Precise 2D Compact Modeling of Nanoscale DG MOSFETs Based on Conformal Mapping Techniques

We present a new technique for 2D compact modeling of short-channel, nanoscale DG MOSFETs. In low-doped devices working in the subthreshold regime, the potential distribution is dominated by the capacitive coupling between the body contacts. This 2D potential is determined by a solution of the Laplace equation for the body using the technique of conformal mapping. Near threshold, where the spatial inversion charge becomes important, a self-consistent solution is applied for the important region around the barrier maximum. In sufficiently strong inversion, the electronic charge will dominate the potential profile in central parts of the channel. For this case, an analytical solution of the 1D Poisson's equation is used. Based on the barrier profiles the drain current was calculated for both drift-diffusion and ballistic transport. The results compare favorably with numerical simulations.