Magnetic anisotropy in dc-diode getter sputtered GdCo films - How important is the argon content in the films?.

Amorphous magnetic GdCo films were prepared by a dc-diode getter sputtering technique with no bias field applied to the substrate during the film growth. Films (type l) obtained using 1.0 kV and 60 mTorr Ar during the sputtering show perpendicular anisotropy with K(eff)(sub u) = 1.5x10(5) erg/cm(3). Films (type ll) with 2.0kV and 28 mTorr Ar exhibit in-plane anisotropy with K(ln)(sub u) ~~ 0. However, the actual argon content in the type ll films is three times of that in the type l films. Nevertheless, the argon impurity in both the type l and type ll films is below 1.5 at .% which is far less than those obtained in the biased rf-diode sputtered GdCo films.