GaN MIS Capacitors with Photo-CVD SiN[sub x]O[sub y] Insulating Layers

We report the deposition of high-quality and layers onto GaN/sapphire templates by photochemical vapor deposition (photo-CVD). It was found that the root-mean-square roughness observed from the photo-CVD layer was much smaller than that observed from photo-CVD layer with the same thickness. GaN metal-insulator-semiconductor (MIS) capacitors with these insulating layers were also fabricated. With an applied electric field of , it was found that the leakage current densities were and for the capacitors with photo-CVD and photo-CVD insulating layers, respectively. It was also found that the breakdown field of the capacitors with photo-CVD could reach . The interface state density at the interface was also found to be reasonably low.