Preparation of polyimide/BaTiO3‐nanocrystal hybrid thin films and their dielectric property

High dielectric constant is highly desirable in capacitors and memory devices. In this work, oleic acid (OA)‐capped BaTiO₃ nanocrystals were synthesized by a two‐phase approach. Polyimide (PI)/BaTiO₃‐nanocrystal composite thin films with high dielectric constant have been successfully fabricated. The morphologies and dielectric properties of the hybrid films were exploited. The results showed that BaTiO₃ nanocrystals can be uniformly dispersed in the PI thin films owing to the surface modification of OA‐capped BaTiO₃ nanocrystals. It was found that the dielectric constant of composite film varies with the volume fraction of BaTiO₃ nanocrystals and sintering temperatures and reaches a maximum value of 44.1, which is around 13 times higher than that of pristine PI thin film (3.2). These results demonstrated that PI/BaTiO₃‐nanocrystal composite films have considerable application potential in microelectronic fields.