STATIC SIMS INVESTIGATION OF METAL-POLYMER INTERFACES

The formation of the interface between thermally evaporated metals (al uminium, copper) and polymers [poly(ethylene terephthalate) (PET), pol y(methyl methacrylate) (PMMA)] has been investigated by static SIMS. T wo generations of instrument have been used. The first one, using a qu adrupole mass spectrometer directly connected to the same ultrahigh va cuum environment as the metallization chamber, has allowed an in situ characterization of the interface formation after each metal depositio n in the submonolayer regime. The second system, using a time-of-fligh t (ToF) mass spectrometer, has allowed ex situ analyses of Al/PET, Cu/ PET, Al/PMMA and Cu/PMMA interfaces. The high mass resolution of the T oF spectrometer led to the unambiguous identification of the molecular fragments that are characteristic of polymer-metal interaction. The r esults show that Al atoms react with the oxygenated parts of PET and P MMA. This interaction limits the lateral diffusion of Al atoms on the polymer surface and, consequently, induces a two-dimensional growth of the Al film on these polymer substrates. In the Cu deposition case, a weaker metal-polymer interaction is observed. This leads to Cu cluste ring and a three-dimensional growth. Time-of-flight SIMS molecular ima ging clearly reveals Cu clusters on the PMMA surface.