Repetitive short pulse SOS-generators

The recently detected effect of the subnanosecond interruption of high-density currents in SOS-diodes opens up fresh opportunities in generation of powerful high-voltage short pulses. The study of the SOS-diodes showed that the current interruption time decreased to 500-600 ps when the reverse pumping time was reduced to 10-15 ns. A subnanosecond SOS-diode, which cuts off a 1-kA current in 600 ps, served as the basis for development of a pulse generator that produces pulses having the amplitude of 150-250 kV, the half-height duration of 3 to 4 ns, and the repetition frequency up to 5 kHz in a 30-second burst. A more powerful generator produces pulses having the duration of 5 to 6 ns, the power of 400 to 500 MW, the voltage of up to 400 kV, and the repetition frequency up to 2 kHz in the burst mode. These generators do not contain gas-discharge switches. As a result, they combine a high repetition frequency and stability of pulses, boast of virtually unlimited (solid-state) service life, and offer a high specific average power. These properties are especially important for high-power short-pulse generators intended for commercial applications. Physical processes that take place in the semiconductor structure of the SOS-diodes operating for subnanosecond interruption of currents are discussed. The circuitry and design of the short-pulse generators are described. Results of the tests performed on the said generators are reported.