HYDROTHERMAL ABO3 CERAMIC THIN-FILMS

Complex oxide thin films of ABO3 type, with one or more different cations on the A site, were prepared on B-metal substrates using the hydrothermal method: barium zirconium oxide, BaZrO3 (BZ), on Zr; barium-strontium titanium oxide, (Ba,Sr)TiO3 (BST), and barium titanium oxide, BaTiO3 (BT), on Ti. The films were prepared in the 200-250-degrees-C temperature range using a mixture of 0.5NxBa(OH)2 and (1 - x)Sr(OH)2 solutions (x = 1 for BZ and BT, and x = 0.5 for BST). XPS characterization confirmed that the A cations were incorporated into the B-metal substrate, forming a complex oxide. Dielectric breakdown occurred at 10 MV m-1 in a BST film with an estimated 20 nm thickness. In a 110 nm BZ film the dielectric breakdown was observed at 20 MV m-1. BT breaks down near 6 MV m-1 in a 100 nm film. The dielectric properties exhibit sensitivity to relative humidity.