The nature of the aluminum–aluminum oxide interface: A nanoscale picture of the interfacial structure and energy-level alignment

Abstract We propose a new structural model for the Al(1 1 1)/Al 2 O 3 (0 0 0 1) interface based on density functional theory calculations. The ultrathin interface structure is shown to consist of two Al layers, one that is oxide-like and the other metal-like. Our model interface reproduces the barrier height to the oxide conduction band edge and predicts the oxide overlayer to lower the metal work function by 0.49 eV.