Negative capacitance transistors with monolayer black phosphorus

Quantum 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 V-D = 0.3 V, which is just 44% of that in ML-BP FETs.