Dirac Electrons at the Source: Breaking the 60-mV/Decade Switching Limit

Abstract

Power consumption of today’s integrated circuit is very difficult to reduce because the MOSFET is subjected to the thermal limit of 60 mV/decade for the subthreshold swing (SS). In this paper, we show that this SS limit of thermionic current can be conquered—thus power consumption drastically reduced by density of states (DOS) engineering at the source. Specifically, the linear DOS of Dirac electrons at the source concomitant with an efficient gate control brings the SS limit down to 37 mV/decade, and further down to very small values by suppressing the thermal tail contribution with a small bandgap in the injected DOS. Using the first principles analysis, we demonstrate that FETs with Dirac source to possess extremely promising device performance in both energy dynamic power and switching speed at the ultralow operating voltage regime of 0.3 V compared with ultrathin-body Si FETs.