Selective Area Growth of GaAs Nanowires and Microplatelet Arrays on Silicon by Hydride Vapor-Phase Epitaxy

In this work, we demonstrate the growth of vertically oriented GaAs nanowires (NWs) and microplatelets directly on a patterned SiO2/Si(111) substrate by hydride vapor-phase epitaxy (HVPE). Direct condensation of GaAs on Si was achieved through a critical surface preparation under an As-controlled atmosphere. GaAs NWs were grown along the ⟨111⟩B direction with a hexagonal cross section when the hole opening diameter (D) in the SiO2 mask was below 350 nm. Larger apertures (D ≥ 500 nm) resulted in uniform microplatelets. This study highlights the capability of HVPE for selective area growth of GaAs directly on Si and thus the potential of HVPE as a generic heterointegration process for III-V semiconductors on silicon.