ViperBGA: a novel design approach to high performance and high density BGA's

Abstract

Clock speed requirements will approach 500 MHz and above and thermal requirements of packages will be over 15 watts by the turn of the century as predicted by SIA and electronic industry analysts. The PDA, laptop markets and the cellular markets are increasingly demanding smaller footprint and low cost packaging. ProLinx's ViperBGA with its patented MicroFilled Via technology has been successful in meeting the above market demands. The ViperBGA exhibits a high electrical performance and a high thermal performance at a considerable cost savings compared to current high performance substrates. These enhancements are further optimized by proper use of 3D field solvers as well as extensive use of finite element modeling and the EGA substrate's thermal and electrical parasitics measurements. This paper will discuss a methodology in which modeling combined with ProLinx's BGA designer software is effectively used to optimize the layout of the EGA substrate for high density interconnect routing and optimal placement of electrical and thermal vias for performance enhancements before the manufacturing of the substrates. Measurements are performed after the substrate has been manufactured, and correlated with modeling. Modeling and measurements are done on both the two layer and three layer, cavity down and cavity up substrates.