本研究觀察共晶錫鋅銲錫線材分別經電遷移試驗、時效處理後其顯微結構且探討其拉伸試驗結果，並觀察破斷面型態與其橫截面微觀組織，而後比較硬度測試結果。
微觀組織顯示，未經均質化處理的試片，電遷移試驗和時效處理後其顯微結構差異並不明顯。經均質化處理後的試片，通電30天後，錫基地上出現大量顆粒狀的富鋅相；經均質化處理後再時效30天的試片其顯微結構沒有觀察到類似的現象。拉伸試驗結果顯示，經均質化處理的試片其平均抗拉強度值約為45 MPa，抗拉強度隨通電時間的增加呈現線性下降的趨勢；經過均質化處理的試片其抗拉強度值隨時效熱處理時間增加而下降且最後維持定值。此外所有試片拉伸位移值之標準差均偏高，可能是富鋅相分佈不均勻所致。根據破斷形貌的觀察結果，未經任何處理、經均質化後再通電30天的試片皆屬於延性破壞且裂縫沿著富鋅相和β-Sn之間發生。
硬度測試數據顯示，在第15天之前，經均質化處理再通電的試片和經均質化處理再時效的試片其硬度值幾乎相同。但當時間超過15天，經過均質化處理再通電的試片其硬度值有明顯下降的趨勢；而經過均質化再時效處理的試片其硬度值則幾乎不變。

The research observed the microstructures of eutectic Sn-9Zn solder wires after electromigration test and heat treatment separately, investigated the result of tensile test, observed the morphology of fracture surface and its cross-sectioned microstructure, and finally compared the result of hardness test.
The observation of microstructure indicated electrons had little impact on the microstructure of sample without homogenization. But, a lot of Zinc-rich particles within the microstructure of sample with homogenization appeared in the Sn-matrix when the current stressing time was to 30 days. However, the same phenomenon did not appear in the aging case. The result of tensile test showed the average ultimate tensile stress of the samples with homogenization was about 45.5 MP. It decreased linearly with current stressing time. But the average ultimate tensile stress of the samples with homogenization decreased with aging time. Furthermore, standard deviation of tensile displacement of all the samples was extremely high. It might come from the non-uniform dispersion of Zn-rich phase. According to the observation of fracture morphology, as-prepared samples exhibited a ductile mode and samples with homogenization after current stressing for 30 days samples did, too. Moreover, cracks occurred at the boundary between the Zn-rich phase and β-Sn.
The result of hardness test indicated, before 15days, for samples with homogenization after electromigration test and heat treatment separately, these hardness values were nearly identical. But after 15 days, for current stressing case, there was an obvious decline for hardness value. However, for aging case, the value remained almost constant.

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