화학공학소재연구정보센터
Journal of Adhesion Science and Technology, Vol.15, No.5, 599-612, 2001
Aging of fluorocarbon thin films deposited on polystyrene from hyperthermal C3F5+ and CF3+ ion beams
Fluorocarbon films grown on polystyrene (PS) in vacuum from 25-100 eV CF3+ and C3F5+ ions are aged by exposure to atmosphere for 4 and 8 weeks, then analyzed by X-ray photoelectron spectroscopy. atomic force microscopy, and water contact angle measurements. These fluorocarbon films oxidize with time, showing an increase in their oxygen/carbon ratio and a decrease in their fluorine/carbon ratio. The decrease in fluorine/carbon ratio with aging is due not only to increased oxygen content, but also to surface restructuring and release of low molecular weight oxidized material from the surface. The higher oxidation and surface restructuring observed upon aging for 100 eV C3F5+ and 50 eV CF3+ ion-modified PS can be additionally attributed to higher surface bond breakage and active site formation. 100 eV C3F5+ and 50 eV CF3+ ion-modified PS surfaces are rougher than the 50 eV C3F5+ ion-modified PS. Overall, the aging process of these ion-deposited films appears similar to that of plasma-deposited films.