Title: | Mixed amido/imido/guanidinato complexes of niobium: potential precursors for MOCVD of niobium nitride thin films |
Author(s): | Baunemann A; Bekermann D; Thiede TB; Parala H; Winter M; Gemel C; Fischer RA; |
Address: | "Lehrstuhl fur Anorganische Chemie II, Organometallics and Materials, Ruhr-Universtat Bochum Universitatsstr. 150, D-44780, Bochum, Germany" |
ISSN/ISBN: | 1477-9226 (Print) 1477-9226 (Linking) |
Abstract: | "Novel mixed amido/imido/guanidinato complexes of niobium are reported. The complexes were synthesized by insertion of two equivalents of di-isopropylcarbodiimide (i-Pr-cdi) or bis-cyclohexylcarbodiimide (Cy-cdi) respectively, into the niobium-amido bonds of [Nb(NR(2))(3)(N-t-Bu)] (, R = Me; , R = Et) starting out from [NbCl(3)(N-t-Bu)(py)(2)] and the respective LiNR(2) reagent (py = pyridine). Four representative examples of these mixed ligand amido/imido/guanidinato compounds were synthesized and were characterized by (1)H-NMR, (13)C-NMR, (15)N-NMR, CHN-analysis, mass spectrometry and infra-red spectroscopy. The molecular structures of [Nb(NR(2))eta(2)-(i-Pr-N)(2)C(NR(2))(2)(N-t-Bu)] (, R = Me; , R = Et) in the solid state were determined by single-crystal X-ray diffraction studies and are discussed together with the molecular structure of the starting compound [Nb(NMe(2))(3)(N-t-Bu)] (). The thermal properties of the new compounds depend on the substitution at the guanidinato ligand. Complexes of i-Pr-cdi are significantly more volatile than complexes of Cy-cdi as revealed by thermogravimetric analysis. Preliminary experiments using as a single-molecule source for metal-organic chemical vapour deposition (MOCVD) in the absence of ammonia indicate the formation of the stoichiometric, and surprisingly carbon-free, cubic niobium nitride phase" |
Notes: | "PubMed-not-MEDLINEBaunemann, Arne Bekermann, Daniela Thiede, Tobias B Parala, Harish Winter, Manuela Gemel, Christian Fischer, Roland A eng England 2008/07/11 Dalton Trans. 2008 Jul 28; (28):3715-22. doi: 10.1039/b719688a. Epub 2008 Jun 2" |