Three-Dimensional Cold Metals in Realizing Steep-Slope Transistors Based on Monolayer MoS2

Three-dimensional cold metals are explored and applied as a cold source (CS) contact in monolayer (ML) MoS2 FETs to realize sub-60 mV/dec switching. We comprehensively studied the electronic properties of six kinds of cold-metals, cold-metal semiconductor contacts, and the device performance of MoS2 CSFETs by first-principles quantum transport simulations. These cold-metals possess an intrinsic energy gap above the Fermi level and can filter high-energy electrons as a cold electron source. The contact resistances between cold metals and ML-MoS2 are calculated and can be reduced by appropriate doping for high injection currents. Device simulations show that an average subthreshold swing of 20 mV/dec in over five-decades of current and an on-state current over 5.7x10(2)mu A/mu m can be achieved in MoS2 CSFETs with cold-metal contacts at V-D = 0.5 V and I-off = 10(-4) mu A/mu m . The simulated device performance of MoS2 CSFETs can meet the requirements of IRDS with significantly reduced power dissipation.

Automated summary

In this study, we explored 3D cold metals as cold source contacts in MoS2 FETs and achieved sub-60 mV/dec switching. We found that cold metals possess an intrinsic energy gap above the Fermi level and can filter high-energy electrons. By appropriate doping, the contact resistances can be reduced, and the device performance of MoS2 FETs can meet the requirements of IRDS with significantly reduced power dissipation.