Quantum Wires on Vicinal GaAs (110) Surfaces

MBE growth of GaAs on GaAs (110) surfaces has been reported not to provide smooth surface morphology due to columnar growth of epitaxial layers [1]. Highly faceted surfaces are observed for MBE growth on (110) surfaces. Only vicinal (110) surfaces misoriented 6° toward (111)A have provided device quality GaAs layers [2]. However, when GaAs/AlGaAs superlattices are grown on vicinal (110) surfaces misoriented toward (111)A, quantum wire-like (QWR-like) structures have been observed [3,4]. These QWR-like structures are induced by the formation of coherently aligned giant growth steps and remarkable composition and thickness modulation of AlGaAs and GaAs layers at the giant step edges. Using these phenomena, A1GaAs and GaAs quantum wires (QWRs) have been formed on vicinal (110) surfaces misoriented toward (111)A.