Ion implantation in β-SiC: Effect of channeling direction and critical energy for amorphization

Damage in single-crystal β-SiC(100) as a result of ion bombardment has been studied using Rutherford backscattering/channeling and cross-section transmission electron microscopy. Samples were implanted with Al (130 keV) and Si (87 keV) with doses between 4 and 20 x 1014 cm-2 at liquid nitrogen and room temperatures. Backscattering spectra for He+ channeling as a function of implantation dose were initially obtained in the [110] direction to determine damage accumulation. However, the backscattered yield along this direction was shown to be enhanced as a result of uniaxial implantation-induced strain along [100]. Spectra obtained by channeling along this latter direction were used along with the computer program trIm to calculate the critical energy for amorphization. The results for amorphization of β-SiC at liquid nitrogen and room temperature are ∼14.5 eV/atom and ∼22.5 eV/atom, respectively