Delafossite oxide PtCoO₂ as new conductor for advanced interconnect metallization

Abstract

The delafossite oxide PtCoO2 is a promising candidate metal to replace Cu as an interconnect metal in future technology nodes as it presents a bulk resistivity lower than Al. We have been investigating the deposition of PtCoO2 on c-plane sapphire substrates in a PVD cluster tool. Best epitaxial films exhibit low resistivity with a value of 8.2 μΩcm at 19.2 nm thickness after 800°C post deposition annealing in oxygen atmosphere, lower than our PVD Cu benchmark below 10 nm. Microstructure and surface of the film have been investigated, and integration of epitaxial films will be discussed.