材料科学
电介质
热传导
电场
空间电荷
电子能带结构
凝聚态物理
电子
介电强度
带隙
光电子学
化学物理
复合材料
化学
物理
量子力学
作者
Zongze Li,Chao Wu,Lihua Chen,Yifei Wang,Zeynep Mutulu,Hiroaki Uehara,Jierui Zhou,Mükerrem Çakmak,Rampi Ramprasad,Yang Cao
标识
DOI:10.1002/adma.202310497
摘要
Abstract The electronic band structure, especially the defect states at the conduction band tail, dominates electron transport and electrical degradation of a dielectric material under an extremely high electric field, and the ability to probe such states provides insights into the mechanism of dielectric breakdown for better designs of new materials. However, the electronic band structure governing the charge transport in a dielectric is barely well studied due to experimental challenges in detecting the electrical conduction to an extremely high electric field, i.e., prebreakdown. In this work, we probe the electronic band structure of polymer dielectric films through a novel in‐situ prebreakdown conduction measurement method in conjunction with a space‐charge‐limited‐current spectroscopic analysis. An exponential distribution of defect states at the conduction band tail with varying trap levels is observed in accordance with the specific morphological disorder in the polymer dielectric, and the experimental defect states show also a favorable agreement with the calculated density of states from the density functional theory. The methodology demonstrated in this work bridges the molecule‐structure‐determined electronic band structure and the macro electrical conduction behavior, provides highly improved understanding of material properties that control the electrical breakdown, and paves a way for guiding the modification of existing material and the exploration of novel material for high electric field applications. This article is protected by copyright. All rights reserved
科研通智能强力驱动
Strongly Powered by AbleSci AI