Barrier Properties of High Barrier Coating on Plastic Substrate by PE-CVD Roll Coater

摘要

Transparent high barrier coating on a plastic substrate is one of the key technologies for flexible device applications such as OLED and E-paper. We try to approach these applications by using Roll to Roll Plasma Enhanced Chemical Vapor Deposition (PE-CVD) system. A pair of deposition rollers, which holds the film substrate and works as a part of web carrying system, is connected to MF-AC (Medium Frequency Alternative Current) power supply and generated plasma between these rollers. SiO_x barrier coating was deposited on the film substrate by using oxygen and HMDSO (HexaMethylDiSilOxane) mixture as process gasses. The SiO_x coating made by this PE-CVD system was flexible and relatively thick coating up to several microns was deposited on PEN substrate without any cracks or delamination. This paper presents the relation between the film thickness and the WVTR10~(-6)ater vapor transmission rate) under relatively thick coating on two kinds of PEN substrates with different surface conditions. When planarized PEN was used, the improvement from 2 to 4 times barrier property was obtained compared with standard PEN and WVTR of the measuring limit of Aquatran™ (5×10~(-4)g/m~2/day) was able to be obtained half of the film thickness.