Assessment on Reliability of 1.0mm pitch BGA Package double-side assembly

The article consists of a Powerpoint presentation on reliability of 1.0 mm pitch BGA package double-side assembly. The paper concludes that the for PCBA structure using in ATC experiments, we found: 1. for all groups, the first crack will initialize from solder joints of corner; 2. for SnAgCu alloy, double side mirror will reduce life by over 3 times compared with single-side whether by using experiment or FEM; while for SnPb alloy, FEM analysis show the reduction degree will increase more; 3. Double side offset assembly shape will increase the solder joints reliability to some extent compared with mirror. Reasons of solder joints reliability reduction for BGA double-side assembly maybe include package structure, solder alloy, PCB thickness, offset distance, and so on, these factors will interact.