Electromodulation of wide-bandgap semiconductors
Electromodulation of wide-bandgap semiconductors
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DOI：
10.1016/j.jallcom.2018.03.004
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发表时间：
2018-05-30
影响因子：
6.2
通讯作者：
Ikram, Mujtaba
中科院分区：
文献类型：
--
作者：
Qayyum, H. A.;Al-Kuhaili, M. F.;Ikram, Mujtaba
在这项工作中，我们探索了电调制技术的功能，以确定位于紫外区的宽带隙氧化物的能隙。本文分析了Er2O3、Ga2O3、HfO2、Ta2O5和ZrO2等氧化物，并采用分光光度法和电调制法测定了它们的带隙。与需要外推才能找到材料带隙的分光光度法相反，每种氧化物的电调制光谱清楚地揭示了与材料中光学跃迁相关的临界点。考虑到分光光度法由于外推导致带隙值变化较大，以及其他带隙测定技术如电子能量损失谱、x射线光电子能谱和内部光电发射在可用性、超高真空和低信噪比等方面的潜在局限性，本研究对于考虑电调制技术作为上述实验技术的有效替代来确定宽带隙材料的能隙具有重要的价值。(C) 2018 Elsevier B.V.版权所有
In this work, we explored the functionality of the electromodulation technique to determine the energy gaps of wide band gap oxides which lie in the ultraviolet region. Oxides like Er2O3, Ga2O3, HfO2, Ta2O5 and ZrO2 were analyzed in this study with their band gaps determined through the spectrophotometric as well as with the electromodulation method. Contrary to the spectrophotometric method, where extrapolation was required to find the band gap of the material, the electromodulation spectrum of each oxide clearly revealed the critical points associated with the optical transitions in the material. Keeping in view the large variations produced by the spectrophotometric method in the band gap values due to extrapolation, and the potential limitations faced by other band gap determination techniques, like electron energy loss spectroscopy, x-ray photoelectron spectroscopy and internal photoemission, in terms of their availability, demands of ultra-high vacuum and low signal to noise ratio, this study proves to be valuable in considering the electromodulation as an efficient substitute for the above mentioned experimental techniques to determine the energy gaps of wide band gap materials. (C) 2018 Elsevier B.V. All rights reserved.