| Abstract
| - A mixture of the tungsten allylimido complexes Cl4(RCN)W(NC3H5) (3a, R = CH3 and 3b, R =Ph) was tested as a single-source precursor for growth of tungsten nitride (WNx) or carbonitride (WNxCy)thin films. Films deposited from 3a,b below 550 °C contained amorphous β-WNxCy, while those depositedat higher temperatures were polycrystalline. Film growth rates from 3a,b ranged from 5 to 10 Å/min overa temperature range of 450−650 °C, and the apparent activation energy for film growth was 0.15 eV. Aplot of the Ea values for deposition from Cl4(RCN)W(NR‘) [R‘ = Ph, iPr, allyl] against the N−C imido bondstrengths for the analogous amines R‘NH2 is linear, implicating cleavage of the N−C bond as the rate-determining step in film growth. The correlation of mass spectral fragmentation patterns for Cl4(RCN)W(NR‘) with film properties such as nitrogen content supports the significance of facile N−C bond cleavagein film growth.
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