本研究使用波長為248 nm 的KrF準分子雷射退火，針對薄膜電晶體之主動層氧化銦鎵鋅的氧空缺含量進行調整，藉由脈衝雷射提供的能量提升薄膜內氧空缺數量，進而達到提升載子移動率之目的。
在本論文中，我們主要探討改變準分子雷射的能量密度與雷射製程步驟之順序對薄膜電晶體特性的影響，設定之雷射能量密度為100 mJ/cm2~400 mJ/cm2，探討雷射退火處理於源/汲極電極沉積前後對於元件特性之影響。我們以氮化鉭作為金屬閘極材料，搭配氧化矽鉿作為閘極介電層來製作氧化銦鎵鋅薄膜電晶體。物性分析方面我們利用X 光繞射分析(XRD)與化學分析電子儀(XPS)，分析氧化銦鎵鋅薄膜於不同雷射能量密度下，其晶格與內部化學鍵結之變化，結果顯示在本研究所設定之雷射能量密度區間內，氧化銦鎵鋅薄膜無明顯結晶，而其薄膜內氧空缺含量則隨著能量密度提升而增加，並在300 mJ/cm2達到高峰。於元件電性比較上，在源/汲極電極沉積後施以雷射能量密度為300 mJ/cm2處理之元件特性表現最好。電晶體之特性量測包括IDS-VDS和IDS-VGS 特性，實驗結果顯示電晶體之開關電流比約為105，另由IDS-VGS萃取出臨界電壓約為0.14 V，次臨界擺幅為92 mV/decade，而通道中的載子遷移率則由未施以雷射退火處理之12.36 cm2V-1s-1提升至17.79 cm2V-1s-1。
由實驗結果顯示，以KrF準分子雷射退火針對氧化銦鎵鋅薄膜電晶體進行加工處理，適用於提升電晶體之載子移動率，對於未來顯示技術(AMLCD或AMOLED) 與軟性電子的應用深具潛力◦

This study utilizes excimer laser annealing focusing on adjusting the oxygen vacancies of IGZO layer to improve TFTs’active layer. In this thesis, IGZO TFTs with Tantalum nitride (TaN) gate electrode and hafnium silicon oxide (HfSiO) gate insulator were fabricated and characterized. The effect of laser energy density and sequence being applied in the process on TFTs’ characteristics was mainly investigated. The energy density is set between 100 mJ/cm2 to 400 mJ/cm2, and the two forms of deposition processing were performed, which were as following: Condition B- Laser annealing before S/D metal contacts deposition and Condition C- Laser annealing after S/D metal contacts deposition. The physical properties and compositions of IGZO films were examined by XRD and XPS analysis. When comparing the element characteristics, the combination of the energy density of 300mJ/cm2 and condition C had the most satisfying performance characteristics after laser processing. The Ion/Ioff ratio, threshold voltage, subthreshold swing, and mobility obtained from the fabricated IGZO-TFTs were 105, 0.16V, 0.08V/dec, and 17.79cm2V-1s-1, respectively.
In summary, our experimental results revealed that excimer laser annealing processing on IGZO thin-film-transistors (TFTs) is perfect for enhancing carrier mobility and has great potential for future commercial TFT LCD and flexible electronics.

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