Microstructures of SiO2 and TiOX films deposited by atmospheric pressure inductively coupled micro-plasma jet

Atmospheric-pressure inductively coupled micro-plasma jet was used for deposition of SiO2 and TiOx thin films. Si and Ti alkoxides respectively were vaporized into Ar gas to be decomposed thermally in the Ar plasma jet, being deposited as the metal oxide films. Microstructures of the films were investigated as changing the plasma conditions such as Ar gas flow rate and concentration of the alkoxides in Ar gas. The SiO2 and TiOx films deposited at higher Ar gas flow rates were composed of particles of micron or submicron sizes. The SiO2 film was composed of a single layer of the particles and the particles sometimes formed unique aggregation structures. On the other hand, the TiOx film had a structure in which the particles were piled up randomly. The structures suggested that the SiO2 particles grew on the substrate whereas TiOx particles were formed in plasma gas phase.