无铅BGA 焊接工艺方法研究

以焊接无铅BGA器件为目的,在三种主要焊接工艺方法中选择有铅焊料焊无铅BGA的工艺方法.通过调整回流焊炉各温区参数,得到适用于这种工艺方法的温度曲线,并通过外观、X射线、染色与渗透、剪切力、金相剖切对焊接质量进行分析.分析结果表明:该工艺方法焊接的无铅BGA焊点外观符合目检要求；X射线下没有发现焊点的明显缺陷；环境试验后,焊点的剪切力符合标准要求；染色试验未发现被染色的焊球；焊点的金相图显示结合处焊接良好,且满足合格焊点的金属间化合物厚度要求(0.5～50 μm),这种工艺方法能够较好的完成无铅BGA器件的焊接,有一定的应用价值.

Research on Welding for Lead-Free BGA Process Method

For the purpose of welding lead-free BGA devices, among three main welding processes, lead-free
BGA reflow with Sn-Pb solder paste is chosen as process method. By adjusting the temperature zone reflow oven parameters
in order to get the approach of the temperature curve, and by looking at the appearance, X-ray, dye penetrant,
shear stress,metallographic, the conclusion can be made that lead-free BGA soldering technology with SnPb
solder paste passes through test. The result shows that the process method of lead-free BGA reflow with SnPb solder
paste can manage to weld lead-free BGA devices. The result shows that the method is reasonable an feasible.