Structure and Electroconductivity of the Nanocrystalline CoNi Thin Film Alloys

Structure, phase composition and electroconductivity of nanocrystalline CoNi thin film alloys are investigated. During the I-st cycle of thermal stabilization the grain size increases from approximately 5 nm to 110-200 nm. Films with Co content less than 70 mass % have the single-phase composition with the fcc-lattice. Increase in the lattice parameter, which can be described by the Vegard's rule, is observed with the growth of Co concentration. At Co content more than 75 mass % the annealed films have the two-phase fcc-hcp composition. Quadratic temperature dependence of the resistivity, which is also observed for the single-layer films of pure ferromagnetic metals, is inherent to the films of a given alloy. Using analysis of the size dependences of electroconductivity the concentration dependence of the resistivity is plotted.