Compact silicon carbide photoconductive switch for high power applications: experiments and simulation

A novel SiC photoconductive switch designed and packaged for optimal performance under hostile operating conditions is presented. The use of semiinsulating SiC material with inherent defects (trap) sites and triggered by optical energy to be used as a high-power switch for compact pulsed power applications is discussed. The switching operations differs from previous attempts in that the optical source which is also used as the triggering mechanism has photon energy which is less than the band gap energy of SiC. Increase in performance is achieved by using stacked epi layers. Detailed design of the experimental test setup, including high frequency current and voltage measurement, pulse charge system, and optical energy distribution system is presented. The data for DC and pulsed charged switch is compared with the simulation results which include modeling of the recombination times of the defect states that are ionized as a result of carrier transition into the conduction band.