Fe-N gradient thin films are fabricated by a facing targets sputtering (F-f S) system. Rutherford backscattering spectrometry shows that the concentration of Fe atoms or N atoms varies gradually from the substrate to the surface of the film. The Fe-N gradient films contain crystal phases of ζ-Fe2N, ε-FexN (2<x<3), γ'-Fe4N and α"-Fe16N2, and amorphous FeN as well, according to different sputtering conditions.

The perpendicular magnetic properties of NdFe alloy thin films have been studied on samples prepared by the facing targets sputtering method at a substrate temperature of 240-270 C. All the films with Nd content over 35 at.% exhibit perpendicular magnetic anisotropy. The Curie and crystalline temperatures were about 400 K and 630 K, respectively. The x-ray diffraction patterns show that the uniaxial anisotropy of a NdFe film has a certain relation to the partial oxidation of Nd in the film. The direction of the magnetic easy axis is determined by the orientation of C-Nd203; (440)-oriented C-Nd203 contributes to the formation of a perpendicular magnetic film. It is proposed that the partial oxidation of Nd may induce some short range atomic order in NdFe films.

The magnetic and magneto optic (MO) properties of facing Targets Sputtered (FTS) Dyx Nds(Fe75Co25)95-x amorphous films were investigated When x is over 12 at%, the easy magnetizalion axis is perpendicular to the film plane The effets of various preparation conditions were also examined, both 470K substrate temperature and 110 V bias can enhance the nniaxial aniaotropy of the films; substrate bias causes M, to decrease and Hc to increase, substrate heating will have the opposite effects These interesting results show that DyNdFeCo this films have properties similar to both Dy TM and Nd-TM thin films Furthermore, it is shown that Ihe Nd componem has a similar conmbution to the uniaxial anisotropy as the Dy component in DyNdFeCo thin films.

Fe-N films with 20nm thick Fe underlayers were deposited on Si(100) substrates by RF magnetron sputtering, and their structure and magnetic properties were investigated. It was found that the optimum nitrogen partial pressure for α phase formation is about 2×10−4 Torr, and the saturation magnetization measured at room temperature of the Fe-N films deposited at this pressure is as high as 2179emu cc−1, which is much higher than that of pure iron. Film thickness dependence of the saturation magnetization shows that it initially increases with the increase in film thickness and reaches a maximum of～2179emu cc−1 in the thickness range of 300-570nm, and decreases with a further increase in film thickness.

The Fe nitride fiims were easily produced by facing targets sputtering (FTS). The structures and magnetic properties of the films depend on the reactive pressure (PN) and dc substrate biasing voltage (Vb)o α-Fe, α"-Fe16N2, γ-Fe4N, ε-Fe3N, and ζ-FezN as well as the amorphous FeN phase have been produced at the PN ranges of 0-8～10-3 Torr. The magnetic moment per iron atom increases with PN until PN=1.O mTorr at which the α'-Fe16N2 phase appears with the coercive force Hc=103A/m, susceptibility γ=161, and μs=2.85 μB. The relation between conductivty and temperature σ-T indicates that Fe nitride films resemble a semiconductor. The Curie temperature of these films is reduced with the increase of PN. Magnetic relaxation phenomena were observed in the vicinity of 540℃.