Dielectric properties of core-shell hyperbranched polyester/barium titanate nanocomposites for embedded capacitor applications

Abstract : The continuous miniaturization of electronic boards and packages requires replacing surface mounted passive devices with embedded components in printed circuit boards. Dielectric materials have to be optimized in order to improve the performances of buried passive components in terms of dielectric behavior and reliability. Barium titanate/polymer hybrid materials present a great interest as embedded capacitor materials because they combine the low-temperature processability from the polymers with the desirable dielectric properties of the barium titanate (BaTiO3) such as high dielectric constant. Furthermore, nanoparticles core/shell hybrid structure, inorganic BaTiO3 core/organic polymer shell, reduces the formation of inorganic particles aggregates. In this work, hybrid nanoparticles were synthesized by functionalizing the BaTiO3 nanopowders with hyperbranched polyesters. The resulting material, with average particle sizes of 750 nm and a BaTiO3 volume fraction of 26%, was spin-coated on a copper substrate acting as the first electrode of the capacitor. The final device was realized by covering the deposited film with a second opposite copper electrode. The thickness of the dielectric film was characterized using surface profilometry and cross-sectional optical microscopy. Dielectric properties of the hybrid material were studied with an impedance analyzer. The first results revealed that a capacitance density of 655 pF/cm² at 1 kHz can be achieved with 45 µm-thick BaTiO3/polymer films. Moreover, a dielectric constant of approximately 33 (at 1 kHz) was attained while the dielectric constant of currently available commercial embedded capacitors rarely exceeds 30. These results suggest that the BaTiO3/ hyperbranched polyesters thin-film capacitors are promising candidates to be developed as buried capacitor.
Document type :
Conference papers
Complete list of metadatas

https://hal.archives-ouvertes.fr/hal-00600614
Contributor : Isabelle Bord <>
Submitted on : Wednesday, June 15, 2011 - 11:46:40 AM
Last modification on : Thursday, January 11, 2018 - 6:21:06 AM

Identifiers

  • HAL Id : hal-00600614, version 1

Citation

Warda Benhadjala, Isabelle Bord-Majek, Matthieu Buet, Fabien Rougé, Yves Ousten. Dielectric properties of core-shell hyperbranched polyester/barium titanate nanocomposites for embedded capacitor applications. Hybrid Materials 2011, Mar 2011, France. pp.HYMA2011_0719 [B.2.1.1]. ⟨hal-00600614⟩

Share

Metrics

Record views

264