The optical and electrical properties of the as-prepared and annealed
SnxSb20Se$_{80-x}$ (where x = 8, 10, 12, 13.5, 15, 16.5 and 18
at.%) thin films were studied. X-ray diffraction showed that all the
as-prepared Sn-Sb-Se films were amorphous. Annealing the films at 473 K or
above crystallized the films and the degree of crystallinity depended on the
Sn content. The optical transmittance and reflectance were measured in the
wavelength rang 200–2500 nm. The estimated optical band gap was found to
decrease with increasing Sn content. A great difference in the optical
constants values due to transformation from amorphous to crystalline phase
structure of the films were found after annealing. This is advantageous for
optical disk data storage applications. It was found that the resistivity
decreases with increasing temperature for all the compositions indicating
that these films have a semiconducting behavior with thermally activated
conduction. The conduction in these films was suggested to be thermally
assisted charge carrier movement in the extended states. Annealing the films
caused a reduction in the room temperature resistivity by six order of
magnitude. This was ascribed to the amorphous-crystalline transformation.