Abstract:
To investigate the charging characteristics of the dielectric-conductor alternately layered structure, various samples are designed and irradiated by the
90Sr β source to simulate the energetic-electron environment in space and the sample charging potentials are measured during the experiment. By using the 3-D simulation tool of deep dielectric charging, various structures are modeled and the charging potential and the electric field are calculated numerically. Experimental and simulation results show that the maximum dielectric surface potential and the built-in electric field of the structure are positively correlated with the width and the height (over the conductor surface) of the dielectric. The wider or higher the dielectric is, the greater the discharging risk will be. Especially when there is a narrow gap between the dielectric and the conductor, the electric field inside the dielectric will be enhanced dramatically and may result in an internal break-down. The electric field in the gap region might easily exceed the vacuum break-down threshold value. To mitigate the internal charging hazards of such structures in space engineering applications, the width and the height of the dielectric should be minimized as far as possible and the gap between the dielectric and the conductor must be avoided.