Negative‐U Properties of the Deep Level E3 in ZnO
Negative‐U Properties of the Deep Level E3 in ZnO
复制标题
ZnO 中深能级 E3 的负 U 性质
DOI：
10.1002/pssb.201700670
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
M. Grundmann
中科院分区：
文献类型：
--
作者：
R. Pickenhain;Matthias Schmidt;H. von Wenckstern;G. Benndorf;A. Pöppl;R. Böttcher;M. Grundmann
深能级E3是一种常见的缺陷，在体晶体和薄膜的ZnO独立的生长方法。它的化学起源仍然没有最终被理解。本文回顾了以往对E3能级的研究，并介绍了最近通过光学深能级瞬态光谱（DLTS）方法获得的实验结果，温度范围为4至350 K，光子能量为0.25至4 eV，发射速率为10−3至104 s−1。描述了E3俘获电子进入导带的光学跃迁的俘获截面。此外，第二个光学跃迁发生的光子能量高于1 eV，这说明了降低的E3 DLTS信号在低温下的照明。此外，它明确地表明，E3缺陷可以结合多达两个电子，并且它具有负U中心的性质。光致发光测量表明，E3缺陷是直接连接到一个辐射复合通道在2.09 eV。此外，电子顺磁共振（EPR）测量进行光激发依赖于温度和光子能量。有趣的是，VO+的温度依赖性EPR信号与E3缺陷的光电离截面相似。这些实验结果进行了讨论，与已发表的EPR结果和ZnO中原生点缺陷的第一性原理计算所获得的结果进行比较。
The deep level E3 is a commonly observed defect in bulk crystals and thin films of ZnO independently of the method of growth. Its chemical origin is still not finally understood. In this paper, previous research on the E3 level is reviewed and recent experimental results acquired by optical deep level transient spectroscopic (DLTS) methods are presented for the temperature range from 4 to 350 K, for photon energies between 0.25 and 4 eV, and for emission rates ranging from 10−3 to 104 s−1. The capture cross section of the optical transition of E3‐trapped electrons into the conduction band is described. Additionally, a second optical transition occurs for photon energies higher than 1 eV, which accounts for the lowering of the E3 DLTS signal at low temperatures under illumination. Further, it is unambiguously shown that the E3 defect can bind up to two electrons and that it has the properties of a negative‐U center. Photoluminescence measurements reveal that the E3 defect is directly connected to a radiative recombination channel at 2.09 eV. Further, electron paramagnetic resonance (EPR) measurements were performed with optical excitation in dependence on the temperature and photon energy. Interestingly, the temperature‐dependent EPR signal of VO+ is similar to that of the photo‐ionization cross‐section of the E3 defect. These experimental findings are discussed in comparison with published EPR results and results obtained by first‐principle calculations of native point defects in ZnO.
影响因子：
1.8
作者：
S. Lautenschlaeger;S. Eisermann;M. Hofmann;U. Roemer;M. Pinnisch;A. Laufer;B. Meyer;H. Wenckstern-H.-Wenc
通讯作者：
S. Lautenschlaeger;S. Eisermann;M. Hofmann;U. Roemer;M. Pinnisch;A. Laufer;B. Meyer;H. Wenckstern-H.-Wenc
影响因子：
3.7
作者：
Erhart, Paul;Albe, Karsten;Klein, Andreas
通讯作者：
Klein, Andreas