Applied Surface Science, Vol.255, No.24, 9691-9694, 2009
Spectroscopic studies of (AsSe)(100-x)Ag-x thin films
Thin (AsSe)(100-x)Ag-x films have been grown onto quartz substrates by vacuum thermal evaporation or pulsed laser deposition from the corresponding bulk materials. The amorphous character of the coatings was confirmed by X-ray diffraction investigations. Their transmission was measured within the wavelength range 400-2500 nm and the obtained spectra were analyzed by the Swanepoel method to derive the optical band gap E-g and the refractive index n. We found that both parameters are strongly influenced by the addition of silver to the glassy matrix: E-g decreases while n increases with Ag content. These variations are discussed in terms of the changes in the atomic and electronic structure of the materials as a result of silver incorporation. (C) 2009 Elsevier B.V. All rights reserved.