Recovery after hot-carrier injection: Slow versus fast traps

Long-channel nMOSFETs have been electrically degraded by hot-carrier injection and the recovery at a temperature of T = 85 degrees C in air has been investigated. Charge-pumping measurements have been performed in combination of IV measurements to distinguish between interface defects, deeper defects and charge detrapping. The recovery rate of Delta V-t is increased by a temperature step (presumably due to charge detrapping), however the recovery of the charge pumping current seems to follow the universal relaxation curve used for BTI at T = 85 degrees C, regardless of the stress temperature of the device. The recovery of the charge pumping current is mainly attributed to the repassivation of fast interface defects and deeper (border) traps may also play a (smaller) role in the recovery phase.