THE APPLICATION OF AN ENERGY-SELECTIVE IMAGING TECHNIQUE TO A STUDY OF FIELD-INDUCED HOT-ELECTRONS FROM BROAD-AREA HIGH-VOLTAGE ELECTRODES

A new instrumental technique has been developed for providing an energy-selective display of the field-induced hot-electron emission images obtained from localized "sites" on broad-area vacuum-insulated high-voltage electrodes. This technique has combined the field emission imaging and energy-tuning capabilities of a high-resolution electron spectrometer to produce a spatial display of energy-selected electrons emitted from a given site. The experimental findings have shown that there exist two types of emission process, characterized, respectively, by two types of emission image. A detailed consideration is given to the physical nature of the emission mechanisms which promote these two types of images.