Anomalous geometry dependence of source/drain resistance in narrow-width MOSFETs

The geometrical scaling of the intrinsic source/drain series resistance of MOSFETs is investigated using a large selection of transistor geometries in 0.5 /spl mu/m CMOS technology. It is shown both experimentally and theoretically that for narrow-width MOSFETs with dog-bone layouts, the source/drain resistance is no longer inversely proportional to the channel width. A new scaling rule for the source/drain resistance and thus for the mobility reduction parameter /spl theta//sub 1/ of MOS Model 9 leads to a considerably improved modelling accuracy in both the linear and saturation regimes.