Grain boundary amorphization reaction in thin films of elemental Cu and Y

摘要

Compositionally modulated thin films of Cu and Y were prepared in an ultrahigh vacuum dc ion beam deposition chamber. Room‐temperature growth of an amorphous Cu‐Y phase was observed with interdiffusion of the elemental Cu and Y. Transmission electron microscopy of as‐prepared samples revealed a novel growth morphology; amorphous phase formation was observed both at the original Cu/Y interface and between the grains of the elemental Y. Estimates for the thermodynamic and kinetic factors underlying the grain boundary amorphization reaction are presented.