Effect of N Addition into Fe-Hf-O Thin Films on Soft Magnetic Properties

Abstract

The effects of N addition into Fe-Hf-O sputtered films on magnetic properties and structure were investigated. The addition of N to Fe_93∼88Hf_2∼3O_5∼9 thin films was found ta decrease the coercivities (H_c) both at as-deposited state and after annealing at 773 K∼873 K because of decreasing grain size of α-Fe (bee phase). In particular, Fe_85.1Hf_2.1O_5.5N_7.3 films composed of phase with fine grain of about 150Å, γ'Fe₄N and Hafnium Oxide Nitride, exhibited low coercivity of 64 A/m and high saturation magnetization (B_s) of about 1.7 T even after annealing at 873 K. Thus, this thin film with high B_s. low H_c and high thermal stability is expected to be used as magnetic head materials.