| AVS 54th International Symposium | |
| Plasma Science and Technology | Wednesday Sessions |
| Session PS2-WeA |
| Session: | Plasmas and Polymers |
| 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 |
| Correspondent: | Click to Email |
The activation of polymer surfaces via plasma exposure is one of the most powerful techniques to enhance the bond strength between the polymer surface and molecules, cells and thin films. Even though there are many established plasma techniques for the modification of polymer surfaces, there remain many unresolved questions regarding the most effective use of plasma processing because of the complexity of plasma-surface interactions. In order to guarantee quality and reproducibility of a given plasma process, numerous plasma effects and process parameters need to be taken into account. To ensure the maximum bond strength between a polymer and another material, the chemical and physical changes at the surface need to be well understood. Unfortunately, the conventional plasma sources are limited in their ability to address these problems and the lack of process control leads to problems with efficiency, scalability and material surface damage. Due to its unique characteristics, the electron beam generated plasma system developed at the Naval Research Laboratory allows access to operating conditions not available with traditional plasma methods. This plasma source provides individual control over the plasma parameters including plasma density, ionization region, electron temperature, ion and radical fluxes. Perhaps, the most important advantage of the system is that it minimizes the ion-induced damage to the substrate due to the inherently low plasma potentials. The objective of this work is to study the activation of polystyrene, polyethylene and polypropylene thin film surfaces exposed to plasmas produced in argon and SF6. Argon is inert and should limit surface modification to physical changes through bond breaking. SF6 provides a source of reactive radicals that can directly modify the surface. In both cases a wide range of process parameters was investigated, including pressure, gas flow rate, plasma exposure time, and substrate biasing (to increase ion energy). Ex-situ surface analysis included X-ray photoelectron spectroscopy, atomic force microscopy and various wetting tests are applied to characterize the chemical and physical properties of plasma modified polymer surface.