Electron field emission from a cesiated NEA diamond(100) surface: An activation concept

Electron field emission (FE) was measured from a natural doped diamond (100) surface prepared to show a negative electron affinity (NEA). While the bare surface showed no FE, emission was observed from the cesiated surface after an activation phase. A model for FE from a cesiated surface is presented. The assumption of activation also proved to be a valuable concept when looking at FE from CVD films. The nature of this activation may consist of an increase in the emitting surface area, which would account for the higher FE current by a breakdown between anode and cathode. At the same time morphological changes were observed by AFM, perhaps showing amorphization.