苛刻环境下多芯片FC-PBGA器件板级温循可靠性研究

Research on the Board Level Temperature Cycle Reliability of the Multi-chip FC-PBGA Devices under Harsh Environment

研究了宇航用多芯片扁出型倒装芯片球栅(FC-PBGA)器件在温度循环下的板级可靠性。通过宏观形貌观察、微观结构演变等手段对温循后的器件进行了分析,并利用有限元仿真对器件的疲劳寿命进行了评估。研究结果表明,经温度循环后FC-PBGA器件表面三防漆出现起皮现象,但封装组件未出现失效故障。器件中倒装芯片的布局对温度循环后危险焊点的位置具有显著的影响。危险焊点在温度循环后产生了明显的塑性变形,在靠近芯片端的界面处形成了显微裂纹。通过有限元仿真结合修正的Coffin-Manson方程计算得到了组件的温度循环疲劳寿命约为1002次,具有较好的可靠性,为塑封器件的高可靠性应用提供了参考。

The board-level reliability of the multi fan-out flip-chip PBGA devices used in aerospace under temperature cycle is investigated.The macrostructure morphology and microstructure evolution of the devices after temperature cycling are analyzed,and the fatigue life is estimated with the finite element simulation method.The results showed that the conformal coating on the surface of the FC-PBGA device is twisted,but the package components do not fail after thermal cycling.The layout of the flip-chip in the device has a significant impact on the location of the dangerous solder joints.The dangerous solder joints produce an obvious plastic deformation and the micro-cracks are formed at the interface near the chip end after temperature cycle.The fatigue life of the device is calculated as 1002 cycles through the finite element simulation and the modified Coffin-Manson equation,which proves that the component has good reliability.It provides reference for the high reliability application of plastic packaging device.