Physico-Chemical nanomaterials science

Growth, crystal structure and theoretical studies of energy and optical properties of CdTe1-xSex thin films
Kashuba A.I.1, Ilchuk H.A.1, Petrus R.Yu.1, Andriyevsky B.2, Semkiv I.V.1, Zmiyovska E.O.1
1Department of General Physics, Lviv Polytechnic National University, S. Bandera Str., 12, Lviv-79013, Ukraine.
2Faculty of Electronics and Computer Sciences, Koszalin University of Technology, Sniadeckich str. 2, 75-453 Koszalin, Poland.
E-mail: AndriyKashuba07@gmail.com

Thin films of cadmium chalcogenides (CdX, X= S, Se and Te) representative of AIIBVI crystal group and shows semiconductor behavior. They are an important research field because of their wide application in various fields of optoelectronic devices [1].
CdTe1-xSex (CTS) thin film was prepared by quasi close-space sublimation method. The glass substrates were ~14 mm in diameter were used for deposition CTS thin films. Before the films deposition, the substrate surface was cleaned by boiling in a high purity CCl4 solution during 0.5 h.
The phase analysis and crystal structure refinement was examined with using X-ray diffraction data. CTS thin film crystallize in cubic structure (structure type –ZnS, space group F-43m, with unit-cell constants a= 6.395(3) Å and V= 261.6(4) Å3). Chemical composition of the films was examined using energy dispersive spectroscopy (EDS).
The theoretical calculations of band energy structure were performed within the framework of the density functional theory (DFT). The electron energies and concentrations were determined from the Kohn–Sham equations. The method of generalized gradient approximation (GGA) was used to describe the exchange-correlation potential. The representation of this potential was taken in the Perdew–Burke–Ernzerhof (PBE) form. The models of CTS films were formed from a three-dimensional CTS crystal. Using the Kramers–Kronig relations, optical functions are obtained.

1.	Petrus R.Yu., Ilchuk H.A., Kashuba A.I., Semkiv I.V., Zmiiovska E.O., Lys R.M. Optical properties of materials for solar energy based on cadmium chalcogenides thin films // Physics and Chemistry of Solid State.–2019.–20, N 4.–P. 367–371.