現今電子封裝受到金價持續攀升影響，以其他系統之導線來取代金線製程成為發展趨勢。本研究選用線徑20微米的銀-鈀-金合金導線作為導線材料，除了有較低的成本優勢，也改善了以往純銀線在打線接合時，因為銀與鋁原子的擴散速率差異所造成在介金屬化合物層中產生孔洞情形；鈀及金的添加，亦能提高線材的拉伸性質及抗氧化性。
　　本研究透過200~400℃並持溫30分鐘之真空退火熱處理使線材組織均勻化，並調查退火後硬度及拉伸性質。退火後硬度及斷裂荷重隨著退火溫度的增加而下降，延性則是上升。在選定一適當的退火溫度後(350℃)，利用未退火與退火的線材對於兩者進行放電結球的特性調查。未退火與退火的線材在結球後都有良好的成球性，兩者球部皆呈現柱狀晶，並且在柱狀晶末端有第二支臂的生成。此外，本研究以電子微探儀調查球部中元素分佈，發現鈀有聚集在靠近頸部的情形。
　　在打線接合後，本研究於175℃並進行0、24、72、168小時之熱時效試驗，並以熔斷電流(0.45 A)之80%電流(0.36 A)進行持續2、12小時之通電試驗，探討導線與鋁基板接合界面的特性，並調查第一銲點之拉力強度。在接合界面的觀察，通電後的界面除了可能會因原子間擴散之外，也會因受到電流通過時，電子流方向的影響，使得鋁膜往球部移動顯著。而於熱時效試驗168小時後之接合界面觀察到孔洞，此孔洞應為原子間擴散而產生的Kirkendall voids。
　　銀-鈀-金合金導線與鋁基板接合後經過熱時效試驗至168小時後，仍能維持大於6 gf的接合強度。而通電2小時後，接合強度則降至4 gf，並且發現打線接合後拉伸的斷裂位置會因為通電而使得斷裂位置由未通電的HAZ區改為斷裂在隨機的線材端上。
　　與鋁基板接合的銀-鈀-金合金導線分別經過熱時效試驗以及通電試驗後，在第一銲點拉力測試中，皆未出現從基板剝離的情形發生，顯示銀-鈀-金合金導線與鋁基板有良好的接合性。最後在接合後I-V曲線電性調查發現，在同樣經過通電試驗或熱時效試驗後，與純銀線相比，銀-鈀-金合金導線電性都具有較佳的電性表現。

In this study, the tensile properties and hardness of Ag-2Pd-0.2Au alloy wires with Φ = 20 µm (0.8mil) were investigated. The microstructural characteristics before and after electric flame-off (EFO) process were also studied. The microstructures of the free air ball (FAB) were columnar grains and dendrites. To understand the relationship between the distribution of alloying elements and the microstructures of FAB, Electron Probe X-ray analysis (EPMA) was used. Experimental results indicated that Pd atoms segregated at upper region of FAB. Additionally, to verify the capability of Ag-2Pd-0.2Au alloy wires, bonded samples were tested under 175℃ for 24, 72 and 168 h (heat aging test). Ag-2Pd-0.2Au alloy wires retain good bondability that its bonding strength were about 6 gf. The electrical behavior of bonded samples after heat aging test were investigated and compared to the pure Ag wires. Ag wires degraded rapidly after heat aging test. Ag-2Pd-0.2Au alloy wires possessed better bonding performance than Ag wires.

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