Kinetic of recombination processes involving defect-related states in as-grown Si-doped GaAsN/GaAs epilayer

Abstract

In this paper, recombination dynamics in GaAs1-xNx semiconductor alloy with a nitrogen content of 1.6% are investigated using Photoluminescence (PL) and Time-Resolved Photoluminescence (TRPL) Spectroscopy. At temperature below 80K, the TRPL measurements show the competition of two recombination processes with two different decay times. The localized to delocalized electron transition with slow decay time and the non-radiative trapping processes with shorter decay time. At higher sample temperatures, the non-radiative trapping processes dominate the transition and lead to mono-exponential decay behavior with shorter PL decay time. Moreover, the PL decay exhibits a strong energy dispersion. The dependence of PL decay time on emission energy was explained by the contribution of the N-related states in the radiative recombination processes.