Defect density reduction of the Al2O3/GaAs(001) interface by using H2S molecular beam passivation

► We are reporting the Molecular Beam Passivation of GaAs(001) using in situ H2S. ► An in situ deposited Al2O3 layer has been used as high-κ dielectric. ► We showed that in situ H2S surface treatment leads to a stable oxide/III-V interface. ► The passivation comes from the improved structural properties of the GaAs surface.