Vertically arrayed Ga-doped ZnO nanorods grown by magnetron sputtering: The effect of Ga contents and microstructural evaluation

► Vertically aligned ZnO:Ga nanorods were grown on sapphire substrates without buffer layers by magnetron sputtering. Preferential growth along the c-axis, resulting in the formation of nanorod arrays without buffer layers. ► Increased stress stored in the ZnO:Ga layers generated a high density of stacking faults. ► Sample doped with a high Ga amount had rotated crystal phases, resulting in rough sidewalls.