The abnormal electrostatic discharge of a no-connect metal cover in a ceramic packaging device

The human body model (HBM) stress of a no-connect metal cover is tested to obtain the characteristics of abnormal electrostatic discharge, including current waveforms and peak current under varied stress voltage and device failure voltage. A new discharge model called the ''sparkover-induced model'' is proposed based on the results. Then, failure mechanism analysis and model simulation are performed to prove that the transient peak current caused by a sparkover of low arc impedance will result in the devices' premature damage when the potential difference between the no-connect metal cover and the chip exceeds the threshold voltage of sparkover. (semiconductor devices)