Structural properties of AlGaP films on GaP grown by gas-source molecular-beam epitaxy

The growth of Al0.85Ga0.15P on GaP using gas-source molecular-beam epitaxy is investigated using in situ high-energy electron diffraction, high-resolution x-ray diffraction, atomic-force microscopy, and scanning electron microscopy. Growth temperature and phosphorus flux were varied. The 1.0-μm AlGaP films were grow on a GaP buffer layer and capped with GaP. The investigation indicates that a growth temperature of 490 °C and a cracked PH3 flux of 2.7 sccm resulted in the best AlGaP quality, while maintaining very good GaP quality.