A Vertical Top-Gate Multichannel Vacuum Triode With Low Subthreshold Swing

A vertical top-gate multichannel vacuum triode (TG-MVT) with a 50-nm channel size is proposed and fabricated using IC-compatible manufacturing techniques. By employing a unique multichannel gate-surrounding structure, a low subthreshold swing (SS) of 58.9 mV/dec is achieved. In addition, the proposed TG-MVT device exhibits a low turn-on voltage of 0.6 V and achieves a high emission current of 20 —A with a large current on/off ratio of 8e⁴ at 1.8 V drain voltage. The role of the top-gate surrounding structure in field emission tunneling and the electron transport mechanism is clarified through the theoretical analysis. Meanwhile, a theoretical scheme for the design optimization of the device toward nanoscale miniaturization is presented. This article provides a novel technical approach for the development of low-power and high-performance nanoscale channel vacuum electronic devices.