为了提高球栅阵列焊点封装器件的自组装成品率,研究了焊点体积偏差率及焊盘直径对器件自组装成品率的影响。考虑封装器件的温度翘曲变形、焊点体积的不可避免的制造误差及焊点位置的随机性,分析了器件自组装过程。通过求解不同体积焊点的形态,得到了不同体积焊点的液桥刚度曲线。基于不同体积焊点的液桥刚度曲线,仿真分析了焊点体积偏差率及焊盘直径对器件自组装成品率的影响。结果表明,焊点体积偏差率及焊盘直径的减小会增大焊点液桥刚度曲线的公共范围,从而提高器件的自组装成品率。
The influences of the deviation rates of volume of the solder joints and diameters of pads on the yield of self-assembly were studied to improve the yield of BGA components.Considering the thermal warpage,the unavoidable deviations in the manufacture of the volume of solder joints and the randomness of the positions of solder joints,the processes of self-assembly were discussed.The stand-off curves of solder joints with different volumes were obtained according to solving the shapes of solder joints.Based on the stand-off curves of solder joints,the influences of the deviation rates of volumes of the solder joints and diameters of pads on the yield of self-assembly were simulated.The common range of the stand-off curves of solder joints and the yield are increasing with the decreasing of the deviation rates of volumes of the solder joints and diameters of pads.