An Analysis of Field-Induced Hot-Electron Emission from Metal-Insulator Microstructures on Broad-Area High-Voltage Electrodes

High-resolution electron energy distribution measurements of individual microscopic sites have been used to develop a detailed theoretical model of the field-induced hot-electron emission mechanism responsible for pre-breakdown currents at vacuum-gap fields of 10-30 MV m-1. The model, which is based on the formation of conducting channels in a metal-insulator-vacuum (m. i. v.) micro-emission régime, has provided experimentally verified quantitative relations for the current-voltage characteristic, spectral shape, and the field-dependence of the spectral full width at half maximum (f. w. h. m.) and shift.