Silicon nanocrystals have been synthesized in SiO2 matrix using Si ion implantation. Si ions were implanted into 300-nm-thick SiO2 films grown on crystalline Si at energies of 30-55 keV, and with doses of 5 × 1015, 3 × 1016, and 1 × 1017 cm-2. Implanted samples were subsequently annealed in an N2 ambient at 500-1100°C during various periods. Photoluminescence spectra for the sample implanted with 1 × 1017 cm-2 at 55 keV show that red luminescence (750 nm) related to Si-nanocrystals clearly increases with annealing temperature and time in intensity, and that weak orange luminescence (600 nm) is observed after annealing at low temperatures of 500°C and 800°C. The luminescence around 600 nm becomes very intense when a thin SiO2 sample is implanted at a substrate temperature of 400°C with an energy of 30keV and a low dose of 5 × 1015 cm-2. It vanishes after annealing at 800°C for 30 min. We conclude that this luminescence observed around 600 nm is caused by some radiative defects formed in Si-implanted SiO2.
Bibliographical noteFunding Information:
This work was supported by the Korea Science and Engineering Foundation (KOSEF) through the ASSRC at Yonsei University, in part by the basic research fund of KIST (2E15540), and in part by grants from KOSEF (981-0209-035-2).
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics