Photoluminescence dependence on heterointerface for metalorganic chemical vapor deposition grown GaInNAs/GaAs quantum wells

We investigate the effect of the sequence of gas flows at heterointerfaces on optical quality of GaInNAs/GaAs quantum wells grown by metalorganic chemical vapor deposition (MOCVD). We point out that the degradation mechanism of photoluminescence of GaInNAs grown by MOCVD method is categorized in two types. One is the formation of a GaNAs layer at the heterointerface which causes both increase of emission wavelength and degradation of crystal quality. The other is generation of nonradiative centers induced by incorporation of nitrogen (N). The insertion of a GaInAs layer to the GaInNAs/GaAs heterointerface is proposed to overcome these degradation mechanisms. A GaInAs intermediate layer is effective to suppress the GaNAs formation and to reduce the total GaInNAs thickness.