銲料在電子構裝中作為基板與電子元件重要的連結材料，目前以Sn-Ag-Cu無鉛銲料最被廣泛使用。本研究目的在於添加0-0.07 wt%多壁奈米碳管於Sn-3.0Ag-0.5Cu錫膏中，藉以提升無鉛銲料的性質。對於所形成的複合銲料分別進行顯微結構觀察並與銅基材進行界面反應以及熱、電和潤濕性質的分析，探討碳管加入後對無鉛銲料性質的影響。
在顯微結構中顯示，經過迴焊後碳管仍散佈於複合銲料中，且碳管添加量0.07 wt%時有糾結嚴重的現象。隨著碳管的添加量增加，介金屬相也產生變化。界面反應在100-200oC下進行5-30小時的時效處理，從150oC時效30小時開始，碳管添加量0-0.07 wt%的複合銲料與銅基材所形成的反應偶，其界面端的Cu6Sn5相形態皆會從扇貝狀轉變為層狀，並在Cu6Sn5與銅基材間生成了Cu3Sn相。而由於碳管的加入阻礙銲料與銅基材間原子的擴散，抑制了Cu6Sn5與Cu3Sn相生長。使在時效溫度增加與時間增長下，隨碳管添加量增加至0.05 wt%，其介金屬相生長速率都顯得越低，且需較高活化能才使介金屬相生長的現象。但在碳管添加量0.07 wt%時，銲料內部的碳管糾結嚴重，使得銲料與強化相間產生相分離，造成的複合銲料性質較不穩定，生長速率介於碳管添加量0與0.01wt%的生長速率之間。
其他性質方面，液化溫度在碳管添加量增至0.05和0.07 wt%時，略為下降至1oC；電性質方面隨碳管的加入較無明顯的影響；潤濕性質則是在碳管添加量0.05 wt%時，潤濕角度從57.6o下降至52.5o，具有最佳潤濕效果。經過各項分析後，本研究的複合銲料系統以SAC-0.05MWCNTs的組成有最佳之性質。

As is known, solders are essential to electronic industry. Recently, with the fast development of electronic products and the ever-stricter service requirement of the packaging industry, it is vital to enhance the property of solders, which act as interconnecting joints in electronic device.
In this study, the composite solders were produced mechanically by intermixing 0-0.07 wt% multi-walled carbon nanotubes(MWCNTs) into Sn-3.0Ag-0.5Cu solder. The objective of this study is to investigate the effects of the addition of carbon nanotubes on composite solders’ microstructure, thermal property, electrical resistivity, wettability and interfacial reaction with copper plate.
The microstructure of the composite solder shows that with the addition of MWCNTs, a larger number of Ag3Sn phases precipitates in the solder matrix while the Cu6Sn5 phases are retarded. Also, the grain morphology of both phases has somehow changed.
Isothermal aging was performed at 100oC to 200 oC for 5 to 30 h. During the aging process, the morphology of Cu6Sn5 changed form scalloped-shaped type to layer type. Meanwhile, with the addition of MWCNTs, the growth rate of Cu6Sn5 and Cu3Sn phases is restrained, and more activation energy is required, compared to unreinforced solders. In particular, it is indicated in this study that, the addition of 0.05 wt% MWCNTs to the Sn-3.0Ag-0.5Cu solder has the optimum reliability.
On the other hand, liquefacient temperature decreased slightly as the effect of doping MWCNTs. As for the electrical resistivity, the presence of MWCNTs did not degrade the electrical performance. The optimum wettability of the composite solder is SAC-0.05MWCNTs. Therefore, SAC-0.05MWCNTs composite solder may be a suitable substitute for SAC solder.

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