Deposition of La2O3 films by direct liquid injection metallorganic chemical vapor deposition

Abstract

A novel lanthanum precursor [La(tmhd)(3)-TETEA] where tmhd is 2,2,6,6-tetramethyl-3,5-heptanedione, and TETEA is triethoxytriethyleneamine, has been characterized by thermogravimetric analysis and differential scanning calorimetry. Lanthanum oxide thin films deposited at 325-450degreesC by direct liquid injection metallorganic chemical vapor deposition process had a dense and smooth morphology. La2O3 film deposited at 325degreesC had a cubic phase with a low X-ray diffraction (XRD) intensity, while at deposition temperatures above 375degreesC, XRD patterns indicated that both hexagonal and cubic phases of La2O3 were formed. The measured capacitance of La2O3 films deposited at 350degreesC was 70 pF that gave an effective dielectric constant of 25. La2O3 film annealed at 500degreesC showed a low leakage current of 4.45x10(-8) A/cm(2) at 5 V. (C) 2002 The Electrochemical Society.