以聚焦離子束製作之氧化鋅奈米薄膜之雷射特性分析

Abstract

在這篇論文中，我們成功以聚焦離子束製作出高品質的氧化鋅奈米薄膜，並研究其光學特性。為了製作出高品質的氧化鋅奈米薄膜，我們使用單晶的氧化鋅基板，並以聚焦離子束切割出長方形的氧化鋅奈米薄膜，以玻璃探針吸附薄膜並放置到鍍有介電質的矽基板上，最後再覆蓋介電質於其上，避免氧化鋅奈米薄膜產生變質與潮解。透過正向打入激發光源以及收集正向出射的螢光放光的螢光量測系統，量測樣品在不同大小的雷射光點激發下，其激發位置與放光特性的交互關係。並且量測氧化鋅激子放光頻譜，與在氧化鋅奈米薄膜中的耳語廊模態對應不同激發光點與位置的改變，最後以平面波展開法分析其光場分布與耳語廊模態階數。透過提出以聚焦離子束應用於高品質的單晶氧化鋅基板的全新製程方式，未來可製作更多樣化的氧化鋅奈米結構，並研究在不同奈米結構下的特殊放光特性。

In this thesis, we successfully demonstrate the high quality single crystalline ZnO nanomembrane fabricated by focus ion beam. To ensure the quality of the ZnO nanomembrane, single crystalline ZnO bulk is used. We use focus ion beam to make a ZnO nanomembrane and use the glass probe to move the ZnO nanomembrane from ZnO bulk to Si substrate with dielectric on it. We then cover the ZnO nanomembrane by dielectric layers to prevent ZnO from deliquesce. We use photoluminescence measurement system to measure the photoluminescence from ZnO nanomembrane with different pumping spot size and pumping positions. Both of P-band and whisper gallery mode lasing are observed. Laser action between P-band and WGM are able to be manipulated by choosing appropriate pumping condition. Plane wave expansion method is conducted to simulate field intensity distribution and the order of whisper gallery mode in the same time. We propose a new fabrication process and we expect to discuss more optical properties from different ZnO nanostructure made by focus ion beam in the future.