XPS quantification of the hetero-junction interface energy
XPS quantification of the hetero-junction interface energy
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DOI：
10.1016/j.apsusc.2012.10.112
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发表时间：
2013-01
影响因子：
6.7
通讯作者：
Zengsheng Ma;Yan Wang;Yongli Huang;Zhaofeng Zhou;Yichun Zhou;W. Zheng;Changqing Sun
中科院分区：
文献类型：
--
作者：
Zengsheng Ma;Yan Wang;Yongli Huang;Zhaofeng Zhou;Yichun Zhou;W. Zheng;Changqing Sun
我们提出了一种使用X射线光电子能谱（XPS）量化异质界面键能的方法。首先，通过对元素表面XPS核能级位移的分析，得到了孤立原子的能级和组成元素的体能级位移，作为参考;然后，测量了界面合金形成时特定能级的能量位移。从合金的光谱中减去参考光谱，我们可以计算出界面效应对结合能的影响。基于来自元素表面的能级和它们的体积位移进行校准，我们可以导出界面区域的键能、能量密度、原子内聚能和自由能。这种方法使我们能够澄清的CuPd界面的量子捕获的优势和在AgPd和BeW界面的极化的优势，作为界面能量变化的起源。所开发的方法不仅增强了XPS的功率，而且还能够在原子尺度上量化界面能，这一直是一个长期挑战的问题。
We present an approach for quantifying the heterogeneous interface bond energy using X-ray photoelectron spectroscopy (XPS). Firstly, from analyzing the XPS core-level shift of the elemental surfaces we obtained the energy levels of an isolated atom and their bulk shifts of the constituent elements for reference; then we measured the energy shifts of the specific energy levels upon interface alloy formation. Subtracting the referential spectrum from that collected from the alloy, we can distil the interface effect on the binding energy. Calibrated based on the energy levels and their bulk shifts derived from elemental surfaces, we can derive the bond energy, energy density, atomic cohesive energy, and free energy at the interface region. This approach has enabled us to clarify the dominance of quantum entrapment at CuPd interface and the dominance of polarization at AgPd and BeW interfaces, as the origin of interface energy change. Developed approach not only enhances the power of XPS but also enables the quantification of the interface energy at the atomic scale that has been an issue of long challenge.