Deposition rate– dependent transition of growth mechanisms in Zr 60 Ni 30 Al 10 metallic glass thin films

In this study, Zr 60 Ni 30 Al 10 metallic glass thin films were deposited by DC magnetron sputtering over a deposition rate range of 5–32 nm/min to investigate the relationships between deposition conditions, growth kinetics, structural evolution, and mechanical behavior. The results reveal a distinctly non-monotonic evolution of the amorphous structure across the investigated deposition conditions, indicating changes in the prevailing growth behavior during film formation. Films deposited at low deposition rates exhibited relatively stronger structural ordering, larger and more uniformly distributed surface features (∼111 nm), smoother surface morphology, and superior mechanical performance, with hardness values reaching ∼9.1 GPa. Under intermediate deposition-rate conditions, the films developed finer surface features (∼42–59 nm), increased surface roughness, and reduced hardness and elastic modulus, consistent with more kinetically constrained growth and restricted atomic relaxation. Interestingly, under the highest deposition-rate condition, the films exhibited partial structural recovery rather than continued disordering. This recovery was accompanied by a bimodal surface feature morphology, partial surface stabilization, substantial recovery of medium-range order (MRO), and near-complete recovery of the elastic modulus, whereas short-range order (SRO) and hardness recovered only partially. The different recovery behaviors of MRO and SRO suggest that distinct structural length scales respond differently to the associated high-flux growth conditions and contribute differently to the elastic and plastic responses of the films. Overall, the results demonstrate that changes in deposition conditions modify the balance between structural relaxation and kinetic constraints through the associated growth kinetics, thereby influencing atomic ordering, surface morphology, and structure–property relationships in metallic glass thin films.