準分子雷射常用於重熔矽膜，以製備低溫多晶矽，製程參數的設定，大都是以實驗方式得到。由於電腦科技的進步，模擬鑄件的凝固已被用工業廣為採用。本論文主要目的是以ProCAST模擬矽膜的重熔與凝固，並利用長晶模組CAFE研究矽膜凝固的成核與晶粒成長的機制。研究過程包括建立矽膜熱傳模型，物理性質的評估，以及分析雷射能量及長晶成核密度對矽膜溫度的影響。結果顯示：(1) 矽膜熔化後維持為液態時間受到雷射能量、界面熱阻及底層溫度的影響；(2)矽膜凝固的主要核凝機制是面成核，面成核的密度及位置將會影響晶粒的大小及形態。

Excimer lasers have been used to re-melt silicon film to fabricate low temperature poly-silicon (LTPS); it needs to conduct experiments to settle the processing parameters. The advanced computer technologies have been used to simulate the solidification of castings by foundry industries. In this research it is aimed to use ProCAST to simulate the re-melting and solidification of silicon film, CAFE is also used to study the nucleation and growth mechanisms of silicon film solidification. This study has included the construction of models, data reviewing, and analyzing the effect of energy intensity and nuclei density on the temperature of the silicon film. The results show that: (1) The silicon melting duration time is affected by the laser intensity, interfacial thermal resistance and the temperature of sub-layer; (2) Surface nucleation is the controlling mechanism in the solidification, the nuclei density and locations of the surface nucleation will affect the size and morphology of the solidified grains in the silicon film.

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