Subnanosecond high-density current interruption in SOS diodes

An experimentally discovered phenomenon of the interruption of a high-density current in semiconductor opening switches (SOS diodes) within subnanosecond time range has been investigated. Used in the experiment was an all-solid-state SOS-based pulse generator that was operated as a charging power source for an auxiliary energy compression stage. This stage incorporated a capacitive energy store, a magnetic switch, an inductive energy store, and a test SOS diode with a load connected in parallel to the latter. The forward pumping time for the SOS diode was determined by the duration of the pulse produced by the charging generator and was between 25 and 40 ns, the duration of the reverse pumping was about 10 ns. Under these conditions, the time of current interruption in the test SOS diode was 0.5-0.7 ns for the current density being several kiloamps per square centimeter. The voltage pulse across a load of resistance several hundreds of Ohms had a peak voltage up to 150 kV, the FWHM 2-3 ns, and the rise/fall time about 1 ns. The fact that the generator incorporated no gas switch made it possible to raise the pulse repetition rate, that was limited only by the thermal loading on the circuit components, to 5 kHz.