Numerical Analysis Study of The Effects of Backscattering Coefficient on Electrical Performance of Double-Gate nano-MOSFET

Abstract

The simulated and computed electrical characteristics, with and without carriers backscattering, of 10 nm double-gate (DG) nano-MOSFET have been investigated and compared in this paper. The electrical parameters thus studied include Ballistic Enhancement Factor (BEF), on-state ballistic drain current Id, 2D electron density Qi and electron velocity v. BEF values with and without backscattering coefficients are 2.065 and 2.149, respectively because injection velocity reduced when considering backscattering. Average electron velocity near the beginning of the device channel has been found to reduce from 4.131x105 ms-1 to 1.186x105 ms-1 with the inclusion of backscattering phenomenon. The 2D electron density with and without backscattering coefficient are 3.927x1016 m-2 and 3.850x1016 m-2, respectively. The increment is because backscattered electrons and injected electrons superimposed and interfered with each other in the channel due to wave nature of electrons occurance in nanometer transistors. There are two current equations studied in this paper. The first one is based on flux-theory and the other one based on the product of electron concentration and electron velocity. The first method showed a current reduction from 2.548x103 μA/μm to 2.497x103 μA/μm. The second way also approximately showed reduction from 2.548x103 μA/μm to 2.497x103 μA/μm after minor modification in modeling. Both ways indicated that electrons are backscattered to the source by the potential barrier at the beginning of the channel and thereby reduced the number of electrons reaching the drain. In conclusion, backscattering is a physical phenomenon which can’t be ignored in describing electron transport in DG nano-MOSFETs.