Effects of aluminum doping on lanthanum oxide gate dielectric films

► We report a method to improve the electrical properties of lanthanum gate oxide. ► Incorporation of aluminum atoms into the oxide results in forming complex oxide. ► We found that a thin Al2O3 was formed at the Si/La2O3 interface. ► The Al2O3 layer suppresses the formation of silicates and silicide bonds. ► Significant reductions on the bulk and interface trap densities were found.