Experimental Investigation of Effect of Channel Doping Concentration on Random Telegraph Signal Noise

Random telegraph signal (RTS) noise has become one of the most important problems in the continuous scaling down of field-effect transistors (FETs). In this study, we investigate experimentally the relationship between RTS amplitude and channel doping concentration (N A), which is a key parameter related to threshold voltage adjustment and short-channel effects, in 393,216 n-type FETs by a high-speed measurement method. We demonstrate that N A has a significant effect on RTS amplitude even at approximately the same interface and bulk trap densities of the gate insulator films, which are evaluated by the charge pumping method, by the quasi-static capacitance–voltage method, and on the basis of 1/f noise characteristics. An increase in RTS amplitude may arise from a more advanced channel nonuniformity as N A increases.