Characterization of Electron Emission from Broad Area Composite Emitter

This work studies the emission of electrons from Copper Broad Area Emitter (CBAE) in addition to Copper Broad Area Composite Emitter (CBACE) and provides an explanation of the switch-on phenomenon based on the formation of conductive channels and traps. The samples were examined using field electron microscopy (FEM) at high vacuum conditions (10
⁻⁶
mbar) and a voltage of 15 kV, with the emitter placed 5 mm away from the anode. Scanning electron microscopy (SEM) was used to characterise the epoxy layer after voltage application. The results based on current and voltage characteristics showed that a breakdown of the epoxy layer occurred due to the emission of current at 13 kV.