High-Power Ultrafast Current Switching by a Silicon Sharpener Operating at an Electric Field Close to the Threshold of the Zener Breakdown

A new principle of high-power ultrafast current switching by Si sharpener based on a successive breakdown of the series-connected structures has been experimentally implemented and theoretically studied. A voltage pulse with an amplitude of 180 kV and a rise time of 400 ps was applied to a semiconductor device containing 44 series-connected diode structures located in a 50- transmission line. Due to a sharp nonuniformity of the applied voltage distribution across the length of the device, the structures operate in the successive breakdown mode. Each successive structure breaks down with a shorter time interval as the electromagnetic shockwave builds. In the experiments in a 50- transmission line, we have obtained 150-kV output pulses having a 100-ps rise time. The maximum current and voltage rise rates amount to 30 kA/ns and 1.5 MV/ns, respectively. In the numerical simulations, the ionization rate of the process-induced deep-level centers, as well as the band-to-band tunneling, is taken into account. The calculations show that, at a reverse voltage rise rate across the structure of over 10^13  V/s, the electric fields that are close to the threshold of the Zener breakdown can be achieved even if the structure contains deep-level centers with a concentration of 10¹¹ to 10¹² cm^-3.