Adhesion mechanism of copper films deposited by magnetron sputtering on polyamide composites

This paper presents a study of the interface between Cu and a glass fibre reinforced PAMXD 6 polymer. Substrate surface chemistry was characterised before metallisation by spectroscopic techniques including Fourier transform infrared and X-ray photoelectron spectroscopy (XPS). Chemical bonding of Cu layers (20 nm to 2 11mthick) to the polymer was investigated by XPS (depth profiling, argon ion bombardment) and secondary ion mass spectrometry. The results showed that Cu reacts with the polymer, leading to the formation of a Cu-O-C like interfacial compound, and illustrated the influence of the evaporation pressure and temperature parameters on the interfacial structure and final quality of the film. The adhesion strength of the coating, obtained by z axis tensile tests (studs bonded to the PAMXD 6 with an epoxy glue), confirmed the interpretation of the analyses.