Effects of In-situ Plasma Treatment on Water-vapor Permeation Barrier Properties Al2O3 Film Prepared by Plasma-enhanced Chemical Vapor Deposition

The effect of in-situ O₂ plasma treatment on the properties of D-CVD grown Al₂O₃ layers was investigated. The Al₂O₃ layers were prepared with a high deposition rate, and their surface roughness, density, stoichiometry, and water vapor permeation barrier properties were evaluated before and after the plasma treatment. The results showed that the O₂ plasma treatment significantly reduced the surface roughness and density of the Al₂O₃ layer, while also curing the pores and defects present on its surface. The treatment led to the migration of Al and oxygen adatoms, resulting in a change in the atomic concentration ratio of Al to O and the formation of a strong bonding structure in the Al₂O₃ layer. Furthermore, the water vapor transmission rate (WVTR) of the O₂ plasma treated Al₂O₃ layer remained low and stable over a prolonged exposure time of 2,500 hours, demonstrating its enhanced water vapor barrier performance. In contrast, the WVTR of the non-treated Al₂O₃ layer increased significantly after 100 hours of exposure. These findings highlight the effectiveness of in-situ O₂ plasma treatment in improving the surface properties and water vapor permeation barrier of D-CVD grown Al₂O₃ layers, making them promising candidates for various applications requiring high barrier properties.