在早期封裝產業中主要使用金線作為打線接合材料，然而受到金價高漲的影響，且金線與鋁基板進行接合時容易產生介金屬化合物，促使許多替代材料紛紛被提出，常見的導線有銀線與銅線。銀線雖然具有非常優異的導電性及導熱性，但也容易與鋁基板生成介金屬化合物，且有電遷移的疑慮；銅線除了有良好導電性與導熱性、成本具競爭力等優勢外，銅與鋁形成介金屬化合物的速率也較金及銀低。因此，本研究以銅基導線為主題進行探討。此外，為了將介金屬化合物產生的影響排除，本研究導入銅基板進行實驗，探討銅導線與銅基板打線接合後的可靠度。
本研究對銅線添加微量的金、鈀及鉑，分別形成三元及四元銅微合金導線。金、鈀及鉑等貴金屬的添加可以提升導線的機械性質與化學穩定性，且微量的添加可以避免電阻值大幅提升。因此本研究將藉由機械性質與通電特性比較銅微合金導線在原線材及完成打線接合後的性質差異，並導入氯化試驗評估銅微合金導線之應用可靠度。
機械性質方面，添加微量的合金元素所產生的固溶強化可以提升導線的微硬度及抗拉強度，使銅微合金導線整體的機械性質表現優異。完成打線接合後，銅微合金導線仍有良好的第一銲點抗拉強度，顯示具良好接合可靠度。
通電特性方面，銅微合金導線隨著合金元素添加量上升，電阻值會有提高趨勢。通電循環方面，添加高熔點合金元素如鈀、鉑，可以使銅微合金導線有較好的通電循環表現。完成第一銲點打線接合後，針對兩種不同的電子流方向進行通電，當正極接於線材端，負極接於基板時，電子流經球部傳遞至頸部會發生堵塞現象，大量電子累積在頸部導致電阻值提升，進而使熔斷電流降低。
銅微合金導線經氯化試驗後，氯離子會沿著導線表面的晶界進行侵蝕，抗拉強度與延伸率皆與氯化處理前相近，並無明顯劣化，然而表面的侵蝕會導致通電循環壽命下降。
本研究顯示，銅微合金導線不論是原線材或打線接合後，在機械性質及通電特性方面都具有良好的性質。分析第一銲點打線接合，評估不同電子流方向對於銅微合金導線與銅基板之間造成的影響，可提供封裝工業應用參考。

In addition to the advantages of good electrical and thermal conductivity, and cost-competitiveness of copper wires, the rate of bonding copper wires and aluminum substrates to form intermetallic compounds is also lower than that of gold and silver. In this study, copper-based wires are used as materials for discussion. In order to eliminate the influence of intermetallic compounds on the bonding surface, copper substrates are introduced to investigate the reliability of copper wires and copper substrates after wire bonding. Copper wires are added with trace amounts of gold, palladium and platinum to form ternary and quaternary micro-alloyed copper wires, respectively. The addition of precious metals such as gold, palladium and platinum can improve the mechanical properties and chemical stability of the wire, and a small amount of addition can avoid a significant increase in the resistance value. Studies have shown that micro-alloyed copper wires have good properties in terms of mechanical properties and electrical properties, whether they are pure or wire-bonded. Through the bonding technology of the first solder joint and the second solder joint, the metallurgical behavior between the micro-alloyed copper wire and the copper substrate in different electron flow directions is clarified, and the relevant data can provide reference for packaging industry applications.

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