Event Details

III-V and III-N Semiconductor Nanostructures by Molecular Beam Epitaxy

Abstract:

In the first part of the seminar I will present the self-assembling of semiconductor nanostructures on GaAs substrates with <631> crystal orientation. Growth by molecular beam epitaxy on this high-index plane allowed us to obtain highly ordered nano-facets useful for the self-assembling of 1D structures. Quantum wire (QWR)-like confinement in GaAs/AlAs heterostructures was achieved as deduced from polarized PL spectroscopy. Furthermore, MBE growth of GaAs on <631> substrates allowed us the formation of bifurcated nanowires defining Y-shaped nanostructures with suitable dimensions for applications in three-terminal ballistic nano-junctions.

The second part of the seminar will be dedicated to present the results of MBE growth of GaN with cubic metastable phase. Growth of cubic GaN with a low density of hexagonal phase inclusions was achieved on GaAs<001> substrates employing an appropriate buffer layer. Cubic n-GaN/p-GaAs heterojunctions were fabricated and tested as photovoltaic devices and radiation detectors.