Resistive-Gate Field-Effect Transistor: A Novel Steep-Slope Device Based on a Metal—Insulator—Metal—Oxide Gate Stack

A novel silicon-based resistive-gate field-effect transistor (ReFET) with metal-insulator-metal-oxide gate stack is proposed. With the abrupt resistance change event from high-resistance state to low-resistance state in the introduced insulator layer, the threshold voltage of ReFET can be suddenly decreased, resulting in an abrupt switching of drain current. The device is capable of sub-60-mV/decade subthreshold slope (SS), as well as MOSFET-comparable ON-current. The fabricated n-type ReFET device with Pt/TiN/TaO_x/Poly-Si/SiO₂ gate stack can achieve steep SS of 8 mV/decade. With future materials and threshold voltage optimization, high I_ON/I_OFF ratio with reduced operation voltage can be expected, which shows that ReFET is a promising candidate for ultralow power applications.