Scanning ultrafast electron microscopy: Four-dimensional imaging of materials dynamics in space and time
Scanning ultrafast electron microscopy: Four-dimensional imaging of materials dynamics in space and time
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DOI：
10.1557/mrs.2018.149
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发表时间：
2018-07
期刊：
影响因子：
5
通讯作者：
Ding-Shyue Yang;Bolin Liao;O. Mohammed
中科院分区：
文献类型：
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作者：
Ding-Shyue Yang;Bolin Liao;O. Mohammed
传统电子显微镜在过去三十年中经历了巨大的发展，特别是在设备设计和工程方面，成为材料科学和纳米技术关键研究领域最广泛认可和最强大的工具之一。在本文中，我们讨论扫描超快电子显微镜（S-UEM）作为材料表面四维电子成像的新方法。我们还举例说明了一些独特的应用。通过监测从光敏材料表面发射的二次电子，可以以足够的空间和时间分辨率对表面、界面和异质结附近的光和电子碰撞引起的电子和空穴进行成像。电荷分离、输运和各向异性运动以及它们对载流子能量的依赖性都可以得到解决。 S-UEM 准备在真实时空中直接成像和可视化新兴光电器件的相关界面动力学，并帮助提高其性能。
Conventional electron microscopy during the last three decades has experienced tremendous developments, especially in equipment design and engineering, to become one of the most widely recognized and powerful tools for key research areas in materials science and nanotechnology. In this article, we discuss scanning ultrafast electron microscopy (S-UEM) as a new methodology for four-dimensional electron imaging of material surfaces. We also illustrate a few unique applications . By monitoring secondary electrons emitted from surfaces of photoactive materials, photo- and electron-impact-induced electrons and holes near surfaces, interfaces, and heterojunctions can be imaged with adequate spatial and temporal resolution. Charge separation, transport, and anisotropic motions as well as their dependence on carrier energies can be resolved. S-UEM is poised to directly image and visualize relevant interfacial dynamics in real space and time for emerging optoelectronic devices and help push their performance.