Substrate bias effect on magnetic properties of sputter deposited Co/Pt multilayers.

Abstract

Co/Pt multilayered films were prepared by RF sputtering method with negative substrate bias (VB). The film morphology of the multilayers changes from the columnar structure to the fine structure by the application of VB. A bias voltage of about −30 V improves the flatness and sharpness of the interface, and causes a decrease in the perpendicular coercivity, because of the reduction of the pinning effect at the layer surfaces or the column boundaries. In the biased films with low coercivity, the stripe domains were clearly observed by the Bitter method.