Applied Physics Letters · 2006 · 15 citations · 17 references
Spacer Layer ThicknessEngineeringSemiconductor NanostructuresQuantum MaterialsNanostructure SynthesisMolecular Beam EpitaxyNanoscale ScienceEpitaxial GrowthMaterials ScienceNanoscale SystemPhysicsNanotechnologyInalas Spacer LayersAlloy Phase SeparationNanocrystalline MaterialNanophysicsNanomaterialsSpatial Correlation ControlApplied PhysicsCondensed Matter Physics
The control of shape and spatial correlation of InAs-InAlAs-InP(001) nanostructure superlattices has been realized by changing the As overpressure during the molecular-beam epitaxy (MBE) growth of InAs layers. InAs quantum wires (QWRs) are obtained under higher As overpressure (1×10−5Torr), while elongated InAs quantum dots (QDs) are formed under lower As overpressure (5×10−6 or 2.5×10−6Torr). Correspondingly, spatial correlation changes from vertical anti-correlation in QWR superlattices to vertical correlation in QD superlattices, which is well explained by the different alloy phase separation in InAlAs spacer layers triggered by the InAs nanostrcutures. It was observed that the alloy phase separation in QD superlattices could extend a long distance along the growth direction, indicating the vertical correlation of QD superlattices can be kept in a wide range of spacer layer thickness.
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