Preparation of Co–W–P alloy films by pulse plating

Abstract

Co–W–P films were prepared by a pulse plating method on a copper substrate. Effects of different duty ratios on composition, microstructure and magnetic properties of films were investigated. With the increase in duty ratios, the deposition speed increased gradually during the pulse plating process. It was found that the higher ratio duty could improve contents of cobalt and reduce amounts of phosphorus in the film. Almost all the deposited films were crystalline and formed tetrahedral structures Co₃W with preferred crystallographic orientation (200) and (201). Dissimilar surface morphology could be detected under different duty ratios. Atomic force microscopy showed that lower duty ratios could form typical nodular structures and the dense surface. However, the films with rough and agglomerate nodular structures would be detected with higher duty ratios. Vibration sample magnetometer results showed that higher duty ratio induced larger saturation magnetisation and lower coercivity of Co–W–P films.