JPH0226180B2 - - Google Patents
Info
- Publication number
- JPH0226180B2 JPH0226180B2 JP94385A JP94385A JPH0226180B2 JP H0226180 B2 JPH0226180 B2 JP H0226180B2 JP 94385 A JP94385 A JP 94385A JP 94385 A JP94385 A JP 94385A JP H0226180 B2 JPH0226180 B2 JP H0226180B2
- Authority
- JP
- Japan
- Prior art keywords
- gaseous
- light
- window
- peak height
- monitor
- 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.)
- Expired
Links
- 230000003595 spectral effect Effects 0.000 claims description 11
- 238000000034 method Methods 0.000 claims description 9
- 238000010521 absorption reaction Methods 0.000 claims description 6
- 238000011002 quantification Methods 0.000 description 9
- 238000002835 absorbance Methods 0.000 description 7
- 238000001228 spectrum Methods 0.000 description 7
- 238000001514 detection method Methods 0.000 description 6
- 238000000862 absorption spectrum Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 230000035945 sensitivity Effects 0.000 description 3
- 238000000137 annealing Methods 0.000 description 2
- 230000001066 destructive effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 240000006829 Ficus sundaica Species 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 238000001479 atomic absorption spectroscopy Methods 0.000 description 1
- 238000000889 atomisation Methods 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 230000031700 light absorption Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002488 metal-organic chemical vapour deposition Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 238000011896 sensitive detection Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/33—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using ultraviolet light
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/314—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry with comparison of measurements at specific and non-specific wavelengths
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/71—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light thermally excited
- G01N21/74—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light thermally excited using flameless atomising, e.g. graphite furnaces
Landscapes
- Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は新規なＳの定量方法及び該方法を利用
したその場での高感度な検知定量が可能なＳモニ
ターに関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a novel method for quantifying S and an S monitor capable of highly sensitive detection and quantification on the spot using the method.
本発明はＳを用いる半導体製造品及び製造装
置、廃棄物処理装置等、例えばZnS、CdS、
ZnSxSe1-x等の化合物半導体のエピ成長装置
（CVD炉、LPE炉等）、高圧炉HB炉、アニーリン
グ炉、Ｓ圧アニーリング炉、MBE装置、
MOCVD装置等にＳ検出定量高感度モニターと
して利用したり、あるいは、Ｓを含有する合金や
セラミツクス、ガラス等の溶解炉等に利用するこ
とができる。 The present invention relates to semiconductor manufacturing products, manufacturing equipment, waste processing equipment, etc. that use S, such as ZnS, CdS,
Epi growth equipment for compound semiconductors such as ZnSxSe 1-x (CVD furnace, LPE furnace, etc.), high pressure furnace HB furnace, annealing furnace, S pressure annealing furnace, MBE equipment,
It can be used as a high-sensitivity monitor for S detection and quantitative determination in MOCVD equipment, etc., or it can be used in melting furnaces for S-containing alloys, ceramics, glass, etc.
（従来の技術）
従来、Ｓを検出する場合に、非破壊で、系を乱
さず、その場でガス状Ｓを検知定量する方法は殆
んど知られておらず、Ｓの検出は破壊検知が主で
ある。ガス状物質の非破壊検出・定量法として
は、ガスクロマトグラフイーが考えられるが、
測定系内に試料を導くまでに、導入管壁に付着
し、正確な定量ができない、系内からのサンプ
リングを要するため系を乱してしまう、という本
質的な問題点があるため不適であり、実用されて
いない。また、原子吸光分析は、原子状態の試料
について厳密に測定できるが、試料を2000℃以上
の高温状態とする必要があり、原子化温度以下の
検知定量は原理的に不可能であるに加え、用いう
るホロカソードランプがない。(Prior art) Conventionally, when detecting S, there is almost no known method for detecting and quantifying gaseous S on the spot in a non-destructive manner without disturbing the system. is the main thing. Gas chromatography can be considered as a non-destructive detection/quantification method for gaseous substances.
It is unsuitable because it has the inherent problem that it adheres to the wall of the introduction tube before the sample is introduced into the measurement system, making accurate quantification impossible, and that it disturbs the system because it requires sampling from within the system. , has not been put into practice. In addition, atomic absorption spectrometry can accurately measure samples in the atomic state, but it requires the sample to be heated to a high temperature of 2000°C or higher, and detection and quantification at temperatures below the atomization temperature is theoretically impossible. There are no hollow cathode lamps available.
（発明が解決しようとする問題点）
本発明は上記した現状に鑑みてなされたもの
で、非破壊で、系をみださず、その場でガス状Ｓ
の高感度検知・定量が可能な方法及び該方法を利
用した高感度モニターの提供を目的とするもので
ある。(Problems to be Solved by the Invention) The present invention has been made in view of the above-mentioned current situation.
The purpose of the present invention is to provide a method capable of detecting and quantifying with high sensitivity, and a highly sensitive monitor using the method.
（問題点を解決しようとする手段）
すなわち、本発明はガス状Ｓに、波長263nｍ
及び265.5nｍのスペクトル線のうちの１つまたは
２つを、入射し、上記ガス状Ｓによる上記入射ス
ペクトル線の吸収を測定し、各光強度のピーク高
さからＳの検知・定量を行う方法および炉または
ヒータ付容器の光の進行方向に窓部を設け、一方
の窓部に263nｍ及び265.5nｍのスペクトル線のう
ちの１つまたは２つの発光部、他方の窓にはヒー
タ付容器内のガス状Ｓを通過した前記スペクトル
線の光強度のピーク高さからＳを検知定量する受
光、測光部を接続してなる、Ｓモニターである。(Means for solving the problem) That is, the present invention provides gaseous S with a wavelength of 263 nm.
A method in which one or two of the spectral lines of 265.5 nm and 265.5 nm are incident, the absorption of the incident spectral lines by the gaseous S is measured, and S is detected and quantified from the peak height of each light intensity. A window is provided in the direction of light propagation in the furnace or heater-equipped container, and one window has a light-emitting region for one or two of the 263 nm and 265.5 nm spectral lines, and the other window has a light-emitting section for the light in the heater-equipped container. This is an S monitor that is connected to a light receiving and photometering section that detects and quantifies S based on the peak height of the light intensity of the spectral line that has passed through the gaseous S.
以下本発明につき詳細に説明する。 The present invention will be explained in detail below.
本発明者らは、ガス状Ｓ（ガス状ではS2、S4、
S6、S8等になると考えられているが、特定されて
いない。）の吸光スペクトルを詳細に研究の結果、
第１図に示すように、波長263nｍ及び265.5nｍに
吸光のピークを有することを発見した。そしてこ
のようなピークは温度300℃程度のＳの分子の状
況のスペクトルで得られるという知見をも得て、
ガス状Ｓの吸収による263nｍ及び265.5nｍの吸光
ピークを利用することにより、ガス状Ｓを高感度
でかつその場でさえ検出・定量を可能としたもの
である。特に263nｍ及び265.5nｍの両方のスペク
トル線を同時に入射し、分光器で別々に測定して
その平均をとるときには、単一のスペクトル線を
用いる場合より他の物質との分離がより確実とな
り、しかもＳ定量の精度が向上する。 The present inventors have discovered that gaseous S (in gaseous form S 2 , S 4 ,
It is thought that it will be S 6 , S 8, etc., but it has not been identified. ) As a result of detailed research on the absorption spectra of
As shown in FIG. 1, it was discovered that the light absorption peaks were at wavelengths of 263 nm and 265.5 nm. We also obtained the knowledge that such a peak can be obtained in the spectrum of S molecules at a temperature of about 300℃.
By utilizing the absorption peaks of gaseous S at 263 nm and 265.5 nm, it is possible to detect and quantify gaseous S with high sensitivity even on the spot. In particular, when both 263nm and 265.5nm spectral lines are incident simultaneously, measured separately with a spectrometer, and then averaged, separation from other substances is more reliable than when using a single spectral line. The accuracy of S quantification is improved.
本発明は第２図に示すように、炉、ヒータ付セ
ルあるいは筒状１に窓２を取り付け、発光部３に
おいて263nｍまたは265.5nｍのスペクトル線を発
光させ、この光を窓２から入射し、受光部４にお
いて光強度のピーク高さを測定することにより、
炉またはセル中のＳを検知定量するものである。
このＳの検知、定量は、263nｍまたは265.5nｍの
ピーク吸収がＳ濃度に比例することから求める。
ピーク吸収とＳ濃度の関係は
Ｄ＝log１／Ｔ（％） ………(1)
Ｄ∝Ｃ ………(2)
上記(1)、(2)式で表される。ここでＴはピークで
の吸光度（％）、ＣはＳの濃度である。 As shown in FIG. 2, the present invention attaches a window 2 to a furnace, a cell with a heater, or a cylindrical shape 1, emits a spectral line of 263 nm or 265.5 nm in a light emitting part 3, and makes this light enter through the window 2, By measuring the peak height of light intensity in the light receiving section 4,
It detects and quantifies S in a furnace or cell.
The detection and quantification of S is determined from the fact that the peak absorption at 263 nm or 265.5 nm is proportional to the S concentration.
The relationship between peak absorption and S concentration is expressed by the following formulas (1) and (2): D=log1/T (%) (1) D∝C (2) Here, T is the absorbance at the peak (%), and C is the concentration of S.
263nｍ及び265.5nｍのスペクトル発光源として
は、ホロカソードランプを用い、263nｍ及び
265.5nｍのうちの１つまたは２つを中心したフイ
ルターを各々設けたものが使用できる。また該フ
イルターは受光部に設けることもできる。 As the 263nm and 265.5nm spectrum emission source, a hollow cathode lamp is used.
It is possible to use filters each having a filter centered on one or two of 265.5 nm. Further, the filter can also be provided in the light receiving section.
さらに検出結果をコンピユータ処理し、その結
果を表示するようにできる。このようにすれば、
ほぼ実時間でＳを定量検出できるので、その場で
のＳの検知定量とＳの投入量Ｓ圧コントロール等
を制御しうる高感度Ｓモニターを実現できる。 Furthermore, the detection results can be processed by a computer and the results can be displayed. If you do this,
Since it is possible to quantitatively detect S in almost real time, it is possible to realize a highly sensitive S monitor that can detect and quantify S on the spot and control the amount of S input, S pressure, etc.
（実施例）
第３図ａは本発明の実施例で用いた装置の概略
図であつて、１はセル、２は窓、３は発光部、４
は受光部、５は加熱手段をあらわす。なお第３図
ｂはこの装置の温度分布を示すグラフである。(Example) FIG. 3a is a schematic diagram of an apparatus used in an example of the present invention, in which 1 is a cell, 2 is a window, 3 is a light emitting part, and 4 is a schematic diagram of a device used in an example of the present invention.
5 represents a light receiving section, and 5 represents a heating means. Note that FIG. 3b is a graph showing the temperature distribution of this device.
セル１内にＳを置き加熱手段５によりセル１内
の温度を298℃に一定にして保持したときのスペ
クトルを第４図に示す。263nｍ及び265.5nｍを最
大のピークとした吸収スペクトルが明瞭に測定さ
れた。 FIG. 4 shows the spectrum obtained when S was placed in the cell 1 and the temperature inside the cell 1 was kept constant at 298° C. by the heating means 5. An absorption spectrum with maximum peaks at 263 nm and 265.5 nm was clearly measured.
一方、Ｓの投入量と、吸光度の間には、一般的
に第５図に示す関係があることを詳細な実験に確
認した。ここでガス状Ｓが存在するとき検知され
る光強度をＩ、ガス状Ｓがないときの光強度をIo
とすると、吸光度Ｔ（％）は次式(3)で与えられる。 On the other hand, it was confirmed through detailed experiments that there is generally a relationship shown in FIG. 5 between the amount of S added and the absorbance. Here, the light intensity detected when gaseous S exists is I, and the light intensity when gaseous S is absent is Io.
Then, the absorbance T (%) is given by the following equation (3).
Ｔ＝Ｉ／Io×100 ………(3)
したがつて、前記の(1)および(2)式により吸光度
からＳを定量できる。なおＡ点は、温度ｔにおけ
る飽和点をあらわしており、
蒸気圧（logPt（mmHg）＝−6750／ｔ＋11.32）によ
り規定される。 T=I/Io×100 (3) Therefore, S can be quantified from the absorbance using equations (1) and (2) above. Note that point A represents the saturation point at temperature t, and is defined by vapor pressure (logPt (mmHg) = -6750/t + 11.32).
第５図の関係は263nｍと265.5nｍの夫々の吸収
スペクトルについて成立するので、いずれのピー
クの測定によつてもＳ量を求めることができ、特
に両者のスペクトルを用いるときは、精度が向上
し、0.1ppmオーダーまで検出が可能となつた。 The relationship shown in Figure 5 holds true for the absorption spectra of 263 nm and 265.5 nm, so the amount of S can be determined by measuring either peak, and especially when both spectra are used, the accuracy is improved. , it has become possible to detect down to the order of 0.1 ppm.
（発明の効果） 本発明の効果は次のとおりである。(Effect of the invention) The effects of the present invention are as follows.
(1) ガス状Ｓの吸収による波長263nｍ及び265.5n
ｍのスペクトルを利用することにより、ガス状
Ｓの高感度の検知・定量がその場で可能となつ
た。(1) Wavelengths of 263nm and 265.5n due to absorption of gaseous S
By using the spectrum of m, it has become possible to detect and quantify gaseous S with high sensitivity on the spot.
(2) 波長263nｍ及び265.5nｍのスペクトルのうち
の１つまたは２つのピーク高から定量を行なう
ため、Ｓの定量精度が向上する。(2) Since quantification is performed from the peak height of one or two of the spectra of wavelengths 263 nm and 265.5 nm, the accuracy of quantification of S is improved.
(3) 本発明の高感度ＳモニターはＳ量のその場検
知・定量が可能であり、さらにコンピユーター
等演算装置と組合すことにより、各スペクトル
の吸光度から実時間でＳ量を検知定量し、該演
算装置の出力信号によりＳ投入量、Ｓ圧等をそ
の場で制御することができる。(3) The high-sensitivity S monitor of the present invention is capable of on-the-spot detection and quantification of the amount of S, and when combined with a computing device such as a computer, the amount of S can be detected and quantified in real time from the absorbance of each spectrum. The S input amount, S pressure, etc. can be controlled on the spot based on the output signal of the arithmetic unit.
第１図はガス状Ｓの吸光スペクトルである。第
２図は本発明方法及びモニターの概略を示す模式
図である。第３図ａは本発明の実施例で用いた装
置の概略図であり、第３図ｂは第３図ａ装置にお
ける温度分布を示すグラフである。第４図は本発
明の実施例で得られた波長と吸光度の関係を示す
グラフ、第５図はＳ量と吸光度の関係を示すグラ
フである。
FIG. 1 shows the absorption spectrum of gaseous S. FIG. 2 is a schematic diagram showing the outline of the method and monitor of the present invention. FIG. 3a is a schematic diagram of the apparatus used in the embodiment of the present invention, and FIG. 3b is a graph showing the temperature distribution in the apparatus of FIG. 3a. FIG. 4 is a graph showing the relationship between wavelength and absorbance obtained in an example of the present invention, and FIG. 5 is a graph showing the relationship between S amount and absorbance.
Claims (1)
クトル線のうちの１つまたは２つを、入射し、上
記ガス状Ｓによる上記入射スペクトル線の吸収を
測定し、各光強度のピーク高さからＳの検知・定
量を行う方法。 ２ 炉またはヒータ付容器の光の進行方向に窓部
を設け、一方の窓部に波長263nｍ及び265.5nｍの
スペクトル線のうちの１つまたは２つの発光部、
他方の窓にはヒータ付容器内のガス状Ｓを通過し
た前記スペクトル線の光強度のピーク高さからＳ
を検知定量する受光、測光部を接続してなる、Ｓ
モニター。 ３ 光強度のピーク高さからＳを検知・定量し、
それによりＳ投入量コントロール・Ｓ圧コントロ
ールを実時間で制御する特許請求の範囲第２項記
載のＳモニター。 ４ 発光部がホロカソードランプからなる特許請
求の範囲第２項記載のＳモニター。 ５ 発光部または受光部が263nｍおよび265.5nｍ
のうちの１つまたは２つを中心とするフイルタを
有する特許請求の範囲第２項記載のＳモニター。[Claims] 1. One or two of the spectral lines with wavelengths of 263 nm and 265.5 nm are incident on the gaseous S, and the absorption of the incident spectral lines by the gaseous S is measured. A method for detecting and quantifying S based on the intensity peak height. 2 A window is provided in the direction of light propagation of the furnace or container with a heater, and one or two light-emitting parts of the spectral lines with wavelengths of 263 nm and 265.5 nm are provided in one window,
The other window shows S from the peak height of the light intensity of the spectral line that has passed through the gaseous S in the heater-equipped container.
The S
monitor. 3 Detect and quantify S from the peak height of light intensity,
The S monitor according to claim 2, which controls S input amount control and S pressure control in real time. 4. The S monitor according to claim 2, wherein the light emitting section comprises a hollow cathode lamp. 5 Emitting part or light receiving part is 263nm and 265.5nm
3. The S monitor according to claim 2, having a filter centered on one or two of the S monitors.
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP94385A JPS61160043A (en) | 1985-01-09 | 1985-01-09 | Detection and quantitative analysis of sulfur monitor |
| US06/816,843 US4733084A (en) | 1985-01-09 | 1986-01-07 | Method of detection and quantitative determination of sulfur and sulfur monitor using the method |
| DE8686100248T DE3682592D1 (en) | 1985-01-09 | 1986-01-09 | METHOD FOR DETECTING AND QUANTATIVE DETERMINATION OF SULFUR AND SULFUR MONITOR USING THIS METHOD. |
| EP86100248A EP0187675B1 (en) | 1985-01-09 | 1986-01-09 | Method of detection and quantitative determination of sulfur and sulfur monitor using the method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP94385A JPS61160043A (en) | 1985-01-09 | 1985-01-09 | Detection and quantitative analysis of sulfur monitor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61160043A JPS61160043A (en) | 1986-07-19 |
| JPH0226180B2 true JPH0226180B2 (en) | 1990-06-07 |
Family
ID=11487753
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP94385A Granted JPS61160043A (en) | 1985-01-09 | 1985-01-09 | Detection and quantitative analysis of sulfur monitor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61160043A (en) |
-
1985
- 1985-01-09 JP JP94385A patent/JPS61160043A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61160043A (en) | 1986-07-19 |
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