Initiation mechanism of pulsed surface flashover along silicon in vacuum by pre-breakdown conduction and photon emission

Abstract

Pre-breakdown (leakage) and breakdown currents and photon-emission associated with the currents, under impulse (0.36/10 /spl mu/s) voltage stress, along high purity (p>30 K/spl Omega/cm) silicon, with and without gold end contacts in vacuum (/spl tilde/10/sup -6/ Torr), are discussed. Three distinct phases leading to the breakdown condition are observed. These are one-carrier (hole) leakage current, two-carrier (electrons and holes) current, and complete surface flashover processes. The onset of photon-emission coincides with the onset of two-carrier current. The temporally resolved one-carrier leakage current (ohmic or charge injection dominated) and photon-emission data show that there is a certain threshold leakage current which initiates the rest of the processes.