利用不同方式成長之氧化鋅晶種層所製備
氧化鋅奈米柱之特性分析

本論文研究於(111)面矽基板上先分別以浸塗與旋塗方式之溶膠凝膠(Sol-gel)法中製備晶種層，然後再利用水熱合成法成長出高均向性之一維氧化鋅奈米柱陣列，對於不同方式所製備晶種層之影響有所探討。溶膠溶液係將50ml乙醇加入數克醋酸鋅(Zn(CH3COO)2‧H2O)攪拌使部分溶解後再滴入與醋酸鋅等莫耳之單乙醇胺(C2H7NO, MEA)，以60℃攪拌1小時後配製而成。至於合成氧化鋅奈米柱所使用之化學溶液則是先量取所需之醋酸鋅與四氮六甲環(C6H12N4, HMT)數克，各加入50ml之純水，然後將兩溶液震洗3分鐘使溶質完全溶解，再把醋酸鋅溶液加入HMT溶液後配製而成。最後奈米柱是在85℃下加熱3小時製備。我們探討旋塗次數、溶膠濃度以及成長奈米柱溶液濃度等因素對於所成長氧化鋅奈米柱陣列表面型態與發光特性之影響。於氧化鋅奈米柱品質分析方面，分別以X光繞射儀(XRD)與掃描式電子顯微鏡(SEM)來鑑別氧化鋅晶體結構與表面型態，進而以光激螢光光譜(PL)來了解其紫外光特性光與缺陷所致可見光發光情形。結果顯示，PL發光機制在室溫下主要是經由free exciton主導，低溫下則為bound exciton主導，且經由實驗結果分析得知改變晶種層參數對氧化鋅奈米柱成長有所影響；對於晶種層之影響，以旋塗法來製備晶種層可獲得較均勻的成核現象，而改變晶種層溶液濃度與改變塗佈次數亦會影響晶種層晶粒大小及密度，如塗佈次數較多或晶種層溶液濃度增大，可得到口徑較小之奈米柱。就同一種晶種層上以不同溶液濃度所成長之奈米柱則隨著溶液濃度的增加奈米柱口徑與高度亦隨之增加。

關鍵字

X光繞射儀(XRD) ；掃描式電子顯微鏡(SEM) ；光激螢光光譜(PL)

並列摘要

This study is aimed at sol-gel method on silicon substrates, respectively use dip coating and spin coating methods to grow the seed layer，then the aqueous solution were synthesized with high aligned one-dimensional zinc oxide nanorods array。 In this experiment，zinc acetate(Zn (CH3COO) 2‧H2O)as a solute and ethanol(C2H5OH)as the solvent，the mix solution(monoethanolamine : Zn (CH3COO)2=1:1) was added dropwise to the solution，stirred at 60 ℃ 1 hours to get the uniform and transparent solution，and use spin coating method and dip coating method respectively，we also change the solution at different concentrations， numbers of the seed layer。Then，we use the mixed solution of zinc acetate and HMT which the ratio of the zinc acetate(Zn (CH3COO) 2‧H2O)and hexamethylenetetramine(C6H12N4)was 1 to grow the zinc oxide nanorods。We fixed the reaction time for three hours and growth temperature to 85 ℃， also with different solution concentrations。Tuning the different methods to get the seed layer and other fabrication parameters to synthesize the zinc oxide nanorods are used to investigate the zinc oxide nanorods of the crystalline quality，surface morphology and luminescence properties。 The crystal structure and growth orientation of the ZnO nanorods were characterized by X-Ray diffraction and SEM analysis, respectively. The various of aspect ratio and density of ZnO nanorods were obtained with different reactant concentration and growth time. Photoluminescence spectra results of ZnO nanorods reveal strong UV and visible emission. The ratio of UV and visible light were increased as the reactants concentration increased.