High frequency characteristics of As-sputtered Co-Ni-Fe-N soft magnetic thin films

Abstract

Co-Ni-Fe-N soft magnetic thin films with excellent high frequency characteristics were fabricated by a N-2 reactive A magnetron sputtering method. The nitrogen partial pressure (P-N2) was varied in the range of 0 similar to 10%. As P-N2 increases in this range, the saturation magnetization (B-s) linearly decreases from 19.8 kG to 14 kG and the electrical resistivity (rho) increased from 27 mu Omega cm to 155 mu Omega cm. The coercivity (H-c) exhibits the minimum value at 4% P-N2. The magnetic anisotropy field (H-k) are in the range of 20 similar to 40 Oe. High frequency characteristics Of (Co22.2Ni27.6Fe50.2)(100-x)N-x films are excellent in the range of 3 similar to 5% P-N2. Especially, the effective permeability of the film fabricated at 4% P-N2 is about 800, which is maintained up to 600 MHz. This film exhibits B-s, of 17.5 kG, H-c of 1.4 Oe, rho of 98 mu Omega cm, and H-k of about 25 Oe. The corrosion resistance of (Co22.2Ni27.6Fe50.2)(100-x)N-x. is improved with the increase of N concentration.