JPS6010170A - Method and apparatus for measuring concentration of ammonia and hydrogen peroxide in ammonia-oriented hydrogen peroxide liquid - Google Patents
Method and apparatus for measuring concentration of ammonia and hydrogen peroxide in ammonia-oriented hydrogen peroxide liquidInfo
- Publication number
- JPS6010170A JPS6010170A JP11697683A JP11697683A JPS6010170A JP S6010170 A JPS6010170 A JP S6010170A JP 11697683 A JP11697683 A JP 11697683A JP 11697683 A JP11697683 A JP 11697683A JP S6010170 A JPS6010170 A JP S6010170A
- Authority
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- Japan
- Prior art keywords
- hydrogen peroxide
- ammonia
- sample
- vaporization chamber
- oxygen
- Prior art date
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N31/00—Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroup; Apparatus specially adapted for such methods
- G01N31/10—Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroup; Apparatus specially adapted for such methods using catalysis
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- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Analytical Chemistry (AREA)
- Molecular Biology (AREA)
- Physics & Mathematics (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
Description
【発明の詳細な説明】
〔発明の利用分野〕
本発明は、アンモニア性過酸化水素液中のアンモニアお
よび過酸化水素の濃度を同時にかつｌ’ｉ？Ｉ潔に測定
する方法およびその装置に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention provides a method for controlling the concentration of ammonia and hydrogen peroxide in an ammoniacal hydrogen peroxide solution simultaneously and l'i? The present invention relates to a method and apparatus for accurately measuring.
半導体プロセス等で広く用いられるアンモニア性過酸化
水素洗浄液中のアンモニアと過酸化水素の濃度を測定す
る方法としては、従来はそれぞれ別個に測定することが
行われていた。すなわち、アンモニアの濃度の測定は、
妨害となる成分が少なく、応答性が早い隔膜型アンモニ
ウムイオン電極法や、塩酸や硫酸を用いた中和滴定法が
用いられていた。また、過酸化水素の濃度の測定は、モ
リブデン酸アンモニアとの呈色反応を利用した比色分析
や、過酸化水素の紫外光の特性吸収２４０ ｎｍの波長
を利用した吸光度法が用いられていた。しかし、」１記
した分析法は、いずれも操作が煩雑であるばかりでなく
、それぞれ個別に測定を行う必要があるという欠点があ
り、従って、簡便な方法で、アンモニアと過酸化水素の
濃度を同時に測定する方法とその装置の開発が必要にな
っていた。Conventionally, the concentration of ammonia and hydrogen peroxide in an ammonia-based hydrogen peroxide cleaning solution widely used in semiconductor processes and the like has been measured separately. In other words, the measurement of ammonia concentration is
The membrane-type ammonium ion electrode method, which has fewer interfering components and has a faster response, and the neutralization titration method using hydrochloric acid or sulfuric acid were used. Additionally, to measure the concentration of hydrogen peroxide, colorimetric analysis using a color reaction with ammonia molybdate and absorbance method using hydrogen peroxide's characteristic absorption of ultraviolet light at a wavelength of 240 nm have been used. . However, all of the analytical methods described in ``1'' have the drawback that they are not only complicated to operate, but also require separate measurements. It became necessary to develop a method and device for simultaneous measurement.
本発明の目的は、上記した従来技術の欠点をなくシ、ア
ンモニア性過酸化水素液中のアンモニアと過酸化水素の
濃度を同時に、簡単な手法で、簡潔に測定する方法およ
びその装置を提供するにある。An object of the present invention is to eliminate the drawbacks of the prior art described above and provide a method and apparatus for simultaneously and simply measuring the concentrations of ammonia and hydrogen peroxide in an ammoniacal hydrogen peroxide solution. It is in.
本発明は、アンモニア性過酸化水素液から試料をとり、
該試料中の過酸化水素を酸素と水とに分解し、この試料
をカスクロマトグラフに送って、アンモニア、酸素およ
び水の各成分を検出し、その検出結果を基にマイクロコ
ンピュータでアンモニアと過酸化水素の濃度を計算し、
計算結果を表示装置に表示し、これらの操作を次の試料
について順次連続して繰り返し行うというのが、その要
点である。The present invention takes a sample from an ammoniacal hydrogen peroxide solution,
Hydrogen peroxide in the sample is decomposed into oxygen and water, and this sample is sent to a gas chromatograph to detect each component of ammonia, oxygen, and water.Based on the detection results, a microcomputer separates ammonia and peroxide. Calculate the concentration of hydrogen,
The key point is to display the calculation results on a display device and repeat these operations sequentially and continuously for the next sample.
第１図は本発明の構成を明示するための全体構成図であ
る。FIG. 1 is an overall configuration diagram for clearly showing the configuration of the present invention.
上記のように、本発明の基本的な考え方は、アンモニア
と過酸化水素の濃度をガスクロマトグラフによって同時
に簡潔に測定することである。しかし、過酸化水素は分
離カラム中で水と酸素とに徐々に分解するため、ガスク
ロマトグラム中で明瞭なピークを示さず、測定が困難で
ある。そこで、本発明では、試料中の過酸化水素をあら
かじめ銅などの金属網を触媒として酸素と水とに分解し
、アンモニア、酸素および水の各成分の検出データを基
にしてアンモニアと過酸化水素の濃度を計算し測定する
ことにしたものである。なお、・この除虫じた酸素によ
り触媒上でアンモニアが酸化することも考えられるが、
１００ ℃前後の温度の金属網触媒では、過酸化水素の
反応は数秒で完了するので、アンモニアの酸化反応は本
測定が影響を受けるほどのものではない。As mentioned above, the basic idea of the present invention is to simply measure the concentrations of ammonia and hydrogen peroxide simultaneously by gas chromatography. However, since hydrogen peroxide gradually decomposes into water and oxygen in the separation column, it does not show clear peaks in a gas chromatogram, making measurement difficult. Therefore, in the present invention, hydrogen peroxide in a sample is decomposed into oxygen and water using a metal mesh such as copper as a catalyst, and ammonia and hydrogen peroxide are decomposed based on the detection data of each component of ammonia, oxygen, and water. We decided to calculate and measure the concentration of In addition, it is possible that ammonia is oxidized on the catalyst by this expelled oxygen,
With a metal mesh catalyst at a temperature of around 100° C., the reaction of hydrogen peroxide is completed in a few seconds, so the oxidation reaction of ammonia is not significant enough to affect this measurement.
アンモニア、酸素および水のガスクロマトグラムは、カ
ラムの種類によって若干異なるが、一般に第２図のよう
になり、測定するピークの出る位置（カラムに入れてか
らの時間）の間隔は一定で・ある。従って、ガスクロマ
トグラフの試料自動注入器とマイクロコンピュータ（ま
たはタイマ）とを連動させることにより繰り返し測定を
自動的に行うことができ、アンモニアと過酸化水素の濃
度の連続測定が可能となる。Gas chromatograms of ammonia, oxygen, and water differ slightly depending on the type of column, but generally they look like the one shown in Figure 2, and the intervals between the positions of the measured peaks (time after entering the column) are constant. Therefore, by linking the automatic sample injector of the gas chromatograph with a microcomputer (or timer), repeated measurements can be performed automatically, making it possible to continuously measure the concentrations of ammonia and hydrogen peroxide.
アンモニアと過酸化水素の濃度は、次のようにしてめら
れる。すなわち、あらかじめ酸素、アンモニア、水それ
ぞれの濃度換算のファクタｆ０２、ｆＮＨ３、ｆＨ２ｏ
をめておき、次の式からそれぞれの濃度が計算できる。The concentrations of ammonia and hydrogen peroxide are determined as follows. That is, the factors f02, fNH3, fH2o for concentration conversion of oxygen, ammonia, and water are calculated in advance.
The concentration of each can be calculated using the following formula.
・・・・・・（１）
・・・・・・（２）
ここで、Ｓ０２．５ＮＩ（３，５Ｈ２０は、ガスクロマ
トグラムにおける酸素、アンモニア、水それぞれのピー
ク面積である。......(1) ......(2) Here, S02.5NI (3,5H20 is the peak area of each of oxygen, ammonia, and water in the gas chromatogram.
本発明の具体的実施例につき第３図を参照して詳細に説
明する。第３図は本発明の装置の構成を示す構成図であ
る。図において、１はアンモニア性過酸化水素洗浄液を
収納した洗浄液槽で、通常６０〜８０℃に保温されてい
る。洗浄液槽１中の洗浄液はポンプ２により、８方コツ
クと２木のサンプルループをもつ試料自動注入器３の１
つのサンプルループ内に送り込まれ、排出パイプ４を通
って元の洗浄液槽１と循環している。試料自動注入器３
のサンプルループの容量は２μｔである。試料自動注入
器３のコックが測定側に切り換えられると、ヘリウムボ
ンベ１５からのヘリウムガスはサンプルループ内の試料
を気化室５へ送り込む。このときのヘリウムガスの流量
は５０ ｍＡ／ｍｉｎである。この気化室５の内部には
銅の網６がセットされており、１００℃に加温されてい
る。この気化室５内で、過酸化水素は酸素と水とに分解
される。その後、恒温槽７内の分割カラム８で、酸素、
アンモニア、水はそれぞれ分離し、保持時間の短い順に
熱伝導度検出器９に達する。熱伝導度検出器９の出力す
る信号は、増幅器１０、Ａ／Ｄ変換器１１、インタフェ
ース１２を経て、マイクロコンピュータ１３に送られ、
ここでデータ処理され、表示装置１４に表示される。A specific embodiment of the present invention will be described in detail with reference to FIG. FIG. 3 is a block diagram showing the structure of the apparatus of the present invention. In the figure, reference numeral 1 denotes a cleaning liquid tank containing an ammonia-based hydrogen peroxide cleaning liquid, which is normally kept at a temperature of 60 to 80°C. The cleaning liquid in the cleaning liquid tank 1 is pumped by the pump 2 to the sample automatic injector 3, which has an 8-way socket and 2 wooden sample loops.
The sample is fed into two sample loops and circulated through the discharge pipe 4 to the original washing liquid tank 1. Sample automatic injector 3
The capacity of the sample loop is 2 μt. When the cock of the automatic sample injector 3 is switched to the measurement side, helium gas from the helium cylinder 15 feeds the sample in the sample loop into the vaporization chamber 5. The flow rate of helium gas at this time was 50 mA/min. A copper net 6 is set inside this vaporization chamber 5, and is heated to 100°C. Within this vaporization chamber 5, hydrogen peroxide is decomposed into oxygen and water. After that, in the divided column 8 in the constant temperature bath 7, oxygen
Ammonia and water are separated and reach the thermal conductivity detector 9 in descending order of retention time. The signal output from the thermal conductivity detector 9 is sent to the microcomputer 13 via an amplifier 10, an A/D converter 11, and an interface 12.
Here, the data is processed and displayed on the display device 14.
」−記の構成において、分離カラム８に、６０〜８゜メ
ツシュのポリスチレンジビニルベンゼンからなるポーラ
スポリマビーズを充填した内径３ｍｍφ長さ１ｍのステ
ンレス製カラムを用い、恒温槽７の温度を１２０℃で測
定したときの、増幅器１０の出力を直接記録計に取り出
した結果を第２図に示す。In the configuration described above, a stainless steel column with an inner diameter of 3 mm and a length of 1 m filled with porous polymer beads made of polystyrene divinylbenzene with a mesh size of 60 to 8 degrees was used as the separation column 8, and the temperature of the constant temperature bath 7 was set at 120°C. The output of the amplifier 10 was taken directly to a recorder during measurement, and the results are shown in FIG.
この図かられかるように、１つの試料についての測定は
２分以内で終了する。そこで、マイクロコンピュータ１
３やタイマ（図示せず）の指令により、試料自動注入器
３が切り換わり、次の試料の測定に移るようになってい
る。この操作が繰り返されることにより、はぼ２分間隔
てアンモニアと過酸化水素の濃度を連続して測定するこ
とができる。As can be seen from this figure, measurement for one sample is completed within 2 minutes. Therefore, microcomputer 1
3 or a timer (not shown), the automatic sample injector 3 is switched to proceed to measurement of the next sample. By repeating this operation, the concentrations of ammonia and hydrogen peroxide can be continuously measured at intervals of approximately 2 minutes.
ここで、マイクロコンピュータのソフトウェアを第４図
のフローチャートに従って説明する。前記したように、
ガスクロマトグラムにおいて各成分のピークの出る位置
の間隔は一定であり、酸素、アンモニア、水の順に出る
。スター）（ｔ＝Ｑ）から酸素のピークの出始めるまで
の時間をＬ」、出路るまでの時間をｔ２、同様にアンモ
ニアについての時間をそれぞれｔｓおよびｔ４、水につ
いての時間をそれぞれｔｓおよびｔ６とする。スタート
してからの時間ｔが、ｔｌ＜ ｔ＜ ｔ２となると、カ
スクロマトグラフから酸素の検出成分のデータを受けと
り、このデータにより酸素のピーク面積ＳＯ７を計算す
る。Here, the software of the microcomputer will be explained according to the flowchart of FIG. As mentioned above,
In the gas chromatogram, the intervals between the peaks of each component are constant, and the peaks appear in the order of oxygen, ammonia, and water. The time from star) (t=Q) to the start of the oxygen peak is L'', the time to exit is t2, the time for ammonia is ts and t4, respectively, and the time for water is ts and t6, respectively. shall be. When the time t after the start becomes tl<t<t2, data on the detected oxygen component is received from the gas chromatograph, and the oxygen peak area SO7 is calculated from this data.
さらに時間が経過し、ｔａ＜ｔ＜ｔ４となると、アンモ
ニアの検出成分のデータを受けとり、アンモニアのピー
ク面積５ＮＨ３を計算する。同様に、ｔｓ＜ｔｉｔ６と
なると、水の検出成分のデータを受けとり、水のピーク
面積Ｓｌ １２０を計算する。以上のようにＳＯ２，５
ＮＩ１３、ＳＬ＋２０が全部求められると、あらかじめ
めておいた濃度換算のファクタｆ０２、ｆＮＩ−１３、
ｒｌ］２ｏを用いて、前記（月、（２１式の計算を行い
、アンモニアと過酸化水素の濃度をめる。この計算が終
れば、計算結果の表示を行い、さらに、次の試料の採取
と注入するよう指令を出す。When further time passes and ta<t<t4, data on the detected component of ammonia is received, and the peak area of ammonia, 5NH3, is calculated. Similarly, when ts<tit6, data of the detected component of water is received and the peak area Sl 120 of water is calculated. As above, SO2,5
Once NI13 and SL+20 are all determined, the concentration conversion factors f02, fNI-13, and
rl]2o, calculate the concentration of ammonia and hydrogen peroxide by calculating the concentration of ammonia and hydrogen peroxide using Equation (21).When this calculation is completed, the calculation results are displayed, and the next sample is collected. I give the command to inject it.
」−記の計算をマイクロコンピュータ１３により行わせ
、測定時間ごとにプロットしたグラフを表示１装置１４
に表示させることにより、アンモニア性過酸化水素洗浄
液中のアンモニアと過酸化水素の濃度の時間的変化を正
確に連続的に測定することができる。” - The calculations described below are performed by the microcomputer 13, and a graph plotted for each measurement time is displayed on the display 1 device 14.
By displaying , it is possible to accurately and continuously measure temporal changes in the concentrations of ammonia and hydrogen peroxide in the ammonia-based hydrogen peroxide cleaning solution.
以上説明したように、本発明によれば、アンモニア性過
酸化水素液中のアンモニアと過酸化水素の濃度を同時゛
に簡潔に、しかも連続して測定することが可能となる。As explained above, according to the present invention, it is possible to simultaneously, simply and continuously measure the concentrations of ammonia and hydrogen peroxide in an ammoniacal hydrogen peroxide solution.
また、従来方法では、試料を量的に正確に採取する必要
があるが、試料は６０〜８０℃の高温でかつ気泡を含む
ため正確に採取することができなかったのに対し、本発
明では、溶媒の水も定量するので、試料自動注入器での
試料採取の精度は高い必要はない。さらに、従来法での
測定精度は、室温に冷却する等の操作により精度が悪く
、１０％程度であったが、本発明により、測定精度を１
％程度に向上できる。また、本発明によれば、測定時間
も著しく短縮される。In addition, in the conventional method, it is necessary to collect the sample quantitatively accurately, but the sample cannot be collected accurately because it is at a high temperature of 60 to 80°C and contains air bubbles. Since water as a solvent is also quantified, the accuracy of sample collection using an automatic sample injector is not required to be high. Furthermore, the measurement accuracy with the conventional method was around 10% due to operations such as cooling to room temperature, but with the present invention, the measurement accuracy has been improved to 1%.
It can be improved by about %. Furthermore, according to the present invention, measurement time is also significantly shortened.
第１図は本発明の構成を明示するための全体構成図、第
２図は本発明による酸素、アンモニアおよび水のガスク
ロマトグラムの例、第３図は本発明による装置の構成を
示す構成図、第４図は本発明におけるソフトウェアのフ
ローチャー１・である、符号の説明
１・・・洗浄液槽 ２・・・ポンプ
３・・・試料自動注入器 ４・・・排出パイプ５・・・
気化室 ６・・・銅の網
７・・・恒温槽 ８・・・分離カラム
９・・・熱伝尋度検出器 １０・・・増幅器１１・・・
Ａ／Ｄ 変換器１２−・・インタフェース１３・・・マ
イクロコンピュータ １４・・・表示装置代理人弁理士
中村純之助FIG. 1 is an overall configuration diagram for clearly showing the configuration of the present invention, FIG. 2 is an example of a gas chromatogram of oxygen, ammonia, and water according to the present invention, and FIG. 3 is a configuration diagram showing the configuration of an apparatus according to the present invention. FIG. 4 is a flowchart 1 of the software according to the present invention. Explanation of symbols 1...Cleaning liquid tank 2...Pump 3...Automatic sample injector 4...Discharge pipe 5...
Vaporization chamber 6...Copper mesh 7...Thermostatic chamber 8...Separation column 9...Heat conductivity detector 10...Amplifier 11...
A/D converter 12--Interface 13--Microcomputer 14--Display device attorney Junnosuke Nakamura
Claims (2)
に金属網を保持した気化室に注入して、該金属網の触媒
作用により該試料中の過酸化水素を酸１素と水とに分解
させ、該気化室から出る試料をガスクロマトグラフに導
いて、該試料中のアンモニア、酸素および水の各成分を
検出し、検出結果を基にアンモニアと過酸化水素の濃度
を計算し、計算結果を表示装置により表示し、これらの
操作を次の試料について順次連続して繰り返し行うこと
を特徴とするアンモニア性過酸化水素液中のアンモニア
と過酸化水素の濃度を測定する方法。(1) A sample taken from an ammoniacal hydrogen peroxide solution is injected into a vaporization chamber containing a metal mesh inside, and the hydrogen peroxide in the sample is converted into 1 element of oxygen and water by the catalytic action of the metal mesh. After decomposition, the sample coming out of the vaporization chamber is guided to a gas chromatograph to detect each component of ammonia, oxygen, and water in the sample, and the concentrations of ammonia and hydrogen peroxide are calculated based on the detection results. A method for measuring the concentrations of ammonia and hydrogen peroxide in an ammoniacal hydrogen peroxide solution, characterized by displaying the following on a display device and repeating these operations successively for the next sample.
を自動注入する動作を行う、２本以上のサンプルループ
をもつ自動試料注入器と、該自動試料注入器から試料が
注入され、該試料中の過酸化水素を酸素と水とに分解す
るための触媒となる金属網を内部に保持した気化室と、
該気化室からの試料中のアンモニア、酸素および水の各
成分を検出するガスクロマトグラフと、該ガスクロマト
グラフの検出結果を基にアンモニアと過酸化水素の濃度
を計算する計算機能ブロックと、計算結果を表示する表
示機能ブロックと、計算結果の表示後に前記自動試料注
入器に次の試料採取注入動作をさせる指令を出す指令機
能ブロックとから構成されることを特徴とするアンモニ
ア性過酸化水素液中のアンモニアと過酸化水素の濃度を
測定する装置。(2) An automatic sample injector with two or more sample loops that takes a sample of ammoniacal hydrogen peroxide solution and automatically injects it; A vaporization chamber that holds a metal mesh inside that serves as a catalyst for decomposing the hydrogen peroxide inside into oxygen and water;
a gas chromatograph that detects each component of ammonia, oxygen, and water in the sample from the vaporization chamber; a calculation function block that calculates the concentrations of ammonia and hydrogen peroxide based on the detection results of the gas chromatograph; A display function block that displays a calculation result, and a command function block that issues a command to the automatic sample injector to perform the next sample collection and injection operation after displaying the calculation result. A device that measures the concentration of ammonia and hydrogen peroxide.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11697683A JPS6010170A (en) | 1983-06-30 | 1983-06-30 | Method and apparatus for measuring concentration of ammonia and hydrogen peroxide in ammonia-oriented hydrogen peroxide liquid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11697683A JPS6010170A (en) | 1983-06-30 | 1983-06-30 | Method and apparatus for measuring concentration of ammonia and hydrogen peroxide in ammonia-oriented hydrogen peroxide liquid |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6010170A true JPS6010170A (en) | 1985-01-19 |
| JPH0441306B2 JPH0441306B2 (en) | 1992-07-07 |
Family
ID=14700411
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11697683A Granted JPS6010170A (en) | 1983-06-30 | 1983-06-30 | Method and apparatus for measuring concentration of ammonia and hydrogen peroxide in ammonia-oriented hydrogen peroxide liquid |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6010170A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0310158A (en) * | 1989-06-08 | 1991-01-17 | Kurita Water Ind Ltd | Organic-material analyzing apparatus |
| JP2014035275A (en) * | 2012-08-09 | 2014-02-24 | Shimadzu Corp | Gas chromatograph |
| JP2017151117A (en) * | 2017-04-27 | 2017-08-31 | 株式会社島津製作所 | Gas chromatography apparatus |
| US20220026406A1 (en) * | 2018-12-12 | 2022-01-27 | Shimadzu Corporation | Component analysis system and component detector |
-
1983
- 1983-06-30 JP JP11697683A patent/JPS6010170A/en active Granted
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0310158A (en) * | 1989-06-08 | 1991-01-17 | Kurita Water Ind Ltd | Organic-material analyzing apparatus |
| JP2014035275A (en) * | 2012-08-09 | 2014-02-24 | Shimadzu Corp | Gas chromatograph |
| JP2017151117A (en) * | 2017-04-27 | 2017-08-31 | 株式会社島津製作所 | Gas chromatography apparatus |
| US20220026406A1 (en) * | 2018-12-12 | 2022-01-27 | Shimadzu Corporation | Component analysis system and component detector |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0441306B2 (en) | 1992-07-07 |
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