AVS 46th International Symposium
    Plasma Science and Technology Division Wednesday Sessions
       Session PS+SS-WeA

Paper PS+SS-WeA10
FT-IR and XPS Study of Plasma-treated Acrylic Coating Surfaces

Wednesday, October 27, 1999, 5:00 pm, Room 612

Session: Ion-Surface Interactions II
Presenter: M.K. Shi, Battelle Pacific Northwest National Laboratory
Authors: M.K. Shi, Battelle Pacific Northwest National Laboratory
G.L. Graff, Battelle Pacific Northwest National Laboratory
M.E. Gross, Battelle Pacific Northwest National Laboratory
P.A. Mounier, Battelle Pacific Northwest National Laboratory
M.G. Hall, Battelle Pacific Northwest National Laboratory
Correspondent: Click to Email
Polymer/metal multilayer structures have many potential optical, display, and packaging applications. A key issue for the successful processing of such multilayer stacks is obtaining good wetting and adhesion at each interface. Low-temperature plasmas have proven to be one of the most efficient technologies for such purposes. Moreover, the effects of plasma treatments are limited typically to the outermost surface layers and the process is fully compatible with the polymer/metal multilayers cluster tools. We studied the interaction of RF (13.56 MHz)plasmas with an acrylic (tripropyleneglycol-diacrylate)coating surface using FT-IR and XPS. The acrylic coating, with thickness varying from 100 Å to 2 µm, was deposited onto an Al metallized PET substrate by vacuum flash evaporation of the acrylic monomer and subsequent UV-curing. FT-IR measurements showed the destruction of initial ester (O-C=O) and ether (C-O-C) groups, and the ablation of H from C-H bonds after plasma treatments. These effects were accompanied by the formation of carbonyl (R-C=O) and/or acid (R-COOH) groups, and the development of graphite-like C-C structures. The spectral features are similar for N@sub 2@and O@sub 2@ plasma-treated surfaces, no N-containing absorption peaks can be identified for the N@sub 2@ plasma-treated surface. XPS measurements confirmed the loss of the ester (O=C-O) and ether (C-O-C) bonds with respect to the C-C (C-H) peak, and the formation of carbonyl groups. The spectra further showed that approximately 10% of atomic N have been incorporated into the surface after N@sub 2@ plasma treatment. These results showed clearly that FT-IR and XPS are complementary techniques for the characterization of plasma-modified polymer surfaces. The possible plasma/acrylic coating interaction mechanisms will be discussed.