Preparation of Co–Pt–P thin films by magnetic electrodeposition

Abstract

Magnetic fields perpendicular to the electric field were applied during an electrodeposition process to obtain Co–Pt–P thin films from alkaline baths. Effects of different current densities and magnetic intensities on the composition, microstructure and magnetic properties of Co–Pt–P thin films were studied. It was found that the deposition rate and films thickness increased gradually with the increase of the current density and magnetic intensity. Almost all of the deposited films were crystalline and showed Co(002), CoPt(111) peaks. With the increase in the magnetic intensity, the intensity of CoPt(111) peak decreased while the intensity of Co(002) rose gradually. Magnetic fields would induce cobalt growing along (002) orientation. The films were densely covered with typical nodular structure. When the current density increased to 100 A m−2, rougher and agglomerate nodular structures would be formed. Films of smaller grain size and smooth surface could be formed under high magnetic intensity (0·5 T) as a result of impact of magnetic force and MHD effects. Furthermore, higher current density induced larger Magnetisation and lower coercivity. Largest coercivity could be achieved when current density equals to 70 A m−2. With the increase in magnetic intensity, cobalt contents in films increase gradually which lead to the rise on magnetisation.