.. ELECTROCHEMICAL SYNTHESIS OF LAYERED NANO CRYSTALLINE' LAMINATES AND ITS CHARACTERISATION

Abstract

Electrochemical synthesis of layered nanocrystalline laminates were studied by adopting magnetic multilayer system as a model. Multilayers of cobalt and copper, which are known to exhibit giant magnetoresistance, were synthesized from a single sulphate-bath using potentiostatic mode, galvanostatic mode, potentiostatic/galvanostatic mode and a new technique pulsed current mode. The pulsed current mode in the deposition of multilayers was investigated as it is known to produce smoother deposits so that interfacial mixing of layers can be minimized. The multilayers were characterized using energy dispersive x-ray analysis, x-ray diffraction analysis, magnetoresistance measurements and atomic force microscopy analysis and the results were analyzed to compare the deposits synthesized under different modes. The results indicated that the galvanostatic deposition mode yields smoother surface finish and the roughness evolution in the pulsed current mode is due to the dissolution of cobalt during pulse off times.