Stress and microstructure of nanocrystalline FeXN (X=Ta, Si, and Al) thin films

Magnetic domain structures in thin-film heads are influenced by magnetoelastic anisotropy which is proportional to the film stress. In this study we have undertaken systematic measurements of thin film stress in the as-deposited state for sputtered FeXN (X = Ta, Si, and Al) thin films as a Function of Ta, Si, Al, and N content. All as-deposited films exhibited the alpha-Fe structure with a (110) growth texture. It was found that pure Fe exhibits a tensile stress and this stress becomes more compressive as the amounts of Ta, Si, Al, and N in the films are increased. These stresses appear to be a cumulative effect of the amounts of Ta, Si, Al, and N added to the pure Fe, It was also found that N decreases the biaxial modulus of FeN and Fe-10TaN thin films.