Proceedings of the
9th International Conference of Asian Society for Precision Engineering and Nanotechnology (ASPEN2022)
15 – 18 November 2022, Singapore

Dual Dispersive Interferometric Probe System for Measuring Double-Sided Film Structures

Joonho You1, Uihyeok Kwon2 and Ki-Nam Joo2,a

1Nexensor, 3-404,407, 70, Yuseong-daero 1689beon-gil, Yuseong-gu, Daejeon, 34047, South Korea

2Dept. of Photonic Engineering, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju, 61452, South Korea


In this investigation, we design a dual optical probe system to measure double-sided film structure similar to a pouch-type secondary battery cell. By adopting the dispersive interferometric principles, the optical path difference between the reference and measurement arms can be determined by the phase slope of the spectral interferogram without any mechanical movement. Therefore, the measurement probe can measure the surface positions on each side of the specimen, and the geometrical relationship between two probes enables to determine the whole thickness of the specimen, substrate thickness and film thicknesses at once. As the experimental results, the physical thickness of the cover glass was measured to evaluate the system performance, and a pouch-type secondary battery cell was measured as a double-sided film structure with sub-micrometer precision.

Keywords: Dispersive interferometry, Dual optical probe system, Double-sided film structure

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