Microstructural characterisation of electrodeposited Co/Pt multilayers

We have prepared Co/Pt multilayers by electrolysis using a potentiostatic t echnique. The solution is based on CoSO4.7H(2)O and K2PtCl6 salts. Our film s with periods of(0.8-15) nm have been characterised using X-ray diffractio n, electron diffraction analysis of X-rays, scanning electron microscopy an d torque magnetometry. Perpendicular magnetic anisotropy was observed for m ultilayers with Co layers thinner than about 1.0 nm, and a Pt layer thickne ss of 1.0 nm. A simultaneous multinuclear growth of grains of ordered phase s (L1(0)) CoPt or (L1(2)) CoPt3, depending on the electrolysis parameters f ormed films with very short periodicity. In films with bilayer period thick er than 2.5 nm, polycrystalline h.c.p. Co layers are successive stacked wit h amorphous Pt layers. Effective magnetic anisotropy per unit volume and co ercive field were found to depend on Co layer thickness (t(Co)) for a serie s of Co/Pt multilayers with t(Pt) = 1 nm and t(Co) varying in the range (0. 3-4) nm. (C) 2000 Published by Elsevier Science S.A. All rights reserved.