Gas supply device and gas supply method

Abstract

The present invention provides a gas supply device and gas supply method that can stably supply concentrated gas, which is a concentrated form of product gas. [Solution] The supply device 100 comprises a gas separation membrane 1 that permeates the product gas, a gas separation container 2 that houses the separation membrane 1, and a heating device 20 that heats the separation membrane 1. The gas separation container 2 has a first space 31 that stores a mixed gas of carrier gas and product gas as raw material gas, a second space 32 partitioned from the first space 31 by the separation membrane 1, a raw material gas inlet 41 that communicates with the first space 31 and introduces the raw material gas into the first space 31, and an outlet 42 that communicates with the second space 32 and sends out concentrated gas from the second space 32 in which the product gas has been concentrated.

Description

Technical Field

[0001] The present invention relates to a gas supply device and a gas supply method.

Background Art

[0002] Due to the high integration of semiconductors, it is necessary to lower the temperature and improve the throughput of the semiconductor manufacturing process. To improve this throughput, highly reactive gases such as hydrogen peroxide and hydrazine are required as gases for semiconductor materials. However, these highly reactive gases are likely to decompose during transportation and storage. Therefore, these highly reactive gases may be transported and stored in the form of a solution in which these gases are dissolved in water or an organic solvent in order to suppress decomposition during transportation and storage. For example, hydrogen peroxide may be transported and stored in an aqueous solution state, and hydrazine may be transported and stored in a mixture (solution) state with an organic solvent.

[0003] When a highly reactive gas is in a solution state as described above, it is necessary to separate these gases from this solution when using the highly reactive gas. However, when separating and using a highly reactive gas from such a solution, problems have arisen such that the concentration of these gases becomes low or the vapor of the solvent is mixed into these gases. Therefore, for example, as disclosed in Patent Document 1, a concentrated gas with an increased concentration may be obtained using a separation membrane, and this concentrated gas may be supplied to a device that uses the gas.

[0004] Patent Document 1 discloses a supply method and supply apparatus for supplying gaseous materials (product gas) used, for example, in the manufacture of semiconductor devices. This supply method includes a mixed gas preparation step of introducing a carrier gas into a container containing the material in solid or liquid form to obtain a mixed gas of the vaporized material and the carrier gas; a concentration step of obtaining a concentrated gas by increasing the concentration of the material in the mixed gas using a separation membrane; and a supply step of supplying the concentrated gas to an apparatus that uses the material. In this supply method, the carrier gas in the mixed gas permeates through the separation membrane, increasing the concentration of the material in the supplied mixed gas and resulting in a concentrated gas. Patent Document 1 discloses that, for example, gaseous materials used in the manufacture of semiconductor devices require high concentration. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2024-118353 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] In supply methods and supply devices such as those disclosed in Patent Document 1, it was sometimes not possible to stably increase the concentration (concentrate) of the product gas. For example, when the product gas is a highly reactive gas with a highly polar molecular structure (polar molecule) that has a permanent dipole moment, such as hydrazine or hydrogen peroxide, it was sometimes difficult to stably increase the concentration of these gases. In particular, it was sometimes difficult to stably increase the concentration of these gases over a long period of time (i.e., continuously).

[0007] More specifically, when a silica separation membrane is used as a separation membrane for concentrating highly reactive gases (product gases) such as hydrazine and hydrogen peroxide, the silica separation membrane reacts with the hydrazine and hydrogen peroxide over time, changing the structure of the separation membrane (pore structure). As a result, the permeability of the carrier gas through this separation membrane decreases, making it difficult to stably concentrate these gases to high concentrations. In particular, it was difficult to stably concentrate these gases to high concentrations over long periods.

[0008] Furthermore, when using zeolite membranes or metal-organic framework (MOF) membranes as separation membranes to concentrate gases with highly polar molecular structures (polar molecules) that have a permanent dipole moment, such as hydrazine or hydrogen peroxide, the pores of the zeolite or MOF become clogged due to the adsorption of hydrazine or hydrogen peroxide (i.e., polar molecules). As a result, the permeability of the carrier gas through this separation membrane decreases, making it difficult to stably increase the concentration of these gases to high levels. In particular, it was sometimes difficult to stably increase the concentration of these gases to high levels over long periods.

[0009] Furthermore, the same was true even when attempting to increase the concentration of a highly reactive gas, such as hydrazine or hydrogen peroxide, or a gas with a highly polar molecular structure, by permeating the separation membrane instead of using a carrier gas.

[0010] Given this background, there is a need for a gas supply device and gas supply method that can stably supply concentrated gas, which is a concentrated form of product gas, over a long period of time.

[0011] The present invention has been made in view of the above circumstances, and its object is to provide a gas supply device and a gas supply method that can stably supply concentrated gas, which is a concentrated product gas. [Means for solving the problem]

[0012] The gas supply device according to the present invention for achieving the above objective is: A gas separation membrane that permeates the product gas, A gas separation container containing the separation membrane, The system includes a heating device for heating the separation membrane, The aforementioned gas separation container is A first space for storing the gas containing the aforementioned product gas as a raw material gas, The first space and the second space separated by the separation membrane, A raw material gas inlet that communicates with the first space and introduces the raw material gas into the first space, It has an outlet that communicates with the second space and discharges concentrated gas, which is the product gas concentrated from the second space.

[0013] The gas supply method according to the present invention for achieving the above objective is: A concentration step in which a gas containing the product gas is brought into contact with a separation membrane as a raw material gas, the product gas is concentrated from the raw material gas by permeating through the separation membrane, and the concentrated gas containing the product gas is discharged. The process includes a heating step of heating the separation membrane, The heating step is performed during the concentration step. [Effects of the Invention]

[0014] According to this disclosure, it is possible to provide a gas supply device and a gas supply method that can stably supply concentrated product gas. [Brief explanation of the drawing]

[0015] [Figure 1] This is an explanatory diagram of the configuration of the gas supply device (supply device) according to this embodiment. [Figure 2] This is an explanatory diagram of a gas separation vessel and separation membrane. [Figure 3] This is a diagram illustrating a different gas separation container and separation membrane. [Modes for carrying out the invention]

[0016] Based on the drawings, a gas supply device and a gas supply method according to an embodiment of the present invention will be described.

[0017] First, an overview of the gas supply device and the gas supply method according to the present embodiment will be described.

[0018] FIG. 1 shows an explanatory diagram of the configuration of a supply device 100, which is an example of the gas supply device according to the present embodiment.

[0019] As shown in FIG. 1, the supply device 100 includes a gas separation membrane 1 that permeates the product gas, a gas separation container 2 that houses the gas separation membrane 1, and a heating device 20 that heats the gas separation membrane 1. The gas separation container 2 has a first space portion 31 that stores a gas containing the product gas as a raw material gas, a second space portion 32 partitioned from the first space portion 31 by the gas separation membrane 1, a raw material gas inlet 41 that communicates with the first space portion 31 and introduces the raw material gas into the first space portion 31, and an outlet 42 that communicates with the second space portion 32 and sends out a concentrated gas in which the product gas is concentrated from the second space portion 32.

[0020] The gas supply method according to the present embodiment includes a concentration step of bringing a mixed gas of a carrier gas and a product gas into contact with the gas separation membrane 1 as a raw material gas, permeating the gas separation membrane 1 to concentrate the product gas from the raw material gas, and sending out the concentrated gas in which the product gas is concentrated, and a heating step of heating the gas separation membrane 1. The heating step is performed during the concentration step.

[0021] According to the supply device 100, a concentrated gas in which the product gas is concentrated can be stably supplied. That is, according to the supply device 100, the permeability of the product gas in the gas separation membrane 1 is maintained over a long period, and thereby, stable supply of the concentrated gas over a long period is realized.

[0022] Similarly, according to the gas supply method of this embodiment, concentrated gas, in which the product gas has been concentrated, can be stably supplied. That is, according to the gas supply method of this embodiment, the permeability of the product gas in the separation membrane 1 is maintained over a long period of time, thereby realizing a stable supply of concentrated gas, in which the product gas has been concentrated, over a long period of time. The gas supply method of this embodiment can be realized, for example, by a supply device 100.

[0023] The supply device 100 will be described in detail below. Furthermore, the gas supply method according to this embodiment will be described in detail, with an example of the case in which the supply device 100 is used.

[0024] The supply device 100 is a device for supplying concentrated gas, which is a gas obtained by separating the product gas at a high concentration from the raw material gas supplied from the upstream device, etc., to the downstream device, etc. (for example, semiconductor manufacturing equipment). In this embodiment, the raw material gas is a gas containing the components of the product gas, and one example is a mixed gas of product gas and carrier gas. The concentrated gas is a gas that contains product gas at a higher concentration than the raw material gas. The concentrated gas may contain the carrier gas that was contained in the raw material gas. In other words, the mixing of carrier gas into the concentrated gas is permissible. Also, gas means being in a gaseous state. In this embodiment, the concept of gas includes the concept of vapor.

[0025] Examples of product gases are highly reactive gases. For example, hydrazine and hydrogen peroxide are highly reactive gases that are in high demand in semiconductor manufacturing processes, that is, are frequently used in semiconductor manufacturing processes.

[0026] Another example of product gases is gases with highly polar molecular structures. Examples of highly polar gases with large demand in semiconductor manufacturing processes include water (water vapor), hydrogen peroxide, ammonia, hydrazine, formaldehyde, methanol, and hydroxylamine.

[0027] Preferred carrier gases are hydrogen, nitrogen, oxygen, helium, argon, and mixtures of at least two of these gases.

[0028] The product gas contained in the raw material gas may be obtained by volatilizing a raw material liquid, which is a liquid containing the components of the product gas (raw material components). Examples of raw material liquids include liquefied product gas, aqueous solutions of the components of the product gas, and solutions obtained by dissolving the components of the product gas in an organic solvent.

[0029] The supply device 100 may, for example, include a separation membrane 1, a gas separation container 2, a heating device 20, a temperature sensor 29 for measuring the temperature of the separation membrane 1, a concentration sensor 79 for measuring the concentration of product gas in the concentrated gas, a pressure control device 78 for controlling (adjusting) the pressure in the first space 31 (the pressure of the raw material gas in the space of the first space 31), and a product gas concentration adjustment mechanism 6 for controlling the concentration of product gas in the concentrated gas.

[0030] The separation membrane 1 is a membrane-like component that allows the product gas in the raw material gas to permeate from one side of the membrane to the other side, while preventing the carrier gas in the raw material gas from permeating, or making it extremely difficult for the carrier gas to permeate. In other words, the separation membrane 1 is a membrane-like component that can separate (extract) the product gas from the raw material gas at a high concentration. By using the separation membrane 1, it is possible to separate the product gas from the raw material gas at a high concentration by allowing the product gas to permeate through the separation membrane 1, and to obtain concentrated gas in which the product gas is concentrated.

[0031] In the following, the process of separating the product gas from the raw material gas at a high concentration by permeating through separation membrane 1, and obtaining concentrated gas from which the product gas is concentrated, may be simply described as "concentrating," "concentrating the product gas," or "obtaining concentrated gas from the raw material gas."

[0032] The type of membrane used for separation membrane 1 may be appropriately selected depending on the type of product gas to be concentrated and the type of carrier gas. It is preferable that separation membrane 1 does not allow gases other than the product gas to permeate, or allows them to permeate very little.

[0033] Suitable membrane members for separation membrane 1 include zeolite membranes and organometallic structure membranes (membranes formed from organometallic structure (MOF) materials). These membranes are particularly suitable for separating gases with highly polar molecular structures, such as hydrazine and hydrogen peroxide, because they have a high ability to selectively adsorb polar molecules. Separation membrane 1 may be a membrane member comprising at least one of the zeolite membrane and the organometallic structure membrane.

[0034] Among zeolite membranes, particularly preferred are CHA-type zeolite membranes, such as those using high-silica CHA-type zeolite based on porous aluminum oxide, for example, ZEBREX® ZX1 and ZX3 manufactured by Mitsubishi Chemical Corporation. The use of membranes using MFI-type zeolite is also not excluded. When a zeolite membrane is used as a separation membrane 1, molecules with a molecular diameter smaller than the pore diameter of the zeolite constituting the zeolite membrane and high polarity are preferentially adsorbed to the zeolite membrane and permeate through this membrane.

[0035] CHA-type zeolite membranes are suitable for concentrating gases such as water, hydrogen peroxide, ammonia, hydrazine, formaldehyde, methanol, and hydroxylamine, which are polar molecules whose molecular size (distance from end to end of the widest part of the molecule) is smaller than the pore size of CHA-type zeolite (0.38 nm to 0.40 nm).

[0036] MFI-type zeolite membranes are suitable for concentrating not only polar gas molecules with a molecular size smaller than the pore size of CHA-type zeolites, but also gases with a molecular size smaller than the pore size of MFI-type zeolites (0.55 nm), such as formic acid, ethanol, acetone, and carbonyl fluoride.

[0037] Among organometallic structure membranes, those particularly suitable are those containing a CN-bridged complex skeleton in their molecular structure, which exhibits strong metal-organic molecular bonding in its internal structure. By using an organometallic structure membrane containing a CN-bridged complex skeleton (organometallic structure membrane) as separation membrane 1, structural changes in separation membrane 1 are suppressed, enabling the stable supply of concentrated gas over a long period.

[0038] In this embodiment, "stable supply of concentrated gas" includes cases where the concentration of product gas in the concentrated gas fluctuates little over time, where the amount of product gas permeating through the separation membrane 1 fluctuates little over time, and where there is little variation in concentration being possible or not.

[0039] As shown in Figures 1 and 2, the gas separation container 2 is a container in which the separation membrane 1 is housed in its internal space.

[0040] The gas separation container 2 can have any shape as long as it has an internal space to accommodate the separation membrane 1, but it may be formed in a cylindrical or rectangular shape, for example. Figure 2 shows an example where the gas separation container 2 is formed in a cylindrical shape.

[0041] As shown in Figures 1 and 2, the internal space of the gas separation container 2 is divided into a first space 31 and a second space 32 by a separation membrane 1. In Figure 2, the separation membrane 1 is formed in a flat plate shape and is positioned so as to intersect (orthogonal in Figure 2) with the axial direction of the cylindrical gas separation container 2, illustrating a case in which the internal space of the gas separation container 2 is divided into a first space 31 located on one side in the axial direction of the gas separation container 2 and a second space 32 located on the other side in the axial direction of the gas separation container 2.

[0042] The gas separation container 2 may be made of a metal alloy such as an iron alloy, or a corrosion-resistant resin such as fluororesin.

[0043] As shown in Figure 1, the gas separation container 2 includes a raw material gas inlet 41 for introducing raw material gas (gas G2) into the first space 31, an exhaust port 43 for exhausting unwanted gas (waste gas, gas G4) from the first space 31 to the system of the supply device 100, and an outlet 42 for sending out concentrated gas (gas G3) from the second space 32. The gas separation container 2 may further have a sweep gas inlet 45 for introducing sweep gas into the second space 32. When sweep gas is introduced into the second space 32, the sweep gas may be of the same type as the gases preferred as carrier gases listed above as examples. Also, when sweep gas is introduced into the second space 32, the concentrated gas sent out from the outlet 42 may further contain sweep gas.

[0044] The first space 31 is a spatial region partitioned by the inner wall of the gas separation container 2 and the separation membrane 1, or a spatial region partitioned by the separation membrane 1, for storing the raw material gas introduced from the raw material gas inlet 41.

[0045] The second space 32 is a separate spatial region from the first space 31 within the internal space of the gas separation container 2, which is partitioned by the inner wall of the gas separation container 2 and the separation membrane 1, or partitioned by the separation membrane 1, for receiving the raw material gas (concentrated gas) that has permeated through the separation membrane 1.

[0046] The second space 32 is adjacent to the first space 31 via the separation membrane 1.

[0047] When the product gas contained in the raw material gas stored in the first space 31 comes into contact with the separation membrane 1, it is adsorbed onto the separation membrane 1, diffuses within the separation membrane 1, permeates through the separation membrane 1, reaches the side of the second space 32, and is desorbed from the separation membrane 1 and concentrated (an example of a concentration process). That is, concentrated gas containing a high concentration of product gas separated (concentrated) from the raw material gas stored in the first space 31 by the separation membrane 1 flows into the second space 32.

[0048] The concentrated gas that flows into the second space 32 is sent to downstream equipment (for example, semiconductor manufacturing equipment 9) via the outlet 42, which will be described later. In other words, in the gas separation container 2, a concentration process is realized in which the raw material gas in the first space 31 is brought into contact with the separation membrane 1, the product gas is concentrated from the raw material gas by permeating through the separation membrane 1, and the concentrated gas is sent out from the second space 32.

[0049] The raw material gas inlet 41 is an inlet for introducing raw material gas from the raw material container 70 into the first space 31. The raw material gas inlet 41 connects the raw material gas supply pipe 72, which is a pipe that supplies raw material gas from the raw material container 70 to the first space 31, to the first space 31, thereby enabling the introduction of raw material gas from the raw material container 70 and the raw material gas supply pipe 72 into the first space 31.

[0050] The outlet 42 is an outlet that sends concentrated gas (gas G3) from the second space 32 to equipment downstream of the process (for example, semiconductor manufacturing equipment 9). The outlet 42 connects the concentrated gas supply pipe 74, which is piping that supplies concentrated gas to equipment downstream of the process, to the second space 32.

[0051] The exhaust port 43 is an outlet for exhausting the raw material gas stored in the first space 31 as waste gas to the outside of the supply device 100 system. The exhaust port 43 connects the first space 31 to the waste gas pipe 73, which is a pipe that leads the waste gas to a waste gas treatment device or the like.

[0052] In the gas separation container 2, the components of the raw material gas stored in the first space 31 are separated by the separation membrane 1, thereby reducing the product gas components in the raw material gas stored in the first space 31. Therefore, new raw material gas is introduced into the first space 31, for example, continuously, through the raw material gas inlet 41. The raw material gas in the first space 31, from which the product gas components have been reduced, is then discharged outside the system as waste gas (gas G3) through the exhaust port 43 and the waste gas pipe 73.

[0053] The sweep gas inlet 45 is an inlet for introducing sweep gas (gas G5) into the second space 32. The sweep gas inlet 45 connects the sweep gas supply pipe 75, which is the piping that supplies the sweep gas, to the second space 32, making it possible to introduce the sweep gas into the second space 32.

[0054] Ports and piping such as the raw gas inlet 41, outlet 42, exhaust port 43, sweep gas inlet 45, raw gas supply pipe 72, exhaust gas pipe 73, and concentrated gas supply pipe 74 may be made of, for example, a metal alloy such as an iron alloy or a corrosion-resistant resin such as a fluororesin.

[0055] The concentration sensor 79 is a device for measuring the concentration of product gas contained in concentrated gas (gas G3). The concentration sensor 79 may be appropriately selected depending on the type of product gas, and any type that can measure the concentration of product gas contained in the mixed gas is acceptable. As an example, the concentration sensor 79 may be an optical gas concentration meter using ultraviolet light (e.g., vacuum ultraviolet light) or infrared light, or an ultrasonic gas concentration meter.

[0056] The concentration sensor 79 may be installed, for example, in the concentrated gas supply pipe 74 to measure the concentration of the product gas contained in the concentrated gas flowing through the concentrated gas supply pipe 74.

[0057] In this embodiment, in order to reduce pressure loss between the gas separation container 2 and the equipment downstream of the supply device 100 (semiconductor manufacturing equipment 9) (i.e., the concentrated gas supply pipe 74), it is preferable not to install equipment that increases the flow resistance of concentrated gas, such as a flow rate control device or a pressure regulating device, in the concentrated gas supply pipe 74. The flow rate of concentrated gas flowing through the concentrated gas supply pipe 74 can be controlled by adjusting the pressure difference between the pressure in the space on the first space section 31 side (pressure of raw material gas or waste gas) and the pressure in the space on the second space section 32 side (pressure of concentrated gas) (hereinafter referred to as the pressure difference in the separation membrane 1) and the temperature of the separation membrane 1.

[0058] To adjust the flow rate of concentrated gas passing through the concentrated gas supply pipe 74, in other words, to adjust the pressure difference in the separation membrane 1, the supply device 100 may be equipped with a pressure control device 78 that adjusts the pressure in the first space 31. The pressure in the first space 31 refers to the pressure of the raw material gas within the space of the first space 31, or more precisely, the pressure of the raw material gas in contact with the separation membrane 1.

[0059] The pressure control device 78 may, for example, be a flow control valve or pressure regulating valve that adjusts the pressure of the exhaust gas discharged from the exhaust port 43, and may be installed in the exhaust gas pipe 73, for example.

[0060] Specifically, by reducing the valve opening of the pressure control device 78 and increasing the pressure in the first space 31, the pressure difference across the separation membrane 1 can be increased, thereby increasing the flow rate of concentrated gas flowing through the concentrated gas supply pipe 74. Conversely, by increasing the valve opening of the pressure control device 78 and decreasing the pressure in the first space 31, the pressure difference across the separation membrane 1 can be reduced, thereby decreasing the flow rate of concentrated gas flowing through the concentrated gas supply pipe 74. In other words, the pressure control device 78 can adjust the pressure difference across the separation membrane 1, and by adjusting this pressure difference across the separation membrane 1, the flow rate of concentrated gas flowing through the concentrated gas supply pipe 74 can be adjusted.

[0061] The raw material container 70 is a container that stores the materials for the product gas, such as the components of the raw material gas, or the raw material liquid that serves as the source of the product gas to be contained in the raw material gas, and supplies the raw material gas to the gas separation container 2. In this embodiment, the raw material container 70 has a carrier gas inlet 70a into which the carrier gas is supplied, and a raw material outlet 70b into which the raw material gas is discharged.

[0062] In this embodiment, the raw material container 70 is connected to a carrier gas inlet 70a by a carrier gas piping 71, and is supplied with carrier gas (gas G1) from a carrier gas supply source (e.g., a gas cylinder) located upstream of the process, via the carrier gas inlet 70a.

[0063] In the raw material container 70, for example, a mixing process may be performed in which a mixed gas is obtained by mixing a carrier gas supplied via the carrier gas piping 71 with a product gas generated from the material of the product gas, and this mixed gas is used as the raw material gas. The carrier gas piping 71 may be provided with a carrier gas supply control device 77 that controls (adjusts) the amount of carrier gas supplied to be included in the raw material gas.

[0064] The carrier gas supply control device 77 is a control device that controls the amount of carrier gas supplied to the raw material container 70 via the carrier gas piping 71. The carrier gas supply control device 77 is, for example, a valve device such as an air pump, a flow control valve, or a pressure regulating valve.

[0065] In this embodiment, the raw material container 70 may supply raw material gas (gas G2) to the raw material gas supply pipe 72 connected to the raw material outlet 70b via the raw material outlet 70b.

[0066] The heating device 20 is a device equipped with a heating mechanism and heat source for heating the separation membrane 1 (an example of a heating process). The heating device 20 may heat the separation membrane 1 and the raw material gas stored in the first space 31 via the gas separation container 2. In other words, the heating device 20 may heat the gas separation container 2. Alternatively, the heating device 20 may heat the raw material gas. The heating device 20 can heat the separation membrane 1 by heating the gas separation container 2 and the raw material gas. Of course, the heating device 20 may also directly heat the separation membrane 1.

[0067] The heating device 20 may, for example, use an electric heater or a steam heater as a heating mechanism or heat source. The heating device 20 may also be a device that uses a heating mechanism that utilizes electromagnetic induction or radiant heat transfer.

[0068] The heating device 20 may be installed on the gas separation container 2, for example, so as to cover at least a portion of the outer surface of the gas separation container 2, and this configuration is illustrated in Figure 1.

[0069] In the supply device 100 of this embodiment, the heating device 20 can heat the gas separation container 2, the separation membrane 1, and the raw material gas. This makes it easier for the product gas in the raw material gas to permeate the separation membrane 1 more selectively.

[0070] Specifically, when the separation membrane 1 is heated, components of the product gas are selectively adsorbed onto the separation membrane 1, making it easier for the product gas to selectively permeate through the separation membrane 1. The components of the product gas adsorbed onto the separation membrane 1 are further facilitated by the heating of the separation membrane 1, as surface diffusion of the product gas components within the separation membrane 1 is promoted, thereby accelerating permeation through the separation membrane 1. The components of the product gas that have permeated from the first space 31 to the second space 32 of the separation membrane 1 are further detached from the separation membrane 1 and diffused into the second space 32, especially when the separation membrane 1 is heated. The promotion of detachment and diffusion of product gas components on the second space 32 side of the separation membrane 1 makes it even easier for the product gas to selectively permeate through the separation membrane 1.

[0071] In this way, the heating process during the concentration process improves the efficiency of concentrating the product gas from the raw material gas. Specifically, the heating process during the concentration process prevents the raw material gas molecules adsorbed on the separation membrane 1 from remaining adsorbed (making the adsorption of raw material gas molecules onto the separation membrane 1 irreversible), thus preventing blockage of the separation membrane 1 and allowing the concentration of the product gas from the raw material gas to continue stably for a long period of time.

[0072] In this embodiment, high concentration efficiency includes cases where the concentration of the product gas in the concentrated gas is high, or where the amount of product gas permeating through the separation membrane 1 is large.

[0073] Furthermore, by suppressing the continued adsorption of the product gas onto the separation membrane 1, the reaction between the product gas and the separation membrane 1 is suppressed, and changes in the structure of the separation membrane (pore structure) are also suppressed, thus enabling the concentration of the product gas from the raw material gas to be continued stably for a long period of time.

[0074] The heating device 20 heats the gas separation container 2 to, for example, 30°C to 200°C, preferably 30°C to 150°C, and more preferably 40°C to 120°C. That is, the heating device 20 heats the separation membrane 1 to 30°C to 200°C, preferably 30°C to 150°C, and more preferably 40°C to 120°C.

[0075] By keeping the separation membrane 1 within a temperature range of 30°C to 200°C, the product gas permeates the separation membrane 1 more effectively, resulting in efficient concentration of the product gas. Furthermore, the permeation of the carrier gas through the separation membrane 1 is effectively suppressed, making it easier to increase the concentration of the product gas in the concentrated gas, thus efficiently concentrating the product gas. Additionally, the concentration of the product gas from the raw material gas can be sustained more stably over a longer period.

[0076] Furthermore, the efficiency of product gas concentration may be further increased by setting the temperature of the separation membrane 1 within the range of 30°C to 150°C. Also, the efficiency of product gas concentration may be even higher by setting the temperature of the separation membrane 1 within the range of 40°C to 120°C. In other words, within this temperature range, the ease of permeation of the product gas through the separation membrane 1 may be greatest compared to the ease of permeation of the carrier gas through the separation membrane 1 (the selectivity ratio may be maximized). Additionally, it may be possible to continue the concentration of product gas from the raw material gas stably for an even longer period.

[0077] The heating device 20 may control the amount of heating to maintain the gas separation container 2, the separation membrane 1, or the first space 31 at a constant temperature, or to reach a predetermined target temperature. In this case, the heating device 20 may attach temperature sensors to the gas separation container 2, the separation membrane 1, or the first space 31 to measure their temperatures, and control the amount of heating to them based on the measurement results of these temperature sensors (so-called feedback control). For example, a temperature sensor 29 may be installed on the separation membrane 1 to measure its temperature, and the heating device 20 may control the amount of heating to heat the separation membrane 1 (gas separation container 2, raw gas) based on the temperature of the separation membrane 1 measured by this temperature sensor 29. In this way, the heating device 20 can control the temperature of the separation membrane 1.

[0078] The temperature of the separation membrane 1 may be determined by measuring the temperature of the raw material gas stored in the first space 31. For example, the temperature of the raw material gas stored in the first space 31 may be considered as the temperature of the separation membrane 1. Specifically, in order to measure the temperature of the separation membrane 1, a temperature sensor that measures the temperature inside the first space 31 (i.e., the temperature of the raw material gas stored in the first space 31) may be provided in the gas separation container 2.

[0079] The product gas concentration adjustment mechanism 6 is a mechanism that controls the concentration of product gas in the concentrated gas that is sent to downstream equipment (semiconductor manufacturing equipment 9) via the outlet 42.

[0080] As an example, the product gas concentration adjustment mechanism 6 may control the concentration of the product gas in the raw material gas based on the concentration of the product gas in the concentrated gas measured by the concentration sensor 79.

[0081] In this embodiment, the product gas concentration adjustment mechanism 6 may, as an example, include at least one of the above-mentioned raw material container 70 and carrier gas supply control device 77, heating device 20, and pressure control device 78 as its components.

[0082] When the product gas concentration adjustment mechanism 6 includes a raw material container 70 and a carrier gas supply control device 77, the concentration of the product gas in the concentrated gas is controlled as follows.

[0083] In this case, the product gas concentration adjustment mechanism 6 adjusts the pump output and valve opening of the carrier gas supply control device 77 based on the concentration of product gas in the concentrated gas measured by the concentration sensor 79, thereby adjusting the amount of carrier gas supplied to the raw material container 70 and controlling the concentration of product gas in the raw material gas. In other words, the carrier gas supply control device 77 can control the concentration of product gas in the raw material gas by adjusting the amount of carrier gas supplied to the raw material container 70 based on the concentration of product gas in the concentrated gas measured by the concentration sensor 79.

[0084] The concentration of product gas in the concentrated gas can be adjusted by controlling the concentration of product gas in the raw material gas, as performed by the product gas concentration adjustment mechanism 6. For example, the concentration of product gas in the concentrated gas can be kept constant.

[0085] Specifically, when the concentration of product gas in the concentrated gas measured by the concentration sensor 79 falls below the target value, the product gas concentration adjustment mechanism 6 reduces the pump output of the carrier gas supply control device 77 or decreases the valve opening, thereby reducing the amount of carrier gas supplied to the raw material container 70, increasing the concentration of product gas in the raw material gas, and thus raising the concentration of product gas in the concentrated gas.

[0086] Furthermore, if the concentration of product gas in the concentrated gas measured by the concentration sensor 79 exceeds the target value, the product gas concentration adjustment mechanism 6 increases the pump output of the carrier gas supply control device 77 or widens the valve opening, thereby increasing the amount of carrier gas supplied to the raw material container 70, lowering the concentration of product gas in the raw material gas, and thus reducing the concentration of product gas in the concentrated gas.

[0087] When the product gas concentration adjustment mechanism 6 includes a heating device 20, the concentration of the product gas in the concentrated gas is controlled as follows.

[0088] In this case, the product gas concentration adjustment mechanism 6 may control the amount of heating the separation membrane 1 by the heating device 20 based on the detection result of the concentration of product gas contained in the concentrated gas by the concentration sensor 79. That is, the heating device 20 may control the amount of heating the separation membrane 1 based on the concentration of product gas in the concentrated gas measured by the concentration sensor 79.

[0089] In this case, the amount of heating by the heating device 20 (product gas concentration adjustment mechanism 6) may be controlled based on the relationship between the temperature of the raw material gas stored in the first space 31 (temperature of the separation membrane 1) and the ease with which the product gas and carrier gas permeate the separation membrane 1.

[0090] In other words, the heating amount controlled by the heating device 20 (product gas concentration adjustment mechanism 6) may be based on the temperature in the space of the gas separation container 2, separation membrane 1, or first space section 31 (temperature of the raw material gas) and the concentration of the product gas contained in the concentrated gas. For example, the heating amount may be controlled based on the detection result of the concentration of the product gas contained in the concentrated gas while keeping the temperature of the separation membrane 1 measured by the temperature sensor 29 within a range of 30°C to 150°C.

[0091] As an example of a case where, within a certain temperature range, an increase in the temperature of the separation membrane 1 increases the concentration of the product gas contained in the concentrated gas, and a decrease in the temperature of the separation membrane 1 decreases the concentration of the product gas contained in the concentrated gas, the heating device 20 (product gas concentration adjustment mechanism 6) may control the amount of heating as follows.

[0092] For example, if the concentration of product gas in the concentrated gas is higher than the target value, the heating device 20 may reduce the amount of heating to lower the temperature of the gas separation container 2, the separation membrane 1, or the first space 31. This will lower the concentration of product gas in the concentrated gas. Alternatively, for example, if the concentration of product gas in the concentrated gas is lower than the target value, the heating device 20 may increase the amount of heating to raise the temperature of the gas separation container 2, the separation membrane 1, or the first space 31. This will increase the concentration of product gas in the concentrated gas.

[0093] Furthermore, to illustrate a case where, within a certain temperature range, a decrease in the temperature of the separation membrane 1 increases the concentration of the product gas contained in the concentrated gas, and a rise in the temperature of the separation membrane 1 decreases the concentration of the product gas contained in the concentrated gas, the heating device 20 (product gas concentration adjustment mechanism 6) may control the amount of heating as follows.

[0094] For example, if the concentration of product gas in the concentrated gas is higher than the target value, the heating device 20 may increase the amount of heating to lower the temperature of the gas separation container 2, separation membrane 1, or first space 31. This will lower the concentration of product gas in the concentrated gas. Alternatively, for example, if the concentration of product gas in the concentrated gas is lower than the target value, the heating device 20 may decrease the amount of heating to raise the temperature of the gas separation container 2, separation membrane 1, or first space 31. This will increase the concentration of product gas in the concentrated gas.

[0095] The amount of heating by the heating device 20 may be controlled so that the concentration of the product gas contained in the concentrated gas remains constant.

[0096] When the product gas concentration adjustment mechanism 6 includes a pressure control device 78, the concentration of the product gas in the concentrated gas is controlled as follows.

[0097] In this case, the product gas concentration adjustment mechanism 6 adjusts the valve opening of the pressure control device 78 based on the concentration of the product gas in the concentrated gas measured by the concentration sensor 79, thereby adjusting the pressure in the first space 31 and controlling the concentration of the product gas in the concentrated gas. That is, the pressure control device 78 can control the pressure in the first space 31 (the pressure of the raw material gas in contact with the separation membrane 1, and the pressure difference at the separation membrane 1) based on the concentration of the product gas in the concentrated gas measured by the concentration sensor 79.

[0098] The product gas concentration adjustment mechanism 6 may adjust the valve opening of the pressure control device 78 based on the relationship between the magnitude of the pressure in the first space 31 (pressure difference in the separation membrane 1) and the ease with which the product gas and carrier gas permeate the separation membrane 1.

[0099] In the supply device 100, the product gas concentration adjustment mechanism 6 may control at least one of the following based on the concentration of the product gas measured by the concentration sensor 79: the concentration of the product gas in the raw material gas, the amount of heating performed by the heating device 20 to heat the separation membrane 1, and the pressure in the first space 31.

[0100] As described above, the product gas concentration adjustment mechanism 6 can control the concentration of the product gas in the raw material gas using the carrier gas supply control device 77, control the temperature of the separation membrane 1 using the heating device 20, and control the pressure of the first space 31 using the pressure control device 78, based on the concentration of the product gas measured by the concentration sensor 79.

[0101] The product gas concentration adjustment mechanism 6 may control at least one of the following based on the concentration of the product gas measured by the concentration sensor 79: the concentration of the product gas in the raw material gas, the temperature of the separation membrane 1, and the pressure of the first space 31. Of course, the product gas concentration adjustment mechanism 6 may simultaneously control two or all of the following: the concentration of the product gas in the raw material gas, the temperature of the separation membrane 1, and the pressure of the first space 31. [Examples]

[0102] The following describes the effects of the gas supply method according to this embodiment, based on the examples.

[0103] (Examples) An experiment to produce (supply) concentrated hydrazine gas using a gas supply device with the same configuration as the supply device 100 (see Figure 1) described in the above embodiment was conducted as an example (experiment number 1-10) as follows.

[0104] First, a liquid containing hydrazine (i.e., a solution, with diglycerin (diethylene glycol dimethyl ether) as the solvent) was sealed in a raw material container. Then, a carrier gas, as described later, was supplied to this raw material container, and 2% by volume of hydrazine gas (hydrazine vapor) was supplied from the raw material container to the first space of the gas separation container at 100 kPa (absolute pressure), and the concentrated gas was recovered from the second space. At this time, a separation membrane of the type described later was used. The separation membrane was also heated to the temperature described later.

[0105] The concentrated gas was recovered in a recovery container modeled after semiconductor manufacturing equipment. The pressure inside the recovery container was set to 1.33 kPa (absolute pressure). The concentration of hydrazine inside the recovery container was then measured. This hydrazine concentration was measured using an infrared absorption spectrometer (model VIR-200) manufactured by JASCO Corporation.

[0106] Steam experiments were conducted by varying the type of carrier gas and the temperature of the separation membrane. Nitrogen, hydrogen, and helium were used as carrier gases individually. The separation membrane temperatures were set to 50°C, 100°C, and 150°C. A zeolite membrane (Mitsubishi Chemical Corporation, CHA-type zeolite membrane, model number ZEBREX® ZX1) was used as the separation membrane.

[0107] Table 1 shows a summary of the experimental conditions and results (hydrazine concentration in concentrated gas). In Table 1, the column "Hydrazine Concentration (%)" refers to the hydrazine concentration (volume %) in the concentrated gas.

[0108] [Table 1]

[0109] As shown in Table 1, in all of the above examples (experiment numbers 1-10), concentrated gas containing hydrazine was successfully recovered into the recovery container.

[0110] (Comparative Examples 1 and 2) Next, the experiments for Comparative Examples 1 and 2 were conducted under the same conditions as experiments 4 and 7 in the above examples, except that the separation membrane was not heated and was kept at room temperature (25°C). However, hydrazine could not be detected in the recovery container.

[0111] For reference, after stopping the flow of the carrier gas, the concentration of hydrazine in the gas remaining in the first space of the gas separation container was measured, and no hydrazine was detected in this gas.

[0112] In Comparative Examples 1 and 2, unlike in the Examples, the separation membrane was not heated. Therefore, it is thought that approximately the entire amount of hydrazine supplied to the first space was adsorbed onto the separation membrane, making concentration impossible.

[0113] Considering the results of the above examples and comparative examples 1 and 2, it is thought that, in the case of the separation membranes used in the above examples and comparative examples 1 and 2, at temperatures above 25°C and below 100°C, specifically between 30°C and 70°C, the efficiency of hydrazine concentration increases as the temperature rises. In the range of 40°C to 150°C, although the rate at which hydrazine permeates through the separation membrane is thought to have reached its upper limit, the permeation of the carrier gas is also accelerated as the temperature rises, so it is thought that the concentration of hydrazine in the concentrated gas decreases. In other words, it is thought that the efficiency of hydrazine concentration is particularly high between 30°C and 150°C, and especially between 40°C and 120°C.

[0114] (Comparative Examples 3 and 4) Next, comparative examples 3 and 4 were conducted in the same manner as experiments 5 and 8 in the above examples, except that a silica membrane (manufactured by E-Sep, with a pore size of approximately 0.4 nm) was used as the separation membrane instead of the zeolite membrane. However, hydrazine could not be detected in the container of the recovery vessel.

[0115] For reference, similar to Comparative Examples 1 and 2, the concentration of hydrazine in the gas remaining in the first space of the gas separation container was measured after the flow of the carrier gas was stopped, but no hydrazine could be detected.

[0116] (Comparative Examples 5 and 6) Next, comparative examples 5 and 6 were conducted using a silica membrane (manufactured by E-Sep, with a pore size of approximately 0.4 nm) as the separation membrane instead of the zeolite membrane, and the separation membrane was not heated but kept at room temperature (25°C). The experiments were the same as those in experiments 4 and 7 of the above example. However, hydrazine could not be detected in the recovery container.

[0117] For reference, similar to Comparative Examples 1 and 2, the concentration of hydrazine in the gas remaining in the first space of the gas separation container was measured after the flow of the carrier gas was stopped, but no hydrazine could be detected.

[0118] In Comparative Examples 2 and 3, it is thought that the hydroxyl groups and methane groups contained in the silica film reacted with the hydrazine and became trapped (irreversibly adsorbed) by the silica film.

[0119] As described above, in Comparative Examples 1-6, the period during which concentrated product gas could be supplied stably was virtually zero.

[0120] As shown in the above examples and comparative examples, it can be seen that in the example according to the gas supply method of this embodiment, concentrated product gas can be supplied more stably than in the comparative example. In the comparative example, the period during which concentrated product gas could be supplied was substantially zero, so it can also be said that in the example, concentrated product gas can be supplied more stably for a longer period than in the comparative example.

[0121] As described above, a gas supply device and gas supply method can be provided that can stably supply concentrated gas, which is a concentrated product gas.

[0122] [Another embodiment] (1) In the above embodiment, the case in which the supply device 100 shown in Figure 1 is equipped with a product gas concentration adjustment mechanism 6 has been described, but the product gas concentration adjustment mechanism 6 is not an essential component of the supply device 100.

[0123] (2) In the above embodiment, the case described was one in which the concentration sensor 79 is installed in the concentrated gas supply pipe 74 of the supply device 100 shown in Figure 1 and measures the concentration of the product gas contained in the concentrated gas flowing through the concentrated gas supply pipe 74. However, the concentration sensor 79 may also measure the concentration of the product gas contained in the concentrated gas in the space of the second space section 32. In this case, the concentration sensor 79 can be installed in the gas separation container 2.

[0124] (3) In the above embodiment, the heating device 20 of the supply device 100 shown in Figure 1 is installed on the gas separation container 2, for example, so as to cover at least a part of the outer surface of the gas separation container 2, and the heating device 20 has been described as an example in which the separation membrane 1 is heated via the gas separation container 2. However, the heating device 20 may also be provided on the separation membrane 1, for example, to directly heat the separation membrane 1.

[0125] (4) In the above embodiment, the heating device 20 of the supply device 100 shown in Figure 1 was described as being installed on the gas separation container 2 so as to cover at least a part of the outer surface of the gas separation container 2. However, the heating device 20 may also heat the raw material gas supply pipe 72. In this case, the heating device 20 can heat the raw material gas flowing through the raw material gas supply pipe 72 and heat the separation membrane 1 with this raw material gas.

[0126] (5) In the above embodiment, as shown in Figure 2, the gas separation container 2 of the supply device 100 (see Figure 1) is formed in a cylindrical shape, and the separation membrane 1, which is formed in a flat plate shape, intersects (orthogonal in Figure 2) with the axial direction of the cylindrical gas separation container 2, and the internal space of the gas separation container 2 is divided into a first space 31 located on one side in the axial direction of the gas separation container 2 and a second space 32 located on the other side in the axial direction of the gas separation container 2. However, the shape and arrangement of the gas separation container 2 and the separation membrane 1 are not limited to the above example.

[0127] As shown in Figure 3, the separation membrane 1 may be formed in a cylindrical shape. This cylindrical separation membrane 1 may be housed in the internal space of the gas separation container 2 with its axis aligned with the axial direction of the gas separation container 2. That is, the separation membrane 1 may be housed in the gas separation container 2 in a double-tube shape. In the gas separation container 2 illustrated in Figure 3, the separation membrane 1 divides the internal space of the gas separation container 2 into a first space 31 located on the outer side of the cylindrical separation membrane 1 in the radial direction and a second space 32 located on the inner side of the cylindrical separation membrane 1 in the radial direction.

[0128] (6) In the above embodiment, the case in which the supply device 100 shown in Figure 1 is equipped with a raw material container 70 and a carrier gas supply control device 77 has been described, but the raw material container 70 and the carrier gas supply control device 77 are not essential components of the supply device 100.

[0129] (7) In the above embodiment, the case in which the supply device 100 shown in Figure 1 is equipped with a temperature sensor 29 was described, but the temperature sensor 29 is not an essential component of the supply device 100.

[0130] (8) In the above embodiment, the case in which the supply device 100 shown in Figure 1 is equipped with a pressure control device 78 was described, but the temperature sensor 29 is not an essential component of the supply device 100.

[0131] Furthermore, the configurations disclosed in the above embodiments (including other embodiments, the same applies hereinafter) can be applied in combination with configurations disclosed in other embodiments, as long as no inconsistencies arise. In addition, the embodiments disclosed herein are illustrative, and the embodiments of the present invention are not limited thereto, and can be modified as appropriate without departing from the object of the present invention. [Industrial applicability]

[0132] The present invention can be applied to gas supply devices and gas supply methods. [Explanation of Symbols]

[0133] 1: Separation membrane 100: Feeding device 2: Gas separation vessel 20: Heating device 29: Temperature sensor 31:First space part 32:Second space part 41: Raw material gas inlet 42: Outlet 43: Exhaust vent 45: Sweep gas inlet 6: Product gas concentration adjustment mechanism 70: Raw material container 70a: Carrier gas inlet 70b: Raw material delivery port 71: Carrier gas piping 72: Raw material gas supply pipe 73: Exhaust gas pipes 74: Concentrated gas supply pipe 75: Sweep gas supply pipe 77: Carrier gas supply control device 78: Pressure control device 79: Concentration sensor 9: Semiconductor manufacturing equipment G1: Gas G2: Gas G3: Gas G4: Gas G5: Gas

Claims

1. A gas separation membrane that permeates the product gas, A gas separation container containing the separation membrane, The system includes a heating device for heating the separation membrane, The aforementioned gas separation container is A first space for storing the gas containing the aforementioned product gas as a raw material gas, The first space and the second space separated by the separation membrane, A raw material gas inlet that communicates with the first space and introduces the raw material gas into the first space, A gas supply device having an outlet that communicates with the second space and discharges concentrated gas, which is obtained by concentrating the product gas from the second space.

2. The gas supply device according to claim 1, wherein the product gas comprises hydrazine or hydrogen peroxide.

3. The gas supply device according to claim 1, wherein the separation membrane comprises at least one of a zeolite membrane and an organometallic structure membrane.

4. The system further includes a temperature sensor for measuring the temperature of the separation membrane, The gas supply device according to claim 1, wherein the heating device controls the amount of heating to heat the separation membrane based on the temperature of the separation membrane measured by the temperature sensor.

5. The gas supply device according to claim 4, wherein the heating device heats the separation membrane so that the temperature of the separation membrane is 30°C or more and 150°C or less.

6. The gas supply device according to any one of claims 1 to 5, further comprising a concentration sensor for measuring the concentration of the product gas in the concentrated gas.

7. The gas supply device according to claim 6, wherein the heating device controls the amount of heating for heating the separation membrane based on the concentration of the product gas in the concentrated gas measured by the concentration sensor.

8. The system further comprises a raw material container for storing the materials of the product gas and supplying the raw material gas to the gas separation container, The aforementioned raw material container is A carrier inlet to which carrier gas is supplied, The gas supply device according to claim 6, further comprising a raw material outlet for supplying a mixed gas of the carrier gas and the product gas to the gas separation container as the raw material gas.

9. The system further includes a carrier gas supply control device that controls the amount of carrier gas supplied to the carrier inlet, The gas supply device according to claim 8, wherein the carrier gas supply control device controls the amount of carrier gas supplied based on the concentration of the product gas in the concentrated gas measured by the concentration sensor.

10. The system further includes a pressure control device for adjusting the pressure in the first space, The gas supply device according to claim 6, wherein the pressure control device controls the pressure in the first space based on the concentration of the product gas measured by the concentration sensor.

11. The system further includes a product gas concentration adjustment mechanism for controlling the concentration of the product gas in the concentrated gas, The gas supply device according to claim 6, wherein the product gas concentration adjustment mechanism controls at least one of the product gas concentration in the raw material gas, the temperature of the separation membrane, and the pressure of the first space based on the concentration of the product gas measured by the concentration sensor.

12. A concentration step in which a gas containing the product gas is brought into contact with a separation membrane as a raw material gas, the product gas is concentrated from the raw material gas by permeating through the separation membrane, and the concentrated gas containing the product gas is discharged. The heating step includes heating the separation membrane, The heating step is a gas supply method performed during the concentration step.

13. The gas supply method according to claim 12, wherein the product gas is hydrazine or hydrogen peroxide.

14. The gas supply method according to claim 12, wherein at least one of a zeolite membrane and an organometallic structure membrane is used as the separation membrane.

15. The gas supply method according to claim 12, wherein the heating step controls the amount of heating to heat the separation membrane based on the temperature of the separation membrane.

16. The gas supply method according to claim 15, wherein the heating step involves heating the separation membrane so that the temperature of the separation membrane is 30°C or higher and 150°C or lower.

17. The gas supply method according to any one of claims 12 to 16, wherein the amount of heating used to heat the separation membrane is controlled based on the concentration of the product gas in the concentrated gas.

18. The process further includes a mixing step in which a mixed gas obtained by mixing a carrier gas and the product gas is used as the raw material gas, The gas supply method according to any one of claims 12 to 16, wherein in the mixing step, the concentration of the product gas in the raw material gas is controlled based on the concentration of the product gas in the concentrated gas.

19. The gas supply method according to any one of claims 12 to 16, wherein in the concentration step, the pressure of the raw material gas in contact with the separation membrane is controlled based on the concentration of the product gas in the concentrated gas.

20. A gas supply method according to any one of claims 12 to 16, wherein at least one of the following is controlled based on the concentration of the product gas in the concentrated gas: the concentration of the product gas in the raw material gas, the temperature of the separation membrane, and the pressure of the raw material gas in contact with the separation membrane.

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