Time-resolved photoluminescence and capacitance–voltage analysis of the neutral vacancy defect in silicon implanted SiO2 on silicon substrate

Abstract

The nanosecond photoluminescence (PL) dynamics of neutral oxygen vacancy (NOV) defects at 410–460nm, and less pronounced nanocrystallite Si precursor (E′δ) defects at 520nm in multi-energy silicon-ion-implanted SiO2 (SiO2:Si+) are investigated. The density of NOV defects in as-implanted SiO2:Si+ of 8×1016cm−3 (or 2.5×1016cm−3 calculated from time-resolved PL) is determined by using capacitance-voltage measurement. After annealing at 1100°C for 3h, the NOV defects are completely activated with a concentration of 4.8×1017cm−3 and a corresponding absorption cross section of 9×10−17cm2. The time-resolved PL lifetime of NOV defects in SiO2:Si+ is significantly shortened from 26to3.6ns and these defects are fully activated after annealing for 3h. Longer annealing time greatly attenuates the blue-green PL intensity and eliminates the NOV defects, whereas the PL intensity and concentration of E′δ defects with lifetime of 20–50ns increases by a factor of 2.