Tetrakis(dimethylamino)titanium (TDMAT), also known as Titanium(IV) dimethylamide, is a chemical compound. The compound is generally classified as a metalorganic species, meaning that its properties are strongly influenced by the organic ligands but the compound lacks metal-carbon bonds. It is used in chemical vapor deposition to prepare titanium nitride (TiN) surfaces and in atomic layer deposition as a titanium dioxide precursor. The prefix "tetrakis" refers the presence of four of the same ligand, in this case dimethylamides.
Tetrakis(dimethylamino)titanium is a conventional Ti(IV) compound in the sense that it is tetrahedral and diamagnetic. Unlike the many alkoxides, the diorganoamides of titanium are monomeric and thus at least somewhat volatile. It is prepared from titanium tetrachloride (which is also tetrahedral, diamagnetic, and volatile) by treatment with lithium dimethylamide:[1]
TiCl4 + 4 LiNMe2 → Ti(NMe2)4 + 4 LiClLike many amido complexes, TDMAT is quite sensitive toward water, and its handling requires air-free techniques. The ultimate products of its hydrolysis is titanium dioxide and dimethylamine:
Ti(NMe2)4 + 2 H2O → TiO2 + 4 HNMe2In a related reaction, the compound undergoes exchange with other amines, evolving dimethylamine.
TMAT has been used in metalorganic chemical vapor deposition (MOCVD).