TCAD Mobility Model of III-V Short-Channel Double-Gate FETs Including Ballistic Corrections

A TCAD-oriented mobility model, whose main features are: 1) inclusion of ballistic effects in the linear region and 2) smooth transition between the linear and saturation regions, is presented. It is applied to short-channel double-gate thin-body InGaAs MOSFETs. The bases of the model are the concept of ballistic mobility and Matthiessen's rule in the linear regime, and the saturation velocity within a modified Canali model at high-longitudinal fields. Comparisons with accurate semiclassical multivalley multisubband Monte Carlo transport simulations indicate that TCAD simulations making use of the proposed model are able to correctly predict the terminal currents and the internal device quantities in the linear regime in a 15-nm device with no need of fitting parameters. In the saturation region, an empirical adjustment of the saturation velocity is needed, after which currents are accurately predicted for a wide range of gate lengths and bias conditions.