УДК: 53.097, 532.016, 535.15, 535.557, 537.9

The orientation of liquid crystals on obliquely deposited layers of SiO2 and CeO2

Amosova, L.P., Parfenov, P.S., Isaev, M.V.

Publication in Journal of Optical Technology

For Russian citation (Opticheskii Zhurnal):

Амосова Л.П., Парфенов П.С., Исаев М.В. Ориентация жидких кристаллов на наклонно напыленных слоях SiO2 и CeO2 // Оптический журнал. 2014. Т. 81. № 11. С. 88–95.

Amosova L.P., Parfenov P.S., Isaev M.V. The orientation of liquid crystals on obliquely deposited layers of SiO2 and CeO2 [in Russian] // Opticheskii Zhurnal. 2014. V. 81. № 11. P. 88–95.

For citation (Journal of Optical Technology):

L. P. Amosova, P. S. Parfenov, and M. V. Isaev, "The orientation of liquid crystals on obliquely deposited layers of SiO₂ and CeO₂," Journal of Optical Technology. 81(11), 686-691 (2014). https://doi.org/10.1364/JOT.81.000686

Abstract:

The surface texture is compared for silicon oxide and cerium oxide films obtained by oblique laser deposition at identical angles and deposition rates. This paper discusses how the crystallization tendency of the oxides affects the structure and relief of the deposited film—the length and tilt angle of the resulting columnar crystals to the substrate and the presence or absence of ridges of crystallites extended in a direction perpendicular to the deposition direction. The main types of surface relief formed by oblique deposition of oxides are considered, along with the various ways the liquid crystals are oriented by means of these reliefs. It is shown that the ratio of the sizes of the liquid-crystal molecules and the characteristic inhomogeneities of the surface relief serve as the main criterion for their longitudinal or transverse orientation, since orientation with a small contact area is energetically unfavorable.

Keywords:

liquid crystals, orientation, silicon and cerium oxides, oblique deposition, surface relief

Acknowledgements:

This work was carried out with state financial support of the leading universities of the Russian Federation (Subsidy 074-U01) and the internal facilities of the St. Petersburg National Research University of Information Technologies, Mechanics, and Optics.

OCIS codes: 230.3720, 160.3710

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