Bias-HAST on tape ball grid array (TBGA) test pattern

Tape ball grid array (TBGA) rather than the traditional BGA, can provide a more flexible, light weight and fine pitch interconnection method to the electronic industry. In this study, two different designs of TBGA, buss-out and buss-in, were used thought-out this investigation. Moreover, for those samples were then further sub-divided, one with hot deionized (DI) rinsing after solder resist development and gold plating; while the other matrix samples, no hot DI rinsing were applied. It was found that metallic elements were found after 168 h of Highly Accelerated Stress Testing (HAST). Moreover, result from the cross-section indicated that crack was found in the solder resist and both white and bronze powdery were found. With further elementary analysis of those different colors of powdery, tin and lead in white powdery were found, while tin, lead and copper were found in the bronze powdery. The tin, lead and copper dendrite then will cause short circuit of the package. 2003 Elsevier Ltd. All rights reserved.