打線封裝製程中，金線因質脆、導電性差之介金屬化合物成長過快且價格逐年升高之下，使價格相對低廉且導電、導熱性較優的銅線受到重視。但銅易氧化且機械性質過高，導致良率不佳，限制了銅線的發展與使用。導電性最佳的銀線曾受到矚目，但由於電解離子遷移、濕氣腐蝕及擴散差異所造成的孔洞等諸多阻礙，成為銀線不被看好的主因。
本論文擬對新興的打線材料銀-金-鈀合金線(Ag-8Au-3Pd)與銀-鈀合金線(Ag-3Pd)進行材料介金屬成長之研究。在以不同接合能量參數接合，並經過高加速溫度濕度未飽和蒸氣應力測試（HAST）與高溫儲存測試（HTST）下，銀/鋁與銀-金/鋁之介金屬化合物隨著時間變化與成長。儀器方面以FE-SEM觀察介金屬厚度的演化，並利用能譜分析儀(EDS)與背向散射電子分析儀(EBSD)鑑定介金屬化合物的元素成分與晶體結構。本論文測得HTST可靠度測試2000小時之下銀-金-鈀合金線與銀-鈀合金線之平均厚度為2.52與1.63微米。透過經驗指數關係式求得銀-金-鈀合金線動力學參數n值於HAST與HTST下分別為0.093以及0.123，屬擴散控制反應；銀-鈀合金線則為0.604及0.642，屬反應-擴散混合機制。銀-金-鈀合金線與銀-鈀合金線分別於HTST可靠度測試500小時與1000小時出現裂縫，顯示銀-金-鈀合金線的可靠度較差。
最後，比較銀合金線與鍍鈀銅、銅-鈀合金線之可靠度測試結果，得到銀合金線之介金屬化合物厚度厚於鍍鈀銅與銅-鈀合金線，得到銀-鈀合金線可靠度測試較優秀之結論。

Gold wire bonding is one of the oldest and most mature process due to its high yields and low processing costs. However, Kirkendall effect in Au/Al interface has been an important issue in gold wire bonding process. With slower IMC layer growth and cheaper cost, copper wires have recently been reckoned as a candidate. However, the oxidation and strong mechanical property shortened the applications. In addition to copper wires, silver wires have the best electric and thermal conductivity, but they have problem in their humidity corrosion, electrolyte migration phenomena and Kirkendall effect.
In this study, we focused on Ag/Al and Ag-Au/Al intermetallic compounds (IMCs) analysis using Ag-3Pd and Ag-8Au-3Pd wires. SEM, EDS and EBSD techniques were applied to characterize the IMC layers at the bonded interfaces, the chemical composition and structures analysis of IMCs after HTST and HAST reliability aging tests.
The IMC average thicknesses was measured 1.6 μm in Ag-3Pd wires and 2.52 μm in Ag-8Au-3Pd wires after HTST 2000 hours. We can clearly determine the tendency of IMC growth in Ag-3Pd and Ag-8Au-3Pd wires respectively. The kinetics parameter n, no matter in HTST or HAST, were calculated to be 0.093 and 0.123, which were diffusion controlled reactions in Ag-8Au-3Pd wires; 0.604 and 0.642, which were diffusion-reaction mixed mechanism in Ag-3Pd wires. We found cracks formed in Ag-8Au-3Pd wires after HTST 500 hours earlier than those in Ag-3Pd wires after HTST 1000 hours.
Based on what we observed in IMC thicknesses evolution and cracks formation, by comparing the differences between silver alloy and copper wires, thicker IMCs were found in silver alloy wires, which will provide better bondabilities. At last, we found Ag-3Pd wires to be the best wire materials of all.

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