Nano-SiC region formation in (100) Si-on-insulator substrate: Optimization of hot-C⁺-ion implantation process to improve photoluminescence intensity

Abstract

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.

Thermally Robust High‐Resistance Layers on Low‐Resistance Silicon Synthesized by Molecular CO+ Ion Implantation

“…Similar reasons are responsible for the shape of the SIMS profile of the detected secondary SIN ions. The similarity of nitrogen distribution to the profile of 12 C atoms, with the exception of the SiO 2 /Si boundaries, indicates the coimplantation of N 2 þ ions with CO þ ions, as well as their coprecipitation with carbon atoms.…”

“…The C atoms escape from the silica layer and three SiC nucleation peaks at the center and a possible border position between the crystalline and amorphous Si layer, formed due to a high dose implantation inside the bulk silicon, also correlate with the data. [ 12,13 ] It is interesting to note that there is not a strong C and O atom correlation inside silicon. Similar reasons are responsible for the shape of the SIMS profile of the detected secondary SIN ions.…”

Physical mechanism for photon emissions from group-IV-semiconductor quantum-dots in quartz-glass and thermal-oxide layers

“…Recently, for realizing Si-based photonics, [1][2][3] we have been experimentally studied photon emissions from nano-structures of group-IV semiconductors (Si, SiC, and C), such as two-dimensional (2D) Si, 4,5) SiC-nano-dots in various crystal structures of Si [6][7][8][9][10][11] [amorphous-Si (a-Si), poly-Si, crystal-Si (c-Si)], and group-IV semiconductor quantum-dots (IV-QD) of Si, SiC, and C in thermal Si-oxide (OX). 12,13) Si-, SiC-, and C-dots were fabricated by very simple hot-ion implantations of single Si + , double Si + /C + , and single C + , respectively, and a post N 2 annealing was carried out to improve the dot quality.…”

“…On the other hand, the self-clustering effects of ionimplanted atoms in Si and OX, which was evaluated by atom probe tomography, 6,17,18) leads to the local condensation of implanted atoms with the Φ of several nm in Si and SiO 2 layers, resulting in the local formation of nano-dots in Si and QDs in OX. 6,12,13) As a result, vacancies 19) are formed in QDs and at the SiO 2 /QD interface, because of imperfect crystallization of QDs during hot-ion implantation process.…”

Core and Surface Electronic States and Phonon Modes in SiC Quantum Dots Studied by Optical Spectroscopy and Hybrid TDDFT

“…On the other hand, the sp 2 -carbon at the SiC surface can improve the specific contact resistance of the SiC/metal interface . The surface of SiC accommodates diverse surface reconstruction and termination with corresponding defects such as bridge and triple-bonded C/Si dimers, which generate fruitful surface states in the band gap. − Hence, the SiC surface has attracted great interest. , As the dimension of the semiconductor SiC is reduced to the nanoscale, its surface structure becomes even more complex, the dangling bonds of the active carbon and silicon atoms of the freshly prepared SiC quantum dots (QDs) can readily be passivated by oxygen and hydrogen atoms to form quite fruitful bonding structures. − The resultant surface states in the band gap can actively participate in the photon absorption and emission processes. − The whole surface passivation layer becomes a two-dimensional quantum system, which in combination with quantum confinement − and the intentionally created interior point defects − determines the photodynamics ,− and charge transport properties of the SiC QDs. Therefore, understanding the surface structures and characteristics of the SiC QDs is critical for realizing their better applications in biological labeling, − solid-state lighting, − and quantum spintronics. − Our previous study indicates that the CO bonds on the SiC QD surface generate surface-localized orbitals and contribute to the blue fluorescence; however, the role of the silicon–oxygen bonds in fluorescence of the SiC QDs remains unclear.…”