A Comparison of O3 and H2O as Oxygen Sources for Atomic Layer Deposition Processing of HfAlOx Thin Films for High-k Dielectric Nanocapacitor Applications

Abstract

A comparative study of O3 and H2O as oxidizers for atomic layer deposition (ALD) HfOx and AlOx thin films was carried out employing a 300-mm wafer capable ALD cluster tool. TEMAHf (tetrakis-ethylmethylamino-hafnium) and TMA (trimethyl-aluminium) were used as metal precursors. Process conditions were varied to evaluate the effects on unary metal oxide growth as an approach towards developing a mixed-phase binary metal oxide growth process. Films were characterized using scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS), Rutherford backscattering spectroscopy (RBS), and capacitance measurements of MOS capacitor structures. Initial testing results of the electrical properties of resulting binary metal oxides will be discussed.