Advanced Materials Research Vols. 516-517

Abstract: The (NH₄)₂ S treatment was used for the reduction of native oxides and passivation on GaAs. Atomic layer deposited Al₂O₃ can further remove the residue native oxides and lower the leakage current on (NH4)2S treated GaAs from self-cleaning and high bandgap. For further stacked with high dielectric constant TiO₂ also prepared by atomic layer deposition on Al2O3/(NH4)2S treated p-type GaAs MOS capacitor, the leakage currents can reach 1.9 × 10^-8 and 3.1 × 10^-6 A/cm2 at ± 2 MV/cm. The dielectric constant is 25.