Thin-film thickness measurement with normal spectral reflectance

Jiao Bai; Haowei Yang; Junguang Chen; Yinke Liu; Jiangfeng Song; Yan Shi

doi:10.1117/12.2684208

27 November 2023 Thin-film thickness measurement with normal spectral reflectance

Jiao Bai, Haowei Yang, Junguang Chen, Yinke Liu, Jiangfeng Song, Yan Shi

Proceedings Volume 12771, Advanced Sensor Systems and Applications XIII; 1277117 (2023) https://doi.org/10.1117/12.2684208
Event: SPIE/COS Photonics Asia, 2023, Beijing, China

Conference Poster

Abstract

Thin films are used in many areas for protecting the base, isolating electrons, and so on. Based on the thin-film interference principle and the characteristics of Y-shaped fiber, this paper proposed a reflection objective with annular reflection. With the objective, incident light from the central fiber can be well received for high signal-to-noise ratio. By comparing with the prior-known spectral reflectance of the standard mirror, the absolute spectral reflectance of the thin-film can be achieved. Furthermore, according to the spectral reflectance of the thin-film, film thickness is acquired by the evolutionary genetic algorithm. In the algorithm, the thickness is taken as the independent variable, and the squared difference between the measured spectral reflectance and the preset theoretical spectral reflectance is set as the goal to carry out the global optimization. By testing different silicon-based silica films, the measurement results proved high feasibility and good global fitness. And the total measurement time of a single point is less than 1s. In conclusion, the thin-film measurement system based on the proposed reflection objective and inversion algorithm own excellent performance, which is hopeful for broad usage.

(2023) Published by SPIE. Downloading of the abstract is permitted for personal use only.

Citation Download Citation

Jiao Bai, Haowei Yang, Junguang Chen, Yinke Liu, Jiangfeng Song, and Yan Shi "Thin-film thickness measurement with normal spectral reflectance", Proc. SPIE 12771, Advanced Sensor Systems and Applications XIII, 1277117 (27 November 2023); https://doi.org/10.1117/12.2684208

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available