CAE Simulation and Verification of Wire Sweep for BGA 436

Abstract

The microelectronics industry continues to grow rapidly in size and importance. As thinner and denser IC packages become, packaging process becomes more challenging and troublesome. The ball grid array (BGA) technology uses substrate and solder balls to replace the traditional leadframe, which offers many advantages over fine pitch technology. These include better assembly yield, superior electrical performance, and higher I/O density. However, the high density of bonding wires form a separating layer which will hold back the molding compound flowing through these regions. The paper presents the simulation of melt-front advancement and wire sweep for BGA 436. The results has been verified by the experimental studies. It is found that the high-density of wires has played a very important role in performing the CAE analysis. It shows that the melt-front advancement can be precisely predicted by CAE simulation software with proper consideration of wire density. With the accurate simulation of melt-front advancement, the CAE results can be further used to perform further engineering analysis. The wire sweep of the package demonstrates the use of CAE analysis, which also shows very good agreement with the experimental study.