Hard magnetic thin films with high coercivity were fabricated by magnetron sputtering on MgO(100) and quartz substrates. The films were grown by depositing sequentially Sm and Co layers at an elevated substrate temperature of 500 °C. Subsequent post-annealing was carried out at various temperatures in range of 500–700°C to form Sm-Co hard magnetic thin films. X-ray diffraction studies revealed the formation of randomly oriented SmCo₅ crystallites on quartz substrate, whereas, a textured growth of Sm₂Co₇ with strong (110) crystalline phases was observed on MgO substrate. Microstructural analyses were carried out using Transmission Electron Microscopy (TEM) for samples grown on MgO substrate at 650°C and inferred the presence of high density planar defects along with large grain boundaries. Further microdiffraction studies