A study of chip-last embedded FCCSP

Flip-Chip Chip-Scale Packaging (FCCSP) has recently emerged as one of mainstream package solutions due to the superior performance & miniaturization over the wire-bonding technology. There had been lots of efforts to enhance the assembly process efficiency and therefore cost effectiveness. We propose an innovative heterogeneous process integration of the organic substrate and the standard FCCSP assembly process, which is achieved with technical and material improvements; the result is a new type of molding and under-fill technology that has higher process efficiency than conventional “molded under-fill” and demonstrates good warpage control and thermal dissipation. The new process and related package reliability are validated by test vehicle verifications. This “laminated” FCCSP platform is a type of “chip-last embedded die” structure that is extendable to support stackable packages for use in advanced package-on-package (PoP) applications.