Highly Tunable Negative Differential Resistance Device Based on Insulator-to-Metal Phase Transition of Vanadium Dioxide.

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 (VO 2 ) to achieve a high peak-to-valley current ratio (PVCR) and peak current density ( J peak ) as well as controllable peak and valley voltages ( V peak/valley ). When a phase transition is induced in VO 2 , the effective voltage bias on the two-dimensional channel is decreased by the reduction in the VO 2 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 VO 2 threshold voltage tunability characteristics. Moreover, V peak/valley is easily modulated by controlling the length of VO 2 . In addition, a maximum J peak of 1.6 × 10 6 A/m 2 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.