JP2728773B2 - Apparatus and method for evaluating thickness of semiconductor multilayer thin film - Google Patents
Apparatus and method for evaluating thickness of semiconductor multilayer thin filmInfo
- Publication number
- JP2728773B2 JP2728773B2 JP24143990A JP24143990A JP2728773B2 JP 2728773 B2 JP2728773 B2 JP 2728773B2 JP 24143990 A JP24143990 A JP 24143990A JP 24143990 A JP24143990 A JP 24143990A JP 2728773 B2 JP2728773 B2 JP 2728773B2
- Authority
- JP
- Japan
- Prior art keywords
- fourier transform
- thin film
- multilayer thin
- thickness
- semiconductor multilayer
- 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 - Lifetime
Links
Landscapes
- Length Measuring Devices By Optical Means (AREA)
Description
【発明の詳細な説明】 ［産業上の利用分野］ この発明は、半導体多層薄膜の膜厚を評価する装置及
び方法、特に、半導体結晶のエピタキシャル成長による
多層薄膜構造の各層の膜厚を、非破壊・非接触で測定す
る評価装置及び評価方法に関するものである。Description: BACKGROUND OF THE INVENTION The present invention relates to an apparatus and a method for evaluating the thickness of a semiconductor multilayer thin film, and more particularly, to non-destructive measurement of the thickness of each layer of a multilayer thin film structure by epitaxial growth of a semiconductor crystal. -It relates to an evaluation device and an evaluation method for non-contact measurement.
［従来の技術］ 従来のフーリエ変換赤外分光法（FTIR法）による膜厚
測定法について、第３図を用いてその概念を簡単に説明
する。第３図は従来のFTIR法による膜厚評価装置の光学
系の概念図であり、第４図はその全体構成図である。こ
れらの図において、光源（１）を射出し非球面鏡（２）
で平行にされた光束は、マイケルソン干渉計（３）に導
入される。マイケルソン干渉計（３）内では、入射して
きた光束はビーム・スプリッター（４）で二光束に分割
され、固定鏡（５）と移動鏡（６）とで各々反射された
あと合成され干渉する。この時間的に変調された波数の
異なる干渉光束がミラー（７）により試料（８）に照射
され、検知器（９）で検出される。以上の光源（１）〜
検出器（９）によって膜厚評価装置の光学系（10）が構
成される。[Prior Art] The concept of a conventional film thickness measurement method using Fourier transform infrared spectroscopy (FTIR method) will be briefly described with reference to FIG. FIG. 3 is a conceptual diagram of an optical system of a conventional film thickness evaluation apparatus using the FTIR method, and FIG. 4 is an overall configuration diagram thereof. In these figures, a light source (1) is emitted and an aspherical mirror (2) is emitted.
The collimated light beam is introduced into the Michelson interferometer (3). In the Michelson interferometer (3), the incident light beam is split into two light beams by a beam splitter (4), and the two light beams are reflected by a fixed mirror (5) and a movable mirror (6), and then combined and interfere. . The temporally modulated interference light beams having different wave numbers are irradiated on the sample (8) by the mirror (7) and detected by the detector (9). Light source (1) above
The optical system (10) of the film thickness evaluation device is constituted by the detector (9).
検出器（９）によって測定されたインターフェログラ
ム（すなわち空間干渉強度波形であってノイズを含むも
の）は、フーリエ変換手段（11）によりフーリエ変換さ
れ反射スペクトルを得る。この反射スペクトルから、測
光感度のない波数領域を取り除くフィルタリング処理を
フィルタリング手段（12）により行った後、逆フーリエ
変換を行うことによってノイズが除去された空間干渉強
度波形（Spatialgram）を得る。従来、逆フーリエ変換
はコサイン（cosine）逆フーリエ変換手段（13）により
行われていた。このようにして得られた空間干渉強度波
形の一例を第５図に示す。図に示す空間干渉強度波形に
おける各バースト・ピーク間の距離から、試料を構成す
る各層の膜厚を測定することができる。The interferogram measured by the detector (9) (that is, a spatial interference intensity waveform including noise) is Fourier-transformed by the Fourier transform means (11) to obtain a reflection spectrum. After performing a filtering process for removing a wave number region having no photometric sensitivity from the reflection spectrum by the filtering means (12), a spatial interference intensity waveform (Spatialgram) from which noise is removed is obtained by performing an inverse Fourier transform. Conventionally, the inverse Fourier transform has been performed by cosine inverse Fourier transform means (13). An example of the spatial interference intensity waveform obtained in this way is shown in FIG. The thickness of each layer constituting the sample can be measured from the distance between each burst peak in the spatial interference intensity waveform shown in the figure.
特に、半導体エピタキシャル層のような多層薄膜の膜
厚を精度よく測定するためには、特願平１−248850号に
示したように、測定試料の反射測光の平行光束系とし、
データ・サンプリング間隔の短縮を行うことが必要であ
る。In particular, in order to accurately measure the thickness of a multilayer thin film such as a semiconductor epitaxial layer, as shown in Japanese Patent Application No. 1-248850, a parallel beam system of reflection photometry of a measurement sample is used.
It is necessary to shorten the data sampling interval.
従来の半導体多層薄膜の膜厚評価装置は上述したよう
に構成され、その評価方法を第６図を用いてさらに詳細
に説明する。第６図は半導体薄膜（14）、（15）、（1
6）が半導体基板（17）上に形成された試料（６）を概
略的に示しており、試料（６）に入射した光束のうち各
層での一次元反射光のみの反射光路を模式的に示してい
る。半導体薄膜（14）、（15）、（16）の各層の膜厚及
び屈折率は各々（dl,n1）、（d2,n2）、（d3,n3）であ
り、半導体基板（17）の屈折率はnsとした。各層での反
射光は各々の光路長による位相差を生じ、試料（６）表
面で合成され干渉する。試料（６）表面での反射光成分
に対する第ｉ層−第ｉ＋１層界面での反射光成分の光路
差δｉは、次に示す（１）式で与えられる。The conventional semiconductor multilayer thin film thickness evaluation apparatus is configured as described above, and the evaluation method will be described in more detail with reference to FIG. FIG. 6 shows semiconductor thin films (14), (15), (1)
6) schematically shows the sample (6) formed on the semiconductor substrate (17), and the reflected light path of only one-dimensional reflected light from each layer in the light beam incident on the sample (6) is schematically shown. Is shown. The thickness and refractive index of each layer of the semiconductor thin films (14), (15), and (16) are (dl, n1), (d2, n2), and (d3, n3), respectively. The rate was ns. The reflected light from each layer causes a phase difference due to the optical path length, and is synthesized and interferes on the surface of the sample (6). The optical path difference δi of the reflected light component at the interface between the i-th layer and the (i + 1) -th layer with respect to the reflected light component on the surface of the sample (6) is given by the following equation (1).
空間干渉強度波形上にはこのδｉに対応する位置にバ
ースト・ピークが現れ、このピーク間の距離を測定して
（１）式より各膜厚diを得る。 A burst peak appears at a position corresponding to this δi on the spatial interference intensity waveform, and the distance between the peaks is measured to obtain each film thickness di from equation (1).
ここで、従来技術では反射スペクトルの空間干渉強度
波形への変換には次の（２）式に示すコサイン（cosin
e）項によるコサイン逆フーリエ変換を行っていた。Here, in the prior art, a cosine (cosin) shown in the following equation (2) is used to convert the reflection spectrum into a spatial interference intensity waveform.
e) The cosine inverse Fourier transform by the term was performed.
Ｒ（σ）：反射光強度 ｆ（σ）：フィルタリング関数 σ：波数（1/cm） X:距離（cm） σs/σe:測光波数端 第５図にこの空間干渉強度波形の一例を示す。各層の
界面に対応した位置にバースト・ピークが見られる。こ
のように、各層薄膜の反射スペクトルの逆フーリエ変換
処理による空間干渉強度波形の波形分析から、多層薄膜
の各膜厚を測定することができる。 R (σ): reflected light intensity f (σ): filtering function σ: wave number (1 / cm) X: distance (cm) s / σe: photometric wave end FIG. 5 shows an example of this spatial interference intensity waveform. A burst peak is found at a position corresponding to the interface of each layer. As described above, each film thickness of the multilayer thin film can be measured from the waveform analysis of the spatial interference intensity waveform by the inverse Fourier transform processing of the reflection spectrum of each thin film.
［発明が解決しようとする課題］ 上述したような半導体多層薄膜の膜厚評価装置及び方
法では、反射スペクトルをコサイン項のみのコサイン逆
フーリエ変換により行っていたので、空間干渉強度波形
上に現れるバースト波形は、フィルタリング条件（フィ
ルタリング関数ｆ（σ）の形やフィルタリング波数領域
等）により、バースト・ピークが上向き／下向きの逆位
相を取り得る。従って、被測定膜の膜厚が薄くなると、
例えば第７図に示す空間干渉強度波形に見られるよう
に、上向き、下向きピークを持つバースト波形が重なり
合うと、各ピークが合成波形の中に呑み込まれる形にな
り、ピーク位置を判読することが困難になる。[Problems to be Solved by the Invention] In the apparatus and method for evaluating the thickness of a semiconductor multilayer thin film as described above, since the reflection spectrum is performed by the cosine inverse Fourier transform of only the cosine term, the burst appearing on the spatial interference intensity waveform. Depending on the filtering condition (the shape of the filtering function f (σ), the filtering wavenumber region, etc.), the burst peak can take up / down opposite phases. Therefore, when the thickness of the film to be measured becomes thin,
For example, as shown in the spatial interference intensity waveform shown in FIG. 7, when burst waveforms having upward and downward peaks overlap, each peak becomes swallowed in the composite waveform, making it difficult to determine the peak position. become.
FTIR法による膜厚の測定方法において、薄膜測定限界
を限定する要因の主要なものとしては、測光波数範囲
（σｓ〜σｅ）がある。その内主に測光光学系かり決ま
る測光波数範囲の枠組みの中では、空間干渉強度波形上
でのバースト波形からのピーク位置の判読が重要とな
る。しかし、上述のように従来技術では、バースト波形
そのものに上向き／下向き位相の不安定要因があり、こ
れも薄膜の膜厚測定に限界をもたらす要因であった。In the method of measuring the film thickness by the FTIR method, the main factor that limits the measurement limit of the thin film is a photometric wavenumber range (σs to σe). In the framework of the photometric wave number range mainly determined by the photometric optical system, it is important to read the peak position from the burst waveform on the spatial interference intensity waveform. However, as described above, in the related art, the burst waveform itself has an upward / downward phase instability factor, which is also a factor that limits the measurement of the thin film thickness.
特願平１−248850号に示した平行光束反射測光とデー
タ・サンプリング間隔の短縮化を用いても、従来のコサ
イン逆フーリエ変換法では、化合物半導体エピタキシャ
ル層の膜厚測定は、約0.2μｍが限界であるという問題
点があった。Even with the parallel beam reflection photometry and the shortening of the data sampling interval shown in Japanese Patent Application No. 1-248850, the conventional cosine inverse Fourier transform method requires about 0.2 μm for measuring the thickness of the compound semiconductor epitaxial layer. There was a problem that it was the limit.
この発明は、このような問題点を解決するためになさ
れたもので、定められた測光波数範囲において、より薄
い多層薄膜の各層の膜厚を、より正確かつ安定に測定で
きる、FTIR法を応用した半導体多層薄膜の膜厚評価装置
及び膜厚評価方法を得ることを目的とする。The present invention has been made in order to solve such a problem, and uses the FTIR method, which can more accurately and stably measure the thickness of each layer of a thin multilayer thin film in a predetermined photometric wavenumber range. It is an object of the present invention to obtain a semiconductor multilayer thin film thickness evaluation apparatus and method.
［課題を解決するための手段］ この発明に係る半導体多層薄膜の膜厚評価装置及び膜
厚評価方法は、従来のコサイン逆フーリエ変換手段の代
わりに、複素パワー逆フーリエ変換手段を用いて空間干
渉強度波形を得るものである。[Means for Solving the Problems] A thickness evaluation apparatus and a thickness evaluation method for a semiconductor multilayer thin film according to the present invention provide spatial interference using complex power inverse Fourier transform instead of conventional cosine inverse Fourier transform. This is to obtain an intensity waveform.
［作 用］ この発明においては、複素変換により反射スペクトル
の限られた波数範囲内に現れる干渉波形中の偶及び奇関
数成分の両方が正しく変換され、また、パワー変換によ
り空間干渉強度波形上のバースト波形も全て同位相とな
るため、コサイン逆フーリエ変換手段を用いる場合に比
べ同じ測光波数範囲でも多くの情報が取り込まれ、バー
スト波形位相の不安定要因が無くなるので、バースト波
形の分離精度が向上し、薄膜測定限界が向上する。[Operation] In the present invention, both the even and odd function components in the interference waveform appearing within a limited wave number range of the reflection spectrum are correctly converted by the complex conversion, and the power conversion is performed on the spatial interference intensity waveform. Since all burst waveforms have the same phase, more information is captured even in the same photometric wavenumber range than when using the cosine inverse Fourier transform means, eliminating the instability factor of the burst waveform phase, improving the accuracy of burst waveform separation. Thus, the thin film measurement limit is improved.
［実施例］ 第１図はこの発明の一実施例による薄膜評価装置の全
体構成図であり、（10）〜（12）は上述した従来の薄膜
評価装置におけるものと全く同一である。また、光学系
（10）は第３図に示した従来のものと全く同一であり、
同様な操作により半導体多層薄膜の膜厚測定が行われ
る。Embodiment FIG. 1 is an overall configuration diagram of a thin film evaluation apparatus according to an embodiment of the present invention, and (10) to (12) are exactly the same as those in the above-described conventional thin film evaluation apparatus. The optical system (10) is exactly the same as the conventional one shown in FIG.
The thickness of the semiconductor multilayer thin film is measured by the same operation.
この発明では、フィルタリング処理が行われた反射ス
ペクトルを、複素パワー逆フーリエ変換手段（13A）を
用いることによって、空間干渉強度波形を得るものであ
る。フーリエ分光法において複素変換は一般的な基礎技
術であるが、半導体多層薄膜の膜厚測定を目的として、
反射スペクトルを空間干渉強度波形に逆フーリエ変換す
る場合には、複素パワー変換を応用した例は今まで全く
なかった。In the present invention, a spatial interference intensity waveform is obtained by using the complex power inverse Fourier transform means (13A) on the reflection spectrum that has been subjected to the filtering processing. In Fourier spectroscopy, complex transformation is a general basic technique, but for the purpose of measuring the thickness of a semiconductor multilayer thin film,
In the case where the reflection spectrum is subjected to the inverse Fourier transform into the spatial interference intensity waveform, there has been no example of applying the complex power conversion.
この発明による複素パワー逆フーリエ変換手段（13
A）では、反射スペクトルを逆フーリエ変換して空間干
渉強度波形を得る場合に、次の（３）式に示すようなコ
サイン（cosine）項及びサイン（sine）項を含むｅ（j2
πσｘ）による複素パワー変換により行うものである。The complex power inverse Fourier transform means (13
In A), when a spatial interference intensity waveform is obtained by performing an inverse Fourier transform on the reflection spectrum, e (j2) including a cosine term and a sine term as shown in the following equation (3).
(.pi..sigma.x).
次に、半導体多層薄膜が半導体基板上に形成された試
料の膜厚を測定し、その評価を行った。試料は、第６図
における半導体基板（17）としてGaAs基板上に、半導体
薄膜（14）、（15）、（16）としてそれぞれAlxGa1-xAs
（ｘ＝0.5、厚さ0.35μｍ）、AlxGa1-xAs（ｘ＝0.1、厚
さ0.1μｍ）、AlxGa1-xAs（ｘ＝0.5、厚さ1.4μｍ）を
形成した試料を用い、この発明による複素パワー逆フー
リエ変換手段（13A）を用いて得た空間干渉強度波形を
第２図に、従来のコサイン逆フーリエ変換手段（13）を
用いて得た空間干渉強度波形を第７図にそれぞれ示し
た。第７図に示したコサイン逆フーリエ変換では、２つ
のバースト波形が重なり合い非対称な波形になっている
ため、ピーク位置を判読することは困難であった。ま
た、この非対称な波形は、逆フーリエ変換時のフィルタ
リング条件に敏感であり微妙に形を変えるため、実際に
はこの波形からピークを見つて出し膜厚を得ることは不
可能である。一方、第２図に示したこの発明による空間
干渉強度波形では、ピーク位置間隔が約0.1μｍに相当
するものであるにもかかわらず、バースト波形は明確に
分離されており、実際の膜厚測定に用いるに足る安定し
た空間干渉強度波形である。 Next, the thickness of the sample in which the semiconductor multilayer thin film was formed on the semiconductor substrate was measured and evaluated. The sample was formed on a GaAs substrate as the semiconductor substrate (17) in FIG. 6, and Al x Ga 1 -x As as semiconductor thin films (14), (15) and (16), respectively.
(X = 0.5, thickness 0.35 μm), sample formed with Al x Ga 1-x As (x = 0.1, thickness 0.1 μm), Al x Ga 1-x As (x = 0.5, thickness 1.4 μm) FIG. 2 shows a spatial interference intensity waveform obtained using the complex power inverse Fourier transform means (13A) according to the present invention, and a spatial interference intensity waveform obtained using the conventional cosine inverse Fourier transform means (13). Each is shown in FIG. In the cosine inverse Fourier transform shown in FIG. 7, it is difficult to determine the peak position because the two burst waveforms overlap and become an asymmetric waveform. In addition, since this asymmetric waveform is sensitive to filtering conditions at the time of inverse Fourier transform and changes its shape slightly, it is actually impossible to find a peak from this waveform and obtain a film thickness. On the other hand, in the spatial interference intensity waveform according to the present invention shown in FIG. 2, although the peak position interval corresponds to about 0.1 μm, the burst waveform is clearly separated, and the actual film thickness measurement is performed. This is a stable spatial interference intensity waveform that is sufficient for use in the present invention.
本来、逆フーリエ変換における積分範囲が−∞から＋
∞である場合は、サイン項は原理的にゼロである筈であ
る。しかし、実際には測光光学条件や測定試料の光吸収
等により、極めて限られた波数範囲しか測定されないた
め、積分範囲も有限なものになる。そのため、本来のフ
ーリエ変換が充分に行えないため、変換された結果は本
来得られるべきものと異なってきて、それがサイン項を
ゼロではなくすることになる。そこで、フィルタリング
関数ｆ（σ）の形を適正化すると、有限域での積分でも
正しいフーリエ変換が得られ、サイン項も本来のゼロに
近づく。つまり、サイン項の大きさをモニタすることに
より、フィルタリングの状態が定量的に把握することが
でき、逆フーリエ変換により得られた空間干渉強度波形
の信頼性も向上する。これは、従来のコサイン項だけの
変換では全く判明しなかったことであり、測定精度の飛
躍的向上が可能となったものである。Originally, the integration range in the inverse Fourier transform was from -∞ to +
If ∞, the sine term should in principle be zero. However, in practice, only a very limited wavenumber range is measured due to photometric optical conditions, light absorption of the measurement sample, and the like, and the integration range is finite. As a result, the original Fourier transform cannot be performed sufficiently, and the transformed result is different from what should be originally obtained, which makes the sine term non-zero. Therefore, if the form of the filtering function f (σ) is optimized, a correct Fourier transform can be obtained even in integration in a finite range, and the sine term approaches the original zero. That is, by monitoring the magnitude of the sine term, the state of filtering can be grasped quantitatively, and the reliability of the spatial interference intensity waveform obtained by the inverse Fourier transform is improved. This has not been found at all by the conventional conversion of only the cosine term, and the measurement accuracy has been dramatically improved.
このように、複素パワー逆フーリエ変換による空間干
渉強度波形には、従来のコサイン逆フーリエ変換による
ものに比べより多くの情報が取り込まれ、かつ、各バー
スト波形が全て同位相となるため薄膜測定精度が向上
し、例えば従来法では0.2μｍが限界だった測光条件で
約0.1μｍの厚さの薄膜まで膜厚測定が可能となった。As described above, the spatial interference intensity waveform obtained by the complex power inverse Fourier transform captures more information than that obtained by the conventional cosine inverse Fourier transform, and all the burst waveforms have the same phase. For example, it has become possible to measure the thickness of a thin film having a thickness of about 0.1 μm under photometric conditions, which was limited to 0.2 μm in the conventional method.
［発明の効果］ この発明は、以上説明したとおり、従来のコサイン逆
フーリエ変換手段の代わりに、複素パワー逆フーリエ変
換手段を用いて空間干渉強度波形を得るので、定められ
た測光波数範囲において、より薄い多層薄膜の各層の膜
厚を、より正確かつ安定に測定できるという効果を奏す
る。[Effects of the Invention] As described above, the present invention obtains a spatial interference intensity waveform by using a complex power inverse Fourier transform unit instead of the conventional cosine inverse Fourier transform unit. There is an effect that the thickness of each layer of the thinner multilayer thin film can be measured more accurately and stably.
第１図はこの発明の一実施例による薄膜評価装置の全体
構成図、第２図はこの発明の一実施例により複素パワー
逆フーリエ変換を行った空間干渉強度波形を示す線図、
第３図はFTIR法による膜厚測定に用いる光学系を示す概
念図、第４図は従来の薄膜評価装置の全体構成図、第５
図及び第７図は従来のコサイン逆フーリエ変換により得
た空間干渉強度波形を示す線図、第６図は半導体多層薄
膜に照射された光束の多層薄膜内での光路を示す模式図
である。 図において、（１）は光源、（２）は非球面鏡、（３）
はマイケルソン干渉計、（４）はビーム・スプリッタ
ー、（５）は固定鏡、（６）は移動鏡、（７）はミラ
ー、（８）は試料、（９）は検知器、（10）は光学系、
（11）はフーリエ変換手段、（12）はフィルタリング手
段、（13A）は複素パワー逆フーリエ変換手段、（1
4）、（15）、（16）は半導体薄膜、（17）は半導体基
板である。 なお、各図中、同一符号は同一または相当部分を示す。FIG. 1 is an overall configuration diagram of a thin film evaluation apparatus according to an embodiment of the present invention, FIG. 2 is a diagram showing a spatial interference intensity waveform obtained by performing a complex power inverse Fourier transform according to an embodiment of the present invention,
FIG. 3 is a conceptual diagram showing an optical system used for film thickness measurement by the FTIR method, FIG.
7 and 8 are diagrams showing spatial interference intensity waveforms obtained by conventional cosine inverse Fourier transform, and FIG. 6 is a schematic diagram showing an optical path of a light beam irradiated on a semiconductor multilayer thin film in the multilayer thin film. In the figure, (1) is a light source, (2) is an aspherical mirror, (3)
Is a Michelson interferometer, (4) is a beam splitter, (5) is a fixed mirror, (6) is a moving mirror, (7) is a mirror, (8) is a sample, (9) is a detector, and (10) Is the optical system,
(11) is Fourier transform means, (12) is filtering means, (13A) is complex power inverse Fourier transform means, (1
4), (15) and (16) are semiconductor thin films, and (17) is a semiconductor substrate. In the drawings, the same reference numerals indicate the same or corresponding parts.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 服部 亮 兵庫県伊丹市瑞原４丁目１番地 三菱電 機株式会社北伊丹製作所内 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ryo Hattori 4-1-1 Mizuhara, Itami-shi, Hyogo Mitsubishi Electric Corporation Kita-Itami Works
Claims (2)
束を連続的に照射し上記試料によって反射した干渉光束
を検出してインターフェログラムを得る光学系と、 上記インターフェログラムをフーリエ変換して反射スペ
クトルを得るフーリエ変換手段と、 この反射スペクトルをフィルタリング処理するフィルタ
リング手段と、 フィルタリング処理した反射スペクトルを逆フーリエ変
換して空間干渉強度波形を得る複素パワー逆フーリエ変
換手段とを備えたことを特徴とする半導体多層薄膜の膜
厚評価装置。1. An optical system for continuously irradiating a semiconductor multilayer thin film sample with interference light beams having different wave numbers and detecting an interference light beam reflected by the sample to obtain an interferogram, and performing an Fourier transform on the interferogram. Fourier transform means for obtaining a reflection spectrum, filtering means for filtering the reflection spectrum, and complex power inverse Fourier transform means for performing an inverse Fourier transform on the filtered reflection spectrum to obtain a spatial interference intensity waveform. A semiconductor multilayer thin film thickness evaluation apparatus.
束を連続的に照射し、 上記試料によって反射した干渉光束を検出してインター
フェログラムを求め、 このインターフェログラムをフーリエ変換して反射スペ
クトルとし、 この反射スペクトルをフィルタリング処理し、ついで、 フィルタリング処理した反射スペクトルを複素パワー逆
フーリエ変換して空間干渉強度波形とし、この空間干渉
強度波形から上記半導体多層薄膜の各層の膜厚を非破壊
・非接触で評価することを特徴とする半導体多層薄膜の
膜厚評価方法。2. A semiconductor multilayer thin film sample is continuously irradiated with interference light beams having different wave numbers, an interference light beam reflected by the sample is detected to obtain an interferogram, and the interferogram is subjected to Fourier transform to obtain a reflection spectrum. The reflection spectrum is subjected to filtering processing, and then the filtered reflection spectrum is subjected to complex power inverse Fourier transform to obtain a spatial interference intensity waveform. From this spatial interference intensity waveform, the thickness of each layer of the semiconductor multilayer thin film is non-destructively calculated. A method for evaluating the thickness of a semiconductor multilayer thin film, wherein the evaluation is performed in a non-contact manner.
Priority Applications (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24143990A JP2728773B2 (en) | 1990-09-11 | 1990-09-11 | Apparatus and method for evaluating thickness of semiconductor multilayer thin film |
| EP95100378A EP0650030B1 (en) | 1989-09-25 | 1990-09-24 | Apparatus for and method of evaluating multilayer thin films |
| DE69033111T DE69033111T2 (en) | 1989-09-25 | 1990-09-24 | Apparatus and method for the measurement of thin multilayered layers |
| DE69021813T DE69021813T2 (en) | 1989-09-25 | 1990-09-24 | Apparatus and method for the measurement of thin multilayered layers. |
| EP90118322A EP0420113B1 (en) | 1989-09-25 | 1990-09-24 | Apparatus for and method of evaluating multilayer thin films |
| US07/587,114 US5227861A (en) | 1989-09-25 | 1990-09-24 | Apparatus for and method of evaluating multilayer thin film |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24143990A JP2728773B2 (en) | 1990-09-11 | 1990-09-11 | Apparatus and method for evaluating thickness of semiconductor multilayer thin film |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04120404A JPH04120404A (en) | 1992-04-21 |
| JP2728773B2 true JP2728773B2 (en) | 1998-03-18 |
Family
ID=17074327
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP24143990A Expired - Lifetime JP2728773B2 (en) | 1989-09-25 | 1990-09-11 | Apparatus and method for evaluating thickness of semiconductor multilayer thin film |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2728773B2 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05302816A (en) * | 1992-04-28 | 1993-11-16 | Jasco Corp | Semiconductor film thickness measuring device |
| JP3737442B2 (en) * | 2002-03-19 | 2006-01-18 | 日本電信電話株式会社 | Film thickness monitoring apparatus and film thickness monitoring method |
| JP5241321B2 (en) * | 2008-05-20 | 2013-07-17 | 株式会社東京精密 | Wafer polishing state monitoring method and polishing state monitoring device |
| JP6901995B2 (en) * | 2017-06-27 | 2021-07-14 | 株式会社サイオクス | Film thickness measurement method, method for manufacturing nitride semiconductor laminates, and nitride semiconductor laminates |
| JP7112879B2 (en) | 2018-05-15 | 2022-08-04 | 株式会社サイオクス | Method for manufacturing nitride semiconductor laminate, method for inspecting film quality, and method for inspecting semiconductor growth apparatus |
-
1990
- 1990-09-11 JP JP24143990A patent/JP2728773B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04120404A (en) | 1992-04-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5398113A (en) | Method and apparatus for surface topography measurement by spatial-frequency analysis of interferograms | |
| US5227861A (en) | Apparatus for and method of evaluating multilayer thin film | |
| CN110779464A (en) | Time domain and frequency domain joint analysis broad spectrum coherence measurement method and system | |
| US7177029B2 (en) | Stroboscopic interferometry with frequency domain analysis | |
| JP3337734B2 (en) | Infrared ellipsometer | |
| US20100053629A1 (en) | Real-time measurement of ultrashort laser pulses | |
| JP2002005828A (en) | Apparatus and method for inspection of impurity concentration of semiconductor | |
| US10551163B2 (en) | Multi-probe gauge for slab characterization | |
| JPH09119815A (en) | Method and device for measuring film thickness | |
| EP3674698B1 (en) | Inspection apparatus and inspection method | |
| Pikálek et al. | Detection techniques in low-coherence interferometry and their impact on overall measurement accuracy | |
| JPH07508345A (en) | Method and apparatus for inspecting the surface of an object by interferometer | |
| JP2728773B2 (en) | Apparatus and method for evaluating thickness of semiconductor multilayer thin film | |
| CN114894308A (en) | Spectrometer calibration method and system based on low coherence interference | |
| JP2002243416A (en) | Method and instrument for thickness measurement and wafer | |
| JPH07294220A (en) | Method and apparatus for detecting film thickness of multilayered thin film | |
| JPS59105508A (en) | Measurement of whith interference film thickness | |
| JP2005274496A (en) | Component analyzing method and component analysis system using the same | |
| CN110243760B (en) | Line domain frequency domain optical coherence tomography system and longitudinal coordinate calibration method thereof | |
| JPH0652162B2 (en) | Interferometry method | |
| JPS61140806A (en) | Film thickness measuring method | |
| US5805282A (en) | Method and apparatus for coherence observation by interference noise | |
| JPH03110405A (en) | Multi-layered thin film evaluator | |
| JP2002296012A (en) | Film thickness measuring method and film thickness measuring instrument | |
| Wei et al. | Matched filter processing to improve measuring accuracy of interferometric fringe analysis using a multi-pulse train interferometer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FPAY | Renewal fee payment (prs date is renewal date of database) |
Year of fee payment: 10 Free format text: PAYMENT UNTIL: 20071212 |
|
| FPAY | Renewal fee payment (prs date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20081212 Year of fee payment: 11 |
|
| FPAY | Renewal fee payment (prs date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20091212 Year of fee payment: 12 |
|
| FPAY | Renewal fee payment (prs date is renewal date of database) |
Year of fee payment: 12 Free format text: PAYMENT UNTIL: 20091212 |
|
| FPAY | Renewal fee payment (prs date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20101212 Year of fee payment: 13 |
|
| EXPY | Cancellation because of completion of term | ||
| FPAY | Renewal fee payment (prs date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20101212 Year of fee payment: 13 |