Hydrogen permeation through uniaxially strained SiOx barrier thin films photochemically prepared on PET foil substrates

Hydrogen permeation through uniaxially strained thin SiOx x based gas barrier films, formed at room temperature and ambient pressure on PET foil substrates by UV photochemical conversion (Photoconversion), was investigated using a dedicated measurement system. Hydrogen permeation measurements were conducted as a function of the stack of laminated single SiOx x barrier films, of the sample temperature as well as of the uniaxial mechanical strain applied to the samples. The results demonstrate a significant overall improvement of the hydrogen barrier properties for both single SiOx x barrier films on PET and laminated single SiOx x barrier films on PET. In the case of strained samples, the hydrogen barrier properties deteriorate due to stress-induced crack formation in the barrier films. This deterioration is strongest for strained single SiOx x barrier films but can be substantially reduced by laminating single SiOx x barrier films.