隨著電子產品輕薄短小的發展，電子構裝技術成為業界重要的領域，目前電子構裝技術中，球柵陣列封裝為最常見的方式，其中影響銲錫接點可靠度的因素包含錫球成分、尺寸和表面處理、迴焊條件等，本研究將針對銲錫錫球成分的改變作探討，並將研究分為兩大部分探討，一為電子軟焊接點之可靠度評價方式，另一為合金效應分析。
在過去的電子構裝技術中，人們大量使用Sn-Pb合金，然而Pb會使人染上疾病，所以歐盟在2003年時，通過危害物質限制令來限制Pb的使用，自此人們便開始尋找其他替代的合金，而最終得到目前廣泛使用的Sn-3Ag-0.5Cu合金，其擁有良好的潛變性質，不過亦有較弱的抗衝擊性質，並且高銀含量亦會造成成本提升，所以為了解決此問題，本研究藉由添加金屬元素來改變其合金組成，試圖降低Ag的使用，並提升接點可靠度。
首先本研究使用Sn-1Ag-0.8Cu做為基礎銲料，並在其中添加Ni、Co、Bi三種元素，用田口法配置32組試片，經歷一系列的研磨、拋光、微結構觀察之後，在過程中我們找到較省時的可靠度評價方法，並且有效率找出在掉落測試中表現最佳的銲料，汲取過去的經驗建立一套評價方式。之後再根據近年文獻中報導，提取對銲料接點可靠度有幫助的元素如Mn、Ti、Al、Fe、Ga等元素做添加，以計算熱力學輔助，經歷晶粒大小分析、硬度分析、高速拉推球試驗等可靠度評價方式之後，實際去做業界認可的可靠度評價方式，如掉落測試、溫度循環測試，最終達到建立可靠度評價方式，並且提供合金效應分析之結果供學界使用。

Lead-free soldering has been widely adopted by the electronics industry, with SnAgCu (SAC) having high Ag content being the initial main stream of choice. This selection was challenged later by the fragility of solder joint toward drop and the high cost of Ag. As a result, low Ag SAC was considered a solution for resolving both issues. In this study, we chose low Ag SAC alloy, designed the components by CALPHAD thermodynamic modeling, doped with Ni, Co, Bi, Mn, Ga, Al, Ti, Fe, these solders were evaluated under intermetallic compound thickness and roughness measurement, high speed shear and pull test, Vickers hardness test, grain size measurement, JEDEC drop test, thermal cycling test condition against SAC305, SAC105 and LF35(SAC1205-0.05Ni) alloys. After that we know the best evaluated method. Simultaneously, we found that SAC108-0.05Co and Sn-0.8Cu-1Ga have good drop performance, and SAC108Co also show good thermal cycling performance which is the potential solder to replace commercial Pb-Free solder.

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