High current photoconductive semiconductor switches

摘要

It is shown that Si photoconductive semiconductor switches (PCSSs)can be used to switch high voltages (up to 123 kV), high fields (up to82 kV/cm) and high currents (2.8 kA). The ability of the samples towithstand this type of high-voltage, high-current switching depends onthe way in which the current penetrates the semiconductor. Theappropriate use of water or contacts greatly improves the switchingcapability. It is also shown that the wafers can support large currents(4.0 kA for GaAs and 2.8 kA for Si) and large linear current densities(3.2 kA/cm for GaAs and 1.4 kA/cm for Si). For GaAs, this linear currentdensity corresponds to about 1 MA/cm², given a penetrationdepth of about 10^-3 cm. It is determined that the lock-onphenomenon can be triggered with light of varying photon energy to reacha lock-on field that is both impurity-concentration andsample-temperature dependent