HOT-CARRIER DEGRADATION OF THE RANDOM TELEGRAPH SIGNAL AMPLITUDE IN SUBMICROMETER SI MOSTS

This paper studies the Hot-Carrier (HC) degradation of submicrometer S i MOSTs by the changes in the Random Telegraph Signal (RTS) parameters . It is demonstrated that the amplitude of a pre-existing RTS is marke dly changed after stress. In linear operation, a reduction is generall y observed for n-MOSTs, while an increase is found for p-MOSTs. For la rger drain voltages, the changes are most pronounced in reverse operat ion, i.e. with source and drain switched, for a forward stress. Hence, the trap-amplitude asymmetry increases after stress. As is demonstrat ed, there exists a close correlation between the observed changes in t he RTS amplitude and in the static device parameters. A simple, first- order model is derived, showing that the HC stress-induced reduction ( n-channel), or increase (p-channel) is proportional to the variation o f the oxide/interface charge density near the drain. Alternatively, it is demonstrated that the normalized change in the RTS amplitude is eq ual to the normalized conductance change of the narrow hot-carrier dam aged region.