Decomposition Behaviors of bis(N-alkoxy-b-ketoiminate) Titanium Complexes in the Depositions of TiO2 and Ba0.5Br0.5TiO3 (BST) Films

초록

Several bis(N-alkoxy-b-ketoiminate) titanium complexes have been synthesized and tested as LS-MOCVD precursors for TiO2 and Ba0.5Sr0.5TiO3 (BST) thin films. Thermal decomposition and deposition properties of these precursors were compared with those of conventional Ti precursors, such as Ti(mpd)(tmhd)2 (mpd=methylpentanedioxyl, tmhd=tetramethylheptanedionate) and Ti(tmhd)2(O-i-Pr)2. They were stable in moisture and in inert solvents, such as n-butylacetate or alcohol. We also found that the thermal stability and the volatility of these complexes were greatly dependent on the structure of functional group in the β-ketoiminato ligand. In the deposition of TiO2 films, the decomposition and deposition properties of bis(N-alkoxy-b-ketoiminate) titanium complexes were not much different with other conventional precursors. However, they were greatly harmonious with conventional Ba and Sr precursors, such as Ba(methd)2 and Sr(methd)2(methd: methoxy-ethoxy-tetramethyl-heptnedionate) in the deposition of BST films. The BST films deposited with these precursors showed very low carbon content with smooth surface morphology.