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 I_dlin 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 I_dlin and I_dsat for their different current distributions.