Morphology Evolution of Pulsed-Flux Ga-Polar GaN Nanorod Growth by Metal Organic Vapor Phase Epitaxy and Its Nucleation Dependence

Abstract

We fabricated selectively grown Ga-polar GaN nanorods by optimizing metal organic vapor phase epitaxy (MOVPE) growth parameters using continuous-and pulsed-mode approaches. Nucleation layers were grown using continuous mode with H-2 or N-2 as carrier gas, which resulted in pyramidal or hexagonal shapes, respectively. The growth mechanism of nanorods was further studied for the nucleation layer grown with the H-2 case, in which the pyramidal shape of the nucleation layer was observed to be flattened during the initial step of pulsed-mode growth and then evolved into nanorods by Ga clustering on the top c-plane. (C) 2013 The Japan Society of Applied Physics