INFLUENCE OF THE GROWTH TEMPERATURE AND SUBSTRATE ORIENTATION ON THE LAYER PROPERTIES OF MOVPE-GROWN (GA,IN)(AS,P) GAAS/

The luminescence properties of In1-xGaxAsyP1-y layers and heterostruct ures grown lattice matched to GaAs by metalorganic vapour-phase epitax y (MOVPE) were studied and correlated to the crystalline properties. F or laser structures emitting around 800 nm a red-shift of the emission from the active layer (y = 0.72) grown at 680 degrees C together with an anomalous temperature behaviour and excitation dependence of the b andgap is observed. Although some degree of ordering is observed for t hick layers of this composition, polarization dependent photoluminesce nce does not indicate ordering of the quantum well to be the main reas on for this excitation dependence. Instead, interfacial In-rich layers are found to be responsible. The thickness of these interfacial layer s strongly depends on substrate misorientation and growth conditions.