Structural and optical quality of InGaAsN quantum wells grown on misoriented GaAs (1 1 1)b substrates by molecular beam epitaxy

Abstract

An analysis of the effect of different growth parameters in the optical and structural properties of InGaAsN quantum wells (QWs) on misoriented (111)B GaAs substrates is presented. The nitrogen incorporation and crystal quality were found to be dependent on the arsenic flux used. The effect of the low temperature GaAs as cap layers for the QWs was studied by atomic force microscopy and by reflection high energy electron diffraction observations of the growing surface. New features in the (2×2) reconstruction were observed whilst growing at low temperature under a nitrogen atmosphere in the chamber, possibly due to competition between As and N species on the surface. This study has led to the fabrication of QW structures emitting at wavelengths above 1.5μm, the longest reported up to date for this kind of substrates.