Negative differential resistance (NDR) based on the band-to-band tunneling (BTBT) mechanism has recently shown great potential in improving the performance of various electronic devices. However, the applicability of conventional BTBT-based NDR devices is restricted by their insufficient performance due to the limitations of the NDR mechanism. In this study, we develop an insulator-to-metal phase transition (IMT)-based NDR device that exploits the abrupt resistive switching of vanadium dioxide (VO2) to achieve a high peak-to-valley current ratio (PVCR) and peak current density (Jpeak) as well as controllable peak and valley voltages (Vpeak/valley). When a phase transition is induced in VO2, the effective voltage bias on the two-dimensional channel is decreased by the reduction in the VO2 resistance. Accordingly, the effective voltage adjustment induced by the IMT results in an abrupt NDR. This NDR mechanism based on the abrupt IMT results in a maximum PVCR of 71.1 through its gate voltage and VO2 threshold voltage tunability characteristics. Moreover, Vpeak/valley is easily modulated by controlling the length of VO2. In addition, a maximum Jpeak of 1.6 × 106 A/m2 is achieved through light-tunable characteristics. The proposed IMT-based NDR device is expected to contribute to the development of various NDR devices for next-generation electronics.
Keywords: insulator-to-metal transition; negative differential resistance; peak current density; peak-to-valley current ratio; vanadium dioxide.