Applied Physics Letters · 1996 · 61 citations · 0 references
Natural SciencesMaterials SciencePhysicsCondensed Matter PhysicsElectronic MaterialsSemiconductor MaterialsChemical Vapor DepositionEpitaxial GrowthSemiconductor Crystal GrowthSemiconductor NanomaterialsWide Band Gap SemiconductorsWide-bandgap SemiconductorsBand GapBand Gap EnergyEnergy Band GapMetalorganic Chemical Vapor DepositionSuperlattice GrowthSuperlattice MaterialsSuperlatticesTemperature-dependent Growth
InxAl1−xAs/InyAl1−yAs vertical superlattices (VS) were naturally formed by phase separation during the growth of InAlAs/InP layers at temperatures in the range 565–615 °C by metalorganic chemical vapor deposition. The VS lies perpendicular to the (001) growth plane. As the growth temperature increased from 565 to 615 °C, the VS decreased in thickness from ∼15 to ∼6 nm, and became less planar and uniform. Transmission electron diffraction results showed the occurrence of CuPt-type ordering in some of the layers. Band-gap reduction of ∼300 meV was observed in the InAlAs layers grown at temperatures ranging from 565 to 615 °C. Such a large reduction in band-gap energy was attributed to combined effects of the VS and CuPt-type ordering.