Preparation of CoB Soft Magnetic Thin Films by Eleetroless Plating

Eleetroless plated CoB films were plated in a bath with dimethylamineborane (DMAB) as a reducing agent. The magnetic properties of films changed widely with changes in the concentration of the complexing agent in the bath, such as ammonium sulfate or sodium tartrate. Film with the lowest coercivity was obtained from the bath containing 0.3 mol/dm³ of sodium sulfate and 0.55 mol/dm³ of sodium tartrate. Structural analysis of this film by electron microscopy revealed that the film consists of fine, highly crystalline particles with the hep structure.