Half-cycle atomic layer deposition reaction studies of Al2O3 on In0.2Ga0.8As (100) surfaces

Abstract

The reduction in III–V interfacial oxides by atomic layer deposition of ${\text{Al}}_2{\text{O}}_3$ on InGaAs is studied by interrupting the deposition following individual trimethyl aluminum (TMA) and water steps (half cycles) and interrogation of the resultant surface reactions using in situ monochromatic x-ray photoelectron spectroscopy (XPS). TMA is found to reduce the interfacial oxides during the initial exposure. Concentrations of Ga oxide on the surface processed at $300°\text{C}$ are reduced to a concentration on the order of a monolayer, while ${\text{AsO}}_x$ species are below the level of detection of XPS.