Publication detail

Nanostructured anodic-alumina-based dielectrics for high-frequency integral capacitors

MOZALEV, A. SAKAIRI, M. TAKAHASHI, H. HABAZAKI, H. HUBALEK, J.

Original Title

Nanostructured anodic-alumina-based dielectrics for high-frequency integral capacitors

Type

journal article - other

Language

English

Original Abstract

Three types of thin solid films with the nanoscale inner structures were synthesized by sputtering-deposition and anodizing of Al layer, Al-Si alloy layer, and Al/Ta bilayer on Si wafers. All the anodic films comprised nanoporous alumina layer as the key component. The essential differences were due to the silicon impurities (AlSi alloy) and the array of nanosized tantalum oxide protrusions in the alumina barrier layer (Al/Ta bilayer). The films were examined by scanning and transmission electron microscopy and electrochemical impedance spectroscopy. Integral capacitors utilizing the anodic films as dielectrics combine the small-value capacitance (6.5 nF cm-2) with the excellent properties of high withstand field strength, low leakage current, and low loss tangent. The revealed dispersion of dielectric constant, and the presence of loss peaks on the temperature and frequency dependencies of losses denote the influence of ion-relaxation mechanism on dielectrics polarizability, with the characteristic times depending on the dielectric type. By selecting appropriate technological and electrolytic conditions, the functionality of the capacitors can be optimized to meet the needs of a specific range, from 1 kHz to about 300 MHz operating frequencies.

Keywords

porous alumina; tantalum oxide; nanostructure; dielectric properties; electric polarization; integral capacitors; high-frequency performance

Authors

MOZALEV, A.; SAKAIRI, M.; TAKAHASHI, H.; HABAZAKI, H.; HUBALEK, J.

RIV year

2012

Released

28. 2. 2012

Publisher

ELSEVIER SCIENCE SA

Location

PO BOX 564, 1001 LAUSANNE, SWITZERLAND

ISBN

0040-6090

Periodical

Thin Solid Films

Year of study

-

Number

-

State

Kingdom of the Netherlands

Pages from

1

Pages to

9

Pages count

9

URL

http://www.sciencedirect.com/science/article/pii/S0040609012002295#

BibTex

@article{BUT96730,
  author="Alexander {Mozalev} and Masatoshi {Sakairi} and Hideaki {Takahashi} and Hiroki {Habazaki} and Jaromír {Hubálek}",
  title="Nanostructured anodic-alumina-based dielectrics for high-frequency integral capacitors",
  journal="Thin Solid Films",
  year="2012",
  volume="-",
  number="-",
  pages="1--9",
  issn="0040-6090",
  url="http://www.sciencedirect.com/science/article/pii/S0040609012002295#"
}