HYDROGEN STORAGE, MICROSTRUCTURAL PROPERTIES OF, AND ELECTROMIGRATION EFFECTS IN AL/PD/AL FILMS

Composite Al/Pd/Al films were thermally evaporated onto SiO2 in an ultrahigh vacuum environment. The thickness of the Pd layer was varied in the range of 0-66 angstrom. The Pd layer was exposed to various partial pressures of H2 in situ. Secondary ion mass spectrometry showed that the amount of hydrogen dissolved in the Pd layer depended on the thickness of the Pd layer exposed. Transmission electron microscopy revealed that the grain structure of the composite films became more complex with the addition of Pd to the structure. The electromigration resistance of the films increased with the incorporation of even the thinnest of Pd layers. However, no beneficial effect due to the hydrogen dissolved in the Pd layer was evident.