MAGNETIZATION IN NI AND NI-FE THIN FILMS

Nickel films have been deposited in conventional high vacuum, ultra-high vacuum, and in controlled contaminant, ultrahigh vacuum environments. High field saturation magnetization Ms measurements on the films made in high vacuum and an oxygen-contaminated ultra-high vacuum system show that they posses low values of Ms for film thicknesses of 1000 A. The normal moments observed for ultra-high vacuum deposited films lead to the conclusion that the low Ms values are associated with the oxygen and are caused by a true loss of effective magnetization rather than coupled superparamagnetism or a ripple blocking field. Supplementary torque and ferromagnetic resonance studies on the Ni and two different Ni–Fe compositions also show that the grain boundary perpendicular anisotropy models are not particularly relevant for films made under such nominal technical vacuum conditions. © 1969, IEEE. All rights reserved.