超薄化學強化玻璃因具有高強度及高硬度，廣泛被應用在智慧型行動裝置的保護玻璃上，而為了加工至指定的外型，其殘留應力導致的切割困難勢必得被克服。除了要能成功的切割裂片，切割完成後之邊緣品質也是相當重要的指標，然而傳統的CO2雷射切割裂片不但在處理化學強化玻璃上表現較差，對於切割幾何為封閉內孔的形狀也難以發揮。近年雷射長光刀切割的技術大量被開發及應用，國外大廠相繼提出相關技術，對於光路的掌握及切割國內的廠商已有一定的成果，但關鍵的內孔裂片技術仍被國外廠商所把持，對國內產業深耕此項技術有很大的阻礙。本文以改善整體切割製程為核心價值，首先希望能了解在雷射作用的高溫之下，化學強化玻璃性質的變化機制來做為熱退應力及相關技術開發、優化的參考資訊；另外，長光刀切割極具展潛力，但關鍵內孔裂片技術仍未掌握，故國內若想自主發展此極具應用價值的切割技術，則需針對其後續內孔裂片機制的探討。本研究的內容主要可以分成兩大部分，第一部分以熱處理來模擬雷射造成的高溫對化學強化玻璃加熱，再針對其做應力及一系列材料性質的檢測與綜合討論，以之為基礎探討雷射加熱來退應力後切割的可行性，以及提供雷射加工製程材料方面的理解；第二部分我們以長光刀切割封閉圓內孔做對象，提出裂片機制的發想與進行實際的測試，並在最後建立一套高邊緣品質的裂片技術。在研究成果的部分，本文成功以熱處理實現對化學強化玻璃的退應力，並發現其牽涉到複雜的材料機制變化，不僅是殘留應力，也會對其機械性質及破壞特性有很大的影響，類似的退應力製程應相當注意這一點，才能對後續的切割裂片有更好的掌握，而提高加熱的溫度能大幅縮短材料改質所需的時間，故有以雷射來進行退應力的機會；而在長光刀切割裂片製程開發的部分，本研究成功建立一套具有高品質及實用價值的熱應力裂片技術，不僅如國外廠商展示的可以成功的裂片下料，且也展示了其裂片後的邊緣品質，缺陷的最大尺寸皆壓制在15μm下，已有可立即應用至產線上的水準，此技術的開發為國內深耕長光刀切割技術做出關鍵的貢獻。

Chemically strengthened ultrathin glasses have been widely used in the display unit due to their inherent high strength for resisting possible damages. However, such an advantage also brings struggles in fabrication. In particular, cutting inner structures such as holes for camera or microphone assembly represents a challenging task for these strengthen glasses. Technically, the requirement eliminates the possibility of using traditional cutting wheels. Meanwhile, the high stresses resulted from the toughening process could easily induce uncontrollable crack propagation from flaws created during machining. Recently, fast laser ablation becomes a promising approach for handling strengthened glasses. The process can create deep micro holes array on glass. It is then possible to create controllable sub-critical crack growth from those holes for separating the glass to form hollow structures. However, such a process involves complicate pyrolytic interaction between laser and glass materials. In addition, extra auxiliary stressing processes should also be developed for achieving a reliable glass separation. In this work, the material properties of strengthen glass subjected to thermal processing are investigated for providing fundamental knowledges. Young’s modulus, hardness, residual stress, and toughness are characterized by using nano- and micro- indenters. It shows that the hardness reduced substantially once the annealing temperature exceeds 500C for 30 minutes. Furthermore, at the same processing condition, the toughness also exhibits a considerable enhancement. Finally, an auxiliary separation process based on thermal shock is proposed and realized for creating low chipping level separation. Experiments on creating circular structures are then performed with different heating and cooling conditions for demonstrating the applicability of the developed solutions. The micrographs indicated that the chipping level of the edge is less than 15m and is satisfied for the current needs.

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