Impact of Solder Overflow and ACLV Moisture Absorption of Mold Compound on Package Reliability

Moisture induced die surface metal layer corrosion is a critical reliability problem which may cause eletrical failures. In this paper, the impact of solder overflow and moisture absorption of mold compound on the die surface metal layer are investigated through modeling work. Comprehensive analysis of the modeling and simulation results for die surface metal layer moisture concentration is presented. The assembly process is optimized to reduce solder overflow after the modeling. Practical tests of the solder overflow and moisture absorption factors of mold compound are carried out. Both modeling and testing have confirmed that solder overflow and mold compound´s moisture absorption have a significant impact to die surface metal layer´s moisture concentration.