Magnetic, microstructural, and compositional characterization of Fe–N thin films for recording sensor applications

Abstract

The dependence of microstructural characteristics and magnetic properties on the processing conditions of reactively dc magnetron sputter-deposited Fe–N films (≤1000 Å) was investigated for advanced recording sensor applications. The N content of the film increases linearly as the ratio of N2 to Ar flow rate increases. Magnetic properties could be significantly modified by the incorporation of N into the Fe matrix. A N-content range was discovered where desirable soft magnetic properties such as low coercivity and low magnetostriction could be achieved. The soft magnetic properties originated from the amorphous microstructure as evidenced by transmission electron microscopy and x-ray diffraction. The electrical resistivity of Fe–N films with soft magnetic properties was an order of magnitude higher than that of pure Fe or NiFe thin films with comparable thickness.