On the origin of surface and interface defects associated with the growth of Al-coated thermoplastic heterostacks

By means of a combined microscopy-, spectroscopy-, and tomography-based approach, we investigated surface and interface defects in metal-polymer heterostacks. The aim was to characterize both morphological and compositional alterations of the surfaces, originating in the physical vapor deposition (PVD) growth methods adopted in the fabrication process. Synchrotron radiation X-ray computed tomography (CT) and scanning electron microscopy (SEM) coupled with energy dispersive X-ray Spectroscopy (EDS) indicate that both chemical contaminations, introduced in the fabrication process, and growth conditions strongly affect the presence of defects. On the basis of our results, we classified the defects into four main families. Interestingly, the faults are mainly located at the metal-polymer interface. Thanks to this study, we have been able to gain a deeper insight into the defects' origins and nature, allowing the identification of the precise production steps involved in the generation of the selected defects.