Epitaxial Lateral Overgrowth of GaN in Large Area MOCVD Reactors

A successful large area ELO GaN process technology will lead to a low cost 'virtual substrate' for LED and high performance III-N based devices. We propose to investigate the application of this technique in large area III-Nitride MOCVD reactors, up to 42x2 sapphire and silicon substrates; the latter as a low cost alternative to sapphire for high volume/low cost devices. EMCORE will investigate the use of both SiOx and SiNx mask layers on sapphire and silicon substrates. In addition to process parameters such as V/III ratio and growth pressure, novel use of surfactants and SiNx based mask layers, will be investigated in order to optimize the ELO technique in EMCORE large area MOCVD reactors. Materials and devices grown by ELO will be characterized in order to quantify the effectiveness of the dislocation reduction in the structures. Special attention will be paid to characterization of InGaN MQW structures as well as p-GaN and p-AIGaN grown with ELO GaN as the virtual substrate on both sapphire and silicon. LED's from the U V to blue, as well as W photodetectors, with be fabricated on ELO GaN films and the device performance fully characterized.