JPH08334461A - Composition measuring method for buffered hydrofluoric acid for semiconductor wafer etching - Google Patents
Composition measuring method for buffered hydrofluoric acid for semiconductor wafer etchingInfo
- Publication number
- JPH08334461A JPH08334461A JP16307595A JP16307595A JPH08334461A JP H08334461 A JPH08334461 A JP H08334461A JP 16307595 A JP16307595 A JP 16307595A JP 16307595 A JP16307595 A JP 16307595A JP H08334461 A JPH08334461 A JP H08334461A
- Authority
- JP
- Japan
- Prior art keywords
- density
- composition
- etching
- hydrofluoric acid
- semiconductor wafer
- 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
Landscapes
- Investigating Or Analysing Materials By Optical Means (AREA)
- Weting (AREA)
Abstract
Description
【０００１】[0001]
【０００２】本発明は、バッファードフッ酸の組成測定
方法に関し、特に、半導体ウエハのエッチング液として
使用されるフッ化水素、フッ化アンモニウム及び水から
なるバッファードフッ酸中のフッ化水素濃度を制御し
て、エッチング工程を管理するに好適な半導体ウエハエ
ッチング用バッファードフッ酸の組成測定方法に関する
ものである。The present invention relates to a method for measuring the composition of buffered hydrofluoric acid, and more particularly, to the concentration of hydrogen fluoride in buffered hydrofluoric acid used as an etching solution for semiconductor wafers, which is composed of hydrogen fluoride, ammonium fluoride and water. The present invention relates to a method for controlling the composition of buffered hydrofluoric acid for semiconductor wafer etching, which is suitable for controlling and controlling the etching process.
【０００３】[0003]
【従来の技術】半導体ウエハのエッチングにおいて、フ
ッ酸、バッファードフッ酸等のフッ化水素系の薬品を使
用する場合、その組成、特にフッ化水素濃度はエッチン
グ速度に大きく影響を及ぼすことから、その濃度を厳し
く管理する必要がある。ところが、エッチング工程にお
けるインライン型の濃度モニターを採用しようとした場
合は、金属、ダスト等による汚染がなく、測定精度、感
度、応答速度等も充足しなければならず、工業的に十分
に満足できるものがなかった。このような理由から、従
来は、濃度の保証された薬品が市販されており、これを
購入して用いるようにしているが、その場合、ウエハ処
理工程によってエッチングプロセスの条件が異なるた
め、濃度の異なる多種類の薬品を保管管理しなければな
らなかった。2. Description of the Related Art In the etching of semiconductor wafers, when a hydrogen fluoride-based chemical such as hydrofluoric acid or buffered hydrofluoric acid is used, its composition, particularly the hydrogen fluoride concentration, greatly affects the etching rate. It is necessary to strictly control the concentration. However, if an in-line type concentration monitor is used in the etching process, there is no contamination by metal, dust, etc., and measurement accuracy, sensitivity, response speed, etc. must be satisfied, which is industrially satisfactory. There was nothing. For this reason, conventionally, chemicals with a guaranteed concentration are commercially available, and they are purchased and used.However, in that case, since the conditions of the etching process differ depending on the wafer processing step, the concentration of I had to store and manage many different types of chemicals.
【０００４】なお、三成分系混合液の分析方法として、
特公平４−６４５７６号には、屈折率と比重とを測定し
これを基にして成分組成を算出する方法が記載されてお
り、実施例として、メタクリロイルオキシエチルトリメ
チルアンモニウムクロライド、アクリルアミド及び水の
三成分系溶液にこの方法が適用されている。また、特開
平６−２７３３０６号には、前記方法の統計的処理の改
良法が記載されており、三成分系溶液において物性に加
成性がある場合、二種の物性を測定し、統計的手法によ
り組成を算出することが可能であることは知られてい
る。しかしながら、どの様な成分の物性に加成性がある
か、また、どの濃度範囲に加成性があるかなどについて
解明されていないことが多く、半導体ウエハエッチング
用のバッファードフッ酸中のフッ化水素濃度についても
同様である。As an analysis method for the ternary mixture,
Japanese Examined Patent Publication No. 4-64576 describes a method of measuring a refractive index and a specific gravity and calculating a component composition on the basis of the refractive index and the specific gravity. As an example, methacryloyloxyethyltrimethylammonium chloride, acrylamide and water This method has been applied to component-based solutions. Further, JP-A-6-273306 describes an improved method of statistical treatment of the above-mentioned method. When the physical properties of a ternary system solution are additive, two types of physical properties are measured and statistically analyzed. It is known that the composition can be calculated by a method. However, it is often not clarified as to what kind of component has the additive property and which concentration range has the additive property. The same applies to the hydrogen chloride concentration.
【０００５】[0005]
【発明が解決しようとする課題】したがって、バッファ
ードフッ酸を使用したシリコン酸化膜のエッチングにお
いては、その液組成がエッチング速度に直ちに影響を及
ぼすためその液組成を容易に把握しエッチング条件にリ
アルタイムに反映したり管理することが切望されている
ものの、未だ十分満足できる方法がなく、前述の如く濃
度保証された多種類の薬品を予め保管して用いなければ
ならならず、ランニングコスト増などが問題となってい
る。なお、バッファードフッ酸によるシリコン酸化膜の
エッチングでは、フッ化アンモニウム濃度１０〜３０ｗ
ｔ％の範囲において、エッチング速度はフッ化水素濃度
に専ら依存し、フッ化アンモニウム濃度の影響は少ない
ことが分かっており、仮に、フッ化水素濃度をリアルタ
イムに知ることが可能になればエッチング管理上、極め
て有用なものとなる。Therefore, in the etching of a silicon oxide film using buffered hydrofluoric acid, the liquid composition immediately affects the etching rate, so that the liquid composition can be easily grasped and the etching conditions can be evaluated in real time. Although there is a long-awaited need to reflect and manage the chemicals, there is still no satisfactory method, and it is necessary to store and use various types of chemicals with guaranteed concentrations as described above, which increases running costs. It's a problem. In the etching of the silicon oxide film with buffered hydrofluoric acid, the ammonium fluoride concentration is 10 to 30 w.
In the range of t%, it is known that the etching rate depends exclusively on the hydrogen fluoride concentration, and the influence of the ammonium fluoride concentration is small. If it becomes possible to know the hydrogen fluoride concentration in real time, etching control will be performed. Above all, it is extremely useful.
【０００６】そこで、本発明者らは、フッ化水素とフッ
化アンモニウムとの混合水溶液の組成測定方法について
種々検討してきた結果、シリコン酸化膜のエッチング剤
として極めて好ましい濃度範囲内において、混合溶液の
密度と比例する物性値及び屈折率から、精度良くその組
成を推算することが可能であることを見出し、本発明を
完成するに至った。[0006] Therefore, as a result of various studies on the method for measuring the composition of a mixed aqueous solution of hydrogen fluoride and ammonium fluoride, the present inventors have found that the mixed solution of a mixed solution is within a concentration range extremely preferable as an etching agent for a silicon oxide film. The inventors have found that the composition can be accurately estimated from the physical property value proportional to the density and the refractive index, and have completed the present invention.
【０００７】[0007]
【課題を解決するための手段】すなわち、本発明に係る
バッファードフッ酸の組成測定方法は、フッ化アンモニ
ウム濃度が１０〜３０ｗｔ％、フッ化水素濃度が０．５
〜１０ｗｔ％である混合水溶液からなる半導体ウエハエ
ッチング用バッファードフッ酸の密度と比例する物性値
（密度自体を含む）及び屈折率を測定し、その値から各
成分の組成分立を下記の連立方程式により算出するもの
である。That is, in the method for measuring the composition of buffered hydrofluoric acid according to the present invention, the ammonium fluoride concentration is 10 to 30 wt% and the hydrogen fluoride concentration is 0.5.
The physical property values (including density itself) and the refractive index that are proportional to the density of the buffered hydrofluoric acid for semiconductor wafer etching consisting of a mixed aqueous solution of 10 wt% are measured, and the compositional separation of each component is determined from the measured values. It is calculated by
【０００８】フッ化水素０．５〜１０ｗｔ％以下、フッ
化アンモニウム濃度１０〜３０ｗｔ％及び水からなる三
成分系溶液においては、密度と比例する物性値（密度自
体を含む）及び屈折率に加成性があり、次の（１ａ），
（１ｂ），（１ｃ）式からなる連立方程式が成立する。 ｎD ＝ａ1ｘ1＋ｂ1ｘ2＋ｃ1ｘ2＋ｃ1ｘ3 ・・・（１ａ） ｄ ＝ａ2ｘ1＋ｂ2ｘ2＋ｃ2ｘ3 ・・・（１ｂ） １ ＝ｘ1＋ｘ2＋ｘ3 ・・・（１ｃ） 但し、式中、ｘ1はフッ化水素の組成分率、ｘ2はフッ化
アンモニウムの組成分率、ｘ3は水の組成分率、ｎDは屈
折率 ａ1、ｂ1、ｃ1はそれぞれの組成分率の屈折率の係数、
ｄは密度と比例する物性値（密度自体も含む）、ａ2、
ｂ2、ｃ2はそれぞれの組成分率の密度と比例する物性値
の係数を表す。なお、本発明において、前記ｄで表され
る物性値としては、密度の他、密度よりも容易に測定可
能なパージ背圧などが挙げられる。In a ternary system solution containing 0.5 to 10 wt% or less of hydrogen fluoride, 10 to 30 wt% of ammonium fluoride concentration, and water, the physical property value (including the density itself) proportional to the density and the refractive index are added. It has the following properties (1a),
A simultaneous equation consisting of equations (1b) and (1c) is established. n D = a 1 x 1 + b 1 x 2 + c 1 x 2 + c 1 x 3 ... (1a) d = a 2 x 1 + b 2 x 2 + c 2 x 3 ... (1b) 1 = x 1 + x 2 + x 3 (1c) where x 1 is the compositional fraction of hydrogen fluoride, x 2 is the compositional fraction of ammonium fluoride, x 3 is the compositional fraction of water, and n D is the refractive index. a 1 , b 1 and c 1 are the coefficients of the refractive index of the respective compositional fractions,
d is a physical property value (including the density itself) proportional to the density, a 2 ,
b 2 and c 2 represent coefficients of physical property values proportional to the densities of the respective composition fractions. In the present invention, examples of the physical property value represented by d include not only the density, but also the purge back pressure that can be measured more easily than the density.
【０００９】前記（１ａ）〜（１ｃ）式からなる第１の
連立方程式から、次の（２ａ），（２ｂ）式からなる第
２の連立方程式が導かれる。 ｎD ＝（ａ1−ｃ1）ｘ1＋（ｂ1−ｃ1）ｘ2＋ｃ1 ・・・（２ａ） ｄ ＝（ａ2−ｃ2）ｘ1＋（ｂ2−ｃ2）ｘ2＋ｃ2 ・・・（２ｂ）From the first simultaneous equations represented by the equations (1a) to (1c), the second simultaneous equations represented by the following equations (2a) and (2b) are derived. n D = (a 1 -c 1 ) x 1 + (b 1 -c 1) x 2 + c 1 ··· (2a) d = (a 2 -c 2) x 1 + (b 2 -c 2) x 2 + c 2 (2b)
【００１０】ここで、前記ａ1、ｂ1、ｃ1及び前記ａ2、
ｂ2、ｃ2は一定の温度で固有の定数であり、組成分率が
既知の多数のサンプルの屈折率ｎD及び密度と比例する
物性値ｄを測定し、これらのデータを前記（１ａ）〜
（１ｃ）式あるいは（２ａ）及び（２ｂ）式に当ては
め、通常の統計的手法で処理することにより、上記の連
立方程式が決まる。したがって、組成分率未知の混合溶
液の屈折ｎD及び密度と比例する物性値ｄを測定し、前
記（１ａ）〜（１ｃ）からなる第１の連立方程式又は前
記（２ａ），（２ｂ）からなる第２の連立方程式を解け
ば各組成分率を算出することができる。その際には、当
然、前記各連立方程式の係数及び定数項の決定にあたっ
て、採用した測定温度と、実際の組成分率測定の際の温
度は一致させる必要がある。Here, the a 1 , b 1 , c 1 and the a 2 ,
b 2 and c 2 are specific constants at a constant temperature, and the physical property value d proportional to the refractive index n D and the density of a large number of samples whose composition fractions are known is measured, and these data are described in (1a) above. ~
The above simultaneous equations are determined by applying the equation (1c) or the equations (2a) and (2b) and processing by the usual statistical method. Therefore, the physical property value d proportional to the refraction n D and the density of the mixed solution of unknown composition fraction is measured, and the first simultaneous equations (1a) to (1c) or the above (2a) and (2b) are used. Each composition fraction can be calculated by solving the following simultaneous equations. In that case, of course, it is necessary to match the measured temperature used in the determination of the coefficient and the constant term of the simultaneous equations with the temperature in the actual composition fraction measurement.
【００１１】本発明において、使用する屈折計にあって
は、フッ酸の屈折率が水よりも小さいため、特殊なプリ
ズムを使用する必要がある。また、プリズムの材質は一
般のソーダガラスではフッ酸に侵されるので、サファイ
ア等のフッ酸耐性の材質を使用する必要がある。このよ
うな屈折計としては、半導体薬品用として実用化されて
いるものを使用できる。密度と比例する物性値ｄとして
は、密度又は比重をフッ酸耐性の浮秤等による比重測定
しても良いが、より簡易にはバッファードフッ酸中の一
定深さで一定圧力の不活性ガス、例えば窒素ガスをパー
ジし、その背圧（パージ背圧）を測定する方法が好まし
い。この種の分析装置としては、半導体製造プロセスに
おいて液面計として実用化されているものが使用可能で
ある。In the refractometer used in the present invention, since the refractive index of hydrofluoric acid is smaller than that of water, it is necessary to use a special prism. Further, since the material of the prism is corroded by hydrofluoric acid in general soda glass, it is necessary to use a hydrofluoric acid resistant material such as sapphire. As such a refractometer, a refractometer practically used for semiconductor chemicals can be used. As the physical property value d proportional to the density, the density or the specific gravity may be measured by the specific gravity using a hydrofluoric acid resistant float balance, but more simply, an inert gas at a constant depth and a constant pressure in the buffered hydrofluoric acid may be used. For example, a method of purging nitrogen gas and measuring the back pressure (purge back pressure) is preferable. As this type of analyzer, an analyzer that has been put into practical use as a liquid level gauge in the semiconductor manufacturing process can be used.
【００１２】[0012]
【実施例】以下、実施例により本発明を更に詳細に説明
する。図１は半導体のエッチング工程におけるエッチン
グ液の組成管理システムを示すブロック図、図２は前記
システムに用いられたパージ背圧測定器の計測原理を示
すブロック図である。The present invention will be described in more detail with reference to the following examples. FIG. 1 is a block diagram showing a composition management system of an etching solution in a semiconductor etching process, and FIG. 2 is a block diagram showing a measuring principle of a purge back pressure measuring instrument used in the system.
【００１３】エッチング槽１内のエッチング液ＥＱは、
図１に示す如くポンプ２、恒温器３を介して循環されて
いる。この循環するエッチング液ＥＱは、恒温器３から
エッチング槽１の間の配管部に接続された屈折計４及び
パージ背圧測定器５により時系列ないしは連続的に屈折
率及びパージ背圧が計測される。The etching solution EQ in the etching tank 1 is
As shown in FIG. 1, it is circulated through a pump 2 and a thermostat 3. The refractive index and the purge back pressure of this circulating etching solution EQ are measured in time series or continuously by a refractometer 4 and a purge back pressure measuring device 5 connected to a pipe section between the thermostat 3 and the etching tank 1. It
【００１４】前記パージ背圧測定器５は、図２に示す如
く窒素ガスが使用されており、窒素ガスがガス供給部６
の流量調整バルブで流量を制御されてフィルター７から
検出パイプ部８を経由して、測定用として導出されたエ
ッチング液部９の一定液深にパージされる。検出パイプ
部８は液面計ないしはパージ背圧検知計１０に接続され
ており、パージ背圧が計測される。The purge back pressure measuring device 5 uses nitrogen gas as shown in FIG.
The flow rate is controlled by the flow rate control valve of No. 3, and the etching liquid unit 9 is purged to a constant liquid depth from the filter 7 via the detection pipe unit 8 for measurement. The detection pipe unit 8 is connected to a liquid level gauge or a purge back pressure detector 10 to measure the purge back pressure.
【００１５】そして、屈折計４及びパージ背圧測定器５
により計測された各計測値は、電流信号に変換されてイ
ンターフェイス１１を介してコンピューターシステム１
２に入力される。コンピューターシステム１２には、予
め係数及び定数項を定めた前記式（２ａ），（２ｂ）か
らなる第２の連立方程式に基づく組成分率推算式がプロ
グラムされており、これによって入力値が処理されエッ
チング液の組成分率が演算されて表示部（図示しない）
に表示されたり、プリンターされる。Then, the refractometer 4 and the purge back pressure measuring device 5
Each measurement value measured by the computer system 1 is converted into a current signal via the interface 11
Entered in 2. The computer system 12 is programmed with a composition fraction estimation formula based on the second simultaneous equation consisting of the formulas (2a) and (2b) in which the coefficient and the constant term are determined in advance, and the input value is processed by this. The composition ratio of the etching solution is calculated and displayed (not shown)
Is displayed on the printer.
【００１６】更に、図１の組成管理システムでは、調整
用のフッ酸供給部１３とフッ化アンモニウム水溶液供給
部１４とが設けられ、前記コンピューターシステム７か
らの指令により各供給部１３，１４の流量調整バルブ
（図示しない）が作動制御されて、エッチング槽１内の
エッチング液ＥＱについてその組成が一定に保たれるよ
うになっている。Further, in the composition management system of FIG. 1, a hydrofluoric acid supply unit 13 for adjustment and an ammonium fluoride aqueous solution supply unit 14 are provided, and the flow rate of each supply unit 13, 14 is commanded by the computer system 7. The adjustment valve (not shown) is controlled to keep the composition of the etching solution EQ in the etching tank 1 constant.
【００１７】（実施例１）４９．９ｗｔ％のフッ酸、４
０．４ｗｔ％のフッ化アンモニウム水溶液及び純粋を混
合し、フッ化水素濃度１〜６ｗｔ％、フッ化アンモニウ
ム濃度１０〜３０ｗｔ％の範囲で５４種（フッ化水素
１、２、３、４、５、６ｗｔ％、フッ化アンモニウム１
０、１２、１４、１６、１８、２０、２２、２４、２６
ｗｔ％）の組成のバッファードフッ酸を調整し、液温２
０℃におけるそれぞれの屈折率とパージ背圧（混合液中
の一定の深さで窒素ガスをパージし、その背圧ｍｍＨ2
Ｏ）を測定し、重回帰分析の手法により、このデータを
前記（２ａ），（２ｂ）からなる第２の連立方程式に当
てはめて処理し、下記の推算式（３ａ），（３ｂ）を得
た。 ｎD ＝0.00074ｘ1−0.00151ｘ2＋1.33767 ・・・（３ａ） ｄ ＝1.56250ｘ1＋0.87937ｘ2＋490.22315 ・・・（３ｂ） この推算式（３ａ），（３ｂ）の精度を調べるため、屈
折率の実側値ｎDと、密度と比例する物性値ｄ（パージ
背圧ｍｍＨ2Ｏ）の実測値とを推算式（３ａ），（３
ｂ）に代入して組成分率の推算値を求めた。その結果
は、下記の通り、誤差の相対標準偏差を求めたところ、
フッ化アンモニウムで０．０１９、フッ化水素で０．１
１３となり、実用的に十分な精度であることが確認され
た。 相対誤差ＣＶ＝（設定値−推算値）／設定値 相対標準偏差＝｛Σ（ＣＶ）2／（ｎ−１）｝1/2 但し、 ｎ：サンプル数(Example 1) 49.9 wt% hydrofluoric acid, 4
An ammonium fluoride aqueous solution of 0.4 wt% and pure water are mixed, and 54 kinds (hydrogen fluoride 1, 2, 3, 4, 5) of hydrogen fluoride concentration of 1 to 6 wt% and ammonium fluoride concentration of 10 to 30 wt% are mixed. , 6 wt%, ammonium fluoride 1
0, 12, 14, 16, 18, 20, 22, 24, 26
wt%) buffered hydrofluoric acid with a composition of 2%
Refractive index and purge back pressure at 0 ° C. (nitrogen gas was purged at a constant depth in the mixed solution, and the back pressure mmH 2
O) was measured, and this data was applied to the second simultaneous equation consisting of (2a) and (2b) and processed by the method of multiple regression analysis to obtain the following estimation formulas (3a) and (3b). It was n D = 0.00074x 1 -0.00151x 2 +1.33767 (3a) d = 1.56250x 1 + 0.87937x 2 +490.22315 (3b) The accuracy of these estimation formulas (3a) and (3b) In order to investigate, the real side value n D of the refractive index and the measured value of the physical property value d (purge back pressure mmH 2 O) proportional to the density are estimated by the formulas (3a), (3
By substituting it in b), the estimated value of the compositional fraction was obtained. As a result, when the relative standard deviation of the error was calculated as follows,
0.019 for ammonium fluoride and 0.1 for hydrogen fluoride
It was 13 and it was confirmed that the accuracy was practically sufficient. Relative error CV = (set value-estimated value) / set value Relative standard deviation = {Σ (CV) 2 / (n-1)} 1/2 where n: number of samples
【００１８】（参考比較例）フッ化アンモニウム０〜４
０ｗｔ％、フッ化水素０〜６ｗｔ％の範囲の１３６種の
サンプルを用い、実施例と同様に推算式を求め、誤算の
相対標準偏差を計算したところ、フッ化アンモニウムで
０．５８４、フッ化水素で０．２０５と、実施例に比べ
大きな誤差となった。(Reference Comparative Example) Ammonium Fluoride 0-4
When 136 kinds of samples in the range of 0 wt% and hydrogen fluoride 0 to 6 wt% were used, an estimation formula was obtained in the same manner as in the example, and the relative standard deviation of miscalculation was calculated. The error was 0.205 for hydrogen, which was a large error compared to the example.
【００１９】[0019]
【発明の効果】以上の本発明によれば、バッファードフ
ッ酸の組成分率をリアルタイムで高性能に測定できる。
これにより、従来のように多種の濃度保証された薬液を
保管する必要がなくなり、エッチング工程をより正確か
つ容易に管理することが可能となる。As described above, according to the present invention, the compositional fraction of buffered hydrofluoric acid can be measured in real time with high performance.
As a result, it is not necessary to store various kinds of chemical solutions whose concentrations are guaranteed as in the conventional case, and the etching process can be managed more accurately and easily.
【図１】本発明を適用した半導体のエッチング工程にお
けるエッチング液の組成管理システムを示すブロック図
である。FIG. 1 is a block diagram showing a composition management system of an etching solution in a semiconductor etching process to which the present invention is applied.
【図２】前記組成管理システム中の背圧測定器を示すブ
ロック図である。FIG. 2 is a block diagram showing a back pressure measuring device in the composition management system.
１ エッチング槽 ４ 屈折計 ５ 背圧測定器 １２ コンピュータシステム 1 Etching tank 4 Refractometer 5 Back pressure measuring device 12 Computer system
Claims (3)
ｔ％、フッ化水素濃度が０．５〜１０ｗｔ％である混合
水溶液からなる半導体ウエハエッチング用バッファード
フッ酸の密度と比例する物性値及び屈折率を測定し、下
記の（１ａ），（１ｂ），（１ｃ）式からなる連立方程
式に基づき各成分の組成分率を算出する半導体ウエハエ
ッチング用バッファードフッ酸の組成測定方法。 ｎD ＝ａ1ｘ1＋ｂ1ｘ2＋ｃ1ｘ3 ・・・・（１ａ） ｄ ＝ａ2ｘ1＋ｂ2ｘ2＋ｃ2ｘ3 ・・・・（１ｂ） １ ＝ｘ1＋ｘ2＋ｘ3 ・・・・（１ｃ） 但し、式中、 ｘ1はフッ化水素の組成分率、 ｘ2はフッ化アンモニウムの組成分率、 ｘ3は水の組成分率、 ｎDは屈折率 ａ1、ｂ1、ｃ1はそれぞれの組成分率の屈折率の係数、 ｄは密度と比例する物性値、 ａ2、ｂ2、ｃ2はそれぞれの組成分率の密度と比例する
物性値の係数を表す。1. The ammonium fluoride concentration is 10 to 30 w.
A physical property value and a refractive index which are proportional to the density of the buffered hydrofluoric acid for etching a semiconductor wafer made of a mixed aqueous solution of t% and hydrogen fluoride concentration of 0.5 to 10 wt% are measured, and the following (1a), (1b) ), A method for measuring the composition of buffered hydrofluoric acid for semiconductor wafer etching, which calculates the composition fraction of each component based on the simultaneous equations consisting of the equations (1c). n D = a 1 x 1 + b 1 x 2 + c 1 x 3 ... (1a) d = a 2 x 1 + b 2 x 2 + c 2 x 3 ... (1b) 1 = x 1 + x 2 + x 3 ... (1c) where x 1 is the compositional fraction of hydrogen fluoride, x 2 is the compositional fraction of ammonium fluoride, x 3 is the compositional fraction of water, and n D is the refractive index a 1 , b 1 and c 1 are coefficients of refractive index of respective composition fractions, d is a physical property value proportional to density, a 2 , b 2 and c 2 are physical property values proportional to density of respective composition fractions. Represents a coefficient.
ァードフッ酸中の定深さで一定圧力の窒素ガスをパージ
した際のパージ背圧である請求項１記載の半導体ウエハ
エッチング用バッファードフッ酸の組成測定方法。2. The semiconductor wafer etching buffer according to claim 1, wherein the physical property value d proportional to the density is a purge back pressure when nitrogen gas having a constant depth and a constant pressure in the buffered hydrofluoric acid is purged. A method for measuring the composition of dehydrofluoric acid.
体である請求項１記載の半導体ウエハエッチング用バッ
ファードフッ酸の組成測定方法。3. The method for measuring the composition of a buffered hydrofluoric acid for etching a semiconductor wafer according to claim 1, wherein the physical property value d proportional to the density is the density itself.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16307595A JPH08334461A (en) | 1995-06-07 | 1995-06-07 | Composition measuring method for buffered hydrofluoric acid for semiconductor wafer etching |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16307595A JPH08334461A (en) | 1995-06-07 | 1995-06-07 | Composition measuring method for buffered hydrofluoric acid for semiconductor wafer etching |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH08334461A true JPH08334461A (en) | 1996-12-17 |
Family
ID=15766713
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16307595A Pending JPH08334461A (en) | 1995-06-07 | 1995-06-07 | Composition measuring method for buffered hydrofluoric acid for semiconductor wafer etching |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH08334461A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1172844A2 (en) * | 2000-07-14 | 2002-01-16 | Sony Corporation | Substrate cleaning method and substrate cleaning apparatus |
| US6799589B2 (en) * | 2000-11-08 | 2004-10-05 | Sony Corporation | Method and apparatus for wet-cleaning substrate |
| US10139363B2 (en) | 2015-08-28 | 2018-11-27 | Horiba, Ltd. | BHF solution concentration measurement device and BHF solution concentration measurement method |
-
1995
- 1995-06-07 JP JP16307595A patent/JPH08334461A/en active Pending
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1172844A2 (en) * | 2000-07-14 | 2002-01-16 | Sony Corporation | Substrate cleaning method and substrate cleaning apparatus |
| EP1172844A3 (en) * | 2000-07-14 | 2005-12-14 | Sony Corporation | Substrate cleaning method and substrate cleaning apparatus |
| US7255749B2 (en) | 2000-07-14 | 2007-08-14 | Sony Corporation | Substrate cleaning method and substrate cleaning apparatus |
| KR100870255B1 (en) * | 2000-07-14 | 2008-11-25 | 소니 가부시끼 가이샤 | Substrate cleaning method and substrate cleaning apparatus |
| US6799589B2 (en) * | 2000-11-08 | 2004-10-05 | Sony Corporation | Method and apparatus for wet-cleaning substrate |
| US6938626B2 (en) | 2000-11-08 | 2005-09-06 | Sony Corporation | Method and apparatus for wet-cleaning substrate |
| US10139363B2 (en) | 2015-08-28 | 2018-11-27 | Horiba, Ltd. | BHF solution concentration measurement device and BHF solution concentration measurement method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Pate et al. | Chemical metrology methods for CMP quality | |
| US5439569A (en) | Concentration measurement and control of hydrogen peroxide and acid/base component in a semiconductor bath | |
| US5364510A (en) | Scheme for bath chemistry measurement and control for improved semiconductor wet processing | |
| KR100772802B1 (en) | Method for measuring fluid component concentrations and apparatus therefor | |
| Garrett et al. | A reexamination of the measurement of dynamic surface tensions using the maximum bubble pressure method | |
| EP1286239A2 (en) | Method and system for controlling the concentration of a component in a composition with absorption spectroscopy | |
| JP2016006434A (en) | Analysis of silicon concentration in etching agent solution | |
| CN109791099B (en) | Concentration detection method and pressure type flow rate control device | |
| US6171975B1 (en) | Wet-chemical treatment method, treatment method of semiconductor substrate, and manufacturing method of semiconductor device | |
| KR102580098B1 (en) | Selective monitoring of multiple silicon compounds | |
| US20020157448A1 (en) | Flowmeter calibration apparatus | |
| US5175502A (en) | Method and apparatus for determining acid concentration | |
| JPH08334461A (en) | Composition measuring method for buffered hydrofluoric acid for semiconductor wafer etching | |
| JPH05102122A (en) | Etching method | |
| Vargas-Lara et al. | Dimensional reduction of duplex DNA under confinement to nanofluidic slits | |
| US6238589B1 (en) | Methods for monitoring components in the TiW etching bath used in the fabrication of C4s | |
| WO2023157421A1 (en) | Electrolyte concentration measuring device and method for obtaining selectivity coefficient | |
| JPS628040A (en) | Washing apparatus | |
| US20020146348A1 (en) | Universal pickle liquor acid analyzer | |
| JPH04278529A (en) | Silicon wafer cleaning equipment | |
| JP2010261895A (en) | Method and apparatus for measuring concentration of trace constituent in solution | |
| US7306765B2 (en) | Apparatus and method for chemical analysis | |
| US5286358A (en) | Method of analyzing the complexing power of a pickling liquor | |
| Moon et al. | Vapor-liquid equilibria for the ethyl methyl ketone+ water system with limited miscibility | |
| US5146413A (en) | Method for the determinate evaluation of a chemistry analyzer's combined diluting and analyzing systems |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20040701 |