Effect of deposition potential and saccharin addition on structural, magnetic and magnetoresistance characteristics of NiCoFeCu films

Abstract

NiCoFeCu films were electrodeposited on Ti substrates at different deposition potentials and different concentrations of saccharin added to solution. Compositional analysis showed that although Ni was the highest concentration in solution at low potentials of -1.0 V and -1.5 V, the Ni content was lower than the Co content in the films. Anomalous co-deposition behaviour of iron group metals was observed. When the deposition potential increased to -2.0 V and -2.5 V, the Ni content of films increased while the Co, Fe and Cu content decreased. In the case of saccharin addition to the solution, there is a slight change in the film content. All films have face-centred cubic structure. Structural analysis clearly showed that the potential has a significant effect on the texture degree of the films, since the crystal texture changed from (111) to (220) with increasing potential. The surface morphology of the films was observed to be affected by the deposition potential and saccharin concentration. For the magnetic analysis, saturation magnetisation, Ms value gradually decreased from 905 to 715 emu/cm3 with the variation of film content caused by the increase of the potential from -1.0 V to -2.5 V. And, a slight increase in Ms was detected with the addition of saccharin. Besides, the longitudinal and transverse magnetoresistance magnitudes increased from ∼2.5 % to 7.0 % with increasing deposition potential and all films exhibit anisotropic magnetoresistance. Films with desired magnetic properties can be obtained for potential use as magnetic materials in electronics such as magnetoresistive devices.