Quantum simulation study of gate-all-around (GAA) silicon nanowire transistor and double gate metal oxide semiconductor field effect transistor (DG MOSFET)

In this paper, electrical characteristics of the double gate metal oxide semiconductor field effect transistor (DG MOSFET) and that of gate all around silicon nanowire transistor (GAA SNWT) have been investigated. We have evaluated the variations of the threshold voltage, the subthreshold slope, draininduced barrier lowering, ON and OFF state currents when channel length decreases. Quantum mechanical transport approach based on non-equilibrium Green’s function method (NEGF) has been performed in the frame work of effective mass theory with taking into account exchange-correlation effects. Its simulation consists of solutions of the three dimensional Poisson’s equation, two dimensional Schrodinger equation on the cross section plane, and also transport equation. We have shown that for lengths smaller than 15 nm, short channel effects dominate. When the dimensions become smaller, interelectronic distance decreases and the interaction between electrons and also exchange correlation effects increase. We have also demonstrated that short channel effects are decreased using the device which has a good control of gate.