本文研究在不同條件下CO2雷射加工脆性材料Pyrex 7740和Quartz基板，並對其會產生的缺陷作探討，而為了改善一般在空氣中產生的微裂、燒焦和凸塊，提出不同厚度覆蓋層PDMS和不同水深水輔助的方式去做改善。在有覆蓋層PDMS試片加工後，Pyrex 7740和Quartz都是在低次加工，高速度可以有一無微裂和無凸塊的切割邊緣，且厚度較厚的品質較優。不同水深水輔助雷射加工Pyrex 7740和Quartz，水輔助的冷卻效應導致微裂不出現，而且水會產生對流可把熔融物帶走，對凸塊的改善可以達到更好的效果。再以模擬不同條件下所產生的溫度和熱應力解釋不同條件下微裂痕的產生，與實驗做應證。

In this study, the brittle material Pyrex 7740 and Quartz are machined using CO2 laser in the different conditions. The defects which micro-crack, bulges and scorch are produced during machining will be discussed. It is proposed that the materials are machined in different cover layer PDMS and by using water assisted in different water depth. Machining these two materials with with different thick cover layer PDMS, free-crack and free-bulge happen at low passes and high speed. The result of thicker PDMS is better. Using water assisted in different water depth, the cooling effect leads to free-crack and water makes the convection which can bring the melt debris. This method is more useful to improve the accumlation of debris. Furthermore, temperature and thermal stress simulation analysis is used to explain the formation of micro-crack and demonstrate the experiments.

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