Tailoring of magnetic phase: Co-doped SiC thin films grown by RF sputtering

Abstract

In the present work, we investigate the influence of cobalt (Co) doping on the structural and magnetic properties of cobalt-doped silicon carbide (Co-SiC) thin films. The films were fabricated using DC/RF magnetron sputtering technique on Si (100) substrates at a temperature of 1200°C, with varying Co concentrations ranging from 5 to 16 at. (at%. X-ray diffraction (XRD) analysis unveiled the co-existence of CoSi₂ and SiC phases in all the thin films. Surface morphological study through atomic force microscopy (AFM) revealed the densely packed nature of the films. Field emission scanning electron microscopy (FE-SEM) study showed that particles are uniformly distributed at the surface of the substrate. According to UV measurements, the films have high transmittance in the visible range, and as Co concentration rises, transmittance decreases. A magnetic phase transition from superparamagnetic to ferromagnetic behavior occurred with Co content surpassing 8 at% in the SiC thin films. Moreover, an increase in coercivity was observed from 38 Oe to 316 Oe as the doping concentration increased from 10 to 16 at%. This study represents an exploration into the induction of ferromagnetism through moderate Co doping in SiC thin films.