Solution processed multi-layered thin films of GeSbS and GeSbSe chalcogenide glasses.

Solution processed non-toxic GeSbSe chalcogenide glass thin films were deposited using spin-coating method from n-propylamine-methanol solvent mixture in specular optical quality. Optical properties, composition, structure, and chemical resistance were studied in dependence on the annealing temperature. Significant increase of refractive index and chemical resistance caused by thermoinduced structural polymerization and release of organic residua were observed. The high chemical resistance of hard-baked thin films allowed repeated direct depositions by spin-coating, increasing total thickness. Multilayered thin films of amorphous GeSbSe and GeSbS were also successfully prepared by direct deposition for the first time. Solution based deposition of non-toxic GeSbSe thin films in specular optical quality significantly widens the applicability of solution processed chalcogenide glass thin films. Moreover, solution based direct deposition of different glasses on hard-baked thin films opens the way to simple and cost-effective preparation of more sophisticated optical elements (e.g. beam splitters, photonic mirrors).