Polycrystalline interlayer formed by deposition of thin-film iridium on silicon

As-deposited iridium-silicon interface structures have been characterized by cross-section high-resolution transmission electron microscopy. Iridium films were deposited by an e-beam gun on (100) Si wafers heated at 200 °C during the deposition. A planar polycrystalline interfacial layer, 2–3 nm thick, was formed between the iridium and the silicon substrate. Thermodynamic calculations are presented which describe the development of the interfacial layer. Correlation between the observed structure and that proposed by thermodynamic calculations is discussed.