Modeling the effects of the channel electron velocity on the channel surface potential of ballistic MOSFETs

After the coupling between the longitudinal and transverse components of channel electron motion is considered, the coupled Schrödinger–Poisson equations have been self-consistently solved. The results demonstrate that channel electron velocity can largely affect the channel surface potential of nanometer n-MOSFET once the ballistic transport ensures the velocity higher than 1 × 107 cm/s. Self-consistent calculations clearly illustrate that a larger channel electron velocity leads to a larger change in the channel surface potential. In addition, the relative change in the channel surface potential caused by such a coupling depends on both acceptor concentration and gate voltage. These results suggest that such a coupling should be considered in the channel surface potential model of nanometer n-MOSFET when the ballistic transport ensures the velocity higher than 1 × 107 cm/s.