Suppression of prebreakdown current by a cathode coating of silicon

摘要

Reduction of prebreakdown current by three orders of magnitude is reported for Si coatings up to 1.1 μm thick on stainless steel in the range of electric field from 0.25 to 1.0 MV/cm, in vacuum gaps of ∼300 μm. These results, as well as earlier results with CaF2 coatings reported by the author, are adequately described by a simple double‐barrier high‐field tunneling model which then suggests electronic criteria for coatings to be most effective in suppressing prebreakdown current in HV vacuum applications.