Open AccessAnnealing Effect on Optical properties of (As0.5Se0.5 doped with 1% Te) thin films
Author(s) -
Rusul Adnan Al-Wardy
Publication year - 2018
Publication title -
almustansiriya journal of pharmaceutical sciences/al-mustansiriyah journal of pharmaceutical sciences
Language(s) - English
Resource type - Journals
eISSN - 2959-183X
pISSN - 1815-0993
DOI - 10.32947/ajps.v18i1.463
Subject(s) - materials science , annealing (glass) , absorption edge , amorphous solid , doping , thin film , transmittance , band gap , analytical chemistry (journal) , vacuum evaporation , nanotechnology , optoelectronics , composite material , crystallography , chemistry , chromatography
this work, the study of optical properties of (As0.5Se0.5 doped with 1% Te) thin films which prepared by thermal vacuum evaporation on glass bases at (R.T) with (100±20)nm thickness deposition rate (1.6nm/s) and study effect of annealing at temperatures (Ta) (348,398,448)K for time (30min) on these properties. The X-ray diffraction technique showed that all prepared films are amorphous in structure at room temperature and annealing films at (348, 398, 448)K. The transmittance spectra of the prepared films falls within a wavelength range (500-1100) nm, and increasing the annealing temperature leads to a decreased in transmission, increased absorption coefficient, and shift of the absorption edge towards low photon energies. The optical measurements showed that the prepared films had an allowed indirect optical energy gap and were found to decrease with the increase of (Ta) within the range (R.T, 348,398,448) K. As indicated by the tails of the localized states, it was observed that they increased by increasing (Ta).