Synthesis and crystal structures of two new titanium alkoxy-diolate complexes. Potential precursors for oxide ceramics

• Published in: Journal of materials chemistry Vol. 11; no. 5; pp. 1428 - 1433
• Main Authors: JONES, Anthony C, WILLIAMS, Paul A, BICKLEY, Jamie F, STEINER, Alexander, DAVIES, Hywel O, LEEDHAM, Timothy J, AWALUDDIN, Amir, PEMBLE, Martyn E, CRITCHLOW, Gary W
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 2001
• Subjects: Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Inorganic compounds; Materials science; Metal complexes; Methods of deposition of films and coatings; film growth and epitaxy; Physics; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; Alkoxides; Inorganic compounds; Transition element complexes; Titanium complexes; Transition element compounds; Organic ligand; Oxides; XRD; Experimental study; MOCVD; Precursor; Oxide ceramics; Thin films; Titanium oxides; Organic anion; Alkoxy complex; Saturated aliphatic compound; Chemical preparation; Crystal structure
• ISSN: 0959-9428; 1364-5501
• DOI: 10.1039/b100411p

The new titanium alkoxy-diolate precursors [Ti(OCH2CH2O)(OCH2CH2NMe2)2]2 (1) and [Ti(OCMe2CMe2O)(OCH2CH2NMe2)2]2 (2) were prepared and structurally characterised by single crystal XRD. Both compounds exhibit binuclear centrosymmetric structures with bridging alkoxide groups, containing two six-coordinate Ti atoms in distorted octahedral environments. In (1) the oxygen from the ethylene glycolate ligand is involved in bridging, whereas in (2) the bridging oxygen is provided by the dimethylamino ethoxide ligand. Complexes (1) and (2) are potential precursors for Ti-containing oxides, and both have been investigated as precursors for the deposition of TiO2 thin films by liquid injection metallorganic chemical vapour deposition (MOCVD). Significantly, only complex (2) led to reproducible TiO2 deposition in the temperature range 325-450 C, whilst complex (1) exhibited a marked pre-reaction leading to highly irreproducible film growth. The difference in MOCVD behaviour between the complexes is rationalised in terms of their molecular structure. 30 refs.