Authors: W.J. Fan, W.K. Cheah, S.F. Yoon, D.H. Zhang, R. Liu and A.T.S. Wee
Affilation: Nanyang Technological University, Singapore
Pages: 186 - 189
Keywords: GaAsN, MBE, PL, SIMS
Low-temperature (10K) photoluminescence (PL) measurements of GaAs1-xNx epitaxial layers grown on GaAs by solid-source molecular beam epitaxy (SSMBE) reveal an anomalous second peak. Rapid thermal annealing (RTA) of a specific GaAsN sample reveals a lower energy peak (γ) which redshifts and a higher energy peak (α) which blueshifts when increasing annealing temperature. The band anticrossing model is used to identify the origins of the two peaks and we propose a model to explain the RTA observations by the concept of increased confinement in areas of higher N concentrations by trapped N localized states. The γ peak is due to the accumulation of N content near the GaAs/GaAsN interface.