JP2006201016A - Method for measuring film thickness - Google Patents

Method for measuring film thickness Download PDF

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JP2006201016A
JP2006201016A JP2005012479A JP2005012479A JP2006201016A JP 2006201016 A JP2006201016 A JP 2006201016A JP 2005012479 A JP2005012479 A JP 2005012479A JP 2005012479 A JP2005012479 A JP 2005012479A JP 2006201016 A JP2006201016 A JP 2006201016A
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film thickness
thickness value
film
objective lens
peak valley
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Yutaka Fujiwara
豊 藤原
Hideki Nakakuki
秀樹 中久木
Masashi Kubota
正志 久保田
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Toppan Inc
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Toppan Printing Co Ltd
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Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for measuring film thickness capable of finding a film thickness value with precision equivalent to that in precise perpendicular incidence, from the maximum wavelength and the minimum wavelength of an acquired spectral reflectance data, even when using illumination light converged by an objective lens with a large numerical aperture. <P>SOLUTION: A film thickness value calculated by a peak valley method is corrected to bring the true film thickness value in assumption that the film thickness value calculated by the peak valley method is a film thickness value including an influence of diagonal incidence of the illumination light in response to the numerical aperture of the objective lens. The correction is carried out by multiplying the film thickness value calculated by the peak valley method with θ<SB>2</SB>/sinθ<SB>2</SB>(≥1) as a correction factor. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明は、液晶表示装置用のガラス基板などの基板上に形成された薄膜の膜厚値を非接触で求める膜厚測定方法に関する。   The present invention relates to a film thickness measurement method for obtaining a film thickness value of a thin film formed on a substrate such as a glass substrate for a liquid crystal display device in a non-contact manner.

分光干渉式による非接触膜厚測定は、照明光を膜に垂直に照射し、膜表面からの反射光と、膜と基板との境界面からの反射光との位相差により生じる干渉現象を利用したものである。位相差は膜表面からの反射光と、膜と基板との境界面からの反射光との光路差に依存し、光路差は膜の物理膜厚と、膜の屈折率とに依存する。したがって、膜の屈折率が既知であれば、物理膜厚を算出することができる。   Non-contact film thickness measurement using the spectral interference method irradiates illumination light perpendicularly to the film and uses the interference phenomenon caused by the phase difference between the reflected light from the film surface and the reflected light from the interface between the film and the substrate. It is a thing. The phase difference depends on the optical path difference between the reflected light from the film surface and the reflected light from the boundary surface between the film and the substrate, and the optical path difference depends on the physical film thickness of the film and the refractive index of the film. Therefore, if the refractive index of the film is known, the physical film thickness can be calculated.

近年、液晶表示装置用部材、半導体素子の製造工程等において、被測定部分の微小化が望まれている。例えば、液晶表示装置の部材であるカラーフィルタのパターニングされたある特定位置における膜厚値を非破壊・非接触で測定する要請があるが、そのためには、開口数の大きい対物レンズを光学系に組み込む必要がある。   In recent years, miniaturization of a portion to be measured has been desired in a manufacturing process of a member for a liquid crystal display device, a semiconductor element, and the like. For example, there is a demand for non-destructive and non-contact measurement of a film thickness value at a specific position where a color filter, which is a member of a liquid crystal display device, is patterned. For this purpose, an objective lens having a large numerical aperture is used as an optical system. Must be included.

ところが、この場合、試料に照射する光が対物レンズを介するために、照明光の入射角度は０から対物レンズの開口数に応じた角度までの範囲に及ぶことになる。これは、膜表面からの反射光と、膜と基板との境界面からの反射光との位相差を発生させる光路差が、厳密な垂直入射時とは異なることを意味している。
そのため、比較的開口数の大きい対物レンズを使用する場合は、例えば、特開２００２−３１８１０６号公報、特開２００３−４２７２２号公報に記載の膜厚測定方法（以下「従来方法」と記す）を適用しても、膜厚値を精度よく求めることができないという問題があった。 However, in this case, since the light applied to the sample passes through the objective lens, the incident angle of the illumination light ranges from 0 to an angle corresponding to the numerical aperture of the objective lens. This means that the optical path difference that generates the phase difference between the reflected light from the film surface and the reflected light from the boundary surface between the film and the substrate is different from that at the time of strict vertical incidence.
Therefore, when an objective lens having a relatively large numerical aperture is used, for example, the film thickness measurement method described in JP 2002-318106 A and JP 2003-42722 A (hereinafter referred to as “conventional method”) is used. Even when applied, there is a problem that the film thickness value cannot be obtained with high accuracy.

そこで、膜の一部を鋭利な刃物で掻き取って膜表面と基板表面との段差を作り、触針式の段差計による測定が行われているが、このような方法は測定のための準備が煩わしく、測定時間も掛かるうえに被測定物を破壊する破壊計測であるため、ロスの削減を期待することはできない。
特開２００２−３１８１０６号公報 特開２００３−４２７２２号公報 特開平６−２４９６２０号公報 Therefore, a part of the film is scraped off with a sharp blade to create a step between the film surface and the substrate surface, and measurement using a stylus type step gauge is performed. This is a destructive measurement that destroys the object to be measured and takes a long time to measure, so it cannot be expected to reduce the loss.
JP 2002-318106 A JP 2003-42722 A JP-A-6-249620

本発明は上記の問題に鑑みなされたものであり、その課題とするところは、開口数の大きい対物レンズにより収束させた照明光を使用しても、取得した分光反射率データの極大波長、極小波長から、厳密な垂直入射時と同等な精度で膜厚値を求める膜厚測定方法を提供することにある。   The present invention has been made in view of the above problems, and the problem is that the maximum wavelength and the minimum wavelength of the acquired spectral reflectance data are obtained even when illumination light converged by an objective lens having a large numerical aperture is used. It is an object of the present invention to provide a film thickness measuring method for obtaining a film thickness value from a wavelength with an accuracy equivalent to that at the time of strict vertical incidence.

本発明は、基板上に形成された薄膜の膜表面の微小領域部分に、対物レンズにより収束した照明光をその光軸が膜表面に対して垂直になるように照射し、その微小領域部分から反射された光を分光して取得される分光反射率データの極大波長、極小波長から前記薄膜
の膜厚値を求めるピークバレー法による膜厚測定方法において、前記ピークバレー法により算出した膜厚値は、対物レンズの開口数に応じた照明光の斜入射の影響を含む膜厚値であるという仮定のもとに、前記ピークバレー法により算出した膜厚値を補正して真の膜厚値とすることを特徴とする膜厚測定方法である。 In the present invention, illumination light converged by an objective lens is irradiated onto a minute area portion of a thin film surface formed on a substrate so that its optical axis is perpendicular to the film surface. The film thickness value calculated by the peak valley method in the film thickness measuring method by the peak valley method for obtaining the film thickness value of the thin film from the maximum wavelength and the minimum wavelength of the spectral reflectance data obtained by spectrally dividing the reflected light. Is a true film thickness value by correcting the film thickness value calculated by the peak valley method under the assumption that the film thickness value includes the influence of oblique incidence of illumination light according to the numerical aperture of the objective lens. It is the film thickness measuring method characterized by these.

また、本発明は、上記発明による膜厚測定方法において、前記補正が、ピークバレー法により算出した膜厚値に、θ2／ｓｉｎθ2（≧１）を補正係数として掛ける補正であることを特徴とする膜厚測定方法である。 In the film thickness measuring method according to the present invention, the correction is a correction in which the film thickness value calculated by the peak valley method is multiplied by θ 2 / sin θ 2 (≧ 1) as a correction coefficient. It is a film thickness measuring method.

本発明は、ピークバレー法により算出した膜厚値は、対物レンズの開口数に応じた照明光の斜入射の影響を含む膜厚値であるという仮定のもとに、ピークバレー法により算出した膜厚値を補正して真の膜厚値とするので、対物レンズにより収束させた照明光を使用した場合においても、真の膜厚値に近い値を得ることができる膜厚測定方法となる。   In the present invention, the film thickness value calculated by the peak valley method is calculated by the peak valley method under the assumption that the film thickness value includes the influence of oblique incidence of illumination light according to the numerical aperture of the objective lens. Since the film thickness value is corrected to obtain a true film thickness value, a film thickness measurement method capable of obtaining a value close to the true film thickness value even when illumination light converged by an objective lens is used. .

以下、本発明の実施の形態を詳細に説明する。
図１は、同一試料の特定位置に、開口数の異なる複数種類の対物レンズを介して照明光を照射したときの分光反射率データを示す説明図である。図１から明らかなように、対物レンズの開口数が大きいほど、分光反射スペクトルの極大・極小位置は短波長側にシフトしていることがわかる。 Hereinafter, embodiments of the present invention will be described in detail.
FIG. 1 is an explanatory diagram showing spectral reflectance data when a specific position of the same sample is irradiated with illumination light through a plurality of types of objective lenses having different numerical apertures. As is clear from FIG. 1, it can be seen that the maximum and minimum positions of the spectral reflection spectrum shift to the short wavelength side as the numerical aperture of the objective lens increases.

以下、この結果を現象論的に説明するため、膜表面ａからの反射光Ｒ1と、膜と基板との境界面ｂからの反射光Ｒ2との位相差を発生させる光路差について、照明光Ｉが、Ａ）垂直入射される場合と、Ｂ）斜入射される場合とにわけて説明する。 Hereinafter, in order to explain this result phenomenologically, an optical path difference that generates a phase difference between the reflected light R 1 from the film surface a and the reflected light R 2 from the boundary surface b between the film and the substrate will be described. The light I will be described separately for A) normal incidence and B) oblique incidence.

Ａ）垂直入射（図２参照）
空気、膜、基板の屈折率をそれぞれｎ1、ｎ2、ｎ3（ただし、ｎ1＜ｎ2＞ｎ3）とすると、反射光Ｒ1と反射光Ｒ2との光路差は２ｎ2ｄであり、ｎ1＜ｎ2＞ｎ3なので、反射光Ｒ1および反射光Ｒ2の位相は入射光の位相に比べてπだけ変化する。したがって、極小波長をλ1、極大波長をλ2、干渉次数をｍ（整数）として、下記に示す数式（１）、数式（２）が成り立つ。 A) Normal incidence (see Fig. 2)
When the refractive indexes of air, film, and substrate are n 1 , n 2 , and n 3 (where n 1 <n 2 > n 3 ), the optical path difference between the reflected light R 1 and the reflected light R 2 is 2n 2 d. Since n 1 <n 2 > n 3 , the phases of the reflected light R 1 and the reflected light R 2 change by π compared to the phase of the incident light. Therefore, the following formulas (1) and (2) are established where the minimum wavelength is λ 1 , the maximum wavelength is λ 2 , and the interference order is m (integer).

ここで、ｎ2（λ1）、ｎ2（λ2）は、膜の屈折率ｎ2の波長分散を考慮したもので、膜の屈折率ｎ2が波長λの関数であることを表している。数式（１）、数式（２）からｍを消去して数式（３）を得る。 Here, n 2 (λ 1), n 2 (λ 2) is obtained by taking into account the wavelength dispersion of the refractive index n 2 of the film, it indicates that the refractive index n 2 of the film is a function of the wavelength lambda Yes. The mathematical expression (3) is obtained by eliminating m from the mathematical expressions (1) and (2).

したがって、分光反射スペクトルから極小波長λ1、極大波長λ2を求め、干渉次数ｍと膜の屈折率ｎ2を与えれば膜厚ｄを算出することができる。 Therefore, if the minimum wavelength λ 1 and the maximum wavelength λ 2 are obtained from the spectral reflection spectrum and given the interference order m and the refractive index n 2 of the film, the film thickness d can be calculated.

Ｂ）斜入射（図３参照）
膜表面ａ、基板表面ｂにおける入射角をそれぞれθ1、θ2（０≦θ1≦（π／２）、０≦θ2≦（π／２））とすると、反射光Ｒ1と反射光Ｒ2との光路差は２ｎ2ｄｃоｓθ2であるから、下記に示す数式（４）、数式（５）が成り立つ。 B) Oblique incidence (see Fig. 3)
When the incident angles on the film surface a and the substrate surface b are θ 1 and θ 2 (0 ≦ θ 1 ≦ (π / 2), 0 ≦ θ 2 ≦ (π / 2)), respectively, the reflected light R 1 and the reflected light Since the optical path difference with R 2 is 2n 2 dc θsθ 2 , the following formulas (4) and (5) hold.

数式（４）、数式（５）と、数式（１）、数式（２）を見比べてみると、数式（４）、数式（５）から求まるλ1、λ2は、数式（１）、数式（２）から求まるλ1、λ2にｃоｓ
θ2（≦１）を掛けた値となることがわかる。つまり、θ2が大きくなるほど、分光反射スペクトルの極大位置、極小位置は短波長側にシフトすることになる。 Comparing Formula (4) and Formula (5) with Formula (1) and Formula (2), λ 1 and λ 2 obtained from Formula (4) and Formula (5) are expressed by Formula (1) and Formula C s in λ 1 and λ 2 obtained from (2)
It can be seen that the value is multiplied by θ 2 (≦ 1). That is, as θ 2 increases, the maximum position and the minimum position of the spectral reflection spectrum shift to the short wavelength side.

数式（４）、数式（５）からｍを消去して数式（６）を得る。   M is deleted from Equations (4) and (5) to obtain Equation (6).

数式（６）は、垂直入射時と同様にして分光反射スペクトルから極小波長λ1、極大波長λ2を求め、干渉次数ｍと膜の屈折率ｎ2を与えることによって求まる物理量は、膜厚値にｃоｓθ2（≦１）を掛けた値であり、実際の膜厚値よりも小さくなることを示している。つまり、θ2が大きくなるほど、算出される物理量は、実際の膜厚値よりも小さくなる。 Equation (6) is obtained by obtaining the minimum wavelength λ 1 and the maximum wavelength λ 2 from the spectral reflection spectrum in the same manner as at the time of vertical incidence, and by giving the interference order m and the refractive index n 2 of the film, the physical quantity obtained is the film thickness value. Is multiplied by c ｃsθ 2 (≦ 1), indicating that it is smaller than the actual film thickness value. That is, as θ 2 increases, the calculated physical quantity becomes smaller than the actual film thickness value.

以上が、対物レンズの開口数が大きくなるほど、分光反射スペクトルの極大位置、極小位置が短波長側にシフトしてしまうこと、および、算出される膜厚値が実際の値よりも小さくなる理由についての現象論的な説明である。   As described above, as the numerical aperture of the objective lens increases, the maximum position and the minimum position of the spectral reflection spectrum shift to the short wavelength side, and the reason why the calculated film thickness value is smaller than the actual value. This is a phenomenological explanation.

続いて、開口数ＮＡの対物レンズを使用した場合における膜表面ａからの反射光と、膜と基板との境界面ｂからの反射光との光路差について、図４を用いて定量的に説明する。まず、対物レンズＬの開口数ＮＡと、膜表面ａにおける入射角θ1との間には、下記に示す数式（７）の関係がある。 Subsequently, the optical path difference between the reflected light from the film surface a and the reflected light from the boundary surface b between the film and the substrate when an objective lens having a numerical aperture NA is used will be quantitatively described with reference to FIG. To do. First, the following numerical formula (7) exists between the numerical aperture NA of the objective lens L and the incident angle θ 1 on the film surface a.

また、数式（８）に示すスネルの法則と数式（７）から、数式（９）が得られる。 Further, the formula (9) is obtained from the Snell's law and the formula (7) shown in the formula (8).

つまり、開口数ＮＡの対物レンズを使用した場合、膜を透過した照明光は、−θ2≦θ≦θ2の範囲で基板面に入射することになる。よって、この場合の光路差は、斜入射時（図３）における光路差２ｎ2ｄｃоｓθを、−θ2≦θ≦θ2の範囲で積分して平均をとった量として近似することができる。 That is, when an objective lens having a numerical aperture NA is used, the illumination light transmitted through the film is incident on the substrate surface in the range of −θ 2 ≦ θ ≦ θ 2 . Therefore, the optical path difference in this case can be approximated as an amount obtained by integrating the optical path difference 2n 2 dc оsθ at the time of oblique incidence (FIG. 3) in the range of −θ 2 ≦ θ ≦ θ 2 .

そこで、図３における反射光Ｒ1と反射光Ｒ2との光路差に対応する量として、平均光路差Δという概念を導入すると、平均光路差Δは数式（１０）のように定義することができる。 Therefore, when the concept of the average optical path difference Δ is introduced as an amount corresponding to the optical path difference between the reflected light R 1 and the reflected light R 2 in FIG. 3, the average optical path difference Δ can be defined as in Expression (10). it can.

すると、垂直入射時の数式（１）〜数式（３）、あるいは、斜入射時の数式（４）〜数式（６）に対応する式は、下記に示す数式（１１）〜数式（１３）で表すことができる。 Then, formulas (1) to (3) at the time of vertical incidence or formulas (4) to (6) at the time of oblique incidence are formulas (11) to (13) shown below. Can be represented.

したがって、分光反射スペクトルから極小波長λ1、極大波長λ2を求め、干渉次数ｍと膜の屈折率ｎ2を与えることによって求まる物理量は、膜厚値にｓｉｎθ2／θ2（≦１）を掛けた値であると解釈することができる。 Therefore, the physical quantity obtained by obtaining the minimum wavelength λ 1 and the maximum wavelength λ 2 from the spectral reflection spectrum and giving the interference order m and the refractive index n 2 of the film is expressed by sin θ 2 / θ 2 (≦ 1) as the film thickness value. It can be interpreted as a multiplied value.

上記のような考え方に基づくと、対物レンズにより収束させた照明光を使用しても、取得した分光反射率データの極大波長、極小波長から、垂直入射時と同等な精度で膜厚値を求めることが可能となる。
すなわち、従来方法により求めた膜厚値に、ｓｉｎθ2／θ2（≦１）の逆数であるθ2／ｓｉｎθ2（≧１）を補正係数として掛けた値をもって、真の膜厚値とすることができる。なお、数式（１１）、数式（１２）から明らかなように、対物レンズ使用時の分光反射スペクトルから求まる極大波長、極小波長に、補正係数θ2／ｓｉｎθ2（≧１）を掛け、
補正済みの極大波長、極小波長を求めてから従来方法を適用することができるのはもちろんである。 Based on the above concept, even if illumination light converged by the objective lens is used, the film thickness value is obtained with the same accuracy as normal incidence from the maximum and minimum wavelengths of the acquired spectral reflectance data. It becomes possible.
That is, the true film thickness value is obtained by multiplying the film thickness value obtained by the conventional method by θ 2 / sin θ 2 (≧ 1), which is the inverse of sin θ 2 / θ 2 (≦ 1), as a correction coefficient. be able to. As is clear from Equations (11) and (12), the maximum and minimum wavelengths obtained from the spectral reflection spectrum when the objective lens is used are multiplied by a correction coefficient θ 2 / sin θ 2 (≧ 1),
It goes without saying that the conventional method can be applied after obtaining the corrected maximum and minimum wavelengths.

表１は、対物レンズを使用しないとき、つまり、厳密な垂直入射とみなせる条件のもとで取得した分光反射率データを用いて、従来方法により求めた膜厚値を記したものである。なお、被測定部分の近傍を触針式の段差計で測定したところ、膜厚の測定値は１６６９ｎｍであり、対物レンズを使用しない場合においては触針式の段差計による測定値と十分よく一致することを確認した。   Table 1 shows the film thickness values obtained by the conventional method using the spectral reflectance data obtained when the objective lens is not used, that is, under conditions that can be regarded as strict normal incidence. When the vicinity of the part to be measured was measured with a stylus type step meter, the measured value of the film thickness was 1669 nm, and when the objective lens was not used, it was in good agreement with the measured value with the stylus type step meter. Confirmed to do.

以下、対物レンズを使用したときの分光反射率データを用いて、従来方法により求めた膜厚値（以下「補正前膜厚値」と記す）、および、補正前膜厚値にθ2／ｓｉｎθ2（≧１）を掛けた値（以下「補正済み膜厚値」と記す）を示す。
表２は、倍率１０倍の対物レンズ（ＮＡ＝０．２５）、表３は倍率２０倍の対物レンズ（ＮＡ＝０．４０）、表４は、倍率５０倍の対物レンズ（ＮＡ＝０．５５）を使用したときの結果をまとめたものである。 Hereinafter, using the spectral reflectance data when the objective lens is used, the film thickness value obtained by the conventional method (hereinafter referred to as “film thickness value before correction”) and the film thickness value before correction are θ 2 / sin θ. 2 Indicates a value multiplied by (≧ 1) (hereinafter referred to as “corrected film thickness value”).
Table 2 shows a 10 × magnification objective lens (NA = 0.25), Table 3 shows a 20 × magnification objective lens (NA = 0.40), and Table 4 shows a 50 × magnification objective lens (NA = 0.0). 55 is a summary of the results obtained when using (55).

表２〜表４に記したように、倍率１０倍の対物レンズ（ＮＡ＝０．２５）、倍率２０倍の対物レンズ（ＮＡ＝０．４０）、倍率５０倍の対物レンズ（ＮＡ＝０．５５）を使用したときの補正前膜厚値はそれぞれ、１６６４ｎｍ、１６５４ｎｍ、１６２９ｎｍであったのに対し、補正済み膜厚値はそれぞれ、１６７０ｎｍ、１６７２ｎｍ、１６６３ｎｍとなり、いずれも触針式段差計による測定値１６６９ｎｍに十分よく一致する結果が得られた。 As described in Tables 2 to 4, an objective lens having a magnification of 10 times (NA = 0.25), an objective lens having a magnification of 20 times (NA = 0.40), and an objective lens having a magnification of 50 times (NA = 0.0). 55), the film thickness values before correction were 1664 nm, 1654 nm, and 1629 nm, respectively, whereas the corrected film thickness values were 1670 nm, 1672 nm, and 1663 nm, respectively. The result was in good agreement with the measured value of 1669 nm.

同一試料の特定位置に、開口数の異なる複数種類のレンズを介して照明光を照射したときの分光反射率データを示す説明図である。It is explanatory drawing which shows the spectral reflectance data when the illumination light is irradiated to the specific position of the same sample through several types of lenses with different numerical apertures. 垂直入射における膜表面からの反射光と、膜と基板との境界面からの反射光との光路差を示す説明図である。It is explanatory drawing which shows the optical path difference of the reflected light from the film | membrane surface in normal incidence, and the reflected light from the interface of a film | membrane and a board | substrate. 斜入射における膜表面からの反射光と、膜と基板との境界面からの反射光との光路差を示す説明図である。It is explanatory drawing which shows the optical path difference of the reflected light from the film | membrane surface in oblique incidence, and the reflected light from the interface of a film | membrane and a board | substrate. 対物レンズ使用時における照明光の入射角度を示す説明図である。It is explanatory drawing which shows the incident angle of the illumination light at the time of objective lens use.

符号の説明Explanation of symbols

Ｉ・・・照明光（入射光）
Ｒ1 ・・膜表面からの反射光
Ｒ2 ・・膜と基板との境界面からの反射光
Ｌ・・・対物レンズ
ａ・・・膜表面
ｂ・・・膜と基板との境界面（基板表面）
ｄ・・・膜厚
ｎ1 ・・空気の屈折率
ｎ2 ・・膜の屈折率
ｎ3 ・・基板の屈折率 I: Illumination light (incident light)
R 1 .. Reflected light from the film surface R 2 ... Reflected light from the interface between the film and the substrate L ... Objective lens a ... Film surface b ... Interface between the film and the substrate (substrate surface)
d: film thickness n 1 .. air refractive index n 2 .. film refractive index n 3 .. substrate refractive index

Claims (2)

基板上に形成された薄膜の膜表面の微小領域部分に、対物レンズにより収束した照明光をその光軸が膜表面に対して垂直になるように照射し、その微小領域部分から反射された光を分光して取得される分光反射率データの極大波長、極小波長から前記薄膜の膜厚値を求めるピークバレー法による膜厚測定方法において、前記ピークバレー法により算出した膜厚値は、対物レンズの開口数に応じた照明光の斜入射の影響を含む膜厚値であるという仮定のもとに、前記ピークバレー法により算出した膜厚値を補正して真の膜厚値とすることを特徴とする膜厚測定方法。   Illumination light focused by an objective lens is irradiated onto a minute area on the surface of a thin film formed on the substrate so that its optical axis is perpendicular to the film surface, and light reflected from the minute area. In the film thickness measurement method by the peak valley method for obtaining the film thickness value of the thin film from the maximum wavelength and the minimum wavelength of the spectral reflectance data acquired by spectrally dividing the film thickness value calculated by the peak valley method, the objective lens Under the assumption that the film thickness value includes the influence of oblique incidence of illumination light according to the numerical aperture of the film thickness, the film thickness value calculated by the peak valley method is corrected to obtain a true film thickness value. A characteristic film thickness measuring method. 前記補正が、ピークバレー法により算出した膜厚値に、θ2／ｓｉｎθ2（≧１）を補正係数として掛ける補正であることを特徴とする請求項１記載の膜厚測定方法。 2. The film thickness measurement method according to claim 1, wherein the correction is correction by multiplying a film thickness value calculated by a peak valley method by θ 2 / sin θ 2 (≧ 1) as a correction coefficient.
JP2005012479A 2005-01-20 2005-01-20 Method for measuring film thickness Pending JP2006201016A (en)

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