| AVS 61st International Symposium & Exhibition | |
| Thin Film | Thursday Sessions |
| Session TF-ThA |
| Session: | Thin Film for Permeation Barriers and Membranes |
| Presenter: | Sergey Starostin, FOM Institute DIFFER, Netherlands |
| Authors: | S.A. Starostin, FOM Institute DIFFER, Netherlands B.C.A.M. van der Velden-Schuermans, FUJFILM Manufacturing Europe b.v., Netherlands S. Quan, FUJFILM Manufacturing Europe b.v., Netherlands A. Meshkova, FOM Institute DIFFER, Netherlands M.C.M. van de Sanden, FOM institute DIFFER, Netherlands H.W. de Vries, FOM Institute DIFFER, Netherlands |
| Correspondent: | Click to Email |
Atmospheric pressure plasma enhanced chemical vapor deposition (AP PECVD) is attracting steadily growing research interest by having clear benefits in terms of equipment costs, footprint size and possibilities for high throughput in-line processing. However the details of the deposition process and the properties of the synthesized coatings were not studied yet as well as for traditional low pressure PECVD. Recently we have reported that good performing moisture and oxygen silica-like barrier films can be fabricated in atmospheric pressure high current diffuse dielectric barrier discharge [1]. However little is known yet about the dominant gas permeation mechanisms through atmospheric pressure plasma deposited barrier films.
In the present contribution the rates of oxygen and moisture vapor permeation were studied as a function of temperature, film thickness and deposition rate. Activated rate theory was applied to analyze the mechanisms of oxygen and moisture transport through the bilayer system of silica-like film and polymer foil. The experimental value of the apparent activation energy Ea.determines the degree of interaction between permeating gas and the barrier film. If the Eavalues of the bilayer are close to the activation energy of the polymer (47 kJ/mol for moisture), this indicates that the gas transport is controlled by large pinholes with limited or no interaction with the silica film. A transition from polymer controlled moisture permeation to a transport through the silica-like film was observed by tracing an increase in the apparent activation energy from 47 kJ/mol to 80 kJ/mol with film thickness from 2 nm to 100 nm. The gas permeation measurements for the films with different thicknesses were complemented by a detailed morphological study carried out with atomic force microscopy (AFM). The evolution from a non-self-affine morphology of the polymeric substrate to a characteristic smooth surface of the deposited silica-like layer was observed as the film thickness increased from 2 nm to 20 nm. In addition film composition was analyzed by XPS and ATR-FTIR, showing inorganic silica-like character of the deposited layers.
[1] P. Antony Premkumar, S.A. Starostin, M. Creatore, H.W. de Vries, R.M.J.Paffen, P.M.Koenraad, M.C.M. van de Sanden Plasma Process. Polym.,7, 635-639 (2010)