Solution processed Ge20Sb5S75 thin films: the effect of solution concentration and multiple layers stacking

Abstract

Ge20Sb5S75 thin films with high chemical resistance to aliphatic amines were deposited from solutions of various glass concentrations (0.015-0.09 g of grinded glass material/ml of n-butylamine) by the spin-coating technique. As-prepared and annealed thin films were analyzed by spectroscopic ellipsometry and EDS (energy-dispersive X-ray spectroscopy). Results proved that the refractive index of thin films was not affected by the solution concentration (within studied range), and the studied optical properties of deposited samples were homogenous in their volume. The Ge20Sb5S75 solution of the highest concentration (0.09 g/ml) was chosen for deposition of thicker chalcogenide glass material using multiply deposition/thermal stabilization procedure. Prepared multilayers proved to have good optical quality and homogenous chemical resistance through the whole thickness. No interfaces between layers were observed from etching kinetics and SEM scans. Thus, the results confirmed that multiple layers stacking procedure is suitable for deposition of thick homogenous Ge20Sb5S75 thin films.