本文的主要目的是以二維熱傳導問題的數學模型結合雷射移動熱源建立針對雷射劈裂超薄玻璃邊緣為裂紋進行模擬與探討，以期釐清玻璃薄板溫度分佈和冷卻速率等對雷射劈裂機制的影響。透過降低玻璃邊緣為裂紋的存在，將有效提升玻璃的機械強度，未來在進行卷對卷連續製程的應用時，得以降低傳輸時造成破片的機率。
觀察雷射加熱過後的劈裂片，我們發現到除了劈裂的深度之外，還有另一個明顯的熱影響區。同時，經過實驗與理論解的計算結果指出，熱影響區深度和劈裂深度的溫度值分別為1500 K及770 K。另一方面，為了找出冷卻速率對雷射劈裂機制的影響，藉由計算超薄玻璃在劈裂過程中的冷卻速率以及與實驗結果的比較，我們發現到當超薄玻璃的冷卻速率越快，則超薄玻璃在雷射加熱之後更容易被劈裂開來。整體而言，我們可以透過一個簡單的物理模型，得以計算出溫度分佈等並可成功預測雷射劈裂後的超薄玻璃基板的劈裂位置和熱影響區位置。在未來的工程應用實務上，可以做更有效應用。而在基礎理論研究方面，也對於雷射劈裂機制的探索與了解有進一步的貢獻。

One important issue of the ultrathin glass in the R2R processing is to reduce its fragility, which is mainly caused by the ragged edge. Recently, an ingenious CO2 laser peeling technique for removing the edge defects of ultrathin glass substrates has been developed by ITRI. In order to fully understanding the fundamental mechanism of laser peeling, a theoretical model is developed to predict the temperature distribution, cooling rate, heat affected depth and peeling depth within the substrate given known values of the laser power (34 W), laser frequency (10 kHz), laser spot size (150 μm) and laser ablation pitch (50 μm). The theoretical results for the heat affected depth and peeling depth are compared with the experimental results observed by optical microscopy (OM). It is found that the theoretical results for the 1500 K envelope are in good agreement with the experimental heat affected depth, while those for the 770 K envelope are in good agreement with the peeling depth. In addition, it is found that the peeling mechanism is enhanced as the cooling rate increases. In general, the results confirm that the proposed analytical model provides a suitable tool for understanding and optimizing the laser peeling process in the R2R processing of ultrathin glass substrates.

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