Switching kinetics of interface states in deep submicrometre SOI n-MOSFETs

Switching kinetics characteristics of interface traps in deep-submicrometre SOI n-MOSFETs have been investigated by random telegraph signals (RTSs). T wo different types of behaviour of noising centres, Coulomb-attractive and Coulomb-repulsive centres, have been observed. By studying the gate bias an d temperature dependence of the transition rime and amplitude of the RTSs c aused by the noising centres, it has been demonstrated experimentally that a thermally activated process may dominate for Coulomb-repulsive centres, w hile quantum mechanical tunnelling is a favoured process for Coulomb-attrac tive centres. In particular, RTSs with very large amplitude (>60%), which a re almost independent of measurement temperature and gate bias, are observe d in an ultra-narrow channel, which is well described by the quantum tunnel ling model.