UC Santa Barbara

The growth and the electrical properties of HfO2 / In0.53Ga0.47As interfaces are characterized as a function of exposure to trimethylaluminum TMA prior to chemical beam deposition of HfO2 from an alkoxide precursor. It is shown that TMA can act as a surfactant for HfO2 growth for 2x4 but not for the group-III-rich 4x2 reconstructed surfaces. The Fermi-level can be unpinned by postdeposition forming gas anneals only for interfaces that were exposed to low doses of TMA at low temperatures. The results are discussed in the context of the interaction between TMA and III-V surfaces.