| 摘要 |
<p>PURPOSE:To provide a low-temperature-operation impregnated cathode which is coated with a mixed thin film formed of W and oxide containing W, Sc, O to reduce nonuniform distribution of work function on the surface of the cathode, or to reduce batch field effect. CONSTITUTION:A porous base 1 for a substrate-impregnated cathode pellet 3 is manufactured by heat resistant metal sintered material sized 1-5mum, smaller than that for conventional cathodes. The cavity percentage of the porous base 1 is within 25-32%, to provide a low work function (Ba, Sc, O) composite layer 8 uniformly on the surface of the cathode during operation.</p> |
