ToF-SIMS characterisation of ultra-thin fluorinated carbon plasma polymer films

In order to create nano-functional fluorocarbon films (CFx films), silicon and polyethylene terephthalate (PET) substrates have been exposed to a pulsed Ar/CHF3 plasma by variation of the deposition time from 10–90 s. The deposited CFx films were analysed using time of flight secondary ion mass spectrometry (ToF-SIMS) and principal component analysis (PCA). Changes in the surface composition and molecular distribution have been detected and correlated to results from additional XPS measurements. The results show differences in film growth and CFx cross-linking for the silicon and PET substrates. In this analysis we demonstrate that ToF-SIMS and multivariate analysis is a very useful combination for thin film characterisation.