Open AccessThermal-induced optical changes in the amorphous Ge20Sb15Se65 film
Author(s) -
Zong Shuang-Fei,
Xiang Shen,
Tao Xu,
Yu Chen,
Guoxiang Wang,
Fen Chen,
Jun Li,
Changgui Lin,
Qiuhua Nie
Publication year - 2013
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.62.096801
Subject(s) - amorphous solid , materials science , raman spectroscopy , refractive index , thin film , band gap , sputter deposition , annealing (glass) , analytical chemistry (journal) , spectroscopy , glass transition , sputtering , optics , optoelectronics , crystallography , nanotechnology , composite material , chemistry , polymer , physics , chromatography , quantum mechanics
The amorphous Ge20Sb15Se65 thin film was prepared by magnetron sputtering deposition technique. Effect of heat treatment temperature in the range of 150—400 ℃ on the optical properties of Ge20Sb15Se65 thin films has been investigated. The microstructure and optical properties of the films were characterized by UV-Vis, Raman spectroscopy and XRD, the optical constant was calculated using the Swanepoel method and Tauc's law from the optical transmission spectra. Results indicate that when the annealing temperature (Ta) is lower than the glass transition temperature (Tg), the optical band gap (Egopt) increases from 1.845 to 1.932 eV, and the refractive index decreases from 2.61 to 2.54, while the optical band gap decreases from 1.932 to 1.822 eV and the refractive index increases from 2.54 to 2.71 with a further increase of Ta. The results were explained in terms of the Mott and Davis model for amorphous materials and amorphous to crystalline structural transformations. It is well consistent with the results of structure analysis by XRD and Raman spectroscopy.