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

Abstract

A comparative study of O 3 and H 2 O as oxidizers for atomic layer deposition (ALD) HfO x and AlO x thin films was carried out employing a 300-mm wafer capable ALD cluster tool. TEMAHf (tetrakis-ethylmethylamino-hafnium) and TMA (trimethylaluminium) 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.