Surface and interface modification of Zr/SiC interface by swift heavy ion irradiation

In this study thin Zr films (135 nm) were deposited on 6H-SiC substrate at room temperature by sputter deposition. The Zr/SiC couples were irradiated by 167 MeV Xe26+ ions at room temperature at fluences of 5.0 × 1012, 1.0 × 1013, 5.0 × 1013, 2.0 × 1014, 3.1 × 1014 and 6.3 × 1014 ions/cm2. The samples were analysed before and after irradiation using Rutherford backscattering spectroscopy (RBS), atomic force microscopy (AFM) and secondary electron microscopy (SEM). The surface morphology from SEM analysis revealed a homogeneous Zr surface which did not vary with increasing fluences of irradiation. AFM analysis revealed that the Rrms surface roughness did increase from the as-deposited value of 1.6 nm and then decrease at higher SHI irradiation fluences to 1.4 nm. RBS results indicate that interface mixing between Zr and SiC interface occurred and varied linearly with irradiation ion fluence. The value obtained for diffusivity of Zr shows that the mixing was due to interdiffusion across the interface during a transient melt phase according to the thermal spike model.