Compact Quantum Modeling Framework for Nanoscale Double-Gate MOSFET

A quantum mechanical modeling framework for ultrathin body (UTB) device operating in the subthreshold and near-threshold regime is presented. For subthreshold conditions, we have assumed that the electrostatics is dominated by capacitive coupling between the body electrodes. Hence, the charge is neglected in Poisson equation, thus decoupling the quantum effects and electrostatics in the body. The potential is obtained as a solution of the 2D Laplace equation with the help of conformal mapping techniques. In the near-threshold regime, we have solved Poisson’s equation using the quantum charge density along the gate-to-gate symmetry line to calculate the total potential. We find that the classical approach underestimates the total potential inside the device body. Finally, the current in subthreshold is modeled assuming drift-diffusion transport with electron density calculated quantum mechanically.