Thermally stimulated exoelectron emission of BeO: Excitation by low energy electron impact

The thermally stimulated exoelectron emission (TSEE) of oxide films on polycristalline Be substrates can be excited by extremely low energy electron bombardment (primary energies below 5 eV). The emission intensity as a function of primary energy is different for the two groups of high and low temperature glow peaks. A threshold of excitation for the glow maxima below 400°C cannot be measured down to excitation energies of 1 eV, whereas a resonance in the excitation function is found around 3.5 eV for the peaks above that temperature. These excitation functions are discussed in connection with the present emission concepts of BeO.