APL007-2-2 Nickel Ferrite Nanostructures Prepared by DC Reactive Magnetron Sputtering

Abstract

In this work, a magnetic sensor was fabricated from nickel ferrite (NiFe₂O₄) nanostructures prepared by closed-field unbalanced dc reactive magnetron sputtering technique at low pressures. The nickel and iron targets were arranged to serve the quantitative aspect of the reaction forming nickel ferrite molecules before deposited on the substrate. Optimum samples were prepared using Ar:O₂ gas mixture of 30:70 mixing ratio, total gas pressure of 0.8mbar, discharge voltage of 1.8kV, discharge current of 25mA and inter-electrode distance of 4cm. These samples showed high structural purity as no peaks belonging to other compounds were observed in the x-ray diffraction patterns. The minimum particle size was determined to be 25nm. The average surface roughness of these samples was 0.465nm. The sensor devices fabricated from these samples were characterized to determine the optimum preparation conditions and the minimum magnetic field intensity detected by the fabricated sensor was 38.2G. The main features of the fabricated sensors are high reliability, low production cost and mechanical rigidity.