Threshold voltage roll-off model for low power bulk accumulation MOSFETs

A closed-form analytical threshold voltage roll-off model (/spl Delta/V/sub T/) for bulk accumulation MOSFETs, namely, buried channel accumulation (BCA) and surface channel accumulation (SCA), has been derived. Results show that scaling of BCA/SCA devices to the L=0.1 /spl mu/m range while maintaining performance is feasible for devices with very shallow tubs and source/drain junctions. It is also observed that for such devices, the SGA /spl Delta/V/sub T/ can be substantially smaller than the conventional surface channel inversion MOSFET /spl Delta/V/sub T/.