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arXiv · 2402.15249

Interferometric microscale measurement of refractive index at VIS and IR wavelengths

Meguya Ryu·Simonas Varapnickas·Darius Gailevicius·Domas Paipulas·Eulalia Puig Vilardell·Zahra Khajehsaeidimahabadi·Saulius Juodkazis·Junko Morikawa·Mangirdas Malinauskas
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Abstract

Determination of refractive index of micro-disks of a calcinated ($1100^\circ$C in air) photo-resist SZ2080$^\mathrm{TM}$ was carried out using transmission and reflection spectroscopy. Interference fringes at specific wavenumbers/wavelengths were selected for determination of the optical thickness, hence, the refractive index when the thickness of micro-disks was measured by scanning electron microscopy (SEM). Refractive index of disks of $\sim 6\pm 1~\mu$m thickness were determined at visible and IR (2.5-13~$\mu$m) spectral ranges and where $2.2\pm 0.2$ at visible and IR wavelengths. Peculiarities of optical characterisation of micro-optical structures are discussed in view of possible uncertainties in the definition of geometric parameters, shape and mass density redistribution.

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Meguya Ryu, Simonas Varapnickas, Darius Gailevicius, Domas Paipulas, Eulalia Puig Vilardell, Zahra Khajehsaeidimahabadi, Saulius Juodkazis, Junko Morikawa, Mangirdas Malinauskas. 2024-02-23. Interferometric microscale measurement of refractive index at VIS and IR wavelengths. https://arxiv.org/abs/2402.15249

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