Effect of Ag interlayer on the optical and passivation properties of flexible and transparent Al2 O3 Ag Al2 O3 multilayer

We report on the characteristics of a flexible Al2 O3 Ag Al2 O3 multilayer passivation grown on a polyethylene terephthalate (PET) substrate as a function of Ag thickness. Due to the surface plasmon resonance (SPR) effects and the ductility of the Ag layer that is sandwiched between the dielectric Al2 O3 layer, the flexible Al2 O3 Ag Al2 O3 multilayer passivation exhibits a high transparency of 86.44% and improved flexibility at a Ag thickness of 10 nm. We found that SPR effects in the Ag layer occur at the transition region from distinct islands to a continuous film at a critical thickness (∼10 nm). In addition, the water vapor transmission rate of the Al2 O3 Ag Al2 O3 PET sample decreased as the thickness of the Ag layer increased. Using synchrotron x-ray scattering and field emission scanning electron microscopy, we suggest a possible mechanism to explain the SPR in the Ag layer of the flexible and transparent Al2 O3 Ag Al2 O3 multilayer passivation.