SiC nano-dot formation in bulk-Si substrate using hot-C + -ion implantation process

We experimentally studied SiC nano-dot formation in a bulk-Si substrate fabricated by the very simple processes of a hot-C+-ion implantation into (100) bulk-Si substrate and the following N2-annealing, and the photoluminescence (PL) properties for a future Si-based photonic device. We confirmed by a transmission electron microscope that cubic and hexagonal SiC dots are formed in a C+-ion implanted Si layer, and the SiC dot diameter (3–7 nm) and density (1–2 × 1012 cm−2) depend on the process conditions. We also observed very strong PL-intensity after N2-annealing, and the broad PL spectrum can be fitted by the sum of the PL-emissions from four different cubic and hexagonal SiC-polytypes with different exciton bandgaps. The PL-properties strongly depend on the N2-annealing temperature, and hot-C+-ion implantation temperature and dose. Consequently, we successfully optimize the process conditions to improve PL-intensity, as well as to control the PL-spectrum line shape in the near-UV/visible regions.