ABSTRACT
Abstract Hyperthermal fluorine atomic beam interaction with PMDA-ODA polyimide (PI) has been studied. It was found that CF, CF2 and CF3 groups were formed by reaction of PI with atomic fluorine with an impingement energy of 11.7 eV. Advancing contact angle of water increases rapidly to 100◦, followed by a slow increase due to the increase in surface roughness. A gasification reaction of PMDA-ODA was observed under hyperthermal atomic fluorine exposure, and the erosion yield was of the same order of magnitude as that by atomic oxygen. Surface analysis results of atomic fluorine-exposed highly oriented pyrolytic graphite (HOPG) using synchrotron radiation photoelectron spectroscopy showed that the fluorine concentration was limited to only topmost HOPG (0 0 0 1) layer. From the HOPG experiment, it is revealed that the physical sputtering effect can be ignored in this hyperthermal atomic beam process and fluorination reaction was restricted only to the topmost graphite layer.
