Effect of a Boron Additive on the Microstructure and Dielectric Properties of BaTiO_3 Thin Films Formed by Nanocrystal Deposition

摘要

Highly crystallized BaTiO_3 thin films were fabricated by a nanocrystal sintering process. Boron alkoxide was introduced into a slurry of Mn-doped BaTiO_3 nanocrystals with particle sizes of 5-7 nm. The deposited nanocrystal film on a (111)-oriented Pt/TiO_2/Al_2O_3 substrate was sintered at a low temperature of 800 °C and the obtained film had highly densified and oriented microstructures. We found that the boron additive enhanced the grain growth of nanoparticles and as a result the dielectric constant of the thin film increased to 1100 at 10 kHz, which is much higher than that of undoped BaTiO_3 thin films.