Pulsed electrodeposition of nanocrystalline CoNiFe soft magnetic thin films

A pulsed electrodeposition method was applied to the preparation of soft ma gnetic CoNiFe films in the compositional region corresponding to the phase boundary between face-centered cubic (fcc) and body-centered cubic (bcc) st ructures. Crystalline grain size was found to be almost the same, smaller t han 10 nm, and independent of the duty cycle which is the ratio of the puls e-on time to the pulse-on plus pulse-off period. Depending on the operating conditions, the ratio of bcc to fee varied. Current efficiency decreased w ith decreasing duty cycle and pulse current density. The intensity ratio of bcc(110) to fcc(111) X-ray diffraction peaks showed a maximum at the opera ting conditions in which the transition from kinetic to mass-transfer contr olled deposition occurred with only a slight increase of Fe content (approx imately 1 atom %). Magnetic properties were suggested to be controllable by adjusting the bce-fcc ratio using pulsed electrodeposition. (C) 2001 The E lectrochemical Society.