Secondary Electron Emission Properties From Boron Doped Diamond Films

The cathode materials used in electron multiplier, field emission cathode and particle/photon detector have the problem of low secondary electron emission yield and unstable emission. To solve this problem, different boron concentration diamond films by microwave plasma chemical vapor deposition were prepared. The surface of B-doped diamond film was treated by Hydrogen plasma. The secondary electron emission (SEE) from B-doped diamond films was investigated. The scanning electron microscopy (SEM) and the Raman spectrum analysis were used to examine the properties of the B-doped diamond film. The maximum SEE yield up to 18.3 at 1 keV primary beam energy was found under the condition that the samples were left in air for weeks and subject to no treatment prior to the measurement. Oxidation treatment destroys negative electron affinity (NEA) whereas heating up in vacuum substantially brings back NEA. B-doped diamond film is expected to be used in electron multiplier, field emission cathode and particle/photon detector.