Hydrothermal growth of BaTiO3 thin films on printed circuit boards for integral capacitor applications

Polycrystalline BaTiO3 films were hydrothermally grown on Ti-coated substrates from 80 degrees C to 200 degrees C. Films grown at 200 degrees C exhibited the lowest dielectric loss of around 0.1. Proton incorporation was more severe for the 80 degrees C film resulting in higher dielectric losses and leakage currents about two orders of magnitude higher. Post deposition oxygen plasma treatment removed incorporated protons and reduced the loss tangent but did not reduce defect density. As such, the leakage current of the 80 degrees C film remained high. The films had dielectric constants of 275 to 675 from 100 Hz to 100 kHz and a value of 67 from 100 MHz to 3 GHz.