本論文在探討鍍金層對Bi-43Sn與Sn-9Zn BGA銲料迴銲後之接點強度影響及二元銲錫在不同溶液之電解質遷移行為。為了探討金層對於BGA銲接點強度影響，先在鍍鎳(5µm)銅銲墊上電鍍0.1 ~ 1.2 µm金層，再分別與Bi-43Sn及Sn-9Zn銲球進行迴銲，迴銲後即進行剪力量測，結果顯示：隨著金鍍層愈厚，Bi-43Sn銲料的強度愈差，而Sn-9Zn銲料的強度則些微增強。 二元銲錫(Sn-3.5Ag, Bi-43Sn, Sn-0.7Cu, In-49Sn, Sn-37Pb 和 Sn-9Zn) 分別在蒸餾水、0.01M NaCl、 0.01M (NH4)2SO4及水溶性助銲劑水溶液中，施以5V偏壓，進行遷移研究。結果顯示：Sn-Ag 和Sn-Pb 系統在蒸餾水有明顯的電解質遷移行為，然而在0.01M (NH4)2SO4水溶液中卻沒任何的遷移現象，在含氯的水溶液中，所有的二元銲錫均有嚴重的電解質遷移。 在0.01M (NH4)2SO4水溶液中進行陽極動態極化掃描及定電位陽極反應，配合ESCA表面分析，得知Sn-Ag和Sn-Pb在表面會生成SnO2層，因此抑制遷移行為。 Shear strength of the ball grid array (BGA) Bi-43Sn and Sn-9Zn solder balls re-flowed on the Ni/Au-coated Cu-pads was estimated. The strength of the joint between the re-flowed solder ball and the Ni/Au-coated pad was influenced by the thickness of the Au-coating. For the Bi-43Sn soldering system, the shear strength decreased gradually with increasing the Au-coating from 0.5 to 1.2 μm, and abruptly at thickness greater than 0.1 μm. In contrast, for the Sn-9Zn soldering system, the strength increased gradually with the thickness of the Au-coating. The electrolytic migration of some tin-based binary solder (i.e., Sn-Ag, Sn-Bi, Sn-Cu, Sn-In, Sn-Pb and Sn-Zn alloy) was explored in various solutions (e.g., de-ionized water, 0.01M (NH4)2SO4, 0.01M NaCl and aqueous flux solution -containing 2.2 mM chloride ion) at a dc-bias of 5V. The Sn-Ag and Sn-Pb systems were susceptible to electrolytic migration in de-ionized water but immune to migration in 0.01 M (NH4)2SO4 solution. All the binary systems in this work were facilitated to migration in the chloride solution. Potentiodynamic and potentiostatic polarization for various soldering systems were compared. X-ray photoelectron spectroscopy (XPS) of the corrosion products on the anode and the dendrites across the electrode were examined. The results from the electrochemical polarization and the XPS analyses were helpful in elucidation of the distinction on migration behavior of various soldering systems.
