Dynamic annealing study of SiC epilayers implanted with Ni ions at different temperatures
Résumé
SiC epilayers grown on 4H-SiC single crystals were implanted with 850 keV Ni(+) ions with fluences in the 0.5-9 x 1016 Ni(+)/cm(2) range. Most of the samples were implanted at 450 degrees C, but for comparison some implantations were performed at room temperature (RT). In addition, a post-implantation annealing was performed in N(2) at 1100 degrees C in order to recover from the implantation-induced structural damage. The disorder produced by the implantation at 450 degrees C and the effect of the post-implantation annealing on the recrystallization of the substrates have been studied as a function of the fluence by Backscattering Spectrometry in channeling geometry (BS/C) with a 3.45 MeV He(2+) beam. RT as-implanted samples showed a completely amorphous region which extends until the surface when irradiated with the highest dose, whereas in the case of 450 degrees C implantation amorphization does not occur. In general, partial recovery of the crystal lattice quality was found for the less damaged samples, and the dynamic recovery of the crystalline structure increases with the irradiation temperature. (c) 2009 Elsevier B.V. All rights reserved.