In-situ characterization of Ga2O passivation of In0.53Ga0.47As prior to high-k dielectric atomic layer deposition

Ga2O interfacial passivation layers (IPLs) on In0.53Ga0.47As are investigated using in-situ monochromatic x-ray photoelectron spectroscopy. The oxide is entirely composed of Ga2O when deposited with an effusion cell temperature of 1500 °C and substrate temperature of 425 °C. The growth on In0.53Ga0.47As reveals slight chemical modification of the surface. The Ga2O behavior and ability to protect the III-V surface are observed following Al2O3 deposition by atomic layer deposition following each precursor pulse. Al2O3 growth by trimethyl-Al (TMA) and water reveals that the IPL undergoes the “clean-up” effect following TMA exposures causing As-As bonding formation resulting in a high interface state density.