Comparison of surface morphologies of SiO 2 films prepared by ion-beam induced chemical vapor deposition and ion-beam assisted deposition

Abstract

The surface topographies of silicon dioxide films prepared by low-energy ion-beam induced chemical vapor deposition (IBICVD) and ion-beam assisted deposition (IBAD) were studied using an atomic force microscopy (AFM). In the case of IBICVD, when prepared using bubbled hexamethyldisiloxane (HMDSO) and assisted O 2 gas under irradiation of 150 eV Ar ions, the root mean square (RMS) of the surface roughness of the film was 2.0 nm. However, when prepared using the bubbled HMDSO under irradiation of 150 eV oxygen ions, the RMS deduced to 0.25 nm. In the case of IBAD, when deposited using evaporated silicon monoxide under irradiation of 150 eV oxygen ions, the RMS was 0.20 nm. As a reference, the RMS of fused silica was changed from original 0.70–0.40 nm after irradiated of 150 eV oxygen ions. It is concluded that low-energy oxygen ion bombardment not only promotes chemical reaction and dissociation of precursor but also leads to a smooth surface due to reactive ion beam etching on the film surface.