Bonding of nitrogen in dilute GaInAsN and AlGaAsN studied by Raman spectroscopy

摘要

To gain information on the local bonding of the nitrogen, Ga_(1-x)In_xAs_(1-y)N_y, with x≤0.12 and y≤0.04 and Al_xGa_(1-x)As_(1-y)N_y with x ≤ 0.05 and y ≤ 0.04 have been studied by Raman spectroscopy. When adding In to GaAsN, the nitrogen-induced vibrational mode near 470 cm~(-1) observed in GaAsN was found to split into up to three components, with one of the In-N related modes at higher and the other at lower frequencies than the Ga-N mode. Upon thermal annealing, the relative mode intensities were found to change in favor of the In-N related modes, indicating a redistribution of the Ⅲ-N bonds. For Al_xGa_(1-x)As_(0.99)N_(0.01), in contrast, the almost exclusive formation of complexes with Al-to-N bonding was observed already for a low Al content of x = 0.05, as seen from a complete switch in mode intensity from the Ga-N mode at 470 cm~(-1) to a new Al-N related mode near 450 cm~(-1). This result was confirmed by a corresponding analysis of the quinary compound AlGaInAsN.