Summary: | A comprehensive examination of the feasibility of producing new titania precursors by ligand substitution reactions involving the reaction between titanium tetra-isopropoxide and various dimethylamino alcohols has resulted in the synthesis, characterization and application of five new titanium dioxide thin film precursors, titanium tetra(dimethylaminopropan-l-ol) (Ti(DMAP1 )4), titanium tetra(dimethylaminopropan- 2-ol) (Ti(DMAP2)4), titanium isopropoxide tri(dimethylaminoethanol) (Ti(OPr')(DMAE)3), titanium tri-isopropoxide dimethylaminopropan-1-ol (Ti(OPr')3(DMAP')) and titanium tri-isopropoxide dimethylaminopropan-2-ol (Ti(OPri)3(DMAP2)). The new compounds have been characterized by *H and 13C NMR spectroscopy, mass spectrometry, infrared spectroscopy and thermogravimetric analysis (TGA). The precursors were tested for their ability to produce TiOa films on un-doped silicon and glass substrates by Liquid Injection Metal Organic Chemical Vapor Deposition. The effects of varying a wide range of deposition conditions has been studied using in situ monitoring by interferometry and ex-situ analysis using X-ray diffraction (XRD), scanning electron microscopy (SEM) and Rutherford back scattering (RBS). Data resulting from the use of the new precursors has been compared to that obtained using the current industry standard precursor, titanium tetra-isopropoxide (TTIP). It is demonstrated that the new precursors are potentially easier to handle than TTIP as a result of the internal coordination to the Ti centre via the N atoms in the replacement ligands, while all of the precursors studied are able to produce TiC>2 films. Comparisons are made between the precursors in terms of placing them in a rank order based upon ease of use and ability to produce TiC>2 films. Additionally, to demonstrate the applicability of these precursors, films of the mixed metal oxide strontium barium titanate have been grown and characterised.
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