JPH04177157A - Method for analyzing gas - Google Patents
Method for analyzing gasInfo
- Publication number
- JPH04177157A JPH04177157A JP30557790A JP30557790A JPH04177157A JP H04177157 A JPH04177157 A JP H04177157A JP 30557790 A JP30557790 A JP 30557790A JP 30557790 A JP30557790 A JP 30557790A JP H04177157 A JPH04177157 A JP H04177157A
- Authority
- JP
- Japan
- Prior art keywords
- gas
- sample
- concn
- analyzer
- impurity
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims description 7
- 238000004458 analytical method Methods 0.000 claims description 15
- 238000004868 gas analysis Methods 0.000 claims description 6
- 239000007789 gas Substances 0.000 abstract description 87
- 239000012535 impurity Substances 0.000 abstract description 28
- 238000010790 dilution Methods 0.000 abstract description 7
- 239000012895 dilution Substances 0.000 abstract description 7
- 238000007865 diluting Methods 0.000 abstract description 6
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 abstract description 4
- 230000035945 sensitivity Effects 0.000 abstract description 3
- 239000007788 liquid Substances 0.000 abstract description 2
- 229910052757 nitrogen Inorganic materials 0.000 abstract description 2
- 150000002500 ions Chemical class 0.000 description 8
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 5
- 229910001882 dioxygen Inorganic materials 0.000 description 5
- XYFCBTPGUUZFHI-UHFFFAOYSA-N Phosphine Chemical compound P XYFCBTPGUUZFHI-UHFFFAOYSA-N 0.000 description 4
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 2
- RBFQJDQYXXHULB-UHFFFAOYSA-N arsane Chemical compound [AsH3] RBFQJDQYXXHULB-UHFFFAOYSA-N 0.000 description 2
- 239000012159 carrier gas Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- PZPGRFITIJYNEJ-UHFFFAOYSA-N disilane Chemical compound [SiH3][SiH3] PZPGRFITIJYNEJ-UHFFFAOYSA-N 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 229910000073 phosphorus hydride Inorganic materials 0.000 description 2
- 229910000077 silane Inorganic materials 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 238000002290 gas chromatography-mass spectrometry Methods 0.000 description 1
- 238000001871 ion mobility spectroscopy Methods 0.000 description 1
- 238000000752 ionisation method Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000012929 ultra trace analysis Methods 0.000 description 1
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、サンプルガス中の測定すべきガス濃度を広い
範囲にわたって高精度で分析することができるようにし
たガス分析方法に関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a gas analysis method that allows the concentration of a gas to be measured in a sample gas to be analyzed over a wide range with high precision.
従来の技術
このような広い範囲にわたるガスの分析は、高純度ガス
を必要とする半導体産業分野、高精度のガス分析を必要
とする分析業界、および希望する濃度を有する標準ガス
を扱う業界などにおいて必要となる。Conventional technology The analysis of such a wide range of gases is useful in the semiconductor industry, which requires high-purity gases, the analytical industry, which requires highly accurate gas analysis, and the industry, which handles standard gases with desired concentrations. It becomes necessary.
従来から、ガス中の極微量成分の分析計とじては、たと
えばＡＰＩ−ＭＳ（＾ｔｏｍｏｓｐｈｅｒｉｃＰｒｅｓ
ｕｒｅ Ｉｏｎｉｚａｔｉｏｎ Ｍａｓｓ ５ｐｅｅｔ
ｏｒｏｅ＋ｅｔｅｒ大気圧質量分析計）がある。この装
置を用いることによって、酸素ガス中の不純物の極微量
分析を行うことができるけれども、その微量成分の分析
は困難である。またこの装置では、たとえばｐｐｔオー
ダの測定は可能であるけれども、ガス中の不純物濃度が
数ｐｐｍ程度以上では、分析が困難である。Conventionally, as an analyzer for ultratrace components in gas, for example, API-MS (^tomospheric Pres
ure Ionization Mass 5peet
oroe+eter atmospheric pressure mass spectrometer). Although it is possible to analyze trace amounts of impurities in oxygen gas using this device, analysis of trace components is difficult. Further, although this device is capable of measuring, for example, ppt order, it is difficult to analyze when the impurity concentration in the gas is several ppm or more.
発明が解決すべき課題
本発明の目的は、広い範囲にわたる濃度を有するガスの
分析を行うことができるガス分析方法を提供することで
ある。Problems to be Solved by the Invention An object of the present invention is to provide a gas analysis method that can analyze gases having concentrations over a wide range.
課題を解決するための手段
本発明は、測定すべき種類のガスを含むサンプルガスを
、ゼロガスによって高精度で希釈し、この希釈されたガ
スを、高感度分析計に導いて分析を行うことを特徴とす
るガス分析方法である。Means for Solving the Problems The present invention involves diluting a sample gas containing the type of gas to be measured with zero gas with high precision, and guiding this diluted gas to a highly sensitive analyzer for analysis. This is a characteristic gas analysis method.
作 用
本発明に従えば、サンプルガスは、測定すべき種類のガ
スを含み、たとえば酸素ガス中に不純物を含み、このよ
うなサンプルガスをゼロガスによって高精度で希釈して
、希望する濃度とし、この希釈されたガスを、高感度分
析計、たとえばＡＰＩ−ＭＳに導いて、サンプルガス中
の不純物として含まれているガスの種類および濃度を測
定する。According to the present invention, the sample gas contains the type of gas to be measured, for example, oxygen gas contains impurities, and such sample gas is diluted with zero gas with high precision to a desired concentration, This diluted gas is introduced into a highly sensitive analyzer, such as API-MS, to measure the type and concentration of gases contained as impurities in the sample gas.
これによって高感度分析計の極微量成分の可能な分析範
囲以外の高濃度であっても、広い濃度の範囲にわたって
、ガス分析を行うことができる。高感度分析計は、前述
のたとえばＡＰ Ｉ−ＭＳだけでなく、たとえばＧＣ−
ＭＳ （ガスクロマトグラフ質量分析計）などであって
もよく、ｔたその他の構成であってもよい。As a result, gas analysis can be performed over a wide concentration range, even if the concentration is high beyond the analysis range of extremely trace components of a high-sensitivity analyzer. Highly sensitive analyzers include not only the above-mentioned AP I-MS, but also GC-MS.
It may be an MS (gas chromatograph mass spectrometer) or the like, or may have other configurations.
実施例
第１図は、本発明の一実施例の全体の系統図である。管
路１からは、サンプルガスが供給されて高性能希釈手段
２に導かれる。高性能希釈手段２は、■当装置とガスが
接触する部分（たとえば、配管系）からの不純物の混入
（すなわち、装置材料に付着している不純物がガス中に
混入すること）がない、■設定した希釈倍数に精密に希
釈できる、という主には以上２点の特徴を有するもので
ある。Embodiment FIG. 1 is an overall system diagram of an embodiment of the present invention. A sample gas is supplied from the pipe line 1 and guided to the high performance dilution means 2. The high-performance diluting means 2 is characterized by: (i) There is no contamination of impurities from parts where the device and the gas come into contact (e.g., piping system) (i.e., impurities attached to the device material are not mixed into the gas); (i) It has the following two main features: it can be diluted precisely to a set dilution ratio.
サンプルガスは、たとえば酸素ガスなどであってもよく
、その酸素ガス中に微量含まれる不純物ガスの分析を、
次に述べるようにして行うことができる。希釈手段２に
は、Ｈｅガス供給源３がら液体窒素を用いたトラップ４
を軽で、高純度のＨｅガスをゼロガスとして、希釈手段
２に供給される。The sample gas may be, for example, oxygen gas, and analysis of impurity gases contained in trace amounts in the oxygen gas is performed.
This can be done as described below. The dilution means 2 includes a He gas supply source 3 and a trap 4 using liquid nitrogen.
The light and high purity He gas is supplied to the diluting means 2 as zero gas.
このゼロガスというのは、不純物の含まれないガスであ
って、たとえばガスクロマトグラフィ装置におけるキャ
リアガスとして用いられるものである。希釈手段２では
、管路ｌがらのサンプルガスを、管路５がちのＨｅガス
で高精度で希釈し、たとえばサンプルガスを１０−’〜
１ｏ−６程度まで高精度で希釈することができる性能を
有している。This zero gas is a gas that does not contain impurities, and is used, for example, as a carrier gas in a gas chromatography apparatus. The diluting means 2 dilutes the sample gas in the pipe line 1 with He gas in the pipe line 5 with high accuracy, for example, the sample gas is diluted by 10-'~
It has the ability to dilute with high precision up to about 1o-6.
こうして希釈されたガスは、管路６がら、ＡＰＩ−ＭＳ
ｌ！ｌｆなどのような高感度分析計７に、流量制御弁８
を介して供給され、余分′なガスは管路９から外部に排
出される６分析計７の検出感度は、１ｐｐｔ程度であり
、その検出可能な濃度範囲は比教的狭い、希釈手段２で
は、このような分析可能な濃度範囲に、測定すべき種類
のガスが含まれるように、管路６がら得られるガスの希
釈率を変化して調整する。したがって分析計７によって
分析が不可能である高濃度の測定すべき種類のガスを含
むサンプルガスであっても、その測定すべき種類のガス
の濃度および種類を高精度で検出して分析することが可
能である。The gas diluted in this way is passed through the pipe 6 to the API-MS.
l! A flow control valve 8 is connected to a high-sensitivity analyzer 7 such as lf.
The detection sensitivity of the analyzer 7 is about 1 ppt, and the detectable concentration range is relatively narrow. The dilution rate of the gas obtained from the pipe 6 is adjusted so that the type of gas to be measured is included in such an analyzable concentration range. Therefore, even if the sample gas contains a high concentration of the type of gas to be measured that cannot be analyzed by the analyzer 7, the concentration and type of the type of gas to be measured can be detected and analyzed with high accuracy. is possible.
分析計７では、一般に０．、ＣＨ，、シラン、ジシラン
、ホスフィン、アルシンなどのイオン化ポテンシャルが
これらガス中の不純物ガスのイオン化ポテンシャルより
小さいため、不純物ガス濃度の極微量分析は困難である
が、Ｈｅガスで希釈することにより、Ｈｅガスのイオン
化ポテンシャルの方が不純物ガスのイオン化ポテンシャ
ルより高いために、極微量分析が可能となるのである。In analyzer 7, generally 0. , CH, , Because the ionization potential of silane, disilane, phosphine, arsine, etc. is smaller than the ionization potential of impurity gases in these gases, it is difficult to analyze the impurity gas concentration in extremely small quantities, but by diluting with He gas, Since the ionization potential of He gas is higher than the ionization potential of impurity gas, ultra-trace analysis becomes possible.
なお、イオン化ポテンシャルの違いによる分析のＪ［Ｉ
Ｉは「三井泰裕 “ＵＬＳ Ｉ層高純度ガス中の超微−
不純物分析技術″応用物理第５６巻第１１号（１９８７
）Ｊの第１４６７頁〜第１４６８頁ｒ３．ＡＰＩＭＳ原
理」に記載されている。すなわち微量の不純物を含んだ
試料ガス（主成分：Ｃ１不純物：Ｓ）がイオン源に導入
され、コロナ放電または”Ｎ ｉのβ線によって、−次
イオン化が行われる。このとき試料の一部分がイオン化
される。生成されたイオンの組成は試料とほぼ同じで、
大部分の主成分イオンＣ゛と、ゎずがの不純物イオンＳ
゛よりなる。大気圧イオン化法では、次の二次イオン化
を利用してＳ゛の増大を図っている。すなわち、−次イ
オン化で生成されたイオンのうち、Ｃ゛は分析目的に対
して不要のイオンである。このＣ゛がら、イオン化され
ないで残っている試料中の中性分子Ｓへの電荷交換反応
により、電荷を移動させる方法である。゛通常、キャリ
アガス分子（Ｎ２．Ｈ，、Ａｒ、Ｈｅなど）は、不純物
分子（Ｈ２Ｏ，ＣＯｔ、有機物など）よりイオン化ポテ
ンシャルが高いので、電荷交換反応は高速に進行し、逆
反応は起こらない。Note that J[I of analysis due to differences in ionization potential
I is “Yasuhiro Mitsui “ULS I layer ultrafine in high purity gas”
“Impurity Analysis Technology” Applied Physics Vol. 56 No. 11 (1987
) J pages 1467-1468 r3. APIMS Principles”. That is, a sample gas containing a trace amount of impurity (main component: C1 impurity: S) is introduced into the ion source, and negative ionization is performed by corona discharge or β rays of Ni. At this time, a part of the sample is ionized. The composition of the generated ions is almost the same as that of the sample,
Most of the main component ions C゛ and ゎZuga impurity ions S
It consists of ゛. In the atmospheric pressure ionization method, the following secondary ionization is utilized to increase S'. That is, among the ions generated by negative ionization, C' is an ion unnecessary for the purpose of analysis. This is a method in which charges are transferred by a charge exchange reaction to neutral molecules S in the sample that remain unionized.゛Normally, carrier gas molecules (N2.H, Ar, He, etc.) have a higher ionization potential than impurity molecules (H2O, COt, organic substances, etc.), so the charge exchange reaction proceeds quickly and no reverse reaction occurs. .
Ｓｏの量を増大させるためには、この反応機会が多いこ
とが望ましいが、そのためには、減圧状態よりも１気圧
（１０’ Ｐａ）のような高圧状態が必要となる。すな
わち、高圧下では平均自由工程が短く、粒子衝突確率が
高い。現在実用化されているＡＰ Ｉ ＭＳのイオン源
内では、１個の粒子が１０７回程度の衝突を起こしてい
るので、分析目的成分のイオンＳ゛を増大させることが
可能となり、この増大されたＳ゛が分析部に導入される
ので、ＡＰ−ＭＳは微量物質に対する高感度化が図れる
ことになる。In order to increase the amount of So, it is desirable to have many opportunities for this reaction, but for this purpose, a high pressure state such as 1 atm (10' Pa) is required rather than a reduced pressure state. That is, under high pressure, the mean free path is short and the probability of particle collision is high. In the ion source of the AP I MS that is currently in practical use, one particle causes about 107 collisions, so it is possible to increase the ion S of the component to be analyzed, and this increased S Since this is introduced into the analysis section, AP-MS can be highly sensitive to trace substances.
酸素濃度をたとえばｐｐｍオーダにＨｅガスによって希
釈すると、その希釈後のガス中に含まれている不純物ガ
スの濃度がｐｐｔオーダであるとき、その不純物ガスの
分析が容易となる。このことは本発明の実施例の優れた
利点である。When the oxygen concentration is diluted with He gas to, for example, ppm order, when the concentration of impurity gas contained in the diluted gas is on the ppt order, analysis of the impurity gas becomes easy. This is a significant advantage of embodiments of the present invention.
本発明は上述のように酸素ガス中の不純物の分析、ボン
ベガス中の水分などの数ｐｐｍのＨ２Ｏの分析、ボンベ
ガス中のその他の数ｐｐｍ程度の不純物ガスの分析、さ
らにシラン、ジシラン、ホスフィンおよびアルシンなど
のようなガス中の不純物の分析、さらにまたメタンガス
中の不純物ガスの分析、およびその他のガス中の不純物
ガスの分析のために広範囲に実施することができる。As mentioned above, the present invention can analyze impurities in oxygen gas, analyze several ppm of H2O such as moisture in cylinder gas, analyze other impurity gases of about several ppm in cylinder gas, and further analyze silane, disilane, phosphine, and arsine. It can be widely implemented for the analysis of impurities in gases such as, and also for the analysis of impurity gases in methane gas and the analysis of impurity gases in other gases.
発明の効果
以上のように本発明によれば、サンプルガスを、ゼロガ
スによって高精度で希釈し、その希釈されたガスを高感
度分析計に導いて分析を行うようにしたので、サンプル
ガスに不純物として含まれているガスの濃度および種類
を、高感度分析計の可能な測定範囲外の高濃度の不純物
を含むサンプルガスにおいてもまた、適用することがで
き、このようにしてサンプルガス中に含まれている広い
濃度範囲にわたる不純物のガスの分析を行うことができ
る。Effects of the Invention As described above, according to the present invention, the sample gas is diluted with zero gas with high precision, and the diluted gas is guided to a high-sensitivity analyzer for analysis, so that there are no impurities in the sample gas. The concentration and type of gases contained in the sample gas can also be applied in sample gases containing high concentrations of impurities that are outside the possible measurement range of sensitive analyzers, and in this way the concentration and type of gases contained in the sample gas can be It is possible to analyze impurity gases over a wide concentration range.
第１図は本発明の一実施例の全体の系統図である。
１・・サンプルガス供給管、２・・・希釈手段、３・・
・Ｈｅガス供給源、４・・・トラップ手段、７・・・分
析計代理人 弁理士 画数 圭一部FIG. 1 is an overall system diagram of an embodiment of the present invention. 1... Sample gas supply pipe, 2... Dilution means, 3...
・He gas supply source, 4... Trap means, 7... Analyzer agent Patent attorney Keiichi Kazuzu
Claims (1)
によつて高精度で希釈し、 この希釈されたガスを、高感度分析計に導いて分析を行
うことを特徴とするガス分析方法。[Claims] The method is characterized in that a sample gas containing the type of gas to be measured is diluted with zero gas with high accuracy, and the diluted gas is guided to a high-sensitivity analyzer for analysis. Gas analysis methods.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30557790A JPH04177157A (en) | 1990-11-10 | 1990-11-10 | Method for analyzing gas |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30557790A JPH04177157A (en) | 1990-11-10 | 1990-11-10 | Method for analyzing gas |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04177157A true JPH04177157A (en) | 1992-06-24 |
Family
ID=17946820
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP30557790A Pending JPH04177157A (en) | 1990-11-10 | 1990-11-10 | Method for analyzing gas |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04177157A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010217021A (en) * | 2009-03-17 | 2010-09-30 | Koyo Thermo System Kk | Gas detecting apparatus and oxynitriding process facility equipped with the same |
| JP2012529639A (en) * | 2009-06-12 | 2012-11-22 | アデイクセン・バキユーム・プロダクト | Apparatus and method for analyzing gas and associated measuring station |
| CN103645269A (en) * | 2013-11-19 | 2014-03-19 | 苏州丹百利电子材料有限公司 | Analysis method and apparatus of ultra pure arsine |
| JP2017161348A (en) * | 2016-03-09 | 2017-09-14 | 富士電機株式会社 | Particle analysis device and particle analysis method |
-
1990
- 1990-11-10 JP JP30557790A patent/JPH04177157A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010217021A (en) * | 2009-03-17 | 2010-09-30 | Koyo Thermo System Kk | Gas detecting apparatus and oxynitriding process facility equipped with the same |
| JP2012529639A (en) * | 2009-06-12 | 2012-11-22 | アデイクセン・バキユーム・プロダクト | Apparatus and method for analyzing gas and associated measuring station |
| CN103645269A (en) * | 2013-11-19 | 2014-03-19 | 苏州丹百利电子材料有限公司 | Analysis method and apparatus of ultra pure arsine |
| JP2017161348A (en) * | 2016-03-09 | 2017-09-14 | 富士電機株式会社 | Particle analysis device and particle analysis method |
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