Thermal Annealing Induced Modifications on the Structural and Optical Properties of AgInSe_2 Thin Film

摘要

In the present study, 300 nm thick films of AgInSe_2 were prepared by selenization of the multilayer of Ag/In/Ag/In deposited by DC magnetron sputtering. Selenization was done at the 300 C and a few of the selenized film were annealed at 500 C. The films were characterized by X-ray diffraction (XRD) and UV-Visible-NIR spectroscopy. XRD revealed the presence of about 24 vol% of Ag_2Se as impurity phase in the AgInSe_2 films, which were only selenized. Annealing of the selenized films at 500 C suppressed the impurity phase to about 5 vol%. Annealing also led to increase of crystallite size and improvement of crystallinity. Associated with the suppression of the impurity phase, the band gap of the film was found to increase on annealing at 500 C.