We attempted to fabricate highly dense Ru thin films by metal-organic chemical vapor deposition at an elevated temperature of 400°C, employing NH3 gas to suppress Ru oxidation. A solution of 0.2 mol/L tris(2,4-octanedionato)ruthenium [Ru(od)3, Ru(C8H 13O2)3] dissolved in n-butylacetate was used as a Ru source and O2 as a reactant gas. It was revealed that NH 3 gas effectively eliminated residual oxygen from the Ru films. However, at higher feeding rates of a metal-organic source, Ru films showed poor densities and high electrical resistivities mainly due to significant carbon incorporation. By optimizing Ru(od)3 flow rate to less than 0.3 g/min to reduce contaminating carbon supply, we successfully produced highly dense and conductive Ru films. The best Ru film had a density of 12.2 g/cm3 and a resistivity of 12.0 μω-cm, which were excellent values close to the bulk ones.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)