【公開日：2023.07.31】【最終更新日：2023.05.15】
課題データ / Project Data
課題番号 / Project Issue Number
22UT0438
利用課題名 / Title
熱放射薄膜の表面分析
利用した実施機関 / Support Institute
東京大学 / Tokyo Univ.
機関外・機関内の利用 / External or Internal Use
内部利用（ARIM事業参画者以外）/Internal Use (by non ARIM members)
技術領域 / Technology Area
【横断技術領域 / Cross-Technology Area】（主 / Main）計測・分析/Advanced Characterization（副 / Sub）-
【重要技術領域 / Important Technology Area】（主 / Main）革新的なエネルギー変換を可能とするマテリアル/Materials enabling innovative energy conversion（副 / Sub）-
キーワード / Keywords
Optical constant, Thin film, Thermal radiation, Spectroscopic ellipsometry
利用者と利用形態 / User and Support Type
利用者名（課題申請者）/ User Name (Project Applicant)
李 禮林
所属名 / Affiliation
東京大学
共同利用者氏名 / Names of Collaborators in Other Institutes Than Hub and Spoke Institutes
Jiang Guo
ARIM実施機関支援担当者 / Names of Collaborators in The Hub and Spoke Institutes
利用形態 / Support Type
（主 / Main）機器利用/Equipment Utilization（副 / Sub）-
利用した主な設備 / Equipment Used in This Project
報告書データ / Report
概要（目的・用途・実施内容）/ Abstract (Aim, Use Applications and Contents)
Ellipsometry is a non-destructive technique that is used to measure the thickness and optical properties of thin films. In this study, a spectroscopic ellipsometer was used to measure the thickness and optical constant data of a SiO2 thin film on a silicon substrate.
実験 / Experimental
The 200nm SiO2 thin film is deposited on silicon substrate by RF Magnetron sputtering process. The spectroscopic ellipsometer (J.A. Woollam, M2000) was used to measure the thickness and optical constant data of the SiO2 film. The instrument uses a polarized light source that is directed at the sample at fixed angles (60, 65, 70 deg.). The light that is reflected from the sample is analyzed by the instrument, which provides information on the thickness and optical constant data of the film.
結果と考察 / Results and Discussion
The spectroscopic ellipsometer was used to
measure the optical constants of a silicon dioxide (SiO2) thin film
on a silicon substrate. Two models were utilized for the analysis: the Cauchy
model and the B-spline model.
For the Cauchy model, the optical constants
of the SiO2 thin film were calculated based on a simple dispersion
formula. The model assumes a linear relationship between the refractive index
and wavelength, which is valid for materials with relatively simple structures.
The results in Figure 1 showed that the refractive index (red line) and extinction
coefficient (blue line) of the SiO2 thin film were indicated by dash
dot lines in the figure respectively.
The B-spline model, on the other hand,
assumes a non-linear relationship between the refractive index and wavelength,
which is more suitable for materials with complex structures. The model was
used to fit the experimental data obtained from the ellipsometer measurements,
and the results showed that the refractive index (red line) and extinction
coefficient (blue) of the SiO2 thin film were indicated by dot lines in the
figure respectively.
Comparing with literature data of SiO2
optical constant (solid line in the figure), the measure refractive index is a
bit higher in the measurement wavelength range, the extinction coefficient
result by B-spline model is not zero in the near infrared range. Overall, the spectroscopic
ellipsometer was effective in measuring the optical constants of the SiO2
thin film on a silicon substrate. The use of both the Cauchy and B-spline
models provided more accurate results and a better understanding of the optical
properties of the film.
図・表・数式 / Figures, Tables and Equations
Figure 1. SiO2 optical constant fitted by Cauchy model (dash dot), B-spline model (dot) and Palik book(1)
その他・特記事項（参考文献・謝辞等） / Remarks(References and Acknowledgements)
(1) Handbook of Optical Constants of Solids. Orlando :Academic Press, 1985. · APA. edited by Edward D. Palik. (1985).
成果発表・成果利用 / Publication and Patents
論文・プロシーディング（DOIのあるもの） / DOI (Publication and Proceedings)
口頭発表、ポスター発表および、その他の論文 / Oral Presentations etc.
特許 / Patents
特許出願件数 / Number of Patent Applications：0件
特許登録件数 / Number of Registered Patents：0件