Effect of Oxygen Bombardment on Structural and Magnetic Properties of Ion-beam Deposited NiFe/Fe-oxide Bilayers

In this paper, the potential for new device materials and insight into the effects of some of the different iron oxide forms on exchange bias with NiFe (Permalloy) was discussed. The iron-oxides have significantly different magnetic properties. Thin film bilayers were deposited using a dual ion-beam deposition technique that produced an antiferromagnetic iron-oxide layer composition that ranged from Fe 3 O 4 to Fe 2 O 3 . The crystal structures of the Fe-oxide films were characterized by X-ray diffractometry (XRD). A JEOL (JEM-2010) Transmission electron microscope (TEM) operating at 200 kV was used for microstructural analysis. The magnetic properties such as exchange coupling and magnetic hysteresis of these bilayers were characterized using a vibrating sample magnetometer (VSM) and a superconducting quantum interference device (SQUID) magnetometry.