Deposition of SiOx Thin Films by Corona Discharges at Atmospheric Pressure

The corona discharge (also called dielectric barrier discharge) is a non-thermal transient gas discharge which can be operated at atmospheric pressure. A novel application of corona discharges is the deposition of thin films. Depending on the gas composition in the gap between the electrodes different thin film materials can be deposited on substrates placed on the electrodes. SiOx thin films were deposited on silicon wafers using tetramethylsilane (TMS) as the precursor. The deposition rate was optimised by the variation of the precursor concentration and the gas flow velocity. Furthermore, the influence of pulsed corona discharges on the deposition rate were investigated and compared to continious corona discharges. Different types of sinusoidal voltage pulse were applied.