Gas barrier properties of titanium oxynitride films deposited on polyethylene terephthalate substrates by reactive magnetron sputtering
Journal
Applied Surface Science
Journal Volume
254
Journal Issue
11
Pages
3509-3516
Date Issued
2008
Author(s)
Abstract
Titanium oxynitride (TiN x O y ) films were deposited on polyethylene terephthalate (PET) substrates by means of a reactive radio frequency (RF) magnetron sputtering system in which the power density and substrate bias were the varied parameters. Experimental results show that the deposited TiN x O y films exhibited an amorphous or a columnar structure with fine crystalline dependent on power density. The deposition rate increases significantly in conjunction as the power density increases from 2 W/cm 2 to 7 W/cm 2 . The maximum deposition rate occurs, as the substrate bias is -40 V at a certain power densities chosen in this study. The film's roughness slightly decreases with increasing substrate bias. The TiN x O y films deposited at power densities above 4 W/cm 2 show a steady Ti:N:O ratio of about 1:1:0.8. The water vapor and oxygen transmission rates of the TiN x O y films reach values as low as 0.98 g/m 2 -day-atm and 0.60 cm 3 /m 2 -day-atm which are about 6 and 47 times lower than those of the uncoated PET substrate, respectively. These transmission rates are comparable to those of DLC, carbon-based and Al 2 O 3 barrier films. Therefore, TiN x O y films are potential candidates to be used as a gas permeation barrier for PET substrate. © 2007 Elsevier B.V. All rights reserved.
SDGs
Publisher
Elsevier
Type
journal article