Production method and transfer method for carbon monoxide gas

Abstract

The present disclosure relates to a production method for carbon monoxide gas which includes a transfer step in which carbon monoxide gas is transferred from a first vessel to a second vessel through a metal pipeline. In the transfer step, when the flow rate of the carbon monoxide gas per unit area in the metal pipeline is expressed by A (NL / min / m2), the carbon monoxide gas is transferred so that the common logarithm of A, logA, is -1 to 5. The metal pipeline has a length of 0.5-100 m and an inner diameter of 0.5-30 mm.

Description

Carbon monoxide gas production and transport method

[0001] The present disclosure relates to methods for producing and transporting carbon monoxide gas.

[0002] Carbon monoxide gas is used in various industries, such as semiconductor manufacturing processes and metal refining, and in recent years, the demand for carbon monoxide gas has been increasing, particularly in semiconductor manufacturing processes (e.g., etching processes). When carbon monoxide gas is used, it is generally transferred from a container containing the carbon monoxide gas to a destination container through metal piping.

[0003] Carbon monoxide gas is highly reactive with metals and reacts with them to form metal carbonyls. These metal carbonyls are impurities in carbon monoxide gas used in semiconductor manufacturing processes and may contaminate devices obtained through such processes, causing malfunctions. Therefore, it is desirable for the content of metal carbonyls in carbon monoxide gas to be as low as possible.

[0004] For example, in Patent Document 1, in order to reduce the content of metal carbonyl in carbon monoxide gas, carbon monoxide is sealed in a sealed container containing a stainless steel regulating valve, and a CO exposure treatment is performed in which the stainless steel regulating valve is exposed to carbon monoxide gas, and Ni deposited on the surface of the stainless steel regulating valve reacts with CO to produce Ni(CO). ４ and supplying carbon monoxide to a CO-consuming facility using a piping system that uses a stainless steel regulating valve that has been CO-exposed.

[0005] Japanese Patent Application Laid-Open No. 2005-265116

[0006] Incidentally, it is desirable that the content of metal carbonyls in carbon monoxide gas be 0.1 mol ppb or less, which is close to the detection limit. However, even when using a piping system with a stainless steel regulating valve that has been CO exposed according to the method described in Patent Document 1, it was difficult to maintain the content of metal carbonyls in carbon monoxide gas at 0.1 mol ppb or less. Furthermore, the method requires CO exposure treatment of the stainless steel regulating valve, which is time-consuming. Furthermore, the method leaves room for improvement in terms of miniaturization of the equipment used to implement the method.

[0007] Therefore, an object of the present disclosure is to provide a method for transferring carbon monoxide gas, which allows for easy transfer of carbon monoxide gas without significantly increasing the metal carbonyl content and which enables the equipment to be downsized, and a method for producing carbon monoxide gas, which allows the produced carbon monoxide gas to be provided to the next step without significantly increasing the metal carbonyl content and which enables the equipment to be downsized.

[0008] The present disclosure provides the following carbon monoxide gas production methods and transfer methods [1] to

[20] . [1] A carbon monoxide gas production method including a transfer step of transferring carbon monoxide gas from a first container to a second container through a metal pipe, wherein in the transfer step, the flow rate per unit area of ​​the carbon monoxide gas in the metal pipe is controlled to A (NL / min / m ２) the carbon monoxide gas is transferred so that the common logarithm of A, log A, is -1 to 5, and the metal piping has a length of 0.5 to 100 m and an inner diameter of 0.5 to 30 mm. [2] The method according to [1], wherein the temperature of the metal piping is set to 40°C or less in the transferring step. [3] The method according to [1] or [2], wherein the content of metal carbonyl in the carbon monoxide gas in the first vessel is less than 0.05 mol ppb. [4] The method according to [3], wherein the metal carbonyl is at least one selected from the group consisting of Ni—CO and Fe—CO. [5] The method according to any one of [1] to [4], wherein the metal piping comprises stainless steel. [6] The method according to any one of [1] to [5], wherein the purity of the carbon monoxide gas in the first vessel is 99.99 mol % or more. [7] The method according to any one of [1] to [6], wherein in the transferring step, carbon monoxide gas supplied from a gas supply facility is compressed by a compressor and then transferred from a first container to a second container through a metal pipe. [8] The method according to any one of [1] to [7], wherein the first container has a container for storing carbon monoxide gas, the container being made of metal, and the metal including stainless steel. [9] The method according to any one of [1] to [8], wherein the second container has a container for storing carbon monoxide gas, the container being made of metal, and the metal including manganese steel or an aluminum alloy.

[10] The method according to any one of [1] to [9], wherein the second container is a reaction chamber of a semiconductor manufacturing device.

[11] A method for transferring carbon monoxide gas, comprising a transferring step of transferring carbon monoxide gas from a first container to a second container through a metal pipe, wherein in the transferring step, a flow rate per unit area of ​​the carbon monoxide gas in the metal pipe is set to A (NL / min / m ２) the carbon monoxide gas is transferred so that the common logarithm of A, log A, is -1 to 5, and the metal piping has a length of 0.5 to 100 m and an inner diameter of 0.5 to 30 mm.

[12] The method according to

[11] , wherein the temperature of the metal piping is set to 40°C or less in the transferring step.

[13] The method according to

[11] or

[12] , wherein the content of metal carbonyl in the carbon monoxide gas in the first vessel is less than 0.05 mol ppb.

[14] The method according to

[13] , wherein the metal carbonyl is at least one selected from the group consisting of Ni—CO and Fe—CO.

[15] The method according to any one of

[11] to

[14] , wherein the metal piping comprises stainless steel.

[16] The method according to any one of

[11] to

[15] , wherein the purity of the carbon monoxide gas in the first vessel is 99.99 mol % or more.

[17] The method according to any one of

[11] to

[16] , wherein in the transferring step, carbon monoxide gas supplied from a gas supply facility is compressed by a compressor and then transferred from the first container to the second container through a metal pipe.

[18] The method according to any one of

[11] to

[17] , wherein the first container has a container for storing carbon monoxide gas, the container being made of metal, and the metal including stainless steel.

[19] The method according to any one of

[11] to

[18] , wherein the second container has a container for storing carbon monoxide gas, the container being made of metal, and the metal including manganese steel or an aluminum alloy.

[20] The method according to any one of

[11] to

[19] , wherein the second container is a reaction chamber of a semiconductor manufacturing device.

[0009] According to the present disclosure, there are provided a method for transporting carbon monoxide gas, which allows for easy transport of carbon monoxide gas without significantly increasing the metal carbonyl content and which enables the equipment to be downsized, and a method for producing carbon monoxide gas, which allows the produced carbon monoxide gas to be provided to the next step without significantly increasing the metal carbonyl content and which enables the equipment to be downsized.

[0010] 1 is a schematic diagram showing an example of equipment for carrying out the carbon monoxide gas production method of the present disclosure.

[0011] Hereinafter, embodiments of the carbon monoxide gas production method and transfer method of the present disclosure will be described in detail with reference to Fig. 1. Fig. 1 is a schematic diagram showing an example of a carbon monoxide gas production apparatus that implements the carbon monoxide gas production method of the present disclosure. Note that the present disclosure is not limited to the following embodiment.

[0012] The carbon monoxide gas production method of the present disclosure can be carried out, for example, by a carbon monoxide gas production facility 100 shown in Fig. 1. The carbon monoxide gas production facility 100 includes a first container 10, a second container 30, and metal piping 20 connecting the first container 10 and the second container 30. The production facility 100 may further include a compressor 40 connected to the first container 10, and a gas supply facility or gas container (hereinafter referred to as "gas supply facility") 60 for supplying carbon monoxide gas to the compressor 40. The production facility 100 may further include a flow meter 50 installed in the metal piping 20.

[0013] Furthermore, if a large amount of metal carbonyl is generated due to the reaction of the material in the gas-contacting part of compressor 40 with carbon monoxide gas, accompanied by the heat of compression, a tower (not shown) packed with an adsorbent capable of adsorbing and removing metal carbonyl or a catalyst capable of decomposing metal carbonyl may be further installed between compressor 40 and second vessel 30.

[0014] The carbon monoxide gas manufacturing method and transfer method disclosed herein include a transfer step of transferring carbon monoxide gas from a first container 10 to a second container 30 through a metal pipe 20. In the manufacturing facility 100 shown in FIG. 1 , carbon monoxide gas compressed by a compressor 40 is transferred from the first container 10 to the second container 30 through the metal pipe 20. In the transfer step, the flow rate per unit area of ​​the carbon monoxide gas in the metal pipe 20 is set to A (NL / min / m ２ ), carbon monoxide gas is transferred so that the common logarithm of A, log A, is −1 to 5. Here, the length of the metal pipe 20 is 0.5 to 100 m, and the inner diameter is 0.5 to 30 mm.

[0015] According to the carbon monoxide gas production method and transfer method disclosed herein, in the transfer step, carbon monoxide gas is transferred so that the flow rate per unit area of ​​the carbon monoxide gas within the metal pipe 20, which has a length of 0.5 to 100 m and an inner diameter of 0.5 to 30 mm, does not become too low, eliminating the need to seal the carbon monoxide gas within the metal pipe 20 and expose the metal pipe 20 to the carbon monoxide gas, and carbon monoxide gas with a reduced metal carbonyl content can be easily transferred simply by adjusting the flow rate per unit area and the length and inner diameter of the metal pipe 20. Furthermore, in the transfer step, carbon monoxide gas is transferred at a relatively low flow rate per unit area within the metal pipe 20, allowing for a reduction in the size of the compressor 40 that compresses carbon monoxide supplied from the gas supply facility 60 and supplies it to the first container 10, and ultimately allowing for a reduction in the size of the carbon monoxide gas production facility 100. Therefore, according to the method for producing or transferring carbon monoxide gas disclosed herein, carbon monoxide gas can be easily produced or transferred without significantly increasing the metal carbonyl content, and the production facility 100 can be made smaller. In the method for producing or transferring carbon monoxide gas disclosed herein, the flow rate per unit area of ​​carbon monoxide gas in the metal piping during the transfer step is set to A (NL / min / m ２ ), the common logarithm logA of A is preferably −0.5 to 4, more preferably 1 to 3.5, and particularly preferably 2.5 to 3.2.

[0016] In the above-described transfer step, it is preferable to transfer the carbon monoxide gas so that the amount of metal carbonyl discharged from the metal pipe 20 is 0.1 mol ppb or less in the carbon monoxide gas. Metal carbonyl is an impurity in the carbon monoxide gas used in semiconductor manufacturing processes, etc. Therefore, by reducing the metal carbonyl content, contamination of devices obtained in device manufacturing equipment to which carbon monoxide gas is supplied can be suppressed, and functional failure of the devices can be suppressed.

[0017] The first vessel 10, the metal pipe 20, the second vessel 30, the compressor 40, the flow meter 50, the gas supply facility 60, and the transfer process will be described in detail below.

[0018] (First Container) The first container 10 is not particularly limited as long as it is a container capable of supplying carbon monoxide gas. The first container 10 has a container for storing carbon monoxide gas. For example, a metal container is used as the container. Examples of metals that constitute the metal container include stainless steel, manganese steel, aluminum alloys, and Ni alloys, with stainless steel being preferred. In this case, the first container 10 is less likely to react with carbon monoxide, less likely to generate metal carbonyl, and has excellent pressure resistance.

[0019] Although there are no particular limitations on the metal carbonyl content in the carbon monoxide gas in first container 10, it is preferable that it be less than 0.05 mol ppb. In this case, even if the flow rate per unit area of ​​carbon monoxide gas is reduced, the metal carbonyl content in the carbon monoxide gas that has passed through metal pipe 20 can be more easily reduced to 0.1 mol ppb or less, which allows compressor 40 to be made more compact, and ultimately allows the equipment 100 for producing carbon monoxide gas to be made more compact.

[0020] The content of metal carbonyl in the carbon monoxide gas in the first container 10 is more preferably 0.01 mol ppb or less, and particularly preferably 0.001 mol ppb or less. The content of metal carbonyl in the carbon monoxide gas in the first container 10 may be 0.0001 mol ppb or more, or 0.0005 mol ppb or more.

[0021] The purity of the carbon monoxide gas in the first container 10 may be 99 mol% or more, 99.9 mol% or more, or 99.99 mol% or more, but is preferably 99.99 mol% or more. In this case, highly pure carbon monoxide gas can be obtained in the second container 30. The purity of the carbon monoxide gas in the first container 10 may be 99.99999 mol%.

[0022] (Metal Piping) Examples of metals constituting the metal pipe 20 include stainless steel, aluminum alloys, and Ni alloys. Of these, stainless steel is preferred. In this case, even if the flow rate per unit area of ​​carbon monoxide gas is reduced, the amount of metal carbonyl discharged from the metal pipe 20 can be more easily reduced to 0.1 mol ppb or less, which allows the compressor 40 to be made more compact, and ultimately the facility 100 for producing carbon monoxide gas to be made more compact.

[0023] The length of the metal pipe 20 is 0.5 to 100 m. If the metal pipe 20 is too short, the metal pipe 20 is unsuitable for the configuration of the manufacturing equipment 100, whereas if the metal pipe 20 is too long, the contact area between the metal pipe 20 and the carbon monoxide gas increases, increasing the required CO ventilation flow rate, which is undesirable from the perspective of miniaturizing the manufacturing equipment 100. The length of the metal pipe 20 is preferably 0.75 to 90 m, more preferably 1 to 75 m, and particularly preferably 2 to 50 m.

[0024] The inner diameter of the metal pipe 20 is 0.5 to 30 mm. If the inner diameter of the metal pipe 20 is too small, the pressure loss increases and carbon monoxide does not flow, whereas if the inner diameter of the metal pipe 20 is too large, the contact area between the carbon monoxide and the metal pipe 20 increases, making it difficult to keep the metal carbonyl content at 0.1 mol ppb or less. The inner diameter of the metal pipe 20 is preferably 0.57 mm to 22.1 mm, more preferably 1.4 mm to 10.92 mm, and particularly preferably 3.05 mm to 7.75 mm.

[0025] The area of ​​the inner surface of the metal pipe 20 is determined by the inner diameter (the diameter obtained by subtracting the wall thickness of the pipe from the outer diameter) and the length of the metal pipe 20, but is preferably 0.002 to 9 m ２ When there are multiple second containers 30, the manufacturing facility 100 may further include at least one branch pipe branching off from the middle of the metal pipe 20. In this case, by connecting a second container 30 to the tip of at least one branch pipe, it is possible to increase the number of destinations for the carbon monoxide gas.

[0026] The flow rate A per unit area of ​​carbon monoxide gas in the metal pipe 20 is calculated by converting the flow rate measured by the flow meter 50 into a value under standard conditions and calculating the contact area (m ２ ) where the contact area (m ２ ) specifically refers to the area of ​​the inner surface of the metal pipe 20. The "unit area" in the "flow rate A of carbon monoxide gas per unit area" refers to the unit area of ​​the surface area within the metal pipe 20.

[0027] A is calculated as follows: The flow rate of metal carbonyl generated while carbon monoxide gas is transferred through the metal pipe 20 is defined as B (NL / min / m ２ ), and the amount of metal carbonyl discharged from the metal pipe 20 is 0.1 (mol ppb) in carbon monoxide gas, 1 mol ppb = 1 × 10 －９ Therefore, the following equation holds: B / (A+B)=0.1×10 －９ ... (1) From the above formula (1), A is expressed by the following formula (2): A = B / (0.1 × 10 －９ ) -B ... (2)

[0028] Here, B is the carbon monoxide gas contact area S (m ２ ), it can be experimentally determined from the concentration C (mol ppb) of metal carbonyl generated when the carbon monoxide gas contact area S (m ２ ) refers to the area of ​​the inner surface of the metal pipe.

[0029] Specifically, first, the amount of metal carbonyl generated per unit time and unit area (metal carbonyl generation rate) M (mol / h / m) is calculated from the following equation (3): ２The metal carbonyl generation concentration C can be determined by sampling the carbon monoxide gas filled in the metal pipe and analyzing the metal carbonyl (M-CO, where "M" represents a metal atom) in the carbon monoxide gas using ICP-MS (inductively coupled plasma mass spectrometry). The metal carbonyl generation rate M (mol / h / m ２ ) = piping volume V (L) × filling pressure P (MPaG) × 10 × metal carbonyl generation concentration C (mol ppb) × 10 －９ ÷ 22.4 NL / mol ÷ carbon monoxide gas contact area S (m ２ ) ÷ Standing time t (h) ... (3)

[0030] Next, B can be calculated from the M calculated as above and the following formula (4): B (NL / min / m ２ )=M(mol / h / m ２ )÷60(min / h)×22.4(NL / mol) =0.37M...(4)

[0031] Here, a method for determining the flow rate A per unit area of ​​carbon monoxide gas in the metal pipe 20 will be specifically described using Experimental Examples 1 to 4.

[0032] (Experimental Example 1) A BA (Bright Annealing) pipe made of SUS316L, with an inner diameter of 4.57 mm (wall thickness of 0.89 mm) and a length of 65 cm, was filled with carbon monoxide gas (Ni—CO concentration: less than 0.05 mol ppb) to a filling pressure of 9.0 MPaG at room temperature (25°C) (the amount of carbon monoxide gas filled was 0.96 L converted to atmospheric pressure). After filling, the pipe was left to stand in a space set at room temperature (25°C) for approximately 119 hours. Thereafter, the entire amount of filled carbon monoxide gas was sampled, and the metal carbonyl (M—CO) in the carbon monoxide gas was analyzed by ICP-MS (inductively coupled plasma mass spectrometry). As a result, the Ni—CO generation concentration C in the carbon monoxide gas was 2.8 mol ppb. Next, the metal carbonyl generation concentration C (mol ppb), the piping volume V (L), the filling pressure P (MPaG), and the carbon monoxide gas contact area S (m ２), the standing time t (h), and the above formula (3) were used to calculate the amount of Ni—CO generated per unit time per unit area (Ni—CO generation rate) M, and the Ni—CO generation rate M was found to be 1.1 × 10 －１０ mol / h / m ２ From this value of the generation rate M of Ni-CO and the above formula (4), the generation flow rate B of Ni-CO was 4.1 × 10 －１１ NL / min / m ２ Then, using the value of B calculated as described above and the above formula (2), the flow rate A of carbon monoxide gas per unit area required to make the Ni-CO concentration during transfer 0.1 mol ppb was calculated, and the common logarithm value log A was -0.4. The results are shown in Table 1.

[0033] (Experimental Example 2) Carbon monoxide gas (Ni-CO concentration: less than 0.05 mol ppb) was filled into a BA pipe made of SUS316L with an inner diameter of 4.57 mm (wall thickness of 0.89 mm) and a length of 65 cm, so that the filling pressure at 40°C was 9.0 MPaG (the amount of carbon monoxide gas filled was 0.91 L converted to atmospheric pressure). After filling, the pipe was heated to 40°C and allowed to stand for approximately 88 hours. Thereafter, the entire amount of filled carbon monoxide gas was sampled, and the metal carbonyl (M-CO) in the carbon monoxide gas was analyzed by ICP-MS (inductively coupled plasma mass spectrometry). As a result, the Ni-CO generation concentration C in the carbon monoxide gas was 2.1 mol ppb. Next, the metal carbonyl generation concentration C (mol ppb) was calculated in relation to the pipe volume V (L), the filling pressure P (MPaG), and the carbon monoxide gas contact area S (m ２ ), the standing time t (h), and the above formula (3) were used to calculate the amount of Ni—CO generated per unit time per unit area (Ni—CO generation rate) M, and the Ni—CO generation rate M was found to be 1.0 × 10 －１０ mol / h / m ２ From this value of the generation rate M of Ni-CO and the above formula (4), the generation flow rate B of Ni-CO was 3.8 × 10 －１１ NL / min / m ２Then, using the value of B calculated as described above and the above formula (2), the CO flow rate A per unit area required for the Ni-CO concentration during transfer to reach 0.1 mol ppb was calculated, and the common logarithm value log A was -0.4. The results are shown in Table 1.

[0034] (Experimental Example 3) Carbon monoxide gas (Ni—CO concentration: less than 0.05 mol ppb) was filled into a BA pipe made of SUS316L with an inner diameter of 4.57 mm (wall thickness of 0.89 mm) and a length of 65 cm, so that the filling pressure at 75°C was 9.0 MPaG (the amount of carbon monoxide gas filled was 0.82 L converted to atmospheric pressure). After filling, the pipe was heated to 75°C and allowed to stand for about 46 hours. Thereafter, the entire amount of filled carbon monoxide gas was sampled, and the metal carbonyl (M—CO) in the carbon monoxide gas was analyzed by ICP-MS (inductively coupled plasma mass spectrometry). As a result, the Ni—CO generation concentration C in the carbon monoxide gas was 91.9 mol ppb. Next, the metal carbonyl generation concentration C (mol ppb) was calculated in relation to the pipe volume V (L), the filling pressure P (MPaG), and the carbon monoxide gas contact area S (m ２ ), the standing time t (h), and the above formula (3) were used to calculate the amount of Ni—CO generated per unit time per unit area (Ni—CO generation rate) M, which was found to be 7.8×10 －９ mol / h / m ２ From this value of the generation rate M of Ni-CO and the above formula (4), the generation flow rate B of Ni-CO was 2.9 × 10 -9 NL / min / m ２ Then, using the value of B calculated as described above and the above formula (2), the CO flow rate A per unit area required for the Ni-CO concentration during transfer to reach 0.1 mol ppb was calculated, and the common logarithm value log A was 1.5. The results are shown in Table 1.

[0035] (Experimental Example 4) A pipe made of SUS316L with an inner diameter of 4.57 mm (wall thickness of 0.89 mm) and a length of 1272 cm was connected to a pipe made of SUS304 with an inner diameter of 29.9 mm (wall thickness of 6.4 mm) and a length of 107 cm. Carbon monoxide gas was filled into the pipe so that the filling pressure at 30°C was 16.5 MPaG. After filling, the pipe was left to stand at 30°C for approximately 17 hours. Thereafter, the filled carbon monoxide gas was sampled and analyzed for metal carbonyl (M-CO) in the carbon monoxide gas by ICP-MS (inductively coupled plasma mass spectrometry). As a result, the Ni-CO generation concentration C in the carbon monoxide gas was 114.3 mol ppb. Next, the metal carbonyl generation concentration C (mol ppb) was calculated in relation to the pipe volume V (L), the filling pressure P (MPaG), and the carbon monoxide gas contact area S (m ２ ), the standing time t (h), and the above formula (3), the amount of Ni—CO generated per unit time per unit area (Ni—CO generation rate) M was calculated, and the Ni—CO generation rate M was found to be 2.3 × 10 －７ mol / h / m ２ From this value of the generation rate M of Ni-CO and the above formula (4), the generation flow rate B of Ni-CO was 8.5 × 10 -８ NL / min / m ２ Then, using the value of B calculated as described above and the above formula (2), the CO flow rate A per unit area required for the Ni-CO concentration during transfer to reach 0.1 mol ppb was calculated, and the common logarithm value log A was 2.9. The results are shown in Table 1.

[0036]

[0037] The metal carbonyl is not particularly limited, and examples of the metal carbonyl include Ni—CO and Fe—CO. These may be composed of either a single compound or a mixture of two or more compounds. The metal carbonyl content refers to the amount determined by sampling the carbon monoxide gas discharged from the metal pipe 20 and analyzing the metal carbonyl (M-CO) in the carbon monoxide gas by ICP-MS (inductively coupled plasma mass spectrometry).

[0038] The temperature of the metal pipe 20 is not particularly limited and may be 70°C or less, 60°C or less, 50°C or less, 40°C or less, or 30°C or less, but is preferably 40°C or less. In this case, even if the flow rate per unit area of ​​carbon monoxide gas is reduced, the amount of metal carbonyl discharged from the metal pipe 20 can be kept to 0.1 mol ppb or less in the carbon monoxide gas, which allows the compressor 40 to be made more compact, and ultimately the manufacturing equipment 100 to be made more compact. The temperature of the metal pipe 20 may be 0°C or more, 10°C or more, or 20°C or more.

[0039] The pressure of the gas inside the metal pipe 20 is not particularly limited, but from a safety standpoint, it is preferable that the pressure be within the range of pressure resistance considering the diameter and thickness of the metal pipe 20. For example, if the metal pipe 20 is a half-inch pipe (thickness 1.24 mm), the maximum pressure will be approximately 20 MPaG. On the other hand, the filling pressure of a high-purity carbon monoxide product varies depending on customer requests, but is usually 4 to 15 MPa, and within this pressure range, there is no significant difference in the amount of metal carbonyl generated.

[0040] (Compressor) The compressor 40 may be any device that compresses carbon monoxide gas, and examples of the compressor 40 include a centrifugal compressor, an axial compressor, and a diaphragm compressor.

[0041] (Flow Meter) The flow meter 50 is a device that measures the flow rate of carbon monoxide gas in the metal pipe 20. The position of the flow meter 50 is not particularly limited as long as it is located on the metal pipe 20.

[0042] (Second Container) The second container 30 is a container included in an apparatus that requires carbon monoxide gas. As with the first container 10, this container may be, for example, a metal container. Examples of metals included in the metal container include manganese steel and aluminum alloy. The second container 30 may be, for example, a reaction chamber of a semiconductor manufacturing apparatus.

[0043] (Gas Supply Equipment) The gas supply equipment 60 is not particularly limited as long as it can supply carbon monoxide gas. The gas supply equipment 60 may be a gas container that temporarily stores generated or purified carbon monoxide gas, or may be the equipment itself that generates or purifies carbon monoxide gas. Known methods for generating carbon monoxide gas include a method of obtaining carbon monoxide gas by steam reforming natural gas, a method of obtaining carbon monoxide gas by contacting light hydrocarbons with oxygen in the presence of a partial oxidation catalyst, and a method of obtaining carbon monoxide gas by decomposing formic acid. Further known methods for obtaining carbon monoxide gas by decomposing formic acid include a method using a mineral acid and a method using a solid acid catalyst. Known methods for purifying carbon monoxide gas include a method of cooling carbon monoxide gas to remove moisture from the carbon monoxide gas, a method of washing carbon monoxide gas with an aqueous alkali solution, a method of washing carbon monoxide gas with water, a method of drying carbon monoxide gas using a desiccant, a method of removing impurities from carbon monoxide gas using an adsorbent such as activated carbon, and a method of combining two or all of these methods, and these methods can also produce carbon monoxide gas having a metal carbonyl content of less than 0.05 mol ppb.

[0044] 10...first vessel, 20...metal piping, 30...second vessel, 40...compressor, 50...flow meter, 60...gas supply equipment, 100...carbon monoxide gas production equipment.

Claims

1. A method for producing carbon monoxide gas, comprising a transfer step of transferring carbon monoxide gas from a first container to a second container through a metal pipe, wherein in the transfer step, the flow rate per unit area of ​​the carbon monoxide gas in the metal pipe is controlled to A (NL / min / m ２ ), the carbon monoxide gas is transferred so that the common logarithm of A, log A, is in the range of −1 to 5, and the metal pipe has a length of 0.5 to 100 m and an inner diameter of 0.5 to 30 mm.

2. The method according to claim 1, wherein the temperature of the metal pipe is kept at 40°C or less in the transferring step.

3. The method of claim 1 or 2, wherein the carbon monoxide gas in the first vessel contains less than 0.05 mole ppb of metal carbonyls.

4. The method according to claim 3, wherein the metal carbonyl is at least one selected from the group consisting of Ni-CO and Fe-CO.

5. The method of claim 1 or 2, wherein the metal piping comprises stainless steel.

6. The method of claim 1 or 2, wherein the purity of the carbon monoxide gas in the first vessel is 99.99 mole percent or greater.

7. The method according to claim 1 or 2, wherein in the transferring step, carbon monoxide gas supplied from a gas supply facility is compressed by a compressor and then transferred from the first container to the second container through a metal pipe.

8. The method of claim 1 or 2, wherein the first container comprises a container containing carbon monoxide gas, the container being constructed from a metal, and the metal comprising stainless steel.

9. The method of claim 1 or 2, wherein the second container comprises a container containing carbon monoxide gas, the container being constructed of a metal, and the metal comprising manganese steel or an aluminum alloy.

10. The method of claim 1 or 2, wherein the second vessel is a reaction chamber of a semiconductor manufacturing device.

11. A method for transferring carbon monoxide gas, comprising a transfer step of transferring carbon monoxide gas from a first container to a second container through a metal pipe, wherein in the transfer step, the flow rate per unit area of ​​the carbon monoxide gas in the metal pipe is controlled to A (NL / min / m ２ ), the carbon monoxide gas is transferred so that the common logarithm of A, log A, is -1 to 5, and the metal pipe has a length of 0.5 to 100 m and an inner diameter of 0.5 to 30 mm.

12. The method according to claim 11, wherein the temperature of the metal pipe is set to 40°C or less in the transferring step.

13. The method of claim 11 or 12, wherein the carbon monoxide gas in the first vessel contains less than 0.05 mole ppb of metal carbonyls.

14. The method according to claim 13, wherein the metal carbonyl is at least one selected from the group consisting of Ni-CO and Fe-CO.

15. The method of claim 11 or 12, wherein the metal piping comprises stainless steel.

16. The method of claim 11 or 12, wherein the purity of the carbon monoxide gas in the first vessel is 99.99 mole percent or greater.

17. The method according to claim 11 or 12, wherein in the transferring step, carbon monoxide gas supplied from a gas supply facility is compressed by a compressor and then transferred from the first container to the second container through a metal pipe.

18. The method of claim 11 or 12, wherein the first container comprises a container containing carbon monoxide gas, the container being constructed from a metal, and the metal comprising stainless steel.

19. The method of claim 11 or 12, wherein the second container comprises a container containing carbon monoxide gas, the container being constructed of a metal, and the metal comprising manganese steel or an aluminum alloy.

20. The method of claim 11 or 12, wherein the second vessel is a reaction chamber of a semiconductor manufacturing device.

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