Printing encapsulation systems (PES) of advanced multichip module and COB device

摘要

Continuous study of a printing encapsulation system (PES) for multichip module and COB (chip on board) led to optimal encapsulation resin properties. The authors have developed a printing encapsulation system (PES) of high reliability and quality, free of voids, and a thin and desirable encapsulation resin shape for an advanced COB device. Using this PES, it was possible to solve the problems in the printing encapsulation process to keep control of resin viscosity and other properties at open lid storage. It was possible to determine the suitable thixotropic property index. The authors developed a void-free process system which avoids the effects of heat shock and achieves moisture resistance improvement, and a short time curing system.