高鎵摻雜氧化鋅光柵結構的表面電漿子共振行為

Surface Plasmon Resonance Behaviors of Highly Ga-doped ZnO Grating Structures

劉季武(Chi-Wu Liu)

指導教授 ： 楊志忠

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2019年)

https://doi.org/10.6342/NTU201902305

摘要

在本研究中，我們於不同厚度的高鎵摻雜氧化鋅薄膜上製作不同凹槽深度的光柵結構，光柵週期固定在1100奈米。經由此種結構的穿透以及反射頻譜量測來探討表面電漿極化子及侷域表面電漿子的共振行為。當摻鎵氧化鋅薄膜的厚度為300奈米時，只有從空氣端入射量測的反射頻譜可觀察到表面電漿極化子及侷域表面電漿子的共振行為。當摻鎵氧化鋅薄膜的厚度變薄後，從空氣端及基板端入射所量測的穿透以及反射頻譜皆可以觀察到表面電漿極化子及侷域表面電漿子共振的特徵。然而，因為分別受空氣以及藍寶石基板的影響，從空氣端及基板端入射產生的表面電漿極化子及侷域表面電漿子特徵略有不同。而當光柵結構為分隔的週期性摻鎵氧化鋅區塊，且凹槽較淺時，則不會產生表面電漿極化子及侷域表面電漿子的共振。此研究中，我們也利用數值模擬來佐證我們的實驗結果。

關鍵字

表面電漿子 ； 摻鎵氧化鋅 ； 透明導電體 ； 光柵結構

並列摘要

Based on highly Ga-doped ZnO (GaZnO) thin films of different thicknesses on sapphire substrate, grating structures of different grating ridge depths but with a fixed grating period at 1100 nm are fabricated for studying their surface plasmon polariton (SPP) and localized surface plasmon (LSP) resonance behaviors through the reflection and transmission measurements with light incident from top (air side) and bottom (sapphire side). When GaZnO thin film is thick (300 nm), the SPP and LSP features can be observed only from top through reflection measurement. When GaZnO thin film becomes thinner, the SPP and LSP features can be observed from top and bottom through either reflection or transmission measurement. However, the observed SPP and LSP features from top and bottom are slightly different due to the different effects of air and sapphire. When the grating structure consists of periodic isolated GaZnO islands, no SPP or LSP can be observed unless the ridge height is large enough for supporting LSP. Simulation studies are performed to well support the experimental data.

並列關鍵字

surface plasmon ； GaZnO ； transparent conducting oxides semiconductor ； grating structures

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