Activation of silicon ion-implanted gallium nitride by furnace annealing

Ion implantation into III-V nitride materials is an important technology for high-power and high-temperature digital and monolithic microwave integrated circuits. We report the results of the electrical, optical, and surface morphology of Si ion-implanted GaN films using furnace annealing. We demonstrate high sheet-carrier densities for relatively low-dose (n(atoms) = 5 x 10(14) cm(-2)) Si implants into AlN/GaN/sapphire heteroepitaxial films. The samples that were annealed at 1150 degrees C in N-2 for 5 min exhibited a smooth surface morphology and a sheet electron concentration n(s) similar to 9.0 x 10(13) cm(-2), corresponding to an estimated 19% electrical activation and st 38% Si donor activation in GaN films grown on sapphire substrates. Variable-temperature Hall-effect measurements indicate a Si donor ionization energy similar to 15 meV.