High rate low pressure plasma-enhanced chemical vapor deposition for barrier and optical coatings
Two types of PECVD processes were shown. The main benefits of magPECVD and arcPECVD are their low process pressure of less than 5 Pa which allows the in-line combination with sputtering or evaporation processes. High coating rates could be achieved with both methods, up to 400 nm m/minfor magPECVD and up to 3000 nm m/min for arcPECVD. Optical layer stacks made with magPECVD showed nearly no layer stress. The arcPECVD process showed high process stability with respect to process parameters and layer properties over nearly 2 hours of process time. By using the arcPECVD process for making an interlayer in a permeation barrier stack one achieved at very high web speed of4 m/min a better permeation barrier compared to sputtered layers only with a very good WVTR of 2×10-2 g/m2d, measured at 38°C and 90 % r.h.