| 摘要 |
<p>The electron impact surface (19) of an anode (13) is coated with a pyrocarbon coating (21) to reduce the production of secondary electrons and, concomitantly, to suppress the formation of neutral gases and plasma. First, a coating of a carbonizable resin is applied to the surface (19), followed by baking the anode (13) to at least 700 °C in a non-oxidizing atmosphere. The baking decomposes the resin, leaving a layer of porous carbon char on the surface (19). Next, the carbonized anode (13) is heated to at least 1000 °C while a low-pressure hydrocarbon gas, e.g., methane, is flowed over the char. The gas decomposes, depositing carbon on the char, which infiltrates the char and creates a non-porous, rigid layer (21) of pyrocarbon that is electrically conductive. The anode (13) is then heated in a vacuum oven to evaporate any residual water in the pyrocarbon coating (21).</p> |
