Device modeling of ferroelectric memory field-effect transistor (FeMFET)

A numerical analysis of the electrical characteristics for the ferroelectric memory field-effect transistors (FeMFETs) is presented. Two important structures such as the metal-ferroelectric-insulator-semiconductor field-effect transistor (MFISFET) and metal-ferroelectric-metal-insulator-semiconductor field-effect transistor (MFMISFET) are considered. A new analytic expression for the relation of polarization versus electric field (P-E) is proposed to describe the nonsaturated hysteresis loop of the ferroelectric material. In order to provide a more accurate simulation, we incorporate the combined effects of the nonsaturated polarization of ferroelectric layers and the nonuniform distributions of electric field and charge along the channel. We also discuss the possible nonideal effects due to the fixed charges, charge injection, and short channel. The present theoretical work provides some new design rules for improving the performance of FeMFETs.