M-Type Cathode Characterization Using a Kelvin Probe System in Vacuum Chamber

High-performing dispenser cathodes are an essential component of modern vacuum electron devices (VEDs). Therefore, it is important to quantify their emission performance. In order to assess how well a cathode emits electrons, it is useful to measure the emitting surface's work function, or the energy input required to liberate an electron from the material. A lower work function is desirable because it should facilitate higher emitted current densities and longer service lifetimes. This work presents both emission data and work function measurements collected using a customized Kelvin Probe System (KPS) and one of the most common types of cathodes, the M-type cathode.