Limitations of the modified shift-and-ratio technique for extraction of the bias dependence of L/sub eff/ and R/sub sd/ of LDD MOSFETs

The purpose of this study, based on two-dimensional (2-D) simulation, was to scale effective channel length and series resistance extraction routines for sub-100 nm CMOS devices. We demonstrate that L/sub eff/- and R/sub sd/-gate-bias dependence extracted using a modified shift-and-ratio (M-S&R) method may not give accurate results because of a nonnegligible effective mobility dependence on gate bias. Using a reasonable gate bias-dependent mobility model, one observes a finite V/sub g/ dependence of L/sub eff/ and R/sub sd/ even for devices with degenerately doped drain junction.