Структурные и оптические свойства оксида кремния, имплантированного ионами цинка: влияние степени пересыщения и термообработки

Abstract

The phase-structural composition of a silica film grown on Si substrate implanted with Zn ions at room temperature with different fluences has been studied using transmission electron microscopy and electron diffraction. The small clusters (1–2 nm) and the large clusters (5–7 nm) have been formed in as-implanted silica films with the Zn concentration of 6–7 at % and 16–18 at %, respectively. Furnace annealing at 750 °С for two hours results both in the formation of the orthorhombic Zn 2 SiO 4 phase (space group R-3) in the case of low fluence (5 · 10 16 cm –2 ) and in the formation of the cubic ZnO phase (space group F-43m) in the case of high fluence (1 · 10 17 cm –2 ). It has been shown that impurity loss during implantation and subsequent annealing increase with fluence of implanted ions. The fraction of Zn atoms in clusters has been estimated to be 15 % and 18 % for fluences (5 · 10 16 cm –2 ) and (1 · 10 17 cm –2 ), respectively. It has been shown that residual Zn impurities dissolved in silica matrix noticeably suppress the light-emitting properties of silica with embedded Zn 2 SiO 4 and ZnO nanocrystals.