利用區域化表面電漿子共振加強柱狀氧化鋅之放光

Localized Surface Plasmon Enhanced Green-Yellow Light Emission of the ZnO Nanorod Arrays Using Metal Island Film

林晉安(Chin-An Lin)

指導教授 ： 何志浩

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2008年)

https://doi.org/10.6342/NTU.2008.10668

摘要

在本論文中，我們利用水熱法於金跟銀上合成出高指向性的柱狀氧化鋅。 在第一部分，我們觀察成長於鍍金矽基板上的柱狀氧化鋅。我們發現到金膜上金顆粒有助於氧化鋅的成長。在X光繞射部分，我們發現到此柱狀氧化鋅結構對於(103)面有高指向性。 透過區域化表面電漿共振的效果，成功的提高了柱狀氧化鋅在缺陷部份的放光。 透過金的幫助下，在光激螢光我們觀察到可能光/紫外光的放光比有將近107倍的加強。可見發光的波峰部分，可以觀察到逐漸由570 nm 紅移到 600nm，這是由於金的區域化表面共振散射長波長共振帶所導致的結果。而在陰極電子激螢光部分，也顯示出與光激螢光相同的結果。
第二部分，我們同樣地利用水熱法在鍍銀的矽基板上成長高指向性柱狀氧化鋅。掃描式電子顯微鏡觀察到銀的膜厚與金屬顆粒有正比趨勢。在X光繞射譜，我們發現此柱狀氧化鋅對於(002)面有高指向性。透過光激螢光的分析，銀對於缺陷放光的則加強在波長500nm附近。透過以上分析，我們證實了區域化表面電漿共振與金屬的顆粒大小有很大的相依性，並且根據金屬的顆粒及種類，會分別加強不同波長的放光。 而發光的強度與金屬膜厚的趨勢則是正相關。

關鍵字

氧化鋅 ； 奈米柱 ； 光激螢光 ； 陰極電子激螢光 ； 區域化表面電漿共振

並列摘要

In this thesis, we synthesized the high orientation ZnO nanorods array by hydrothermal process. First, we studied the ZnO on the Au-coated Si substrate. The diameter of ZnO arrays could be controlled with the aid of Au island films as a catalyst. The X-ray diffraction investigation indicated that the epitaxy of the ZnO array preferred to grow along the plane (103). Defect-level emission was greatly enhanced due the localized surface plasmon resonance of Au island film coupled with ZnO array. The intensity ratio of visible/UV was enhanced 107 times with the aid of Au island films. The enhanced DLE redshift from 570 to 600 nm confirms that the PL enhancement arises mostly from the effective scattering of the LSP in the longer wavelength range of in-plane resonance band.
Second, we demonstrate that vertical well-aligned crystalline ZnO nanorods arrays were grown on Ag/Si substrates by hydrothermal process. Different thicknesses of Ag films on Si substrates were prepared by e-gun evaporator. The morphology of Ag films were observed by the scanning electron microscopy. The XRD of ZnO on Ag islands result indicated that the epitaxy will grow along the plane (002). The Ag films have help for the enhancement of the emission at around 500nm. We prove that the LSP resonance depends on the size of the metal and the LSP resonance only happens at specific wavelength. The effect of the LSP varies with both the intensity and wavelength of DLE.

並列關鍵字

ZnO ； nanorods ； Photoluminescence (PL) ； cathodoluminescence (CL) ； Localized Surface Plasmon Resonance (LSPR)

參考文獻

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