AVS 58th Annual International Symposium and Exhibition
    Plasma Science and Technology Division Wednesday Sessions
       Session PS+SE-WeM

Paper PS+SE-WeM12
Investigation on the Discharge Formation Mechanisms and Surface Analysis of SiO2-like Layers on Polymers Synthesized using High Current Dielectric Barrier Discharge at Atmospheric Pressure

Wednesday, November 2, 2011, 11:40 am, Room 201

Session: Atmospheric Plasma Processing and Micro Plasmas
Presenter: Richard van de Sanden, FOM-Inst. for Plasma Phys. Rijnhuizen & Eindhoven Univ. of Tech., Netherlands
Authors: M.C.M. van de Sanden, FOM-Inst. for Plasma Phys. Rijnhuizen & Eindhoven Univ. of Tech., Netherlands
A. Premkubar, Eindhoven Univ. of Tech. & M2i, Netherlands
S. Starostin, Fujifilm Tilburg, Netherlands
H. de Vries, Fujifilm Tilburg, Netherlands
M. Creatore, Eindhoven Univ. of Tech., Netherlands
Correspondent: Click to Email
The dielectric barrier discharge is recognized as a promising tool for PECVD of thin films at atmospheric pressure. Emerging applications including encapsulation of flexible solar cells and flexible displays requires low costs production of transparent uniform and dense layers with low level of coating defects. Among the two discharges Townsend like discharge (TD) and glow like discharge (GD) the latter offers more flexibility for the high growth rates in plasma enhanced deposition. In this investigation we demonstrate the utilization of glow like discharge in, He free, industrially relevant gas mixture comprising Ar/N2/O2/HMDSO for the deposition of high quality silica like films on large area polymeric substrates (PET or PEN) in a roll-to-roll configuration. While the discharge physics exhibiting the glow like behaviour is investigated via fast ICCD camera, voltage-current waveforms and optical emission spectroscopy, the deposited silica like films is comprehensively analyzed using AFM, SEM, XPS, SE and FTIR. The time evolution of the diffuse atmospheric discharge showed several phases starting from the initial ignition of the low current Townsend-like mode followed by the transition to glow like discharge which then undergoes lateral expansion providing uniform treatment of the whole substrate width. As a generic characteristic of the developed technology, it is observed that, irrespective of precursors (TEOS or HMDSO) and process gases (Ar, N2 or air) employed, the films are smooth, both locally and globally, and of near stoichiometric silica with very low carbon content (< 2%). Detailed AFM morphology description and surface statistical analysis on SiO2 dynamics showed that no film roughening in growth front and lateral directions observed and the synthesized layers (~ 350 nm) grow in a self-similar fashion following the topology of the substrate. The films are uniform with no defects or particle being incorporated during the deposition process and exhibit excellent barrier performances towards O2 and H2O permeation.