Structural and optical properties of CuSe sub(2) nanocrystals formed in thin solid Cu-Se film

• Published in: Infrared physics & technology 2016-05, Vol.76, p.276-284
• Main Authors: Gilica, M, Petrovica, M, Kostica, R, Stojanovica, D, Barudzijab, T, Mitricb, M, Romcevica, N, Ralevica, U, Trajica, J, Romcevica, M, Yahiac, I S
• Format: Article
• Language: English
• Subjects: Atomic force microscopy; CRYSTAL STRUCTURE; Doppler effect; Inclusions; MATHEMATICAL ANALYSIS; Mathematical models; Nanocrystals; Optical properties; PROPERTIES; Scanning electron microscopy; THIN FILMS
• ISSN: 1350-4495
• DOI: 10.1016/j.infrared.2016.03.008

This paper describes the structural and optical properties of Cu-Se thin films. The surface morphology of thin films was investigated by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Formation of Cu-Se thin films is concluded to proceed unevenly, in the form of islands which later grew into agglomerates. The structural characterization of Cu-Se thin film was investigated using X-ray diffraction pattern (XRD). The presence of two-phase system is observed. One is the solid solution of Cu in Se and the other is low-pressure modification of CuSe sub(2). The Raman spectroscopy was used to identify and quantify the individual phases present in the Cu-Se films. Red shift and asymmetry of Raman mode characteristic for CuSe sub(2) enable us to estimate nanocrystal dimension. In the analysis of the far-infrared reflection spectra, numerical model for calculating the reflectivity coefficient of layered system, which includes film with nanocrystalite inclusions (modeled by Maxwell-Garnett approximation) and substrate, has been applied.