  Here we report on studying the electronic and optical material properties of
the technologically-relevant material indium tin oxide (ITO) as a function of
thermal annealing. In this work, ITO powder has been prepared utilizing
solid-state reaction methods. An electron beam gun technology has been used to
prepare a ITO film (325 nm). The ITO window layer has been investigated at
various temperatures. The effects of absolute temperature on the structural,
optical, and electrical properties of the prepared ITO thin film layer are
investigated. The energy band type corresponding to the orbital transitions has
been determined, and the energies of the orbital transitions have been
calculated in the Tauc region, HOMO/LUMO gap, and charge transfer gap. In
additions, the exciton and Urbach energies have been computed. It has been
found that these energies increase with increasing the annealing temperature,
except for Urbach's energies which behave differently. Thin-film quality
coefficient, surface resistance, and thermal emission in addition to the angle
of refraction as a function of wavelength, have been determined.
