Selective area growth of Ga‐polar GaN nanowire arrays by continuous‐flow MOVPE: A systematic study on the effect of growth conditions on the array properties

Site‐controlled growth of GaN nanowires (NWs) on GaN‐on‐sapphire templates with a patterned SiN mask has been carried out by metalorganic vapor phase epitaxy using a continuous‐flow growth mode. A low V/III ratio compared to that used for GaN layer growth, combined with low precursor flow rates for both Ga and N precursors, has been used to promote the nanowire growth on Ga‐polar substrates. The lateral growth rate, that is, perpendicular to the c‐axis, could be further controlled using appropriate growth temperatures and H2/N2 ratios. Besides, the influence of the pattern geometry on the nanowire aspect ratio and size homogeneity has been addressed.