Growth of GaN on (0001) sapphire by MOCVD using a multilayer approach in a closed space showerhead reactor

Summary form only given. In this talk, we will discuss dependance of this growth mode on various reactor parameters including reactant flows, carrier gas, rotation speed and separation between the showerhead and substrate. These parameters all effect the hydrodynamics and chemical reaction pathways of this unique reactor design. We will discuss how the growth conditions affect the formation of the three dimensional islands and now the variation in the density and the size or the islands at the initial stages of overlayer growth affect the coalescence of the islands and the surface morphology and electrical, structural and optical quality of the GaN overlayer.