Smooth transparent amorphous layers based on a zinc-tin-oxide composite system

Smooth amorphous oxide thin films were obtained by using rf magnetron sputtering of ceramic targets based on a mixture of zinc and tin oxides (ZTO). The influence of the target composition, oxygen content in the working gas, and film thickness on the morphology, structure, and optical characteristics of low-temperature deposited ZTO films has been studied. The minimum relief is observed in films obtained by sputtering a target with equal molar contents of zinc and tin oxides. When using this target, some polishing effect is found when the surface roughness of the Si substrate with an ultrathin ZTO layer (up to 15 mm of thickness) is less than that of the original Si substrate.