Nanoscale Vacuum Diode Based on Thermionic Emission for High Temperature Operation.

Zhihua Shen,Shengli Wu,Qiaoning Li,Xiao Wang,Jinshou Tian

doi:10.3390/mi12070729

Abstract

Vacuum diodes, based on field emission mechanisms, demonstrate a superior performance in high-temperature operations compared to solid-state devices. However, when considering low operating voltage and continuous miniaturization, the cathode is usually made into a tip structure and the gap between cathode and anode is reduced to a nanoscale. This greatly increases the difficulty of preparation and makes it difficult to ensure fabrication consistency. Here, a metal-insulator-semiconductor (MIS) structural nanoscale vacuum diode, based on thermionic emission, was numerically studied. The results indicate that this device can operate at a stable level in a wide range of temperatures, at around 600 degrees Kelvin above 260 K at 0.2 V voltage bias. Moreover, unlike the conventional vacuum diodes working in field emission regime where the emission current is extremely sensitive to the gap-width between the cathode and the anode, the emission current of the proposed diode shows a weak correlation to the gap-width. These features make this diode a promising alternative to vacuum electronics for large-scale production and harsh environmental applications.

Highlights

Published: 22 June 2021As a key component of electronic devices, vacuum tubes were first used in extensive applications such as electron emitters, rectifiers, switches and detectors
Vacuum electronics may output with high frequency [2,3], an on/off ratio [4] and a fast temporal response [5]
Vacuum electronic devices are recognized to be more robust in hostile environments, such as those with a high temperature and ionizing radiation [6]

Summary

Introduction

As a key component of electronic devices, vacuum tubes were first used in extensive applications such as electron emitters, rectifiers, switches and detectors. With the continuous demands of low power consumption and miniaturization, vacuum tubes have been replaced by solid-state electronic devices in most of their applications [1]. Vacuum electronics possess intrinsic advantages, as electrons transport ballistically in the vacuum channel while suffering from scattering and collision in solid-state devices. Vacuum electronics may output with high frequency [2,3], an on/off ratio [4] and a fast temporal response [5]. Vacuum electronic devices are recognized to be more robust in hostile environments, such as those with a high temperature and ionizing radiation [6]

Methods

Results

Conclusion