鉭酸鋰晶圓(Lithium Tantalate, LT)於材料上具有獨特優異的焦電(Pyroelectric)、壓電(Piezoelectricity)和電光(Electro-optic)等特性，此材料具有良好的機械和化學穩定性，第五代通訊行動技術(5G)之高射頻元件、無線通訊頻段等高頻濾波元件市場規模快速成長，因目前產線以游離磨料切片為主，造成環境汙染與切片後漿料無法有效回收。故本研究添加乙二胺四乙酸(EDTA)於冷卻液中輔助複線式鑽石切片製程，藉由乙二胺四乙酸反應溶液使鉭酸鋰材料表面產生反應，利用拉曼元素和維克氏硬度等驗證鍵結反應型態，以及推算比切削能，進行參數之設置。本研究先行利用單線式線鋸切割機(SWSM)，以此機台驗證鉭酸鋰表面產生化學反應之效率，由結果可以得知，透過乙二胺四乙酸(EDTA)加氫氧化鈉(NaOH)輔助線鋸製程可以有效改善鉭酸鋰表面之粗糙度Sa約為39.1%、Ra約為38.8%、Rz約為33.2%，微量式輔助反應溶液也有效改善約為Sa約為9.2%、Ra約為12.4%、Rz約為10.6%，並且於電子顯微鏡觀察到加入反應溶液之切屑為長條狀，藉由反應溶液輔助機制使得脆性破壞轉變成延性破壞，然後應用實際複線切片機台DWS-150進行結果比較，加入反應溶液之材料移除率增加10.7%左右，以及有效改善晶圓非均勻度(N.U.)約42.6%左右，也成功減少次表層深度約12.1%，本研究結果可以應用於鉭酸鋰切片製程量產製程配方。

Lithium Tantalate (LT) has unique properties such as pyroelectric, piezoelectricity and Electro-optic, therefore has good mechanical and chemical stability. The market of high-frequency filter components, fifth-generation(5G) communication mobile technology, high-frequency components, and wireless communication frequency bands have strong demands. The current production line is mainly based on free abrasive slicing which is not environment friendly and slurry cannot be recycled easily. Thus, this study aims to develop a compound coolant to improve LT wafer’s surface topography by multi-wire diamond wire slicing (MWDWS) process with EDTA solution. The bonding reaction of EDTA with LT is verified by Raman element and Vickers hardness testing. This study uses a single wire sawing machine (SWSM) to experimentally verify the efficiency of chemical reaction on the surface of lithium tantalate. Results of this study show that the surface roughness of as-cut lithium tantalate wafer surface can be effectively improved by the EDTA assisted wire slicing process with Sa 39.1%, Ra 38.8%, and Rz 33.2%. Furthermore, result shows can improve Sa 9.2%, Ra 12.4%, and Rz 10.6% by MQL with EDTA solution. Results of SEM show that the shape of chips changed from granular to strip type. With commercial multi-wire slicing machine DWS-150, the material removal rate (MRR) with EDTA solution is increased by 10.7%, wafer non-uniformity (N.U.) decreased to 42.6%, and sub-surface damage reduces to 52%. Results of this study can be applied to the production process of lithium tantalate slicing process.

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