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Title: On the nature of high field charge transport in reinforced silicone dielectrics: Experiment and simulation

Abstract

The high field charge injection and transport properties in reinforced silicone dielectrics were investigated by measuring the time-dependent space charge distribution and the current under dc conditions up to the breakdown field and were compared with the properties of other dielectric polymers. It is argued that the energy and spatial distribution of localized electronic states are crucial in determining these properties for polymer dielectrics. Tunneling to localized states likely dominates the charge injection process. A transient transport regime arises due to the relaxation of charge carriers into deep traps at the energy band tails and is successfully verified by a Monte Carlo simulation using the multiple-hopping model. The charge carrier mobility is found to be highly heterogeneous due to the non-uniform trapping. The slow moving electron packet exhibits a negative field dependent drift velocity possibly due to the spatial disorder of traps.

Authors:
;  [1]
  1. Department of Material Science and Engineering, Rensselaer Polytechnic Institute, 110 8th street, Troy, New York 12180 (United States)
Publication Date:
OSTI Identifier:
22597740
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 5; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CARRIER MOBILITY; CHARGE CARRIERS; CHARGE DISTRIBUTION; CHARGE TRANSPORT; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; DIELECTRIC MATERIALS; ELECTRONS; INJECTION; MONTE CARLO METHOD; SILICONES; SPACE CHARGE; SPATIAL DISTRIBUTION; TIME DEPENDENCE; TUNNEL EFFECT; VELOCITY

Citation Formats

Huang, Yanhui, E-mail: huangy12@rpi.edu, and Schadler, Linda S.. On the nature of high field charge transport in reinforced silicone dielectrics: Experiment and simulation. United States: N. p., 2016. Web. doi:10.1063/1.4945373.
Huang, Yanhui, E-mail: huangy12@rpi.edu, & Schadler, Linda S.. On the nature of high field charge transport in reinforced silicone dielectrics: Experiment and simulation. United States. doi:10.1063/1.4945373.
Huang, Yanhui, E-mail: huangy12@rpi.edu, and Schadler, Linda S.. 2016. "On the nature of high field charge transport in reinforced silicone dielectrics: Experiment and simulation". United States. doi:10.1063/1.4945373.
@article{osti_22597740,
title = {On the nature of high field charge transport in reinforced silicone dielectrics: Experiment and simulation},
author = {Huang, Yanhui, E-mail: huangy12@rpi.edu and Schadler, Linda S.},
abstractNote = {The high field charge injection and transport properties in reinforced silicone dielectrics were investigated by measuring the time-dependent space charge distribution and the current under dc conditions up to the breakdown field and were compared with the properties of other dielectric polymers. It is argued that the energy and spatial distribution of localized electronic states are crucial in determining these properties for polymer dielectrics. Tunneling to localized states likely dominates the charge injection process. A transient transport regime arises due to the relaxation of charge carriers into deep traps at the energy band tails and is successfully verified by a Monte Carlo simulation using the multiple-hopping model. The charge carrier mobility is found to be highly heterogeneous due to the non-uniform trapping. The slow moving electron packet exhibits a negative field dependent drift velocity possibly due to the spatial disorder of traps.},
doi = {10.1063/1.4945373},
journal = {Journal of Applied Physics},
number = 5,
volume = 120,
place = {United States},
year = 2016,
month = 8
}
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