We describe a simple way of producing adherent metal films (Cu or Ni) on insulator surfaces [SiO2, glass, or polyphenylquinoxaline (PPQ), an insulating polymer] by electroless growth on a thermally activated palladium acetylacetonate [Pd(acac)2] seeding layer. Using this process, we produced tiny metal patterns on insulators by localized laser pyrolysis (using either a pulsed Cu vapor or a cw Ar+ laser) of the spun-on seeding layer. A tensile stress test applied to a Ni deposit on SiO2 reveals bonding strengths as high as 2 N/mm2. The mechanisms of such an increased adherence have been studied using x-ray photoemission spectroscopy (XPS). The critical role of the chemical environment of the Pd clusters obtained by pyrolytic decomposition of the Pd(acac)2 seeding layer is shown. In particular, XPS reveals that most of the Pd atoms left at the surface after thermal decomposition still remain bonded to an organic aromatic species identified as one of the two acetylacetonate ‘‘wings’’ of the parent molecule. A wear-resistant metal deposit on insulators can only be formed when these remaining ligands are removed by an additional acetic acid treatment.

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In this work, x-ray photoemission spectroscopy is performed on standard polyphenylquinoxaline surfaces treated by ultraviolet irradiation under oxygen atmosphere and by plasma. Spectra reveal the appearance of oxidized carbon species and of amine, NH+3 or NO groups, indicating that polymer bonds are broken during the treatments. Interaction of chromium with these surfaces is further reported. A solid-state reaction occurs, where the new species produced by the treatments are reduced, and chromium oxide, as well as nitrogen and carbon electron-rich species are formed.

Monochromatized x-ray photoelectron spectroscopy, contact angle measurements, and peeling tests have been used to investigate the physicochemical surface properties of polyphenylquinoxaline (PPQ) and of copper-PPQ interfaces. The surface composition and oxygen content of a polymer that was deliberately oxidized by ultraviolet exposure in air were determined, and monitored during the anneal (up to 400 °C) of this thermostable polymer. Subsequent copper deposition in the monolayer range and film growth is characterized by small cluster formation, before percolation into a conducting metallic layer. Further anneal of the Cu-PPQ interface is seen to promote diffusion of Cu into the polymer, and to catalytically degrade the interface by oxidizing the polymer. These observations are correlated with peeling test measurements on the same Cu-PPQ interfaces: UV treatment combined with an anneal process are shown to be deleterious to the mechanical properties of the interface.