Physical investigations on (In2S3)x(In2O3)y and In2S3−xSex thin films processed through In2S3 annealing in air and selenide atmosphere

Abstract In 2 S 3− x Se x and (In 2 S 3 ) x (In 2 O 3 ) y thin films have been prepared on glass substrates using appropriate heat treatments of In evaporated thin films. X-ray analysis shows that In thin films which were annealed under sulfur atmosphere at 350 °C were mainly formed by In 2 S 3 . A heat treatment of this binary in air at 400 °C during one hour leads to (In 2 S 3 ) x (In 2 O 3 ) y ternary material which has a tetragonal structure with a preferred orientation of the crystallites along the (109) direction. Similarly, a heat treatment of In 2 S 3 in selenium atmosphere at 350 °C during six hours leads to a new In 2 S 3− x Se x ternary material having tetragonal body centered structure with a preferred orientation of the crystallites along the (109) direction. Optical band gap, refractive index and extinction coefficient values of In 2 S 3− x Se x and (In 2 S 3 ) x (In 2 O 3 ) y thin films have been reached. Moreover, correlations between optical conductivity, XRD, AFM and Urbach energy of such ternary thin films have been discussed. Finally, the recorded formation disparity between the quaternary (In 2 S 3 ) x (In 2 O 3 ) y and ternary In 2 S 3− x Se x compounds has been discussed in terms of the Simha–Somcynsky and Lattice Compatibility theories.