Crystallization of In_2Se_3 semiconductor thin films by post-deposition heat treatment. Thickness and substrate effects

摘要

Polycrystalline thin films of γ-In_2Se_3 were grown on various substrates by sequential thermal evaporation of In and Se. The crystallization was achieved by annealing the as-deposited films in flowing nitrogen. The depositions were carried out for different atomic ratios (1.5 less than or equal R = [Se]/[In] less than or equal 5) and the annealings performed at 400 °C for 0.5 h. X-ray diffraction, energy dispersive x-ray analysis, scanning electron microscopy, x-ray photoelectron spectroscopy and Raman scattering have shown that thin films of high crystalline quality were obtained. The influence of the substrate nature as well as the film thickness on the crystallite preferential orientation and size is studied.