本文研究目的在於Sn-Ag銲料系中添加不同比例的銻(Sb, 0、2.18及3.86wt.%)，探討Sb的添加對其熔點分佈與微結構組織之影響，以及銲料與Cu及Cu/Ni-P/Au金屬層基板銲接後，經過150˚C高溫熱儲存試驗，等溫低週疲勞之可靠度表現。將自行熔煉之Sn-3Ag-xSb銲料製作成直徑1.12mm的錫球。在銅片上分別利用無電電鍍及離子濺鍍鍍上Ni-P層及Au層，再將錫球與Cu/Ni-P/Au UBM及銅片做成單邊搭接的試件後，進行150°C高溫熱儲存，儲存時間為240及600小時。
　　研究結果顯示，Sn-3Ag-xSb銲料熔點隨著Sb的添加而上升，由Sn-3.5Ag的221.7°C上升至Sn-2.92Ag-3.86Sb的226.0°C，且固液相區間有擴大的趨勢。Sb的添加使得環狀結構會逐漸瓦解，β-Sn逐漸變大。添加2.18wt.%Sb時微結構與Sn-3.5Ag類似，仍呈現Ag3Sn與β-Sn枝晶所組成的環狀結構，其有較細緻的Ag3Sn，Sb以固溶的方式存在於β-Sn中；當添加量為3.86wt.%時，會有大小約數μm的層狀化合物Sn4Sb3生成。
　　疲勞測試方面，在±0.01mm的固定位移量下，未經熱儲存之銲點疲勞壽命以添加3.86wt.%Sb的銲料為最高，這是由於Sb的固溶強化及Sn4Sb3的析出強化造成此銲點有最少的塑性應變量，因此有最佳的疲勞壽命。在相同的測試條件下，添加Sb所造成銲料強度增加及破斷韌性下降，會降低荷重下降參數(ψ)曲線中穩定成長期與破壞加速期之間的過渡期ψ值，使得破壞加速期荷重下降佔總荷重下降的比例增加，這對可靠度有不利的影響。熱儲存過後銲料的軟化會使得過渡期之ψ值有上升的趨勢。此外荷重下降參數曲線穩定成長區的斜率越低，疲勞壽命有越高的趨勢。隨著熱儲存時間的增加及Sb含量的提高容易導致破斷位置發生在界面層上。未經熱儲存時，由於Sb的添加量只達到3.86%，因此所有銲點試件破斷面皆在銲料內發生；但Sn-2.92Ag-3.86Sb與Cu基板銲接，經過600小時熱儲存後，界面層Cu6Sn5與銲料及基板的交界會提供裂紋開裂的途徑，使得疲勞壽命急速的下降。然而所有銲料與Cu/Ni-P/Au金屬層基板接合的銲點，經過熱儲存600小時過後，裂紋並未從界面層Ni3Sn4與銲料及基板的交界開裂。而就銲料熔點、抗熱性、銲點剪切強度及疲勞壽命而言，Sn-3.15Ag-2.18 Sb銲料與Cu/Ni-P/Au基板接合的銲點有較佳的可靠度表現。

　　The goal of this research is to study the effects of various Sb additions (0~3.86 wt.%) on the melting temperature and microstructure of Sn-Ag solder and to evaluate the reliability of low cycle fatigue of the solder joints connected to Cu and Cu/Ni-P/Au UBM substrates after thermal storage at 150˚C. Sn-3Ag-xSb in form of solder balls with 1.12 mm in diameter are fabricated. Ni-P and Au layers are coated on the copper substrate by electroless plating and ion sputtering respectively. Solder balls were re-flowed with or without Cu/Ni-P/Au UBM in the form of single lap shear specimen, and then thermal storage was carried out at 150˚C. The times of thermal storage are 240 and 600 hours respectively.
　　Experimental results show that melting points of Sn-3Ag-xSb solders increase with the addition of antimony. The melting points rise from 221.7˚C of Sn-3.5Ag to 226.0˚C of Sn-2.92Ag-3.86Sb. In addition, the range between solidus and liquidus also expand with the addition of antimony. When the amount of antimony is 2.18 wt.%, the microstructure is similar to Sn-3.5Ag. It consists of β-Sn dendrite and interdendritic eutectic network. For Sn-3.15Ag-2.18Sb, Ag3Sn is finer and the atoms of antimony solved into the β-Sn dendrite. Laminar-liked Sn4Sb3 of several μm can be observed as the addition of antimony reaches 3.86wt.%.
　　The fatigue life test reveals that Sn-2.92Ag-3.86Sb has the best performance under the condition of constant displacement of ±0.010 mm without thermal storage. It may due to the less plastic strain of the Sn-2.92Ag-3.86Sb solder joint which solid-solution hardened by antimony addition and further precipitation hardened by Sn4Sb3. The addition of antimony results in an increase in strength, however, a decrease in fracture toughness. It decreases the ψ values at transition from steady-state to fracture acceleration stage on load-drop parameter curve. After thermal storage at 150˚C, there is a trend that the ψ values at transition increases due to the softening of the solders. In addition, the slope of steady-state stage on load-drop parameter curve is lowered which tend to raise the fatigue life. The increases of storage time and antimony addition result in the transition of fracture to occur on IMC. The fracture of all the solder joints without thermal storage occurs within the solder matrix. After thermal storage for 600 hours, interfaces of Cu6Sn5 between substrates and solder matrix provide the path of fracture to occur by Sn-2.92Ag-3.86Sb solder joint with copper substrates. The fatigue life decreases drastically. Solder joints on Cu/Ni-P/Au UBM substrates, even if after thermal storage of 600 hours, are still fractured within the solder matrix. Evaluation based on melting temperature, thermal resistance, shear strength, and fatigue life, Sn-3.15Ag-2.18Sb solder joints connected to Cu/Ni-P/Au UBM substrates reveal better performance and reliability among all specimens.

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