The influence of micro/nano-structure on transmission ability of low-energy Electron Transmission Window

Abstract

It is a extremely difficult to make the Electron Transmission Window (ETW) have the transmission ability for low-energy electrons, excellent mechanical strength, and thicker thickness at a large barometric pressure gradient, i.e., from vacuum to atmosphere. We present a new physical model of the ETW, which has a periodic array microstructure to restrain the temperature increase and nanostructures to provide transmission channels for electron sources. Two different periodic array micro-pattern ETWs with nanostructures have been prepared to testify the physical mechanisms, which are a thicker periodic array triangle micro-pattern unit with a nested triangle pillar type (NETW) and a thinner one without nested part type (OETW). A nanosecond-pulse power source and an array field emission electrode are adopted to focus the energy and reduce the energy dissipation of the electron source. The transmission efficiencies of the NETW and the OETW are 5.86% and 2.82% at −3.5 kV, 8.90% and 5.77% at −5.5 kV, and 12.69% and 11.97% at −8.5 kV pulsed voltages, respectively. In addition, the transmission abilities of the two ETWs have been compared by visualization diagnoses in transient and steady states, which match well with the results of transmission efficiencies. It is found that the results are consistent with those of this novel model mechanism.