Investigation on the Root Cause of ESD Failure of Large Size WBBGA Package Chip

In this paper, the root causes of electrostatic discharge (ESD) problems in large size wire bonding ball grid array (WBBGA) package chips are investigated, and two aspects of failure are confirmed. One is related to the test process. The 1-V curve test process is not standardized, resulting in damage to the internal circuit function of the chip. The second is related to design defects. The open/short (O/S) failure is caused by the weak connection point at the pad, and the leakage failure is caused by the insufficient number of power clamps. Hot spot localization analysis provides favorable evidence. The results of this paper provide guidance for the modification and strengthening of ESD protection design, and standardize the ESD testing process, effectively avoiding the recurrence of such ESD failures.