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New Insights into the Role of Weak Electron?Phonon Coupling in Nanostructured ZnO Thin Films.

ABSTRACT: High-quality crystalline nanostructured ZnO thin films were grown on sapphire substrates by reactive sputtering. As-grown and post-annealed films (in air) with various grain sizes (2 to 29 nm) were investigated by scanning electron microscopy, X-ray diffraction, and Raman scattering. The electron?phonon coupling (EPC) strength, deduced from the ratio of the second- to the first-order Raman scattering intensity, diminished by reducing the ZnO grain size, which mainly relates to the Fröhlich interactions. Our finding suggests that in the spatially quantum-confined system the low polar nature leads to weak EPC. The outcome of this study is important for the development of nanoscale high-performance optoelectronic devices.

SUBMITTER: Gandhi AC

PROVIDER: S-EPMC6116313 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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New Insights into the Role of Weak Electron⁻Phonon Coupling in Nanostructured ZnO Thin Films.

Gandhi Ashish C AC Yeoh Wei-Shan WS Wu Ming-An MA Liao Ching-Hao CH Chiu Dai-Yao DY Yeh Wei-Li WL Huang Yue-Lin YL

Nanomaterials (Basel, Switzerland) 20180820 8

High-quality crystalline nanostructured ZnO thin films were grown on sapphire substrates by reactive sputtering. As-grown and post-annealed films (in air) with various grain sizes (2 to 29 nm) were investigated by scanning electron microscopy, X-ray diffraction, and Raman scattering. The electron⁻phonon coupling (EPC) strength, deduced from the ratio of the second- to the first-order Raman scattering intensity, diminished by reducing the ZnO grain size, which mainly relates to the Fröhlich inter ...[more]

PMID: 30127317

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