CHANGE IN DC AND L F NOISE CHARACTERISTICS OF N-SUBMICRON MOSFETS DUETO HOT-CARRIER DEGRADATION/

Hot-carrier stress and its influence on d.c. and 1/f noise characteris tics in submicron n-channel MOSFETs was investigated. From a 0.5 mu m CMOS technology we observed a negative shift in the threshold voltage and a decrease in the drain current. The degradation increases the ser ies resistance on the drain side. In most cases, the relative 1/f nois e in the drain current also increases. A degraded device is often foun d to be noisier in its reverse mode than in its normal mode. The novel material is that the normalized 1/f noise analysis in terms of the 1/ f noise parameter a is a more sensitive diagnostic tool for hot-carrie r degradation in submicron MOSFETs than S-I (A(2)/Hz) and some results are qualitatively explained in terms of mobility fluctuations. (C) 19 98 Published by Elsevier Science Ltd.