Supercritical fluid chemical deposition of Cu in Ru and TiN-lined deep nanotrenches using a new Cu(I) amidinate precursor

We report supercritical fluid chemical deposition (SFCD) of Cu films in Ru- and TiN-lined deep nanotrenches using a new non-fluorinated Cu(I) amidinate precursor. The Cu(l) amidinate precursor dispersed well in an acetone/CO2 solution with molecular hydrogen as the reducing agent at very low temperatures. High-purity Cu films were grown on both Ru and TiN substrates at a lower deposition temperature (140 degrees C) than typical temperatures reported for Cu-II(hfac)(2) and Cu-II(dibm)(2) precursors. The temperature dependence of the growth rate was studied and the growth rates were determined to be 10-14 nm/min and 6-13 nm/min for Ru and TiN substrates, respectively, in a temperature range of 140-240 degrees C. On the Ru surface, Cu nucleated densely, forming smooth, strongly adherent films. At 140 degrees C, the excellent filling capability of Cu in Ru- or TiN-lined nanotrenches was demonstrated. (C) 2014 Elsevier B.V. All rights reserved.