Atomic layer deposition of SiO 2 from Tris(dimethylamino)silane and ozone by using temperature-controlled water vapor treatment

Abstract

Atomic layer deposition of SiO 2 from tris(dimethylamino)silane (TDMAS) and ozone as precursors on Si(100) surfaces at near-room temperatures was studied by infrared absorption spectroscopy with a multiple internal reflection geometry. TDMAS can be adsorbed at OH sites on hydroxylated Si surfaces at room temperature. Ozone oxidation of the TDMAS-treated Si surface is effective in removing hydroaminocarbon adsorbates introduced during TDMAS adsorption at room temperature. After oxidation by ozone, treatment with H 2O vapor at a substrate temperature of around 160 °C causes regeneration of OH sites for TDMAS adsorption. Cycles involving TDMAS adsorption and ozonization at room temperature followed by H 2O treatment at 160 °C permit the buildup of layers of SiO 2. The amount of residual hydroaminocarbon at the interface between the growing SiO 2 film and the substrate can be reduced with the ozone treated Si surface as a starting surface.