Better carrier confinement in 0.6-&mgr;m-band laser diodes can be achieved by incorporating an AlInP layer into the (Al0.7Ga0.3)0.5In0.5P cladding layers. The effectiveness of this heterostructure, though, cannot be analyzed without detailed knowledge of the energy band alignment at theXc, &Ggr;c, and &Ggr;vband extrema. We conducted photoluminescence and photoreflectance measurements at 12–100 K on (Al0.7Ga0.3)0.5In0.5P/AlxIn1−xP heterostructures (x=0.47–0.61) free from long-range ordering, and analyzed the results to obtain basic data on the alignment scheme. In these measurements we observed the &Ggr;cto &Ggr;vand theXcto &Ggr;vtransitions in bulk Al0.53In0.47P and (Al0.7Ga0.3)0.5In0.5P alloys, the AlxIn1−xPXcto (Al0.7Ga0.3)0.5In0.5P &Ggr;vtransition in (Al0.7Ga0.3)0.5In0.5P/AlxIn1−xP superlattices, and theXcto &Ggr;vand to the &Ggr;cto &Ggr;vtransitions in 20-nm-wide AlxIn1−xP layers in (AlyGa1−y)0.5In0.5P/AlxIn1−xP/(AlyGa1−y)0.5In0.5P double heterostructures (x=0.33–0.39,y=0.7–1.0). We found that the energy level ofXcin AlxIn1−xP decreased by 0.09 eV asxincreased from 0.47 to 0.61, theXcof AlxIn1−xP crossed the &Ggr;cat 0.340 (±0.008), and the &Ggr;vof AlxIn1−xP crossed the &Ggr;vof (Al0.7Ga0.3)0.5In0.5P atx=0.47(±0.01). The share of the band offset at &Ggr;cforx=0.53 was 75(±3)&percent;. ©1997 American Institute of Physics.