在本研究中，我們將銅墊層鍍上2 μm 的薄銲錫，並反應成介金屬化合 物，作為銅原子擴散的阻擋層。當試片再接上銲錫時，介金屬化合物的成 長將被抑止。在同樣的迴銲時間下，減少的介金屬化合物至少在1 μm 厚以 上，銅墊層的消耗也降低1~2 μm 厚，效果顯著。考慮迴銲前 10 分鐘的反 應速率 k 值，從中也可看到，有阻擋層的試片為3.12 10 ，較 無阻擋層的 5.40 10 少了一個數量級。
對於抑止的機制我們也作出多方的驗證。銅原子主要藉由介金屬化合物 之間的通道從銅墊層擴散至銲錫內反應，因為銅原子的擴散途徑在迴銲之 後大幅減少，達成抑止介金屬化合物成長的效果。
兩種錫銅介金屬化合物Cu6Sn5與 Cu3Sn，我們也作出抑止效果的比較與 分析。以密合的Cu6Sn5做為擴散阻擋層，在迴銲時間拉長時還是會有大量 的介金屬化合物生成。倘若以Cu3Sn 做阻擋層，則在迴銲時間前 10 分鐘時 幾乎沒有大量的介金屬化合物生成，但是在10 分鐘之後開始有部分位置形 成大塊的Cu6Sn5。考慮迴銲前10 分鐘的反應速率 k 值計算，以 Cu3Sn 做阻 擋層的試片為4.38 10 ，以密合的 Cu6Sn5做為擴散阻擋層的為 9.48 10 ，由此可觀察到抑止的現象的確是以Cu3Sn 做阻擋層 效果較好。
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除此之外由於純錫與銅的反應速率比錫銀銲錫與銅反應速率來的快，因 此在錫銀凸塊結構的試片得到的 n 值與 k 值皆與純錫薄膜結構的試片不 同。
最後，在迴銲時間拉長時，Cu3Sn 與銲錫之間會局部生成異常巨大的 Cu6Sn5，此異常晶粒成長(Selective Grain Growth)的現象在 Kim 等人[46]的 文獻中提到也發生在錫鎳介金屬化合物中，初步推斷造成此現象的原因來 自於Cu6Sn5晶體面向(Faceted)的不同，相關的問題尚待我們深入的研究與
克服。
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