以脈衝雷射蒸鍍法成長氧化錳鋅薄膜:溫度與緩衝層之影響

Pulsed laser deposition of ZnMnO films: Effects of temperature and buffer layer

林子敬(Tzu-Ching Lin)

指導教授 ： 洪魏寬

國立臺北科技大學/電資學院/光電工程系研究所/碩士(2011年)

摘要

在本論文中，以脈衝雷射蒸鍍法於c面藍寶石基板上成長不同濃度的ZnMnO膜，探討Mn成分與ZnMnO光學性質之相依性，並研究成長溫度與緩衝層對薄膜性質之影響。
以X-ray繞射技術鑑定ZnMnO結晶相為(002)c軸取向，且隨著Mn摻雜比增加，其c軸晶格常數有增加的趨勢，並觀察到Mn於ZnO中的溶解度隨生長溫度而改變。穿透光譜量測結果顯示，ZnMnO能隙隨著Mn濃度增加而變大。其中以低溫500oC下成長之ZnMnO譜線籃移的現象最明顯，這歸因於低溫成長導致較多的Mn原子摻入。
從室溫光激螢光光譜(photoluminescence, PL)測量觀察到，Mn濃度的增加有快速抑制ZnO紫外發光之效應；在靶材中的Mn濃度增加至x=0.02時已觀測不到ZnMnO膜的發光。此外，低溫PL測量顯示Mn的摻入對氧化鋅DoX (束縛激子)的發光亦有明顯的抑制。為了提升ZnMnO的發光性質，我們進一步先於藍寶石基板上成長ZnO緩衝層，再於其上成長ZnMnO薄膜。室溫與低溫PL測量均觀察到緩衝層的設立可以有效增加發光強度。

關鍵字

脈衝雷射蒸鍍 ； 氧化錳鋅 ； 氧化鋅 ； 錳摻雜

並列摘要

In this thesis, we have studied the manganese(Mn) composition and temperature dependence of the optical propertied of ZnMnO thin film, and we have investigated the effects of buffer layer. The thin films were grown on c-Al2O3 substrates by pulsed laser deposition technique. X-ray patterns of the ZnMnO films showed them to be single phase and having wurtzite structure with (002)c-axis orientation. The c-axis lattice constant increases with increasing Mn composition and it was found that the solubility of Mn increases with decreasing temperature. The FWHM increase with Mn content increase demonstrates that Mn incorporated into ZnO leads to lattice disorder in the films.
From optical transmittance spectra, as Mn content increase, the absorption edge shifts toward higher energy side. When ZnMnO grown at 500oC， the phenomenon of blue shift was considerably obvious. It was attributed to low temperature results in more Mn incorporated. Photoluminescence(PL) measurement showed the luminescence was quenched rapidly with increasing Mn content, there are no emission peak was observed as x=0.02. Furthermore, we have investigated PL propertied of ZnMnO at 10K. The DoX emission was also quenched severely. For enhancing PL intensity, we grew ZnMnO thin films on ZnO buffer layer. PL measurement at 300oC and 10oC both showed that ZnO buffer layer can enhance the luminescence intensity.

並列關鍵字

PLD ； ZnMnO ； ZnO ； Mn-doped

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