Solid phase epitaxy of ultra-shallow Sn implanted Si observed using high-resolution Rutherford backscattering spectrometry

Abstract

We present detailed observations of the solid phase epitaxy process in Sn-implanted Si samples with nanometric depth resolution within a 50 nm ultra-shallow region beneath the surface. Measurements were made using high-resolution Rutherford backscattering spectrometry coupled with the ion channeling technique. Samples with Sn ions implanted onto Si substrates with and without prior Si+ self-amorphization implantation process show different crystal regrowth characteristics during annealing. Regrowth proceeds at a non-uniform rate up to a certain depth before stopping, and an Arrhenius-type defect density limiting model of crystal regrowth is proposed to account for this effect.