Comparison of Properties of an Al[sub 2]O[sub 3] Thin Layers Grown with Remote O[sub 2] Plasma, H[sub 2]O, or O[sub 3] as Oxidants in an ALD Process for HfO[sub 2] Gate Dielectrics

Abstract

High- dielectric films were grown by an atomic layer deposition (ALD) technique using and on bare Si and various -passivated Si wafers. The films were grown by different ALD processes using trimethylaluminum as the Al precursor and remote plasma, , and , as the oxidants. The electrical and structural properties of the stacked films were compared. appeared to be the most appropriate oxidant for growing films as the interlayer with superior quality and thermal stability due to its high oxidation power. The stack exhibited an extremely low leakage current density suggesting its significance as a gate dielectric film for future field effect transistors. However, the stacked films with plasma or grown layer showed an unstable flatband behavior and serious charge injection properties that precluded their adoption to metal-oxide-semiconductor field effect transistor devices.