JPH0665963B2 - Fine groove depth measuring device - Google Patents
Fine groove depth measuring deviceInfo
- Publication number
- JPH0665963B2 JPH0665963B2 JP23288686A JP23288686A JPH0665963B2 JP H0665963 B2 JPH0665963 B2 JP H0665963B2 JP 23288686 A JP23288686 A JP 23288686A JP 23288686 A JP23288686 A JP 23288686A JP H0665963 B2 JPH0665963 B2 JP H0665963B2
- Authority
- JP
- Japan
- Prior art keywords
- light
- groove depth
- optical path
- path difference
- fine groove
- Prior art date
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Description
【発明の詳細な説明】 〈産業上の利用分野〉 本発明は超LSI製造プロセスの検査技術に関し、特には
微細溝深さ測定技術に関する。DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to an inspection technique for a VLSI manufacturing process, and more particularly to a fine groove depth measuring technique.
〈従来の技術〉 現在、メガビット級のダイナミックRAMを実現するため
に、従来の２次元的な素子形成の枠組みを越えて３次元
的な素子形成技術が開発されつつある。その一例とし
て、従来のシリコン表面に素子を形成する方法に代わっ
て、シリコン表面に微細な溝を形成し溝側面にも素子を
形成することにより、実行的な表面積を増加させ集積度
を向上させる方法がある。本方法において形成されるシ
リコン溝の典型的な寸法は、更に高集積化を図るための
溝幅数100nmと狭く、深さ数μｍであり、溝のアスペク
ト比は（溝深さと溝幅の比）５から10にも達する。本方
法を使用して超LSI製造するためには、この溝の深さを
正確に測定し、そのデータに基づいて工程管理を行う必
要がある。<Prior Art> Currently, in order to realize a megabit-class dynamic RAM, a three-dimensional element formation technology is being developed beyond the conventional two-dimensional element formation framework. As an example, instead of the conventional method of forming an element on the silicon surface, by forming a fine groove on the silicon surface and forming an element on the groove side surface, the effective surface area is increased and the degree of integration is improved. There is a way. The typical dimensions of the silicon trenches formed by this method are as narrow as a few 100 nm in width and a depth of several μm for higher integration, and the aspect ratio of the trench is (ratio of trench depth to trench width). ) It reaches 5 to 10. In order to manufacture a VLSI using this method, it is necessary to accurately measure the depth of this groove and perform process control based on that data.
溝の深さを測定装置として、従来から触針式表面荒さ測
定装置が用いられている。前記触針式測定装置の場合、
触針の先端の曲率半径が数μ程度であるため、上述の如
く寸法サブミクロンの溝には触針が入らず、深さの測定
が不可能であるという問題があった。また、たとえ触針
が溝に入ったとしても接触測定であるので基板を汚染し
やすいという欠点もあった。以上の問題を解決するため
に、微細溝深さ測定としては、一般に、基板を割り、断
面走査電子顕微鏡写真（以下SEM断面写真）を撮る方法
が行われている。A stylus type surface roughness measuring device has been conventionally used as a measuring device for the depth of a groove. In the case of the stylus type measuring device,
Since the radius of curvature of the tip of the stylus is about several μ, the stylus does not enter the submicron-sized groove as described above, and there is a problem that the depth cannot be measured. Further, even if the stylus enters the groove, it is a contact measurement, so that the substrate is easily contaminated. In order to solve the above problems, a method of dividing a substrate and taking a cross-sectional scanning electron microscope photograph (hereinafter referred to as SEM cross-sectional photograph) is generally performed as the measurement of the fine groove depth.
〈発明が解決しようとする問題点〉 上述するSEM断面写真を撮って溝深さを測定する方法
は、サンプルを破壊しなければならないため、超LSIの
製造工程の検査に常時用いることができない。従って、
製造工程での溝深さの管理は甘くならざるを得ず、この
ため、工程のマージンを多く見積る必要が発生し、ま
た、歩留にも悪影響を与えるという問題がある。<Problems to be Solved by the Invention> The above-described method of taking a SEM cross-sectional photograph to measure the groove depth cannot destroy the sample and cannot always be used for inspection of the VLSI manufacturing process. Therefore,
There is no choice but to manage the groove depth in the manufacturing process, and therefore, it is necessary to largely estimate the margin of the process and there is a problem that the yield is also adversely affected.
〈問題を解決するための手段〉 本発明は、上述する問題を解決するためになされたもの
で、一又は複数の微細溝を所持する面に光を照射するた
めの光源と、前記面に対して、垂直方向に、前記光源の
照射光及び前記面からの反射光を導く顕微鏡と、該顕微
鏡により導出された前記微細溝底面からの反射光と一又
は複数の微細溝を所持する面の表面からの反射光との干
渉光を多チャンネル型受光素子を用いて受光し、分光す
る分光器と、該分光器出力による分光スペクトル信号か
ら最大エントロピー法を用いて光学行路差情報を形成す
る演算手段と、前記光学行路差情報に基づいて微細溝深
さを算出する演算手段とを備えてなることを特徴とする
微細溝深さ測定装置を提供するものである。<Means for Solving Problems> The present invention has been made to solve the above-mentioned problems, and a light source for irradiating light on a surface having one or a plurality of fine grooves, and the surface. And a microscope for guiding the irradiation light of the light source and the reflected light from the surface in the vertical direction, and the reflected light from the bottom surface of the fine groove derived by the microscope and the surface of the surface having one or more fine grooves. A spectroscope for receiving the interference light with the reflected light from the multi-channel type light receiving element and splitting the light, and an arithmetic means for forming optical path difference information from the spectral spectrum signal by the output of the spectroscope using the maximum entropy method. And a calculation means for calculating the fine groove depth based on the optical path difference information, to provide a fine groove depth measuring device.
〈作 用〉 上述の如く溝深さの測定を、光を照射してその反射光か
ら得られる情報を利用して行なうことにより、被測定基
板に接触する必要がないため該基板を汚染することがな
く、また該基板を破壊する必要がないため、歩留りの向
上が図れるものである。<Operation> By measuring the groove depth as described above by utilizing light and utilizing information obtained from the reflected light, it is not necessary to contact the substrate to be measured, so that the substrate is contaminated. In addition, the yield is improved because there is no need to destroy the substrate.
〈実施例〉 第１図は本発明の一実施例であり、基板シリコンの溝掘
りエッチング後の検査に使用した場合の微細溝深さ測定
装置の構成図である。光源１から出た光は顕微鏡のレン
ズ系を通して基板２上に集光される。該基板２には微細
溝が加工されている。基板２からの反射光は上記レンズ
系とスリット３を通して回折格子４に導かれ分光され
る。分光強度の測定は多チャンネル型の受光素子５を用
いて機械的走査なしに一度に行う。多チャンネル型の受
光素子は、（１）分光時間が短い（演算を含め３秒以
内）、（２）情報の利用効率が高い（明るい）、という
長所を持っている。本実施例では400nmから800nmの領域
を約400チャンネルの直線型多チャンネル受光素子を用
いている。<Embodiment> FIG. 1 is an embodiment of the present invention and is a configuration diagram of a fine groove depth measuring apparatus when used for inspection after grooving etching of substrate silicon. The light emitted from the light source 1 is focused on the substrate 2 through the lens system of the microscope. The substrate 2 is processed with fine grooves. The reflected light from the substrate 2 is guided to the diffraction grating 4 through the lens system and the slit 3 and is dispersed. The spectral intensity is measured at once using the multi-channel type light receiving element 5 without mechanical scanning. The multi-channel type light receiving element has the advantages that (1) the spectral time is short (within 3 seconds including calculation), and (2) the information utilization efficiency is high (bright). In this embodiment, a linear multi-channel light receiving element having about 400 channels in the region of 400 nm to 800 nm is used.
受光素子５で得られた信号は、データ処理部６において
デジタル化された後、後述する波形処理技術を演算処理
される。The signal obtained by the light receiving element 5 is digitized by the data processing unit 6 and then arithmetically processed by a waveform processing technique described later.
第２図は、0.8μｍの幅の溝が1.6μｍの周期で繰り返さ
れるパターン（サンプルＳ−１）について、上記多チャ
ンネル受光素子５から得られる反射分光スペクトル強度
を示し、第３図は1.2μｍの幅の溝が2.4μｍの周期で繰
り返されるパターン（サンプルＳ−２）について、上記
多チャンネル型受光素子５から得られる反射分光スペク
トル強度を示している。第２図、第３図において横軸は
波数であり、分光面積は約20μｍ四方である。顕微鏡の
対物レンズは10倍を用いる。光学系の開口数を最適化す
ることにより、アスペクト比の大きい溝パターンでも深
い溝底部と表面からの反射光が干渉し、第２図や第３図
のような干渉スペクトルが得られることが見いだされ
た。FIG. 2 shows the reflection spectral spectrum intensity obtained from the multi-channel light receiving element 5 for a pattern (sample S-1) in which a groove having a width of 0.8 μm is repeated at a cycle of 1.6 μm, and FIG. 3 shows 1.2 μm. The reflection spectral spectrum intensity obtained from the multi-channel type light receiving element 5 is shown for the pattern (Sample S-2) in which the groove having the width of is repeated at a cycle of 2.4 μm. In FIGS. 2 and 3, the horizontal axis represents the wave number and the spectral area is about 20 μm square. The objective lens of the microscope uses 10 times. By optimizing the numerical aperture of the optical system, it has been found that even in a groove pattern with a large aspect ratio, the reflected light from the deep groove bottom and the surface interfere, and an interference spectrum as shown in FIGS. 2 and 3 is obtained. It was
ここでサンプルＳ−１はエッチング終了後マスク材料と
して用いたSiO2を除去したもので、サンプルＳ−２はエ
ッチング直後のものである。即ちサンプルＳ−１では１
種類の干渉が繰返して出現しているのに対し、サンプル
Ｓ−２の反射分光スペクトル強度である第３図におい
て、２種以上の周期を持つ信号が観測されている。これ
は、前記サンプルＳ−２が第４図に示す断面図をもち、
SiO2表面の反射光,SiO2とSi境界面からの反射光、
溝底部からの反射光とすると、SiO2の膜厚とSiのエッ
チング溝深さに対応して３つの光学行路差が存在するた
めに起こるものである。Here, the sample S-1 is a sample obtained by removing SiO 2 used as a mask material after completion of etching, and the sample S-2 is a sample immediately after etching. That is, 1 in sample S-1
While interference of various types repeatedly appears, signals having two or more types of periods are observed in FIG. 3, which is the reflection spectral spectrum intensity of sample S-2. This has the cross-sectional view of the sample S-2 shown in FIG.
Reflected light from the SiO 2 surface, reflected light from the SiO 2 and Si interface,
This is because the reflected light from the bottom of the groove has three optical path differences corresponding to the film thickness of SiO 2 and the etching groove depth of Si.
ところで、溝深さの検査はエッチング直後に行うのが望
ましい。これは、溝深さがスペックより浅い場合、追加
のエッチングを直ちに施すことが可能になるからであ
る。第３図の干渉スペクトルから、直ちに溝深さの情報
を得ることは困難である。そこで、スペクトル解析の手
法を用いて信号を分離しエッチング深さを得る方法を試
みた。本実施例では信号の解析方法として高速フーリエ
変換（以下FFT）を採用し、それらはデータ処理部６に
おいて実行する。By the way, it is desirable to inspect the groove depth immediately after etching. This is because if the groove depth is shallower than the spec, additional etching can be immediately performed. It is difficult to immediately obtain information on the groove depth from the interference spectrum of FIG. Therefore, we attempted to obtain the etching depth by separating the signals using the method of spectrum analysis. In this embodiment, a fast Fourier transform (hereinafter referred to as FFT) is adopted as a signal analysis method, and these are executed in the data processing unit 6.
FFTの数値演算は、パスカル言語を用いて記述し8086系
のCPU用にコンパイルしたオブジェクトプログラムを用
いて行った。本プログラムを用い、波数軸に対して256
点のデータを演算するのに要する時は、FFTでは約10秒
である。これは、製造工程での検査を実施するのに十分
なスピードである。Numerical calculation of FFT was performed by using an object program written in Pascal language and compiled for 8086 CPU. Using this program, 256 on the wavenumber axis
FFT takes about 10 seconds to calculate point data. This is fast enough to perform inspections in the manufacturing process.
第５図は、第２図及び第３図の反射分光スペクトル信号
にFFTを施した結果を示す。縦軸は反射分光スペクトル
強度を示し、横軸は光学行路差情報に相当する。また第
５図中にて観測されるピークにおいて、サンプルＳ−１
のピークをＡ、サンプルＳ−２の２つのピークをそれぞ
れB,Cと名付けると、ピークＡはSi基板表面の反射光と
溝底部からの反射光との干渉に基いて出現している出力
であり、横軸の値が両反射光の光学行路差を示し、ピー
クＢは第４図中の光ととの光学行路差を示し、ピー
クＣは第４図中の光ととの光学行路差を示す。この
光学行路差に基づき、Si溝深さ及びSiO2膜膜厚が得られ
る。FIG. 5 shows the results of FFT of the reflection spectrum signals of FIGS. 2 and 3. The vertical axis represents the reflection spectral spectrum intensity, and the horizontal axis corresponds to the optical path difference information. Also, in the peak observed in FIG. 5, sample S-1
When the peak of A is designated as A and the two peaks of sample S-2 are designated as B and C, respectively, peak A is an output that appears based on the interference between the reflected light from the Si substrate surface and the reflected light from the groove bottom. The value on the horizontal axis indicates the optical path difference between the two reflected lights, the peak B indicates the optical path difference with the light in FIG. 4, and the peak C indicates the optical path difference with the light in FIG. Indicates. Based on this optical path difference, the Si groove depth and the SiO 2 film thickness can be obtained.
表１はサンプルＳ−1,S−２について、FFT処理にて得ら
れた光学行路差、該光学行路差から算出した溝深さ若し
くはSiO2膜膜厚と、SEM断面写真から得た各測定結果と
を分解能と共に示す。ここでSiO2の屈折率は1.45とし
て、計算を行なった。Table 1 shows the optical path difference obtained by the FFT process, the groove depth or the SiO 2 film thickness calculated from the optical path difference, and the respective measurements obtained from the SEM cross-sectional photographs for the samples S-1 and S-2. The result and the resolution are shown. Here, the calculation was performed assuming that the refractive index of SiO 2 is 1.45.
ここで、フーリエ変換の分解能とは、離散フーリエ変換
の理論によって与えられる量で、変換前のシグナルの帯
域幅の逆数に相当する。従って、可視領域の分光を行う
限り、フーリエ変換の分解能は光学行路差にして800nm
前後で大きい。 Here, the resolution of the Fourier transform is an amount given by the theory of the discrete Fourier transform, and corresponds to the reciprocal of the bandwidth of the signal before the transform. Therefore, the resolution of the Fourier transform is 800 nm in terms of optical path difference as long as spectroscopy in the visible region is performed.
It is big before and after.
そこで分光スペクトル信号の演算処理の第２例として、
最大エントロピー法（以下MEM）を採用した。Therefore, as a second example of the calculation processing of the spectrum signal,
The maximum entropy method (MEM) was adopted.
MEMにおいても上記FFT同様パスカル言語を用いて記述し
8086系のCPU用にコンパイルしたオブジェクトプログラ
ムを用いて行った。本プログラムを用い、波数軸に対し
て256点のデータを演算するのに要する時間は、MEMでは
約70秒である。これも、製造工程での検査を実施するの
に十分なスピードである。In MEM as well, it is described using Pascal language as in the above FFT.
This was done using an object program compiled for 8086 CPUs. MEM takes about 70 seconds to calculate 256 points of data on the wavenumber axis using this program. Again, this is fast enough to perform inspections in the manufacturing process.
第６図は第２図及び第３図の反射分光スペクトル信号に
MEMを施した結果を示す。縦軸は反射分光スペクトル強
度を示し、横軸は光学行路差情報に相当する。また第６
図中にて観測されるピークにおいて、サンプルＳ−１の
ピークをA1,サンプルＳ−２の２つのピークをそれぞれB
1,C1と名付けると、ピークA1はSi基板表面の反射光と溝
底部からの反射光との干渉に基いて出現し、横軸の値は
両反射光の光学行路差を示し、ピークB1は第４図中の光
ととの光学行路差を示し、ピークC1は第４図中の光
ととの光学行路差を示す。この光学行路差に基づ
き、Si溝深さ及びSiO2膜膜厚が得られる。FIG. 6 shows the reflection spectrum signal of FIGS. 2 and 3.
The result of MEM is shown. The vertical axis represents the reflection spectral spectrum intensity, and the horizontal axis corresponds to the optical path difference information. Also the 6th
Of the peaks observed in the figure, the peak of sample S-1 is A 1 and the two peaks of sample S-2 are B respectively.
Named 1 , C 1 , the peak A 1 appears based on the interference between the reflected light from the Si substrate surface and the reflected light from the groove bottom, and the value on the horizontal axis indicates the optical path difference between the two reflected lights. B 1 shows the optical path difference with the light in FIG. 4, and the peak C 1 shows the optical path difference with the light in FIG. Based on this optical path difference, the Si groove depth and the SiO 2 film thickness can be obtained.
表２はMEM処理を実行することにて得られた光学行路
差、該光学行路差から算出した溝深さ及びSiO2膜膜厚
と、SEM断面写真から得た各測定結果とを分解能と共に
示す。ここでSiO2の屈折率は1.45として計算を行なっ
た。Table 2 shows the optical path difference obtained by executing the MEM process, the groove depth and the SiO 2 film thickness calculated from the optical path difference, and each measurement result obtained from the SEM cross-sectional photograph together with the resolution. . Here, the calculation was performed assuming that the refractive index of SiO 2 is 1.45.
MEMの場合は、計算点数を増やすことで計算上の分解能
はいくらでも小さくすることが可能であり、高精度で光
学行路差を求める目的にはMEMが適している。 In the case of MEM, the computational resolution can be reduced as much as possible by increasing the number of calculation points, and MEM is suitable for the purpose of obtaining the optical path difference with high accuracy.
表２中の、MEMより得た光学行路差をもとに算出した溝
深さ及びSiO2膜膜厚とSEM断面写真より得た溝深さ及びS
iO2膜膜厚とは、それぞれ測定の精度の範囲でよく一致
しており、MEMを用いた本実施例により微細溝深さ測定
が精度よく実現していることを示している。In Table 2, the groove depth and SiO 2 film thickness calculated based on the optical path difference obtained from MEM and the groove depth and S obtained from the SEM cross-sectional photograph
The iO 2 film thickness and the iO 2 film thickness are in good agreement with each other in the range of measurement accuracy, which shows that the measurement of the fine groove depth is accurately realized by this example using MEM.
処で、MEMでは予測誤差フィルターの次数の選択が重要
である。フィルター次数の選択法として次の３つの方法
を試した。By the way, in MEM, it is important to select the order of the prediction error filter. The following three methods were tried as a method of selecting the filter order.
（１） フィルター次数を１から順に増大させ最終予測
誤差の極小値を与えるフィルター次数を選択する。(1) The filter order is sequentially increased from 1 and the filter order that gives the minimum value of the final prediction error is selected.
（２） 設定されたフィルター次数の範囲の最終予測誤
差をすべて計算しその最小値を与えるフィルター次数を
選択する。(2) Calculate all final prediction errors within the set filter order range and select the filter order that gives the minimum value.
（３） フィルター次数を最終予測誤差の予測誤差フィ
ルター次数依存性に関わらず、あらかじめ設定された値
に固定して演算する。(3) The filter order is fixed to a preset value for calculation regardless of the dependence of the final prediction error on the prediction error filter order.
（１）の方法は演算時間は早いが、ノイズの多い波形を
観測するときに最終予測誤差のノイズによる振舞いを極
小値と見誤り、その結果、正しいスペクトル解析が不能
になる場合がある。（２）の方法は今回の信号解析で
は、多くの場合よい結果が得られた。ただし、微細溝の
面積が小さく溝底部から信号がマスク表面からの信号に
比べて小さい場合に、溝深さに相当する光学行路差をノ
イズと判断し消し去る場合がある。（３）は（２）で解
析できない場合に有効であり、大きな振幅に乗った小さ
い信号からもスペクトル解析が可能である。ただし、ま
れにノイズを信号と見誤り偽の光学行路差を与えること
がある。これを避けるため予想誤差フィルターの次数の
範囲を30から60にし、この範囲からフィルター次数を選
択するとよい。各種の構造の微細溝の測定結果から、
（２）と（３）を上記の特徴を意識しながら場合により
使い分けることが適当であることが分かった。実用的に
は、シリコン基板上に分光しやすい検査マークを作れば
（幅１μｍ前後の溝が２μｍ程度のピッチで並んでいる
パターン等）、（２）の方式で失敗なく溝深さの測定が
可能であることが確かめられた。なお、（３）において
偽の信号を見分けるためには、FFTの結果との信号の積
を取ることが有効である。The method (1) has a short calculation time, but when observing a noisy waveform, the behavior of the final prediction error due to noise may be mistaken as a minimum value, and as a result, correct spectrum analysis may be impossible. In the signal analysis of this time, the method of (2) obtained good results in many cases. However, when the area of the fine groove is small and the signal from the groove bottom is smaller than the signal from the mask surface, the optical path difference corresponding to the groove depth may be determined as noise and erased. (3) is effective when analysis cannot be performed in (2), and spectrum analysis is possible even from a small signal with a large amplitude. However, on rare occasions, noise may be mistaken for a signal to give a false optical path difference. To avoid this, set the order of the prediction error filter to 30 to 60 and select the filter order from this range. From the measurement results of fine grooves of various structures,
It has been found that it is appropriate to use (2) and (3) properly depending on the situation while being aware of the above characteristics. Practically, if an inspection mark that is easy to disperse is made on a silicon substrate (such as a pattern in which grooves having a width of about 1 μm are arranged at a pitch of about 2 μm), it is possible to measure the groove depth without failure by the method (2). It was confirmed to be possible. In order to discriminate the false signal in (3), it is effective to take the product of the signal and the FFT result.
本実施例では、シリコン基板の溝掘りエッチング後の溝
深さ測定の場合を述べたが、一般の微細溝の深さ測定に
本発明が利用できるのは明白である。In this embodiment, the case of measuring the groove depth after the trench etching of the silicon substrate has been described, but it is obvious that the present invention can be used for measuring the depth of general fine grooves.
また、一般の多層膜や基板上に形成された微細溝の底面
に形成された各種膜の光学膜厚測定に関しても本発明が
有効であると考えられる。Further, the present invention is considered to be effective for the measurement of the optical film thickness of general multi-layer films and various films formed on the bottom surface of the fine grooves formed on the substrate.
〈効 果〉 本発明を用いて、微細溝底面からの反射光と該微細溝所
持面の表面からの反射光との干渉光によるスペクトル情
報から最大エントロピー法を用いて微細溝深さを測定す
ることによって、測定対象の複数の微細溝が規則的に配
列されているか否かにかかわらず、従来困難であった値
の小さなスペクトル情報からの微細溝深さのモニターを
工程途中で正確にできるようになった。その結果、微細
溝を用いるLSIの製造プロセスの信頼性が向上し、高集
積メモリーに代表される超LSIの歩留りが向上する。<Effect> Using the present invention, the depth of the fine groove is measured using the maximum entropy method from the spectral information by the interference light between the reflected light from the bottom surface of the fine groove and the reflected light from the surface of the holding surface of the fine groove. Therefore, regardless of whether or not a plurality of fine grooves to be measured are regularly arranged, it is possible to accurately monitor the fine groove depth from the spectral information of a small value, which was difficult in the past, during the process. Became. As a result, the reliability of the manufacturing process of the LSI using the fine groove is improved, and the yield of the VLSI represented by the highly integrated memory is improved.
第１図は本発明の一実施例による構成図、第２図はサン
プルＳ−１の反射分光スペクトル強度を波数に対しプロ
ットした図、第３図はサンプルＳ−２の反射分光スペク
トル強度を波数に対しプロットした図、第４図はサンプ
ルＳ−２の断面図、第５図は第２図及び第３図の反射分
光スペクトル信号を高速フーリエ変換した結果を表す
図、第６図は第２図及び第３図の反射分光スペクトル信
号を最大エントロピー法にて処理した結果を表す図であ
る。 1:光源、2:基板、3:スリット、4:回折格子、5:多チャン
ネル受光素子、6:データ処理部FIG. 1 is a configuration diagram according to one embodiment of the present invention, FIG. 2 is a diagram in which the reflection spectral spectrum intensity of sample S-1 is plotted against the wave number, and FIG. 3 is the reflection spectral spectrum intensity of sample S-2. FIG. 4 is a sectional view of the sample S-2, FIG. 5 is a view showing the result of the fast Fourier transform of the reflection spectrum signal of FIGS. 2 and 3, and FIG. It is a figure showing the result of having processed the reflection spectrum signal of FIG. 3 and FIG. 3 by the maximum entropy method. 1: Light source, 2: Substrate, 3: Slit, 4: Diffraction grating, 5: Multi-channel light receiving element, 6: Data processing unit
Claims (1)
射するための光源と、 前記面に対して、垂直方向に、前記光源の照射光及び前
記面からの反射光を導く顕微鏡と、 該顕微鏡により導出された前記微細溝底面からの反射光
と一又は複数の微細溝を所持する面の表面からの反射光
との干渉光を多チャンネル型受光素子を用いて受光し、
分光する分光器と、 該分光器出力による分光スペクトル信号から最大エント
ロピー法を用いて光学行路差情報を形成する演算手段
と、 前記光学行路差情報に基づいて微細溝深さを算出する演
算手段とを備えてなることを特徴とする微細溝深さ測定
装置。1. A light source for irradiating a surface having one or a plurality of fine grooves with light, and a microscope for guiding the irradiation light of the light source and the reflected light from the surface in a direction perpendicular to the surface. And receiving the interference light of the reflected light from the bottom surface of the fine groove and the reflected light from the surface of the surface holding the one or more fine grooves, which is derived by the microscope, using a multi-channel light receiving element,
A spectroscope for spectroscopic analysis, an arithmetic means for forming optical path difference information from the spectral spectrum signal from the spectroscope output by using the maximum entropy method, and an operation means for calculating a fine groove depth based on the optical path difference information. A fine groove depth measuring device comprising:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23288686A JPH0665963B2 (en) | 1986-09-29 | 1986-09-29 | Fine groove depth measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23288686A JPH0665963B2 (en) | 1986-09-29 | 1986-09-29 | Fine groove depth measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6385305A JPS6385305A (en) | 1988-04-15 |
| JPH0665963B2 true JPH0665963B2 (en) | 1994-08-24 |
Family
ID=16946379
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23288686A Expired - Lifetime JPH0665963B2 (en) | 1986-09-29 | 1986-09-29 | Fine groove depth measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0665963B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102012102826B4 (en) * | 2011-04-06 | 2020-03-26 | Precitec Optronik Gmbh | Apparatus and method for determining a depth of a region which has a high aspect ratio and projects into a surface of a semiconductor wafer |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5087121A (en) * | 1987-12-01 | 1992-02-11 | Canon Kabushiki Kaisha | Depth/height measuring device |
| JPH0797018B2 (en) * | 1992-05-13 | 1995-10-18 | インターナショナル・ビジネス・マシーンズ・コーポレイション | Depth measuring method and device |
| JP5186129B2 (en) | 2006-08-25 | 2013-04-17 | 大日本スクリーン製造株式会社 | Method and apparatus for measuring groove pattern depth |
| JP2011196785A (en) * | 2010-03-18 | 2011-10-06 | Disco Corp | Measurement apparatus and laser processing machine of to-be-processed object held on chuck table |
| JP5888111B2 (en) * | 2012-05-18 | 2016-03-16 | 株式会社島津製作所 | Etching monitor device |
| JP2014002068A (en) * | 2012-06-19 | 2014-01-09 | Shimadzu Corp | Thickness monitoring device, etching depth monitoring device, and thickness monitoring method |
-
1986
- 1986-09-29 JP JP23288686A patent/JPH0665963B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102012102826B4 (en) * | 2011-04-06 | 2020-03-26 | Precitec Optronik Gmbh | Apparatus and method for determining a depth of a region which has a high aspect ratio and projects into a surface of a semiconductor wafer |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6385305A (en) | 1988-04-15 |
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