Method for measuring fluorine gas concentration in halogen-containing fluoride gas by mass spectrometer

Abstract

The object of the present invention is to provide a high-precision measurement method, which reduces the measurement error of fluorine gas concentration caused by the consumption of metal components and impurities on the gas flow path reacting with fluorine gas when measuring the fluorine gas concentration contained in halogen-containing fluoride gas using a mass spectrometer. The present invention includes a method for measuring fluorine gas concentration, which is a method for measuring the concentration of fluorine gas (F2) contained in halogen-containing fluoride gas using an analysis device (10) having a halogen-containing fluoride gas supply source (16), a fluorine-containing gas supply source (14), a piping (24), a capillary (28) and a mass spectrometer (30), characterized in that before measuring the fluorine gas concentration, the piping and the capillary are passivated using a passivation gas containing the fluorine-containing gas supplied from the fluorine-containing gas supply source.

Description

Technical Field

[0001] The present invention relates to a method for measuring the fluorine gas concentration contained in a halogen-fluoride-containing gas. Background Art

[0002] Halogen fluorides are used for etching gases and cleaning gases in semiconductor manufacturing processes. In recent years, the miniaturization of semiconductors has been advancing, and high-purity gases are required for etching gases and cleaning gases used in semiconductor manufacturing processes. In order to prepare high-purity gases, a method is needed to accurately measure the concentration of fluorine gas, which is an impurity contained in etching gases and cleaning gases.

[0003] As a method for measuring the fluorine gas concentration, for example, Non-Patent Document 1 discloses a method for measuring the concentrations of F2, NF3, and SiF4 generated when a semiconductor manufacturing process device is cleaned with NF3 gas using a quadrupole mass spectrometer.

[0004] In addition, Patent Document 1 discloses a method for analyzing halogen gas generated from a semiconductor manufacturing process by ultraviolet-visible absorption spectroscopy. It discloses that a metal passivated with fluorine gas is used as a member constituting a sample unit that introduces a gas to be measured and irradiates UV-visible light. On the other hand, since fluorine gas measurement by a mass spectrometer needs to be performed in a high vacuum environment, there are problems such as the location and time required for the vacuum pump to be used, as well as corrosion problems on components such as an ion source, a detector, and a pump, which indicates that it is not suitable to use a mass spectrometer for the measurement of fluorine gas concentration.

[0005] Prior art literature

[0006] Patent Document 1: U.S. Patent No. 6,686,594

[0007] Non-patent document 1: Electrochemical Society Proceeding, Vol. 99-8, p. 40-51 Summary of the invention

[0008] When using a mass spectrometer to measure fluorine gas concentration, fluorine gas (F2) reacts with metal components such as pipes and capillaries on the gas flow path and trace impurities such as water on the flow path due to its extremely high reactivity. Therefore, the fluorine gas to be measured is consumed by this reaction on the gas flow path, causing measurement errors when measuring fluorine gas concentration.

[0009] Therefore, an object of the present invention is to provide a high-precision measurement method for reducing the measurement error caused by the consumption of fluorine gas due to reaction with metal components such as pipes and capillaries on the gas flow path and impurities when using a mass spectrometer to measure the fluorine gas concentration contained in a halogen-containing fluoride gas.

[0010] In order to solve the above-mentioned problems, the inventors have repeatedly conducted intensive studies and found that, before using a mass spectrometer to measure the fluorine gas concentration contained in a halogen-containing fluoride gas, the pipes and capillaries present in the gas flow path in the analysis device are pre-passivated with a fluorine-containing gas to form a fluorine passivation film inside the pipes and capillaries, and at the same time remove the impurities inside, thereby enabling high-precision measurement, thereby completing the present invention. That is, the present invention includes the following [1] to [9].

[0011] [1] A method for measuring the concentration of fluorine gas, which is a method for measuring the concentration of fluorine gas (F2) contained in a halogen-containing fluoride gas using an analysis device having a halogen-containing fluoride gas supply source, a fluorine-containing gas supply source, piping, a capillary and a mass spectrometer, characterized in that before measuring the fluorine gas concentration, the piping and the capillary are passivated using a passivation gas containing the fluorine-containing gas supplied from the fluorine-containing gas supply source.

[0012] [2] According to the method for measuring fluorine gas concentration described in [1], the fluorine-containing gas is at least one gas selected from F2, HF, NF3, SF6 and halogen fluorides.

[0013] [3] The method for measuring the fluorine gas concentration according to [1] or [2], wherein the temperature for performing the passivation treatment is 70 to 500°C.

[0014] [4] The method for measuring the fluorine gas concentration according to any one of [1] to [3], wherein the passivation treatment is performed for 1 to 5 hours.

[0015] [5] The method for measuring the fluorine gas concentration according to any one of [1] to [4], wherein the concentration of the fluorine-containing gas in the passivation gas is 8 to 100% by volume.

[0016] [6] The method for measuring fluorine gas concentration according to [5], wherein the analysis device further includes a dilution gas supply source, and the concentration of the fluorine-containing gas in the passivation gas is adjusted using the dilution gas supplied from the dilution gas supply source.

[0017] [7] According to the method for measuring fluorine gas concentration described in [5] or [6], the dilution gas is at least one selected from helium, argon, nitrogen (N2), carbon dioxide and carbon tetrafluoride.

[0018] [8] According to the method for measuring the fluorine gas concentration described in any one of [1] to [7], the halogen fluoride constituting the halogen fluoride-containing gas is at least one selected from chlorine monofluoride, chlorine trifluoride, bromine monofluoride, bromine trifluoride, bromine pentafluoride, iodine monofluoride, iodine trifluoride, iodine pentafluoride and iodine heptafluoride.

[0019] [9] A device for measuring fluorine gas concentration, comprising a halogen-containing fluoride gas supply source, a fluorine-containing gas supply source, piping, a capillary and a mass spectrometer, wherein the piping and the capillary are passivated using a passivation gas containing the fluorine-containing gas supplied from the fluorine-containing gas supply source.

[0020] According to the present invention, the concentration of fluorine gas contained in the halogen-containing fluoride gas can be measured with high accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of an example of an analysis device used for measuring the fluorine gas concentration of the present invention. DETAILED DESCRIPTION

[0022] Below, refer to Figure 1 One embodiment of the present invention is described in detail. Figure 1 One embodiment of the present invention is a method for measuring the concentration of fluorine gas (F2) contained in a halogen-containing fluoride gas using an analysis device 10 having a halogen-containing fluoride gas supply source 16, a fluorine-containing gas supply source 14, a pipe 24, a capillary 28 and a mass spectrometer 30. Before measuring the fluorine gas concentration, the pipe 24 and the capillary 28 (hereinafter also referred to as "pipes, etc.") are passivated using a fluorine-containing gas.

[0023] <Analysis Device 10>

[0024] (Halogen-containing fluoride gas supply source 16)

[0025] The halogen-containing fluoride gas supply source 16 included in the analysis device 10 used in one embodiment of the present invention supplies a halogen-containing fluoride gas containing fluorine gas as a measurement object. As long as the halogen-containing fluoride gas can be supplied to the piping and the like described later and the mass spectrometer 30, there is no particular limitation on the supply method, form, size, etc. of the halogen-containing fluoride gas supply source 16. For example, the halogen-containing fluoride gas supply pipe connected to the etching device in the semiconductor manufacturing process can be branched, and the halogen-containing fluoride gas can be supplied to the piping 24 described later from the branch pipe through the valve 40, or the halogen-containing fluoride gas can be supplied to the piping 24 from a container such as a gas cylinder storing the same halogen-containing fluoride gas as the gas supplied to the etching device. When the halogen-containing fluoride gas supply source 16 is connected to the pipe 24 via a flow control device (Mass Flow Controller; MFC) 20, it is preferred from the perspective of easily adjusting the flow rate from the halogen-containing fluoride gas supply source 16 and easily adjusting the fluorine gas concentration contained in the halogen-containing fluoride gas when measured by the mass spectrometer 30.

[0026] The halogen fluoride contained in the halogen fluoride-containing gas is a fluorine compound containing halogens such as chlorine, bromine and iodine as constituent elements. As halogen fluorides, for example, chlorine monofluoride, chlorine trifluoride, bromine monofluoride, bromine trifluoride, bromine pentafluoride, iodine monofluoride, iodine trifluoride, iodine pentafluoride and iodine heptafluoride can be cited. Among them, from the viewpoint of frequency of use, chlorine trifluoride, bromine trifluoride, bromine pentafluoride, iodine pentafluoride and iodine heptafluoride are preferred, and chlorine trifluoride, iodine heptafluoride and bromine pentafluoride can be more preferably applied to the present invention. The halogen fluoride-containing gas can contain one halogen fluoride alone, or it can contain multiple halogen fluorides.

[0027] In addition, the halogen-containing fluoride gas supplied from the halogen-containing fluoride gas supply source 16 may also contain fluorine gas to be measured and impurity gases other than fluorine gas. Examples of the impurity gas include helium, argon, oxygen (O2), nitrogen (N2), carbon dioxide, and carbon tetrafluoride. The halogen-containing fluoride gas may contain one or more impurity gases, and the content thereof is not particularly limited.

[0028] (Fluorine-containing gas supply source 14)

[0029] The fluorine-containing gas supply source 14 included in the analysis device used in one embodiment of the present invention supplies fluorine-containing gas for the later-described passivation treatment of the later-described piping, etc. The fluorine-containing gas supply source 14 is not particularly limited in its supply method, form, size, etc. as long as it can supply the fluorine-containing gas to the piping, etc. For example, a gas cylinder storing fluorine-containing gas, or a gas cylinder storing fluorine-containing gas and a gas cylinder storing dilution gas can be combined to supply a passivation gas containing fluorine-containing gas to the piping 24. In addition, a fluorine generator can also be used as the fluorine-containing gas supply source 14.

[0030] The fluorine-containing gas is a gas containing fluorine as a constituent element, and there is no particular limitation as long as the passivation treatment can be performed. Examples of the fluorine-containing gas include F2, HF, NF3, SF6, and halogen fluorides. Among them, from the viewpoint of easily forming a passivation film, F2 and halides are preferred, and F2 is more preferred. A single fluorine-containing gas may be used, or multiple fluorine-containing gases may be used.

[0031] From the viewpoint of adjusting the flow rate of the fluorine-containing gas supplied from the fluorine-containing gas supply source 14 and facilitating the adjustment of the concentration of the fluorine-containing gas during the passivation treatment, the fluorine-containing gas supply source 14 is preferably connected to the pipe 24 via a flow control device 36. A valve 22 is preferably provided between the fluorine-containing gas supply source 14 and the flow control device 36.

[0032] (Dilution gas supply source 12)

[0033] The analysis device 10 used in one embodiment of the present invention preferably has a dilution gas supply source 12. The dilution gas supplied from the dilution gas supply source 12 is preferably used for diluting the fluorine-containing gas in the passivation gas and diluting the halogen-containing fluoride gas measured by the mass spectrometer 30. There is no particular limitation on the supply method, form, size, etc. of the dilution gas supply source 12 as long as it can be supplied to the piping and the mass spectrometer 30. For example, the dilution gas may be supplied to the piping 24 from a container such as a gas cylinder storing the dilution gas.

[0034] The diluent gas is a gas that is inert to the above-mentioned halogen fluoride, fluorine-containing gas and impurity gas. As the diluent gas, for example, helium, argon, N2, carbon dioxide, and carbon tetrafluoride can be cited. Among them, helium and N2 are preferred in that they have a large molecular weight difference with F2 and good analytical accuracy, and N2 is more preferred.

[0035] In order to easily adjust the flow rate of the dilution gas supplied from the dilution gas supply source 12, and to easily adjust the fluorine gas concentration contained in the halogen-containing fluoride gas when measured by the mass spectrometer 30, and the fluorine-containing gas concentration during the passivation treatment, it is preferred that the dilution gas supply source 12 is connected to the pipe 24 via the flow control device 18. It is preferred that a valve 38 is provided between the dilution gas supply source 12 and the flow control device 18.

[0036] (Pipe 24 and capillary tube 28)

[0037] The pipe 24 included in the analysis device 10 used in one embodiment of the present invention is a gas flow path pipe that connects a series of gas supply sources including the halogen-containing fluoride gas supply source 16, the fluorine-containing gas supply source 14, and preferably the dilution gas supply source 12 to the capillary 28 described later, and is used to introduce the halogen-containing fluoride gas, the fluorine-containing gas, and preferably the dilution gas into the capillary 28. The inner diameter of the pipe 24 can be appropriately set according to the gas flow rate, and is preferably 3 to 50 mm, and more preferably 6 to 25 mm.

[0038] The halogen-containing fluoride gas supply source 16, the fluorine-containing gas supply source 14, and preferably the dilution gas supply source 12 are connected to the pipe 24. Although the connection position is not particularly limited, it is preferably connected so that the pipe 24 can be sufficiently passivated. In addition, the pipe 24 may also have a valve 42 and an exhaust port 26 for discharging the fluorine-containing gas after the passivation treatment.

[0039] The capillary 28 included in the analysis device 10 used in one embodiment of the present invention is a gas flow path tube that connects the above-mentioned pipe 24 to the mass spectrometer 30 described later, and is used to adjust the amount of halogen-containing fluoride gas introduced into the mass spectrometer 30. The flow path cross-sectional area of ​​the capillary 28 is smaller than that of the pipe 24, and the inner diameter of the capillary 28 can be appropriately set in accordance with the gas flow rate, preferably 0.1 to 5 mm, more preferably 1 to 2 mm.

[0040] The material of the pipe and the capillary is not particularly limited as long as it is corrosion-resistant to the components contained in the halogen-containing fluoride gas and the fluorine-containing gas and heat-resistant to the heating during the passivation treatment. Examples of the material of the pipe and the like include stainless steel, nickel, Inconel alloy, and Monel alloy.

[0041] (Mass Spectrometer 30)

[0042] The mass spectrometer 30 included in the analysis device 10 used in one embodiment of the present invention is used to measure the fluorine gas concentration contained in the halogen-containing fluoride. As long as it can quantitatively analyze a mixed gas of a single or multiple trace components, and a mixed gas of a single or multiple trace components and a single or multiple large components, the mass spectrometer 30 is not particularly limited. As the mass spectrometer 30, for example, a quadrupole mass spectrometer, a double focusing mass spectrometer, an ion trap mass spectrometer, a time-of-flight mass spectrometer, and an ion cyclotron mass spectrometer can be cited. The mass spectrometer 30 may include a vacuum pump 32 and an exhaust port 34.

[0043] <Passivation treatment>

[0044] (Handling method)

[0045] In one embodiment of the present invention, the passivation treatment refers to a treatment in which a passivation film of fluorine is formed on the internal surface of a pipe or the like using a passivation gas containing the above-mentioned fluorine-containing gas, while removing impurities such as water. The passivation gas is a gas used in the passivation treatment, which contains a fluorine-containing gas or a fluorine-containing gas (mixed gas) diluted by the above-mentioned diluent gas. The passivation treatment can be carried out in a state where the inside of the pipe or the like is sealed with a passivation gas by closing a valve 26 arbitrarily provided on the pipe or the like, or by allowing the above-mentioned passivation gas to circulate in the pipe or the like with the valve 26 opened. The flow rate when the above-mentioned passivation gas is circulated can be appropriately set according to the time and temperature of the passivation treatment, the inner diameter of the pipe or the like, for example, when the inner diameter of the pipe 24 is 3 to 8 mm and the inner diameter of the capillary 28 is 0.5 to 1.5 mm, the total flow rate of the fluorine-containing gas and the diluent gas is 40 to 60 mL / min. The passivation treatment does not need to be repeated unless such treatment as opening the inside of the piping to the outside air to change the internal surface of the piping is performed. However, from the perspective of stable measurement, it can be performed regularly, such as once a day, once a month, or once a year.

[0046] (temperature)

[0047] The temperature for the passivation treatment is preferably higher than the temperature for measuring the fluorine gas concentration contained in the halogen-containing fluoride gas, and specifically preferably 70 to 500°C. When the temperature for the passivation treatment is lower than the lower limit of the above range, the passivation film of fluorine is not formed sufficiently, and the fluorine in the halogen fluoride is consumed in the piping, etc., so the measurement accuracy is reduced. In addition, if the temperature for the passivation treatment is higher than the upper limit of the above range, the passivation film of fluorine is peeled off, and the metal surface of the piping, etc. is corroded. The temperature for the passivation treatment is more preferably 80 to 400°C, and more preferably 100 to 300°C.

[0048] (time)

[0049] The time for passivation treatment is preferably 1 to 5 hours. If the time for passivation treatment is shorter than the lower limit of the above range, the formation of the passivation film is insufficient, and the fluorine in the halogen fluoride is consumed in the piping, etc., so the measurement accuracy is reduced. In addition, if the time for passivation treatment is longer than the above range, the ratio of the effect to the treatment time becomes smaller. The time for passivation treatment is more preferably 2 to 4 hours.

[0050] (Fluorine-containing gas concentration)

[0051] The concentration of fluorine-containing gas in the passivation gas during the passivation treatment is preferably 8 to 100 volume %. As a gas other than the fluorine-containing gas in the passivation gas, the above-mentioned diluent gas is preferably used. When the concentration of the fluorine-containing gas is lower than the lower limit of the above range, the passivation film of fluorine is not formed sufficiently, and the fluorine in the halogen fluoride is consumed in the piping, etc., so the measurement accuracy is reduced. The concentration of fluorine-containing gas in the passivation gas during the passivation treatment is more preferably 10 to 100 volume %, further preferably 30 to 100 volume %, and particularly preferably 50 to 100 volume %. In addition, the concentration of fluorine-containing gas during the passivation treatment is preferably equal to or higher than the concentration of halogen fluoride contained in the halogen fluoride gas, and more preferably higher than the concentration of fluorine gas when measuring the concentration of fluorine gas contained in the halogen fluoride gas.

[0052] The concentration of the fluorine-containing gas in the passivation gas can be adjusted by adjusting the flow rates of the gases supplied from the fluorine-containing gas supply source 14 and the dilution gas supply source 12. For example, when the fluorine-containing gas concentration in the passivation gas is 70% by volume of the fluorine-containing gas concentration of the fluorine-containing gas supply source 14, the flow rates of the gases are adjusted so that the ratio of the flow rate of the fluorine-containing gas supplied from the fluorine-containing gas supply source 14 to the flow rate of the dilution gas supplied from the dilution gas supply source 12 becomes 7:3 at the same pressure.

[0053] <Determination of fluorine gas concentration>

[0054] The concentration of fluorine gas contained in the halogen-containing fluoride gas is measured by first performing the above-mentioned passivation treatment to fully remove the fluorine-containing gas from the pipe 24, the capillary 28 and the mass spectrometer 30, and then not supplying the fluorine-containing gas from the fluorine-containing gas supply source 14. Next, the halogen-containing fluoride gas is supplied from the halogen-containing fluoride gas supply source 16 to the pipe, etc., diluted with a diluent gas as needed, and introduced into the mass spectrometer 30 to measure the concentration of fluorine gas contained in the halogen-containing fluoride gas.

[0055] The halogen-containing fluoride gas during measurement by the mass spectrometer 30 is preferably diluted to 1 to 90% by volume, more preferably 5 to 70% by volume, and even more preferably 10 to 50% by volume using a diluent gas.

[0056] The dilution of the halogen-containing fluoride gas is performed by adjusting the flow rates of the gases supplied from the halogen-containing fluoride gas supply source 16 and the dilution gas supply source 12. For example, when the halogen-containing fluoride gas is diluted to 40% by volume, the flow rates of the gases are adjusted so that the ratio of the flow rate of the halogen-fluoride gas supplied from the halogen-containing fluoride gas supply source 16 to the flow rate of the dilution gas supplied from the dilution gas supply source 12 becomes 4:6 at the same pressure, thereby preparing a mixed gas of the halogen-containing fluoride gas and the dilution gas.

[0057] The halogen-containing fluoride gas supplied from the halogen-containing fluoride gas supply source 16 or the mixed gas of the halogen-containing fluoride gas and the diluent gas adjusted as described above is introduced into the mass spectrometer 30 via the pipe 24 and the capillary 28. The fluorine gas concentration contained in the halogen-containing fluoride gas is measured according to the manual of the mass spectrometer 30 used.

[0058] Example

[0059] Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to these Examples.

[0060] [Example 1]

[0061] Chlorine trifluoride gas is used as the halogen-containing fluoride gas, F2 is used as the fluorine-containing gas in the passivation gas, and Figure 1 The analytical device 10 shown in the figure measures the concentration of fluorine gas contained in chlorine trifluoride gas according to the measuring method of the present invention. The pipe 24 contained in the analytical device 10 is made of SUS316 and has an inner diameter of 6 mm. In addition, the capillary 28 is made of SUS316 and has an inner diameter of 1 mm. The mass spectrometer 30 uses a quadrupole mass spectrometer (manufactured by HIDEN ANALYTICAL: HPR-20), and measures the fluorine gas concentration according to the product accessory manual.

[0062] From the F2 gas cylinder as the fluorine-containing gas supply source 14 for passivation treatment, F2 with a flow rate adjusted to 50 mL / min is supplied to the piping, etc. via a flow control device 36 (trade name: digital mass flow controller SEC-N100, manufactured by HORIBA STEC). In addition, using N2 as a diluent gas, N2 with a flow rate adjusted to 50 mL / min is supplied to the piping, etc. from the N2 gas cylinder as the dilution gas supply source 12 via a flow control device 18 (trade name: digital mass flow controller SEC-N100, manufactured by HORIBA STEC). In a state where the two gases are supplied to the piping 24 at the above flow rates, the piping 24 and the capillary 28 are heated at 200° C. for 3 hours, and the inside of the piping, etc. is passivated using a mixed gas (1) of F2 and N2 as the passivation gas.

[0063] The supply of gas from the F2 gas cylinder and the N2 gas cylinder to the piping etc. was stopped, and the passivation treatment was terminated. The exhaust port 26 was opened to exhaust the mixed gas (1) from the piping etc. and then replaced with N2. The exhaust port 26 was closed, and the passivation gas in the piping and the capillary was fully exhausted by the vacuum pump 32. Then, the mixed gas (2) of chlorine trifluoride gas and N2 with the flow rate adjusted to 50 mL / min was supplied to the piping etc. from the chlorine trifluoride gas cylinder as the halogen fluoride gas supply source 16 and the N2 gas cylinder as the dilution gas supply source 12 through the flow control device 20 (trade name: digital mass flow controller SEC-N100, manufactured by HORIBA STEC Co., Ltd.) and 18. The fluorine gas concentration in the chlorine trifluoride gas diluted with N2 to 50% by volume was measured by the mass spectrometer 30 under the condition of 25°C. As a result, the fluorine gas concentration after dilution with N2 was 4 volume ppm. Therefore, the fluorine gas concentration contained in the chlorine trifluoride gas supplied from the chlorine trifluoride-containing gas supply source 16 before being diluted with N 2 is 8 volume ppm.

[0064] [Example 2]

[0065] The fluorine gas concentration was measured in the same manner as in Example 1 except that the halogen-containing fluoride gas was replaced with iodine heptafluoride gas instead of chlorine trifluoride gas. As a result, the fluorine gas concentration contained in the iodine heptafluoride gas supplied from the halogen-containing fluoride gas supply source 16 was 6 volppm.

[0066] [Example 3]

[0067] The fluorine gas concentration was measured in the same manner as in Example 1 except that the halogen-containing fluoride gas was replaced with bromine pentafluoride gas instead of chlorine trifluoride gas. As a result, the fluorine gas concentration contained in the bromine pentafluoride gas supplied from the halogen-containing fluoride gas supply source 16 was 10 volppm.

[0068] [Comparative Example 1]

[0069] The fluorine gas concentration contained in the chlorine trifluoride gas was measured in the same manner as in Example 1 except that the passivation treatment was not performed, but fluorine gas was not detected.

[0070] [Examples 4 to 9]

[0071] The fluorine gas concentration in the chlorine trifluoride gas was measured in the same manner as in Example 1 except that the temperature conditions during the passivation treatment were set to the temperatures described in Table 1 below. Table 1 shows the results of the fluorine gas concentration in the chlorine trifluoride gas supplied from the halogen-containing fluoride gas supply source 16 .

[0072] Table 1

[0073]

[0074] [Examples 10 to 15]

[0075] The fluorine gas concentration contained in the chlorine trifluoride gas before dilution was obtained in the same manner as in Example 1 except that the F2 concentration used in the passivation treatment was set to the concentration shown in Table 2 below. The results are shown in Table 2. In Example 10, since the dilution of F2 with N2 was not performed during the passivation treatment, the measured value of the fluorine gas concentration is directly shown in Table 2.

[0076] Table 2

[0077]

[0078] Description of Reference Numerals

[0079] 10…Analysis device

[0080] 12…Dilution gas supply source

[0081] 14…Fluorine-containing gas supply source

[0082] 16… Halogen-containing fluoride gas supply source

[0083] 18, 20, 36…Flow control device

[0084] 22, 38, 40, 44… valves

[0085] 24…Piping

[0086] 26…Exhaust port

[0087] 28…Capillary

[0088] 30…Mass spectrometer

[0089] 32…Vacuum pump

[0090] 34…Exhaust port

Claims

1. A method for measuring the concentration of fluorine gas, which is a method for measuring the concentration of fluorine gas, i.e., F2, contained in the halogen-containing fluoride gas using an analysis device having a halogen-containing fluoride gas supply source, a fluorine-containing gas supply source, a pipe, a capillary, and a mass spectrometer, wherein: Before measuring the fluorine gas concentration, the pipe and the capillary are subjected to a passivation treatment at 70 to 500° C. using a passivation gas containing a fluorine-containing gas supplied from the fluorine-containing gas supply source.

2. The method for measuring fluorine gas concentration according to claim 1, The fluorine-containing gas is at least one gas selected from F2, HF, NF3, SF6 and halogen fluoride.

3. The method for measuring fluorine gas concentration according to claim 1 or 2, The passivation treatment is performed for 1 to 5 hours.

4. The method for measuring fluorine gas concentration according to claim 1 or 2, The concentration of the fluorine-containing gas in the passivation gas is 8 to 100 volume %.

5. The method for measuring fluorine gas concentration according to claim 4, The analysis device further includes a dilution gas supply source, and uses the dilution gas supplied from the dilution gas supply source to adjust the concentration of the fluorine-containing gas in the passivation gas.

6. The method for measuring fluorine gas concentration according to claim 5, The diluent gas is at least one selected from helium, argon, nitrogen, carbon dioxide and carbon tetrafluoride.

7. The method for measuring fluorine gas concentration according to claim 1 or 2, The halogen fluoride constituting the halogen fluoride-containing gas is at least one selected from chlorine monofluoride, chlorine trifluoride, bromine monofluoride, bromine trifluoride, bromine pentafluoride, iodine monofluoride, iodine trifluoride, iodine pentafluoride and iodine heptafluoride.

8. A device for measuring fluorine gas concentration, comprising a halogen-containing fluoride gas supply source, a fluorine-containing gas supply source, piping, a capillary and a mass spectrometer, wherein the piping and the capillary are passivated using a passivation gas containing fluorine-containing gas supplied from the fluorine-containing gas supply source.

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