| AVS 56th International Symposium & Exhibition | |
| Plasma Science and Technology | Tuesday Sessions |
| Session PS-TuA |
| Session: | Fundamentals of Plasma-Surface Interactions I |
| Presenter: | E.H. Lock, Naval Research Laboratory |
| Authors: | E.H. Lock, Naval Research Laboratory S.G. Walton, Naval Research Laboratory R.F. Fernsler, Naval Research Laboratory M. Baraket, Naval Research Laboratory |
| Correspondent: | Click to Email |
Electron beam generated plasmas constitute a unique class of plasmas due to their intrinsic low electron temperatures (< 1 eV), plasma potentials and thus ion kinetic energies. For the treatment of polymers, these plasmas have demonstrated the ability to change the surface energy and chemistry with limited change in surface topography and low etch rates. Successful increase in surface energy was achieved as a result of argon, oxygen and nitrogen treatments due to incorporation of oxygen and nitrogen functionalities. Treatment with SF6 resulted in decrease of surface energy due to incorporation of fluorine groups. The surfaces were unchanged or even made smoother after argon and nitrogen treatments. Plasma generation in more aggressive media including oxygen and SF6 resulted in surface roughness increase.
The dominant species driving the chemical modification process in electron beam generated plasmas differ from the ones observed in the conventional plasma sources because the high energy electron beam ionizes the gas much more efficiently and thus produces a significantly larger proportion of ions. Thus, the influence of metastables and photons is limited.
This study addresses the question of the influence of the increased kinetic energy and ion fluxes on the polymer surface modification. Ultra thin polystyrene film was chosen as a model substrate due to its well understood behavior. The changes in surface energy, chemistry, etch rates and glass transition temperatures of the polymer were investigated. The chosen gas environments are pure argon and argon/oxygen mixtures. Argon allows for studying the effects of surface activation and physical sputtering. In argon/oxygen mixtures the influence of reactive species is critical for the surface modification processes.This work was supported by the Office of Naval Research. E. H. Lock and M. Baraket appreciate the support of the National Research Council.