IDENTIFICATION OF ISOLATION-EDGE RELATED RANDOM TELEGRAPH SIGNALS IN SUBMICRON SILICON METAL-OXIDE-SEMICONDUCTOR FIELD-EFFECT TRANSISTORS

In this letter, evidence is given for a new class of random telegraph signals (RTSs) in submicron n-metal-oxide-semiconductor field-effect t ransistors (n-MOSFETs). These two-level fluctuations not only occur wh en the MOSFET is biased in linear operation but also when it is operat ed in the source or drain-substrate diode mode. A detailed investigati on of the RTS parameters. i.e., the amplitude, the emission, and the c apture time constants, reveal a close correlation with the current thr ough the forward biased drain- (or source-) substrate diode. At the sa me time, from the substrate bias dependence of the trap characteristic s, it is inferred that it behaves like a near-interface oxide trap. Fr om this, it is concluded that the most likely position is along the ch annel width perimeter, at the isolation edges of the transistors and c lose to the source or drain junction. (C) 1997 Academic Institute of P hysics.