Soft x-ray photoemission study of the thermal stability of the Al2O3/Ge (100) interface as a function of surface preparation.

The high temperature thermal stability of ultra-thin atomic layer deposited Al2O3 on sulphur passivated and hydrofluoric acid (HF) treated germanium surfaces was studied using soft x-ray photoemission spectroscopy. The interface sulphur component was stable up to 500 °C vacuum annealing. The interfacial oxides were completely removed at 600 °C for the sulphur passivated sample, whereas HF treated sample showed traces of residual oxides at the interface. However, this annealing treatment does not show any significant change in Al2O3 stoichiometry. The dielectric-semiconductor band offsets were estimated using photoemission spectroscopy measurements. [ABSTRACT FROM AUTHOR]