In situ and ex situ investigation of ion-beam-induced amorphization in α-SiC

Single crystals of α-SiC with [0001] orientation have been irradiated at 300 K with 360 keV Ar ²⁺ ions at an incident angle of 25°. The damage accumulation in one sample was followed in situ by Rutherford backscattering spectroscopy in channeling geometry (RBS/C) along the [1 overline102] direction until the aligned backscattering yield reached the random level throughout the irradiated layer at a fluence of 8 Ar ²⁺ ions/nm ². Six other samples were irradiated at fluences ranging from 1 to 6 Ar ²⁺ ions/nm ², and the damage accumulation was characterized ex situ by RBS/C along the [0001] direction. The relative disorder, as measured by RBS/C, increased with ion fluence; however, the observed rate of disordering was much lower when measured ex situ along the [0001] direction.