Moisture sensitivity evaluation of ball grid array packages

Abstract

Ball Grid Array (BGA) packages have been gaining popularity due to the increasing demand for greater interconnect density. For high I/O applications, plastic BGA (PBGA) and tape BGA (TBGA) are attractive alternatives to fine-pitch quad flat pack and pin grid array packages because of their relative low cost, ease of surface mount assembly, and smaller board space requirement. However, since PBGA and TBGA are non-hermetic packages, they are vulnerable to moisture-induced damage during the surface mount assembly process. An evaluation was performed to investigate the impact of moisture on package delamination and cracking during the solder reflow process and the reliability of PBGA and TBGA packages. Based on our study using scanning acoustic microscopy and reliability stress tests, both PBGA and TBGA can be safely surface mounted if proper storage and handling guidelines are followed.