Optical Properties of CuSCN/Stilbazolium Dye Hybrid Thin Films

Authors L.V. Poperenko1, I.V. Yurgelevych1, D.V. Gnatyuk2, K. Uda3, T. Yoshida3

1Taras Shevchenko National University of Kyiv, 64/13, Volodymyrska St., 01601 Kyiv, Ukraine

2V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, 41, prospect Nauky, 03680 Kyiv, Ukraine

3Graduate School of Science and Engineering, Yamagata University, 4-3-16 Jonan, Yonezawa, Yamagata 9928510, Japan

Е-mail vladira_19@ukr.net
Issue Volume 13, Year 2021, Number 6
Dates Received 20 November 2021; revised manuscript received 17 December 2021; published online 20 December 2021
Citation L.V. Poperenko, I.V. Yurgelevych, D.V. Gnatyuk, et al., J. Nano- Electron. Phys. 13 No 6, 06033 (2021)
DOI https://doi.org/10.21272/jnep.13(6).06033
PACS Number(s) 78.68. + m, 81.07.Pr
Keywords Organic-inorganic films, Optical properties (22) , Ellipsometry (5) , Optical anisotropy.

Ellipsometric diagnostics of hybrid organic-inorganic films of copper thiocyanate CuSCN with stilbazolium dye of different concentrations was carried out. The investigated samples with 4-(N,N-dimethyl-amino)-4′-(N′-methyl) stilbazolium tosylate concentrations of 0, 25, 250 and 1000 (mol/dm3 were deposited on F-doped tin oxide substrate. To characterize the optical properties of hybrid organic-inorganic films, the angular dependences of such ellipsometric parameters as the phase shift Δ between p- and s-components of the polarization vector and the azimuth Ψ of the restored linear polarization were measured within a wide range of light incidence angles. Due to their angular dependences, the principal angle (p of light incidence and the value of tg(min were determined. To characterize the electronic properties of the subsurface layers of the investigated hybrid organic-inorganic films, the refractive n and absorption k indices and the optical conductivity ( were defined according to the semi-infinite medium approximation. It was found that an increase in the concentration of stilbazolium dye in hybrid organic-inorganic films from 25 to 250 (mol/dm3 leads to an increase in the principal angle of light incidence and the refractive index. However, the behavior of the ellipsometric parameters of a film with a maximum dye concentration of 1000 μmol/dm3 cannot be explained only by an increase in the dye concentration. It was assumed that this modification of the optical properties of hybrid organic-inorganic films with a maximum dye concentration is associated with a structural phase transition from the rhombohedral (-phase to the orthorhombic α-phase of CuSCN at high dye concentrations, which is confirmed by X-ray diffraction data presented in other works. It is concluded that there is no optical anisotropy of the subsurface layers of the studied samples.

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