2008-01-012024-05-17https://scholars.lib.ntu.edu.tw/handle/123456789/680389摘要：因應歐盟「電子產品禁用有毒物質（ROHS）」及「電子電機產品廢棄物回收（WEEE）」指令，電子產業正全力開發傳統鉛錫合金的替代材料，目前較具潛力的無鉛銲錫組成包括：Sn3.5Ag、Sn0.7Cu、Sn3Ag0.5Cu、Sn9Zn、Sn58Bi、Sn51In等。最近許多文獻報導銲錫合金添加稀土元素可以改善其潤濕性、抑制接合界面脆性介金屬化合物及提高機械性質(強度、破斷伸長率與抗潛變性)，然而本實驗室首度發現含稀土無鉛銲錫表面會形成錫鬚，而錫鬚成長可能引發接點短路造成電子元件使用失效。 本計畫將有系統的驗證各種無鉛銲錫合金添加不同稀土元素（Ce、La、Lu及La+Ce）的物理與機械性能，包括：熔點、潤濕性、高溫拉伸性質、抗腐蝕性、接合強度及動態疲勞特性；其次針對錫鬚問題，本計畫將尋求其抑制方法，根據先前研究，錫鬚成長的解決對策之一應在於細化銲錫內的稀土析出物尺寸，可能的方法包括：控制凝固速度、降低稀土元素含量及添加可細化稀土析出物的合金元素，均將於本計畫內加以確認；最後將針對含稀土無鉛銲錫產品的製造技術，研發可以量產化的鑄錠熔煉步驟以及含稀土錫球、錫粉與錫膏製程，製造技術研究亦將涵蓋電路板銲墊及引腳架表面處理所需的含稀土無鉛銲錫電鍍參數（電鍍液成分與電鍍條件）。 <br> Abstract: In response to the “Restrictions of Hazardous Substances in Electronic Products (ROHS)” and “ Waste Electrical and Electronic Equipment(WEEE)“ in the EU, the electronics industries have devoted their energies to the development of substitute materials for traditional Pb-Sn solder alloys. At present, the Pb-free solder compositions with potential include: Sn3.5Ag, Sn0.7Cu, Sn3Ag0.5Cu, Sn9Zn, Sn58Bi, Sn51In, et al. Recently many works have reported that the addition of rare earth elements into solder alloys can improve their wettability, inhibit the brittle interfacial intermetallic compounds of solder joints, and increase the mechanical properties (strength, fracture ductility and creep resistance). However, our laboratory discovered for the first time that tin whiskers formed on the surface of rare earth-doped Pb-free solders. It is known that such whiskers can cause short circuits in solder joints and lead to the failure of electronic devices in application. This project will systematically verify the physical and mechanical performances of various Pb-free solders added with rare earth elements (Ce, La, Lu and La+Ce), such as melting points, wettability, high temperature tensile properties, corrosion resistance, bonding strength, and dynamic fatigue characteristics. Furthermore, addressing the tin whisker problem, this project will try to find out the methods for the inhibition of whisker growth. According to our previous study, a strategy to solve the problem of whisker growth is to refine rare earth containing precipitates in solders. The possible methods include controlling the solidification velocity, decreasing the content of rare earth elements, and the addition of alloying elements for the refinement of rare earth containing precipitates. These methods will be confirmed in this project. Finally, the project will focus on the manufacturing techniques of rare earth-doped Pb-free solders to develop the melting procedures of ingots and the process of rare earth containing solder balls, solder powders, and solder pastes for mass production. The studies of manufacturing techniques will also involve the electroplating parameters (electroplating solutions and conditions) of rare earth-doped Pb-free solder for the surface finishing of solder pads on printed circuit boards and lead frames.無鉛銲錫稀土元素有益效應錫鬚成長Pb-free soldersrare earth elementsbeneficial effectswhisker growth