在量子井結構上表面奈米孔洞內膠體量子點的發光、福斯特共振能量轉換與表面電漿子耦合行為

Abstract

我們將膠體量子點和化學合成的銀奈米顆粒連同光阻填入貫穿整個量子井結構的表面奈米孔洞中，顯示量子點發光、從綠光量子點到紅光量子點之間的福斯特共振能量轉換、從量子井到量子點之間的福斯特共振能量轉換效率可以提升，而表面電漿子耦合的效果也明顯上升。在本研究中，我們首先探討在沒有量子井結構內的結果，為此我們將奈米洞的陣列製作在的氮化鎵模板上，接著，才將奈米洞的陣列製作在有銦氮化鎵/氮化鎵量子井的基板上，探討量子井與量子點之間福斯特共振能量轉換的行為。在這兩種不同的模板上，我們比較表面製作奈米洞陣列的樣品與表面為平面的樣品之結果，同時也比較兩種不同深度的奈米洞樣品，這幾種樣品，其奈米洞都貫穿量子井結構。較淺的奈米洞樣品顯示從量子井到量子點之間的整體福斯特共振能量轉換效率比較高。此外，我們也探討了比量子井更淺的奈米洞樣品，在其表面鋪上由銀奈米顆粒和量子井產生的表面電漿子耦合，來探討量子井到量子點之間的福斯特共振能量轉換之變化，結果顯示藉由表面電漿子耦合的效果可以增強福斯特共振能量轉換的效率。

The enhancements of colloidal quantum dot (QD) emission, Förster resonance energy transfer (FRET) from green-emitting QD (GQD) into red-emitting QD (RQD), FRET from embedded quantum well (QW) into QD, and surface plasmon (SP) coupling effect when QDs and synthesized Ag nanoparticles (NPs) are inserted into a surface nano-hole, which penetrates through the whole QW structure, are demonstrated. Nano-hole arrays on a GaN template to understand the effects without QW are first fabricated. Then, nano-hole arrays on an InGaN/GaN QW template for studying the FRET processes from the QW into QD are prepared. The samples with planar top surfaces for overlaying colloidal QDs are also fabricated to compare the results with the nano-hole samples. Meanwhile, the results of a set of sample with deeper nano-holes are compared with those with shallower nano-holes. The overall FRET from the QW structure into the inserted QDs in a shallower nano-hole sample is stronger. Besides, the SP coupling effect of surface Ag NPs on the FRET from the QW structure into the QDs inserted into a shallow nano-hole is investigated. The FRET process can be enhanced through the SP coupling effect.