Vol.:(0123456789) Plasma Chemistry and Plasma Processing https://doi.org/10.1007/s11090-019-10049-y 1 3 ORIGINAL PAPER Silicon Oxide Barrier Films Deposited on Polycarbonate Substrates in Pulsed Plasmas Shaham Shafaei 1  · Lanti Yang 1  · Marcel Rudolph 2  · Peter Awakowicz 2 Received: 29 July 2019 / Accepted: 17 November 2019 © Springer Science+Business Media, LLC, part of Springer Nature 2019 Abstract For many applications of polycarbonate (PC) from packaging to micro-electronics improved barrier properties are necessary. In this contribution, silica thin flms were deposited from hexamethyldisiloxane/oxygen (HMDSO/O 2 ) on polycarbonate substrate in three step plasma processes by combining a microwave (MW) surface wave discharge of 2.45 GHz with an optional radio-frequency (RF) bias of 13.56 MHz. The infuence of interlayer thickness, HMDSO fow and oxygen to HMDSO ratio on barrier performance for three step-coating processes was investigated. The morphology and surface properties of the coated surface of PC were studied by atomic force microscopy (AFM). The sur- face topography showed a silica particles distribution on the PC substrate with relatively smooth surface roughness. AFM-QNM provides more insight into the surface morphology and stifness. The results identify the coating structure for PC flm coated with and without bias. High barrier improvement of the deposited flms on PC substrates was obtained after plasma silicon coating process with a barrier improvement factor up to 337. It was found that the deposition process is optimal for food packaging applications by using combined MW-RF PECVD technology. Keywords Plasma technology · Plasma enhanced chemical vapor deposition (PECVD) · Microwave generator (MW) · Radio frequency bias (RF) · Barrier properties · Atomic force microscopy-quantitative nano-mechanical mapping (AFM-QNM) Electronic supplementary material The online version of this article (https://doi.org/10.1007/s1109 0-019-10049-y) contains supplementary material, which is available to authorized users. * Shaham Shafaei shahram.shafaei@sabic.com 1 SABIC, Plasticslaan 1, 4612 PX Bergen op Zoom, The Netherlands 2 Institute of Electrical Engineering and Plasma Technology, Ruhr-University Bochum, 44780 Bochum, Germany