近年來，為了改善無電鍍鎳浸金(ENIG)中的”黑墊(black pad)”
問題，無電鍍鎳鈀浸金(ENEPIG)迅速地發展。無電鍍鎳鈀浸金板與
銲料接合後，無電鍍鈀層迅速的溶入銲料中並且延緩介金屬化合物
(IMC)的生成。目前有許多文獻，針對無電鍍鎳鈀浸金板與銲料的界
面反應進行探討，然而，鈀如何影響介金屬化合物的形成以及銲料接
點的強度仍是未知的。本研究將鈀添加至錫銀銅銲料中，觀察銲料的
微結構變化。並將銲料與無電鍍鎳金板進行迴焊(reflow)，於不同溫
度下進行熱處理，觀察其生成的介金屬化合物厚度與成分變化。此
外，利用高速撞擊測試(high-speed impact test)去評估微量鈀摻雜對接
點可靠度的影響。
無電鍍鎳浸金板與錫銀銅鈀銲料接合後，鎳原子擴散到銲料中
並與銲料產生反應，在界面生成高Ni-(Cu,Ni)6Sn5。經過長時間的熱
處理，銲料中過飽和的銅與鎳擴散到介面，並與錫產生反應，低
Ni-(Cu,Ni)6Sn5 生成於界面中。鈀的添加可減緩界面(Cu,Ni)6Sn5 的生
長並且抑制低Ni-(Cu,Ni)6Sn5 的析出，進而促進介金屬化合物的穩定
性。最後，提出鈀影響界面反應的可能原因並與場發射電子微探儀的
分析結果相互印證。
在錫銀銅鈀銲料與無電鍍鎳金板液態反應的過程中，除了
(Cu,Ni)6Sn5 的析出外，Ni3P 與Ni3SnP 相亦生成在(Cu,Ni)6Sn5 化合物
下方。隨著反應時間的增加，介金屬化合物的厚度亦隨之增加，其中，
Ni3P 層的成長甚為快速。在撞擊測試中，Ni3P 的快速生長明顯地降
低銲料接點的可靠度。摻雜鈀於銲料中，不僅能抑制界面(Cu,Ni)6Sn5
的生長，亦可以延緩鎳從ENIG 板端的擴散，減低Ni3P 層成長的速
度，進而有效的提升銲料接點的強度。根據這些研究結果可以得知錫
銀銅鈀合金是個具有潛力，且適合應用於未來銲料設計的材料。

Electroless Nickel/Electroless Palladium/Immersion Gold
(ENEPIG) surface finish has been developed to overcome the “black pad”
issue of Electroless Nickel/Immersion Gold (ENIG) recently. After
reflow, the electroless Pd layer of ENEPIG would dissolve into solder
matrix, which might reduce the growth of IMCs. However, the Pd
distribution and detailed mechanism how Pd influences the interfacial
reaction and reliability of solder joints are not yet clear. In the study,
Sn3.0Ag0.5Cu (SAC305) solder doped with 0~0.5 wt.% Pd was used to
reflowed with ENIG substrate. Before aging, most Pd atoms would
dissolve in eutectic phase. After aging, Pd concentrated in Cu6Sn5 and the
maximal solubility was around 0.16 at.%. In addition, nanoindentation
testing revealed that the Pd doping would soften Cu6Sn5 phase, and then
influence the hardness of SAC305-xPd solder.
In the solid reaction of SAC305-xPd solder and ENIG substrate, Ni
dissolved into solder and (Cu,Ni)6Sn5 formed at the interface. As the Pd
concentration increased in the solder, the formation and growth of
(Cu,Ni)6Sn5 were suppressed. After thermal aging, two types of
(Cu,Ni)6Sn5 IMC, i.e. high Ni (H) and low Ni (L) were observed at the
IX
SAC305-xPd/ENIG interface. As compared to H-(Cu,Ni)6Sn5, more Pd
dissolved in the L-(Cu,Ni)6Sn5. Besides, Pd doping enhanced the growth
of H-(Cu,Ni)6Sn5 and slowed down the formation of L-(Cu,Ni)6Sn5,
which would stabilize the IMCs. Based on the quantitative analysis by
field emission electron probe microanalyzer (FE-EPMA), the correlation
between Pd doping and interfacial reaction in solder joints was probed
and discussed.
In the liquid reaction of SAC305-xPd solder and ENIG substrate,
Ni3P and Ni3SnP phases were observed between the (Cu,Ni)6Sn5 and Ni
substrate. With the increased reflow time, the IMCs grew rapidly,
especially the Ni3P layer. When Pd was added into the solder, not only
the formation of interfacial (Cu,Ni)6Sn5 was restrained, but also the Ni
diffusion from ENIG substrate was delayed. To evaluate the Pd effect on
the reliability, the impact test was employed. The impact test showed that
the Pd doping would increase the bonding strength, which was due to the
reduced Ni3P thickness. The role of Pd in the solder joint reliability was
addressed and proposed. This study aimed to evaluate the potential
application of novel Pd-doped lead-free solders for future solder designs.

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