A RHEED investigation of self‐assembled GaN nanowire nucleation dynamics on bare Si and on Si covered with a thin AlN buffer layer

Abstract

Abstractmagnified imageBased on reflection high energy electron diffraction (RHEED) experiments, we show that the nucleation delay of GaN nanowire growth by plasma‐assisted molecular beam epitaxy on nitrided Si(111) and on AlN/Si(111) exhibit similar behaviors in function of the substrate temperature and of the Ga flux. On bare Si(111), a finite delay, estimated to be one minute in our system and under our set of growth conditions, is necessary to form and subsequently amorphize crystalline β‐Si3N4 before GaN can start to form. Although the amorphization time is found to be independent of the substrate temperature, this process adds a supplemental delay within the overall delay in the growth of GaN nanowires on bare Si(111), compared to growth on AlN/Si(111) or on amorphous silicon nitride on Si(111). (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)