Peculiarities of constructing planar microminiature current sources based on secondary emission cathode excited by an edge FEA

The current characteristics of a microminiature current source are theoretically studied. It is based on a secondary emission cathode excited by the current from a field emission array (FEA). This principle of constructing current sources allows the current from the FEA to be amplified by 10 times or more by using film materials which show high secondary emission coefficient, for example, MgO, Al2O3, and BeO. These features yield an opportunity for a substantially longer durability for a film FEA and the source as a whole.