Direct Observations of Field-Intensity-Dependent Dielectric Breakdown Mechanisms in TiO2 Single Nanocrystals

Date
2020-06-16
Authors
Tian, Xinchun
Brennecka, Geoff
Tan, Xiaoli
Tan, Xiaoli
Major Professor
Advisor
Committee Member
Journal Title
Journal ISSN
Volume Title
Publisher
Altmetrics
Authors
Tan, Xiaoli
Person
Research Projects
Organizational Units
Journal Issue
Series
Department
Materials Science and Engineering
Abstract

One of the main challenges for next-generation electric power systems and electronics is to avoid premature dielectric breakdown in insulators and capacitors and to ensure reliable operations at higher electric fields and higher efficiencies. However, dielectric breakdown is a complex phenomenon and often involves many different processes simultaneously. Here we show distinctly different defect-related and intrinsic breakdown processes by studying individual, single-crystalline TiO2 nanoparticles using in situ transmission electron microscopy (TEM). As the applied electric field intensity rises, rutile-to-anatase phase transition, local amorphization/melting, and ablation are identified as the corresponding breakdown processes, the field intensity thresholds of which are found to be related to the position of the intensified field and the duration of the applied bias relative to the time of charged defects accumulation. Our observations reveal an intensity-dependent dielectric response of crystalline oxides at breakdown and suggest possible routes to suppress the initiation of premature dielectric breakdown. Hence, they will aid the design and development of next-generation robust and efficient solid dielectrics.

Comments

This document is the unedited Author’s version of a Submitted Work that was subsequently accepted for publication in ACS Nano, copyright © American Chemical Society after peer review. To access the final edited and published work see DOI: 10.1021/acsnano.0c02346. Posted with permission.

Description
Keywords
Citation
DOI
Collections