Abstract
The previously reported photoluminescence(PL)-peak-energy anomaly problem for Ga0.5In0.5P grown on GaAs by metalorganic vapor phase epitaxy (MOVPE) was studied in detail. X-ray microprobe analysis, and optical transmission spectra measurements were carried out to examine alloy compositions and band-gap energies (Egs), respectively. The MOVPE growth condition dependence of {1/2, 1/2, 1/2} superlattices (SLs) on the cation sublattice in Ga0.5In0.5P was studied in detail, using transmission electron microscopy. The correlation between the Eg anomaly and the SLs was examined in detail and established. Raman spectra seemed to show zone-folding effects due to the monolayer SL. A similar Eg anomaly was reported for AlGaInP. AlGaInP and AlInP were also found to show the same SLs.