Compact Drain Current Model of Silicon-Nanotubebased Double Gate-All-Around (DGAA) MOSFETs Incorporating Short Channel Effects

This paper reports a compact drain current model of silicon nanotube-based double gate all around (DGAA) MOSFET incorporating short channel effects (SCEs). The drain current equation is expressed as a function of charge density, which is derived using the unified surface potential expressions. Fermi-Dirac statistics, the 1-dimensional density of states and Gauss's law have been utilized to develop the analytical expressions of unified surface potentials and charge density. The proposed compact model also takes into account of quantum confinement effects which is significant in devices with the ultra-thin channel region. The SCEs such as velocity saturation effect, threshold voltage roll-off, DIBL, channel length modulation, velocity overshoot, and mobility degradation are well incorporated in the developed model in order to correctly predict the device output and transfer characteristics. Results obtained from the proposed compact drain current model have been validated with TCAD results obtained from the Sentauras device simulator.