An analytical subthreshold swing model to study the scalability limits of double-gate MOSFETs including bulk traps effects

In this work, a physics-based compact subthreshold swing (S) model including bulk traps effects is presented for undoped (or lightly doped) symmetric double-gate (DG) MOSFETs based on an analytical analysis of the two-dimensional (2D) Poisson equation in which the traps effects have been considered. Using this compact model, we have studied the effects of the defects on the scalability limits of DG MOSFETs. We have found that, the scaling capability of DG MOSFET will be improved as the silicon thickness of device is reduced. Compact, explicit expressions of a scale length including bulk trap states are derived, which expedite projections of scalability of DG MOSFETs and its requirement. The analytical results yield good agreement with numerical simulations confirming the model. Our study may provide a theoretical basis and physical insights for DG MOSFET design.