在過去的二十年中， InGaN-GaN 量子井 (QW) 的發光二極管 LED獲得了巨大的商機，並有望最終取代白熾燈泡。然而，紫外 (UV) LED 的量子效率，特別是在 300 nm 以下的波長，仍低於 15%，阻礙了氮化物紫外 LED 的商業化。
　　在這項研究中，我們利用數值模擬的方式，分析量子井與金屬(Al)的表面電漿(surface plasmon resonance, SPR)耦合效率，目的是要設計具有更高量子效率的 UV LED 元件結構。我們發現，當Al與量子井的距離在 1 nm 的時候，量子井與Al有最強的 SPR耦合效率。為了製造UV LED元件，我們透過改變乾蝕刻時間的方式，嘗試了不同深度的p-n介面，發現當刻蝕深度為 400 nm 時，可以得到接近p-n介面的 I-V 曲線。雖然這些元件沒有產生預期的紫外光，本研究將分析元件量測的結果，也會提出解決問題的對策。

Light-emitting diode LEDs based on InGaN-GaN quantum wells (QWs) have been a huge commercial success for the past two decades, and are expected to eventually replace the incandescent light bulbs. However, the quantum efficiencies of ultraviolet (UV) LEDs, particularly at the wavelengths below 300 nm are still lower than 15 %, preventing the commercialization of nitride UV LEDs.
In this study, we employed numerical simulation to evaluate the effect of surface plasmon resonance (SPR) on nitride UV LEDs (λ = 250 nm) by varying the distance (from 0.5 nm to 6 nm) between the quantum well and the metal (Al) layer. The goal is to design the device structure of a UV LED with improved quantum efficiency. The highest SPR intensity was achieved at the separation distance of 1 nm, indicating the efficient coupling between the QW and the Al electrode. In device fabrication, we optimized the etching depth of the light-emitting mesa, and obtained the P-N junction I-V curves at the etching depth of 400 nm. Although the device did not deliver the expected UV light, detailed analyses and suggestions for future work will be provided.

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