The dependence of magnetic properties on crystallographic structure of electrochemically deposited Ni/Cu superlattices

Ni/Cu superlattices have been grown by electrodeposition from a single sulfamate bath (based on Ni(SO₃NH₂)₂ and CuSO₄) by using the potentiostatic method. Chemical composition of single layers was investigated with SIMS. The Cu layers were almost pure (99.85% Cu) while Ni layers contained 2 ÷ 5% Cu. The lambda period (L) and crystallographic structure of the superlattices were established by X-ray investigations. Good quality of the Ni-Cu interface was indicated, by the presence of second-order satellite peaks around the main multilayer peak. The changes of crystallographic orientation as a function of the total thickness of the deposit demonstrate also the influence of the preferential crystallographic orientation of the multilayers on the size and nature of the magnetoresistance effect. The giant magnetoresistance effect (GMR) was dominant in samples with strong (111) texture and the anisotropy magnetoresistance (AMR) effect was observed in sampIes without any preferential crystallographic orientation.