SOL-GEL DERIVED BA(MG1 3TA2/3)O-3 THIN-FILMS - PREPARATION AND STRUCTURE/

Ba(Mg1/3Ta2/3)O-3 thin films were prepared by a sol-gel process involv ing the reaction of barium isopropoxide, tantalum ethoxide, and magnes ium acetate in 2-methoxyethanol and subsequently hydrolysis, spin-coat ing, and heat treatment. Transmission electron microscopy, x-ray diffr action, and Raman spectroscopy were used for the characterization of t he thin films. It was shown that the thin films tend to crystallize wi th small grains sized below 100 nm. Crystalline phase with cubic (diso rdered) perovskite structure was formed in the samples annealed at a v ery low temperature (below 500 degrees C), and well-crystallized thin films were obtained at 700 degrees C. Although disordered perovskite i s dominant in the thin films annealed below 1000 degrees C, a low volu me fraction of 1:2 ordering domains was found in the samples and grows with an increase of annealing temperature.