Using design of experiment simulation responses to predict thermal performance limits of the heatsink small outline package (HSOP) considering both die bond and heatsink solder voiding

This study provides a method to predict the steady state natural convection thermal performance limits of a heatsink small outline package (HSOP) when mounted on either an aluminum/polyimide or FR4 printed circuit board. Analysis variables include the die area, power dissipation, die bond voiding, and package heatsink solder voiding. A 20-lead HSOP (20HSOP) was chosen for demonstration purposes. The methodology discussed herein can be easily applied to evaluate the thermal performance limits of other microelectronic packages. The method chosen to perform the analysis was a central composite design of experiments (CCD). An experimentally validated finite element analysis (FEA) model was used to predict θ_ja and ψ_jc values for a series of twenty-five CCD simulations which encompassed the favored design space of the 20HSOP. The FEA model utilized a temperature dependent heat transfer coefficient which accounted for both natural convection and radiation heat transfer. The end product is a set of polynomial equations which allow the user to quickly predict the thermal capability of the package under various configurations