分層熱退火對氧化鋅成長之研究

Crystallinity Improvement of ZnO Thin Film by Hierarchical Thermal Annealing

周柏慶(Po-ching Chou)

指導教授 ： 王祥辰

國立中正大學/工學院/光機電整合工程研究所/碩士(2012年)

摘要

本論文中，我們使用分子束磊晶技術(MBE)來成長氧化鋅薄膜在藍寶石基板上，並透過氧化鎂緩衝層以及兩段式成長，來提升氧化鋅薄膜磊晶品質。熱退火不同層對於氧化鋅薄膜的光學、結晶特性、應力表現與表面型態等影響為主要探討的方向。從XRD量測中可以得到較小的繞射峰半高寬(FWHM=71.65 arcsec ,熱退火氧化鎂緩衝層),108.68(無熱退火試片)arcsec，顯示熱退火越底層對於氧化鋅薄膜的結晶品質越能有效提升。XRD的量測中也得知，退火越底層對於應力的釋放越是有效，其中熱退火氧化鎂緩衝層與單純熱退火HT-ZnO的試片相比應變量下降了26%，與無熱退火的樣品相比應變量下降了33%。本實驗中熱退火氧化鎂的AFM RMS為0.255nm與熱退火HT-ZnO相比下降了80%。從PL的量測也得到熱退火氧化鎂因為結晶品質上升使得其近帶隙放光有最高的強度。綜合以上結果可以得知熱退火越底層對於應力的累積越能有效的控制，並得到高品質的氧化鋅薄膜。

關鍵字

氧化鋅 ； 退火

並列摘要

In this study, we epitaxial growth of ZnO thin films with MgO buffer layer were grown on (0001) c-sapphire by molecular beam epitaxy (MBE). The effect of HT-ZnO prepared on optical, crystal and morphological properties by Hierarchical Thermal Annealing in different layer is reported.
From XRD measurements, the narrowing of (002) diffraction peak (FWHM=71.65 arcsec, thermal annealing the MgO buffer layer) and (FWHM =108.68 arcsec, non-thermal annealing) shows the annealing MgO can improve the crystal quality effectively. Annealing the bottom layer is more effective for relase the stress, in which compared the annealing MgO buffer layer and only annealing the HT-ZnO, the strain decreased by 26%. In order to compare the non-thermal annealing sample that strain is decreased by 33%. The optimum AFM RMS is 0.255nm with annealing MgO buffer layer compared with annealing HT-ZnO decreased by 80%. Annealing the MgO buffer layer has the highest edge band emission is due to crystal quality enheacement by photoluminescence (PL) measurement.
From above results, it was found that annealing the bottom layer can control stress accumulation more effectively for high-quality ZnO thin film growth.

並列關鍵字

ZnO ； Annealing

參考文獻

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