目前電子工業中，Cu是最常使用的金屬材料，本研究在探討Cu添加微量金屬元素之Cu-2.35 wt.% Fe-0.12 wt.% Zn-0.07 wt.% P(C194)銅鐵合金，C194具有高強度、高導電率(60% IACS以上)、微細化結晶構造、耐蝕性強、良好焊接性、高耐軟化等特性，被廣泛應用於用於積體電路、發光二極體、三極管、IC晶片訊號等。本研究利用掃描式電子顯微鏡(scanning electron microscope, SEM; TM-3000)並搭配掃描式電子顯微鏡/能量分散光譜儀(energy dispersive spectrometer；SEM/EDS)深入探討三種無鉛銲料：Sn、Sn-3.0wt.%Ag-0.5wt.%Cu與Sn-0.7 wt.%Cu與C194基材以固體/固體反應偶在時效溫度125、150及175 oC下時效反應100至2000 小時之界面反應。
研究結果顯示，Sn/C194反應偶在125 oC下反應0-2000 小時，其界面處皆會生成(Cu,Fe)6Sn5相，而(Cu,Fe)3Sn相則只在125 oC時效1000小時、150oC時效500小時和175oC時效100小時後出現，而SAC/C194和SC/C194反應偶中也出現相同的情形。其中(Cu,Fe)3Sn相較晚生成原因為C194中的Fe原子固溶入銲料形成異質成核點，使初始迴銲之晶粒大小下降，並且抑制了(Cu,Fe)3Sn相的生成速率。
本研究中，此三個系統之介金屬相厚度與反應時間之平方根呈線性關係，反應機制皆為擴散控制所主導。

At present, Cu is the most commonly used metal material in the electronics industry. In this study, Cu-2.35 wt.% Fe-0.12 wt.% Zn-0.07 wt.% P(C194) copper-iron alloys with trace metal elements added to Cu were investigated. C194 has the characteristics of high strength, high electrical conductivity (above 60% IACS), fine crystal structure, strong corrosion resistance, good solderability, high softening resistance, etc. It is widely used in integrated circuits, light-emitting diodes, triodes , IC chip signal, etc. In this study, a scanning electron microscope (SEM; TM-3000) and a scanning electron microscope/energy dispersive spectrometer (SEM/EDS) were used to deeply investigate the interfacial reaction of three lead-free solders: Sn, Sn-3.0wt.%Ag-0.5wt.%Cu and Sn-0.7wt.%Cu react with C194 substrate with solid/solid reaction couple at aging temperature 125,150 and 175 oC for 100 to 2000 hours.
The research results show that the Sn/C194 reaction couple reacts at 125 oC for 0-2000 hours, and the (Cu,Fe)6Sn5 phase will be formed at the interface, while the (Cu,Fe)3Sn phase is only formed at 125 oC for 1000 hours, 150oC for 500 hours and 175oC for 100 hours, and the same situation occurs in the SAC/C194 and SC/C194 reaction couples. The reason for the late formation of (Cu, Fe)3Sn phase is that the Fe atoms in C194 dissolve into the solder and form heterogeneous nucleation points, which reduces the grain size of the initial reflow and inhibits the formation rate of (Cu,Fe)3Sn phase.
In this study, the intermetallic phase thickness of these three systems is linearly related to the square root of the reaction time, and the reaction mechanisms are all dominated by diffusion control.

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