Realization of Atomically Uniform ALD-Al2O3 and TiO2 on SiO2 and GeO2 by UV-Ozone Treatment

Thermally oxidized SiO2/Si and GeO2/Ge are difficult to form very thin oxide films by atomic layer deposition (ALD) due to the chemical inertness of the oxide film surface. In this study, the effect of surface modification of insulating films by the UV-Ozone (UVO) method on ALD was investigated with the aim of controlling the atomic layer thickness and producing a uniform oxide film. The results show that UVO treatment can deposit atomic layer-thick films on SiO2 or GeO2 without delay. This may be due to the formation of dangling bonds on the oxide film surface, which improves the reactivity between the surface and the precursor during initial layer formation.