Magnetic force microscopy study of magnetization reversal in sputtered FeSiAl(N) films

The magnetization reversal in a series of rf-sputtered FeSiAl(N) films has been studied using magnetic force microscopy. A system has been developed w hich has the capability to image domain structure while an in-plane magneti c field is applied in situ. All films exhibited a stripe domain structure i n zero applied field which was indicative of a perpendicular component of d omain magnetization which alternates in sign. All films showed a similar se quence of magnetization processes: on reducing the applied field from satur ation a fine stripe domain structure nucleated and then coarsened as the fi eld was decreased to zero. Local switching of domain contrast was observed along the steepest part of the hysteresis loop as the perpendicular compone nt reversed. As the reverse field was increased toward saturation, the stri pe domains disintegrated into smaller regions. This observation is consiste nt with an interpretation that the domain magnetization rotated locally int o the sample plane. The saturation field and the film stress exhibited simi lar trends with nitrogen partial pressure. The results suggest that the per pendicular anisotropy that caused the formation of the stripe domain struct ure could be induced by the film stress via magnetoelastic coupling. (C) 20 01 American Institute of Physics.