Growth of SiO_2 and TiO_2 thin films deposited by reactive magnetron sputtering and PECVD by the incorporation of non-directional deposition fluxes

摘要

We have deposited TiO_2 and SiO_2 thin films by techniques as different as plasma-enhanced chemical vapor deposition (PECVD) and reactive magnetron sputtering under experimental conditions where highly directional deposition fluxes are avoided. The results indicate that whatever the deposition technique employed or even the precursor gas in the PlvCVD technique, films share common microstructural features: a mounded surface topography and a columnar arrangement in the bulk, with the column width growing linearly with film thickness. With the help of a Monte Carlo model of the deposition, we conclude that these common aspects are explained by solely taking into consideration the incorporation of a low-energy, isolropically directed, deposition flux onto a substrate at low temperature and under a weak plasma/surface interaction environment.