High-efficiency secondary-electron emission from sputtered MgO–Au cermets

Abstract

We have obtained high‐efficiency secondary‐electron emission from a new sputtered cermet system, MgO–Au. Peak yields of 8 and quantum gain for primary‐electron energies as low as 17 eV have been achieved on thick films without the presence of surface charging. The very small insulator particle sizes (< 50 Å) in the films permit removal of surface charge by tunneling to adjacent metallic regions. This type of emitter is potentially useful for secondary‐emitting cathodes in high‐power device applications as well as low‐power electron multiplication.