The influence of sputtering power on phase-change films

Sputter-deposited amorphous films of a phase-change material (Ge ₂Sb ₂Te ₅) were prepared with various magnetron sputtering powers to determine its influence. Microscopic characteristics indicate that the sputtering power affects the film morphology: high sputtering powers lead to inhomogeneous domain-like patterns. The transition temperature from a metastable phase to a hexagonal phase decreased as the sputtering power increased. However, an analysis of the radial distribution functions indicates that the sputtering power did not have a distinct influence on the inner atomic structure of the amorphous phase. Therefore, a low sputtering power is beneficial to improve the quality of sputtered amorphous films.