Investigation on Hot-carrier-induced Degradation for the n-type Lateral DMOS with Floating p-top Layer

The hot-carrier-induced degradation for the n-type lateral DMOS (nLDMOS) with floating p-top layer has been experimentally investigated for the first time. Our experiments show that the degradation of the linear drain current (I-dlin) has a strange shift at the beginning of the stress. The studies demonstrate that the strange shift comes from the unexpected depletion of the p-top layer. Moreover, it is noted that the corrected saturation drain current (I-dsat) degradation has a turnover at stressing 100s while the degradation of Idlin has not. Further studies illustrate that the different degradation phenomenon comes from different influence mechanisms of generated interface states and injected hot holes on the Idlin and I-dsat for their different current distributions.