GROWTH OF HIGH-QUALITY INALP/INGAP QUANTUM-WELLS AND INALP/INGAP SUPERLATTICE BARRIER CLADDING LAYERS BY METALORGANIC CHEMICAL-VAPOR-DEPOSITION

In this paper, we present results of studies of high-quality InGaP quantum well (QW) heterostructures grown by metalorganic chemical vapor deposition (MOCVD). The QWs have been grown on GaAs:Si substrates having orientations of both (100) and (100)-10 degrees off toward the nearest [110]. We have employed both InAlP ternary alloy cladding layers and specially designed InAlP-InGaP superlattice barrier (SLB) cladding layers. The 4.2 K and 300 K photoluminescence (PL) emission from both the InGaP QW and the InAlP/InGaP SLB heterostructures exhibits very narrow line widths and high intensities, indicating that these structures have relatively smooth interfaces and that they are of high quality. While studies of InAlGaP injection lasers using similar SLBs have been published previously, to our knowledge, detailed photoluminescence studies of ternary/ternary SLBs in the InAlGaP system have not been reported. We have performed calculations of the performance of InAlP/InGaP ternary SLBs and these calculations show that an optimum QW heterobarrier can be achieved for an all-ternary SLB consisting of 10 pairs of InAlP (similar to 1.7 nm) and InGaP (similar to 0.9 nm) and an InAlP ''first barrier layer'' similar to 20 nm thick. Emissions from the InGaP wells grown on off-orientation substrates appear to have narrower linewidths and higher intensities in the InGaP/InAlP system as was previously demonstrated for the InGaP/InAlGaP system. PL data from the InGaP/InAlP short-period superlattices, to the best of our knowledge, are shown for the first time.