Magnetic and electronic structures of N Implanted Iron Oxide Thin Films

Abstract The present study investigates the effect of 26 keV N ions implantation on Iron oxide (Fe3O4) thin films of 100 nm deposited on Si (1 0 0) substrate by electron beam evaporation method. For this N ions implantation, an optimized ion fluence of 1 × 1016 ions/cm2 was used. The cubic spinel phase of Fe3O4 is confirmed by the Raman Spectroscopy. The magnetic properties and electronic structures of pristine and N ions implanted films were probed by using the Vibrating Sample Magnetometer (VSM), X-Ray Absorption Spectroscopy (XAS), and X-ray Magnetic Circular Dichroism (XMCD) at room temperature. The as-deposited film exhibits a reduced saturation magnetization due to the presence of a high density of defects such as amorphous boundaries and Fe vacancies which lead to the non-stoichiometric Fe3-δO4. The magnetic parameters Hc, Mr and MS determined from the hysteresis show enhancements after N ions implantation. This enhancement in the magnetic properties of N ions implanted Fe3O4 thin film is attributed to the healing of Fe vacancies and stoichiometric Fe3O4. Apart from this, an increment in the carrier concentration and reduction in resistivity is observed in the Hall effect measurements.