Indium Surfactant Assisted Growth of AlN/GaN Heterostructures by Metal-Organic Chemical Vapor Deposition

AlN/GaN single and multi-layer structures were grown by metal-organic chemical vapor deposition. Step flow growth of AlN was achieved by addition of trimethylindium to the growth ambient, which enhanced the surface mobility of adsorbed Al-species. For AlN/GaN multi-layer structures, electron mobilities of 9900 cm2/Vs at a sheet carrier density of 1.2 × 1013 cm—2 were measured at 77 K, which is significantly higher than the values observed for AlGaN/GaN heterostructures at comparable sheet carrier densities.