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arXiv · 2009.01111

Scanning Transmission Electron Tomography and Electron Energy Loss Spectroscopy of Silicon Metalattices

Shih-Ying Yu·Hiu Yan Cheng·Jennifer L. Dysart·ZhaoHui Huang·Ke Wang·Thomas E. Mallouk·Vincent H. Crespi·John V. Badding·Suzanne E. Mohney
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Abstract

Transmission electron microscopy, scanning transmission electron tomography, and electron energy loss spectroscopy were used to characterize three-dimensional artificial Si nanostructures called "metalattices", focusing on Si metalattices synthesized by high-pressure confined chemical vapor deposition in 30-nm colloidal silica templates with ~7 and ~12 nm "meta-atoms" and ~2 nm "meta-bonds". The "meta-atoms" closely replicate the shape of the tetrahedral and octahedral interstitial sites of the face-entered cubic colloidal silica template. Composed of either amorphous or nanocrystalline silicon, the metalattice exhibits long-range order and interconnectivity in two-dimensional micrographs and three-dimensional reconstructions. Electron energy loss spectroscopy provides information on local electronic structure. The Si L2,3 core-loss edge is blue-shifted compared to the onset for bulk Si, with the meta-bonds displaying a larger shift (0.55 eV) than the two types of meta-atoms (0.30 and 0.17 eV). Local density of state calculations using an empirical tight binding method are in reasonable agreement.

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Shih-Ying Yu, Hiu Yan Cheng, Jennifer L. Dysart, ZhaoHui Huang, Ke Wang, Thomas E. Mallouk, Vincent H. Crespi, John V. Badding, Suzanne E. Mohney. 2020-09-02. Scanning Transmission Electron Tomography and Electron Energy Loss Spectroscopy of Silicon Metalattices. https://arxiv.org/abs/2009.01111

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