Enhanced Barrier and Optical Properties of Inorganic Nano-Multilayers on PEN Substrate Through Hybrid Deposition

In this study, an inorganic multilayer barrier film was fabricated on the polyethylene naphthalate (PEN) substrate, which was composed of a SiO₂ layer prepared by inductively coupled plasma chemical vapor deposition (ICP-CVD) and a Al₂O₃/ZnO nanolaminate produced by plasma-enhanced atomic layer deposition (PEALD). The multilayer composite film with a structure of 50 nm SiO₂ + (4.5 nm Al₂O₃/6 nm ZnO) × 4 has excellent optical transmittance (88.1%) and extremely low water vapor permeability (3.3 × 10^-5 g/m²/day, 38 °C, 90% RH), indicating the cooperation of the two advanced film growth methods. The results suggest that the defects of the SiO₂ layer prepared by ICP-CVD were effectively repaired by the PEALD layer, which has excellent defect coverage. And Al₂O₃/ZnO nanolaminates have advantages over single-layer Al₂O₃ due to their complex diffusion pathways. The multilayer barrier film offers potential for encapsulating organic electronic devices that require a longer lifespan.