Temporal behavior of surface charge accumulation in bridged vacuum gaps

Temporal change in electric field strength at the insulator-cathode-vacuum interface accompanied by charging of the insulator have been studied by using a two-dimensional Monte Carlo simulation. The study employed cylindrical and conical insulators. Each of the insulators was made of PMMA, polyimide or Al/sub 2/O/sub 3/. The field strength with cylindrical insulators shows an abrupt increase, and with conical insulators a rapid reduction. Dependencies of the field change on the applied voltage height and material are demonstrated. Flashovers occur after the simulated field change.<
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