OPTICAL-PROPERTIES OF LOW-BAND-GAP GAAS(1-X)N-X LAYERS - INFLUENCE OFPOSTGROWTH TREATMENTS

A detailed study on the optical quality of atmospheric pressure metalo rganic vapor phase epitaxy grown GaAs(1-x)N-x epilayers (on GaAs subst rates) in which the N incorporation is accomplished using dimethylhydr azine precursor is reported. We show here that the poor optical qualit y of these as-grown layers can be significantly improved by carefully planned post-growth heat treatments. Optical data are presented to dem onstrate unambiguously that such treatments affect in no way the physi cal properties of these metastable layers (no phase separation) and th at the improvement of their optical quality is closely connected to th e incorporation behavior of N in this growth method. (C) 1998 American Institute of Physics.