Layered structures with delta-doped layers for enhancement of field emission

Abstract

The electron field emission, from silicon tip arrays with layer structures on their surfaces, was investigated. The main task of the study was to enhance field emission. The n–Si–SiO2, n–Si–Cs–SiO2,n–Si–SiO2–Si*–SiO2,n–Si–Si3N4–Si*–SiO2, etc., were among the different prepared layered structures. The thicknesses of dielectric layers were 1–5 nm and they were prepared both by thermal oxidation and by chemical vapor deposition (CVD). The cesium was deposited on the cathodes with the application of cesium salt (CsCl) in solution. The outer SiO2 layer prevents cesium from evaporating during heating or reaction under exposure to gases. The thin silicon layer (Si*) was formed by CVD. The measurements of electron field emission from layered structures show sufficient enhancement of emission in the case of using the delta-doped cesium layer. The incorporation of cesium is an important way to decrease the threshold voltage of cold cathodes, and in our case the use of a SiO2 layer allows us to stabilize the emission.