On the mechanism of the binary Cu/Sn solder reaction
On the mechanism of the binary Cu/Sn solder reaction
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DOI：
10.1063/1.1852724
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发表时间：
2005-01
影响因子：
4
通讯作者：
J. Görlich;G. Schmitz;K. Tu
中科院分区：
文献类型：
--
作者：
J. Görlich;G. Schmitz;K. Tu
用扫描和透射电子显微镜研究了铜与熔融纯锡的钎料反应。与已报道的SnPb焊料类似，金属间化合物Cu6Sn5产物以扇贝状形态形成，其生长动力学与时间的立方根成正比。实验确定了扇贝的大小分布和形状。比较了二元反应偶铜锡和工艺组合铜锡铅，发现单个扇贝的长宽比有显著差异。我们用透射电子显微镜证明，相邻扇贝不是由焊料通道分隔的，而是由晶界分隔的。因此，晶界迁移是速率控制步骤，观察到的扇贝形状变化是由于两个反应对界面张力的不同造成的。
The solder reaction of Cu and molten pure Sn is studied by scanning and transmission electron microscopy. Similar as reported for SnPb solder, the intermetallic Cu6Sn5 product is formed in a scallop-like morphology and a growth kinetic proportional to the cube root of time is found. Size distributions and shape of the scallops are determined experimentally. Comparing the binary reaction couple Cu/Sn with the technical combination Cu/SnPb, a significant difference in the length to width aspect ratio of individual scallops is noticed. We demonstrate by transmission electron microscopy that neighbored scallops are not separated by channels of solder, but by grain boundaries. Thus, grain boundary transport is the rate controlling step and the observed variation in scallop shape is due to differences in the interface tensions of the two reaction couples.