脈衝雷射沉積之鉍鉛氧磊晶薄膜結構與其光學光催化性質之研究

Abstract

本實驗中之鉍鉛氧磊晶薄膜乃藉由脈衝雷射沉積法蒸鍍於鈣鈦礦之鈦酸鍶SrTiO3 (100)單晶基板，且在成長的過程中使用反射式高能量電子繞射即時監控樣品成長行為。鉍鉛氧磊晶薄膜之結構分析包含高解析X光繞射儀、倒晶格空間成像法以及高解析穿透式電子顯微鏡來研究薄膜晶體結構、基板磊晶關係以及應力應變與缺陷等結構性質，同時，在製程中反射式高能量電子繞射可臨場觀察樣品表面結構、形貌起伏程度以及成長模式。至於光學與光催化性質分析部分，紫外光/可見光吸收光譜儀、光柵式分光光譜儀、橢圓偏光儀以及光催化降解等分析可瞭解鉍鉛氧磊晶薄膜之光學能隙大小、折射率、介電常數與光催化效應等性質，藉由以上詳細的結構與光學性質上的量測，我們成功地研究了鉍鉛氧磊晶薄膜的晶體結構與其光學、光催化性質的關係。

The bismuth lead oxide is grown epitaxially on SrTiO3(100) single crystal substrate as thin film by means of pulsed laser deposition (PLD) equipped with reflection high-energy electron diffraction (RHEED). Structural characterizations were executed by high-resolution x-ray diffraction (HRXRD) and reciprocal space mapping (RSM) to discover both of the crystallography parameters and epitaxial relation between film and substrate. Furthermore, high-resolution transmission electron microscope (HRTEM) results show the crystallinity at atomic scale consisting with the x-ray diffraction. Meanwhile, reflection high-energy electron diffraction (RHEED) was conducted to investigate the growth process and surface structure of the bismuth lead oxide. As to physical properties, ultraviolet-visible absorption spectrum, NIR/VIS/UV micro-spot grating monochrometer, spectroscopic ellipsometry and photocatalytic performance were used to understand the optical bandgap, photocatalytic activity and optical properties. Within these comprehensive studies, we successfully analyze the structure of the bismuth lead oxide thin film and unveil the optical properties thoroughly.