Room Temperature Ferromagnetism in Fe-Doped SnS Thin Films

Tin sulfide (SnS) has recently attracted significant attention as a multifunctional material due to its semiconducting, ferroelectric, and ferroelastic characteristics. In this work, we report the successful synthesis of Fe-doped SnS thin films using chemical vapor deposition (CVD) and investigate their structural, vibrational, and magnetic properties. Pristine SnS crystallized in the orthorhombic Pnma phase, exhibiting a direct bandgap of approximately 1.3 eV and an indirect bandgap of 1.1 eV. Incorporation of Fe into the SnS lattice induced noticeable structural and vibrational modifications, confirmed through X-ray diffraction (XRD) and Raman spectroscopy analyses. XRD patterns revealed a systematic shift and broadening of the (040) diffraction peak with increasing Fe concentration, indicating lattice strain and defect formation. Raman studies showed distinct shifts in both Ag and Bg vibrational modes, signifying dopant induced perturbations in the lattice dynamics. Energy dispersive X-ray spectroscopy (EDS) confirmed homogeneous Fe incorporation within the SnS matrix. Magnetic characterization using a Physical Property Measurement System (PPMS) revealed the emergence of ferromagnetism in Fe-doped SnS, absent in pristine samples. The saturation magnetization and coercive field increased with higher Fe concentrations, with pronounced anisotropy between in-plane and out-of-plane measurements. Moreover, temperature-dependent magnetization studies demonstrated that ferromagnetic ordering persists up to room temperature, highlighting the potential of Fe-doped SnS as a 2D magnetic semiconductor. These findings provide valuable insights into tailoring magnetism in SnS through transition metal doping, paving the way for its application in spintronic and multifunctional quantum devices.