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光学技术在电子显微镜中对单个纳米结构的综合表征
Incorporating optical techniques in electron microscopy for comprehensive characterization of individual nanostructures |
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| 课程网址: |
http://videolectures.net/kolokviji_gao_iot/
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| 主讲教师: |
Min Gao
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| 开课单位: |
北京大学
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| 开课时间: |
2008-12-03
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| 课程语种: |
英语
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| 中文简介: |
本次非正式演讲的目的是简要介绍北京大学研究小组的一些新内容, 并寻求今后与 jsi 的更多合作。 光学技术 (如发光和拉曼光谱) 可以提供丰富的半导体特性 (带状结构、声子结构、限制等) 信息, 这些信息是电子显微镜技术的补充。初步努力将亚微米光学技术与电子显微镜中的原位纳米探针技术结合起来, 对单个半导体纳米结构进行综合表征。 在第一种方法中, 我们将单个悬浮半导体纳米线或纳米线附加到纳米尺寸的金属尖端上, 这些尖端与不同的仪器兼容, 如扫描电子显微镜 (sem)、透射电子显微镜 (tem) 和微光致发光 (pl)。因此, 在相同的1D 纳米结构下, 可以对 sem 内的光学 (pl)、微观结构 (sem 和 tem) 和电 (纳米探针) 技术进行表征。我们对原位退火 zno 纳米线的研究结果表明, 缺陷 相关的绿色发射、近带边缘发射的红移、载流子密度和缺氧之间存在决定性的相关性。这种高度灵活的技术还可以对单个悬浮氧化锌纳米棒进行角度依赖性微光发光测量。在第二种方法中, 我们将光纤探针与 sem 中的纳米探针技术结合起来, 实现了单腔内光电子纳米结构的综合表征。 纳米探针技术采用尖锐的金属尖端, 用于纳米结构操作和电气测量。 光纤探针与光谱仪或激光耦合, 由纳米机械手控制, 允许局部光学检测或激发。利用基于单个纳米结构的原位光发射器和光电探测器, 证明了上述技术具有较高的灵活性和效率, 可在建立光电器件样机和选择合适的领域发挥重要作用。用于器件目的的纳米结构。----
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| 课程简介: |
The purpose of this informal talk is to introduce briefly some new additions to the research group at Peking University and seek more future collaborations with JSI. Optical techniques (e.g., luminescence and Raman spectroscopy) can provide rich information on semiconductor properties (band structure, phonon structure, confinements, etc.), which are complementary to electron microscopy techniques. Initial efforts have been carried out to combine submicron optical techniques and in situ nanoprobe technique in electron microscopy to carry out comprehensive characterization of individual semiconductor nanostructures. In the first approach, we attach individual suspended semiconductor nanowires or nanorods to nanometer sized metal tips, which are compatible for different instruments, such as scanning electron microscope (SEM), transmission electron microscope (TEM) and microphotoluminescence (PL). Thus optical (PL), microstructural (SEM and TEM) and electrical (nanoprobe technique inside SEM) characterization can be carried out on the same 1D nanostructure. Our results on in situ annealed ZnO nanowires show conclusive correlations among defectrelated green emission, redshift of the near band edge emission, carrier density and oxygen deficiency. This highly flexible technique also enables angular dependent microphotoluminescence measurements on individual suspended ZnO nanorods. In the second approach, we combine optical fiber probe with the nanoprobe technique in SEM to achieve comprehensive characterization of optoelectronic nanotructures inside a single chamber. The nanoprobe technique, employing sharp metal tips, is used for nanostructure manipulation and electrical measurement. The fiber probe, coupled to a spectrometer or a laser and controlled by a nanomanipulator, allows local optical detection or excitation. Using in situ light emitter and photodetector based on individual nanostructures, we demonstrate that above technique with high flexibility and efficiency can play an important role in building prototype optoelectronic devices and selectingsuitable nanostructures for device purposes. ----
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| 关 键 词: |
技术; 纳米技术; 光电子器件
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| 课程来源: |
视频讲座网
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| 最后编审: |
2020-07-06：heyf
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| 阅读次数: |
57
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