封装堆叠的温度场分析和参数研究

Temperature Field Analysis and Parametric Study of the Package-on-Package

封装堆叠(POP)装配前可对单个器件先进行测试,保证了更高的良品率,但具有更复杂的整体结构。采用有限元法,考虑了POP封装表面自然热对流条件,对实际的POP器件在工作情况下进行热传分析,并通过实验验证了计算结果的准确性。基于该计算模型,研究了POP芯片功率与顶层和底层封装最高温度差值之间的关系,并提出了POP热管理的策略。此外,进行了参数化研究,分析了关键位置不同材料热导率对POP封装温度场的影响。研究发现,印刷电路板(PCB)和底部衬底热导率的增大可以有效降低POP封装的最高温度。

The package-on-package（POP） devices can be fully tested before assembly to achieve higher stacking yield,but it has more complex structures.The thermal analysis of an actual POP device under its working state was performed by considering the natural thermal convection on the POP device＇s outer surfaces based on finite element method.The computational results were verified by designed experiments.Through the method,the relationships between the die power and difference values of the maximum temperature of the top package and bottom package were studied and the strategy for POP thermal management was proposed.Besides,the parametric study was carried out to analyze the effect of different material＇s thermal conductivities on POP temperature field.The results reveal that the thermal conductivity increase of printed circuit board（PCB） and bottom substrate could reduce the maximum temperature in POP effectively.