Passivation of GaAs using (Ga2O3)1−x(Gd2O3)x, 0⩽x⩽1.0 films

The Ga2O3(Gd2O3) dielectric film was previously discovered to passivate the GaAs surface effectively. We have investigated the systematic dependence of the dielectric properties of (Ga2O3)1−x(Gd2O3)x on the Gd (x) content. Our results show that pure Ga2O3 does not passivate GaAs. Films with x⩾14% are electrically insulating with low leakage current and high electrical breakdown strength. Furthermore, a low interfacial density of states was attained in films with x⩾14%. The results show the important role of Gd2O3 in the (Ga2O3)1−x(Gd2O3)x dielectric films for effective passivation of GaAs.