Publication detail

Leakage Current, Noise and Reliability of NbO and Ta Capacitors

SEDLÁKOVÁ, V. ŠIKULA, J. NAVAROVÁ, H. PAVELKA, J. HLÁVKA, J. SITA, Z.

Original Title

Leakage Current, Noise and Reliability of NbO and Ta Capacitors

Type

conference paper

Language

English

Original Abstract

An analysis of charge carrier transport and noise in NbO and Ta capacitors was performed to prove the stability, reliability and non-burning performance of NbO and Ta capacitors. VA characteristics in normal and reverse mode at room and elevated temperature have been measured to determine the mechanism of current flow and current noise sources. The charge is accumulated not only on NbO/Ta and MnO2 or conducting polymer (CP) electrodes, but also in the Nb2O5 or Ta2O5 insulating layer. Capacitance is given by a charge stored on both NbO/Ta and MnO2 electrodes and also by a charge stored on localized states in Nb2O5 or Ta2O5 insulating layers. The charge carrier transport is determined by the Ohmic, Poole-Frenkel and tunnelling mechanisms in the normal mode (for NbO/Ta electrode positive). The dispersion of leakage current values at given applied voltage is due to interface dipole layers and charge carrier transport in the insulating layer flaws and defects. The dominant mechanism in reverse mode is: (i) for low voltage (U<0.4 V) the Ohmic charge carrier transport and (ii) for higher voltage - Schottky over barrier charge carrier transport. The electron transport has stochastic component, which is analyzed by noise measurement. For low electric field intensity (E< 100MV/m) shot and g-r noise are dominant. These sources have white noise spectral density and physical processes are reversible. They correspond to high quality and reliable technology. If 1/f noise spectral density is dominant then charge carrier transport contains irreversible processes which are related to low reliability. Reliability testing method based on noise and potential barrier evaluation is proposed.

Keywords

NbO capacitor, Ta capacitor, MIS structure characteristics, Nb2O5, Ta2O5, reliability, noise

Authors

SEDLÁKOVÁ, V.; ŠIKULA, J.; NAVAROVÁ, H.; PAVELKA, J.; HLÁVKA, J.; SITA, Z.

RIV year

2007

Released

1. 1. 2007

Publisher

IMAPS Nordic

Location

Finsko

Pages from

436

Pages to

441

Pages count

6

BibTex

@inproceedings{BUT27974,
  author="Vlasta {Sedláková} and Josef {Šikula} and Hana {Navarová} and Jan {Pavelka} and Jan {Hlávka} and Zdeněk {Sita}",
  title="Leakage Current, Noise and Reliability of NbO and Ta Capacitors",
  booktitle="Proceedings EMPC 2007",
  year="2007",
  pages="436--441",
  publisher="IMAPS Nordic",
  address="Finsko"
}