Effects of Substrate Temperature on the Magnetic Properties of As-Sputtered FeTaN Films

We investigated the magnetic properties of as-sputtered FeTaN films as a function of deposition temperature and composition. At the deposition temperature higher than 200 [degrees] C, both soft magnetism and magnetic moments can be fully achieved. While the Ta and N contents in the films affect the magnetic properties, the N content exhibits stronger effects. The magnetic properties are affected by the film microstructures via. crystallinity, grain size, and formation of [Fe.sub.x]N phases. An excessive N incorporation into the films causes incomplete crystallization and/or formation of [Fe.sub.3] N phases in the as-deposited state, leading to a poor soft magnetic property. As-deposited FeTaN film at the optimum composition of [Fe.sub.91.7][Ta.sub.4.2][N.sub.4.1] gives the best soft magnetic properties; coercivity of ~2 Oe and permeability of ~1600 stable up to the frequency of 100 MHz. Index Terms--FeTaN, soft magnetism, substrate heating.