Magnetic Properties of Iron Nitride Thin Films with High Corrosion Resistance

An ion and vapor deposition (IVD), method was used to fabricate iron nitride films for use as evaporated tape media, and their film properties evaluated. In the IVD process, iron was evaporated onto a substrate that was simultaneously bombarded by nitrogen ions. The ion current density J_ion was varied to investigate its effect on the deposited film. Increasing J_ion led to formation of ε-Fe₂~₃N over α-Fe, and to lower saturation magnetization and higher coercivity and squareness ratio. Iron nitride film samples showed no changes either in appearance or in magnetic properties even after exposure to a 5 percent saline solution for 300 h.