热循环载荷下BTC器件焊点应力分析与优化OA

Two PCB pads with different sizes and layouts are designed for bottom termination components(BTCs),and corresponding finite element models of BTC solder joints are established.Through finite element simulations and metallographic tests,the influences of pad design schemes and solder joint structural parameters on the stress of BTC solder joints under thermal cyclic loading are investigated.An orthogonal experimental design method is employed to formulate nine groups of BTC solder joint schemes with different combinations of solder joint length,width,and height parameters.The results demonstrate that the maximum stress of BTC solder joints based on pad type Ⅱ is lower,indicating that this pad design is superior.Solder joint height exhibits a significant effect on the maximum stress of solder joints,whereas the effects of solder joint length and width are insignificant.Consequently,the structural optimization of BTC solder joints is ultimately achieved.