Evaluating the Drift-Region Length Effect of nLDMOS on ESD Ability with a TLP Testing System

In this work, the effect of different drift region lengths on the ESD ability in ultra-high voltage LDMOS is proposed and verified via a 0.5 μm 300 V process. By the different drift-region lengths, the corresponding breakdown voltage can result in the corresponding trigger voltage, holding voltage and secondary breakdown current. As the drift-region length decreases, V
_t1
and V
_h
values will decrease both too. Eventually, as the drift-region length is 5.8 μm, the optimized secondary breakdown current can be upgraded to 6.842 A. The overall DUTs has higher ESD ability than that of the reference group.