value of the pressure gauge of the upstream path and a pressure detection value of the pressure gauge of the downstream path, and estimating a remaining amount of the raw material in the raw material container based on the pressure detection value that decreases when the downstream valve is opened at the start of flow of the raw material gas from the raw material container to the downstream path, In the step of estimating the remaining amount of the raw material, the remaining amount of the raw material in the raw material container is estimated using both the pressure detection value of the pressure gauge in the upstream path and the pressure detection value of the pressure gauge in the downstream path. Remaining amount estimation method.
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