Patent Application
20230302482
The present invention relates to a film-forming atomizer, a film-forming apparatus, and a film-forming method.
As a method that can form an epitaxial film, etc. at a low temperature and the atmospheric pressure, known is a film-forming technique using liquid fine particles, such as a mist CVD method. Patent Document 1 discloses a method in which a container containing a raw material solution is subjected to an ultrasonic wave vibrator to atomize the raw material solution into mist, and the obtained raw material mist is supplied with carrier gas onto a substrate in a reaction chamber in which film-forming is performed.
The ultrasonic wave is applied to the raw material liquid commonly through an intermediate liquid, such as water, for availability of varied materials including a corrosive raw material liquid. However, continuously applying the ultrasonic wave generates bubbles from the intermediate liquid to cause a problem of inhibiting the ultrasonic wave propagation to the raw material liquid to decrease the generation amount of the mist. Whereas, Patent Document 2 discloses a method in which an angle of a bottom face of the raw material container is provided relative to a liquid level of the intermediate liquid to avoid bubble adhesion onto the bottom face of the raw material container.
In the structure in Patent Document 2, however, the raw material liquid has ununiform depth in the raw material container, and thereby the raw material liquid cannot be sufficiently atomized when, in particular, a plurality of ultrasonic wave generators is employed. Moreover, there is a problem that the atomizer structure becomes complex and expensive.
The present invention has been made to solve the above-described problem. An object of the present invention is to provide: a film-forming atomizer that can continuously atomize the raw material liquid with high efficiency; a film-forming apparatus including such an atomizer; and a film-forming method that can stably form a film with high productivity.
To achieve the above object, the present invention provides a film-forming atomizer atomizing a raw material liquid with ultrasonic wave to generate a raw material mist, the atomizer comprising:
Such an atomizer can prevent retention of gas in the intermediate liquid on the bottom of the raw material container and others as bubbles, and can suppress prevention of the ultrasonic wave propagation to the raw material liquid due to the bubbles, and thereby the ultrasonic can be continuously propagated to the raw material liquid with high efficiency. As a result, the inventive atomizer can continuously atomize the raw material liquid with high efficiency. In addition, the inventive atomizer, which can continuously atomize the raw material liquid, can atomize a raw material liquid having a high density. The film-forming apparatus including such an atomizer can form a stable film with high productivity.
In the film-forming atomizer, an injection port for injecting the intermediate liquid from the circulation mechanism to the propagation vessel is preferably provided at a position lower than a bottom face of the raw material container.
Such an atomizer can efficiently remove gas in the intermediate liquid, and consequently the atomizer can continuously atomize the raw material liquid with higher efficiency.
In the film-forming atomizer, a draining port for draining the intermediate liquid from the propagation vessel to the circulation mechanism is preferably provided at a position higher than a bottom face of the raw material container.
Such an atomizer can efficiently remove gas in the intermediate liquid, and consequently the atomizer can continuously atomize the raw material liquid with higher efficiency.
The raw material container preferably comprises a horizontal bottom face.
Such an atomizer can uniformize the depth of the raw material liquid in the raw material container, and thereby the atomizer can more sufficiently atomize the raw material liquid. As a result, the atomizer can continuously the raw material liquid with higher efficiency. In addition, such a shape can simplify the apparatus structure to contribute to cost reduction.
The degassing mechanism may be provided on the propagation vessel.
In this case, for example, the degassing mechanism may spatially connect an internal part and an external part of a space surrounded by the propagation vessel and the support mechanism to support the raw material container.
Alternatively, the degassing mechanism may be provided on the circulation mechanism.
As above, the degassing mechanism may be provided at any position where the intermediate liquid can be present.
The present invention also provides a film-forming apparatus configured to supply a raw material mist to a film-forming device and to form a thin film on a base substrate provided on the film-forming device, the apparatus comprising:
Such a film-forming apparatus, which includes the inventive film-forming atomizer, can stably and continuously form a film, and can be an apparatus with high productivity.
The present invention also provides a film-forming method for supplying a raw material mist to a film-forming device and forming a thin film on a base substrate provided on the film-forming device, the method comprising:
Such a film-forming method, which involves the inventive film-forming atomizer, can stably and continuously perform film-forming on a large-size substrate, the film-forming on the large-size substrate requiring a longer time, and can perform a stable film-forming with high productivity.
As described above, the inventive film-forming atomizer can continuously propagate the ultrasonic wave to the raw material liquid with high efficiency, and can be an atomizer that can stably atomize the raw material liquid. That is, the inventive film-forming atomizer can continuously atomize the raw material liquid with high efficiency.
The inventive film-forming apparatus can stably form a film with high productivity.
The inventive film-forming method can stably form a film with high productivity.
The present invention relates to: a film-forming atomizer used for forming a film, the atomizer atomizing a raw material liquid with ultrasonic wave from an ultrasonic wave generator, such as an ultrasonic wave vibrator; and a film-forming apparatus and a film-forming method each using this film-forming atomizer.
As described above, there have been demands for the developments of a film-forming atomizer that can continuously atomize a raw material liquid with high efficiency.
The present inventors have earnestly studied the above problem and consequently found that, in a film-forming atomizer atomizing a raw material liquid with ultrasonic wave to generate a raw material mist, the film-forming atomizer including a circulation mechanism to circulate an intermediate liquid in a propagation vessel and a degassing mechanism to discharge gas in the intermediate liquid out of the film-forming atomizer, this intermediate liquid can be transferred so that the gas in the intermediate liquid moves toward the degassing mechanism, and this configuration can efficiently discharge the gas in the intermediate liquid out of the film-forming atomizer. This finding has led to the completion of the present invention.
Specifically, the present invention is a film-forming atomizer atomizing a raw material liquid with ultrasonic wave to generate a raw material mist, the atomizer comprising:
In addition, the present invention is a film-forming apparatus configured to supply a raw material mist to a film-forming device and to form a thin film on a base substrate provided on the film-forming device, the apparatus comprising:
In addition, the present invention is a film-forming method for supplying a raw material mist to a film-forming device and forming a thin film on a base substrate provided on the film-forming device, the method comprising:
Hereinafter, the present invention will be described in detail with reference to the drawings, but the present invention is not limited thereto.
[Film-Forming Atomizer]
The inventive film-forming atomizer is a film-forming atomizer atomizing a raw material liquid with ultrasonic wave to generate a raw material mist, the atomizer including:
The film-forming atomizer including the propagation vessel containing the intermediate liquid as a medium for propagating ultrasonic wave to the raw material liquid, the atomizer atomizing (micronizing) the raw material liquid with the ultrasonic wave to generate a raw material mist (raw material fine particles), has the problem that, as described above, continuously applying the ultrasonic wave generates bubbles of gas contained in the intermediate liquid, and these bubbles retain between the intermediate liquid and the raw material container to inhibit the ultrasonic wave propagation to the raw material liquid.
The inventive film-forming atomizer includes: the circulation mechanism to circulate the intermediate liquid; and the degassing mechanism to discharge gas in the intermediate liquid out of the film-forming atomizer, and thereby, as described above, the inventive film-forming atomizer can transfer this intermediate liquid so that the gas in the intermediate liquid moves toward the degassing mechanism. According to this configuration, the inventive film-forming atomizer can efficiently discharge the gas in the intermediate liquid out of the film-forming atomizer. As a result, the inventive film-forming atomizer can continuously atomize the raw material liquid with high efficiency. In addition, the inventive atomizer, which can continuously atomize the raw material liquid, can atomize a raw material liquid having a high density.
In the film-forming atomizer, an injection port for injecting the intermediate liquid from the circulation mechanism to the propagation vessel is preferably provided at a position lower than a bottom face of the raw material container.
Furthermore, in the film-forming atomizer, a draining port for draining the intermediate liquid from the propagation vessel to the circulation mechanism is preferably provided at a position higher than a bottom face of the raw material container.
An atomizer according to any one of the preferred aspects can further enhance a transfer of the intermediate liquid in which gas in the intermediate liquid moves toward the degassing mechanism, and thereby the gas in the intermediate liquid can be removed more efficiently. As a result, the atomizer can continuously atomize the raw material liquid with higher efficiency.
The raw material container preferably includes a horizontal bottom face.
Such an atomizer can uniformize a depth of the raw material liquid in the raw material container, and thereby the atomizer can sufficiently atomize the raw material liquid. As a result, the atomizer can continuously atomize the raw material liquid with higher efficiency. In addition, such an atomizer can simplify the apparatus shape to contribute to reduction in an apparatus cost.
The degassing mechanism is to discharge the gas in the intermediate liquid out of the film-forming atomizer, and therefore may be provided at any position where the intermediate liquid can be present.
For example, the degassing mechanism may be provided on the propagation vessel, or may be provided on the circulation mechanism.
The inventive film-forming atomizer can include a component other than the raw material container, the propagation vessel, the support mechanism, the circulation mechanism, the ultrasonic wave generator, and the degassing mechanism. For specific examples thereof, see the following description.
Hereinafter, specific examples of the inventive film-forming atomizer will be described with reference to
The film-forming atomizer 100 further includes: a tubular member 112 spatially connecting an internal part and an external part of the raw material container 111, and provided so that a lower end thereof is not contacted with a liquid level of the raw material liquid 114 in the raw material container 111; and a pipe 132 fluid-connecting the propagation vessel 121 and the circulation mechanism 131.
The circulation mechanism 131 is configured to circulate the intermediate liquid 126 between the circulation mechanism 131 and the propagation vessel 121 through the pipe 132 in the arrow direction. The circulation mechanism 131 may further have a temperature controlling function for the intermediate liquid 126.
The raw material container 111 preferably includes a horizontal bottom face, as illustrated in
On the raw material container 111, a carrier gas inlet port 113 for introducing a carrier gas 141 is provided. Although shapes of the raw material container 111 and the tubular member 112 are not particularly limited, those having cylindrical shapes can smoothly transfer a mixed gas 142 which is formed by mixing the carrier gas 141 and a raw material mist (not illustrated) atomized by means of the ultrasonic wave with each other. The carrier gas inlet port 113 is preferably provided above the lower end of the tubular member 112 inside the raw material container 111. By such a configuration, the carrier gas 141 and the raw material mist can be sufficiently mixed with each other.
Although not illustrated, the atomizer 100 may further includes a mechanism to refill the raw material liquid 114 depending on its consumption.
The propagation vessel 121 is a member to contain the intermediate 126 for propagating the ultrasonic wave irradiated from the ultrasonic wave generator 122 to the raw material liquid 114.
The ultrasonic wave-irradiation surface of the ultrasonic wave generator 122 is flat. The irradiation direction may be fixed by inclining this irradiation surface, or may be inclined by appropriately regulating the angle. A plurality of the ultrasonic wave generators 112 may be provided depending on a desired mist density, size of the raw material container 111, etc. A frequency of the ultrasonic wave oscillated from the ultrasonic wave generator 122 is not particularly limited as long as the generated mist has desired particle diameter and particle size, and favorably used frequency is 1.5 MHz to 4.0 MHz, for example. This configuration atomizes the raw material liquid 114 into a mist (performs atomization) of micron-sized droplets (raw material mist), suitable for film formation.
The raw material liquid 114 is not particularly limited as long as it is atomized by the ultrasonic wave, and can be appropriately selected depending on a thin film to be formed.
The intermediate liquid 126 is not particularly limited as long as it does not inhibit the ultrasonic wave propagation. Water, alcohols, and oils may be used as the intermediate liquid 126, but in particular, water is preferably used in the present invention. Although not illustrated, the propagation vessel 121 may further include a means for detecting and controlling a liquid level and temperature of the intermediate liquid 126.
As illustrated in
The degassing mechanism 127 is provided above the draining port 125 of the propagation vessel 121. The degassing mechanism 127 spatially connects an internal part and an external part of a space surrounded by the propagation vessel 121 and the support mechanism 123 to support the raw material container 111. The bubbles moved with the flow of the intermediate liquid 126 rises in the intermediate liquid 126 to be discharged through the degassing mechanism 127 out of the film-forming atomizer 100. Since the bubbles are released through the degassing mechanism 127 out of the film-forming atomizer 100 as above, avoided is inhibition of the ultrasonic wave propagation due to bubbles floats in a long time in the intermediate liquid 126. A flow rate of the intermediate liquid 126 in this time is not particularly limited as long as it is a rate to transfer the bubble generated in the intermediate liquid 126, and typically favorably 1 L/min or more to 20 L/min.
In
For example, as illustrated in
Alternatively, as illustrated in
In
A method for supporting the raw material container preferably does not inhibit the flow of the intermediate liquid in the bottom of the raw material container. For example, the support mechanism may have a structure of a plurality of pillars stood in the propagation vessel to mount the raw material container thereon.
Members constituting the film-forming atomizer are not particularly limited as long as they are material and structure having: chemical stability against the raw material liquid and the intermediate liquid; and sufficient mechanical strength. For example, a metal, a plastic material, glass, a material in which a metal surface is coated with a plastic material, etc. can be used.
[Film-Forming Apparatus]
The inventive film-forming apparatus is configured to supply a raw material mist to a film-forming device and to form a thin film on a base substrate provided on the film-forming device, the apparatus comprising:
The inventive film-forming apparatus, which includes the inventive film-forming atomizer, can stably and continuously form a film, and can be an apparatus with high productivity.
Hereinafter, specific examples of the inventive film-forming apparatus will be described with reference to
A film-forming apparatus 400 illustrated in
The film-forming atomizer 100 is the atomizer 100 of the example of the inventive film-forming atomizer described with reference to
As described above, the film-forming atomizer 100 is configured to atomize the raw material liquid 114 with the ultrasonic wave to generate the raw material mist 422.
The supplying mechanism 410 includes a carrier gas supplier 411 and pipes 413 and 424. The carrier gas supplier 411 is connected to the film-forming atomizer 100 via the pipe 413. The carrier gas supplier 411 is configured to supply the carrier gas 141 to the film-forming atomizer 100 via the pipe 413. The film-forming atomizer 100 is connected to the film-forming device 430 via the pipe 424. The mixed gas 142 of the carrier gas 141 and the raw material mist 422 is supplied to the film-forming device 430 via the pipe 424. That is, the supplying mechanism 410 is configured to supply the raw material mist 422 generated by atomization with the film-forming atomizer 100 to the film-forming device 430 with the carrier gas 141.
The carrier gas supplier 411 may be an air compressor, gas cylinders, or a nitrogen gas separator, and may include a mechanism to regulate a supplying rate of the gas. The pipes 413 and 424 are not particularly limited as long as they have sufficient stability against the raw material liquid 114 and a temperature near the film-forming device 430. For the pipes 413 and 424, a quartz pipe and a pipe made of a common resin, such as polyethylene, polypropylene, vinyl chloride, a silicone resin, a urethane resin, and a fluororesin can be widely used. Although not illustrated, another pipe may be connected from the carrier gas supplier 411 to the pipe 424 without involving the film-forming atomizer 100 to enable to supply a dilution gas to the mixed gas 142.
A plurality of the film-forming atomizers 100 may be composed depending on a material to be formed into a film, etc. In this case, the mixed gases 142 supplied from the plurality of the atomizers 100 to the film-forming device 430 may be each independently supplied to the film-forming device 430, may be mixed in the pipe 424, or may be mixed in a separately provided container for mixing (not illustrated).
The film-forming device 430 may include: a film-forming chamber 431; a susceptor 432 provided in this film-forming chamber 431 to hold a base substrate 434 on which a film is formed; and a heating means 433 to heat the base substrate 434.
A structure, etc. of the film-forming chamber 431 are not particularly limited. For example, metals such as aluminum and stainless steel may be used, or quartz or silicon carbide may be used when a film is formed at higher temperature.
The heating means 433 may be selected depending on a material and structure of the base substrate 434, the susceptor 432, and the film-forming chamber 431, and a resistance heater and a lamp heater are preferably used.
As described above, the carrier gas 141 is mixed with the raw material mist 422 formed in the film-forming atomizer 100 to be the mixed gas 142, transferred into the film-forming chamber 431 of the film-forming device 430, and a film is formed on the base substrate 434.
The base substrate 434 is not particularly limited as long as it can support a film to be formed. A material of the base substrate 434 is also not particularly limited, and may be a known material, may be an organic compound, or may be an inorganic compound. Examples thereof include a polysulfone, a polyether sulfone, a polyphenylene sulfide, a polyether ether ketone, a polyimide, a polyether imide, a fluororesin, metals such as iron, aluminum, stainless steel, and gold, silicon, sapphire, quartz, glass, calcium carbonate, lithium tantalate, lithium niobate, gallium oxide, SiC, ZnO, and GaN, and the material is not limited thereto. Examples of a shape of the base substrate 434 include a flat plate and a disk plate, and any one of them may be used. Although not particularly limited, a base substrate 434 having an area of 5 cm2 or more, more preferably 10 cm2 or more, and a thickness of 50 to 2000 μm, more preferably 100 to 800 μm is preferably used in the present invention. As a modified example, a fibrous, bar, cylindrical, prism, tubular, spiral, spherical, or ring substrate may also be used instead of the base substrate 434.
The inventive film-forming apparatus may further include a ventilation means 440 illustrated in
Although described in
The nozzle 531 is not particularly limited as long as it is configured to receive the mixed gas 142 from the film-forming atomizer 100 and to discharge it as the mixed gas 533.
The film-forming device 530 may include a ventilation means 535. The ventilation means 535 may be integrated with the nozzle 531 as illustrated in
Should be noted that in
[Film-Forming Method]
The inventive film-forming method is a film-forming method for supplying a raw material mist to a film-forming device and forming a thin film on a base substrate provided on the film-forming device, the method including:
Such a film-forming method, which involves the inventive film-forming atomizer, can stably and continuously form a film on a large-size substrate requiring a longer time, and can stably form a film with high productivity.
In the inventive film-forming method, any of the film-forming atomizers 100, 200, and 300 illustrated in
Hereinafter, an example of the inventive film-forming method will be described with reference to
In this example, the raw material mist 422 is supplied to the film-forming device 430 and a thin film is formed on the base substrate 434 provided in the film-forming device 430.
First, the raw material liquid 114 is atomized by the film-forming atomizer 100 to generate the raw material mist 422.
Then, in the film-forming atomizer 100, the atomized raw material liquid (raw material mist 422) and the carrier gas 141 are mixed to form the mixed gas 142. The carrier gas 141 is supplied from the carrier gas supplier 414 to the film-forming atomizer 100 through the pipe 413.
Thereafter, the mixed gas 142 is supplied from the film-forming atomizer 100 to the film-forming device 430 through the pipe 424. Thereby, the mixed gas 142 is supplied onto the base substrate 434 provided in the film-forming device 430 and film-forming is performed.
For other details about the film-forming method using the film-forming apparatus 400 illustrated in
Hereinafter, the present invention will be specifically described by using Examples and Comparative Examples, but the present invention is not limited thereto.
In Example 1, according to the following procedure, a raw material liquid 114 was atomized by using the film-forming atomizer 100 illustrated in
First, weighed pure water was filled into a raw material container 111 as the raw material liquid 114. A gas cylinder filled with nitrogen gas and a carrier gas inlet port 113 were connected to each other with a tube made of a urethane resin. A mist trap was further provided, and the mist trap and a tubular member 112 were connected to each other with a pipe made of PFA.
Water was filled in a propagation vessel 121 as an intermediate liquid 126.
In the film-forming atomizer 100 thus provided, the pure water 114 in the raw material container 111 was atomized (formed into mist) by propagating ultrasonic wave vibration through the water 126 with two ultrasonic wave vibrators (frequency: 2.4 MHz) as an ultrasonic wave generators 122. In the same time, the water 126 in the propagation vessel 121 was circulated with a circulator as a circulation mechanism 131 with maintaining the temperature at 25° C.
Then, nitrogen gas as a carrier gas 141 was added into the raw material container 111 at a flow rate of 5 L/min for transferring a mixed gas 142 was transferred to the mist trap and the raw material mist was recovered.
The mixed gas 142 was discharged for 5 hours with continuously refilling water so as to maintain the water level of the water 114 in the raw material container 111, and then the atomization was finished.
Thereafter, the water recovered by the mist trap was weighed.
In Comparative Example 1, an atomizer without the circulation mechanism 131 was used. That is, the atomization was performed in the same manner as in Example 1 except that: the water 126 in the propagation vessel 121 was not circulated; and the temperature of the water in the propagation vessel 121 was maintained at 25° C. with an immersion chiller.
Thereafter, the water recovered by the mist trap was weighed.
Table 1 shows the amounts of the recovered water obtained in Example 1 and Comparative Example 1.
It is found from Table 1 that the film-forming atomizer 100 of Example 1, an example of the inventive film-forming atomizer, can generate a larger amount of mist than the atomizer of Comparative Example 1, which includes no circulation mechanism.
In Example 2, an α-gallium oxide film was formed by using the film-forming apparatus 400 illustrated in
More specifically, used as the film-forming atomizer 100 was an apparatus including the raw material container 111 and the tubular member 112, both of them was made of borosilicate glass. A film-forming device 430 including a film-forming chamber 431 made of quartz was also provided. For a carrier gas supplier 411, a gas cylinder filled with nitrogen gas was used. The gas cylinder 411 and the film-forming atomizer 100 were connected to each other with a tube 413 made of a urethane resin, and the film-forming atomizer 100 and the film-forming device 430 were connected to each other with a pipe 424 made of quartz.
With the film-forming apparatus 400 thus provided, prepared as the raw material liquid 114 was a solution in which hydrochloric acid at concentration of 34% was added at a volume ratio of 1% to a 0.02 mol/L aqueous solution of gallium acetylacetonate to be stirred with a stirrer for 60 minutes. This raw material liquid 114 was filled in the raw material container 111.
Water as the intermediate liquid 126 was filled in the propagation vessel 121.
Then, as the base substrate 434, a c-face sapphire substrate with 0.6 mm in thickness and 4 inch in diameter was mounted on a susceptor 432 made of quartz provided in the film-forming chamber 431. The sapphire substrate was heated by using the heating means 433 so that a substrate temperature was to be 500° C.
Then, the raw material liquid 114 in the raw material container 111 was atomized (formed into mist) by propagating ultrasonic wave vibration through the water 126 with two ultrasonic wave vibrators (frequency: 2.4 MHz) as the ultrasonic wave generators 122, and a raw material mist 422 was generated. In the same time, the water 126 in the propagation vessel 121 was circulated with a circulator as the circulation mechanism 131 with maintaining the temperature at 25° C.
Then, nitrogen gas was added from the gas cylinder 411 into the raw material container 111 at a flow rate of 5 L/min for supplying the mixed gas 142 of the raw material mist 422 and the nitrogen gas 141 to the film-forming chamber 431 for 120 minutes and film-forming was performed. Immediately thereafter, the supply of the nitrogen gas was stopped to stop the supply of the mixed gas 142 to the film-forming chamber 431, and the base substrate 434 was taken out.
Thereafter, the above film formation was repeated four times using new substrates.
During the above five-time film formation, the raw material liquid 114 was continuously atomized without stop with refilling the raw material liquid 114.
The formed film, which was measured by X-ray diffraction to appear a peak at 2θ=40.3°, was confirmed to be α-phase Ga2O3.
Thereafter, of all the five formed sample films, thicknesses at nine positions in the substrate surface were measured by light reflectance analysis.
In Comparative Example 2, an atomizer without the circulation mechanism 131 was used. That is, the film formation was performed in the same manner as in Example 2 except that: the water 126 in the propagation vessel 121 was not circulated; and the temperature of the water in the liquid vessel was maintained at 25° C. with an immersion chiller.
The formed film, which was measured by X-ray diffraction to appear a peak at 2θ=40.3°, was confirmed to be α-phase Ga2O3.
Thereafter, of all the five formed sample films, thicknesses at nine positions in the substrate surface were measured by light reflectance analysis.
The following Table 2 shows the thicknesses of the obtained films in Example 2 and Comparative Example 2. The thickness shown in Table 2 is an average value of the thicknesses at the nine positions.
As shown in Table 2, the film formation performed with the film-forming apparatus of Example 2, an example of the inventive film-forming apparatus, has a constant growth rate, and it is found that stable film formation was continuously achieved with good efficiency.
Meanwhile, as apparent from in Table 2, Comparative Example 2, which used the conventional atomizer without the circulation mechanism, decreased the growth rate with repeating film formations. It is presumed that, in Comparative Example 2, gas in the water 126 is generated and retained as bubbles on the bottom of the raw material container 111 during the atomization, and these bubbles inhibit the ultrasonic wave propagation to the raw material liquid 114.
It should be noted that the present invention is not limited to the above-described embodiments. The embodiments are just examples, and any examples that substantially have the same feature and demonstrate the same functions and effects as those in the technical concept disclosed in claims of the present invention are included in the technical scope of the present invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2020-133132 | Aug 2020 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2021/026035 | 7/9/2021 | WO |
