雷射退火法是目前在LCD產業，製造低溫多晶矽薄膜最普遍的方式，本研究以脈衝式KrF雷射光照射非晶矽薄膜，使矽膜加熱、融化，然後結晶為多晶矽結構。以a-Si薄膜、二氧化矽膜及玻璃基板作為工件材料，考慮脈衝式雷射之雷射能量密度、雷射發數、脈衝覆蓋率與加入隔離層等因素，使用實驗實做製程並利用SEM觀察，來討論其對多晶矽薄膜製程之影響。脈衝雷射的瞬間功率極高，使得a-Si薄膜產生迅速地升溫並且快速地降溫。由實驗之結果可發現雷射之照射所產生之融池，若不屬於完全熔融，其平均晶粒尺寸隨著矽薄膜所獲得能量之增大而變大；若屬於完全熔融，平均晶粒尺寸反而變小，隨著雷射能量之升高，此現象愈明顯。

　　At present, the Laser annealing method is the most general way to fabricate the poly-Si film of low temperature for LCD industry. In this study, the working pieces primarily include a-Si film and glass substrate. The KrF excimer laser is used to irradiate the amorphous silicon film. The film melts and then solidifies rapidly as a poly-Si one. SEM is used to investigate the resulting poly-Si film. The control parameters of laser energy intensity, pulse number and coverage fraction are considered in this paper. The effects of these control parameters on the average grain size of poly-Si have been studied. The effect of SiO2 layer put between Si film and glass substrate was also investigated. From the experimental results, it can be found that if the molten pool of Si caused by laser energy doesn’t belong to “complete melt”, the more energy obtained from the laser could lead to the larger average grain size. However, if it belongs to “complete melt”, the average grain size would be much smaller than that of the former one (non-complete melt). With the increase of laser energy, the phenomenon becomes more significant.

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