Effect of substrate temperature and bias voltage on DC magnetron sputtered Fe–N thin films

Abstract

Iron nitride films were deposited by DC magnetron sputtering using an Ar/N2 gas mixture at various substrate temperatures and substrate bias voltages. Using X-ray photoelectron spectroscopy (XPS), the composition of the films was analyzed. The structure, roughness, surface morphology, and magnetization of the films were investigated using X-ray diffraction (XRD), grazing incidence X-ray scattering (GIXS), atomic force microscopy (AFM), and superconducting quantum interference device (SQUIDS). Attempts have been made to correlate the phase structure, roughness, morphology and magnetization with the substrate bias voltage and substrate temperature. It was found that films deposited at different substrate temperature exhibited different structure, growth mechanism and magnetization. With the increase of the substrate temperature, the coercivity of the films has the tendency to increase. Except for roughness and coercivity of the iron nitride thin films, substrate bias voltage had little influence on the structure and saturation magnetization of the films. Films deposited at different substrate bias voltage will exhibit different coercivity. With the increase of substrate bias voltage, the coercivity of Fe-N films decreased.