A new quasi-3D analytical framework for channel potential and threshold voltage in triple material gate nanosheet MOSFETs

Nanosheet MOSFETs is an excellent replacement for FinFETs for sub-5 nm technology nodes because of their outstanding electrostatic control provided by their gate-all-around structure. A novel Triple Material Gate nanosheet MOSFETs is presented in this work. For the first time, an analytical model for the threshold voltage and channel potential is derived using a quasi-3D approach. Through consideration of both vertical and a lateral potential fluctuation, the proposed model effectively depicts electrostatic behavior. Ballistic transport theory is utilized to assess subthreshold swing and threshold voltage characteristics, improving the accuracy of predictions. The results demonstrate an 11.3 % drop in subthreshold swing and a 10 % reduction in threshold voltage, assuring improved device performance. The proposed TMG-NS-MOSFETs achieve a high current ON and OFF ratio of 2.4 × 10⁶ at 20 nm gate length, ensuring excellent switching performance. A significant correlation is confirmed via validation against TCAD simulations, proving the model's dependability. This novel analytical approach advances the modeling of semiconductor devices by offering better insights into nanosheet MOSFETs electrostatics. Based on the results, new nanosheet MOSFETs designs can be incorporated into ultra-low power, high performance microelectronic circuits of the future.