Improvement of the E-field triggered surface breakdown of dielectric anodes in vacuum ion diodes

Summary form only given. To improve the dielectric flashover of adsorbates at the surface of the hydrocarbon inserts of vacuum diode anodes, start-electrons are implemented by several means. The first method is to trap a layer of electrons at the structured surface (grooves) by means of auxiliary electrodes. This improves the microscopic and macroscopic homogeneity of the ion beam. A second method uses the idea that an electrically weak conducting surface layer donates electrons into the adsorbates, if the electric field parallel to the surface exceeds 10 kV/mm. Experiments with a pinch reflex diode at the 1.2-TW pulse generator Kalif´ have been conducted. Glass-fiber-woven anode inserts have been tested. The weak conductivity of glass and the ability to trap a desired amount of adsorbates (H₂, He, and N ₂, for example) make it possible to form proper plasmas and to do it without hydrocarbon. It was shown that the microinhomogeneity of the ion beam could be reduced drastically