The properties of Al2O3 films were investigated after dipping the films in DI-water. The thickness of the films did not change due to formation of Al-hydroxide layer on their surfaces. After dipping in DI-water, the dielectric constant of the Al2O3 film increased and this seems to be caused by a structural change of the film surface. Using this phenomenon, the overall dielectric constant which includes an Al2O3 layer can be raised easily through a simple treatment.

Keywords: Al2O3, Al-hydroxide, dielectric constant, hydration, structural change