本研究主要針對目前的玻璃雷射切割裂片製程，透過簡化熱傳方程式並考慮其有限厚度以三維點熱源之理論解推導其溫度分布在製程中的變化，並探討溫度場特性與應力大小和能否成功裂片的關連性，以期提升規畫非直線雷射路徑的效率。在應力方面，我們研究其裂片製程的主要機制及製程影響，透過各種對玻璃試片實驗的結果，我們推斷必須考量製程殘留應力的存在，並以熱影響區內設定一均勻溫升的方法來產生額外應力，使模組在模擬上更接近真實製程狀況。藉由把殘留應力的模擬方法帶入2D熱應力模型，控制其局部溫度及溫度梯度條件，計算並分析其熱應力分布。試著以單純的區域溫度參數條件計算其單點產生之最大熱應力，建立簡易熱應力計算方法。目標於提供在實際製程上已知溫度條件的狀況下可快速估算熱應力並判斷其是否達到裂片強度門檻，做為調整功率及速度等製程參數之參考，在本研究中發現不論直線或圓軌跡雷射路徑對於玻璃上下表面造成熱應力差異極大，其上表面使裂紋成長之熱應力已足夠，裂片門檻可能在於其下表面加熱溫度狀況。

In this thesis, a new method for predicting the process results of glass splitting is proposed. Specifically, for a Gaussian heat source, we calculate the transient temperature field for arbitrary laser paths. It is found that when the thickness of glass is large, the temperature on the top surface and that on the bottom surface can be substantially different, and such difference needs to be taken into account. Meanwhile, the effects of residual stress due to pre-perforation of glass using picosecond laser are examined. It was found that since the glass had been perforated by picosecond laser, there is a discoloration area surrounding each perforation where residual stress exists and reduces the strength of the glass. One collaborator of ours, Mr. Tsung-Yen Lee [1], added a fictitious temperature rise to simulate the residual stress. Moreover, another collaborator, Ms. Chiao-Fen Chuang [2], confirmed that in the local cooling process, increasing the temperature difference will improve the cutting success rate and reduce edge roughness. In the thermal stress simulation, we illustrate the difficulty of simulating thermal stress directly and put forward other alternative simulation schemes. It is found that the maximum thermal stress on the upper surface of the laser may be substantially greater than the required threshold of about 25% when the laser is heated only in the upper surface, and the bottom surface may be the threshold of the success of the glass splitting, which is only higher than that provided by our research member Tsung-Yen Lee [1]. Of the glass splitting threshold 3%, which may be consider how to heat in the thickness of the need to further use.

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