Gas barrier and mechanical properties of a single-layer silicon oxide film prepared by roll-to-roll PECVD system

We presented a single-layer silicon oxide (SiOx) barrier film with excellent moisture barrier performance and flexibility. High quality, continuous, and large-area barrier film was deposited on polyethyleneterephthalate substrate using a roll-to-roll PECVD for large-scale production. The effects of the reaction gas flow ratio of N ₂ O/SiH ₄ (R) on the characteristics of the SiOx film were systematically analyzed in terms of the optical properties, surface roughness, film density, hardness, chemical composition, and water vapor transmission rate. The SiOx film exhibited the best film density, hardness, surface roughness, and superior barrier performance of 1.6 × 10 ⁻³ g · m ⁻² · d ⁻² at R = 1.5. The SiOx barrier film also exhibited excellent flexibility which bent up to 2 mm and withstood the repeated bending of 10 000 cycles.