Prebreakdown Processes in a Metal Surface Microprotrusion Exposed to an RF Electromagnetic Field

A 2-D two-temperature model has been developed to simulate the heating of a microprotrusion on a metal surface exposed to a radio frequency (~10 GHz) electromagnetic field. The numerical simulation using this model includes a self-consistent calculation of the electric field at the microprotrusion surface and the field emission characteristics of the microprotrusion using the particle-in-cell method, a calculation of the current density distribution in the microprotrusion, and a calculation of the lattice and electron temperatures with the use of the heat equation taking into account the Joule and Nottingham effects, and also the finite rate of the heat exchange between the electrons and the lattice. The microprotrusion heating time has been calculated in relation to the electric field enhancement factor and to the electron-phonon interaction parameters.