中文摘要：

随着移动终端的广泛应用,射频多芯片系统封装结构的小型化、系统的集成化将导致功率密度的直线上升,同时,芯片各异性的特点将产生温度分布不均的现象,从而催生亟需解决的热管理问题.针对包含5款芯片的典型的射频前端系统,在POP封装基础上,提出柔性基板封装结构设计方案,并应用ANSYS ICEPAK三维数值分析法进行仿真计算,验证得到如下结果：①柔板同层的温差降低到POP结构的6％,异层的温差降低到POP结构的4％,避免了热点的出现;②柔板封装结温随下层屏蔽罩的厚度增大而减小,但尺寸的变化对其影响相对较小;③与铝基相比,铜屏蔽罩能够起到更好的散热作用.研究结果为射频异构多芯片三维封装优化设计提供了参考方案.

英文摘要：

Miniaturization and integration are required in radio frequency （RF） multi-chips packages with the widely spreading of mobile devices.However,it makes the power density go straight up.At the same time,the differences between chips leads to non-homogeneity of whole structure.All above drive the improvement of therrmal management.For the case at hand,a novel structure of flexible substrate for a RF front end system was proposed.The model was based on POP （package on package） package including 5 typical chips.Meanwhile,3D simulation analysis by ANSYS ICEPAK was adopted.Results are as follows.①It is proved to perform excellently in eliminating hot pots by decreasing 6％ than the POP＇s temperature in the same layer,and decreasing 4％ than it between two layers.②It shows that the thicker the shield,the lower the junction temperature.However,the size effects little to it.③Compared to Aluminum,copper performs better in heat spreading.All above provides a reference for thermal design.