Package Design Optimization of Thin Mold Double Side System in Package (DS-SIP)

Currently electrical products such as smart phone and tablet, light weight and thin feature of them are definitely required. To achieve several requirements, size of IC package assembled in limiting space become more crucial and development orientated. Therefore, the Double Side System in package (DS-SIP) with thin mold can meet thin electronic product and also with huge increase in computing functions in a single-structure. However, the complex structure of DS-SIP also brings considerable risks and challenges to the overall package. In generally, in the DS-SIP structure involve filp chip dies and some wire bond dies and a lot of passive components in it. As above mentioned, the DS-SIP with thin mold package will suffer some problems such as warpage and stress in this complex packaging structure. Therefore, how to predict the optimal structural combination in advance via simulation before mass production of DS-SIP with thin mold products is one of the necessary issue.Since the structure of DS-SIP is composed of top and bottom mold and to select suitable compound for top and bottom mold is very important. This paper apply the Ansys software for simulation analysis and to do different compound combination for the DS-SIP package structure. Therefore, to observe the warpage and stress distribution of DS-SIP will confirm package risk level of new devices design. In this paper, there are five kinds of compound for different combinations to observe the best optimized DOE leg for warpage and stressFrom this study, we can conclude some results for improvement warpage and stress performance of DS-SIP with thin mold package structure. The DS-SIP top mold with the low CTE compound and bottom mold with high CTE compound material will obtain well warpage performance. In addition, thin mold DS-SIP structure of the top mold thick than bottom mold can well control warpage.