The hot-carrier degradation of deep-submicrometer LDD nMOSFETs under different gate-stress regimes is analysed by means of current-voltage and charge pumping characteristics. Interface state generation is found to arise as the major mechanism responsible for device degradation in the whole range of gate regimes studied. The effects of Short Electron and Hole Injection phases on hot-carrier-stressed devices are also analysed. Although SEI phases are found to be an efficient tool for revealing part of the damage generated in stresses at low gate voltages, the performance of a first SHI phase after stress at high gate bias (Vg>Vd/2) results in a significant additional degradation of the devices. This enhanced degradation is attributed to a sudden interface states build-up occurring near the Si/spacer interface only under the first hot-hole injection condition. Peer reviewed