We experimentally studied the optimization of the hot-C + -ion implantation process for forming nano-SiC (silicon carbide) regions in a (100) Si-oninsulator substrate at various hot-C + -ion implantation temperatures and C + ion doses to improve photoluminescence (PL) intensity for future Sibased photonic devices. We successfully optimized the process by hot-C + -ion implantation at a temperature of about 700 °C and a C + ion dose of approximately 4 ' 10 16 cm %2 to realize a high intensity of PL emitted from an approximately 1.5-nm-thick C atom segregation layer near the surface-oxide/Si interface. Moreover, atom probe tomography showed that implanted C atoms cluster in the Si layer and near the oxide/Si interface; thus, the C content locally condenses even in the C atom segregation layer, which leads to SiC formation. Corrector-spherical aberration transmission electron microscopy also showed that both 4H-SiC and 3C-SiC nanoareas near both the surface-oxide/Si and buried-oxide/Si interfaces partially grow into the oxide layer, and the observed PL photons are mainly emitted from the surface SiC nano areas.

We experimentally studied SiC nanodot formation in an amorphous-Si (a-Si) and poly-Si on quartz substrates, using a hot-C+-ion implantation technique and post-N2 annealing, compared with SiC-dots in a (100) crystal-Si (c-Si) on insulator substrate. Even in the poor crystal quality substrates of the C+-ion implanted in a-Si and poly-Si layers, we experimentally verified 3C-SiC dot formation by transmission electron microscopy, and the strong photoluminescence (PL) intensity in the near-UV-vis regions, because a-Si is partially poly-crystallized by the high-temperature processes of hot-C+-ion implantation and post-N2 annealing. The PL spectral line shape strongly depends on the Si crystal structures, but the peak PL intensity after N2 annealing is almost independent of the Si crystal structures. Moreover, the PL spectrum can be explained by the sum of PL emissions from different cubic and hexagonal polytypes of SiC. We clarified that the three Si crystal structures have a different contribution ratio of PL components of SiC polytypes.

We experimentally studied the material structure and photoluminescence (PL) properties of SiC quantum-dots (QD) in SiO 2 layer (Si + /C + -OX) fabricated by double hot-Si + /C + ion implantation into SiO 2 and the post N 2 annealing, comparing with those of SiC-dots by single hot-C + ion implanted oxide (C + -OX) and crystal-Si layers (C + -Si). X-ray photoemission spectroscopy for Si + /C + -OX confirmed Si-C bonds even in SiO 2 , which is the direct verification of SiC formation in SiO 2 . Moreover, transmission electron microscope analyzes showed that 2 nm diameter SiC-dots with a clear lattice spots were successfully formed in Si + /C + -OX. After N 2 annealing, we demonstrated strong PL emission from Si + /C + -OX, and the PL intensity I PL of Si + /C + -OX is approximately 2.6 and 12 times larger than those of C + -Si and C + -OX, respectively. The stronger I PL of Si + /C + -OX is possibly attributable to QD-induced PL-efficiency enhancement in Si + /C + -OX. Moreover, PL photon energy at the peak I PL of Si + /C + -OX rapidly increases to approximately 2.4 eV after N 2 annealing.

We experimentally studied three types of group-IV-semiconductor quantum-dots (IV-QDs) of Si-, SiC-, and C-QDs in a thermal SiO2 layer that were fabricated using a very simple hot-ion implantation technique for Si+, double Si+/C+, and C+ into the SiO2 layer, respectively, to realize a different wavelength photoluminescence (PL) emission from near-IR to near-UV ranges. TEM analyses newly confirmed both Si- and C-QDs with a diameter of approximately 2–4 nm in addition to SiC-QDs in SiO2. We successfully demonstrated very strong PL emission from three IV-QDs, and the peak photon energies (E PH) (peak PL-wavelength) of Si-, and SiC-, and C-QDs were approximately 1.56 eV (800 nm), 2.5 eV (500 nm), and 3.3 eV (380 nm), respectively. IV-QDs showed that the PL properties strongly depend on the hot-ion doses of Si and C atoms and the post N2 annealing processes. Consequently, it is easy to design peak PL wavelengths by controlling the ion doses of Si+ and C+ implanted into the SiO2 layer.