Preparation And Characterization Of Polyamide/Nanocrystals Hybrid Films With High Dielectric Constant

High-performance polyimide (PI) films and coating materials are widely applied in microelectronic industries owing to their outstanding mechanical strength, excellent chemical resistance, and reliable stability. However, with the continuous development of the high technology, pristine PI thin films can not meet the requirements of the high technical products. So researchers continue to improve the performances of PI thin films by optimizing the process of preparation and modificating the thin films by incorporating nano-inorganic particles. Nevertheless, the former with a long period, huge-investment and have a high requirement to the equipment. The latter has the characteristics of low cost, effective and have become a main way of preparating excellent properties PI thin films.In this paper, oleic acid-capped ZrO2 nanocrystals, BaTiO3 nanocrystals were synthesized by a two phase approach, and La(OH)3 nanocrystals were synthesized by a hydrothermal approach. And ZrO2 nanocrystals and BaTiO3 nanocrystals were modified before graft with polyamic acid. We fabricated PI/ZrO2-nanocrystals hybrid thin films, PI/BaTiO3-nanocrystals hybrid thin films, PI/La(OH)3-nanocrystals hybrid thin films. Afterwards, The nanocrystals and organic/inorganic hybrid thin film was characterized by TEM, XRD, step tester, SEM, LCR meter, and FTIR. Our experimental results confirmed that nanocrystals were well dispersed and embedded in the hybrid thin films. And we fabricated polyimide/ZrO2-nanocrystals hybrid thin films with dielectric constant of 6.1, polyimide/BaTi03-nanocrystals hybrid thin films with dielectric constant of 44, polyimide/La(OH)3-nanocrystals hybrid thin films with dielectric constant of 4.6. Compared with pure polyimide thin film, the dielectric constant of polyimide/nanocrystals hybrid thin films significantly increased due to the incorporation of inorganic component.