Effect of depolarization field on steep switching characteristics in negative capacitance field effect transistors

A theoretical model for describing the effect of depolarization field (E-d) in the negative capacitance (NC) field effect transistor (FET) was derived. Based on this model, the electrical properties of the metal-ferroelectric-insulator-semiconductor (MFIS) field effect transistor including the relationship between the depolarizing field and the gate voltage (V-g),E(d)and silicon surface potential, and the drain-source current of NC-FET andV(g)(transfer characteristics) were theoretically investigated. The computing results demonstrated that the surface potential amplification and the steep subthreshold slope characteristics happened at the gate voltage of about 0.4 V, results from the steep increase ofE(d)dependent onV(g)in the NC-FETs. It is expected that the derived results may provide some insight into the design and performance improvement for the NC-MFIS-FET.