Insulation Design of Printed Circuit Boards Under Electron Irradiation

Abstract

This paper deals with the surface flashover characteristics of dielectric material during electron irradiation in vacuum in order to design the conductive patterns on printed circuit boards used inside spacecraft adequately. The dielectric material and the electrodes printed on it were irradiated with the electrons of the energy lower than 10keV. DC voltage was applied between the two electrodes during electron irradiation. The voltage was increased step-wisely until the surface flashover occurred on the dielectric. We obtained the result that the surface flashover voltage increased with the insulation distance between the electrodes. However, the flashover voltage in the case with electron irradiation was lower than that without electron irradiation. The flashover voltage characteristics were obtained as parameters of the insulation distance and the electron energy. The characteristics were explained by the currents flowing between the electrodes under electron irradiation.