ab initio simulation on mono-layer MoS2 tunnel FET: Impact of metal contact configuration and defect assisted tunneling

We have investigated the performance of the mono-layer MoS
₂
tunnel FET (TFET) through quantum transport simulations based on density functional theory (DFT). Two kinds of source/drain metal contact configurations namely the seamless contact and side contact are compared. It was found that ideal band bending control by seamless contact yields much better performance than the side contact, although the device performance is still far from the ITRS expectations of the future high performance (HP) and low power (LP) transistors. In the meanwhile, introduction of mid-gap defects near source channel interface was found to be effective performance booster. Such MoS
₂
TFET with Mo vacancy defects was found to outperform the ITRS HP requirement.