A novel technique to determine the gate and drain bias dependent series resistance in drain engineered MOSFETs using one single device

A new measurement method is explained for the extraction of the source and drain series resistance of drain engineered MOSFETs from their low frequency ac characteristics as a function of gate and drain bias using only one single MOSFET. Experimental results indicate, the effect of drain voltage dependent series resistance is relevant both in the ohmic and in the saturation region of the MOSFET. In addition the new measurement method is extended in such a way that it can be used to measure the series resistance as a function of gate bias only at low drain bias. Comparison of this single transistor measurement technique with other methods, needing a set of identical transistors with different channel lengths, shows that our method gives equal results. Finally attention is also given to the modeling of the series resistance in the ohmic and saturation region. For both regions simple, accurate compact model expressions have been derived.