CHARACTERIZATION OF PERMALLOY THIN-FILMS ELECTRODEPOSITED ON SI(111) SURFACES

The electrochemical conditions for the direct electroplating of Ni-Fe Permalloy (19% Fe, 81% Ni) thin films onto Si(111) surfaces were deter mined. The film composition, structure, and magnetic properties were e xamined by various techniques involving Auger electron spectroscopy de pth profiles analysis, scanning electron microscopy, transmission elec tron microscopy, atomic force microscopy, and magneto-optic Kerr effec t measurements. The Permalloy films consisted of 10-50-nm-diam Ni/Fe n anocrystallites. It was found;hat the coercivity decreased with increa sed film thickness. Moderate annealing of the films below 200 degrees C released stress in the films and led to a decrease in coercivity. In terfacial diffusion occurred after the annealing of films above 300 de grees C. The Ni-Fe films exhibited bulk properties after the completio n of electrodeposition of a buffer layer of thickness >20 nm; below th is thickness, the films were discontinuous and consisted of separated clusters or islands on the Si surface. (C) 1997 American Institute of Physics.