Atomic layer deposition ͑ALD͒ and pulsed chemical vapor deposition ͑CVD͒ were used to make ruthenium ͑Ru͒ thin films from a volatile Ru amidinate precursor, bis͑N,NЈ-di-tert-butylacetamidinato͒ruthenium͑II͒ dicarbonyl. The CVD films were grown without any coreactant, while the ALD films used ammonia as a coreactant. The films are fine-grained polycrystalline ruthenium with high purity ͑Ͻ0.2% impurities͒. Ru grew as a continuous, electrically conductive, pinhole-free film on tungsten nitride ͑WN͒ films even for films as thin as 2 nm. The resistivities of the films match those of pure sputtered ruthenium of the same thickness. Roughness is Ͻ2% of the film thickness. The films are very conformal, with 80% step coverage over holes with high aspect ratios ͑40:1͒. This thermal process does not use any oxidant or plasma as a second reagent, thereby avoiding damage to sensitive substrates. The ALD growth rate can reach 1.5 Å/cycle at a substrate temperature of 300°C.

Smooth and continuous films of nickel nitride (NiN x ) with excellent step coverage were deposited from a novel nickel amidinate precursor, Ni(MeC(N t Bu)2)2, and either ammonia (NH3) or a mixture of NH3 and hydrogen (H2) gases as co-reactants. The reactants were injected together in direct-liquid-injection chemical vapor deposition (DLI-CVD) processes at substrate temperatures of 160−200 °C. Depending on the ratio of NH3 to H2 gases during deposition, the Ni:N atomic ratio in DLI-CVD NiN x films could be varied from ∼3:1 to ∼15:1, having either a cubic nickel structure or a mixture of hexagonal Ni3N and cubic Ni4N crystal structures with an incorporation of nitrogen as low as 6%. The chemical vapor deposition (CVD) growth rates of NiN x could be increased to more than 5 nm/min. The CVD films were smooth and continuous, and they had ∼100% step coverage in high-aspect-ratio (>50:1) holes. The as-deposited NiN x films had resistivities as low as ∼50 μΩ cm for film thicknesses of ∼25 nm. Annealing of the films in H2 at 160 °C or hydrogen plasma treatment at room temperature removed the nitrogen and led to pure nickel films.

Coordination of Mn(CO)3 + to a carbocyclic ring of sterically congested thiophenes activates a C−S bond to regiospecific insertion of platinum. The resulting metallathiacycles contain a nucleophilic sulfur atom that undergoes spontaneous intramolecular CO substitution at the manganese center.

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