Numerical simulation and thermal analysis of PoP packaging

Abstract

In this pa per, by establishing PoP (package-on package) packaging model, numerical simul ation method was us ed to conduct th e ste ady-state th ermal analysis under a gi ven power conditi on and th e in flu ence of th ermal conductivity of packaging materials, incl uding PCB (Printed Circuit Bo ard), th e number of chips and power distribution on the temperature of PoP packaging were explored. FInally, the distribution of stress field of package was also investigated bas ed on the results of temperature distribution. Simulation res ults show that th e highest temperature occurs in the center of the chi p and gr adually decreases to the surro unding environment. The increase of th ermal conductivity for packaging material can reduce the package temperature remarkably to an acceptabl e extent and the entire temperature of package rises with the increasing number of chi ps. Th e design of chi p power has an effect on the package temperature and location of the maximum temperature. Large stress occurs du e to the difference of thermal expansion co efficient between balls and substrates, which may result in the failure of PoP.