LEAKAGE CURRENT DEGRADATION DUE TO ION DRIFT AND DIFFUSION IN TANTALUM AND NIOBIUM OXIDE CAPACITORS

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26220%2F17%3APU124678" target="_blank" >RIV/00216305:26220/17:PU124678 - isvavai.cz</a>

Result on the web

<a href="http://apps.webofknowledge.com/full_record.do?product=WOS&search_mode=GeneralSearch&qid=1&SID=V2MwdUZxCen3T8B8SCX&page=1&doc=1" target="_blank" >http://apps.webofknowledge.com/full_record.do?product=WOS&search_mode=GeneralSearch&qid=1&SID=V2MwdUZxCen3T8B8SCX&page=1&doc=1</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1515/mms-2017-0034" target="_blank" >10.1515/mms-2017-0034</a>

Result language

angličtina

Original language name

LEAKAGE CURRENT DEGRADATION DUE TO ION DRIFT AND DIFFUSION IN TANTALUM AND NIOBIUM OXIDE CAPACITORS

Original language description

High temperature and high electric field applications in tantalum and niobium capacitors are limited by the mechanism of ion migration and field crystallization in a tantalum or niobium pentoxide insulating layer. The study of leakage current (DCL) variation in time as a result of increasing temperature and electric field might provide information about the physical mechanism of degradation. The experiments were performed on tantalum and niobium oxide capacitors at temperatures of about 125 degrees C and applied voltages ranging up to rated voltages of 35 V and 16 V for tantalum and niobium oxide capacitors, respectively. Homogeneous distribution of oxygen vacancies acting as positive ions within the pentoxide layer was assumed before the experiments. DCL vs. time characteristics at a fixed temperature have several phases. At the beginning of ageing the DCL increases exponentially with time. In this period ions in the insulating layer are being moved in the electric field by drift only. Due to that the concentration of ions near the cathode increases producing a positively charged region near the cathode. The electric field near the cathode increases and the potential barrier between the cathode and insulating layer decreases which results in increasing DCL. However, redistribution of positive ions in the insulator layer leads to creation of a ion concentration gradient which results in a gradual increase of the ion diffusion current in the direction opposite to the ion drift current component. The equilibrium between the two for a given temperature and electric field results in saturation of the leakage current value. DCL vs. time characteristics are described by the exponential stretched law. We found that during the initial part of ageing an exponent n = 1 applies. That corresponds to the ion drift motion only. After long-time application of the electric field at a high temperature the DCL vs. time characteristics are described by the exponential stretched law wi

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

20201 - Electrical and electronic engineering

Project

<a href="/en/project/LO1401" target="_blank" >LO1401: Interdisciplinary Research of Wireless Technologies</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2017

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

METROL MEAS SYST

ISSN

0860-8229

e-ISSN

2300-1941

Volume of the periodical

24

Issue of the periodical within the volume

2

Country of publishing house

PL - POLAND

Number of pages

10

Pages from-to

255-264

UT code for WoS article

000404567300003

EID of the result in the Scopus database

2-s2.0-85029796619