Effect of the Ligand Structure on Chemical Vapor Deposition of WN_<i>x</i>C_<i>y</i> Thin Films from Tungsten Nitrido Complexes of the Type WN(NR₂)₃

Tungsten nitrido complexes of the type WN­(NR₂)₃ [NR₂ = combinations of NMe₂, NEt₂, N^<i>i</i>Pr₂, N^<i>n</i>Pr₂, N^<i>i</i>Bu₂, piperidine, and azepane] were synthesized as precursors for aerosol-assisted chemical vapor deposition of WN_<i>x</i>C_<i>y</i> thin films. The effects of the amido substituents on precursor volatility and decomposition were evaluated experimentally and computationally. Films deposited using WN­(NMe₂)­(N^<i>i</i>Pr₂)₂ as a single-source precursor were assessed as diffusion barrier materials for Cu metallized integrated circuits in terms of growth rate, surface roughness, composition, and density. In diffusion barrier tests, Cu (∼100 nm)/WN_<i>x</i>C_<i>y</i> (∼5 nm)/Si samples prepared from WN­(NMe₂)­(N^<i>i</i>Pr₂)₂ were annealed for 30 min at 500 °C and successfully blocked Cu penetration according to four-point probe, X-ray diffraction, scanning electron microscopy etch-pit test, and high-resolution transmission electron microscopy measurements