H2and N2contaminated amorphous CoGd and FeGd films

O
2
contamination of thermally evaporated CoGd and FeGd was investigated earlier and a model which explains the origin of the observed magnetic behaviour of the rare earth transition metal films was presented. This model, based on the formation of nonmagnetic inclusions in the magnetic material, should not only be applicable to O
2
contaminated films which hold non-magnetic oxide inclusions, but also to films with any nonmagnetic inclusions. We, therefore, investigated the magnetic properties of H
2
and N
2
contaminated CoGd and FeGd films. We found that N
2
and H
2
contamination has qualitatively the same influence on the magnetic behaviour as O
2
, which strongly supports the proposed model. To obtain perpendicular anisotropy in CoGd films a critical amount of about 10
^at
/o Gd has to be magnetically deactivated by the influence of the contaminating gases; these perpendicular anisotropic films exhibit a common minimum electrical resistivity of 2.6 × 10
^-4
Ω cm. H
2
and N
2
contamination yields also similar dependencies of the magnetic properties as found for O
2
contamination, however, to achieve the same effects the N
2
and H
2
pressures have to be considerably larger than the O
2
pressure.