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FIZIKA A 13 (2004) 4 , 137-150
 
STRUCTURAL CHARACTERIZATION AND OPTICAL PROPERTIES OF ANNEALED CdIn2Se4
THIN FILMS
A. M. SALEMa,1 and S. H. MOUSTAFAb
aElectron Microscopy and Thin Films Department, National
Research Centre, Cairo, Egypt
bHelwan University, Faculty of Science, Cairo, Egypt
1E-mail address: Salemar55@hotmail.com
Received 24 April 2004; Accepted 20 December 2004
Online 2 February 2005
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.
PACS numbers: 68.55.-a, 68.60.Dv, 68.90.+g
UDC 538.975
Keywords: CdIn2Se4, thin film, X-ray analysis, TEM, annealing,
refractive index, optical absorption
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