Diamond bonding and metallization for electron transmission cathodes

Abstract

We report progress in mounting small thin diamond sheets over holes in larger substrates in a manner that allows electron beam amplification. In addition to a physical mount, our bonding method must be compatible with the creation and maintenance of the negative electron affinity surface and operation at elevated temperatures. We use a transient liquid phase bonding method wherein the constituent metals react to increase their melting point and also reduce their vapor pressure.