Yang Linmei, Quan Shanyu, Liu Cong, Xiong Hao
Shenyang University of Technology, Shenyang 110870, China.
J Nanosci Nanotechnol. 2020 Apr 1;20(4):2573-2577. doi: 10.1166/jnn.2020.17203.
The reliability of solder joints, which is affected largely by the interfacial intermetallic compounds layer, is of great importance to the performance of electronic devices. In this paper, a novel composite solder with Mo nanoparticles doped in Sn3.0Ag0.5Cu solder was prepared. Solder/Cu joints were prepared using Sn3.0Ag0.5Cu solder or Mo nanoparticles reinforced solder with Cu substrates. The effect of the nanoparticles on the growth of intermetallic compounds during isothermal aging was investigated. It was found that the addition of Mo nanoparticle markedly suppressed the increase in thickness of the interfacial intermetallic compounds layer during isothermal aging. The atomic diffusion coefficients during isothermal aging in Sn3.0Ag0.5Cu solder and in the novel doped solder were determined experimentally. Mo nanoparticles were found to decrease the diffusion coefficient in the composite solder. The high specific surface area of the nanoparticles makes them easily adsorbed and hinders the diffusion of Sn and Cu atoms. This is consistent with an increase in the diffusion activation energy due to the addition of Mo nanoparticles in Sn3.0Ag0.5Cu solder.
焊点的可靠性在很大程度上受界面金属间化合物层的影响，对电子器件的性能至关重要。本文制备了一种在Sn3.0Ag0.5Cu焊料中掺杂Mo纳米颗粒的新型复合焊料。使用Sn3.0Ag0.5Cu焊料或Mo纳米颗粒增强焊料与Cu基板制备了焊料/Cu接头。研究了纳米颗粒在等温时效过程中对金属间化合物生长的影响。结果发现，添加Mo纳米颗粒显著抑制了等温时效过程中界面金属间化合物层厚度的增加。通过实验测定了Sn3.0Ag0.5Cu焊料和新型掺杂焊料在等温时效过程中的原子扩散系数。发现Mo纳米颗粒降低了复合焊料中的扩散系数。纳米颗粒的高比表面积使其易于吸附，并阻碍了Sn和Cu原子的扩散。这与在Sn3.0Ag0.5Cu焊料中添加Mo纳米颗粒导致扩散活化能增加是一致的。
