Predictive physics based simulation of nano scale gate-all-around field effect transistor under the influence of high-k gate dielectrics

In this paper the electrical characteristics of a nano scale silicon gate-all-around field effect transistor (GAA-FET) with different dielectrics in the gate electrode are predicted. For this, we first calibrate physics based TCAD simulator against experimental results reported by IBM. Then the device electrical figures of merit comprised of ION/IOFF, transconductance (gm) and subthreshold slope (SS) are extracted. The obtained results show that utilizing various high-k gate dielectrics has a noticeable impact on the device performance. Different high-k gate dielectrics comprised of Al2O3, Si3N4 and HfO2 are explored in our study. Moreover, when high-k gate dielectric is used instead of conventional SiO2 insulator, the electrical characteristics will be improved in terms of ION/IOFF ratio, transconductance to drive current ratio (gm/IDS) and SS. Based on our simulations and obtained results, scaling GAA-FETs by utilizing high-k dielectrics offers superior electronic devices and promising candidates for “more Moore” domain and integrated circuit applications.