Electronic stopping cross sections in silicon carbide for low-velocity ions with 1⩽Z1⩽15

Abstract

The mean projected range Rp for a large number of H1, H2, Li7, B11, N14, O16, Al27, and P31 implantations into SiC with ion energies ranging from 0.5 keV to 4 MeV are investigated. From the Rp data the electronic stopping cross sections Se are extracted. A plot of the extracted Se at a fixed velocity—below the Fermi velocity of the target valence electrons—versus the ion atomic number Z1 reveals a local maximum around Z1=7. Furthermore, in this velocity regime a slower than velocity-proportional energy dependence, Se∝E0.30–E0.45, is found for ions with 1⩽Z1⩽8, while Al27 and P31 exhibit an energy dependence just above velocity-proportionality: Se∝E0.52, for both ions. These finding are in good qualitative agreement with the low-velocity electronic stopping behavior previously reported for carbon targets.