Deposition of Cu–Mn alloy film from supercritical carbon dioxide for advanced interconnects

Abstract

Cu–Mn alloy films for microelectronic interconnects were deposited by H2 reduction of bis(2,2,6,6-tetramethyl-3,5-heptanedionato)-copper(II) [Cu(tmhd)2] and bis(penta-methylcyclopentadienyl)-manganese [Mn(pmcp)2] in supercritical carbon dioxide (scCO2). 20-nm thick and continuous Cu–Mn films with a smooth surface were deposited at the temperature of 210 °C. Manganese was found to be segregated to film surface and its content on the surface increased with increasing Mn precursor concentration in scCO2. Mn addition by supercritical fluid deposition could improve surface quality of the Cu film. And electrical resistivity of the Cu–Mn films increased with the Mn contents in the film.