A. I. Krikunov

Magnetic anisotropy induced in the nanocrystalline FeZrN films prepared by oblique-angle magnetron sputtering

Nanocrystalline Fe77Zr7N16 films are prepared by oblique-angle magnetron sputtering. The effect of the ion beam angle and subsequent annealing on the phase and structural states, the coercive force, the saturation magnetization, the remanent magnetization, and the induced in-plane magnetic anisotropy field has been studied. The possibility of natural ferromagnetic resonance in these films at gigahertz frequencies is estimated.

Measurement of magnetic parameters of nanometer-thick conducting magnetic films using anisotropic magnetoresistive effect

The angular dependences of anisotropic magnetoresistance (AMR) are measured in conducting ferromagnetic films of nanometer thickness and layered structures containing such films and having the shape of narrow ribbons. These structures are used for preparing spin-dependent magnetic tunnel junctions possessing a giant magnetoresistance. The possibility of determining the main magnetic parameters, which are important for preparing magnetic junctions, by AMR angular measurements is demonstrated experimentally. The magnetic anisotropy axis, the saturating magnetic field, and the coercivity are determined in a 25-nm-thick permalloy (Py) film, in the structures FeMn film (15 nm)-Py film (10 nm) deposited by RF magnetron sputtering on a oxidized silicon substrate, as well as in the structure FeMn (15 nm)-Py (10 nm)-SiC (1.5 nm)-Py (10 nm) deposited on a sitall substrate. It is shown that, under the same conditions of Py films deposition, the magnetic anisotropy axis in the FeMn-Py structure is turned through 90° relative to the anisotropy axis of Py in structures without FeMn layers. The value of the exchange bias fields of the magnetization reversal measured in the structure FeMn (15 nm)-Py (10 nm)-SiC (1.5 nm)-Py (10 nm) by the AMR method is in good agreement with the result of measurement by the inductive method.

Use of the anisotropic magnetoresistance effect for direct measurement of the coercivity and exchange bias fields of magnetization reversal in conducting magnetic films of nanometer thickness

The anisotropic magnetoresistance effect has been used for direct measurement of the coercivity and exchange bias fields of magnetization reversal in conducting ferromagnetic films of nanometer thickness and in sandwich structures containing such films, which are used in spin dependent tunneling junctions featuring colossal magnetoresistance. The measurements have been performed for 25-nm-thick permalloy (Py) films obtained by RF magnetron sputtering on oxidized silicon substrates and for FeMn(15 nm)/Py(10 nm)/SiC(1.5 nm)/Py(10 nm) structures on glass ceramic substrates. The results of measurements performed using the proposed method are in satisfactory agreement with the data obtained by the induction method.

Thin-film magnetically soft Fe-Zr-N alloys with high saturation induction

Thin films of magnetically soft nanocrystalline alloys of the Fe-Zr-N system with a high (1.6–1.8 T) saturation induction and a very low (record) coercive force (4–6 A/m) were obtained by magnetron sputtering followed by thermal treatment of the deposit. Direct magnetooptical observation of the domain motion revealed a high homogeneity of the film material and showed that remagnetization in the material proceeds by mechanism of the domain boundary displacement.