Improved Channel Hot-Carrier Reliability in $p$ -FinFETs With Replacement Metal Gate by a Nitrogen Postdeposition Anneal Process

Channel hot-carrier (CHC) reliability in p-FinFET devices is studied related to the postdeposition anneal (PDA) process. Clearly reduced CHC degradation is observed with N₂-PDA at the V_G = V_D stress condition. The interface defect density degradation calculated from the subthreshold slope is similar in the reference and PDA devices. However, the pre-existing high- k bulk defect is lower in the PDA-treated device as observed by the low-frequency-noise measurement. This leads to less hot/cold-carrier injection into the bulk defects at the high field under the V_G = V_D condition, where a higher charge trapping component is expected than under the classical V_G ~ V_D/2 condition. The responsible bulk defect is pre-existing, not generated during the CHC stress as proven by the stress-induced leakage current analysis.