AlGaAs MBE Growth and Formation of Quantum Wire Structures on Vicinal GaAs (110) Surfaces.

Quantum wire-like structures are formed in the AlGaAs/GaAs superlattices grown on vicinal GaAs (110) surfaces by MBE. SEM and EPMA observations reveal that the formation of giant steps and orientation dependent AlAs mole fraction of AlGaAs layers induce the quantum wire-like structures. Using RHEED, it is found that the step structures of AlGaAs surfaces depend on growth temperatures (diatomic steps above 600°C, giant steps below 600°C), while all the GaAs and AlAs surfaces consist of regular arrays of diatomic steps. Using this phenomenon, quantum wire structures are naturally formed by growing AlAs/A1GaAs/AlAs quantum wells on vicinal GaAs (110) surfaces with giant growth steps. The photoluminescence strongly polarized parallel to the wire direction gives a clear evidence for the formation of quantum wire structures.