Characterizations of GaN nanowires and GaInN/GaN multi-quantum shells grown by MOVPE

Structural characterizations of core–shell type nanowire-based materials are difficult because of their tiny 3D structure. In this paper, we prepared the GaInN/GaN multi-quantum shell grown on the sidewall of the n-GaN nanowire, and a scanning transmission electron microscope and 3D atom probe are employed for detailed structural characterization of such samples. Furthermore, a cathodoluminescence measurement is carried out for characterization of optical properties. As a result of the 3D atom probe measurement, an out-diffusion-like profile of In was observed. This is considered that the incorporated In atoms in the outer barriers come from In–droplets caused on the top c-plane during the growth of GaInN.