本研究添加鈦元素(0.02wt%)於Zn-25Sn銲錫合金中，分別與銅、鎳基板接合並經過多重迴焊製程後，探討界面介金屬化合物及其成長動力學，並分析介金屬化合物微結構的變化。微結構觀察分析結果顯示，合金部份由富鋅相及鋅錫共晶相所組成，所添加之鈦元素大多散佈在共晶相中；合金與銅基板間包含靠近銲錫合金的ε-CuZn5及靠近銅基板的γ-Cu5Zn8兩種介金屬化合物，銲錫合金中的富鋅相會與CuZn5相接；合金與鎳基板間則僅生成γ-Ni5Zn21一種介金屬化合物，銲錫合金中的共晶相會與Ni5Zn21相接。介金屬化合物成長動力學分析結果顯示，CuZn5及Cu5Zn8的成長機制皆為反應控制，銲錫中未添加鈦時，成長活化能分別為62.12kJ/mol及32.56kJ/mol；銲錫中添加0.02wt%鈦後，會使兩者的成長活化能上升，分別為92.70kJ/mol及39.46kJ/mol；Ni5Zn21的成長機制亦為反應控制，銲錫中未添加鈦時，成長活化能為9.23kJ/mol；添加鈦元素(0.02wt%)會顯著提升其成長活化能至95.63kJ/mol。針對Cu5Zn8介金屬化合物之微結構觀察結果顯示，迴焊試片之Cu5Zn8是由晶粒尺寸差異不大的等軸晶所構成，經多重迴焊製程後，接近銅基板的部份生成晶粒尺寸更小的細等軸晶，隨著迴焊次數增加，細小等軸晶的數目會隨之增加，使整體厚度增長。根據晶粒型態與晶粒大小的差異，Ni5Zn21介金屬化合物具有四個分層。

In this study, titanium(0.02wt%) was added to the Zn-25Sn solder alloy, which was joined to the Cu/Ni substrates and then subjected to multiple reflow processes. Subsequently, interfacial intermetallic compounds and its growth kinetics were discussed, and the microstructure evolutions of IMCs were analyzed. The microstructure investigation show that the alloy was composed of Zn-rich phase and Sn-Zn eutectic phase, and the titanium added was mostly dispersed in the eutectic phase. Solder/Cu interface consisted of ε-CuZn5 near solder and γ-Cu5Zn8 near Cu substrate. The Zn-rich phase in solder alloy was connected to CuZn5. There was only one intermetallic compound, γ-Ni5Zn21, formed at the solder/Ni interface. The eutectic phase in solder alloy was adjacent to Ni5Zn21. Growth kinetics analysis showed that the growth mechanism of CuZn5 and Cu5Zn8 was reaction-controlled, and the growth activation energy of these two IMCs would be 62.1kJ/mol and 32.6 kJ/mol, respectively, if no titanium was added into the solder. After addition of 0.02wt% Ti, the growth activation energy increased to 92.7kJ/mol and 39.5kJ/mol. The growth mechanism of Ni5Zn21 was also reaction-controlled, and the growth activation energy of Ni5Zn21 would be 9.2kJ/mol if titanium was not added into the solder. After Ti addition(0.02wt%), the growth activation energy significantly increased to 95.6kJ/mol. Based on the microstructure observation for Cu5Zn8 IMC, Cu5Zn8 of the as-reflowed specimen was composed of equiaxed grains. After multiple reflow process, fine equiaxed grains appeared near Cu substrate. With the increment in reflow cycles, the number of fine equiaxed grains increased, thus leading to the increment in Cu5Zn8 thickness. Based on the grain structure, Ni5Zn21 IMC possessed four sublayers.

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