RELIABILITY OF FLIP CHIP PACKAGE DEPENDING ON UNDERFILL ENCAPSULATING PROCESSES

摘要

Recently, we found a guideline to grasp the relationship between generated stresses, strain at any interface in a flip chip (F/C) package and warpage. Additionally, we found a possibility that generated stress and strain at any interface could be controlled by assembly process up to encapsulating even if same package was used. In the present paper, in order to understand the further details of the mechanism of package deformation, we investigate difference in warpage dependent on the encapsulation processes of capillary underfill (CUF) and no flow underfill (NUF), using same material as underfill (UF) and same F/C package structure. And we discuss package warpage and reliability dependent on encapsulation processes.