Review of Nanoscale Vacuum Devices
Xinghui Li, Jinjun Feng
Abstract
The newly developed nanoscale vacuum devices have basic functions similar to traditional vacuum tubes, but can be manufactured by existing silicon-based process lines to achieve small size, light weight, and high integration, which makes them attractive, especially in the recent decade. The historic development and the state-of-the-art of the nanoscale vacuum devices are reviewed. It is found that the devices with lateral, vertical, and gate-all-around structures all have their own advantages and drawbacks. Silicon has the most mature process, but the silicon nanoscale vacuum devices show poor electrical properties and low endurance to harsh conditions when compared with their metal or wide bandgap semiconductor competitors. Even though the most developed nanoscale vacuum devices today still cannot cope with the solid-state devices or integrated circuits (ICs) in most normal applications, they are expected to be first employed in environments with high temperatures or strong radiation.