High reliability, high density, low cost packaging systems for matrix BGA and CSP using VPES (vacuum printing encapsulation systems)

BGA and CSP package markets are increasing in the world. In general, transfer molding systems are used for these packaging processes. But transfer molding systems are difficult to change for highly expensive metal die. One advantage of transfer molding systems is their good dimensional accuracy. This paper describes a unique method-Vacuum Printing Encapsulation Systems (VPES)-we developed to solve such problems, at a lower cost than for transfer molding. We used matrix type BGA and CSP for this test. Matrix type BGA and CSP make printing technology easy to use at die-bonding, packaging, marking, and flux coating steps in the process. Total cost of these packages is lower than for the transfer molding process. We developed a very low warpage and high reliability epoxy resin for use with matrix BGA and CSP. Matrix BGA and CSP need more weight of epoxy resin than individual BGA and CSP, and there can be very great warpage after curing. We achieved high reliability and low cost packaging systems with this technology