Challenges in packaging a 4 chip FC MCM-L using KGD

Abstract

The FC MCM-L (Flip Chip MultiChip Module on Laminate) product is comprised of four Known Good Die (KGD) on 25/spl times/25 mm laminate substrate with solder clad bond pads. The FC MCM-L package was similar to that of single chip flip chip on laminate product with respect to assembly processing and material set. However, differences related to KGD, and the close proximity of die with minimal substrate real estate provided opportunities for process improvement. This paper describes the manufacturing processes and challenges encountered in the chip attach and underfill encapsulation processes. Finally, the MCM test and reliability results are discussed.