Initiation of explosive electron emission in microwave fields

The microwave breakdown has been studied for the case in which it is caused by the heating and subsequent thermal destruction of the micropoints present on the cathode surface subjected to the action of a rapidly varying electric field. The heating of a micropoint by the emission current induced by a microwave field has been numerically simulated using the two-temperature model. The delay time to breakdown has been calculated as a function of the frequency of the electric field oscillation for different micropoint geometries.