Effects of Ar- and Ar/O2-plasma-treated amorphous and crystalline polymer surfaces revealed by ToF-SIMS and principal component analysis

The effects of argon (Ar) and a mixture of Ar and oxgyen(Ar/O2) plasmas on amorphous and semi-crystalline poly(bisphenol A hexane ether) thin films were investigated by time-of-flight secondary ion mass spectroscopy (ToF-SIMS) and principal component analysis (PCA). PCA results of the ToF-SIMS spectra indicate that an Ar/O2 plasma produced less physical sputtering and had a higher chemical reactivity than did an Ar plasma, regardless of whether an amorphous or a crystalline surface was involved. However, the chemical differences between the Ar- and Ar/O2-plasma-treated semi-crystalline films were much smaller. The observed results can be explained by the higher resistance of the polymer crystalline regions to physical sputtering and chemical etching. Copyright (c) 2013 John Wiley & Sons, Ltd