CoFe and low phosphorus containing (<4 at.%) CoFeP alloy films were electrodeposited from NaH
2PO
2 containing solutions at pH 4 on copper substrates under galvanostatic conditions. At the low phosphorus composition, nanocrystalline
CoFeP alloy films are formed. The structure, composition and morphology of the thin films were studied using X-ray diffraction,
energy dispersive spectroscopy and atomic force microscopy. The magnetic properties of the film were studied using superconducting
quantum interference device magnetometer. The thin film performance features were explained on the basis of microstructural
features developed during deposition. Whereas the electrodeposited CoFe alloy thin film exhibited mixed hcp and fcc phase
structure in the absence of phosphorus, the low phosphorus containing thin film exhibited an increasing mixed bcc and hcp
phase structure as its phosphorus content increases, showing modification in the grain size morphology and magnetic properties.
In addition to applied current, the amount of P co-deposited in CoFeP alloy depends on the concentration of NaH
2PO
2 source in the bath. Qualitative analysis of the Tafel slope of CoFe and CoFeP deposition suggests that the presence of P
in the CoFe deposit does not affect the mechanism of anomalous deposition of Co and Fe, thereby suggesting that CoFeP deposition
is anomalous.
Keywords Electrodeposition - CoFeP - Magnetic - Alloys - Nanocrystalline - Coercivity - Anomalous - Co-deposition - CoFe