Original scientific paper
Structural characterization and optical properties of annealed CdIn2Se4 thin films
A. M. Salem
; Electron Microscopy and Thin Films Department, National Research Centre, Cairo, Egypt
S. H. Moustafa
; Electron Microscopy and Thin Films Department, National Research Centre, Cairo, Egypt
Abstract
CdIn2Se4 chalcogenides thin films were prepared by thermal evaporation process. The effect of thermal annealing in vacuum on the growth characteristics of the deposited films was studied using X-ray and transmission electron microscopy techniques. It was observed that the as deposited films (300 K) were poorly crystalline. The degree of crystallinity increases with increasing the annealing temperature from 300 to 500 K. The compositional elemental analysis of CdIn2Se4 thin films annealed at 500 K was found to be nearly stoichiometric, however, films annealed in vacuum at 575 K partially dissociated into two binary phases with CdIn2Se4 as the major phase. The effect of the annealing temperature on the dispersion of the refractive index of the deposited films was investigated and analyzed within the single effective-oscillator approach. Changes of the dispersion parameters were also investigated as a function of the annealing temperature. Analysis of the optical absorption data revealed the existence of allowed direct and indirect optical transitions, and both values of energy gaps decrease with increasing annealing temperature.
Keywords
CdIn2Se4; thin film; X-ray analysis; TEM; annealing; refractive index; optical absorption
Hrčak ID:
301808
URI
Publication date:
1.10.2004.
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