AbstractQuantum transport properties of negative capacitance transistors (NC-FETs) with monolayer black phosphorus (ML-BP) are theoretically studied. Our calculations show that atomistic thin ML-BP can enhance the amplification effect of the ferroelectric layer, and subthreshold swing is effectively reduced to 27 mV per decade in ML-BP NC-FETs. Device performance can be further improved by increasing the thickness of ferroelectric layer and using thinner or high-k insulate layer. Due to the temperature dependence of ferroelectric layer ML-BP NC-FETs have higher on-state current at low temperature, which is different from that of MOSFETs. By considering the metal–ferroelectric interface layer, our calculations show that the device performance is degraded by the interface. Compared with the International Technology Roadmap (ITRS) 2013 requirements, ML-BP NC-FETs can fulfil the ITRS requirements for high-performance logic with a reduced supply voltage. The new device can achieve very low power delay product per device width at VD=0.3 V, which is just 44% of that in ML-BP FETs.