Tracking the thermostimulated transformations of silicon suboxide film through absorption edge characterization

In this work, the structural transformations of a suboxide vacuum-deposited film of SiO1.3 composition annealed in an inert atmosphere in a wide temperature range of 100 °C–1100 °C were characterized by the reflection-transmission spectroscopy technique. The experimental spectroscopic data were used to obtain the spectra of the absorption coefficient α(hν)in the absorption edge region of the film. Based on their processing, the dependences of Urbach energy EU and optical (Tauc) bandgap Eo on the annealing temperature were obtained. An assessment of the electronic band gap (mobility gap) Eg was also carried out. Analysis of these dependences allowed us to trace dynamics of thermally stimulated disproportionation of the suboxide film and the features of the formation of nanocomposites consisting of amorphous and/or crystalline silicon nanoparticles in an oxide matrix.