Phase transition and microstructure change in Ta-Zr alloy films by co-sputtering

Ta-Zr Thin films with wide range of compositions were deposited on Si (100) substrate by co-sputtering. RF bias power from 0 to 80 W was applied during deposition. Films were then characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and four-point probe. Result showed the incorporation of Zr caused the formation of low-resistivity BCC Ta, which made the resistivity of Ta-Zr films decrease. With substrate bias increasing, the compositional range for forming amorphous structure shrank. The effects of both thermodynamics and kinetics on Ta-Zr amorphization tendency were discussed.