LAQUANI has developed the Epitaxial lateral overgrowth (LOG) of GaN on patterned GaN/Sapphire substrates to produce GaN epilayers with reduced dislocation densities. The growth of single crystal GaN substrates, the development of the most appropriate epitaxial growth technique and the identification of the most suitable heterostructure represent the hard core of this study.
To reach the final target of producing GaN based lasers, MOVPE and GSMBE growth techniques were used in this program with specific goals. MOVPE has been shown to produce good quality layers and efficient devices, however p-type doping requires activation steps. GSMBE allows growth at lower temperatures and p-type doping without annealing steps. The most appropriate epitaxial technique will be used for laser structure fabrication.
During this project, the consortium has demonstrated its expertise in growing HVPE GaN subtrates on 2" wafers, ELO GaN on 1" wafers and nitride based heterostructures and QWs. Henceforth the way is paved for the production of such substrates and structures in Europe.