On the experimental determination of channel back-scattering in nanoMOSFETs

By using accurate Multi-Subband-Monte-Carlo simulations of quasi-ballistic transport we carry out a detailed re-examination of the experimental extraction procedure for the ballistic-ratio BR=ID/IBAL in nanoMOSFETs proposed in [1]. It is found that the ballistic-ratio extracted applying this procedure to the simulated drain current severely underestimates the BR extracted by directly compare the simulated ID and IBAL. This is mainly due to inaccurate determination of the temperature dependence of the inversion charge. It is suggested that this limitation of the extraction procedure may explain the apparent lack of improvement in the ballisticity with the geometrical scaling.