Abstract :
The preparation of barium titanate thin
films on Ti substrates at low temperature using the
hydrothermal process was studied. In addition, the
interface relationship between film and substrate was
investigated, revealing that the Ba2+ ion diffused into
the Ti(OH)4 gel formed by Ti in a strong alkaline
solution, resulting in a homogeneous film. A 3-level
orthogonal array design was utilized to optimize the
experimental conditions. The effects of preparatory
conditions such as the barium-concentration, NaOH
concentration, reaction time and substrate surface
treatment were systematically studied. Results indicate
that the effects of the NaOH concentration and
substrate surface treatment are the significant variables
influencing the relative crystal intensity (intensity of
(110) BaTiO3 peaks in XRD spectrum/intensity of
(001) Ti peak in XRD spectrum) of the films obtained.
Polycrystalline, BaTiO3-films were obtained, with
improved crystallinity and a dielectric constant of
about 915 at 1 MHz.
